A Kernel Embedding-Based Approach for Nonstationary Causal Model Inference.

PubMed

Hu, Shoubo; Chen, Zhitang; Chan, Laiwan

2018-05-01

Although nonstationary data are more common in the real world, most existing causal discovery methods do not take nonstationarity into consideration. In this letter, we propose a kernel embedding-based approach, ENCI, for nonstationary causal model inference where data are collected from multiple domains with varying distributions. In ENCI, we transform the complicated relation of a cause-effect pair into a linear model of variables of which observations correspond to the kernel embeddings of the cause-and-effect distributions in different domains. In this way, we are able to estimate the causal direction by exploiting the causal asymmetry of the transformed linear model. Furthermore, we extend ENCI to causal graph discovery for multiple variables by transforming the relations among them into a linear nongaussian acyclic model. We show that by exploiting the nonstationarity of distributions, both cause-effect pairs and two kinds of causal graphs are identifiable under mild conditions. Experiments on synthetic and real-world data are conducted to justify the efficacy of ENCI over major existing methods.

Smear correction of highly variable, frame-transfer CCD images with application to polarimetry.

PubMed

Iglesias, Francisco A; Feller, Alex; Nagaraju, Krishnappa

2015-07-01

Image smear, produced by the shutterless operation of frame-transfer CCD detectors, can be detrimental for many imaging applications. Existing algorithms used to numerically remove smear do not contemplate cases where intensity levels change considerably between consecutive frame exposures. In this report, we reformulate the smearing model to include specific variations of the sensor illumination. The corresponding desmearing expression and its noise properties are also presented and demonstrated in the context of fast imaging polarimetry.

Note: An inexpensive square waveform ion funnel driver

NASA Astrophysics Data System (ADS)

Hoffman, Nathan M.; Opačić, Bojana; Reilly, Peter T. A.

2017-01-01

An inexpensive frequency variable square waveform generator (WFG) was developed to use with existing sinusoidal waveform driven ion funnels. The developed WFG was constructed using readily available low voltage DC power supplies and discrete components placed in printed circuit boards. As applied to ion funnels, this WFG represents considerable cost savings over commercially available products without sacrificing performance. Operation of the constructed pulse generator has been demonstrated for a 1 nF ion funnel at an operating frequency of 1 MHz while switching 48 Vp-p.

Note: An inexpensive square waveform ion funnel driver.

PubMed

Hoffman, Nathan M; Opačić, Bojana; Reilly, Peter T A

2017-01-01

An inexpensive frequency variable square waveform generator (WFG) was developed to use with existing sinusoidal waveform driven ion funnels. The developed WFG was constructed using readily available low voltage DC power supplies and discrete components placed in printed circuit boards. As applied to ion funnels, this WFG represents considerable cost savings over commercially available products without sacrificing performance. Operation of the constructed pulse generator has been demonstrated for a 1 nF ion funnel at an operating frequency of 1 MHz while switching 48 V p-p .

Cultural and cognitive considerations in the prevention of American Indian adolescent suicide.

PubMed

LaFromboise, T D; Bigfoot, D S

1988-06-01

A description of cultural considerations associated with American Indian adolescent coping is presented within a transactional, cognitive-phenomenological framework. Select cultural values and cultural beliefs of American Indians associated with death are discussed in terms of person variables and situational demand characteristics that interplay in the transactional coping process. Three situational demand characteristics (ambiguity of identity, frequency of loss, and pervasiveness of hardships) are then presented to illustrate the reciprocal relationship between environmental contingencies and American Indian individual and community efforts at coping. The dynamic interdependence between person and environmental variables is emphasized and considered essential for inclusion in the design of interventions to prevent suicide. Existing intervention efforts with American Indian adolescent suicide attempters are reviewed and a school-wide cognitive behavioural approach based on the transactional model of coping with suicide is described. It is suggested that on-going cognitive restructuring, social skills training, and peer counselling training activities be culturally adapted and integrated into relevant areas of the school curricula in order that coping be enhanced and suicide ameliorated.

Developing a historical climatology of Wales from Welsh and English language sources

NASA Astrophysics Data System (ADS)

MacDonald, N.; Davies, S. J.; Jones, C. A.; Charnell-White, C.

2009-04-01

Historical documentary records are recognised as valuable in understanding long term climate variability. In the UK, the Central England Temperature Series (1772- ) and the Lamb weather catalogue (1861- ) provide a detailed climate record for England, but the value of these archives in Wales and Scotland is more limited, though some long term instrumental series exist, particularly for cities such as Cardiff. The spatial distance from the central England area and a lower density of instrumental stations in Wales has limited understanding of climate variability during the instrumental period (~1750- ). This paper illustrates that historical documentary records represent a considerable resource, that to date have been underutilised in developing a more complete understanding of past weather and climate within many parts of Western Europe.

The magnetospheric disturbance ring current as a source for probing the deep earth electrical conductivity

USGS Publications Warehouse

Campbell, W.H.

1990-01-01

Two current rings have been observed in the equatorial plane of the earth at times of high geomagnetic activity. An eastward current exists between about 2 and 3.5 earth radii (Re) distant, and a larger, more variable companion current exists between about 4 and 9 Re. These current regions are loaded during geomagnetic substorms. They decay, almost exponentially, after the cessation of the particle influx that attends the solar wind disturbance. This review focuses upon characteristics needed for intelligent use of the ring current as a source for induction probing of the earth's mantle. Considerable difficulties are found with the assumption that Dst is a ring-current index. ?? 1990 Birkha??user Verlag.

Exposure Estimation and Interpretation of Occupational Risk: Enhanced Information for the Occupational Risk Manager

PubMed Central

Waters, Martha; McKernan, Lauralynn; Maier, Andrew; Jayjock, Michael; Schaeffer, Val; Brosseau, Lisa

2015-01-01

The fundamental goal of this article is to describe, define, and analyze the components of the risk characterization process for occupational exposures. Current methods are described for the probabilistic characterization of exposure, including newer techniques that have increasing applications for assessing data from occupational exposure scenarios. In addition, since the probability of health effects reflects variability in the exposure estimate as well as the dose-response curve—the integrated considerations of variability surrounding both components of the risk characterization provide greater information to the occupational hygienist. Probabilistic tools provide a more informed view of exposure as compared to use of discrete point estimates for these inputs to the risk characterization process. Active use of such tools for exposure and risk assessment will lead to a scientifically supported worker health protection program. Understanding the bases for an occupational risk assessment, focusing on important sources of variability and uncertainty enables characterizing occupational risk in terms of a probability, rather than a binary decision of acceptable risk or unacceptable risk. A critical review of existing methods highlights several conclusions: (1) exposure estimates and the dose-response are impacted by both variability and uncertainty and a well-developed risk characterization reflects and communicates this consideration; (2) occupational risk is probabilistic in nature and most accurately considered as a distribution, not a point estimate; and (3) occupational hygienists have a variety of tools available to incorporate concepts of risk characterization into occupational health and practice. PMID:26302336

Two centuries of observed atmospheric variability and change over the North Sea region

NASA Astrophysics Data System (ADS)

Stendel, Martin; van den Besselaar, Else; Hannachi, Abdel; Kent, Elizabeth; Lefebvre, Christiana; van Oldenborgh, Geert Jan; Rosenhagen, Gudrun; Schenk, Frederik; van der Schrier, Gerard

2015-04-01

Situated in northwestern Europe, the North Sea region is under influence of air masses from subtropical to arctic origin, and thus exhibits significant natural climate variability. As the land areas surrounding the North Sea are densely populated, climate change is an important issue in terms of e.g. coastal protection, fishery and trade. This study is part of the NOSCCA initiative (North Sea Region Climate Change Assessment) and presents observed variability and changes in atmospheric parameters during the last roughly 200 years. Circulation patterns show considerable decadal variability. In recent decades, a northward shift of storm tracks and increased cyclonic activity has been observed. There is also an indication of increased persistence of weather types. The wind climate is dominated by large multidecadal variability, and no robust long-term trends can be identified in the available datasets. There is a clear positive trend in near-surface temperatures, in particular during spring and winter. Over the region as a whole, no clear long-term precipitation trends are visible, although regional indications exist for an increased risk of extreme precipitation events.

Rural hospital wages

PubMed Central

Hendricks, Ann M.

1989-01-01

Average fiscal year 1982 wages from 2,302 rural American hospitals were used to test for a gradient descending from hospitals in counties adjacent to metropolitan areas to those not adjacent. Considerable variation in the ratios of adjacent to nonadjacent averages existed. No statistically significant difference was found, however. Of greater importance in explaining relative wages within States were occupational mix, mix of part-time and full-time workers, case mix, presence of medical residencies, and location in a high-rent county within the State. Medicare already adjusts payments for only two of these variables. PMID:10313454

Pharmacotherapy for alcohol dependence: perceived treatment barriers and action strategies among Veterans Health Administration service providers.

PubMed

Harris, Alex H S; Ellerbe, Laura; Reeder, Rachelle N; Bowe, Thomas; Gordon, Adam J; Hagedorn, Hildi; Oliva, Elizabeth; Lembke, Anna; Kivlahan, Daniel; Trafton, Jodie A

2013-11-01

Although access to and consideration of pharmacological treatments for alcohol dependence are consensus standards of care, receipt of these medications by patients is generally rare and highly variable across treatment settings. The goal of the present project was to survey and interview the clinicians, managers, and pharmacists affiliated with addiction treatment programs within Veterans Health Administration (VHA) facilities to learn about their perceptions of barriers and facilitators regarding greater and more reliable consideration of pharmacological treatments for alcohol dependence. Fifty-nine participants from 19 high-adopting and 11 low-adopting facilities completed the survey (facility-level response rate = 50%) and 23 participated in a structured interview. The top 4 barriers to increased consideration and use of pharmacotherapy for alcohol dependence were consistent across high- and low-adopting facilities and included perceived low patient demand, pharmacy procedures or formulary restrictions, lack of provider skills or knowledge regarding pharmacotherapy for alcohol dependence, and lack of confidence in treatment effectiveness. Low patient demand was rated as the most important barrier for oral naltrexone and disulfiram, whereas pharmacy or formulary restrictions were rated as the most important barrier for acamprosate and extended-release naltrexone. The 4 strategies rated across low- and high-adopting facilities as most likely to facilitate consideration and use of pharmacotherapy for alcohol dependence were more education to patients about existing medications, more education to health care providers about medications, increased involvement of physicians in treatment for alcohol dependence, and more compelling research on existing medications. This knowledge provides a foundation for designing, deploying, and evaluating targeted implementation efforts.

General properties of solutions to inhomogeneous Black-Scholes equations with discontinuous maturity payoffs

NASA Astrophysics Data System (ADS)

O, Hyong-Chol; Jo, Jong-Jun; Kim, Ji-Sok

2016-02-01

We provide representations of solutions to terminal value problems of inhomogeneous Black-Scholes equations and study such general properties as min-max estimates, gradient estimates, monotonicity and convexity of the solutions with respect to the stock price variable, which are important for financial security pricing. In particular, we focus on finding representation of the gradient (with respect to the stock price variable) of solutions to the terminal value problems with discontinuous terminal payoffs or inhomogeneous terms. Such terminal value problems are often encountered in pricing problems of compound-like options such as Bermudan options or defaultable bonds with discrete default barrier, default intensity and endogenous default recovery. Our results can be used in pricing real defaultable bonds under consideration of existence of discrete coupons or taxes on coupons.

Atmospheric Teleconnection and Climate Variability: Affecting Rice Productivity of Bihar, India

NASA Astrophysics Data System (ADS)

Saini, A.

2017-12-01

Climate variability brought various negative results to the environment around us and area under rice crop in Bihar has also faced a lot of negative impacts due to variability in temperature and rainfall. Location of Bihar in Northern Plain of India automatically makes it prime location for agriculture and therefore variability in climatic variables brings highly sensitive results to the agricultural production (especially rice). In this study, rainfall and temperature variables are taken into consideration to investigate the impact on rice cultivated area. Change in climate variable with the passage of time is prevailing since the start of geological time scale, how the variability in climate variables has affected the major crops. Climate index of Pacific Ocean and Indian Ocean influences the seasonal weather in Bihar and therefore role of ENSO and IOD is an interesting point of inquiry. Does there exists direct relation between climate variability and area under agricultural crops? How many important variables directly signals towards the change in area under agriculture production? These entire questions are answered with respect to change in area under rice cultivation of Bihar State of India. Temperature, rainfall and ENSO are a good indicator with respect to rice cultivation in Indian subcontinent. Impact on the area under rice has been signaled through ONI, Niño3 and DMI. Increasing range of temperature in the rice productivity declining years is observed since 1990.

Optimizing the Benefits of Exercise on Physical Function in Older Adults

PubMed Central

Buford, Thomas W.; Anton, Stephen D.; Clark, David J.; Higgins, Torrance J.; Cooke, Matthew B.

2014-01-01

As the number of older adults continues to rise worldwide, the prevention of physical disability among seniors is an increasingly important public health priority. Physical exercise is among the best known methods of preventing disability, but accumulating evidence indicates that considerable variability exists in the responsiveness of older adults to standard training regimens. Accordingly, a need exists to develop tailored interventions to optimize the beneficial effects of exercise on the physical function of older adults at risk for becoming disabled. The present review summarizes the available literature related to the use of adjuvant or alternative strategies intended to enhance the efficacy of exercise in improving the physical function of older adults. Within this work, we also discuss potential future research directions in this area. PMID:24361365

Hydro power flexibility for power systems with variable renewable energy sources: an IEA Task 25 collaboration: Hydro power flexibility for power systems

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

Huertas-Hernando, Daniel; Farahmand, Hossein; Holttinen, Hannele

2016-06-20

Hydro power is one of the most flexible sources of electricity production. Power systems with considerable amounts of flexible hydro power potentially offer easier integration of variable generation, e.g., wind and solar. However, there exist operational constraints to ensure mid-/long-term security of supply while keeping river flows and reservoirs levels within permitted limits. In order to properly assess the effective available hydro power flexibility and its value for storage, a detailed assessment of hydro power is essential. Due to the inherent uncertainty of the weather-dependent hydrological cycle, regulation constraints on the hydro system, and uncertainty of internal load as wellmore » as variable generation (wind and solar), this assessment is complex. Hence, it requires proper modeling of all the underlying interactions between hydro power and the power system, with a large share of other variable renewables. A summary of existing experience of wind integration in hydro-dominated power systems clearly points to strict simulation methodologies. Recommendations include requirements for techno-economic models to correctly assess strategies for hydro power and pumped storage dispatch. These models are based not only on seasonal water inflow variations but also on variable generation, and all these are in time horizons from very short term up to multiple years, depending on the studied system. Another important recommendation is to include a geographically detailed description of hydro power systems, rivers' flows, and reservoirs as well as grid topology and congestion.« less

Mathematics and Science Learning Opportunities in Preschool Classrooms

PubMed Central

Piasta, Shayne B.; Pelatti, Christina Yeager; Miller, Heather Lynnine

2014-01-01

Research findings The present study observed and coded instruction in 65 preschool classrooms to examine (a) overall amounts and (b) types of mathematics and science learning opportunities experienced by preschool children as well as (c) the extent to which these opportunities were associated with classroom and program characteristics. Results indicated that children were afforded an average of 24 and 26 minutes of mathematics and science learning opportunities, respectively, corresponding to spending approximately 25% of total instructional time in each domain. Considerable variability existed, however, in the amounts and types of mathematics and science opportunities provided to children in their classrooms; to some extent, this variability was associated with teachers’ years of experience, teachers’ levels of education, and the socioeconomic status of children served in the program. Practice/policy Although results suggest greater integration of mathematics and science in preschool classrooms than previously established, there was considerable diversity in the amounts and types of learning opportunities provided in preschool classrooms. Affording mathematics and science experiences to all preschool children, as outlined in professional and state standards, may require additional professional development aimed at increasing preschool teachers’ understanding and implementation of learning opportunities in these two domains in their classrooms. PMID:25489205

Engine design considerations for 2nd generation supersonic transports

NASA Technical Reports Server (NTRS)

Howlett, R. A.

1975-01-01

The environmental and economic goals projected for advanced supersonic transports will require revolutionary improvements in propulsion systems. Variable cycle engine concepts that incorporate unique components and advanced technologies show promise in meeting these goals. Pratt & Whitney Aircraft is conducting conceptual design studies of variable cycle engine concepts under NASA sponsorship. This paper reviews some of the design considerations for these engine concepts. Emphasis is placed on jet noise abatement, reduction of emissions, performance improvements, installation considerations, hot-section characteristics and control system requirements. Two representative variable cycle engine concepts that incorporate these basic design considerations are described.

Single stage queueing/manufacturing system model that involves emission variable

NASA Astrophysics Data System (ADS)

Murdapa, P. S.; Pujawan, I. N.; Karningsih, P. D.; Nasution, A. H.

2018-04-01

Queueing is commonly occured at every industry. The basic model of queueing theory gives a foundation for modeling a manufacturing system. Nowadays, carbon emission is an important and inevitable issue due to its huge impact to our environment. However, existing model of queuing applied for analysis of single stage manufacturing system has not taken Carbon emissions into consideration. If it is applied to manufacturing context, it may lead to improper decisisions. By taking into account of emission variables into queuing models, not only the model become more comprehensive but also it creates awareness on the issue to many parties that involves in the system. This paper discusses the single stage M/M/1 queueing model that involves emission variable. Hopefully it could be a starting point for the next more complex models. It has a main objective for determining how carbon emissions could fit into the basic queueing theory. It turned out that the involvement of emission variables into the model has modified the traditional model of a single stage queue to a calculation model of production lot quantity allowed per period.

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

Balser, S.; Sankar, S.; Miller, R.

In order to more fully integrate renewable resources, such as wind and solar, into the transmission system, additional capacity must be realized in the short term using the installed transmission capacity that exists today. The U.S. Department of Energy (DOE) and the National Renewable Energy Laboratory Transmission and Grid Integration Group supported this study to assemble the history of regulations and status of transmission technology to expand existing grid capacity. This report compiles data on various transmission technology methods and upgrades for increased capacity utilization of the existing transmission system and transmission corridors. The report discusses the technical merit ofmore » each method and explains how the method could be applied within the current regulatory structure to increase existing transmission conductor and/or corridor capacity. The history and current state of alternatives to new construction is presented for regulators, legislators, and other policy makers wrestling with issues surrounding integration of variable generation. Current regulations are assessed for opportunities to change them to promote grid expansion. To support consideration of these alternatives for expanding grid capacity, the report lists relevant rules, standards, and policy changes.« less

Mapping the structure of perceptual and visual-motor abilities in healthy young adults.

PubMed

Wang, Lingling; Krasich, Kristina; Bel-Bahar, Tarik; Hughes, Lauren; Mitroff, Stephen R; Appelbaum, L Gregory

2015-05-01

The ability to quickly detect and respond to visual stimuli in the environment is critical to many human activities. While such perceptual and visual-motor skills are important in a myriad of contexts, considerable variability exists between individuals in these abilities. To better understand the sources of this variability, we assessed perceptual and visual-motor skills in a large sample of 230 healthy individuals via the Nike SPARQ Sensory Station, and compared variability in their behavioral performance to demographic, state, sleep and consumption characteristics. Dimension reduction and regression analyses indicated three underlying factors: Visual-Motor Control, Visual Sensitivity, and Eye Quickness, which accounted for roughly half of the overall population variance in performance on this battery. Inter-individual variability in Visual-Motor Control was correlated with gender and circadian patters such that performance on this factor was better for males and for those who had been awake for a longer period of time before assessment. The current findings indicate that abilities involving coordinated hand movements in response to stimuli are subject to greater individual variability, while visual sensitivity and occulomotor control are largely stable across individuals. Copyright © 2015 Elsevier B.V. All rights reserved.

The limits of life on Earth and searching for life on Mars

NASA Technical Reports Server (NTRS)

Nealson, K. H.

1997-01-01

Considerations of basic properties of bacteria such as size, structure, and metabolic versatility allow one to understand how these remarkable life-forms are so adaptable to environments previously thought to be uninhabitable. It is now appreciated that bacteria on Earth can utilize almost any redox couple that yields energy, taking advantage of this energy, while transforming the elements during metabolism. The ability to grow at the expense of inorganic redox couples allows the microbes to occupy niches not available to the more metabolically constrained eukaryotes. Furthermore, the simplicity of the bacterial structure allows them considerably more resistance to environmental variables (pH, salinity, temperature) that are toxic or lethal to more complex organisms. This information can be used to explain the predominance of prokaryotes in extreme environments on Earth, and to speculate as to simple types of metabolism and biogeochemical cycles that may exist on this planet, Mars, and perhaps other non-Earth environments.

The limits of life on Earth and searching for life on Mars.

PubMed

Nealson, K H

1997-10-25

Considerations of basic properties of bacteria such as size, structure, and metabolic versatility allow one to understand how these remarkable life-forms are so adaptable to environments previously thought to be uninhabitable. It is now appreciated that bacteria on Earth can utilize almost any redox couple that yields energy, taking advantage of this energy, while transforming the elements during metabolism. The ability to grow at the expense of inorganic redox couples allows the microbes to occupy niches not available to the more metabolically constrained eukaryotes. Furthermore, the simplicity of the bacterial structure allows them considerably more resistance to environmental variables (pH, salinity, temperature) that are toxic or lethal to more complex organisms. This information can be used to explain the predominance of prokaryotes in extreme environments on Earth, and to speculate as to simple types of metabolism and biogeochemical cycles that may exist on this planet, Mars, and perhaps other non-Earth environments.

Study report on combining diagnostic and therapeutic considerations with subsystem and whole-body simulation

NASA Technical Reports Server (NTRS)

Furukawa, S.

1975-01-01

Current applications of simulation models for clinical research described included tilt model simulation of orthostatic intolerance with hemorrhage, and modeling long term circulatory circulation. Current capabilities include: (1) simulation of analogous pathological states and effects of abnormal environmental stressors by the manipulation of system variables and changing inputs in various sequences; (2) simulation of time courses of responses of controlled variables by the altered inputs and their relationships; (3) simulation of physiological responses of treatment such as isotonic saline transfusion; (4) simulation of the effectiveness of a treatment as well as the effects of complication superimposed on an existing pathological state; and (5) comparison of the effectiveness of various treatments/countermeasures for a given pathological state. The feasibility of applying simulation models to diagnostic and therapeutic research problems is assessed.

Sex Bias Exists in Human Surgical Clinical Research

PubMed Central

Mansukhani, Neel A.; Yoon, Dustin Y.; Teter, Katherine A.; Stubbs, Vanessa C.; Helenowski, Irene B.; Woodruff, Teresa K.; Kibbe, Melina R.

2016-01-01

Importance Sex is a variable that is poorly controlled for in clinical research. Objective Determine if sex bias exists in human surgical clinical research, determine if data are reported and analyzed using sex as an independent variable, and identify specialties where the greatest and least sex biases exist. Design Review and data abstraction from published peer-reviewed manuscripts. Setting All original peer-reviewed manuscripts published in 2011 and 2012 in Annals of Surgery, American Journal of Surgery, JAMA Surgery, Journal of Surgical Research, and Surgery. Main Outcome Measures Study type, location, number and sex of subjects, sex matching, and inclusion of sex-based reporting, statistical analysis, and discussion of data. Results Of 2,347 articles reviewed, 1,668 included human subjects. After excluding 365 articles, 1,303 manuscripts remained: 17 (1%) included only males, 41 (3%) included only females, 1,020 (78%) included males and females, and 225 (17%) did not document the sex of the subjects. While females represent over 50% of the total number of subjects included, considerable variability existed with the number of male, female, and unspecified subjects included among the journals, between US domestic and international studies, and between single versus multi-center studies. For manuscripts included in the study, only 38% reported these data by sex, 33% analyzed these data by sex, and 23% included a discussion of sex-based results. Sex matching of the subjects included in the research was poor, with only 18% of the studies matching the inclusion of both sexes by 80%. Upon analysis of the different surgical specialties, a wide variation in sex-based inclusion, matching, and data reporting existed, with colorectal surgery having the best matching of males and females and cardiac surgery having the worst. Conclusion Our data show that sex bias exists in human surgical clinical research. Few studies included men and women equally, less than one-third performed data analysis by sex, and there was wide variation in inclusion and matching of the sexes among the specialties and the journals reviewed. Because clinical research serves as the foundation for evidence-based medicine, it is imperative that this disparity be addressed so that therapies benefit both sexes. PMID:27551816

Judging the Neonatal Abstinence Syndrome Assessment Tools to Guide Future Tool Development: The use of Clinimetrics as Opposed to Psychometrics.

PubMed

Westgate, Philip M; Gomez-Pomar, Enrique

2017-01-01

In the face of the current Neonatal Abstinence Syndrome (NAS) epidemic, there is considerable variability in the assessment and management of infants with NAS. In this manuscript, we particularly focus on NAS assessment, with special attention given to the popular Finnegan Neonatal Abstinence Score (FNAS). A major instigator of the problem of variable practices is that multiple modified versions of the FNAS exist and continue to be proposed, including shortened versions. Furthermore, the validity of such assessment tools has been questioned, and as a result, the need for better tools has been suggested. The ultimate purpose of this manuscript, therefore, is to increase researchers' and clinicians' understanding on how to judge the usefulness of NAS assessment tools in order to guide future tool development and to reduce variable practices. In short, we suggest that judgment of NAS assessment tools should be made on a clinimetrics viewpoint as opposed to psychometrically. We provide examples, address multiple issues that must be considered, and discuss future tool development. Furthermore, we urge researchers and clinicians to come together, utilizing their knowledge and experience, to assess the utility and practicality of existing assessment tools and to determine if one or more new or modified tools are needed with the goal of increased agreement on the assessment of NAS in practice.

Cryomagmatism in the outer solar system

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

Kargel, J.S.

1990-01-01

Assemblages of cryovolcanic, tectonic, and impact structures form varied landscapes quite alien in their collective expression. Many variables can affect the cryovolcanic style of a satellite but none more so than cryolava composition. The compositional variable is examined in considerable detail. Existing knowledge of phase equilibria and physical properties of cosmochemically relevant unary, binary, and multi-component chemical systems are summarized. Where published knowledge was found lacking, measurements of the physical chemistry of volatile mixtures are presented. Cryovolcanic landscapes are briefly toured, and knowledge of the physical chemistry of volatile mixtures is applied to problems of cryovolcanological interest. Aqueous cryolavas maymore » range in composition from salt-water brines to cryogenic ammonia-water-rich multi-components solutions possibly involving methanol, ammonium sulfide, alkali chlorides, and many other potential components. Cryomagmatic distillation can greatly accentuate the importance of trace and minor constituents of icy satellites. The viscosities, densities, and other physical properties of these liquids vary considerably and depend sensitively on their exact compositions. These properties affect everything from cryovolcanic eruptive styles and landforms, to the way cryovolcanic crusts respond to tectonic stress. It is believed that the compositional variable is directly or indirectly implicated in a wide varity of geomorphic aspects of contrast among the icy satellites. Thus, even though as yet any specific morphology can be attributed to a specific composition, there appears to be a powerful link between composition of the ices originally accreted by a satellite and its subsequent interior evolution and exterior geomorphic appearance.« less

Imperfect physician assistant and physical therapist admissions processes in the United States

PubMed Central

2014-01-01

We compared and contrasted physician assistant and physical therapy profession admissions processes based on the similar number of accredited programs in the United States and the co-existence of many programs in the same school of health professions, because both professions conduct similar centralized application procedures administered by the same organization. Many studies are critical of the fallibility and inadequate scientific rigor of the high-stakes nature of health professions admissions decisions, yet typical admission processes remain very similar. Cognitive variables, most notably undergraduate grade point averages, have been shown to be the best predictors of academic achievement in the health professions. The variability of non-cognitive attributes assessed and the methods used to measure them have come under increasing scrutiny in the literature. The variance in health professions students’ performance in the classroom and on certifying examinations remains unexplained, and cognitive considerations vary considerably between and among programs that describe them. One uncertainty resulting from this review is whether or not desired candidate attributes highly sought after by individual programs are more student-centered or graduate-centered. Based on the findings from the literature, we suggest that student success in the classroom versus the clinic is based on a different set of variables. Given the range of positions and general lack of reliability and validity in studies of non-cognitive admissions attributes, we think that health professions admissions processes remain imperfect works in progress. PMID:24810020

Least cost pathways to a low carbon electricity system for Australia: impacts of transmission augmentation and extension

NASA Astrophysics Data System (ADS)

Dargaville, R. J.

2016-12-01

Designing the pathway to a low carbon energy system is complex, requiring consideration of the variable nature of renewables at the hourly timescale, emission intensity and ramp rate constraints of dispatchable technologies (both fossil and renewable) and transmission and distribution network limitations. In this work, an optimization framework taking into account these considerations has been applied to find the lowest cost ways to reduce carbon emissions by either 80% or 100% in 2050 while keeping the system operating reliably along the way. Technologies included are existing and advanced coal and gas technologies (with and without carbon capture and storage), rooftop PV, utility scale PV, concentrating solar thermal, hydro with and without pumped storage, bioenergy, and nuclear. In this study we also also the optimisation to increase transmission capacity along existing lines, and to extend key trunk lines into currently unserved areas. These augementations and extensions come at a cost. The otpimisation chooses these options when the benefits of accessing high quality renewable energy resources outweights the costs. Results show that for the 80% emission reduction case, there is limited need for transmission capacity increase, and that the existing grid copes well with the increased flows due to conversion to distrubuted renewable energy resources. However, in the 100% case the increased reliance on renewables means that signficant transmission augmentation is beneficial to the overall cost. This strongly suggests that it is important to understand the long term emission target early so that infrastructure investments can be optimised.

Secondary Students' Considerations of Variability in Measurement Activities Based on Authentic Practices

ERIC Educational Resources Information Center

Dierdorp, Adri; Bakker, Arthur; Ben-Zvi, Dani; Makar, Katie

2017-01-01

Measurement activities were designed in this study on the basis of authentic professional practices in which linear regression is used, to study considerations of variability by students in Grade 12 (aged 17-18). The question addressed in this article is: In what ways do secondary students consider variability within these measurement activities?…

Influence of precipitation and crop germination on resource selection by mule deer (Odocoileus hemionus) in southwest Colorado

USGS Publications Warehouse

Carrollo, Emily M.; Johnson, Heather E.; Fischer, Justin W.; Hammond, Matthew; Dorsey, Patricia D.; Anderson, Charles; Vercauteren, Kurt C.; Walter, W. David

2017-01-01

Mule deer (Odocoileus hemionus) populations in the western United States provide many benefits to local economies but can also cause considerable damage to agriculture, particularly damage to lucrative crops. Limited information exists to understand resource selection of mule deer in response to annual variation in crop rotation and climatic conditions. We tested the hypothesis that mule deer select certain crops, and in particular sunflower, based on annual climatic variability. Our objective was to use movements, estimates of home range, and resource selection analysis to identify resources selected by mule deer. We used annually-derived crop-specific datasets along with Global Positioning System collars to monitor 14 mule deer in an agricultural area near public lands in southwestern Colorado, USA. We estimated home ranges for two winter seasons that ranged between 7.68 and 9.88 km2, and for two summer seasons that ranged between 5.51 and 6.24 km2. Mule deer selected areas closer to forest and alfalfa for most periods during 2012, but selected areas closer to sunflower in a majority of periods during 2013. Considerable annual variation in climate patterns and precipitation levels appeared to influence selection by mule deer because of variability in crop rotation and success of germination of specific crops.

Influence of Precipitation and Crop Germination on Resource Selection by Mule Deer (Odocoileus hemionus) in Southwest Colorado.

PubMed

Carrollo, Emily M; Johnson, Heather E; Fischer, Justin W; Hammond, Matthew; Dorsey, Patricia D; Anderson, Charles; Vercauteren, Kurt C; Walter, W David

2017-11-09

Mule deer (Odocoileus hemionus) populations in the western United States provide many benefits to local economies but can also cause considerable damage to agriculture, particularly damage to lucrative crops. Limited information exists to understand resource selection of mule deer in response to annual variation in crop rotation and climatic conditions. We tested the hypothesis that mule deer select certain crops, and in particular sunflower, based on annual climatic variability. Our objective was to use movements, estimates of home range, and resource selection analysis to identify resources selected by mule deer. We used annually-derived crop-specific datasets along with Global Positioning System collars to monitor 14 mule deer in an agricultural area near public lands in southwestern Colorado, USA. We estimated home ranges for two winter seasons that ranged between 7.68 and 9.88 km 2 , and for two summer seasons that ranged between 5.51 and 6.24 km 2 . Mule deer selected areas closer to forest and alfalfa for most periods during 2012, but selected areas closer to sunflower in a majority of periods during 2013. Considerable annual variation in climate patterns and precipitation levels appeared to influence selection by mule deer because of variability in crop rotation and success of germination of specific crops.

Identifying and assessing the substance-exposed infant.

PubMed

Clark, Lisa; Rohan, Annie

2015-01-01

As the rate of opioid prescription grows, so does fetal exposure to opioids during pregnancy. With increasing fetal exposure to both prescription and nonprescription drugs, there has been a concurrent increase in identification of Neonatal Withdrawal Syndrome (NWS) and adaptation difficulties after birth. In addition, extended use of opioids, barbiturates, and benzodiazepines in neonatal intensive care has resulted in iatrogenic withdrawal syndromes. There is a lack of evidence to support the use of any one specific evaluation strategy to identify NWS. Clinicians caring for infants must use a multimethod approach to diagnosis, including interview and toxicology screening. Signs of NWS are widely variable, and reflect dysfunction in autonomic regulation, state control, and sensory and motor functioning. Several assessment tools have been developed for assessing severity of withdrawal in term neonates. These tools assist in determining need and duration of pharmacologic therapy and help in titration of these therapies. Considerable variability exists in the pharmacologic and nonpharmacologic approaches to affected babies across settings. An evidence-based protocol for identification, evaluation, and management of NWS should be in place in every nursery. This article provides an overview of identification and assessment considerations for providers who care for babies at risk for or who are experiencing alterations in state, behavior, and responses after prenatal or iatrogenic exposure to agents associated with the spectrum of withdrawal.

Missing variables: how exclusion of human resources policy information confounds research connecting health and business outcomes.

PubMed

Lynch, Wendy D; Sherman, Bruce W

2014-01-01

When corporate health researchers examine the effects of health on business outcomes or the effect of health interventions on health and business outcomes, results will necessarily be confounded by the corporate environment(s) in which they are studied. In this research setting, most studies control for factors traditionally identified in public health, such as demographics and health status. Nevertheless, often overlooked is the extent to which company policies can also independently impact health care cost, work attendance, and productivity outcomes. With changes in employment and benefits practices resulting from health care reform, including incentives and plan design options, consideration of these largely neglected variables in research design has become increasingly important. This commentary summarizes existing knowledge regarding the implications of policy variations in research outcomes and provides a framework for incorporating them into future employer-based research.

Determining hospital performance based on rank ordering: is it appropriate?

PubMed

Anderson, Judy; Hackman, Mark; Burnich, Jeff; Gurgiolo, Thomas R

2007-01-01

An increasing number of "pay for performance" initiatives for hospitals and physicians ascribe performance by ranking hospitals or physicians on quality of care measures. Payment is subsequently based on where a hospital or physician ranks among peers. This study examines the variability of ranking hospitals on quality of care measures and its impact on comparing hospital performance. Variability in the ranks of 3 quality of care measures was examined: discharge instruction for congestive heart failure, use of beta-blockers at discharge for heart attack, and timing of initial antibiotic therapy within 4 hours of admission to the hospital for pneumonia. The data are available on the Centers for Medicare and Medicaid Services Web site as part of the Hospital Quality Alliance project. We found that considerable uncertainty exists in ranking of hospitals on these measures, which calls into question the use of rank ordering as a determinant of performance.

Planar attitude motion of a satellite with a variable mass distribution in field of gravity of attracting center

NASA Astrophysics Data System (ADS)

Burov, Alexander; Kosenko, Ivan

2018-05-01

Dynamics of a spacecraft with a variable mass distribution in a central field of Newtonian attraction is considered. Using another viewpoint one can regard sufficiently compact formation instead of a spacecraft. This formation can vary distances between its particular spacecrafts thus implementing pulsing motions of the system as a whole. Within the so-called "satellite approximation" the equations of spatial attitude motion are obtained. Rules of the mass redistribution providing prescribed in advance attitude motions are indicated. For classes of relative equilibria previously found and existing under appropriate rules of the mass redistribution, stability study is performed. The investigation splits into two topics: (a) general dynamical consideration for the planar attitude satellite motion with use of the KAM theory; (b) constructing the families of periodic solutions represented by means of convergent series in powers of eccentricity and describing satellite motions emanating from its relative equilibria.

Natural gas treating with molecular sieves. Pt. 2. Regeneration, economics

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

Harris, T.B.

1972-08-01

Regeneration considerations are often the key to successful and economical application of molecular sieves for natural gas sweetening. In effect, molecular sieves remove the sulfur compounds from the feed stream and concentrate them into a smaller regeneration gas stream. Because a molecular sieve natural gas sweetener concentrates the hydrogen sulfide from the feed stream in a smaller regeneration gas stream, the sulfur-rich gas must be subsequently treated or disposed of. Molecular sieve sweeteners afford a high degree of flexibility in operating rates. They have a very high turndown ratio limited only by the use of product gas for regeneration, whichmore » can be utilized to full advantage with a control system that provides variable cycle times. Tabular data provide a range of designed conditions for existing molecular sieve natural gas sweeteners. Actual operating experience has shown that, in most cases, the following economical advantages can be realized: (1) investment cost is competitive to alternate forms of gas treating; (2) operating cost of molecular sieve units are generally lower (3) the value of carbon dioxide left in natural gas can lead to a considerable operating credit; and (4) the incremental costs of expansion to an existing plant are normally much less. (24 refs.)« less

Reconsidering formative measurement.

PubMed

Howell, Roy D; Breivik, Einar; Wilcox, James B

2007-06-01

The relationship between observable responses and the latent constructs they are purported to measure has received considerable attention recently, with particular focus on what has become known as formative measurement. This alternative to reflective measurement in the area of theory-testing research is examined in the context of the potential for interpretational confounding and a construct's ability to function as a point variable within a larger model. Although these issues have been addressed in the traditional reflective measurement context, the authors suggest that they are particularly relevant in evaluating formative measurement models. On the basis of this analysis, the authors conclude that formative measurement is not an equally attractive alternative to reflective measurement and that whenever possible, in developing new measures or choosing among alternative existing measures, researchers should opt for reflective measurement. In addition, the authors provide guidelines for researchers dealing with existing formative measures. Copyright 2007 APA, all rights reserved.

Structural Optimization of a Knuckle with Consideration of Stiffness and Durability Requirements

PubMed Central

Kim, Geun-Yeon

2014-01-01

The automobile's knuckle is connected to the parts of the steering system and the suspension system and it is used for adjusting the direction of a rotation through its attachment to the wheel. This study changes the existing material made of GCD45 to Al6082M and recommends the lightweight design of the knuckle as the optimal design technique to be installed in small cars. Six shape design variables were selected for the optimization of the knuckle and the criteria relevant to stiffness and durability were considered as the design requirements during the optimization process. The metamodel-based optimization method that uses the kriging interpolation method as the optimization technique was applied. The result shows that all constraints for stiffness and durability are satisfied using A16082M, while reducing the weight of the knuckle by 60% compared to that of the existing GCD450. PMID:24995359

Optimizing the benefits of exercise on physical function in older adults.

PubMed

Buford, Thomas W; Anton, Stephen D; Clark, David J; Higgins, Torrance J; Cooke, Matthew B

2014-06-01

As the number of older adults continues to rise worldwide, the prevention of physical disability among seniors is an increasingly important public health priority. Physical exercise is among the best known methods of preventing disability, but accumulating evidence indicates that considerable variability exists in the responsiveness of older adults to standard training regimens. Accordingly, a need exists to develop tailored interventions to optimize the beneficial effects of exercise on the physical function of older adults at risk for becoming disabled. The present review summarizes the available literature related to the use of adjuvant or alternative strategies intended to enhance the efficacy of exercise in improving the physical function of older adults. Within this work, we also discuss potential future research directions in this area. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

A study of the compatibility of an existing CFD package with a broader class of material constitutions

NASA Technical Reports Server (NTRS)

French, K. W., Jr.

1985-01-01

The flexibility of the PHOENICS computational fluid dynamics package was assessed along two general avenues; parallel modeling and analog modeling. In parallel modeling the dependent and independent variables retain their identity within some scaling factors, even though the boundary conditions and especially the constitutive relations do not correspond to any realistic fluid dynamic situation. PHOENICS was used to generate a CFD model that should exhibit the physical anomalies of a granular medium and permit reasonable similarity with boundary conditions typical to membrane or porous piston loading. A considerable portion of the study was spent prying into the existing code with a prejudice toward rate type and disarming any inherent fluid behavior. The final stages of the study were directed at the more specific problem of multiaxis loading of cylindrical geometry with a concern for the appearance of bulging, cross slab shear failure modes.

Human Milk and Allergic Diseases: An Unsolved Puzzle

PubMed Central

Peroni, Diego G.; Boix-Amorós, Alba; Hsu, Peter S.; Van’t Land, Belinda; Skevaki, Chrysanthi; Collado, Maria Carmen; Garssen, Johan; Geddes, Donna T.; Nanan, Ralph; Slupsky, Carolyn; Wegienka, Ganesa; Kozyrskyj, Anita L.; Warner, John O.

2017-01-01

There is conflicting evidence on the protective role of breastfeeding in relation to the development of allergic sensitisation and allergic disease. Studies vary in methodology and definition of outcomes, which lead to considerable heterogeneity. Human milk composition varies both within and between individuals, which may partially explain conflicting data. It is known that human milk composition is very complex and contains variable levels of immune active molecules, oligosaccharides, metabolites, vitamins and other nutrients and microbial content. Existing evidence suggests that modulation of human breast milk composition has potential for preventing allergic diseases in early life. In this review, we discuss associations between breastfeeding/human milk composition and allergy development. PMID:28817095

Human Milk and Allergic Diseases: An Unsolved Puzzle.

PubMed

Munblit, Daniel; Peroni, Diego G; Boix-Amorós, Alba; Hsu, Peter S; Van't Land, Belinda; Gay, Melvin C L; Kolotilina, Anastasia; Skevaki, Chrysanthi; Boyle, Robert J; Collado, Maria Carmen; Garssen, Johan; Geddes, Donna T; Nanan, Ralph; Slupsky, Carolyn; Wegienka, Ganesa; Kozyrskyj, Anita L; Warner, John O

2017-08-17

There is conflicting evidence on the protective role of breastfeeding in relation to the development of allergic sensitisation and allergic disease. Studies vary in methodology and definition of outcomes, which lead to considerable heterogeneity. Human milk composition varies both within and between individuals, which may partially explain conflicting data. It is known that human milk composition is very complex and contains variable levels of immune active molecules, oligosaccharides, metabolites, vitamins and other nutrients and microbial content. Existing evidence suggests that modulation of human breast milk composition has potential for preventing allergic diseases in early life. In this review, we discuss associations between breastfeeding/human milk composition and allergy development.

Reactor pressure vessel embrittlement: Insights from neural network modelling

NASA Astrophysics Data System (ADS)

Mathew, J.; Parfitt, D.; Wilford, K.; Riddle, N.; Alamaniotis, M.; Chroneos, A.; Fitzpatrick, M. E.

2018-04-01

Irradiation embrittlement of steel pressure vessels is an important consideration for the operation of current and future light water nuclear reactors. In this study we employ an ensemble of artificial neural networks in order to provide predictions of the embrittlement using two literature datasets, one based on US surveillance data and the second from the IVAR experiment. We use these networks to examine trends with input variables and to assess various literature models including compositional effects and the role of flux and temperature. Overall, the networks agree with the existing literature models and we comment on their more general use in predicting irradiation embrittlement.

A design procedure for the handling qualities optimization of the X-29A aircraft

NASA Technical Reports Server (NTRS)

Bosworth, John T.; Cox, Timothy H.

1989-01-01

The techniques used to improve the pitch-axis handling qualities of the X-29A wing-canard-planform fighter aircraft are reviewed. The aircraft and its FCS are briefly described, and the design method, which works within the existing FCS architecture, is characterized in detail. Consideration is given to the selection of design goals and design variables, the definition and calculation of the cost function, the validation of the mathematical model on the basis of flight-test data, and the validation of the improved design by means of nonlinear simulations. Flight tests of the improved design are shown to verify the simulation results.

Von recklinghausens disease: a series of four cases with variable expression.

PubMed

Arun, K P; Thomas Joseph, P; Jaishankar, H P; Abhinethra, M S

2015-03-01

Though neurofibromatosis type I (NFI) is a fairly common condition, it has a variable expressivity and penetrance. Here we present a series of cases with striking differences in the presentation especially in the oral cavity. NFI, also known as von Recklinghausen's neurofibromatosis, is an autosomal dominantly inherited neurogenetic disorder affecting 1:3000 newborn (Bongiorno et al., Oral Dis 12:125-129, 2006). About 50 % of NFI patients have no family history of the disease. There is no prevalence for gender or race in NFI. Expressivity in NFI is tremendously variable, but subtle phenotypic patterns may exist within subgroups of affected patients. Furthermore, 50 % of cases are sporadic and arise from germ cell mutation (Bongiorno et al., Oral Dis 12:125-129, 2006). The precise constellation of findings in any one individual is extremely variable, both within a family and between different families (Batsakis, Tumors of the head and neck: clinical and pathological considerations, 2nd edn. Williams and Wilkins, Baltimore, pp 313-333, 1979). Only 4-7 % of patients affected by neurofibromatosis exhibit oral manifestations (Güneri et al., Turk J Pediatr 48(2):155-158, 2006).

Novel Biomarkers for Predicting Cardiovascular Disease in Patients With Diabetes.

PubMed

Retnakaran, Ravi

2018-05-01

It is generally acknowledged that patients with diabetes comprise a high-risk population for the development of cardiovascular disease. However, it is perhaps less well recognized that there actually exists considerable heterogeneity in vascular risk within this patient population, with a sizable subset of individuals seemingly at low risk for major cardiovascular events despite the presence of diabetes. Because traditional clinical risk calculators have shown wide variability in their performance in the setting of diabetes, there exists a need for additional risk predictors in this patient population. In this context, there has been considerable interest in the potential utility of circulating biomarkers as clinical tools that might facilitate risk stratification and thereby guide therapeutic and preventative decision-making. Coupled with the current era of dedicated cardiovascular outcome trials in type 2 diabetes, this interest has spawned a growing literature of recent studies that evaluated potential biomarkers. To date, these studies have identified N-terminal pro-B-type natriuretic peptide, high-sensitivity cardiac troponins, and growth differentiation factor-15 as cardiovascular biomarkers of particular potential in patients with diabetes. Furthermore, recognizing the potential benefit of collective consideration of different biomarkers reflecting distinct pathophysiologic processes that might contribute to the development of cardiovascular disease, there is emerging emphasis on the evaluation of combinations of biomarkers for optimal risk prediction. Although not currently ready for clinical practice, this rapidly-growing topic of biomarker research might ultimately facilitate the goal of individualized risk stratification and thereby enable truly personalized management of diabetes. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

The temperature size rule in arthropods: independent of macro-environmental variables but size dependent.

PubMed

Klok, C Jaco; Harrison, Jon F

2013-10-01

Temperature is a key factor that affects the rates of growth and development in animals, which ultimately determine body size. Although not universal, a widely documented and poorly understood pattern is the inverse relationship between the temperature at which an ectothermic animal is reared and its body size (temperature size rule [TSR]). The proximate and ultimate mechanisms for the TSR remain unclear. To explore possible explanations for the TSR, we tested for correlations between the magnitude/direction of the TSR and latitude, temperature, elevation, habitat, availability of oxygen, capacity for flight, and taxonomic grouping in 98 species/populations of arthropods. The magnitude and direction of the TSR was not correlated with any of the macro-environmental variables we examined, supporting the generality of the TSR. However, body size affected the magnitude and direction of the TSR, with smaller arthropods more likely to demonstrate a classic TSR. Considerable variation among species exists in the TSR, suggesting either strong interactions with nutrition, or selection based on microclimatic or seasonal variation not captured in classic macro-environmental variables.

A special protection scheme utilizing trajectory sensitivity analysis in power transmission

NASA Astrophysics Data System (ADS)

Suriyamongkol, Dan

In recent years, new measurement techniques have provided opportunities to improve the North American Power System observability, control and protection. This dissertation discusses the formulation and design of a special protection scheme based on a novel utilization of trajectory sensitivity techniques with inputs consisting of system state variables and parameters. Trajectory sensitivity analysis (TSA) has been used in previous publications as a method for power system security and stability assessment, and the mathematical formulation of TSA lends itself well to some of the time domain power system simulation techniques. Existing special protection schemes often have limited sets of goals and control actions. The proposed scheme aims to maintain stability while using as many control actions as possible. The approach here will use the TSA in a novel way by using the sensitivities of system state variables with respect to state parameter variations to determine the state parameter controls required to achieve the desired state variable movements. The initial application will operate based on the assumption that the modeled power system has full system observability, and practical considerations will be discussed.

Considerations in the statistical analysis of clinical trials in periodontitis.

PubMed

Imrey, P B

1986-05-01

Adult periodontitis has been described as a chronic infectious process exhibiting sporadic, acute exacerbations which cause quantal, localized losses of dental attachment. Many analytic problems of periodontal trials are similar to those of other chronic diseases. However, the episodic, localized, infrequent, and relatively unpredictable behavior of exacerbations, coupled with measurement error difficulties, cause some specific problems. Considerable controversy exists as to the proper selection and treatment of multiple site data from the same patient for group comparisons for epidemiologic or therapeutic evaluative purposes. This paper comments, with varying degrees of emphasis, on several issues pertinent to the analysis of periodontal trials. Considerable attention is given to the ways in which measurement variability may distort analytic results. Statistical treatments of multiple site data for descriptive summaries are distinguished from treatments for formal statistical inference to validate therapeutic effects. Evidence suggesting that sites behave independently is contested. For inferential analyses directed at therapeutic or preventive effects, analytic models based on site independence are deemed unsatisfactory. Methods of summarization that may yield more powerful analyses than all-site mean scores, while retaining appropriate treatment of inter-site associations, are suggested. Brief comments and opinions on an assortment of other issues in clinical trial analysis are preferred.

An approximately Bayesian delta-rule model explains the dynamics of belief updating in a changing environment.

PubMed

Nassar, Matthew R; Wilson, Robert C; Heasly, Benjamin; Gold, Joshua I

2010-09-15

Maintaining appropriate beliefs about variables needed for effective decision making can be difficult in a dynamic environment. One key issue is the amount of influence that unexpected outcomes should have on existing beliefs. In general, outcomes that are unexpected because of a fundamental change in the environment should carry more influence than outcomes that are unexpected because of persistent environmental stochasticity. Here we use a novel task to characterize how well human subjects follow these principles under a range of conditions. We show that the influence of an outcome depends on both the error made in predicting that outcome and the number of similar outcomes experienced previously. We also show that the exact nature of these tendencies varies considerably across subjects. Finally, we show that these patterns of behavior are consistent with a computationally simple reduction of an ideal-observer model. The model adjusts the influence of newly experienced outcomes according to ongoing estimates of uncertainty and the probability of a fundamental change in the process by which outcomes are generated. A prior that quantifies the expected frequency of such environmental changes accounts for individual variability, including a positive relationship between subjective certainty and the degree to which new information influences existing beliefs. The results suggest that the brain adaptively regulates the influence of decision outcomes on existing beliefs using straightforward updating rules that take into account both recent outcomes and prior expectations about higher-order environmental structure.

Optimization of agricultural field workability predictions for improved risk management

USDA-ARS?s Scientific Manuscript database

Risks introduced by weather variability are key considerations in agricultural production. The sensitivity of agriculture to weather variability is of special concern in the face of climate change. In particular, the availability of workable days is an important consideration in agricultural practic...

Regenerative life support system research

NASA Technical Reports Server (NTRS)

1988-01-01

Sections on modeling, experimental activities during the grant period, and topics under consideration for the future are contained. The sessions contain discussions of: four concurrent modeling approaches that were being integrated near the end of the period (knowledge-based modeling support infrastructure and data base management, object-oriented steady state simulations for three concepts, steady state mass-balance engineering tradeoff studies, and object-oriented time-step, quasidynamic simulations of generic concepts); interdisciplinary research activities, beginning with a discussion of RECON lab development and use, and followed with discussions of waste processing research, algae studies and subsystem modeling, low pressure growth testing of plants, subsystem modeling of plants, control of plant growth using lighting and CO2 supply as variables, search for and development of lunar soil simulants, preliminary design parameters for a lunar base life support system, and research considerations for food processing in space; and appendix materials, including a discussion of the CELSS Conference, detailed analytical equations for mass-balance modeling, plant modeling equations, and parametric data on existing life support systems for use in modeling.

Consideration of measurement error when using commercial indoor radon determinations for selecting radon action levels

USGS Publications Warehouse

Reimer, G.M.; Szarzi, S.L.; Dolan, Michael P.

1998-01-01

An examination of year-long, in-home radon measurement in Colorado from commercial companies applying typical methods indicates that considerable variation in precision exists. This variation can have a substantial impact on any mitigation decisions, either voluntary or mandated by law, especially regarding property sale or exchange. Both long-term exposure (nuclear track greater than 90 days), and short-term (charcoal adsorption 4-7 days) exposure methods were used. In addition, periods of continuous monitoring with a highly calibrated alpha-scintillometer took place for accuracy calibration. The results of duplicate commercial analysis show that typical results are no better than ??25 percent with occasional outliers (up to 5 percent of all analyses) well beyond that limit. Differential seasonal measurements (winter/summer) by short-term methods provide equivalent information to single long-term measurements. Action levels in the U.S. for possible mitigation decisions should be selected so that they consider the measurement variability; specifically, they should reflect a concentration range similar to that adopted by the European Community.

Immunization information systems in Canada: Attributes, functionality, strengths and challenges. A Canadian Immunization Research Network study.

PubMed

Wilson, Sarah E; Quach, Susan; MacDonald, Shannon E; Naus, Monika; Deeks, Shelley L; Crowcroft, Natasha S; Mahmud, Salaheddin M; Tran, Dat; Kwong, Jeffrey C; Tu, Karen; Johnson, Caitlin; Desai, Shalini

2017-03-01

Canada does not have a national immunization registry. Diverse systems to record vaccine uptake exist, but these have not been systematically described. Our objective was to describe the immunization information systems (IISs) and non-IIS processes used to record childhood and adolescent vaccinations, and to outline the strengths and limitations of the systems and processes. We collected information from key informants regarding their provincial, territorial or federal organization's surveillance systems for assessing immunization coverage. Information collection consisted of a self-administered questionnaire and a follow-up interview. We evaluated systems against attributes derived from the literature using content analysis. Twenty-six individuals across 16 public health organizations participated over the period of April to August 2015. Twelve of Canada's 13 provinces and territories (P/Ts) and two organizations involved in health service delivery for on-reserve First Nations people participated. Across systems, there were differences in data collection processes, reporting capabilities and advanced functionality. Commonly cited challenges included timeliness and data completeness of records, particularly for physician-administered immunizations. Privacy considerations and the need for data standards were stated as challenges to the goal of information sharing across P/T systems. Many P/Ts have recently implemented new systems and, in some cases, legislation to improve timeliness and/or completeness. Considerable variability exists among IISs and non-IIS processes used to assess immunization coverage in Canada. Although some P/Ts have already pursued legislative or policy initiatives to address the completeness and timeliness of information, many additional opportunities exist in the information technology realm.

Real-Time Alpine Measurement System Using Wireless Sensor Networks

PubMed Central

2017-01-01

Monitoring the snow pack is crucial for many stakeholders, whether for hydro-power optimization, water management or flood control. Traditional forecasting relies on regression methods, which often results in snow melt runoff predictions of low accuracy in non-average years. Existing ground-based real-time measurement systems do not cover enough physiographic variability and are mostly installed at low elevations. We present the hardware and software design of a state-of-the-art distributed Wireless Sensor Network (WSN)-based autonomous measurement system with real-time remote data transmission that gathers data of snow depth, air temperature, air relative humidity, soil moisture, soil temperature, and solar radiation in physiographically representative locations. Elevation, aspect, slope and vegetation are used to select network locations, and distribute sensors throughout a given network location, since they govern snow pack variability at various scales. Three WSNs were installed in the Sierra Nevada of Northern California throughout the North Fork of the Feather River, upstream of the Oroville dam and multiple powerhouses along the river. The WSNs gathered hydrologic variables and network health statistics throughout the 2017 water year, one of northern Sierra’s wettest years on record. These networks leverage an ultra-low-power wireless technology to interconnect their components and offer recovery features, resilience to data loss due to weather and wildlife disturbances and real-time topological visualizations of the network health. Data show considerable spatial variability of snow depth, even within a 1 km2 network location. Combined with existing systems, these WSNs can better detect precipitation timing and phase in, monitor sub-daily dynamics of infiltration and surface runoff during precipitation or snow melt, and inform hydro power managers about actual ablation and end-of-season date across the landscape. PMID:29120376

Real-Time Alpine Measurement System Using Wireless Sensor Networks.

PubMed

Malek, Sami A; Avanzi, Francesco; Brun-Laguna, Keoma; Maurer, Tessa; Oroza, Carlos A; Hartsough, Peter C; Watteyne, Thomas; Glaser, Steven D

2017-11-09

Monitoring the snow pack is crucial for many stakeholders, whether for hydro-power optimization, water management or flood control. Traditional forecasting relies on regression methods, which often results in snow melt runoff predictions of low accuracy in non-average years. Existing ground-based real-time measurement systems do not cover enough physiographic variability and are mostly installed at low elevations. We present the hardware and software design of a state-of-the-art distributed Wireless Sensor Network (WSN)-based autonomous measurement system with real-time remote data transmission that gathers data of snow depth, air temperature, air relative humidity, soil moisture, soil temperature, and solar radiation in physiographically representative locations. Elevation, aspect, slope and vegetation are used to select network locations, and distribute sensors throughout a given network location, since they govern snow pack variability at various scales. Three WSNs were installed in the Sierra Nevada of Northern California throughout the North Fork of the Feather River, upstream of the Oroville dam and multiple powerhouses along the river. The WSNs gathered hydrologic variables and network health statistics throughout the 2017 water year, one of northern Sierra's wettest years on record. These networks leverage an ultra-low-power wireless technology to interconnect their components and offer recovery features, resilience to data loss due to weather and wildlife disturbances and real-time topological visualizations of the network health. Data show considerable spatial variability of snow depth, even within a 1 km 2 network location. Combined with existing systems, these WSNs can better detect precipitation timing and phase in, monitor sub-daily dynamics of infiltration and surface runoff during precipitation or snow melt, and inform hydro power managers about actual ablation and end-of-season date across the landscape.

Supporting children facing a parent's cancer diagnosis: a systematic review of children's psychosocial needs and existing interventions.

PubMed

Ellis, S J; Wakefield, C E; Antill, G; Burns, M; Patterson, P

2017-01-01

This review aimed to (1) summarise the psychosocial needs of children/adolescents (0-18 years) with a parent with cancer across the illness trajectory (diagnosis to bereavement) and (2) evaluate existing interventions for this population. Medline, CINAHL, PsychInfo, EMBASE and Social Work Abstracts were systematically searched for articles published from 1985 to 2015. Of 98 full text articles retrieved, 12 reported on children's psychosocial needs, and 12 intervention studies were identified. Each article was appraised in accordance with the Mixed Method Appraisal Tool. Three factors emerged as critical to consider in future intervention development: (1) Children need age-appropriate information about their parent's cancer; (2) Children require support communicating with parents, family members and health professionals and (3) Children need an environment where they feel comfortable sharing positive/negative emotions and can have their experiences normalised among peers. All intervention studies reported at least one positive outcome, however, only five reported significant improvements in child/family functioning based on validated quantitative measure/s. Variability in study design and quality, combined with considerable heterogeneity in intervention characteristics and outcome variables limited the conclusions, which could be drawn. Therefore, further carefully designed and scientifically evaluated interventions for children facing a parent's cancer diagnosis are clearly warranted. © 2016 John Wiley & Sons Ltd.

Male recombination in Brazilian populations of Drosophila ananassae.

PubMed

Goñi, Beatriz; Matsuda, Muneo; Tobari, Yoshiko N

2016-07-01

With few exceptions, spontaneous crossing over does not normally occur in male Drosophila. Drosophila ananassae males show considerable amounts of crossing over. In wild males of D. ananassae from Asian (2008) and Brazilian populations (1986 and 2007) variable frequencies of meiotic crossing over, estimated from chiasmata counts, suggested the existence of factors controlling male crossing over in these populations. To corroborate for such prediction, we present data on spontaneous recombination in F1 males of D. ananassae heterozygous for chromosomes of the same Brazilian populations (1986) and marker chromosomes using three testers stocks. Mean recombination value was low, although high variability existed between individual frequencies. Recombination frequencies between lines in each tester stock were not significantly different, excepting when the 3ple-px and 3ple-cy testers were compared (p < 0.05). These two testers differ in respect to the regional distribution of crossovers. The occurrence of recombination in chromosomes 2 and 3 in F1 males tested with e(65) se; bri ru was not related, suggesting they are under independent genetic control. Our data are consistent with proposed genetic factors controlling male crossing over in the tester stocks and to the presence of enhancers and suppressors of male crossing over segregating in the Brazilian populations (1986).

SSAGES: Software Suite for Advanced General Ensemble Simulations

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

Sidky, Hythem; Colón, Yamil J.; Helfferich, Julian

Molecular simulation has emerged as an essential tool for modern-day research, but obtaining proper results and making reliable conclusions from simulations requires adequate sampling of the system under consideration. To this end, a variety of methods exist in the literature that can enhance sampling considerably, and increasingly sophisticated, effective algorithms continue to be developed at a rapid pace. Implementation of these techniques, however, can be challenging for experts and non-experts alike. There is a clear need for software that provides rapid, reliable, and easy access to a wide range of advanced sampling methods, and that facilitates implementation of new techniquesmore » as they emerge. Here we present SSAGES, a publicly available Software Suite for Advanced General Ensemble Simulations designed to interface with multiple widely used molecular dynamics simulations packages. SSAGES allows facile application of a variety of enhanced sampling techniques—including adaptive biasing force, string methods, and forward flux sampling—that extract meaningful free energy and transition path data from all-atom and coarse grained simulations. A noteworthy feature of SSAGES is a user-friendly framework that facilitates further development and implementation of new methods and collective variables. In this work, the use of SSAGES is illustrated in the context of simple representative applications involving distinct methods and different collective variables that are available in the current release of the suite.« less

Design of Maternity Pillow by Using Kansei and Taguchi Methods

NASA Astrophysics Data System (ADS)

Ilma Rahmillah, Fety; Nanda kartika, Rachmah

2017-06-01

One of the customers’ considerations for purchasing a product is it can satisfy their feeling and emotion. It because of such product can enhance sleep quality of pregnant women. However, most of the existing product such as maternity pillows are still designed based on companies’ perspective. This study aims to capture the desire of pregnant women toward maternity pillow desired product by using kansei words and analyze the optimal design with Taguchi method. Eight collected kansei words were durable, aesthetic, comfort, portable, simple, multifunction, attractive motive, and easy to maintain. While L16 orthogonal array is used because there are three variables with two levels and four variables with four levels. It can be concluded that the best maternity pillow that can satisfy the customers can be designed by combining D1-E2-F2-G2-C1-B2-A2 means the model is U shape, flowery motive, medium color, Bag model B, cotton pillow cover, filled with silicon, and use double zipper. However, it is also possible to create combination of D1-E2-F2-G2-C1-B1-A1 by using consideration of cost which means that the zipper is switched to single as well as filled with dacron. In addition, the total percentage of contribution by using ANOVA reaches 95%.

SSAGES: Software Suite for Advanced General Ensemble Simulations.

PubMed

Sidky, Hythem; Colón, Yamil J; Helfferich, Julian; Sikora, Benjamin J; Bezik, Cody; Chu, Weiwei; Giberti, Federico; Guo, Ashley Z; Jiang, Xikai; Lequieu, Joshua; Li, Jiyuan; Moller, Joshua; Quevillon, Michael J; Rahimi, Mohammad; Ramezani-Dakhel, Hadi; Rathee, Vikramjit S; Reid, Daniel R; Sevgen, Emre; Thapar, Vikram; Webb, Michael A; Whitmer, Jonathan K; de Pablo, Juan J

2018-01-28

Molecular simulation has emerged as an essential tool for modern-day research, but obtaining proper results and making reliable conclusions from simulations requires adequate sampling of the system under consideration. To this end, a variety of methods exist in the literature that can enhance sampling considerably, and increasingly sophisticated, effective algorithms continue to be developed at a rapid pace. Implementation of these techniques, however, can be challenging for experts and non-experts alike. There is a clear need for software that provides rapid, reliable, and easy access to a wide range of advanced sampling methods and that facilitates implementation of new techniques as they emerge. Here we present SSAGES, a publicly available Software Suite for Advanced General Ensemble Simulations designed to interface with multiple widely used molecular dynamics simulations packages. SSAGES allows facile application of a variety of enhanced sampling techniques-including adaptive biasing force, string methods, and forward flux sampling-that extract meaningful free energy and transition path data from all-atom and coarse-grained simulations. A noteworthy feature of SSAGES is a user-friendly framework that facilitates further development and implementation of new methods and collective variables. In this work, the use of SSAGES is illustrated in the context of simple representative applications involving distinct methods and different collective variables that are available in the current release of the suite. The code may be found at: https://github.com/MICCoM/SSAGES-public.

SSAGES: Software Suite for Advanced General Ensemble Simulations

NASA Astrophysics Data System (ADS)

Sidky, Hythem; Colón, Yamil J.; Helfferich, Julian; Sikora, Benjamin J.; Bezik, Cody; Chu, Weiwei; Giberti, Federico; Guo, Ashley Z.; Jiang, Xikai; Lequieu, Joshua; Li, Jiyuan; Moller, Joshua; Quevillon, Michael J.; Rahimi, Mohammad; Ramezani-Dakhel, Hadi; Rathee, Vikramjit S.; Reid, Daniel R.; Sevgen, Emre; Thapar, Vikram; Webb, Michael A.; Whitmer, Jonathan K.; de Pablo, Juan J.

2018-01-01

Molecular simulation has emerged as an essential tool for modern-day research, but obtaining proper results and making reliable conclusions from simulations requires adequate sampling of the system under consideration. To this end, a variety of methods exist in the literature that can enhance sampling considerably, and increasingly sophisticated, effective algorithms continue to be developed at a rapid pace. Implementation of these techniques, however, can be challenging for experts and non-experts alike. There is a clear need for software that provides rapid, reliable, and easy access to a wide range of advanced sampling methods and that facilitates implementation of new techniques as they emerge. Here we present SSAGES, a publicly available Software Suite for Advanced General Ensemble Simulations designed to interface with multiple widely used molecular dynamics simulations packages. SSAGES allows facile application of a variety of enhanced sampling techniques—including adaptive biasing force, string methods, and forward flux sampling—that extract meaningful free energy and transition path data from all-atom and coarse-grained simulations. A noteworthy feature of SSAGES is a user-friendly framework that facilitates further development and implementation of new methods and collective variables. In this work, the use of SSAGES is illustrated in the context of simple representative applications involving distinct methods and different collective variables that are available in the current release of the suite. The code may be found at: https://github.com/MICCoM/SSAGES-public.

Vaccine stabilization: research, commercialization, and potential impact.

PubMed

Kristensen, Debra; Chen, Dexiang; Cummings, Ray

2011-09-22

All vaccines are susceptible to damage by elevated temperatures and many are also damaged by freezing. The distribution, storage, and use of vaccines therefore present challenges that could be reduced by enhanced thermostability, with resulting improvements in vaccine effectiveness. Formulation and processing technologies exist that can improve the stability of vaccines at temperature extremes, however, customization is required for individual vaccines and results are variable. Considerations affecting decisions about stabilization approaches include development cost, manufacturing cost, and the ease of use of the final product. Public sector agencies can incentivize vaccine developers to prioritize stabilization efforts through advocacy and by implementing policies that increase demand for thermostable vaccines. Copyright © 2011 Elsevier Ltd. All rights reserved.

Evidence of gravity wave-tidal interaction observed near the summer mesopause at Poker Flat, Alaska

NASA Technical Reports Server (NTRS)

Wang, Ding-Yi; Fritts, David C.

1991-01-01

An analysis of gravity wave-tidal interaction observed near the mesopause by the MST radar at Poker Flat in July of 1986 is presented. The observations revealed daily mean wind maxima of about 60 m/sec westward and 20 m/sec southward with daily mean momentum fluxes, contributed by gravity waves with periods less than 1 hour of 4-5 sq m/sec sq eastward and 1-2 sq m/sec sq northward. Considerable hourly height variability was found to exist for both winds and momentum fluxes. A significant modulation of the fluxes by tidal winds was observed, characterized by out-of-phase correlations over a number of heights.

Quantum cryptography approaching the classical limit.

PubMed

Weedbrook, Christian; Pirandola, Stefano; Lloyd, Seth; Ralph, Timothy C

2010-09-10

We consider the security of continuous-variable quantum cryptography as we approach the classical limit, i.e., when the unknown preparation noise at the sender's station becomes significantly noisy or thermal (even by as much as 10(4) times greater than the variance of the vacuum mode). We show that, provided the channel transmission losses do not exceed 50%, the security of quantum cryptography is not dependent on the channel transmission, and is therefore incredibly robust against significant amounts of excess preparation noise. We extend these results to consider for the first time quantum cryptography at wavelengths considerably longer than optical and find that regions of security still exist all the way down to the microwave.

Lead exposure of the child population in Greece.

PubMed

Maravelias, C; Athanaselis, S; Poulos, L; Alevisopoulos, G; Ewers, U; Koutselinis, A

1994-12-18

Lead exposure of the child population was studied in three different areas in Greece: Kalamata which is a rural area of Southern Greece; Tavros, a district of Athens with a considerable industrial activity; and Lavrion, a small city near Athens where a lead-zinc mining and smelting industrial complex has existed for more than 90 years. The results were evaluated with respect to a number of individual, social and environmental variables (i.e. smelter, occupation of the father) especially those concerning the area of Lavrion which is the most heavily polluted area in Greece. The results of this study can be considered as an index for the extent of the lead pollution problem in the named areas of Greece.

Policies of Academic Medical Centers for Disclosing Conflicts of Interest to Potential Research Participants

PubMed Central

Weinfurt, Kevin P.; Dinan, Michaela A.; Allsbrook, Jennifer S.; Friedman, Joëlle Y.; Hall, Mark A.; Schulman, Kevin A.; Sugarman, Jeremy

2007-01-01

Many professional organizations and governmental bodies recommend disclosing financial conflicts of interest to potential research participants. Three possible goals of such disclosures are to inform the decision making of potential research participants, to protect against liability, and to deter conflicts of interest. We reviewed US academic medical centers' policies regarding the disclosure of conflicts of interest in research. Forty-eight percent mentioned disclosing conflicts to potential research participants. Of those, 58% included verbatim language that could be used in informed consent documents. Considerable variability exists concerning the specific information that should be disclosed. Most of the institutions' policies are consistent with the goal of protection from legal liability. PMID:16436571

Laser system refinements to reduce variability in infarct size in the rat photothrombotic stroke model

PubMed Central

Alaverdashvili, Mariam; Paterson, Phyllis G.; Bradley, Michael P.

2015-01-01

Background The rat photothrombotic stroke model can induce brain infarcts with reasonable biological variability. Nevertheless, we observed unexplained high inter-individual variability despite using a rigorous protocol. Of the three major determinants of infarct volume, photosensitive dye concentration and illumination period were strictly controlled, whereas undetected fluctuation in laser power output was suspected to account for the variability. New method The frequently utilized Diode Pumped Solid State (DPSS) lasers emitting 532 nm (green) light can exhibit fluctuations in output power due to temperature and input power alterations. The polarization properties of the Nd:YAG and Nd:YVO4 crystals commonly used in these lasers are another potential source of fluctuation, since one means of controlling output power uses a polarizer with a variable transmission axis. Thus, the properties of DPSS lasers and the relationship between power output and infarct size were explored. Results DPSS laser beam intensity showed considerable variation. Either a polarizer or a variable neutral density filter allowed adjustment of a polarized laser beam to the desired intensity. When the beam was unpolarized, the experimenter was restricted to using a variable neutral density filter. Comparison with existing method(s) Our refined approach includes continuous monitoring of DPSS laser intensity via beam sampling using a pellicle beamsplitter and photodiode sensor. This guarantees the desired beam intensity at the targeted brain area during stroke induction, with the intensity controlled either through a polarizer or variable neutral density filter. Conclusions Continuous monitoring and control of laser beam intensity is critical for ensuring consistent infarct size. PMID:25840363

Characterizing Individual Differences in Functional Connectivity Using Dual-Regression and Seed-Based Approaches

PubMed Central

Smith, David V.; Utevsky, Amanda V.; Bland, Amy R.; Clement, Nathan; Clithero, John A.; Harsch, Anne E. W.; Carter, R. McKell; Huettel, Scott A.

2014-01-01

A central challenge for neuroscience lies in relating inter-individual variability to the functional properties of specific brain regions. Yet, considerable variability exists in the connectivity patterns between different brain areas, potentially producing reliable group differences. Using sex differences as a motivating example, we examined two separate resting-state datasets comprising a total of 188 human participants. Both datasets were decomposed into resting-state networks (RSNs) using a probabilistic spatial independent components analysis (ICA). We estimated voxelwise functional connectivity with these networks using a dual-regression analysis, which characterizes the participant-level spatiotemporal dynamics of each network while controlling for (via multiple regression) the influence of other networks and sources of variability. We found that males and females exhibit distinct patterns of connectivity with multiple RSNs, including both visual and auditory networks and the right frontal-parietal network. These results replicated across both datasets and were not explained by differences in head motion, data quality, brain volume, cortisol levels, or testosterone levels. Importantly, we also demonstrate that dual-regression functional connectivity is better at detecting inter-individual variability than traditional seed-based functional connectivity approaches. Our findings characterize robust—yet frequently ignored—neural differences between males and females, pointing to the necessity of controlling for sex in neuroscience studies of individual differences. Moreover, our results highlight the importance of employing network-based models to study variability in functional connectivity. PMID:24662574

Determinants of Awareness, Consideration, and Choice Set Size in University Choice.

ERIC Educational Resources Information Center

Dawes, Philip L.; Brown, Jennifer

2002-01-01

Developed and tested a model of students' university "brand" choice using five individual-level variables (ethnic group, age, gender, number of parents going to university, and academic ability) and one situational variable (duration of search) to explain variation in the sizes of awareness, consideration, and choice decision sets. (EV)

Early Childhood Development Cultural Considerations--Commonalities, Variables, and Local Community Determinants for Program Modules.

ERIC Educational Resources Information Center

Taylor, Anne P.; Warren, Dave

The paper discusses cultural commonality and variability considerations of the Native American populations served by the Federation of Rocky Mountain States Educational Technical Development (ETD) Project. Section I explores important factors to consider when setting up an Early Childhood Development program module for Indian people, such as…

Direction dependence analysis: A framework to test the direction of effects in linear models with an implementation in SPSS.

PubMed

Wiedermann, Wolfgang; Li, Xintong

2018-04-16

In nonexperimental data, at least three possible explanations exist for the association of two variables x and y: (1) x is the cause of y, (2) y is the cause of x, or (3) an unmeasured confounder is present. Statistical tests that identify which of the three explanatory models fits best would be a useful adjunct to the use of theory alone. The present article introduces one such statistical method, direction dependence analysis (DDA), which assesses the relative plausibility of the three explanatory models on the basis of higher-moment information about the variables (i.e., skewness and kurtosis). DDA involves the evaluation of three properties of the data: (1) the observed distributions of the variables, (2) the residual distributions of the competing models, and (3) the independence properties of the predictors and residuals of the competing models. When the observed variables are nonnormally distributed, we show that DDA components can be used to uniquely identify each explanatory model. Statistical inference methods for model selection are presented, and macros to implement DDA in SPSS are provided. An empirical example is given to illustrate the approach. Conceptual and empirical considerations are discussed for best-practice applications in psychological data, and sample size recommendations based on previous simulation studies are provided.

Nonsense-mediated mRNA decay: inter-individual variability and human disease

PubMed Central

Nguyen, Lam Son; Wilkinson, Miles; Gecz, Jozef

2013-01-01

Nonsense-Mediated mRNA Decay (NMD) is a regulatory pathway that functions to degrade transcripts containing premature termination codons (PTCs) and to maintain normal transcriptome homeostasis. Nonsense and frameshift mutations that generate PTCs cause approximately one-third of all known human genetic diseases and thus NMD has a potentially important role in human disease. In genetic disorders in which the affected genes carry PTC-generating mutations, NMD acts as a double-edge sword. While it can benefit the patient by degrading PTC-containing mRNAs that encode detrimental, dominant-negative truncated proteins, it can also make the disease worse when a PTC-containing mRNA is degraded that encodes a mutant but still functional protein. There is evidence that the magnitude of NMD varies between individuals, which, in turn, has been shown to correlate with both clinical presentations and the patients’ responses to drugs that promote read-through of PTCs. In this review, we examine the evidence supporting the existence of inter-individual variability in NMD efficiency and discuss the genetic factors that underlie this variability. We propose that inter-individual variability in NMD efficiency is a common phenomenon in human populations and that an individual’s NMD efficiency should be taken into consideration when testing, developing, and making therapeutic decisions for diseases caused by genes harboring PTCs. PMID:24239855

ANALYSIS OF BIOTIC AND ABIOTIC FACTORS INFLUENCING THE OCCURRENCE OF WEST NILE VIRUS INFECTION IN TUNISIA.

PubMed

Ben Hassine, Th; Calistri, P; Ippoliti, C; Conte, A; Danzetta, M L; Bruno, R; Lelli, R; Bejaoui, M; Hammami, S

2014-01-01

Eco-climatic conditions are often associated with the occurrence of West Nile Disease (WND) cases. Among the complex set of biotic and abiotic factors influencing the emergence and spread of this vector-borne disease, two main variables have been considered to have a great influence on the probability of West Nile Virus (WNV) introduction and circulation in Tunisia: the presence of susceptible bird populations and the existence of geographical areas where the environmental and climatic conditions are more favourable to mosquito multiplications. The aim of this study was to identify and classify the climatic and environmental variables possibly associated with the occurrence of WNVhuman cases in Tunisia. The following environmental and climatic variables have been considered: wetlands and humid areas, Normalised Difference Vegetation Index (NDVI), temperatures and elevation. A preliminary analysis for the characterization of main variables associated with areas with a history of WNV human cases in Tunisia between 1997 and 2011 has been made. This preliminary analysis clearly indicates the closeness to marshes ecosystem, where migratory bird populations are located, as an important risk factor for WNV infection. On the contrary the temperature absolute seems to be not a significant factor in Tunisian epidemiological situation. In relation to NDVI values, more complex considerations should be made.

Avionics Integrity Program (AVIP). Volume 4. Force Management - Economic Life Considerations.

DTIC Science & Technology

1984-03-01

often used to refer to the period of time during which financial considerations justify the continued use of an existing system. The study addresses...rejporLs incl-ude contractor ei forts between September 1983 and Marih 1984. Each report represents a completed study in a specific area and stands alone...during which financial considerations justify the selection or continued use of a system. A variety of definitions currently exist for economic life. One

Characteristics and Proximal Outcomes of Calls Made to Suicide Crisis Hotlines in California.

PubMed

Ramchand, Rajeev; Jaycox, Lisa; Ebener, Pat; Gilbert, Mary Lou; Barnes-Proby, Dionne; Goutam, Prodyumna

2017-01-01

Suicide hotlines are commonly used to prevent suicides, although centers vary with respect to their management and operations. To describe variability across suicide prevention hotlines. Live monitoring of 241 calls was conducted at 10 suicide prevention hotlines in California. Call centers are similar with respect to caller characteristics and the concerns callers raise during their calls. The proportion of callers at risk for suicide varied from 3 to 57%. Compliance with asking about current suicide risk, past ideation, and past attempts also ranged considerably. Callers to centers that were part of the National Suicide Prevention Lifeline (NSPL) were more likely to experience reduced distress than callers to centers that were not part of the NSPL. Because callers do not generally choose the center or responder that will take their call, it is critical to promote quality across call centers and minimize the variability that currently exists. Accrediting bodies, funders, and crisis centers should require that centers continuously monitor calls to ensure and improve call quality.

Curricular Approaches in Research Ethics Education: Reflecting on More and Less Effective Practices in Instructional Content.

PubMed

Torrence, Brett S; Watts, Logan L; Mulhearn, Tyler J; Turner, Megan R; Todd, E Michelle; Mumford, Michael D; Connelly, Shane

2017-01-01

Over the past decade, the effectiveness of ethics education programs has increased with regard to trainee outcomes, such as knowledge, awareness, and ethical decision making. However, despite the overall improvement in training effectiveness, considerable variability still exists across programs. One potential source of variability arises from the substantial range in instructional training content utilized across ethics training courses. The goal of the present effort was to clarify which approaches in ethics education result in positive training outcomes through the identification of instructional content themes. Through a qualitative review of ethics training courses, we identified key themes in instructional content curriculum associated with effective courses: domain-general, domain-specific, standard compliance, professionalism, and process-based. In addition, we identified key themes associated with less effective courses: mixed-specificity, narrow coverage, and idealized ethics. Descriptions and key characteristics of each theme along with example courses are provided. Implications of the content themes for ethics education are discussed.

Shape Optimization of Supersonic Turbines Using Response Surface and Neural Network Methods

NASA Technical Reports Server (NTRS)

Papila, Nilay; Shyy, Wei; Griffin, Lisa W.; Dorney, Daniel J.

2001-01-01

Turbine performance directly affects engine specific impulse, thrust-to-weight ratio, and cost in a rocket propulsion system. A global optimization framework combining the radial basis neural network (RBNN) and the polynomial-based response surface method (RSM) is constructed for shape optimization of a supersonic turbine. Based on the optimized preliminary design, shape optimization is performed for the first vane and blade of a 2-stage supersonic turbine, involving O(10) design variables. The design of experiment approach is adopted to reduce the data size needed by the optimization task. It is demonstrated that a major merit of the global optimization approach is that it enables one to adaptively revise the design space to perform multiple optimization cycles. This benefit is realized when an optimal design approaches the boundary of a pre-defined design space. Furthermore, by inspecting the influence of each design variable, one can also gain insight into the existence of multiple design choices and select the optimum design based on other factors such as stress and materials considerations.

High sequence variability among hemocyte-specific Kazal-type proteinase inhibitors in decapod crustaceans.

PubMed

Cerenius, Lage; Liu, Haipeng; Zhang, Yanjiao; Rimphanitchayakit, Vichien; Tassanakajon, Anchalee; Gunnar Andersson, M; Söderhäll, Kenneth; Söderhäll, Irene

2010-01-01

Crustacean hemocytes were found to produce a large number of transcripts coding for Kazal-type proteinase inhibitors (KPIs). A detailed study performed with the crayfish Pacifastacus leniusculus and the shrimp Penaeus monodon revealed the presence of at least 26 and 20 different Kazal domains from the hemocyte KPIs, respectively. Comparisons with KPIs from other taxa indicate that the sequences of these domains evolve rapidly. A few conserved positions, e.g. six invariant cysteines were present in all domain sequences whereas the position of P1 amino acid, a determinant for substrate specificity, varied highly. A study with a single crayfish animal suggested that even at the individual level considerable sequence variability among hemocyte KPIs produced exist. Expression analysis of four crayfish KPI transcripts in hematopoietic tissue cells and different hemocyte types suggest that some of these KPIs are likely to be involved in hematopoiesis or hemocyte release as they were produced in particular hemocyte types or maturation stages only.

Exploring the Climate Change, Migration and Conflict Nexus.

PubMed

Burrows, Kate; Kinney, Patrick L

2016-04-22

The potential link between climate change, migration, and conflict has been widely discussed and is increasingly viewed by policy makers as a security issue. However, considerable uncertainty remains regarding the role that climate variability and change play among the many drivers of migration and conflict. The overall objective of this paper is to explore the potential pathways linking climate change, migration and increased risk of conflict. We review the existing literature surrounding this issue and break the problem into two components: the links between climate change and migration, and those between migration and conflict. We found a large range of views regarding the importance of climate change as a driver for increasing rates of migration and subsequently of conflict. We argue that future research should focus not only on the climate-migration-conflict pathway but also work to understand the other pathways by which climate variability and change might exacerbate conflict. We conclude by proposing five questions to help guide future research on the link between climate change, migration, and conflict.

Exploring the Climate Change, Migration and Conflict Nexus

PubMed Central

Burrows, Kate; Kinney, Patrick L.

2016-01-01

The potential link between climate change, migration, and conflict has been widely discussed and is increasingly viewed by policy makers as a security issue. However, considerable uncertainty remains regarding the role that climate variability and change play among the many drivers of migration and conflict. The overall objective of this paper is to explore the potential pathways linking climate change, migration and increased risk of conflict. We review the existing literature surrounding this issue and break the problem into two components: the links between climate change and migration, and those between migration and conflict. We found a large range of views regarding the importance of climate change as a driver for increasing rates of migration and subsequently of conflict. We argue that future research should focus not only on the climate-migration-conflict pathway but also work to understand the other pathways by which climate variability and change might exacerbate conflict. We conclude by proposing five questions to help guide future research on the link between climate change, migration, and conflict. PMID:27110806

Open string with a background B field as the first order mechanics, noncommutativity, and soldering formalism

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

Deriglazov, A. A.; Neves, C.; Oliveira, W.

2007-09-15

To study noncommutativity properties of the open string with constant B field, we construct a mechanical action that reproduces classical dynamics of the string sector under consideration. It allows one to apply the Dirac quantization procedure for constrained systems in a direct and unambiguous way. The mechanical action turns out to be the first order system without taking the strong field limit B{yields}{infinity}. In particular, it is true for the zero mode of the string coordinate, which means that the noncommutativity is an intrinsic property of this mechanical system. We describe the arbitrariness in the relation existing between the mechanicalmore » and the string variables and show that noncommutativity of the string variables on the boundary can be removed. This is in correspondence with the result of Seiberg and Witten on the relation among noncommutative and ordinary Yang-Mills theories. The recently developed soldering formalism helps us to establish a connection between the original open string action and the Polyakov action.« less

[Variations among Spanish regions in the use of three cardiovascular technologies].

PubMed

Fitch-Warner, Kathryn; García de Yébenes, María J; Lázaro y de Mercado, Pablo; Belaza-Santurde, Javier

2006-12-01

There is evidence that some geographic variations in the use of medical technologies are not explained by differences in disease burden. The objectives of this study were to quantify variability in the use of percutaneous coronary intervention (PCI), implantable cardioverter-defibrillators (ICDs), and cardiac resynchronization therapy (CRT) in Spanish autonomous regions and to try to explain the variability found for the first two technologies. Linear regression models were developed in which the number of procedures performed per million population (pmp) in 2003 in each autonomous region was the dependent variable. Independent variables used included indices of technology provision, regional wealth, and disease burden. For PCI, the mean utilization rate for the whole of Spain was 1038 procedures pmp, with a high-low ratio of 1.95. Differences in gross domestic product explained 21% of the variability, but there was no relationship between the number of procedures performed and disease burden. For ICDs, the mean number of procedures performed in the whole of Spain was 46 pmp, with a high-low ratio of 3.04. As for PCI, differences in regional wealth explained 40% of the variability, with disease burden making no contribution. For CRT, the mean number of procedures performed in Spain in 2003 was 15 pmp, with a high-low ratio of 15.7. The considerable regional variation that exists in the use of these three medical technologies is principally explained by differences in regional wealth and not in disease burden.

Convex Formulations of Learning from Crowds

NASA Astrophysics Data System (ADS)

Kajino, Hiroshi; Kashima, Hisashi

It has attracted considerable attention to use crowdsourcing services to collect a large amount of labeled data for machine learning, since crowdsourcing services allow one to ask the general public to label data at very low cost through the Internet. The use of crowdsourcing has introduced a new challenge in machine learning, that is, coping with low quality of crowd-generated data. There have been many recent attempts to address the quality problem of multiple labelers, however, there are two serious drawbacks in the existing approaches, that are, (i) non-convexity and (ii) task homogeneity. Most of the existing methods consider true labels as latent variables, which results in non-convex optimization problems. Also, the existing models assume only single homogeneous tasks, while in realistic situations, clients can offer multiple tasks to crowds and crowd workers can work on different tasks in parallel. In this paper, we propose a convex optimization formulation of learning from crowds by introducing personal models of individual crowds without estimating true labels. We further extend the proposed model to multi-task learning based on the resemblance between the proposed formulation and that for an existing multi-task learning model. We also devise efficient iterative methods for solving the convex optimization problems by exploiting conditional independence structures in multiple classifiers.

Community models for wildlife impact assessment: a review of concepts and approaches

USGS Publications Warehouse

Schroeder, Richard L.

1987-01-01

The first two sections of this paper are concerned with defining and bounding communities, and describing those attributes of the community that are quantifiable and suitable for wildlife impact assessment purposes. Prior to the development or use of a community model, it is important to have a clear understanding of the concept of a community and a knowledge of the types of community attributes that can serve as outputs for the development of models. Clearly defined, unambiguous model outputs are essential for three reasons: (1) to ensure that the measured community attributes relate to the wildlife resource objectives of the study; (2) to allow testing of the outputs in experimental studies, to determine accuracy, and to allow for improvements based on such testing; and (3) to enable others to clearly understand the community attribute that has been measured. The third section of this paper described input variables that may be used to predict various community attributes. These input variables do not include direct measures of wildlife populations. Most impact assessments involve projects that result in drastic changes in habitat, such as changes in land use, vegetation, or available area. Therefore, the model input variables described in this section deal primarily with habitat related features. Several existing community models are described in the fourth section of this paper. A general description of each model is provided, including the nature of the input variables and the model output. The logic and assumptions of each model are discussed, along with data requirements needed to use the model. The fifth section provides guidance on the selection and development of community models. Identification of the community attribute that is of concern will determine the type of model most suitable for a particular application. This section provides guidelines on selected an existing model, as well as a discussion of the major steps to be followed in modifying an existing model or developing a new model. Considerations associated with the use of community models with the Habitat Evaluation Procedures are also discussed. The final section of the paper summarizes major findings of interest to field biologists and provides recommendations concerning the implementation of selected concepts in wildlife community analyses.

Assessing adaptation to the health risks of climate change: what guidance can existing frameworks provide?

PubMed

Füssel, Hans-Martin

2008-02-01

Climate change adaptation assessments aim at assisting policy-makers in reducing the health risks associated with climate change and variability. This paper identifies key characteristics of the climate-health relationship and of the adaptation decision problem that require consideration in climate change adaptation assessments. It then analyzes whether these characteristics are appropriately considered in existing guidelines for climate impact and adaptation assessment and in pertinent conceptual models from environmental epidemiology. The review finds three assessment guidelines based on a generalized risk management framework to be most useful for guiding adaptation assessments of human health. Since none of them adequately addresses all key challenges of the adaptation decision problem, actual adaptation assessments need to combine elements from different guidelines. Established conceptual models from environmental epidemiology are found to be of limited relevance for assessing and planning adaptation to climate change since the prevailing toxicological model of environmental health is not applicable to many climate-sensitive health risks.

Assessing the Queuing Process Using Data Envelopment Analysis: an Application in Health Centres.

PubMed

Safdar, Komal A; Emrouznejad, Ali; Dey, Prasanta K

2016-01-01

Queuing is one of the very important criteria for assessing the performance and efficiency of any service industry, including healthcare. Data Envelopment Analysis (DEA) is one of the most widely-used techniques for performance measurement in healthcare. However, no queue management application has been reported in the health-related DEA literature. Most of the studies regarding patient flow systems had the objective of improving an already existing Appointment System. The current study presents a novel application of DEA for assessing the queuing process at an Outpatients' department of a large public hospital in a developing country where appointment systems do not exist. The main aim of the current study is to demonstrate the usefulness of DEA modelling in the evaluation of a queue system. The patient flow pathway considered for this study consists of two stages; consultation with a doctor and pharmacy. The DEA results indicated that waiting times and other related queuing variables included need considerable minimisation at both stages.

Breeding blueberries for a changing global environment: a review

PubMed Central

Lobos, Gustavo A.; Hancock, James F.

2015-01-01

Today, blueberries are recognized worldwide as one of the foremost health foods, becoming one of the crops with the highest productive and commercial projections. Over the last 100 years, the geographical area where highbush blueberries are grown has extended dramatically into hotter and drier environments. The expansion of highbush blueberry growing into warmer regions will be challenged in the future by increases in average global temperature and extreme fluctuations in temperature and rainfall patterns. Considerable genetic variability exists within the blueberry gene pool that breeders can use to meet these challenges, but traditional selection techniques can be slow and inefficient and the precise adaptations of genotypes often remain hidden. Marker assisted breeding (MAB) and phenomics could aid greatly in identifying those individuals carrying adventitious traits, increasing selection efficiency and shortening the rate of cultivar release. While phenomics have begun to be used in the breeding of grain crops in the last 10 years, their use in fruit breeding programs it is almost non-existent. PMID:26483803

Thriving on Pressure: A Factor Mixture Analysis of Sport Performers' Responses to Competitive Encounters.

PubMed

Brown, Daniel J; Arnold, Rachel; Standage, Martyn; Fletcher, David

2017-12-01

Although considerable research exists on performers' responses to sporting encounters, little is known about thriving in sport contexts. The current study examined if distinct response patterns existed between sport performers who thrived in competitive encounters compared with those who did not. Participants were 535 sport performers (134 women; M age  = 23.60 years, SD age  = 8.08; M competing  = 11.84 years, SD competing  = 7.11). Results of factor mixture analysis supported a four-profile solution comprising a thriving group (n = 146), a low-functioning group (n = 38), and two groups characterized by scores marginally above (n = 131) and below (n = 209) the sample mean. Profile membership was found to be predicted by personal enablers (viz., personal resilient qualities, psychological skills use) and process variables (viz., basic psychological need satisfaction and frustration, challenge appraisal). This examination of thriving in sport performers offers significant implications for research and practice.

High sensitivity capacitive MEMS microphone with spring supported diaphragm

NASA Astrophysics Data System (ADS)

Mohamad, Norizan; Iovenitti, Pio; Vinay, Thurai

2007-12-01

Capacitive microphones (condenser microphones) work on a principle of variable capacitance and voltage by the movement of its electrically charged diaphragm and back plate in response to sound pressure. There has been considerable research carried out to increase the sensing performance of microphones while reducing their size to cater for various modern applications such as mobile communication and hearing aid devices. This paper reviews the development and current performance of several condenser MEMS microphone designs, and introduces a microphone with spring supported diaphragm to further improve condenser microphone performance. The numerical analysis using Coventor FEM software shows that this new microphone design has a higher mechanical sensitivity compared to the existing edge clamped flat diaphragm condenser MEMS microphone. The spring supported diaphragm is shown to have a flat frequency response up to 7 kHz and more stable under the variations of the diaphragm residual stress. The microphone is designed to be easily fabricated using the existing silicon fabrication technology and the stability against the residual stress increases its reproducibility.

Design and energetic evaluation of a prosthetic knee joint actuator with a lockable parallel spring.

PubMed

Geeroms, J; Flynn, L; Jimenez-Fabian, R; Vanderborght, B; Lefeber, D

2017-02-03

There are disadvantages to existing damping knee prostheses which cause an asymmetric gait and higher metabolic cost during level walking compared to non-amputees. Most existing active knee prostheses which could benefit the amputees use a significant amount of energy and require a considerable motor. In this work, a novel semi-active actuator with a lockable parallel spring for a prosthetic knee joint has been developed and tested. This actuator is able to provide an approximation of the behavior of a healthy knee during most of the gait cycle of level walking. This actuator is expanded with a series-elastic actuator to mimic the full gait cycle and enable its use in other functional tasks like stair climbing and sit-to-stance. The proposed novel actuator reduces the energy consumption for the same trajectory with respect to a compliant or directly-driven prosthetic active knee joint and improves the approximation of healthy knee behavior during level walking compared to passive or variable damping knee prostheses.

Independent data monitoring committees: Preparing a path for the future

PubMed Central

Hess, Connie N.; Roe, Matthew T.; Gibson, C. Michael; Temple, Robert J.; Pencina, Michael J.; Zarin, Deborah A.; Anstrom, Kevin J.; Alexander, John H.; Sherman, Rachel E.; Fiedorek, Fred T.; Mahaffey, Kenneth W.; Lee, Kerry L.; Chow, Shein-Chung; Armstrong, Paul W.; Califf, Robert M.

2014-01-01

Independent data monitoring committees (IDMCs) were introduced to monitor patient safety and study conduct in randomized clinical trials (RCTs), but certain challenges regarding the utilization of IDMCs have developed. First, the roles and responsibilities of IDMCs are expanding, perhaps due to increasing trial complexity and heterogeneity regarding medical, ethical, legal, regulatory, and financial issues. Second, no standard for IDMC operating procedures exists, and there is uncertainty about who should determine standards and whether standards should vary with trial size and design. Third, considerable variability in communication pathways exist across IDMC interfaces with regulatory agencies, academic coordinating centers, and sponsors. Finally, there has been a substantial increase in the number of RCTs using IDMCs, yet there is no set of qualifications to help guide the training and development of the next generation of IDMC members. Recently, an expert panel of representatives from government, industry, and academia assembled at the Duke Clinical Research Institute to address these challenges and to develop recommendations for the future utilization of IDMCs in RCTs. PMID:25066551

Belief and disbelief in the existence of genetic risk factors for suicide: cross-cultural comparisons.

PubMed

Voracek, Martin

2007-12-01

There is evidence for widespread disbelief in the genetics of suicide, despite recent research progress in this area and convergent evidence supporting a role for genetic factors. This study analyzed the beliefs held in 8 samples (total N = 1224) of various types (psychology, medical, and various undergraduates, psychology graduates, and the general population) from 6 countries located on 3 continents (Austria, Canada, Malaysia, Romania, United Kingdom, and the USA). Endorsement rates for the existence of genetic risk factors for suicide ranged from 26% and 30% (Austrian psychology undergraduates and general population) to around 50% (psychology undergraduates in the USA and United Kingdom). In the 8 samples, respondents' sex, age, religiosity, political orientation, and other demographic variables were, for the most part, unrelated, but overall knowledge about suicide throughout was related positively to endorsement rates. Consistent with previous research, across a considerable variety of sample types and cultural settings there was no evidence for a clear majority believing in genetic bases for suicide.

Capacity Payments in Restructured Markets under Low and High Penetration Levels of Renewable Energy

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

Jenkin, Thomas; Beiter, Philipp; Margolis, Robert

There is considerable debate about the degree to which restructured markets perform successfully in their use of capacity markets. In providing appropriate incentives for new and existing generation to meet reliability requirements, a variety of capacity market designs have developed across RTOs and ISOs in the United States and internationally. Growing levels of variable renewable energy (VRE) resources arguably create new challenges for capacity market designs, because VREs suppress energy prices while providing relatively little capacity, with these effects increase with VRE penetration. The purpose of this report is threefold. First, we provide a brief outline of the purpose andmore » design of various capacity markets under consideration using variable resource requirement (VRR) demand curves. Second, we discuss some of the main challenges raised in existing literature and a set of interviews that we conducted with market participants, regulators, and observers, including where there substantive differences in opinion. Third, we consider some of the challenges that may be specific to higher penetration levels of VRE. While the well known 'merit order' effect from VRE can be expected to suppress wholesale energy prices and revenue, this may be partly mitigated by increased capacity payments and the greater importance of AS payments for flexible capacity. The potential for greater reliance on capacity markets for generator revenues may amplify any inefficiency and costs associated with capacity price volatility and other suboptimal market design choices. Regulatory intervention to ensure adequate capacity payments and ancillary service revenue may become more prevalent under current market designs as the timescale for market signals shifts increasingly from near term (e.g., day-ahead in wholesale electricity markets) to longer term (annual intervals in capacity markets). Our review and discussion with market participants suggest substantive challenges may remain in implementing capacity markets that provide both adequate operational and investment incentives, particularly under high-VRE scenarios with greater need for flexible capacity.« less

The future of hydropower planning modeling

NASA Astrophysics Data System (ADS)

Haas, J.; Zuñiga, D.; Nowak, W.; Olivares, M. A.; Castelletti, A.; Thilmant, A.

2017-12-01

Planning the investment and operation of hydropower plants with optimization tools dates back to the 1970s. The focus used to be solely on the provision of energy. However, advances in computational capacity and solving algorithms, dynamic markets, expansion of renewable sources, and a better understanding of hydropower environmental impacts have recently led to the development of novel planning approaches. In this work, we provide a review, systematization, and trend analysis of these approaches. Further, through interviews with experts, we outline the future of hydropower planning modeling and identify the gaps towards it. We classified the found models along environmental, economic, multipurpose and technical criteria. Environmental interactions include hydropeaking mitigation, water quality protection and limiting greenhouse gas emissions from reservoirs. Economic and regulatory criteria consider uncertainties of fossil fuel prices and relicensing of water rights and power purchase agreements. Multipurpose considerations account for irrigation, tourism, flood protection and drinking water. Recently included technical details account for sedimentation in reservoirs and variable efficiencies of turbines. Additional operational considerations relate to hydrological aspects such as dynamic reservoir inflows, water losses, and climate change. Although many of the above criteria have been addressed in detail on a project-to-project basis, models remain overly simplistic for planning large power fleets. Future hydropower planning tools are expected to improve the representation of the water-energy nexus, including environmental and multipurpose criteria. Further, they will concentrate on identifying new sources of operational flexibility (e.g. through installing additional turbines and pumps) for integrating renewable energy. The operational detail will increase, potentially emphasizing variable efficiencies, storage capacity losses due to sedimentation, and the timing of inflows (which are becoming more variable under climate change). Finally, the relicensing of existing operations and planning new installations are subject to deep uncertainties that need to be captured.

A new multi-sensor integrated index for drought monitoring

NASA Astrophysics Data System (ADS)

Jiao, W.; Wang, L.; Tian, C.

2017-12-01

Drought is perceived as one of the most expensive and least understood natural disasters. The remote-sensing-based integrated drought indices, which integrate multiple variables, could reflect the drought conditions more comprehensively than single drought indices. However, most of current remote-sensing-based integrated drought indices focus on agricultural drought (i.e., deficit in soil moisture), their application in monitoring meteorological drought (i.e., deficit in precipitation) was limited. More importantly, most of the remote-sensing-based integrated drought indices did not take into consideration of the spatially non-stationary nature of the related variables, so such indices may lose essential local details when integrating multiple variables. In this regard, we proposed a new mathematical framework for generating integrated drought index for meteorological drought monitoring. The geographically weighted regression (GWR) model and principal component analysis were used to composite Moderate-resolution Imaging Spectroradiometer (MODIS) based temperature condition index (TCI), the Vegetation Index based on the Universal Pattern Decomposition method (VIUPD) based vegetation condition index (VCI), tropical rainfall measuring mission (TRMM) based Precipitation Condition Index (PCI) and Advanced Microwave Scanning Radiometer-EOS (AMSR-E) based soil moisture condition index (SMCI). We called the new remote-sensing-based integrated drought index geographical-location-based integrated drought index (GLIDI). We examined the utility of the GLIDI for drought monitoring in various climate divisions across the continental United States (CONUS). GLIDI showed high correlations with in-situ drought indices and outperformed most other existing drought indices. The results also indicate that the performance of GLIDI is not affected by environmental factors such as land cover, precipitation, temperature and soil conditions. As such, the GLIDI has considerable potential for drought monitoring across various environmental conditions.

Environmental Assessment. Moanalua Shopping Center Redevelopment Oahu, Hawaii

DTIC Science & Technology

2004-08-01

redevelop the approximately 15-acre MSC site as in-kind consideration for the fair market rent which would be due under a 40-year lease of the...the existing approximately 15-acre (6-hectare) MSC site as in-kind consideration for the fair market rent which would be due under a 40-year lease of...would redevelop the existing MSC site as in-kind consideration for the fair market rent which would be due under a 40-year lease of the properties

Does intrinsic light heterogeneity in Ricinus communis L. monospecific thickets drive species' population dynamics?

PubMed

Goyal, Neha; Shah, Kanhaiya; Sharma, Gyan Prakash

2018-06-19

Ricinus communis L. colonizes heterogeneous urban landscapes as monospecific thickets. The ecological understanding on colonization success of R. communis population due to variable light availability is lacking. Therefore, to understand the effect of intrinsic light heterogeneity on species' population dynamics, R. communis populations exposed to variable light availability (low, intermediate, and high) were examined for performance strategies through estimation of key vegetative, eco-physiological, biochemical, and reproductive traits. Considerable variability existed in studied plant traits in response to available light. Individuals inhabiting high-light conditions exhibited high eco-physiological efficiency and reproductive performance that potentially confers population boom. Individuals exposed to low light showed poor performance in terms of eco-physiology and reproduction, which attribute to bust. However, individuals in intermediate light were observed to be indeterminate to light availability, potentially undergoing trait modulations with uncertainty of available light. Heterogeneous light availability potentially drives the boom and bust cycles in R. communis monospecific thickets. Such boom and bust cycles subsequently affect species' dominance, persistence, collapse, and/or resurgence as an aggressive colonizer in contrasting urban environments. The study fosters extensive monitoring of R. communis thickets to probe underlying mechanism(s) affecting expansions and/or collapses of colonizing populations.

System reliability analysis of granular filter for protection against piping in dams

NASA Astrophysics Data System (ADS)

Srivastava, A.; Sivakumar Babu, G. L.

2015-09-01

Granular filters are provided for the safety of water retaining structure for protection against piping failure. The phenomenon of piping triggers when the base soil to be protected starts migrating in the direction of seepage flow under the influence of seepage force. To protect base soil from migration, the voids in the filter media should be small enough but it should not also be too small to block smooth passage of seeping water. Fulfilling these two contradictory design requirements at the same time is a major concern for the successful performance of granular filter media. Since Terzaghi era, conventionally, particle size distribution (PSD) of granular filters is designed based on particle size distribution characteristics of the base soil to be protected. The design approach provides a range of D15f value in which the PSD of granular filter media should fall and there exist infinite possibilities. Further, safety against the two critical design requirements cannot be ensured. Although used successfully for many decades, the existing filter design guidelines are purely empirical in nature accompanied with experience and good engineering judgment. In the present study, analytical solutions for obtaining the factor of safety with respect to base soil particle migration and soil permeability consideration as proposed by the authors are first discussed. The solution takes into consideration the basic geotechnical properties of base soil and filter media as well as existing hydraulic conditions and provides a comprehensive solution to the granular filter design with ability to assess the stability in terms of factor of safety. Considering the fact that geotechnical properties are variable in nature, probabilistic analysis is further suggested to evaluate the system reliability of the filter media that may help in risk assessment and risk management for decision making.

The role of impulse parameters in force variability

NASA Technical Reports Server (NTRS)

Carlton, L. G.; Newell, K. M.

1986-01-01

One of the principle limitations of the human motor system is the ability to produce consistent motor responses. When asked to repeatedly make the same movement, performance outcomes are characterized by a considerable amount of variability. This occurs whether variability is expressed in terms of kinetics or kinematics. Variability in performance is of considerable importance because for tasks requiring accuracy it is a critical variable in determining the skill of the performer. What has long been sought is a description of the parameter or parameters that determine the degree of variability. Two general experimental protocals were used. One protocal is to use dynamic actions and record variability in kinematic parameters such as spatial or temporal error. A second strategy was to use isometric actions and record kinetic variables such as peak force produced. What might be the important force related factors affecting variability is examined and an experimental approach to examine the influence of each of these variables is provided.

Reconciling Environmental and Flood Control Goals on an Arid-Zone River: Case Study of the Limitrophe Region of the Lower Colorado River in the United States and Mexico

NASA Astrophysics Data System (ADS)

Glenn, Edward P.; Hucklebridge, Kate; Hinojosa-Huerta, Osvel; Nagler, Pamela L.; Pitt, Jennifer

2008-03-01

Arid zone rivers have highly variable flow rates, and flood control projects are needed to protect adjacent property from flood damage. On the other hand, riparian corridors provide important wildlife habitat, especially for birds, and riparian vegetation is adapted to the natural variability in flows on these rivers. While environmental and flood control goals might appear to be at odds, we show that both goals can be accommodated in the Limitrophe Region (the shared border between the United States and Mexico) on the Lower Colorado River. In 1999, the International Boundary and Water Commission proposed a routine maintenance project to clear vegetation and create a pilot channel within the Limitrophe Region to improve flow capacity and delineate the border. In 2000, however, Minute 306 to the international water treaty was adopted, which calls for consideration of environmental effects of IBWC actions. We conducted vegetation and bird surveys within the Limitrophe and found that this river segment is unusually rich in native cottonwood and willow trees, marsh habitat, and resident and migratory birds compared to flow-regulated segments of river. A flood-frequency analysis showed that the existing levee system can easily contain a 100 year flood even if vegetation is not removed, and the existing braided channel system has greater carrying capacity than the proposed pilot channel.

Systematic review of tonsil surgery quality registers and introduction of the Nordic Tonsil Surgery Register Collaboration.

PubMed

Ruohoalho, Johanna; Østvoll, Eirik; Bratt, Mette; Bugten, Vegard; Bäck, Leif; Mäkitie, Antti; Ovesen, Therese; Stalfors, Joacim

2018-06-01

Surgical quality registers provide tools to measure and improve the outcome of surgery. International register collaboration creates an opportunity to assess and critically evaluate national practices, and increases the size of available datasets. Even though millions of yearly tonsillectomies and tonsillotomies are performed worldwide, clinical practices are variable and inconsistency of evidence regarding the best clinical practice exists. The need for quality improvement actions is evident. We aimed to systematically investigate the existing tonsil surgery quality registers found in the literature, and to provide a thorough presentation of the planned Nordic Tonsil Surgery Register Collaboration. A systematic literature search of MEDLINE and EMBASE databases (from January 1990 to December 2016) was conducted to identify registers, databases, quality improvement programs or comprehensive audit programs addressing tonsil surgery. We identified two active registers and three completed audit programs focusing on tonsil surgery quality registration. Recorded variables were fairly similar, but considerable variation in coverage, number of operations included and length of time period for inclusion was discovered. Considering tonsillectomies and tonsillotomies being among the most commonly performed surgical procedures in otorhinolaryngology, it is surprising that only two active registers could be identified. We present a Nordic Tonsil Surgery Register Collaboration-an international tonsil surgery quality register project aiming to provide accurate benchmarks and enhance the quality of tonsil surgery in Denmark, Finland, Norway and Sweden.

Reconciling environmental and flood control goals on an arid-zone river: case study of the limitrophe region of the lower colorado river in the United States and Mexico.

PubMed

Glenn, Edward P; Hucklebridge, Kate; Hinojosa-Huerta, Osvel; Nagler, Pamela L; Pitt, Jennifer

2008-03-01

Arid zone rivers have highly variable flow rates, and flood control projects are needed to protect adjacent property from flood damage. On the other hand, riparian corridors provide important wildlife habitat, especially for birds, and riparian vegetation is adapted to the natural variability in flows on these rivers. While environmental and flood control goals might appear to be at odds, we show that both goals can be accommodated in the Limitrophe Region (the shared border between the United States and Mexico) on the Lower Colorado River. In 1999, the International Boundary and Water Commission proposed a routine maintenance project to clear vegetation and create a pilot channel within the Limitrophe Region to improve flow capacity and delineate the border. In 2000, however, Minute 306 to the international water treaty was adopted, which calls for consideration of environmental effects of IBWC actions. We conducted vegetation and bird surveys within the Limitrophe and found that this river segment is unusually rich in native cottonwood and willow trees, marsh habitat, and resident and migratory birds compared to flow-regulated segments of river. A flood-frequency analysis showed that the existing levee system can easily contain a 100 year flood even if vegetation is not removed, and the existing braided channel system has greater carrying capacity than the proposed pilot channel.

Higher order approximation to the Hill problem dynamics about the libration points

NASA Astrophysics Data System (ADS)

Lara, Martin; Pérez, Iván L.; López, Rosario

2018-06-01

An analytical solution to the Hill problem Hamiltonian expanded about the libration points has been obtained by means of perturbation techniques. In order to compute the higher orders of the perturbation solution that are needed to capture all the relevant periodic orbits originated from the libration points within a reasonable accuracy, the normalization is approached in complex variables. The validity of the solution extends to energy values considerably far away from that of the libration points and, therefore, can be used in the computation of Halo orbits as an alternative to the classical Lindstedt-Poincaré approach. Furthermore, the theory correctly predicts the existence of the two-lane bridge of periodic orbits linking the families of planar and vertical Lyapunov orbits.

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

Garten, Lauren M.; Zakutayev, Andriy; Perkins, John D.

Beta-gallium oxide (β-Ga 2O 3) is of increasing interest to the optoelectronic community for transparent conductor and power electronic applications. Considerable variability exists in the literature on the growth and doping of Ga 2O 3 films, especially as a function of growth approach, temperature, and oxygen partial pressure. Here pulsed laser deposition (PLD) was used to grow high-quality β-Ga 2O 3 films on (0001) sapphire and (–201) Ga 2O 3 single crystals and to explore the growth, stability, and dopability of these films as function of temperature and oxygen partial pressure. As a result, there is a strong temperature dependencemore » to the phase formation, morphology, and electronic properties of β-Ga 2O 3 from 350 to 550 °C.« less

Future Translational Applications From the Contemporary Genomics Era

PubMed Central

Fox, Caroline S.; Hall, Jennifer L.; Arnett, Donna K.; Ashley, Euan A.; Delles, Christian; Engler, Mary B.; Freeman, Mason W.; Johnson, Julie A.; Lanfear, David E.; Liggett, Stephen B.; Lusis, Aldons J.; Loscalzo, Joseph; MacRae, Calum A.; Musunuru, Kiran; Newby, L. Kristin; O’Donnell, Christopher J.; Rich, Stephen S.; Terzic, Andre

2016-01-01

The field of genetics and genomics has advanced considerably with the achievement of recent milestones encompassing the identification of many loci for cardiovascular disease and variable drug responses. Despite this achievement, a gap exists in the understanding and advancement to meaningful translation that directly affects disease prevention and clinical care. The purpose of this scientific statement is to address the gap between genetic discoveries and their practical application to cardiovascular clinical care. In brief, this scientific statement assesses the current timeline for effective translation of basic discoveries to clinical advances, highlighting past successes. Current discoveries in the area of genetics and genomics are covered next, followed by future expectations, tools, and competencies for achieving the goal of improving clinical care. PMID:25882488

Mimetic Theory and Scapegoating in the Age of Cyberbullying: The Case of Phoebe Prince

ERIC Educational Resources Information Center

Norman, James O'Higgins; Connolly, Justin

2011-01-01

Whilst traditional forms of bullying have and continue to receive considerable attention in the literature, research on technology-enabled bullying remains in an embryonic stage and considerable deficits exist in our understanding of the nature, extent, dynamics and consequents of this new form of bullying. Of the limited studies that exist on…

The Role of Trait Emotional Intelligence in Academic Performance: Theoretical Overview and Empirical Update.

PubMed

Perera, Harsha N

2016-01-01

Considerable debate still exists among scholars over the role of trait emotional intelligence (TEI) in academic performance. The dominant theoretical position is that TEI should be orthogonal or only weakly related to achievement; yet, there are strong theoretical reasons to believe that TEI plays a key role in performance. The purpose of the current article is to provide (a) an overview of the possible theoretical mechanisms linking TEI with achievement and (b) an update on empirical research examining this relationship. To elucidate these theoretical mechanisms, the overview draws on multiple theories of emotion and regulation, including TEI theory, social-functional accounts of emotion, and expectancy-value and psychobiological model of emotion and regulation. Although these theoretical accounts variously emphasize different variables as focal constructs, when taken together, they provide a comprehensive picture of the possible mechanisms linking TEI with achievement. In this regard, the article redresses the problem of vaguely specified theoretical links currently hampering progress in the field. The article closes with a consideration of directions for future research.

Resilience, rapid transitions and regime shifts: fingerprinting the responses of Lake Żabińskie (NE Poland) to climate variability and human disturbance since 1000 AD

NASA Astrophysics Data System (ADS)

Tylmann, Wojciech; Hernández-Almeida, Iván; Grosjean, Martin; José Gómez Navarro, Juan; Larocque-Tobler, Isabelle; Bonk, Alicja; Enters, Dirk; Ustrzycka, Alicja; Piotrowska, Natalia; Przybylak, Rajmund; Wacnik, Agnieszka; Witak, Małgorzata

2016-04-01

Rapid ecosystem transitions and adverse effects on ecosystem services as responses to combined climate and human impacts are of major concern. Yet few quantitative observational data exist, particularly for ecosystems that have a long history of human intervention. Here, we combine quantitative summer and winter climate reconstructions, climate model simulations and proxies for three major environmental pressures (land use, nutrients and erosion) to explore the system dynamics, resilience, and the role of disturbance regimes in varved eutrophic Lake Żabińskie since AD 1000. Comparison between regional and global climate simulations and quantitative climate reconstructions indicate that proxy data capture noticeably natural forced climate variability, while internal variability appears as the dominant source of climate variability in the climate model simulations during most parts of the last millennium. Using different multivariate analyses and change point detection techniques, we identify ecosystem changes through time and shifts between rather stable states and highly variable ones, as expressed by the proxies for land-use, erosion and productivity in the lake. Prior to AD 1600, the lake ecosystem was characterized by a high stability and resilience against considerable observed natural climate variability. In contrast, lake-ecosystem conditions started to fluctuate at high frequency across a broad range of states after AD 1600. The period AD 1748-1868 represents the phase with the strongest human disturbance of the ecosystem. Analyses of the frequency of change points in the multi-proxy dataset suggests that the last 400 years were highly variable and flickering with increasing vulnerability of the ecosystem to the combined effects of climate variability and anthropogenic disturbances. This led to significant rapid ecosystem transformations.

Residents' perceptions about surrogate decision makers' financial conflicts of interest in ventilator withdrawal.

PubMed

Wastila, Lisa J; Farber, Neil J

2014-05-01

There have been no studies to date that examine physicians' decisions to withdraw life-sustaining treatment for patients based on their surrogates' financial gain. The authors' objective was to ascertain physician attitudes about withdrawing life-sustaining treatment when financial considerations are involved. A survey was developed and pretested containing eight scenarios in which a terminally ill patient's spouse had a decision to make regarding withdrawal of the ventilator, which was deemed medically futile. Nested variables included agreement or disagreement between the spouse and patient, decision to withdraw or continue the ventilator, and financial gain or no financial gain for the spouse. The authors surveyed all internal medicine residents at the University of California, San Diego in the autumn of 2011 and winter of 2012. The responses on each of the three variables for which respondents were likely to withdraw the ventilator were analyzed via student's t-tests. Residents were more likely to withdraw the ventilator when requested to do so than when it was requested to be continued. They were also more likely to withdraw the ventilator when there was agreement in the decision between the spouse and the patient. Residents were more likely to withdraw the ventilator when the spouse would not benefit financially. Internal medicine residents make some decisions about whether to withdraw life-sustaining treatment based on financial considerations. There needs to be ongoing communication with residents about end-of-life decisions where conflicts may exist between the surrogate decision makers and patients or physicians.

Effects of structural heterogeneity on frictional heating from biomarker thermal maturity analysis of the Muddy Mountain thrust, Nevada, USA

NASA Astrophysics Data System (ADS)

Coffey, G. L.; Savage, H. M.; Polissar, P. J.; Rowe, C. D.

2017-12-01

Faults are generally heterogeneous along-strike, with changes in thickness and structural complexity that should influence coseismic slip. However, observational limitations (e.g. limited outcrop or borehole samples) can obscure this complexity. Here we investigate the heterogeneity of frictional heating determined from biomarker thermal maturity and microstructural observations along a well-exposed fault to understand whether coseismic stress and frictional heating are related to structural complexity. We focus on the Muddy Mountain thrust, Nevada, a Sevier-age structure that has continuous exposure of its fault core and considerable structural variability for up to 50 m, to explore the distribution of earthquake slip and temperature rise along strike. We present new biomarker thermal maturity results that capture the heating history of fault rocks. Biomarkers are organic molecules produced by living organisms and preserved in the rock record. During heating, their structure is altered systematically with increasing time and temperature. Preliminary results show significant variability in thermal maturity along-strike at the Muddy Mountain thrust, suggesting differences in coseismic temperature rise on the meter- scale. Temperatures upwards of 500°C were generated in the principal slip zone at some locations, while in others, no significant temperature rise occurred. These results demonstrate that stress or slip heterogeneity occurred along the Muddy Mountain thrust at the meter-scale and considerable along-strike complexity existed, highlighting the importance of careful interpretation of whole-fault behavior from observations at a single point on a fault.

Towards an Effective Health Interventions Design: An Extension of the Health Belief Model

PubMed Central

Orji, Rita; Vassileva, Julita; Mandryk, Regan

2012-01-01

Introduction The recent years have witnessed a continuous increase in lifestyle related health challenges around the world. As a result, researchers and health practitioners have focused on promoting healthy behavior using various behavior change interventions. The designs of most of these interventions are informed by health behavior models and theories adapted from various disciplines. Several health behavior theories have been used to inform health intervention designs, such as the Theory of Planned Behavior, the Transtheoretical Model, and the Health Belief Model (HBM). However, the Health Belief Model (HBM), developed in the 1950s to investigate why people fail to undertake preventive health measures, remains one of the most widely employed theories of health behavior. However, the effectiveness of this model is limited. The first limitation is the low predictive capacity (R2 < 0.21 on average) of existing HBM’s variables coupled with the small effect size of individual variables. The second is lack of clear rules of combination and relationship between the individual variables. In this paper, we propose a solution that aims at addressing these limitations as follows: (1) we extended the Health Belief Model by introducing four new variables: Self-identity, Perceived Importance, Consideration of Future Consequences, and Concern for Appearance as possible determinants of healthy behavior. (2) We exhaustively explored the relationships/interactions between the HBM variables and their effect size. (3) We tested the validity of both our proposed extended model and the original HBM on healthy eating behavior. Finally, we compared the predictive capacity of the original HBM model and our extended model. Methods: To achieve the objective of this paper, we conducted a quantitative study of 576 participants’ eating behavior. Data for this study were collected over a period of one year (from August 2011 to August 2012). The questionnaire consisted of validated scales assessing the HBM determinants – perceived benefit, barrier, susceptibility, severity, cue to action, and self-efficacy – using 7-point Likert scale. We also assessed other health determinants such as consideration of future consequences, self-identity, concern for appearance and perceived importance. To analyses our data, we employed factor analysis and Partial Least Square Structural Equation Model (PLS-SEM) to exhaustively explore the interaction/relationship between the determinants and healthy eating behavior. We tested for the validity of both our proposed extended model and the original HBM on healthy eating behavior. Finally, we compared the predictive capacity of the original HBM model and our extended model and investigated possible mediating effects. Results: The results show that the three newly added determinants are better predictors of healthy behavior. Our extended HBM model lead to approximately 78% increase (from 40 to 71%) in predictive capacity compared to the old model. This shows the suitability of our extended HBM for use in predicting healthy behavior and in informing health intervention design. The results from examining possible relationships between the determinants in our model lead to an interesting discovery of some mediating relationships between the HBM’s determinants, therefore, shedding light on some possible combinations of determinants that could be employed by intervention designers to increase the effectiveness of their design. Conclusion: Consideration of future consequences, self-identity, concern for appearance, perceived importance, self-efficacy, perceived susceptibility are significant determinants of healthy eating behavior that can be manipulated by healthy eating intervention design. Most importantly, the result from our model established the existence of some mediating relationships among the determinants. The knowledge of both the direct and indirect relationships sheds some light on the possible combination rules. PMID:23569653

Influential input classification in probabilistic multimedia models

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

Maddalena, Randy L.; McKone, Thomas E.; Hsieh, Dennis P.H.

1999-05-01

Monte Carlo analysis is a statistical simulation method that is often used to assess and quantify the outcome variance in complex environmental fate and effects models. Total outcome variance of these models is a function of (1) the uncertainty and/or variability associated with each model input and (2) the sensitivity of the model outcome to changes in the inputs. To propagate variance through a model using Monte Carlo techniques, each variable must be assigned a probability distribution. The validity of these distributions directly influences the accuracy and reliability of the model outcome. To efficiently allocate resources for constructing distributions onemore » should first identify the most influential set of variables in the model. Although existing sensitivity and uncertainty analysis methods can provide a relative ranking of the importance of model inputs, they fail to identify the minimum set of stochastic inputs necessary to sufficiently characterize the outcome variance. In this paper, we describe and demonstrate a novel sensitivity/uncertainty analysis method for assessing the importance of each variable in a multimedia environmental fate model. Our analyses show that for a given scenario, a relatively small number of input variables influence the central tendency of the model and an even smaller set determines the shape of the outcome distribution. For each input, the level of influence depends on the scenario under consideration. This information is useful for developing site specific models and improving our understanding of the processes that have the greatest influence on the variance in outcomes from multimedia models.« less

Characterizing individual differences in functional connectivity using dual-regression and seed-based approaches.

PubMed

Smith, David V; Utevsky, Amanda V; Bland, Amy R; Clement, Nathan; Clithero, John A; Harsch, Anne E W; McKell Carter, R; Huettel, Scott A

2014-07-15

A central challenge for neuroscience lies in relating inter-individual variability to the functional properties of specific brain regions. Yet, considerable variability exists in the connectivity patterns between different brain areas, potentially producing reliable group differences. Using sex differences as a motivating example, we examined two separate resting-state datasets comprising a total of 188 human participants. Both datasets were decomposed into resting-state networks (RSNs) using a probabilistic spatial independent component analysis (ICA). We estimated voxel-wise functional connectivity with these networks using a dual-regression analysis, which characterizes the participant-level spatiotemporal dynamics of each network while controlling for (via multiple regression) the influence of other networks and sources of variability. We found that males and females exhibit distinct patterns of connectivity with multiple RSNs, including both visual and auditory networks and the right frontal-parietal network. These results replicated across both datasets and were not explained by differences in head motion, data quality, brain volume, cortisol levels, or testosterone levels. Importantly, we also demonstrate that dual-regression functional connectivity is better at detecting inter-individual variability than traditional seed-based functional connectivity approaches. Our findings characterize robust-yet frequently ignored-neural differences between males and females, pointing to the necessity of controlling for sex in neuroscience studies of individual differences. Moreover, our results highlight the importance of employing network-based models to study variability in functional connectivity. Copyright © 2014 Elsevier Inc. All rights reserved.

Surfing wave climate variability

NASA Astrophysics Data System (ADS)

Espejo, Antonio; Losada, Iñigo J.; Méndez, Fernando J.

2014-10-01

International surfing destinations are highly dependent on specific combinations of wind-wave formation, thermal conditions and local bathymetry. Surf quality depends on a vast number of geophysical variables, and analyses of surf quality require the consideration of the seasonal, interannual and long-term variability of surf conditions on a global scale. A multivariable standardized index based on expert judgment is proposed for this purpose. This index makes it possible to analyze surf conditions objectively over a global domain. A summary of global surf resources based on a new index integrating existing wave, wind, tides and sea surface temperature databases is presented. According to general atmospheric circulation and swell propagation patterns, results show that west-facing low to middle-latitude coasts are more suitable for surfing, especially those in the Southern Hemisphere. Month-to-month analysis reveals strong seasonal variations in the occurrence of surfable events, enhancing the frequency of such events in the North Atlantic and the North Pacific. Interannual variability was investigated by comparing occurrence values with global and regional modes of low-frequency climate variability such as El Niño and the North Atlantic Oscillation, revealing their strong influence at both the global and the regional scale. Results of the long-term trends demonstrate an increase in the probability of surfable events on west-facing coasts around the world in recent years. The resulting maps provide useful information for surfers, the surf tourism industry and surf-related coastal planners and stakeholders.

The performance-variability paradox, financial decision making, and the curious case of negative Hurst exponents.

PubMed

Guastello, Stephen J; Reiter, Katherine; Shircel, Anton; Timm, Paul; Malon, Matthew; Fabisch, Megan

2014-07-01

This study examined the relationship between performance variability and actual performance of financial decision makers who were working under experimental conditions of increasing workload and fatigue. The rescaled range statistic, also known as the Hurst exponent (H) was used as an index of variability. Although H is defined as having a range between 0 and 1, 45% of the 172 time series generated by undergraduates were negative. Participants in the study chose the optimum investment out of sets of 3 to 5 options that were presented a series of 350 displays. The sets of options varied in both the complexity of the options and number of options under simultaneous consideration. One experimental condition required participants to make their choices within 15 sec, and the other condition required them to choose within 7.5 sec. Results showed that (a) negative H was possible and not a result of psychometric error; (b) negative H was associated with negative autocorrelations in a time series. (c) H was the best predictor of performance of the variables studied; (d) three other significant predictors were scores on an anagrams test and ratings of physical demands and performance demands; (e) persistence as evidenced by the autocorrelations was associated with ratings of greater time pressure. It was concluded, furthermore, that persistence and overall performance were correlated, that 'healthy' variability only exists within a limited range, and other individual differences related to ability and resistance to stress or fatigue are also involved in the prediction of performance.

Planning long lasting insecticide treated net campaigns: should households’ existing nets be taken into account?

PubMed Central

2013-01-01

Background Mass distribution of long-lasting insecticide treated bed nets (LLINs) has led to large increases in LLIN coverage in many African countries. As LLIN ownership levels increase, planners of future mass distributions face the challenge of deciding whether to ignore the nets already owned by households or to take these into account and attempt to target individuals or households without nets. Taking existing nets into account would reduce commodity costs but require more sophisticated, and potentially more costly, distribution procedures. The decision may also have implications for the average age of nets in use and therefore on the maintenance of universal LLIN coverage over time. Methods A stochastic simulation model based on the NetCALC algorithm was used to determine the scenarios under which it would be cost saving to take existing nets into account, and the potential effects of doing so on the age profile of LLINs owned. The model accounted for variability in timing of distributions, concomitant use of continuous distribution systems, population growth, sampling error in pre-campaign coverage surveys, variable net ‘decay’ parameters and other factors including the feasibility and accuracy of identifying existing nets in the field. Results Results indicate that (i) where pre-campaign coverage is around 40% (of households owning at least 1 LLIN), accounting for existing nets in the campaign will have little effect on the mean age of the net population and (ii) even at pre-campaign coverage levels above 40%, an approach that reduces LLIN distribution requirements by taking existing nets into account may have only a small chance of being cost-saving overall, depending largely on the feasibility of identifying nets in the field. Based on existing literature the epidemiological implications of such a strategy is likely to vary by transmission setting, and the risks of leaving older nets in the field when accounting for existing nets must be considered. Conclusions Where pre-campaign coverage levels established by a household survey are below 40% we recommend that planners do not take such LLINs into account and instead plan a blanket mass distribution. At pre-campaign coverage levels above 40%, campaign planners should make explicit consideration of the cost and feasibility of accounting for existing LLINs before planning blanket mass distributions. Planners should also consider restricting the coverage estimates used for this decision to only include nets under two years of age in order to ensure that old and damaged nets do not compose too large a fraction of existing net coverage. PMID:23763773

Planning long lasting insecticide treated net campaigns: should households' existing nets be taken into account?

PubMed

Yukich, Joshua; Bennett, Adam; Keating, Joseph; Yukich, Rudy K; Lynch, Matt; Eisele, Thomas P; Kolaczinski, Kate

2013-06-14

Mass distribution of long-lasting insecticide treated bed nets (LLINs) has led to large increases in LLIN coverage in many African countries. As LLIN ownership levels increase, planners of future mass distributions face the challenge of deciding whether to ignore the nets already owned by households or to take these into account and attempt to target individuals or households without nets. Taking existing nets into account would reduce commodity costs but require more sophisticated, and potentially more costly, distribution procedures. The decision may also have implications for the average age of nets in use and therefore on the maintenance of universal LLIN coverage over time. A stochastic simulation model based on the NetCALC algorithm was used to determine the scenarios under which it would be cost saving to take existing nets into account, and the potential effects of doing so on the age profile of LLINs owned. The model accounted for variability in timing of distributions, concomitant use of continuous distribution systems, population growth, sampling error in pre-campaign coverage surveys, variable net 'decay' parameters and other factors including the feasibility and accuracy of identifying existing nets in the field. Results indicate that (i) where pre-campaign coverage is around 40% (of households owning at least 1 LLIN), accounting for existing nets in the campaign will have little effect on the mean age of the net population and (ii) even at pre-campaign coverage levels above 40%, an approach that reduces LLIN distribution requirements by taking existing nets into account may have only a small chance of being cost-saving overall, depending largely on the feasibility of identifying nets in the field. Based on existing literature the epidemiological implications of such a strategy is likely to vary by transmission setting, and the risks of leaving older nets in the field when accounting for existing nets must be considered. Where pre-campaign coverage levels established by a household survey are below 40% we recommend that planners do not take such LLINs into account and instead plan a blanket mass distribution. At pre-campaign coverage levels above 40%, campaign planners should make explicit consideration of the cost and feasibility of accounting for existing LLINs before planning blanket mass distributions. Planners should also consider restricting the coverage estimates used for this decision to only include nets under two years of age in order to ensure that old and damaged nets do not compose too large a fraction of existing net coverage.

Reproducibility of Interferon Gamma (IFN-γ) Release Assays. A Systematic Review

PubMed Central

Tagmouti, Saloua; Slater, Madeline; Benedetti, Andrea; Kik, Sandra V.; Banaei, Niaz; Cattamanchi, Adithya; Metcalfe, John; Dowdy, David; van Zyl Smit, Richard; Dendukuri, Nandini

2014-01-01

Rationale: Interferon gamma (IFN-γ) release assays for latent tuberculosis infection result in a larger-than-expected number of conversions and reversions in occupational screening programs, and reproducibility of test results is a concern. Objectives: Knowledge of the relative contribution and extent of the individual sources of variability (immunological, preanalytical, or analytical) could help optimize testing protocols. Methods: We performed a systematic review of studies published by October 2013 on all potential sources of variability of commercial IFN-γ release assays (QuantiFERON-TB Gold In-Tube and T-SPOT.TB). The included studies assessed test variability under identical conditions and under different conditions (the latter both overall and stratified by individual sources of variability). Linear mixed effects models were used to estimate within-subject SD. Measurements and Main Results: We identified a total of 26 articles, including 7 studies analyzing variability under the same conditions, 10 studies analyzing variability with repeat testing over time under different conditions, and 19 studies reporting individual sources of variability. Most data were on QuantiFERON (only three studies on T-SPOT.TB). A considerable number of conversions and reversions were seen around the manufacturer-recommended cut-point. The estimated range of variability of IFN-γ response in QuantiFERON under identical conditions was ±0.47 IU/ml (coefficient of variation, 13%) and ±0.26 IU/ml (30%) for individuals with an initial IFN-γ response in the borderline range (0.25–0.80 IU/ml). The estimated range of variability in noncontrolled settings was substantially larger (±1.4 IU/ml; 60%). Blood volume inoculated into QuantiFERON tubes and preanalytic delay were identified as key sources of variability. Conclusions: This systematic review shows substantial variability with repeat IFN-γ release assays testing even under identical conditions, suggesting that reversions and conversions around the existing cut-point should be interpreted with caution. PMID:25188809

An improved method to represent DEM uncertainty in glacial lake outburst flood propagation using stochastic simulations

NASA Astrophysics Data System (ADS)

Watson, Cameron S.; Carrivick, Jonathan; Quincey, Duncan

2015-10-01

Modelling glacial lake outburst floods (GLOFs) or 'jökulhlaups', necessarily involves the propagation of large and often stochastic uncertainties throughout the source to impact process chain. Since flood routing is primarily a function of underlying topography, communication of digital elevation model (DEM) uncertainty should accompany such modelling efforts. Here, a new stochastic first-pass assessment technique was evaluated against an existing GIS-based model and an existing 1D hydrodynamic model, using three DEMs with different spatial resolution. The analysis revealed the effect of DEM uncertainty and model choice on several flood parameters and on the prediction of socio-economic impacts. Our new model, which we call MC-LCP (Monte Carlo Least Cost Path) and which is distributed in the supplementary information, demonstrated enhanced 'stability' when compared to the two existing methods, and this 'stability' was independent of DEM choice. The MC-LCP model outputs an uncertainty continuum within its extent, from which relative socio-economic risk can be evaluated. In a comparison of all DEM and model combinations, the Shuttle Radar Topography Mission (SRTM) DEM exhibited fewer artefacts compared to those with the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model (ASTER GDEM), and were comparable to those with a finer resolution Advanced Land Observing Satellite Panchromatic Remote-sensing Instrument for Stereo Mapping (ALOS PRISM) derived DEM. Overall, we contend that the variability we find between flood routing model results suggests that consideration of DEM uncertainty and pre-processing methods is important when assessing flow routing and when evaluating potential socio-economic implications of a GLOF event. Incorporation of a stochastic variable provides an illustration of uncertainty that is important when modelling and communicating assessments of an inherently complex process.

Social and cultural sustainability: criteria, indicators, verifier variables for measurement and maps for visualization to support planning.

PubMed

Axelsson, Robert; Angelstam, Per; Degerman, Erik; Teitelbaum, Sara; Andersson, Kjell; Elbakidze, Marine; Drotz, Marcus K

2013-03-01

Policies on economic use of natural resources require considerations to social and cultural values. In order to make those concrete in a planning context, this paper aims to interpret social and cultural criteria, identify indicators, match these with verifier variables and visualize them on maps. Indicators were selected from a review of scholarly work and natural resource policies, and then matched with verifier variables available for Sweden's 290 municipalities. Maps of the spatial distribution of four social and four cultural verifier variables were then produced. Consideration of social and cultural values in the studied natural resource use sectors was limited. The spatial distribution of the verifier variables exhibited a general divide between northwest and south Sweden, and regional rural and urban areas. We conclude that it is possible to identify indicators and match them with verifier variables to support inclusion of social and cultural values in planning.

31 CFR Appendix C to Part 356 - Investment Considerations

Code of Federal Regulations, 2011 CFR

2011-07-01

... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false Investment Considerations C Appendix C..., App. C Appendix C to Part 356—Investment Considerations I. Inflation-Protected Securities A. Principal and Interest Variability An investment in securities with principal or interest determined by...

Using Animal Models to Determine the Role of Gustatory Neural Input in the Control of Ingestive Behavior and the Maintenance of Body Weight

PubMed Central

Ciullo, Dana L.

2015-01-01

Introduction Decades of research have suggested that nutritional intake contributes to the development of human disease, mainly by influencing the development of obesity and obesity-related conditions. A relatively large body of research indicates that functional variation in human taste perception can influence nutritional intake as well as body mass accumulation. However, there are a considerable number of studies that suggest that no link between these variables actually exists. These discrepancies in the literature likely result from the confounding influence of a variety of other, uncontrolled, factors that can influence ingestive behavior. Strategy In this review, the use of controlled animal experimentation to alleviate at least some of these issues related to the lack of control of experimental variables is discussed. Specific examples of the use of some of these techniques are examined. Discussion and conclusions The review will close with some specific suggestions aimed at strengthening the link between gustatory neural input and its putative influence on ingestive behaviors and the maintenance of body weight. PMID:26557212

Memory bias for threatening information in anxiety and anxiety disorders: a meta-analytic review.

PubMed

Mitte, Kristin

2008-11-01

Although some theories suggest that anxious individuals selectively remember threatening stimuli, findings remain contradictory despite a considerable amount of research. A quantitative integration of 165 studies with 9,046 participants (clinical and nonclinical samples) examined whether a memory bias exists and which moderator variables influence its magnitude. Implicit memory bias was investigated in lexical decision/stimulus identification and word-stem completion paradigms; explicit memory bias was investigated in recognition and recall paradigms. Overall, effect sizes showed no significant impact of anxiety on implicit memory and recognition. Analyses indicated a memory bias for recall, whose magnitude depended on experimental study procedures like the encoding procedure or retention interval. Anxiety influenced recollection of previous experiences; anxious individuals favored threat-related information. Across all paradigms, clinical status was not significantly linked to effect sizes, indicating no qualitative difference in information processing between anxiety patients and high-anxious persons. The large discrepancy between study effects in recall and recognition indicates that future research is needed to identify moderator variables for avoidant and preferred remembering.

SOS based robust H(∞) fuzzy dynamic output feedback control of nonlinear networked control systems.

PubMed

Chae, Seunghwan; Nguang, Sing Kiong

2014-07-01

In this paper, a methodology for designing a fuzzy dynamic output feedback controller for discrete-time nonlinear networked control systems is presented where the nonlinear plant is modelled by a Takagi-Sugeno fuzzy model and the network-induced delays by a finite state Markov process. The transition probability matrix for the Markov process is allowed to be partially known, providing a more practical consideration of the real world. Furthermore, the fuzzy controller's membership functions and premise variables are not assumed to be the same as the plant's membership functions and premise variables, that is, the proposed approach can handle the case, when the premise of the plant are not measurable or delayed. The membership functions of the plant and the controller are approximated as polynomial functions, then incorporated into the controller design. Sufficient conditions for the existence of the controller are derived in terms of sum of square inequalities, which are then solved by YALMIP. Finally, a numerical example is used to demonstrate the validity of the proposed methodology.

Mitochondrial threshold effects.

PubMed Central

Rossignol, Rodrigue; Faustin, Benjamin; Rocher, Christophe; Malgat, Monique; Mazat, Jean-Pierre; Letellier, Thierry

2003-01-01

The study of mitochondrial diseases has revealed dramatic variability in the phenotypic presentation of mitochondrial genetic defects. To attempt to understand this variability, different authors have studied energy metabolism in transmitochondrial cell lines carrying different proportions of various pathogenic mutations in their mitochondrial DNA. The same kinds of experiments have been performed on isolated mitochondria and on tissue biopsies taken from patients with mitochondrial diseases. The results have shown that, in most cases, phenotypic manifestation of the genetic defect occurs only when a threshold level is exceeded, and this phenomenon has been named the 'phenotypic threshold effect'. Subsequently, several authors showed that it was possible to inhibit considerably the activity of a respiratory chain complex, up to a critical value, without affecting the rate of mitochondrial respiration or ATP synthesis. This phenomenon was called the 'biochemical threshold effect'. More recently, quantitative analysis of the effects of various mutations in mitochondrial DNA on the rate of mitochondrial protein synthesis has revealed the existence of a 'translational threshold effect'. In this review these different mitochondrial threshold effects are discussed, along with their molecular bases and the roles that they play in the presentation of mitochondrial diseases. PMID:12467494

A statistical analysis of flank eruptions on Etna volcano

NASA Astrophysics Data System (ADS)

Mulargia, Francesco; Tinti, Stefano; Boschi, Enzo

1985-02-01

A singularly complete record exists for the eruptive activity of Etna volcano. The time series of occurrence of flank eruptions in the period 1600-1980, in which the record is presumably complete, is found to follow a stationary Poisson process. A revision of the available data shows that eruption durations are rather well correlated with the estimates of the volume of lava flows. This implies that the magnitude of an eruption can be defined directly by its duration. Extreme value statistics are then applied to the time series, using duration as a dependent variable. The probability of occurrence of a very long (300 days) eruption is greater than 50% only in time intervals of the order of 50 years. The correlation found between duration and total output also allows estimation of the probability of occurrence of a major event which exceeds a given duration and total flow of lava. The composite probabilities do not differ considerably from the pure ones. Paralleling a well established application to seismic events, extreme value theory can be profitably used in volcanic risk estimates, provided that appropriate account is also taken of all other variables.

Proficiency Testing for Evaluating Aerospace Materials Test Anomalies

NASA Technical Reports Server (NTRS)

Hirsch, D.; Motto, S.; Peyton, S.; Beeson, H.

2006-01-01

ASTM G 86 and ASTM G 74 are commonly used to evaluate materials susceptibility to ignition in liquid and gaseous oxygen systems. However, the methods have been known for their lack of repeatability. The inherent problems identified with the test logic would either not allow precise identification or the magnitude of problems related to running the tests, such as lack of consistency of systems performance, lack of adherence to procedures, etc. Excessive variability leads to increasing instances of accepting the null hypothesis erroneously, and so to the false logical deduction that problems are nonexistent when they really do exist. This paper attempts to develop and recommend an approach that could lead to increased accuracy in problem diagnostics by using the 50% reactivity point, which has been shown to be more repeatable. The initial tests conducted indicate that PTFE and Viton A (for pneumatic impact) and Buna S (for mechanical impact) would be good choices for additional testing and consideration for inter-laboratory evaluations. The approach presented could also be used to evaluate variable effects with increased confidence and tolerance optimization.

Bracketing mid-pliocene sea surface temperature: maximum and minimum possible warming

USGS Publications Warehouse

Dowsett, Harry

2004-01-01

Estimates of sea surface temperature (SST) from ocean cores reveal a warm phase of the Pliocene between about 3.3 and 3.0 Mega-annums (Ma). Pollen records from land based cores and sections, although not as well dated, also show evidence for a warmer climate at about the same time. Increased greenhouse forcing and altered ocean heat transport is the leading candidates for the underlying cause of Pliocene global warmth. However, despite being a period of global warmth, there exists considerable variability within this interval. Two new SST reconstructions have been created to provide a climatological error bar for warm peak phases of the Pliocene. These data represent the maximum and minimum possible warming recorded within the 3.3 to 3.0 Ma interval.

Adding Concrete Syntax to a Prolog-Based Program Synthesis System

NASA Technical Reports Server (NTRS)

Fischer, Bernd; Visser, Eelco

2003-01-01

Program generation and transformation systems manipulate large, pa- rameterized object language fragments. Support for user-definable concrete syntax makes this easier but is typically restricted to certain object and meta languages. We show how Prolog can be retrofitted with concrete syntax and describe how a seamless interaction of concrete syntax fragments with an existing legacy meta-programming system based on abstract syntax is achieved. We apply the approach to gradually migrate the schemas of the AUTOBAYES program synthesis system to concrete syntax. Fit experiences show that this can result in a considerable reduction of the code size and an improved readability of the code. In particular, abstracting out fresh-variable generation and second-order term construction allows the formulation of larger continuous fragments and improves the locality in the schemas.

Future translational applications from the contemporary genomics era: a scientific statement from the American Heart Association.

PubMed

Fox, Caroline S; Hall, Jennifer L; Arnett, Donna K; Ashley, Euan A; Delles, Christian; Engler, Mary B; Freeman, Mason W; Johnson, Julie A; Lanfear, David E; Liggett, Stephen B; Lusis, Aldons J; Loscalzo, Joseph; MacRae, Calum A; Musunuru, Kiran; Newby, L Kristin; O'Donnell, Christopher J; Rich, Stephen S; Terzic, Andre

2015-05-12

The field of genetics and genomics has advanced considerably with the achievement of recent milestones encompassing the identification of many loci for cardiovascular disease and variable drug responses. Despite this achievement, a gap exists in the understanding and advancement to meaningful translation that directly affects disease prevention and clinical care. The purpose of this scientific statement is to address the gap between genetic discoveries and their practical application to cardiovascular clinical care. In brief, this scientific statement assesses the current timeline for effective translation of basic discoveries to clinical advances, highlighting past successes. Current discoveries in the area of genetics and genomics are covered next, followed by future expectations, tools, and competencies for achieving the goal of improving clinical care. © 2015 American Heart Association, Inc.

Multiannual forecasting of seasonal influenza dynamics reveals climatic and evolutionary drivers.

PubMed

Axelsen, Jacob Bock; Yaari, Rami; Grenfell, Bryan T; Stone, Lewi

2014-07-01

Human influenza occurs annually in most temperate climatic zones of the world, with epidemics peaking in the cold winter months. Considerable debate surrounds the relative role of epidemic dynamics, viral evolution, and climatic drivers in driving year-to-year variability of outbreaks. The ultimate test of understanding is prediction; however, existing influenza models rarely forecast beyond a single year at best. Here, we use a simple epidemiological model to reveal multiannual predictability based on high-quality influenza surveillance data for Israel; the model fit is corroborated by simple metapopulation comparisons within Israel. Successful forecasts are driven by temperature, humidity, antigenic drift, and immunity loss. Essentially, influenza dynamics are a balance between large perturbations following significant antigenic jumps, interspersed with nonlinear epidemic dynamics tuned by climatic forcing.

Model distribution of Silver Chub (Macrhybopsis storeriana) in western Lake Erie

USGS Publications Warehouse

McKenna, James E.; Castiglione, Chris

2014-01-01

Silver Chub (Macrhybopsis storeriana) was once a common forage fish in Lake Erie but has declined greatly since the 1950s. Identification of optimal and marginal habitats would help conserve and manage this species. We developed neural networks to use broad-scale habitat variables to predict abundance classes of Silver Chub in western Lake Erie, where its largest remaining population exists. Model performance was good, particularly for predicting locations of habitat with the potential to support the highest and lowest abundances of this species. Highest abundances are expected in waters >5 m deep; water depth and distance to coastal habitats were important model features. These models provide initial tools to help conserve this species, but their resolution can be improved with additional data and consideration of other ecological factors.

Revisiting gender, race, and ear differences in peripheral auditory function

NASA Astrophysics Data System (ADS)

Boothalingam, Sriram; Klyn, Niall A. M.; Stiepan, Samantha M.; Wilson, Uzma S.; Lee, Jungwha; Siegel, Jonathan H.; Dhar, Sumitrajit

2018-05-01

Various measures of auditory function are reported to be superior in females as compared to males, in African American compared to Caucasian individuals, and in right compared to left ears. We re-examined the influence of these subject variables on hearing thresholds and otoacoustic emissions (OAEs) in a sample of 887 human participants between 10 and 68 years of age. Even though the variables of interest here have been examined before, previous attempts have largely been limited to frequencies up to 8 kHz. We used state-of-the-art signal delivery and recording techniques that compensated for individual differences in ear canal acoustics, allowing us to measure hearing thresholds and OAEs up to 20 kHz. The use of these modern calibration and recording techniques provided the motivation for re-examining these commonly studied variables. While controlling for age, noise exposure history, and general health history, we attempted to isolate the effects of gender, race, and ear (left versus right) on hearing thresholds and OAEs. Our results challenge the notion of a right ear advantage and question the existence of a significant gender and race differences in both hearing thresholds and OAE levels. These results suggest that ear canal anatomy and acoustics should be important considerations when evaluating the influence of gender, race, and ear on peripheral auditory function.

Assessment of chemical and genetic variability in Tanacetum gracile accessions collected from cold desert of Western Himalaya.

PubMed

Mahajan, Vidushi; Chouhan, Rekha; Kitchlu, Surinder; Bindu, Kushal; Koul, Sushma; Singh, Bikarma; Bedi, Yashbir S; Gandhi, Sumit G

2018-06-01

Genetic diversity is essential for survival and adaptation of high altitude plants such as those of Tanacetum genus, which are constantly exposed to environmental stress. We collected flowering shoots of ten accessions of Tanacetum gracile Hook.f. & Thomson (Asteraceae) (Tg 1-Tg 10), from different regions of cold desert of Western Himalaya. Chemical profile of the constituents, as inferred from GC-MS, exhibited considerable variability. Percentage yield of essential oil ranged from 0.2 to 0.75% (dry-weight basis) amongst different accessions. Tg 1 and Tg 6 were found to produce high yields of camphor (46%) and lavandulol (41%), respectively. Alpha -phellendrene, alpha -bisabool, p -cymene and chamazulene were the main oil components in other accessions. Genetic variability among the accessions was studied using RAPD markers as well as by sequencing and analyzing nuclear 18S rDNA, and plastid rbcL and matK loci. The polymorphic information content (PIC) of RAPD markers ranged from 0.18 to 0.5 and the analysis clustered the accessions into two major clades. The present study emphasized the importance of survey, collection, and conservation of naturally existing chemotypes of medicinal and aromatic plants, considering their potential use in aroma and pharmaceutical industry.

Accelerating simulation for the multiple-point statistics algorithm using vector quantization

NASA Astrophysics Data System (ADS)

Zuo, Chen; Pan, Zhibin; Liang, Hao

2018-03-01

Multiple-point statistics (MPS) is a prominent algorithm to simulate categorical variables based on a sequential simulation procedure. Assuming training images (TIs) as prior conceptual models, MPS extracts patterns from TIs using a template and records their occurrences in a database. However, complex patterns increase the size of the database and require considerable time to retrieve the desired elements. In order to speed up simulation and improve simulation quality over state-of-the-art MPS methods, we propose an accelerating simulation for MPS using vector quantization (VQ), called VQ-MPS. First, a variable representation is presented to make categorical variables applicable for vector quantization. Second, we adopt a tree-structured VQ to compress the database so that stationary simulations are realized. Finally, a transformed template and classified VQ are used to address nonstationarity. A two-dimensional (2D) stationary channelized reservoir image is used to validate the proposed VQ-MPS. In comparison with several existing MPS programs, our method exhibits significantly better performance in terms of computational time, pattern reproductions, and spatial uncertainty. Further demonstrations consist of a 2D four facies simulation, two 2D nonstationary channel simulations, and a three-dimensional (3D) rock simulation. The results reveal that our proposed method is also capable of solving multifacies, nonstationarity, and 3D simulations based on 2D TIs.

Where You Live Matters: Localising Environmental Impacts on Health, Nutrition and Poverty in Cambodia Using Small Area Estimation Techniques

NASA Astrophysics Data System (ADS)

Nilsen, K.; van Soesbergen, A.; Matthews, Z.

2016-12-01

Socioeconomic development depends on local environments. However, the scientific evidence quantifying the impact of environmental factors on health, nutrition and poverty at subnational levels is limited. This is because socioeconomic indicators are derived from sample surveys representative only at aggregate levels compared to environmental variables mostly available in high-resolution grids. Cambodia was selected because of its commitment to development in the context of a rapidly deteriorating environment. Having made considerable progress since 2005, access to health services is limited, a quarter of the population is still poor and 40% rural children are malnourished. Cambodia is also facing considerable environmental challenges including high deforestation rates, land degradation and natural hazards. Addressing existing gaps in the knowledge of environmental impacts on health and livelihoods, this study applies small area estimation (SAE) to quantify health, nutritional and poverty outcomes in the context of local environments. SAE produces reliable subnational estimates of socioeconomic outcomes available only from sample surveys by combining them with information from auxiliary sources (census). A model is used to explain common trades across areas and a random effect structure is applied to explain the observed extra heterogeneity. SAE models predicting health, nutrition and poverty outcomes excluding and including contextual environmental variables on natural hazards vulnerability, forest cover, climate, and agricultural production are compared. Results are mapped at regional and district levels to spatially assess the impacts of environmental variation on the outcomes. Inter and intra-regional inequalities are also estimated to examine the efficacy of health/socioeconomic policy targeting based on geographic location. Preliminary results suggest that localised environmental factors have considerable impacts on the indicators estimated and should therefore not be ignored. While there are large regional differences, pockets of malnutrition, poverty and inequitable health outcomes within regions are identified. The inequality decomposition shows under and over-coverage of geographical targeting when environmental factors are taken into account.

[Shortage and need of physicians in Germany? Questions addressed to health services research].

PubMed

Adler, G; v d Knesebeck, J-H

2011-02-01

The problem of shortage of physicians has been discussed controversially in Germany for years, and the different positions of the interest groups involved have not been resolved. The question of the present and anticipated future requirement of physicians is central for an appropriate and necessary medical care of the population. In the analysis, supply and demand of medical care have to be distinguished. Relatively reliable data do exist for the supply of physicians; however, the changing number of working hours that male and--in particular female--physicians are willing to contribute should be taken into consideration. Reliable data for the future demand are presently not available. Several variables (e.g., demography, disease spectrum of an aging society, medical progress, the changing rules of working hours, and the shift of medical care between hospital and practice care) depend on future developments. Considering the existing serious indicators of a growing shortage of physicians, it is recommended to put more effort into the scientific investigation of these factors. More profound data should improve the basis for decisions in health and education politics.

A Framework for Integrating Implicit Bias Recognition Into Health Professions Education.

PubMed

Sukhera, Javeed; Watling, Chris

2018-01-01

Existing literature on implicit bias is fragmented and comes from a variety of fields like cognitive psychology, business ethics, and higher education, but implicit-bias-informed educational approaches have been underexplored in health professions education and are difficult to evaluate using existing tools. Despite increasing attention to implicit bias recognition and management in health professions education, many programs struggle to meaningfully integrate these topics into curricula. The authors propose a six-point actionable framework for integrating implicit bias recognition and management into health professions education that draws on the work of previous researchers and includes practical tools to guide curriculum developers. The six key features of this framework are creating a safe and nonthreatening learning context, increasing knowledge about the science of implicit bias, emphasizing how implicit bias influences behaviors and patient outcomes, increasing self-awareness of existing implicit biases, improving conscious efforts to overcome implicit bias, and enhancing awareness of how implicit bias influences others. Important considerations for designing implicit-bias-informed curricula-such as individual and contextual variables, as well as formal and informal cultural influences-are discussed. The authors also outline assessment and evaluation approaches that consider outcomes at individual, organizational, community, and societal levels. The proposed framework may facilitate future research and exploration regarding the use of implicit bias in health professions education.

Attitudes and Approaches for Withdrawing Drugs for Children with Clinically Inactive Nonsystemic JIA: A Survey of the Childhood Arthritis and Rheumatology Research Alliance.

PubMed

Horton, Daniel B; Onel, Karen B; Beukelman, Timothy; Ringold, Sarah

2017-03-01

To assess the attitudes and strategies of pediatric rheumatology clinicians toward withdrawing medications for children with clinically inactive juvenile idiopathic arthritis (JIA). Members of the Childhood Arthritis and Rheumatology Research Alliance (CARRA) completed an anonymous electronic survey on decision making and approaches for withdrawing medications for inactive nonsystemic JIA. Data were analyzed using descriptive statistics. Of 388 clinicians in CARRA, 124 completed surveys (32%), predominantly attending pediatric rheumatologists. The most highly ranked factors in decision making for withdrawing medications were the duration of clinical inactivity, drug toxicity, duration of prior activity, patient/family preferences, joint damage, and JIA category. Diagnoses of rheumatoid factor-positive polyarthritis and persistent oligoarthritis made respondents less likely and more likely, respectively, to withdraw JIA medications. Three-quarters of respondents waited for 6-12 months of inactive disease before stopping methotrexate (MTX) or biologics, but preferences varied. There was also considerable variability in the strategies used to reduce, taper, or stop medications for clinically inactive JIA; most commonly, clinicians reported slow medication tapers lasting at least 2 months. For children receiving combination MTX-biologic therapy, 63% of respondents preferred stopping MTX first. Most clinicians reported using imaging only seldom or sometimes to guide decision making, but most were also reluctant to withdraw medications in the presence of asymptomatic imaging abnormalities suggestive of subclinical inflammation. Considerable variability exists among pediatric rheumatology clinicians regarding when and how to withdraw medications for children with clinically inactive JIA. More research is needed to identify the most effective approaches to withdraw medications and predictors of outcomes.

40 CFR 230.91 - Purpose and general considerations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... done after taking into consideration cost, existing technology, and logistics in light of overall... national or regional level. No modifications to the basic application, meaning, or intent of this subpart...

On X-Ray Variability in Seyfert Galaxies

NASA Technical Reports Server (NTRS)

Turner, T. J.; George, I. M.; Nandra, K.; Turcan, D.

1999-01-01

This paper presents a quantification of the X-ray variability amplitude for 79 ASCA observations of 36 Seyfert 1 galaxies. We find that consideration of sources with the narrowest permitted lines in the optical band introduces scatter into the established correlation between X-ray variability and nuclear luminosity. Consideration of the X-ray spectral index and variability properties together shows distinct groupings in parameter space for broad and narrow-line Seyfert 1 galaxies, confirming previous studies. A strong correlation is found between hard X-ray variability and FWHM Hbeta. A range of nuclear mass and accretion rate across the Seyfert population can explain the differences observed in X-ray and optical properties. An attractive alternative model, which does not depend on any systematic difference in central mass, is that the circumnuclear gas of NLSy1s is different to BLSy1s in temperature, optical depth, density or geometry.

Variables related to romanticism and self-esteem in pregnant teenagers.

PubMed

Medora, N P; Goldstein, A; von der Hellen, C

1993-01-01

In this study, the Dean Romanticism Scale and the Bachman Self-esteem Scale were administered to 121 teenagers between the ages of 12 and 19 in Southern California to investigate their degree of romanticism and self-esteem. The study also explored whether there was any relationship between the dependent variables of romanticism and self-esteem and ten independent variables--age, race, place of residence during pregnancy, age when first sexual intercourse occurred, age when pregnancy occurred, incidence of sexual abuse, incidence of abortion, adoption considerations, whether the subject was currently sexually active, and whether the teenager planned to have a child with the father of the baby. The results indicated that two variables were significantly related to feelings of romanticism--adoption considerations and whether the adolescent planned to have a child with the baby's father. In addition, two variables were significantly related to self-esteem--the incidence of sexual abuse and the incidence of abortion.

The role of population monitoring in the management of North American waterfowl

USGS Publications Warehouse

Nichols, J.D.; Williams, B.K.; Johnson, F.A.

2000-01-01

Despite the effort and expense devoted to large-scale monitoring programs, few existing programs have been designed with specific objectives in mind and few permit strong inferences about the dynamics of monitored systems. The waterfowl population monitoring programs of the U.S. Fish and Wildlife Service, Canadian Wildlife Service and state and provincial agencies provide a nice example with respect to program objectives, design and implementation. The May Breeding Grounds Survey provides an estimate of system state (population size) that serves two primary purposes in the adaptive management process: identifying the appropriate time-specific management actions and updating the information state (model weights) by providing a basis for evaluating predictions of competing models. Other waterfowl monitoring programs (e.g., banding program, hunter questionnaire survey, parts collection survey, winter survey) provide estimates of vital rates (rates of survival, reproduction and movement) associated with system dynamics and variables associated with management objectives (e.g., harvest). The reliability of estimates resulting from monitoring programs depends strongly on whether considerations about spatial variation and detection probability have been adequately incorporated into program design and implementation. Certain waterfowl surveys again provide nice examples of monitoring programs that incorporate these considerations.

The nuclear 18S ribosomal RNA gene as a source of phylogenetic information in the genus Taenia.

PubMed

Yan, Hongbin; Lou, Zhongzi; Li, Li; Ni, Xingwei; Guo, Aijiang; Li, Hongmin; Zheng, Yadong; Dyachenko, Viktor; Jia, Wanzhong

2013-03-01

Most species of the genus Taenia are of considerable medical and veterinary significance. In this study, complete nuclear 18S rRNA gene sequences were obtained from seven members of genus Taenia [Taenia multiceps, Taenia saginata, Taenia asiatica, Taenia solium, Taenia pisiformis, Taenia hydatigena, and Taenia taeniaeformis] and a phylogeny inferred using these sequences. Most of the variable sites fall within the variable regions, V1-V5. We show that sequences from the nuclear 18S ribosomal RNA gene have considerable promise as sources of phylogenetic information within the genus Taenia. Furthermore, given that almost all the variable sites lie within defined variable portions of that gene, it will be appropriate and economical to sequence only those regions for additional species of Taenia.

Socioeconomic and Cultural Correlates of Diet Quality in the Canadian Arctic: Results from the 2007-2008 Inuit Health Survey.

PubMed

Galloway, Tracey; Johnson-Down, Louise; Egeland, Grace M

2015-09-01

We examined the impact of socioeconomic and cultural factors on dietary quality in adult Inuit living in the Canadian Arctic. Interviews and a 24-h dietary recall were administered to 805 men and 1292 women from Inuit regions in the Canadian Arctic. We examined the effect of age, sex, education, income, employment, and cultural variables on respondents' energy, macronutrient intake, sodium/potassium ratio, and healthy eating index. Logistic regression was used to assess the impact of socioeconomic status (SES) on diet quality indicators. Age was positively associated with traditional food (TF) consumption and greater energy from protein but negatively associated with total energy and fibre intake. Associations between SES and diet quality differed considerably between men and women and there was considerable regional variability in diet quality measures. Age and cultural variables were significant predictors of diet quality in logistic regression. Increased age and use of the Inuit language in the home were the most significant predictors of TF consumption. Our findings are consistent with studies reporting a nutrition transition in circumpolar Inuit. We found considerable variability in diet quality and complex interaction between SES and cultural variables producing mixed effects that differ by age and gender.

33 CFR 332.1 - Purpose and general considerations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... available and capable of being done after taking into consideration cost, existing technology, and logistics... and the Corps at the national or regional level. No modifications to the basic application, meaning...

Late Holocene Hurricane Activity in the Gulf of Mexico from a Bayou Sediment Archive

NASA Astrophysics Data System (ADS)

Rodysill, J. R.; Donnelly, J. P.; Toomey, M.; Sullivan, R.; MacDonald, D.; Evans, R. L.; Ashton, A. D.

2012-12-01

Hurricanes pose a considerable threat to coastal communities along the Atlantic seaboard and in the Gulf of Mexico. The complex role of ocean and atmospheric dynamics in controlling storm frequency and intensity, and how these relationships could be affected by climate change, remains uncertain. To better predict how storms will impact coastal communities, it is vital to constrain their past behavior, in particular how storm frequency and intensity and the pattern of storm tracks have been influenced by past climate conditions. In an effort to characterize past storm behavior, our work contributes to the growing network of storm records along the Atlantic and Gulf coasts by reconstructing storm-induced deposits in the northern Gulf of Mexico during the Late Holocene. Previous work on the northern Gulf coast has shown considerable centennial-scale variability in the occurrence of intense hurricanes, much like the northern Atlantic coast and in the Caribbean Sea. The timing of active and quiet intervals during the last 1000 years amongst the Gulf Coast records appears to be anti-phased with stormy intervals along the North American east coast. The sparse spatial coverage of the existing intense hurricane reconstructions provides a limited view of the natural variability of intense hurricanes. A new, high resolution reconstruction of storms along the northern Gulf Coast would be beneficial in assembling the picture of the patterns of storminess during the Late Holocene. Our study site, Basin Bayou, is situated on the north side of Choctawhatchee Bay in northwest Florida. From 1851 to 2011, 68 storms have struck the coast within 75 miles of Basin Bayou, of which 10 were Category 3 or greater, making it a prime location to reconstruct intense hurricanes. Basin Bayou openly exchanges water with Choctawhatchee Bay through a narrow channel, which acts as a conduit for propagating storm surges, and potentially coarse-grained bay sediments, into the bayou. Our record is constructed from grain size analyses and core density measurements on multiple cores from Basin Bayou. The upper sediments were dated with 210Pb and 137Cs techniques and compared with the historical record of storms. We observe substantial centennial-scale variability in the occurrence of storm-induced deposits in Basin Bayou over the last 1500 years that aligns considerably well with the temporal distribution of intense storms from preexisting Gulf Coast reconstructions.

Operant Variability: Procedures and Processes

ERIC Educational Resources Information Center

Machado, Armando; Tonneau, Francois

2012-01-01

Barba's (2012) article deftly weaves three main themes in one argument about operant variability. From general theoretical considerations on operant behavior (Catania, 1973), Barba derives methodological guidelines about response differentiation and applies them to the study of operant variability. In the process, he uncovers unnoticed features of…

Autism and peripheral hearing loss: a systematic review.

PubMed

Beers, Alison N; McBoyle, Melanie; Kakande, Emily; Dar Santos, Rachelle C; Kozak, Frederick K

2014-01-01

To systematically review the literature describing the relationship between autism spectrum disorder (ASD) and peripheral hearing loss including literature recommendations for audiological assessment and auditory habilitation in cases where peripheral hearing loss and ASD coexist. Published studies indexed in MEDLINE (1948-2011). The search strategy identified 595 potential studies. After a review of the titles, 115 abstracts were reviewed and 39 articles were retrieved and assessed independently by at least two authors for possible inclusion. 22 articles pertained to children with ASD and peripheral hearing loss, hearing assessment in children with ASD, audiological habilitation for children with ASD or hyper-responsiveness in children with ASD. 17 further studies were garnered from the reference section of the 22 papers. Controversy exists in the literature regarding prevalence of hearing impairment among individuals with ASD. In cases where ASD and hearing impairment co-exist, diagnosis of one condition often leads to a delay in diagnosing the other. Audiological assessment can be difficult in children with ASD and test-retest reliability of behavioural thresholds can be poor. In cases where hearing impairment exists and hearing aids or cochlear implantation are recommended, devices are often fit with special considerations for the child with ASD. Hyper-responsiveness to auditory stimuli may be displayed by individuals with ASD. Evidence or the suspicion of hyper-responsiveness may be taken into consideration when fitting amplification and planning behavioural intervention. Prevalence rates of hearing impairment among individuals with ASD continue to be debated. At present there is no conclusive evidence that children with ASD are at increased risk of peripheral hearing loss. A complete audiological assessment is recommended in all cases where ASD is suspected so as not to delay the diagnosis of hearing impairment in the event that hearing loss and ASD co-exist. Objective assessment measures should be used to confirm behavioural testing in order to ensure reliability of audiological test results. Fitting of hearing aids or cochlear implantation are not contraindicated when hearing loss is present in children with ASD; however, success with these devices can be variable. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Novel models on fluid's variable thermo-physical properties for extensive study on convection heat and mass transfer

NASA Astrophysics Data System (ADS)

Shang, De-Yi; Zhong, Liang-Cai

2017-01-01

Our novel models for fluid's variable physical properties are improved and reported systematically in this work for enhancement of theoretical and practical value on study of convection heat and mass transfer. It consists of three models, namely (1) temperature parameter model, (2) polynomial model, and (3) weighted-sum model, respectively for treatment of temperature-dependent physical properties of gases, temperature-dependent physical properties of liquids, and concentration- and temperature-dependent physical properties of vapour-gas mixture. Two related components are proposed, and involved in each model for fluid's variable physical properties. They are basic physic property equations and theoretical similarity equations on physical property factors. The former, as the foundation of the latter, is based on the typical experimental data and physical analysis. The latter is built up by similarity analysis and mathematical derivation based on the former basic physical properties equations. These models are available for smooth simulation and treatment of fluid's variable physical properties for assurance of theoretical and practical value of study on convection of heat and mass transfer. Especially, so far, there has been lack of available study on heat and mass transfer of film condensation convection of vapour-gas mixture, and the wrong heat transfer results existed in widespread studies on the related research topics, due to ignorance of proper consideration of the concentration- and temperature-dependent physical properties of vapour-gas mixture. For resolving such difficult issues, the present novel physical property models have their special advantages.

Regional variability of farmer decision making and irrigation water use: insights from a data-scarce region of North India

NASA Astrophysics Data System (ADS)

O'Keeffe, Jimmy; Buytaert, Wouter; Brozović, Nick; Mijic, Ana

2014-05-01

Over the last fifty years, changes in agriculture brought about by the Green Revolution have transformed India from a famine-prone, drought-susceptible country into the worlds' third largest grain producer and one of the most intensively irrigated parts of the globe. Regionally, cheap energy, subsidised seeds and fertilisers, and in some areas Government purchase guarantees for grain promote the intensification of farming. While this allows farmers to survive, it also aggravates the drain agriculture is having on resources, particularly energy and water. Analysis at a regional scale, however, masks the considerable spatial variability that exists on a more localised level and must be taken into consideration to understand correctly aggregate system response to policy, hydrologic, and climatic change. In this study we present and analyse the results from over 100 farmer interviews conducted in the data-scarce districts of Jalaun and Sitapur on the Gangetic Plains of Uttar Pradesh during the post monsoon period of 2013. Variables such as the volumes and timing of irrigation water applied, sources of water, methods of abstraction and irrigation, and costs incurred are mapped, using qualitative data analysis and GIS. Large differences between the districts emerge, for instance in the region of Jalaun where cheaper canal water is available in addition to groundwater. This has enabled farmers to afford more water efficient technologies such as sprinklers, a practice not found in Sitapur which depends almost exclusively on more expensive diesel pumps. Results are used to delineate the spatial variability in water use practices, along with farmer behaviour and decision making. The primary data are compared with socio-economic information taken from regionally produced statistical abstracts. The combined data are used to identify the main drivers that influence farmer decision-making, which is in turn leading to groundwater overdraught in many parts of North India. Finally, the importance of understanding and modelling farmer behaviour for policy development, and the significance of this in the face of growing population, changes in socio-economic conditions, and climate change are discussed. Taking these variables into account is necessary in creating a transparent, socially acceptable and economically viable balance between sustainable water resources and farmer livelihoods.

Short-term favorable weather conditions are an important control of interannual variability in carbon and water fluxes

Treesearch

Jakob Zscheischler; Simone Fatichi; Sebastian Wolf; Peter D. Blanken; Gil Bohrer; Ken Clark; Ankur R. Desai; David Hollinger; Trevor Keenan; Kimberly A. Novick; Sonia I. Seneviratne

2016-01-01

Ecosystem models often perform poorly in reproducing interannual variability in carbon and water fluxes, resulting in considerable uncertainty when estimating the land-carbon sink. While many aggregated variables (growing season length, seasonal precipitation, or temperature) have been suggested as predictors for interannual variability in carbon fluxes, their...

Nocebo and the potential harm of 'high risk' labelling: a scoping review.

PubMed

Symon, Andrew; Williams, Brian; Adelasoye, Qadir A; Cheyne, Helen

2015-07-01

A discussion of the existence, prevalence and characteristics of the nocebo effect in health care. There is increasing but inconsistent evidence for nocebo effects (the opposite of placebo). Causal mechanisms are believed to be similar to placebo (negative effects result from suggestions of negative clinical outcomes). Risk screening in health care may produce this unintended effect through labelling some patients as high risk. Given health care's almost universal coverage this potentially affects many people. Discussion paper following a scoping review of the existence and frequency of nocebo. Literature databases (PsycINFO, MEDLINE, CCTR, CINAHL and EMBASE) searched from inception dates to 2013. Significant empirical evidence indicates that negative beliefs may impact on health outcomes (incidence estimates range from 3-27%). The nocebo effect, rooted in the complex interplay between physiological functioning and social factors, appears significantly more common among women and where prior negative knowledge or expectations exist. Pre-existing psychological characteristics (anxiety, neuroses, panic disorder or pessimism) exacerbate it. While the placebo effect is well documented, there has been no systematic attempt to synthesize primary empirical research on the role of nocebo. It is possible that nocebo outcomes may be preventable through careful consideration of information provision and the prior identification of potentially high risk individuals. This paper summarizes the scale and importance of the nocebo effect, its distribution according to a range of social and clinical variables and its known relation to psychological precursors. It identifies important gaps in the research literature. © 2015 John Wiley & Sons Ltd.

Feasibility of a 30-meter space based laser transmitter

NASA Technical Reports Server (NTRS)

Berggren, R. R.; Lenertz, G. E.

1975-01-01

A study was made of the application of large expandable mirror structures in future space missions to establish the feasibility and define the potential of high power laser systems for such applications as propulsion and power transmission. Application of these concepts requires a 30-meter diameter, diffraction limited mirror for transmission of the laser energy. Three concepts for the transmitter are presented. These concepts include consideration of continuous as well as segmented mirror surfaces and the major stow-deployment categories of inflatable, variable geometry and assembled-in-space structures. The mirror surface for each concept would be actively monitored and controlled to maintain diffraction limited performance at 10.6 microns during operation. The proposed mirror configurations are based on existing aerospace state-of-the-art technology. The assembled-in-space concept appears to be the most feasible, at this time.

Genetic Diversity in the Paramecium aurelia Species Complex

PubMed Central

Catania, Francesco; Wurmser, François; Potekhin, Alexey A.; Przyboś, Ewa; Lynch, Michael

2009-01-01

Current understanding of the population genetics of free-living unicellular eukaryotes is limited, and the amount of genetic variability in these organisms is still a matter of debate. We characterized—reproductively and genetically—worldwide samples of multiple Paramecium species belonging to a cryptic species complex, Paramecium aurelia, whose species have been shown to be reproductively isolated. We found that levels of genetic diversity both in the nucleus and in the mitochondrion are substantial within groups of reproductively compatible P. aurelia strains but drop considerably when strains are partitioned according to their phylogenetic groupings. Our study reveals the existence of discrepancies between the mating behavior of a number of P. aurelia strains and their multilocus genetic profile, a controversial finding that has major consequences for both the current methods of species assignment and the species problem in the P. aurelia complex. PMID:19023087

The Pr 2O 3/Si(0 0 1) interface studied by synchrotron radiation photo-electron spectroscopy

NASA Astrophysics Data System (ADS)

Schmeißer, D.; Müssig, H.-J.

2003-10-01

Pr 2O 3 is currently under consideration as a potential replacement for SiO 2 as the gate-dielectric material for sub-0.1 μm complementary metal-oxide-semiconductor (CMOS) technology. We studied the Pr 2O 3/Si(0 0 1) interface by a non-destructive depth profiling using synchrotron radiation photoelectron spectroscopy. Our data suggests that there is no silicide formation at the interface. Based on reported results, a chemical reactive interface exists, consisting of a mixed Si-Pr oxide such as (Pr 2O 3) x(SiO 2) 1- x, i.e. as a silicate phase with variable silicon content. This pseudo-binary alloy at the interface offers large flexibility toward successful integration of Pr 2O 3 into future CMOS technologies.

Set of Comparable Carbon Footprints for Highway Travel in Metropolitan America

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

Southworth, Frank; Sonnenberg, Anthon

2011-01-01

The authors describe the development of a set of carbon dioxide emissions estimates for highway travel by automobile, truck, bus and other public transit vehicle movements within the nation s 100 largest metropolitan areas, in calendar year 2005. Considerable variability is found to exist across metropolitan areas when these greenhouse gas emissions are measured on a per capita and a per gross metropolitan product (GMP) basis. Least square regression modeling shows a relationship between emissions per capita and per GMP with truck traffic share, transit share, employment density, population dispersion within the metro area, and GMP per capita. As amore » result many of the nation s largest metropolitan areas tend to have lower CO2 emissions per capita and per GMP than smaller and more recently developed metro areas.« less

Experience Modulates the Reproductive Response to Heat Stress in C. elegans via Multiple Physiological Processes

PubMed Central

Gouvêa, Devin Y.; Aprison, Erin Z.; Ruvinsky, Ilya

2015-01-01

Natural environments are considerably more variable than laboratory settings and often involve transient exposure to stressful conditions. To fully understand how organisms have evolved to respond to any given stress, prior experience must therefore be considered. We investigated the effects of individual and ancestral experience on C. elegans reproduction. We documented ways in which cultivation at 15°C or 25°C affects developmental time, lifetime fecundity, and reproductive performance after severe heat stress that exceeds the fertile range of the organism but is compatible with survival and future fecundity. We found that experience modulates multiple aspects of reproductive physiology, including the male and female germ lines and the interaction between them. These responses vary in their environmental sensitivity, suggesting the existence of complex mechanisms for coping with unpredictable and stressful environments. PMID:26713620

Guidelines for human epidermal growth factor receptor 2 testing: biologic and methodologic considerations.

PubMed

Sauter, Guido; Lee, James; Bartlett, John M S; Slamon, Dennis J; Press, Michael F

2009-03-10

The goal of this review is to systematically address a number of issues raised in the American Society of Clinical Oncology-College of American Pathologists (ASCO-CAP) guidelines on testing for the human epidermal growth factor receptor 2 (HER-2) alteration. A group of investigators who are experienced in the conduct and interpretation of HER-2 assay methods reviewed the ASCO-CAP guidelines and address several areas of the HER-2 testing guidelines with a particular emphasis on biologic and methodologic considerations. Although HER-2 status determined by immunohistochemistry (IHC) and the status determined by fluorescent in situ hybridization (FISH) are significantly correlated, we feel that standard considerations of laboratory testing, including test accuracy, reproducibility, and precision, as well as the current data favor FISH over IHC assay methods for determining HER-2 status. These considerations are clearly important in clinical practice because HER2 amplification is directly linked to protein expression levels in breast cancer. However, this protein is not consistently analyzed in formalin-fixed tissues as a result of variability in fixation methods and times and the impact of fixation on HER-2 protein antigenicity. Conversely, gene amplification and FISH are significantly less dependent on tissue fixation methods, making this assay more reproducible between central and peripheral laboratories than IHC. Moreover, review of the existing data demonstrate that FISH is more strongly correlated with responsiveness to either trastuzumab or lapatinib treatment. Until other methods achieve similar test accuracy, reproducibility, and predictive value, we suggest FISH as the primary HER-2 testing modality for women with breast cancer who are candidates for HER-2-targeted therapies.

Variables Related to Romanticism and Self-Esteem in Pregnant Teenagers.

ERIC Educational Resources Information Center

Medora, Nilufer P.; And Others

1993-01-01

Administered Dean Romanticism Scale and Bachman Self-Esteem Scale to 121 pregnant adolescents (ages 12-21). Found that two variables were significantly related to feelings of romanticism: adoption considerations and whether adolescent planned to have child with the baby's father. Two variables were significantly related to self-esteem: incidence…

Decadal variability of the Tropical Atlantic Ocean Surface Temperature in shipboard measurements and in a Global Ocean-Atmosphere model

NASA Technical Reports Server (NTRS)

Mehta, Vikram M.; Delworth, Thomas

1995-01-01

Sea surface temperature (SST) variability was investigated in a 200-yr integration of a global model of the coupled oceanic and atmospheric general circulations developed at the Geophysical Fluid Dynamics Laboratory (GFDL). The second 100 yr of SST in the coupled model's tropical Atlantic region were analyzed with a variety of techniques. Analyses of SST time series, averaged over approximately the same subregions as the Global Ocean Surface Temperature Atlas (GOSTA) time series, showed that the GFDL SST anomalies also undergo pronounced quasi-oscillatory decadal and multidecadal variability but at somewhat shorter timescales than the GOSTA SST anomalies. Further analyses of the horizontal structures of the decadal timescale variability in the GFDL coupled model showed the existence of two types of variability in general agreement with results of the GOSTA SST time series analyses. One type, characterized by timescales between 8 and 11 yr, has high spatial coherence within each hemisphere but not between the two hemispheres of the tropical Atlantic. A second type, characterized by timescales between 12 and 20 yr, has high spatial coherence between the two hemispheres. The second type of variability is considerably weaker than the first. As in the GOSTA time series, the multidecadal variability in the GFDL SST time series has approximately opposite phases between the tropical North and South Atlantic Oceans. Empirical orthogonal function analyses of the tropical Atlantic SST anomalies revealed a north-south bipolar pattern as the dominant pattern of decadal variability. It is suggested that the bipolar pattern can be interpreted as decadal variability of the interhemispheric gradient of SST anomalies. The decadal and multidecadal timescale variability of the tropical Atlantic SST, both in the actual and in the GFDL model, stands out significantly above the background 'red noise' and is coherent within each of the time series, suggesting that specific sets of processes may be responsible for the choice of the decadal and multidecadal timescales. Finally, it must be emphasized that the GFDL coupled ocean-atmosphere model generates the decadal and multidecadal timescale variability without any externally applied force, solar or lunar, at those timescales.

Modelling the co-evolution of indirect genetic effects and inherited variability.

PubMed

Marjanovic, Jovana; Mulder, Han A; Rönnegård, Lars; Bijma, Piter

2018-03-28

When individuals interact, their phenotypes may be affected not only by their own genes but also by genes in their social partners. This phenomenon is known as Indirect Genetic Effects (IGEs). In aquaculture species and some plants, however, competition not only affects trait levels of individuals, but also inflates variability of trait values among individuals. In the field of quantitative genetics, the variability of trait values has been studied as a quantitative trait in itself, and is often referred to as inherited variability. Such studies, however, consider only the genetic effect of the focal individual on trait variability and do not make a connection to competition. Although the observed phenotypic relationship between competition and variability suggests an underlying genetic relationship, the current quantitative genetic models of IGE and inherited variability do not allow for such a relationship. The lack of quantitative genetic models that connect IGEs to inherited variability limits our understanding of the potential of variability to respond to selection, both in nature and agriculture. Models of trait levels, for example, show that IGEs may considerably change heritable variation in trait values. Currently, we lack the tools to investigate whether this result extends to variability of trait values. Here we present a model that integrates IGEs and inherited variability. In this model, the target phenotype, say growth rate, is a function of the genetic and environmental effects of the focal individual and of the difference in trait value between the social partner and the focal individual, multiplied by a regression coefficient. The regression coefficient is a genetic trait, which is a measure of cooperation; a negative value indicates competition, a positive value cooperation, and an increasing value due to selection indicates the evolution of cooperation. In contrast to the existing quantitative genetic models, our model allows for co-evolution of IGEs and variability, as the regression coefficient can respond to selection. Our simulations show that the model results in increased variability of body weight with increasing competition. When competition decreases, i.e., cooperation evolves, variability becomes significantly smaller. Hence, our model facilitates quantitative genetic studies on the relationship between IGEs and inherited variability. Moreover, our findings suggest that we may have been overlooking an entire level of genetic variation in variability, the one due to IGEs.

Concept considerations for a small orbital transfer vehicle

NASA Technical Reports Server (NTRS)

Green, M.; Sibila, A. I.

1979-01-01

This paper summarizes a study of small orbital transfer vehicles to place payloads in orbits with altitudes above those of the standard Shuttle operations. The overall objective of the study is to examine the role of the small orbital transfer vehicle (SOTV) in Shuttle operations and to identify typical propulsion concepts for accomplishing the mission. Consideration is given to existing and planned systems and upper stages, along with new propulsion stages. The new propulsion concept development examines tandem and clustered solids, controlled solids, monopropellant and bipropellant liquids, and staged solid/liquid combinations. The paper presents considerations of the mission requirements, tradeoffs of the various configurations, and candidate selections. For the selected candidate concepts the performance, support equipment, operational considerations and program costs were determined. The results show that a new modular liquid stage system is cost effective in handling the majority of the payloads considered. The remainder of the payloads can be accomodated by existing systems.

What matters after sleeve gastrectomy: patient characteristics or surgical technique?

PubMed

Dhar, Vikrom K; Hanseman, Dennis J; Watkins, Brad M; Paquette, Ian M; Shah, Shimul A; Thompson, Jonathan R

2018-03-01

The impact of operative technique on outcomes in laparoscopic sleeve gastrectomy has been explored previously; however, the relative importance of patient characteristics remains unknown. Our aim was to characterize national variability in operative technique for laparoscopic sleeve gastrectomy and determine whether patient-specific factors are more critical to predicting outcomes. We queried the database of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program for laparoscopic sleeve gastrostomies performed in 2015 (n = 88,845). Logistic regression models were used to determine predictors of postoperative outcomes. In 2015, >460 variations of laparoscopic sleeve gastrectomy were performed based on combinations of bougie size, distance from the pylorus, use of staple line reinforcement, and oversewing of the staple line. Despite such substantial variability, technique variants were not predictive of outcomes, including perioperative morbidity, leak, or bleeding (all P ≥ .05). Instead, preoperative patient characteristics were found to be more predictive of these outcomes after laparoscopic sleeve gastrectomy. Only history of gastroesophageal disease (odds ratio 1.44, 95% confidence interval 1.08-1.91, P < .01) was associated with leak. Considerable variability exists in technique among surgeons nationally, but patient characteristics are more predictive of adverse outcomes after laparoscopic sleeve gastrectomy. Bundled payments and reimbursement policies should account for patient-specific factors in addition to current accreditation and volume thresholds when deciding risk-adjustment strategies. Copyright © 2018 Elsevier Inc. All rights reserved.

Methodological uncertainty in quantitative prediction of human hepatic clearance from in vitro experimental systems.

PubMed

Hallifax, D; Houston, J B

2009-03-01

Mechanistic prediction of unbound drug clearance from human hepatic microsomes and hepatocytes correlates with in vivo clearance but is both systematically low (10 - 20 % of in vivo clearance) and highly variable, based on detailed assessments of published studies. Metabolic capacity (Vmax) of commercially available human hepatic microsomes and cryopreserved hepatocytes is log-normally distributed within wide (30 - 150-fold) ranges; Km is also log-normally distributed and effectively independent of Vmax, implying considerable variability in intrinsic clearance. Despite wide overlap, average capacity is 2 - 20-fold (dependent on P450 enzyme) greater in microsomes than hepatocytes, when both are normalised (scaled to whole liver). The in vitro ranges contrast with relatively narrow ranges of clearance among clinical studies. The high in vitro variation probably reflects unresolved phenotypical variability among liver donors and practicalities in processing of human liver into in vitro systems. A significant contribution from the latter is supported by evidence of low reproducibility (several fold) of activity in cryopreserved hepatocytes and microsomes prepared from the same cells, between separate occasions of thawing of cells from the same liver. The large uncertainty which exists in human hepatic in vitro systems appears to dominate the overall uncertainty of in vitro-in vivo extrapolation, including uncertainties within scaling, modelling and drug dependent effects. As such, any notion of quantitative prediction of clearance appears severely challenged.

Ergonomics: The Forgotten Variable.

ERIC Educational Resources Information Center

Fitterman, L. Jeffrey

This paper describes ergonomics and the need to adapt worksites and technologies for individuals with physical or sensory disabilities. It provides suggestions for how to design an appropriate setup, design considerations, environmental considerations, chairs, monitor height, ambient noise, light, and electricity. Recommendations include: (1)…

Size and burden of mental disorders in Europe--a critical review and appraisal of 27 studies.

PubMed

Wittchen, Hans-Ulrich; Jacobi, Frank

2005-08-01

Epidemiological data on a wide range of mental disorders from community studies conducted in European countries are presented to determine the availability and consistency of prevalence, disability and treatment findings for the EU. Using a stepwise multimethod approach, 27 eligible studies with quite variable designs and methods including over 150,000 subjects from 16 European countries were identified. Prevalence: On the basis of meta-analytic techniques as well as on reanalyses of selected data sets, it is estimated that about 27% (equals 82.7 million; 95% CI: 78.5-87.1) of the adult EU population, 18-65 of age, is or has been affected by at least one mental disorder in the past 12 months. Taking into account the considerable degree of comorbidity (about one third had more than one disorder), the most frequent disorders are anxiety disorders, depressive, somatoform and substance dependence disorders. When taking into account design, sampling and other methodological differences between studies, little evidence seems to exist for considerable cultural or country variation. Disability and treatment: despite very divergent and fairly crude assessment strategies, the available data consistently demonstrate (a) an association of all mental disorders with a considerable disability burden in terms of number of work days lost (WLD) and (b) generally low utilization and treatment rates. Only 26% of all cases had any consultation with professional health care services, a finding suggesting a considerable degree of unmet need. The paper highlights considerable future research needs for coordinated EU studies across all disorders and age groups. As prevalence estimates could not simply be equated with defined treatment needs, such studies should determine the degree of met and unmet needs for services by taking into account severity, disability and comorbidity. These needs are most pronounced for the new EU member states as well as more generally for adolescent and older populations.

Micro-evolution due to pollution: possible consequences for ecosystem responses to toxic stress.

PubMed

Medina, Matías H; Correa, Juan A; Barata, Carlos

2007-05-01

Polluting events can change community structure and ecosystem functioning. Selection of genetically inherited tolerance on exposed populations, here referred as micro-evolution due to pollution, has been recognized as one of the causes of these changes. However, there is a gap between studies addressing this process and those assessing effects at higher levels of biological organization. In this review we attempt to address these evolutionary considerations into the ecological risk assessment (ERA) of polluting events and to trigger the discussion about the consequences of this process for the ecosystem response to toxic stress. We provide clear evidence that pollution drives micro-evolutionary processes in several species. When this process occurs, populations inhabiting environments that become polluted may persist. However, due to the existence of ecological costs derived from the loss of genetic variability, negative pleiotropy with fitness traits and/or from physiological alterations, micro-evolution due to pollution may alter different properties of the affected populations. Despite the existence of empirical evidence showing that safety margins currently applied in the ERA process may account for pollution-induced genetic changes in tolerance, information regarding long-term ecological consequences at higher levels of biological organization due to ecological costs is not explicitly considered in these procedures. In relation to this, we present four testable hypotheses considering that micro-evolution due to pollution acts upon the variability of functional response traits of the exposed populations and generates changes on their functional effect traits, therefore, modifying the way species exploit their ecological niches and participate in the overall ecosystem functioning.

Screening variability and change of soil moisture under wide-ranging climate conditions: Snow dynamics effects.

PubMed

Verrot, Lucile; Destouni, Georgia

2015-01-01

Soil moisture influences and is influenced by water, climate, and ecosystem conditions, affecting associated ecosystem services in the landscape. This paper couples snow storage-melting dynamics with an analytical modeling approach to screening basin-scale, long-term soil moisture variability and change in a changing climate. This coupling enables assessment of both spatial differences and temporal changes across a wide range of hydro-climatic conditions. Model application is exemplified for two major Swedish hydrological basins, Norrström and Piteälven. These are located along a steep temperature gradient and have experienced different hydro-climatic changes over the time period of study, 1950-2009. Spatially, average intra-annual variability of soil moisture differs considerably between the basins due to their temperature-related differences in snow dynamics. With regard to temporal change, the long-term average state and intra-annual variability of soil moisture have not changed much, while inter-annual variability has changed considerably in response to hydro-climatic changes experienced so far in each basin.

Highly variable aerodynamic roughness length (z0) for a hummocky debris-covered glacier

NASA Astrophysics Data System (ADS)

Miles, Evan S.; Steiner, Jakob F.; Brun, Fanny

2017-08-01

The aerodynamic roughness length (z0) is an essential parameter in surface energy balance studies, but few literature values exist for debris-covered glaciers. We use microtopographic and aerodynamic methods to assess the spatial variability of z0 for Lirung Glacier, Nepal. We apply structure from motion to produce digital elevation models for three nested domains: five 1 m2 plots, a 21,300 m2 surface depression, and the lower 550,000 m2 of the debris-mantled tongue. Wind and temperature sensor towers were installed in the vicinity of the plots within the surface depression in October 2014. We calculate z0 according to a variety of transect-based microtopographic parameterizations for each plot, then develop a grid version of the algorithms by aggregating data from all transects. This grid approach is applied to the surface depression digital elevation model to characterize z0 spatial variability. The algorithms reproduce the same variability among transects and plots, but z0 estimates vary by an order of magnitude between algorithms. Across the study depression, results from different algorithms are strongly correlated. Using Monin-Obukov similarity theory, we derive z0 values from the meteorological data. Using different stability criteria, we derive median values of z0 between 0.03 m and 0.05 m, but with considerable uncertainty due to the glacier's complex topography. Considering estimates from these algorithms, results suggest that z0 varies across Lirung Glacier between ˜0.005 m (gravels) to ˜0.5 m (boulders). Future efforts should assess the importance of such variable z0 values in a distributed energy balance model.

Managing living marine resources in a dynamic environment: The role of seasonal to decadal climate forecasts

NASA Astrophysics Data System (ADS)

Tommasi, Desiree; Stock, Charles A.; Hobday, Alistair J.; Methot, Rick; Kaplan, Isaac C.; Eveson, J. Paige; Holsman, Kirstin; Miller, Timothy J.; Gaichas, Sarah; Gehlen, Marion; Pershing, Andrew; Vecchi, Gabriel A.; Msadek, Rym; Delworth, Tom; Eakin, C. Mark; Haltuch, Melissa A.; Séférian, Roland; Spillman, Claire M.; Hartog, Jason R.; Siedlecki, Samantha; Samhouri, Jameal F.; Muhling, Barbara; Asch, Rebecca G.; Pinsky, Malin L.; Saba, Vincent S.; Kapnick, Sarah B.; Gaitan, Carlos F.; Rykaczewski, Ryan R.; Alexander, Michael A.; Xue, Yan; Pegion, Kathleen V.; Lynch, Patrick; Payne, Mark R.; Kristiansen, Trond; Lehodey, Patrick; Werner, Francisco E.

2017-03-01

Recent developments in global dynamical climate prediction systems have allowed for skillful predictions of climate variables relevant to living marine resources (LMRs) at a scale useful to understanding and managing LMRs. Such predictions present opportunities for improved LMR management and industry operations, as well as new research avenues in fisheries science. LMRs respond to climate variability via changes in physiology and behavior. For species and systems where climate-fisheries links are well established, forecasted LMR responses can lead to anticipatory and more effective decisions, benefitting both managers and stakeholders. Here, we provide an overview of climate prediction systems and advances in seasonal to decadal prediction of marine-resource relevant environmental variables. We then describe a range of climate-sensitive LMR decisions that can be taken at lead-times of months to decades, before highlighting a range of pioneering case studies using climate predictions to inform LMR decisions. The success of these case studies suggests that many additional applications are possible. Progress, however, is limited by observational and modeling challenges. Priority developments include strengthening of the mechanistic linkages between climate and marine resource responses, development of LMR models able to explicitly represent such responses, integration of climate driven LMR dynamics in the multi-driver context within which marine resources exist, and improved prediction of ecosystem-relevant variables at the fine regional scales at which most marine resource decisions are made. While there are fundamental limits to predictability, continued advances in these areas have considerable potential to make LMR managers and industry decision more resilient to climate variability and help sustain valuable resources. Concerted dialog between scientists, LMR managers and industry is essential to realizing this potential.

To pair or not to pair: Sources of social variability with white-faced saki monkeys (Pithecia pithecia) as a case study.

PubMed

Thompson, Cynthia L

2016-05-01

Intraspecific variability in social systems is gaining increased recognition in primatology. Many primate species display variability in pair-living social organizations through incorporating extra adults into the group. While numerous models exist to explain primate pair-living, our tools to assess how and why variation in this trait occurs are currently limited. Here I outline an approach which: (i) utilizes conceptual models to identify the selective forces driving pair-living; (ii) outlines novel possible causes for variability in social organization; and (iii) conducts a holistic species-level analysis of social behavior to determine the factors contributing to variation in pair-living. A case study on white-faced sakis (Pithecia pithecia) is used to exemplify this approach. This species lives in either male-female pairs or groups incorporating "extra" adult males and/or females. Various conceptual models of pair-living suggest that high same-sex aggression toward extra-group individuals is a key component of the white-faced saki social system. Variable pair-living in white-faced sakis likely represents alternative strategies to achieve competency in this competition, in which animals experience conflicting selection pressures between achieving successful group defense and maintaining sole reproductive access to mates. Additionally, independent decisions by individuals may generate social variation by preventing other animals from adopting a social organization that maximizes fitness. White-faced saki inter-individual relationships and demographic patterns also lend conciliatory support to this conclusion. By utilizing both model-level and species-level approaches, with a consideration for potential sources of variation, researchers can gain insight into the factors generating variation in pair-living social organizations. © 2014 The Authors. American Journal of Primatology published by Wiley Periodicals, Inc.

Efficient identification of context dependent subgroups of risk from genome wide association studies

PubMed Central

Dyson, Greg; Sing, Charles F.

2014-01-01

We have developed a modified Patient Rule-Induction Method (PRIM) as an alternative strategy for analyzing representative samples of non-experimental human data to estimate and test the role of genomic variations as predictors of disease risk in etiologically heterogeneous sub-samples. A computational limit of the proposed strategy is encountered when the number of genomic variations (predictor variables) under study is large (> 500) because permutations are used to generate a null distribution to test the significance of a term (defined by values of particular variables) that characterizes a sub-sample of individuals through the peeling and pasting processes. As an alternative, in this paper we introduce a theoretical strategy that facilitates the quick calculation of Type I and Type II errors in the evaluation of terms in the peeling and pasting processes carried out in the execution of a PRIM analysis that are underestimated and non-existent, respectively, when a permutation-based hypothesis test is employed. The resultant savings in computational time makes possible the consideration of larger numbers of genomic variations (an example genome wide association study is given) in the selection of statistically significant terms in the formulation of PRIM prediction models. PMID:24570412

Towards large-cohort comparative studies to define the factors influencing the gut microbial community structure of ASD patients

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

McDonald, Daniel; Hornig, Mady; Lozupone, Catherine

Differences in the gut microbiota have been reported between individuals with autism spectrum disorders (ASD) and neurotypical controls, although direct evidence that changes in the microbiome contribute to causing ASD has been scarce to date. Here we summarize some considerations of experimental design that can help untangle causality in this complex system. In particular, large cross-sectional studies that can factor out important variables such as diet, prospective longitudinal studies that remove some of the influence of interpersonal variation in the microbiome (which is generally high, especially in children), and studies transferring microbial communities into germ-free mice may be especially useful.more » Controlling for the effects of technical variables, which have complicated efforts to combine existing studies, is critical when biological effect sizes are small. Large citizen-science studies with thousands of participants such as the American Gut Project have been effective at uncovering subtle microbiome effects in self-collected samples and with self-reported diet and behavior data, and may provide a useful complement to other types of traditionally funded and conducted studies in the case of ASD, especially in the hypothesis generation phase.« less

Variability of hydrologic regimes and morphology in constructed open-ditch channels

USGS Publications Warehouse

Strock, J.S.; Magner, J.A.; Richardson, W.B.; Sadowsky, M.J.; Sands, G.R.; Venterea, R.T.; ,

2004-01-01

Open-ditch ecosystems are potential transporters of considerable loads of nutrients, sediment, pathogens and pesticides from direct inflow from agricultural land to small streams and larger rivers. Our objective was to compare hydrology and channel morphology between two experimental open-ditch channels. An open-ditch research facility incorporating a paired design was constructed during 2002 near Lamberton, MN. A200-m reach of existing drainage channel was converted into a system of four parallel channels. The facility was equipped with water level control devices and instrumentation for flow monitoring and water sample collection on upstream and downstream ends of the system. Hydrographs from simulated flow during year one indicated that paired open-ditch channels responded similarly to changes in inflow. Variability in hydrologic response between open-ditches was attributed to differences in open-ditch channel bottom elevation and vegetation density. No chemical, biological, or atmospheric measurements were made during 2003. Potential future benefits of this research include improved biological diversity and integrity of open-ditch ecosystems, reduce flood peaks and increased flow during critical low-flow periods, improved and more efficient nitrogen retention within the open-ditch ecosystem, and decreased maintenance cost associated with reduced frequency of open-ditch maintenance.

Review of the tactical evaluation tools for youth players, assessing the tactics in team sports: football.

PubMed

González-Víllora, Sixto; Serra-Olivares, Jaime; Pastor-Vicedo, Juan Carlos; da Costa, Israel Teoldo

2015-01-01

For sports assessment to be comprehensive, it must address all variables of sports development, such as psychological, social-emotional, physical and physiological, technical and tactical. Tactical assessment has been a neglected variable until the 1980s or 1990s. In the last two decades (1995-2015), the evolution of tactical assessment has grown considerably, given its importance in game performance. The aim of this paper is to compile and analyze different tactical measuring tools in team sports, particularly in soccer, through a bibliographical review. Six tools have been selected on five different criteria: (1) Instruments which assess tactics, (2) The studies have an evolution approach related to the tactical principles, (3) With a valid and reliable method, (4) The existence of publications mentioning the tool in the method, v. Applicable in different sports contexts. All six tools are structured around seven headings: introduction, objective(s), tactical principles, materials, procedures, instructions/rules of the game and published studies. In conclusion, the teaching-learning processes more tactical oriented have useful tactical assessment instrument in the literature. The selection of one or another depends some context information, like age and level of expertise of the players.

ELISA microarray technology as a high-throughput system for cancer biomarker validation

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

Zangar, Richard C.; Daly, Don S.; White, Amanda M.

A large gap currently exists between the ability to discover potential biomarkers and the ability to assess the real value of these proteins for cancer screening. One major challenge in biomarker validation is the inherent variability in biomarker levels. This variability stems from the diversity across the human population and the considerable molecular heterogeneity between individual tumors, even those that originate from a single tissue. Another major challenge with cancer screening is that most cancers are rare in the general population, meaning that the specificity of an assay must be very high if the number of false positive is notmore » going to be much greater than the number of true positives. Because of these challenges with biomarker validation, it is necessary to analysis of thousands of samples before a clear idea of the utility of a screening assay can be determined. Enzyme-linked immunosorbent assay (ELISA) microarray technology can simultaneously quantify levels of multiple proteins and has the potential to accelerate biomarker validation. In this review, we discuss current ELISA microarray technology and the enabling advances needed to achieve the reproducibility and throughput that are required to evaluate cancer biomarkers.« less

Semi-Quantitative Evaluation of Secondary Carbonates via Portable X-ray Fluorescence Spectrometry

NASA Astrophysics Data System (ADS)

Chakraborty, Somsubhra; Weindorf, David; Weindorf, Camille; Duda, Bogdan; Pennington, Sarah; Ortiz, Rebekah

2017-04-01

Secondary calcium carbonate commonly occurs in subsoils of semi-arid soils worldwide. In US Soil Taxonomy, such horizons are frequently described as Bk, Bkk, Bkm, Bkkm, or Ck horizons at variable stages of development. Specifically, the Soil Survey Staff uses a qualitative scale of one through six to indicate differential developmental stages. However, considerable disagreement exists even among experienced soil scientists. Evaluating 75 soil samples from across four US states, a portable X-ray fluorescence (PXRF) spectrometer was used to quantify the total soil Ca content and compare it to average developmental stage scores as determined by a panel of Soil Survey Staff personnel. Samples were evaluated both as intact aggregates as well as ground (<2 mm), homogenized powders. PXRF readings of total soil Ca concentration steadily increased under both conditions as developmental stage progressed. However, minimal difference was observed between stage five and six carbonate accumulation. Stage three showed the widest variability in total soil Ca. Given than PXRF cannot distinguish between primary and secondary CaCO3 in soils, interpretation by the analyst remains essential. Nonetheless, PXRF provides an important tool for assessing carbonate laden subsoils providing elemental differentiation beyond that perceived by the human eye.

Towards large-cohort comparative studies to define the factors influencing the gut microbial community structure of ASD patients

DOE PAGES

McDonald, Daniel; Hornig, Mady; Lozupone, Catherine; ...

2015-03-09

Differences in the gut microbiota have been reported between individuals with autism spectrum disorders (ASD) and neurotypical controls, although direct evidence that changes in the microbiome contribute to causing ASD has been scarce to date. Here we summarize some considerations of experimental design that can help untangle causality in this complex system. In particular, large cross-sectional studies that can factor out important variables such as diet, prospective longitudinal studies that remove some of the influence of interpersonal variation in the microbiome (which is generally high, especially in children), and studies transferring microbial communities into germ-free mice may be especially useful.more » Controlling for the effects of technical variables, which have complicated efforts to combine existing studies, is critical when biological effect sizes are small. Large citizen-science studies with thousands of participants such as the American Gut Project have been effective at uncovering subtle microbiome effects in self-collected samples and with self-reported diet and behavior data, and may provide a useful complement to other types of traditionally funded and conducted studies in the case of ASD, especially in the hypothesis generation phase.« less

The Potential for Differential Findings among Invariance Testing Strategies for Multisample Measured Variable Path Models

ERIC Educational Resources Information Center

Mann, Heather M.; Rutstein, Daisy W.; Hancock, Gregory R.

2009-01-01

Multisample measured variable path analysis is used to test whether causal/structural relations among measured variables differ across populations. Several invariance testing approaches are available for assessing cross-group equality of such relations, but the associated test statistics may vary considerably across methods. This study is a…

Study of Integration Considerations for Wireless Emergency Alerts

DTIC Science & Technology

2014-02-01

affect adoption. Section 4 presents a list of overall considerations for integrating a WEA messaging solution into an existing emergency management...in a product may negatively affect another de- sired quality. This section offers considerations for balancing an organization’s priorities con... affect what emergency management agencies can, should, and must do with respect to conducting exercises and issuing alerts. More information about

Attitudes and approaches for withdrawing drugs for children with clinically inactive non-systemic JIA: a survey of the Childhood Arthritis and Rheumatology Research Alliance

PubMed Central

Horton, Daniel B.; Onel, Karen B.; Beukelman, Timothy; Ringold, Sarah

2016-01-01

Objective To assess the attitudes and strategies of pediatric rheumatology clinicians towards withdrawing medications for children with clinically inactive juvenile idiopathic arthritis (JIA). Methods Members of the Childhood Arthritis and Rheumatology Research Alliance (CARRA) completed an anonymous electronic survey on decision-making and approaches for withdrawing medications for inactive non-systemic JIA. Data were analyzed using descriptive statistics. Results Of 388 clinicians in CARRA, 124 completed surveys (32%), predominantly attending pediatric rheumatologists. The most highly ranked factors in decision-making for withdrawing medications were duration of clinical inactivity, drug toxicity, duration of prior activity, patient/family preferences, joint damage, and JIA category. Diagnoses of RF-positive polyarthritis and persistent oligoarthritis made respondents less likely and more likely, respectively, to withdraw JIA medications. Three-quarters of respondents waited for 6–12 months of inactive disease before stopping methotrexate or biologics, but preferences varied. There was also considerable variability in the strategies used to reduce, taper, or stop medications for clinically inactive JIA; most commonly, clinicians reported slow medication tapers lasting at least 2 months. For children on combination methotrexate-biologic therapy, 63% of respondents preferred stopping methotrexate first. Most clinicians reported using imaging only seldom or sometimes to guide decision-making, but most were also reluctant to withdraw medications in the presence of asymptomatic imaging abnormalities suggestive of subclinical inflammation. Conclusion Considerable variability exists among pediatric rheumatology clinicians regarding when and how to withdraw medications for children with clinically inactive JIA. More research is needed to identify the most effective approaches to withdraw medications and predictors of outcomes. PMID:28148696

Revised Atmospheric Angular Momentum Series Related to Earth's Variable Rotation under Consideration of Surface Topography

NASA Technical Reports Server (NTRS)

Zhou, Y. H.; Salstein, D. A.; Chen, J. L.

2006-01-01

The atmospheric angular momentum is closely related to variations in the Earth rotation. The atmospheric excitation function (AEF), or namely atmospheric effective angular momentum function, is introduced in studying the atmospheric excitation of the Earth's variable rotation. It may be separated into two portions, i.e, the "wind" terms due to the atmospheric motion relative to the mantle and the "pressure" terms due to the variations of atmospheric mass distribution evident through surface pressure changes. The AEF wind terms during the period of 1948-2004 are re-processed from the NCEP/NCAR (National Centers for Environmental Prediction-National Center for Atmospheric Research) reanalysis 6-hourly wind and pressure fields. Some previous calculations were approximate, in that the wind terms were integrated from an isobaric lower boundary of 1000 hPa. To consider the surface topography effect, however, the AEF is computed by integration using the winds from the Earth's surface to 10 hPa, the top atmospheric model level, instead of from 1000 hPa. For these two cases, only a minor difference, equivalent to approx. 0.004 milliseconds in length-of-day variation, exists with respect to the axial wind term. However, considerable differences, equivalent to 5-6 milliarcseconds in polar motion, are found regarding equatorial wind terms. We further compare the total equatorial AEF (with and without the topographic effect) with the polar motion excitation function (PMEF) during the period of 1980-2003. The equatorial AEF gets generally closer to the PMEF, and improved coherences are found between them when the topography effect is included. Keywords: Atmospheric angular momentum, Atmospheric excitation function, Earth rotation, Topography, Wind, Pressure.

What can high frequency data tell us about hydrological and biogeochemical processes in a permafrost-underlain watershed that we do not already know?

NASA Astrophysics Data System (ADS)

Carey, S. K.; Shatilla, N. J.; Tang, W.

2017-12-01

Permafrost and frozen ground play a key role in the delivery of water and solutes from the landscape to the stream, and in biogeochemical cycling by acting as a cold season or semi-permanent aquitard. Conceptual models of permafrost hydrology have been well defined for over 40 years, yet renewed interest in the face of global climate change and rapid degradation of frozen ground has provided an opportunity to revisit previous paradigms. At the same time, new instruments and techniques to understand coupled hydrological and biogeochemical processes have emerged, providing a more nuanced view of northern systems. High-frequency sub-hourly measures of flows, water quality and biogeochemical parameters such as salinity and chromophoric dissolved organic matter (CDOM), along with eddy covariance systems provide considerable data, yet using this data to reveal new process information remains challenging. In this presentation, multi-year high frequency data sets of water, solute and carbon fluxes from Granger Creek, an instrumented alpine watershed with discontinuous permafrost within the Wolf Creek Research Basin, Yukon Territory, Canada, will be shown. While several decades of hydrometric and geochemical data exist for Granger Creek, inter-annual variability is considerable and makes evaluating long-term trends difficult. Insights derived from high-frequency sub-hourly salinity, CDOM and flow over recent years reveal that hysteresis loops among variables can be used to assess changing connectivity and flow paths as both magnitude and direction of loops can be used to infer landscape-scale linkages. These patterns highlight spatial connections among landscape units not previously observed, and identify periods when hydrological and biogeochemical cycles are coupled. Evaluation of these patterns at the headwater scale provides alternate hypotheses for how permafrost landscapes will respond to a changing climate.

Large river bed sediment characterization with low-cost sidecan sonar: Case studies from two setting in the Colorado (Arizona) and Penobscot (Maine) Rivers

USGS Publications Warehouse

Buscombe, Daniel D.; Grams, Paul E.; Melis, Theodore S.; Smith, Sean

2015-01-01

Here we discuss considerations in the use of sidescan sonar for riverbed sediment classification using examples from two large rivers, the Colorado River below Glen Canyon Dam in Arizona and the Upper Penobscot River in northern Maine (Figure 3). These case studies represent two fluvial systems that differ in recent history, physiography, sediment transport, and fluvial morphologies. The bed of the Colorado River in Glen Canyon National Recreation Area is predominantly graveled with extensive mats of submerged vegetation, and ephemeral surficial sand deposits exist below major tributaries. The bed is imaged periodically to assess the importance of substrate type and variability on rainbow trout spawning and juvenile rearing habitats and controls on aquatic invertebrate population dynamics. The Colorado River bed further below the dam in Grand Canyon National Park is highly dynamic. Tributary inputs of sand, gravel and boulders are spatially variable, and hydraulics of individual pools and eddies vary considerably in space and in response to varying dam operations, including experimental controlled flood releases to rebuild eroding sandbars. The bed encompasses the full range of noncohesive sediments, deposited in complicated spatial patterns. The mobile portion of the Penobscot River is generally more uniform, and consists predominantly of embedded gravels interspersed between bedrock outcrops with small isolated sand patches in sections with modest or low gradients. Patches of large cobbles, boulders and bedrock outcrops are present in the lower reaches of the river near locations of two recent dam removal projects but are of limited extent below the "head of tide" on the river. Aggregations of coarse materials often correspond to locations with abrupt bed elevation drops in the Upper Penobscot River.

Global economic impacts of climate variability and change during the 20th century.

PubMed

Estrada, Francisco; Tol, Richard S J; Botzen, Wouter J W

2017-01-01

Estimates of the global economic impacts of observed climate change during the 20th century obtained by applying five impact functions of different integrated assessment models (IAMs) are separated into their main natural and anthropogenic components. The estimates of the costs that can be attributed to natural variability factors and to the anthropogenic intervention with the climate system in general tend to show that: 1) during the first half of the century, the amplitude of the impacts associated with natural variability is considerably larger than that produced by anthropogenic factors and the effects of natural variability fluctuated between being negative and positive. These non-monotonic impacts are mostly determined by the low-frequency variability and the persistence of the climate system; 2) IAMs do not agree on the sign (nor on the magnitude) of the impacts of anthropogenic forcing but indicate that they steadily grew over the first part of the century, rapidly accelerated since the mid 1970's, and decelerated during the first decade of the 21st century. This deceleration is accentuated by the existence of interaction effects between natural variability and natural and anthropogenic forcing. The economic impacts of anthropogenic forcing range in the tenths of percentage of the world GDP by the end of the 20th century; 3) the impacts of natural forcing are about one order of magnitude lower than those associated with anthropogenic forcing and are dominated by the solar forcing; 4) the interaction effects between natural and anthropogenic factors can importantly modulate how impacts actually occur, at least for moderate increases in external forcing. Human activities became dominant drivers of the estimated economic impacts at the end of the 20th century, producing larger impacts than those of low-frequency natural variability. Some of the uses and limitations of IAMs are discussed.

Global economic impacts of climate variability and change during the 20th century

PubMed Central

Estrada, Francisco; Tol, Richard S. J.; Botzen, Wouter J. W.

2017-01-01

Estimates of the global economic impacts of observed climate change during the 20th century obtained by applying five impact functions of different integrated assessment models (IAMs) are separated into their main natural and anthropogenic components. The estimates of the costs that can be attributed to natural variability factors and to the anthropogenic intervention with the climate system in general tend to show that: 1) during the first half of the century, the amplitude of the impacts associated with natural variability is considerably larger than that produced by anthropogenic factors and the effects of natural variability fluctuated between being negative and positive. These non-monotonic impacts are mostly determined by the low-frequency variability and the persistence of the climate system; 2) IAMs do not agree on the sign (nor on the magnitude) of the impacts of anthropogenic forcing but indicate that they steadily grew over the first part of the century, rapidly accelerated since the mid 1970's, and decelerated during the first decade of the 21st century. This deceleration is accentuated by the existence of interaction effects between natural variability and natural and anthropogenic forcing. The economic impacts of anthropogenic forcing range in the tenths of percentage of the world GDP by the end of the 20th century; 3) the impacts of natural forcing are about one order of magnitude lower than those associated with anthropogenic forcing and are dominated by the solar forcing; 4) the interaction effects between natural and anthropogenic factors can importantly modulate how impacts actually occur, at least for moderate increases in external forcing. Human activities became dominant drivers of the estimated economic impacts at the end of the 20th century, producing larger impacts than those of low-frequency natural variability. Some of the uses and limitations of IAMs are discussed. PMID:28212384

TECHNOLOGICAL CONSIDERATIONS FOR PLANNING THE GLOBAL CARBON FUTURE

EPA Science Inventory

The atmospheric level of carbon dioxide (CO2) is the dominant variable in the anthropogenic influence of future global climate change. Thus, it is critical to understand the long-term factors affecting its level, especially the longer-range technological considerations. Most rece...

Estimation statistique de donnees manquantes en inventaire du cycle de vie

NASA Astrophysics Data System (ADS)

Moreau, Vincent

The main objective of the research work is to improve the quality of life cycle inventory data by developing a method to estimate missing data and corresponding uncertainties. Contrary to process-based models of mass and energy balance, this approach consists of statistical estimators which model processes from relatively small samples of usually high variability. The research hypothesis is as follows: the so called kriging estimator allows the combined estimation of missing data and their uncertainties in such ways that are more reliable than other linear estimators. Borrowed from spatial statistics, kriging is an estimator with several advantages, the flexibility associated with a choice of model function and the exact estimator property. In other words, kriging shows no statistical errors when estimating observed values, no data is averaged out. An interpretation of the kriging parameters specific to the problems of data uncertainty, offers more advantages. One parameter of the covariance function accounts for small scale variations of the data and taken as a proxy for uncertainty. Whether it be the variety of data sources, the scarcity of the data itself or both, each and every source adds to data variability and uncertainty. The kriging system of equations is therefore modified such as to integrate a factor of uncertainty specific to each observations. Comparisons between the modified and conventional forms of kriging can be drawn. The procedure is based on the relationship between technical specifications, more readily available independent variables, and the dependent material and energy flows of the processes under consideration. Such material and energy requirements as well as emissions are estimated over the entire life cycle of products and processes. The needs for additional data are relatively low compared to other approaches, namely extended input output analysis. For many products, processes and services, electricity generation and consumption account for a sizable share of the impacts. Hydroelectricity in particular is poorly represented within existing inventory data since production facilities vary considerably from one location to another. In other words, generic hydropower plants do not exist. Contrary to inventory flows, the technical specifications or characteristic variables of hydropower plants, such as the installed capacity, annual production or surface area of adjacent reservoirs, are usually publicly available. The kriging model is first tested on a data set which represents windmills of varying power capacity before it is applied to hydroelectricity. The experiment is divided according to data availability, on one hand the energy and materials required during construction, operation and maintenance of hydropower plants. The results show that estimation of inventory data can be improved thanks to kriging. When comparing different forms of kriging and linear regression, the kriging estimates are not only more precise but the standard deviations also cover the data more accurately. Where the observed data are incomplete, that is where inventory flows are missing for part of the observations, the estimation errors are lower for kriging than linear regression. Moreover, univariate kriging of inventory flows based on two characteristic variables, shows lower errors than its multivariate kin, cokriging. On average the statistical errors calculated from cross-validation are lower for kriging than they are for linear regression, whether the observed data are complete or not. The application of several characteristic variables improves the quality of the estimates when they are positively correlated. In addition, the modified form of kriging which accounts for degrees of uncertainty specific to each observations, results in a reduction in the variations of the estimated inventory data. That is, data variability is incorporated directly in the model. Estimates closer to more reliable observations are shown to be less uncertain and vice versa. For each of the data sets, different relationships between dependent and independent variables are tested, for example the linear, exponential, spherical and cubic covariance functions as well as a range of parameter values. For the analysis of electrical generation technologies, these results imply better estimates for data that are difficult to sample and therefore a simplified data collection process. In the case of site specific or variable processes such as hydroelectricity, the estimation of inventory data with kriging accounting for such data variability, proves more representative of the geographical or technological context. The quality of inventory data is consequently higher. Even if kriging has several advantages and its estimation errors are lower on average, some limitations to its application exist. (Abstract shortened by UMI.).

Climate Science Centers: An "Existence Theorem" for a Federal-University Partnership to Develop Actionable and Needs-Driven Science Agendas

NASA Astrophysics Data System (ADS)

Moore, B., III

2014-12-01

Climate Science Centers: An "Existence Theorem" for a Federal-University Partnership to Develop Actionable and Needs-Driven Science Agendas. Berrien Moore III (University of Oklahoma) The South Central Climate Science Center (CSC) is one of eight regional centers established by the Department of the Interior (DoI) under Secretarial Order 3289 to address the impacts of climate change on America's water, land, and other natural and cultural resources. Under DoI leadership and funding, these CSCs will provide scientific information tools and techniques to study impacts of climate change synthesize and integrate climate change impact data develop tools that the DoI managers and partners can use when managing the DOI's land, water, fish and wildlife, and cultural heritage resources (emphasis added) The network of Climate Science Centers will provide decision makers with the science, tools, and information they need to address the impacts of climate variability and change on their areas of responsibility. Note from Webster, a tool is a device for doing work; it makes outcomes more realizable and more cost effective, and, in a word, better. Prior to the existence of CSCs, the university and federal scientific world certainly contained a large "set" of scientists with considerable strength in the physical, biological, natural, and social sciences to address the complexities and interdisciplinary nature of the challenges in the areas of climate variability, change, impacts, and adaptation. However, this set of scientists were hardly an integrated community let alone a focused team, but rather a collection of distinguished researchers, educators, and practitioners that were working with disparate though at times linked objectives, and they were rarely aligning themselves formally to an overarching strategic pathway. In addition, data, models, research results, tools, and products were generally somewhat "disconnected" from the broad range of stakeholders. I should note also that NOAA's Regional Integrated Sciences and Assessments ( RISA) program is an earlier "Existence Theorem" for a Federal-University Partnership to Develop Actionable and Needs-Driven Science Agendas. This contribution will discuss the important cultural shift that has flowed from Secretarial Order 3289.

Using experimental data to reduce the single-building sigma of fragility curves: case study of the BRD tower in Bucharest, Romania

NASA Astrophysics Data System (ADS)

Perrault, Matthieu; Gueguen, Philippe; Aldea, Alexandru; Demetriu, Sorin

2013-12-01

The lack of knowledge concerning modelling existing buildings leads to signifiant variability in fragility curves for single or grouped existing buildings. This study aims to investigate the uncertainties of fragility curves, with special consideration of the single-building sigma. Experimental data and simplified models are applied to the BRD tower in Bucharest, Romania, a RC building with permanent instrumentation. A three-step methodology is applied: (1) adjustment of a linear MDOF model for experimental modal analysis using a Timoshenko beam model and based on Anderson's criteria, (2) computation of the structure's response to a large set of accelerograms simulated by SIMQKE software, considering twelve ground motion parameters as intensity measurements (IM), and (3) construction of the fragility curves by comparing numerical interstory drift with the threshold criteria provided by the Hazus methodology for the slight damage state. By introducing experimental data into the model, uncertainty is reduced to 0.02 considering S d ( f 1) as seismic intensity IM and uncertainty related to the model is assessed at 0.03. These values must be compared with the total uncertainty value of around 0.7 provided by the Hazus methodology.

Use of market segmentation to identify untapped consumer needs in vision correction surgery for future growth.

PubMed

Loarie, Thomas M; Applegate, David; Kuenne, Christopher B; Choi, Lawrence J; Horowitz, Diane P

2003-01-01

Market segmentation analysis identifies discrete segments of the population whose beliefs are consistent with exhibited behaviors such as purchase choice. This study applies market segmentation analysis to low myopes (-1 to -3 D with less than 1 D cylinder) in their consideration and choice of a refractive surgery procedure to discover opportunities within the market. A quantitative survey based on focus group research was sent to a demographically balanced sample of myopes using contact lenses and/or glasses. A variable reduction process followed by a clustering analysis was used to discover discrete belief-based segments. The resulting segments were validated both analytically and through in-market testing. Discontented individuals who wear contact lenses are the primary target for vision correction surgery. However, 81% of the target group is apprehensive about laser in situ keratomileusis (LASIK). They are nervous about the procedure and strongly desire reversibility and exchangeability. There exists a large untapped opportunity for vision correction surgery within the low myope population. Market segmentation analysis helped determine how to best meet this opportunity through repositioning existing procedures or developing new vision correction technology, and could also be applied to identify opportunities in other vision correction populations.

Crop Characteristics Research: Growth and Reflectance Analysis

NASA Technical Reports Server (NTRS)

Badhwar, G. D. (Principal Investigator)

1985-01-01

Much of the early research in remote sensing follows along developing spectral signatures of cover types. It was found, however, that a signature from an unknown cover class could not always be matched to a catalog value of known cover class. This approach was abandoned and supervised classification schemes followed. These were not efficient and required extensive training. It was obvious that data acquired at a single time could not separate cover types. A large portion of the proposed research has concentrated on modeling the temporal behavior of agricultural crops and on removing the need for any training data in remote sensing surveys; the key to which is the solution of the so-called 'signature extension' problem. A clear need to develop spectral estimaters of crop ontogenic stages and yield has existed even though various correlations have been developed. Considerable effort in developing techniques to estimate these variables was devoted to this work. The need to accurately evaluate existing canopy reflectance model(s), improve these models, use them to understand the crop signatures, and estimate leaf area index was the third objective of the proposed work. A synopsis of this research effort is discussed.

A modified approach to controller partitioning

NASA Technical Reports Server (NTRS)

Garg, Sanjay; Veillette, Robert J.

1993-01-01

The idea of computing a decentralized control law for the integrated flight/propulsion control of an aircraft by partitioning a given centralized controller is investigated. An existing controller partitioning methodology is described, and a modified approach is proposed with the objective of simplifying the associated controller approximation problem. Under the existing approach, the decentralized control structure is a variable in the partitioning process; by contrast, the modified approach assumes that the structure is fixed a priori. Hence, the centralized controller design may take the decentralized control structure into account. Specifically, the centralized controller may be designed to include all the same inputs and outputs as the decentralized controller; then, the two controllers may be compared directly, simplifying the partitioning process considerably. Following the modified approach, a centralized controller is designed for an example aircraft mode. The design includes all the inputs and outputs to be used in a specified decentralized control structure. However, it is shown that the resulting centralized controller is not well suited for approximation by a decentralized controller of the given structure. The results indicate that it is not practical in general to cast the controller partitioning problem as a direct controller approximation problem.

The evaluation of bulbar dysfunction in amyotrophic lateral sclerosis: survey of clinical practice patterns in the United States.

PubMed

Plowman, Emily K; Tabor, Lauren C; Wymer, James; Pattee, Gary

2017-08-01

Speech and swallowing impairments are highly prevalent in individuals with amyotrophic lateral sclerosis (ALS) and contribute to reduced quality of life, malnutrition, aspiration, pneumonia and death. Established practice parameters for bulbar dysfunction in ALS do not currently exist. The aim of this study was to identify current practice patterns for the evaluation of speech and swallowing function within participating Northeast ALS clinics in the United States. A 15-item survey was emailed to all registered NEALS centres. Thirty-eight sites completed the survey. The majority (92%) offered Speech-Language Pathology, augmentative and alternative communication (71%), and dietician (92%) health care services. The ALS Functional Rating Scale-Revised and body weight represented the only parameters routinely collected in greater then 90% of responding sites. Referral for modified barium swallow study was routinely utilised in only 27% of sites and the use of percutaneous gastrostomy tubes in ALS patient care was found to vary considerably. This survey reveals significant variability and inconsistency in the management of bulbar dysfunction in ALS across NEALS sites. We conclude that a great need exists for the development of bulbar practice guidelines in ALS clinical care to accurately detect and monitor bulbar dysfunction.

Serological surveillance reveals widespread influenza A H7 and H9 subtypes among chicken flocks in Egypt.

PubMed

Afifi, Manal A A; El-Kady, Magdy F; Zoelfakar, Sahar A; Abdel-Moneim, Ahmed Sayed; Abddel-Moneim, Ahmed Sayed

2013-02-01

Multiple avian influenza viruses' subtypes are circulating worldwide possessing serious threat to human populations and considered key contributors to the emergence of human influenza pandemics. This study aimed to identify the potential existence of H7 and H9 avian influenza infections circulating among chicken flocks in Egypt. Serum samples were collected from chicken flocks that experienced respiratory distresses and/or variable mortality rates. H7 and H9 virus infections were screened by haemagglutination inhibition assay using chicken erythrocytes. Serum samples were collected from 9 broiler, 12 breeder and 18 layer flocks. Out of 1,225 examined sera, 417 (34 %) from 14 flocks and 605 (49.4 %) from 21 flocks were found positive for H7 and H9, respectively. Prevalence of both H7 and H9 antibodies were higher in layer followed by breeder then broiler flocks. Special consideration should be paid to control influenza viruses in Egypt, as pandemic influenza strains may develop unnoticed given the presence of subclinical infections, and the possibility of re-assortment with the prevailing endemic H5N1 virus strains in Egypt do exist.

Romanticism and self-esteem among teen mothers.

PubMed

Medora, N P; von der Hellen, C

1997-01-01

This study examined teen mothers' romanticism and self-esteem. The Dean Romanticism Scale and the Bachman Self-esteem Scale were administered to 94 mothers between the ages of 13 and 18 in Southern California. The study also investigated the relationship between the dependent variables--romanticism and self-esteem--and ten independent variables--age, age of mother when first child was born, incidence of sexual abuse, incidence of abortion, current sexual activity, adoption considerations, current use of birth control, whether paternity was denied by the baby's father, whether the mother's parents were living together, and the quality of the relationship between the mother's parents. Results indicated that five variables were significantly related to romanticism--whether the teenager had a previous abortion, adoption considerations, current sexual activity, whether the parents were living together, and the quality of the relationship between the parents. Two variables were significantly related to self-esteem--age and current use of birth control.

The Importance of Protesters' Morals: Moral Obligation as a Key Variable to Understand Collective Action.

PubMed

Sabucedo, José-Manuel; Dono, Marcos; Alzate, Mónica; Seoane, Gloria

2018-01-01

Collective action and protest have become a normalized political behavior that in many cases defines the political agenda. The reasons why people take to the streets constitute a central subject within the study of social psychology. In the literature, three precedents of protest that have been established as central to the study of this phenomenon are: injustice, efficacy, and identity. But political action is also deeply related to moral values. This explains why in recent years some moral constructs have also been pointed out as predictors of collective action. Moral variables have been introduced into the literature with little consideration to how they relate to each other. Thus, work in this direction is needed. The general aim of this research is to differentiate moral obligation from moral norms and moral conviction, as well as to compare their ability to predict collective action. In order to do so, the research objectives are: (a) conceptualize and operationalize moral obligation (Study 1, N = 171); (b) test its predictive power for intention to participate in protests (Study 2, N = 622); and (c) test moral obligation in a real context (Study 3, N = 407). Results are encouraging, showing not only that moral obligation is different to moral conviction and moral norm, but also that it is a more effective predictor working both for intention and real participation. This work therefore presents moral obligation as a key precedent of protest participation, prompting its future use as a variable that can enhance existing predictive models of collective action. Results regarding other variables are also discussed.

Feasibility of conducting wetfall chemistry investigations around the Bowen Power Plant

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

Chen, N.C.J.; Patrinos, A.A.N.

1979-10-01

The feasibility of expanding the Meteorological Effects of Thermal Energy Releases - Oak Ridge National Laboratory (METER-ORNL) research at Bower Power Plant, a coal-fired power plant in northwest Georgia, to include wetfall chemistry is evaluated using results of similar studies around other power plants, several atmospheric washout models, analysis of spatial variability in precipitation, and field logistical considerations. An optimal wetfall chemistry network design is proposed, incorporating the inner portion of the existing rain-gauge network and augmented by additional sites to ensure adequate coverage of probable target areas. The predicted sulfate production rate differs by about four orders of magnitudemore » among the models reviewed with a pH of 3. No model can claim superiority over any other model without substantive data verification. The spatial uniformity in rain amount is evaluated using four storms that occurred at the METER-ORNL network. Values of spatial variability ranged from 8 to 31% and decreased as the mean rainfall increased. The field study of wetfall chemistry will require a minimum of 5 persons to operate the approximately 50 collectors covering an area of 740 km/sup 2/. Preliminary wetfall-only samples collected on an event basis showed lower pH and higher electrical conductivity of precipitation collected about 5 km downwind of the power plant relative to samples collected upwind. Wetfall samples collected on a weekly basis using automatic samplers, however, showed variable results, with no consistent pattern. This suggests the need for event sampling to minimize variable rain volume and multiple-source effects often associated with weekly samples.« less

The Importance of Protesters’ Morals: Moral Obligation as a Key Variable to Understand Collective Action

PubMed Central

Sabucedo, José-Manuel; Dono, Marcos; Alzate, Mónica; Seoane, Gloria

2018-01-01

Collective action and protest have become a normalized political behavior that in many cases defines the political agenda. The reasons why people take to the streets constitute a central subject within the study of social psychology. In the literature, three precedents of protest that have been established as central to the study of this phenomenon are: injustice, efficacy, and identity. But political action is also deeply related to moral values. This explains why in recent years some moral constructs have also been pointed out as predictors of collective action. Moral variables have been introduced into the literature with little consideration to how they relate to each other. Thus, work in this direction is needed. The general aim of this research is to differentiate moral obligation from moral norms and moral conviction, as well as to compare their ability to predict collective action. In order to do so, the research objectives are: (a) conceptualize and operationalize moral obligation (Study 1, N = 171); (b) test its predictive power for intention to participate in protests (Study 2, N = 622); and (c) test moral obligation in a real context (Study 3, N = 407). Results are encouraging, showing not only that moral obligation is different to moral conviction and moral norm, but also that it is a more effective predictor working both for intention and real participation. This work therefore presents moral obligation as a key precedent of protest participation, prompting its future use as a variable that can enhance existing predictive models of collective action. Results regarding other variables are also discussed. PMID:29636720

Factors Affecting Outcomes in Cochlear Implant Recipients Implanted With a Perimodiolar Electrode Array Located in Scala Tympani.

PubMed

Holden, Laura K; Firszt, Jill B; Reeder, Ruth M; Uchanski, Rosalie M; Dwyer, Noël Y; Holden, Timothy A

2016-12-01

To identify primary biographic and audiologic factors contributing to cochlear implant (CI) performance variability in quiet and noise by controlling electrode array type and electrode position within the cochlea. Although CI outcomes have improved over time, considerable outcome variability still exists. Biographic, audiologic, and device-related factors have been shown to influence performance. Examining CI recipients with consistent array type and electrode position may allow focused investigation into outcome variability resulting from biographic and audiologic factors. Thirty-nine adults (40 ears) implanted for at least 6 months with a perimodiolar electrode array known (via computed tomography [CT] imaging) to be in scala tympani participated. Test materials, administered CI only, included monosyllabic words, sentences in quiet and noise, and spectral ripple discrimination. In quiet, scores were high with mean word and sentence scores of 76 and 87%, respectively; however, sentence scores decreased by an average of 35 percentage points when noise was added. A principal components (PC) analysis of biographic and audiologic factors found three distinct factors, PC1 Age, PC2 Duration, and PC3 Pre-op Hearing. PC1 Age was the only factor that correlated, albeit modestly, with speech recognition in quiet and noise. Spectral ripple discrimination strongly correlated with speech measures. For these recipients with consistent electrode position, PC1 Age was related to speech recognition performance. Consistent electrode position may have contributed to high speech understanding in quiet. Inter-subject variability in noise may have been influenced by auditory/cognitive processing, known to decline with age, and mechanisms that underlie spectral resolution ability.

A Framework for Categorizing Important Project Variables

NASA Technical Reports Server (NTRS)

Parsons, Vickie S.

2003-01-01

While substantial research has led to theories concerning the variables that affect project success, no universal set of such variables has been acknowledged as the standard. The identification of a specific set of controllable variables is needed to minimize project failure. Much has been hypothesized about the need to match project controls and management processes to individual projects in order to increase the chance for success. However, an accepted taxonomy for facilitating this matching process does not exist. This paper surveyed existing literature on classification of project variables. After an analysis of those proposals, a simplified categorization is offered to encourage further research.

The Implicit Function Theorem and Non-Existence of Limit of Functions of Several Variables

ERIC Educational Resources Information Center

dos Santos, A. L. C.; da Silva, P. N.

2008-01-01

We use the Implicit Function Theorem to establish a result of non-existence of limit to a certain class of functions of several variables. We consider functions given by quotients such that both the numerator and denominator functions are null at the limit point. We show that the non-existence of the limit of such function is related with the…

Geophysical variables and behavior: LIII. Epidemiological considerations for incidence of cancer and depression in areas of frequent UFO reports.

PubMed

Persinger, M A

1988-12-01

Luminous phenomena and anomalous physical forces have been hypothesized to be generated by focal tectonic strain fields that precede earthquakes. If these geophysical processes exist, then their spatial and temporal density should be greatest during periods of protracted, localized UFO reports; they might be used as dosimetric indicators. Contemporary epidemiological data concerning the health risks of power frequency electromagnetic fields and radon gas levels (expected correlates of certain tectonic strain fields), suggest that increased incidence (odds ratios greater 1:3) of brain tumors and leukemia should be evident within "flap" areas. In addition the frequency of variants of temporal lobe lability, psychological depression and posttraumatic stress should be significantly elevated. UFO field investigators, because they have repeated, intermittent close proximity to these fields, are considered to be a particularly high risk population for these disorders.

Polarization Studies for the eRHIC Electron Storage Ring

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

Gianfelice-Wendt, Eliana; Tepikian, S.

A hadron/lepton collider with polarized beams has been under consideration by the scientific community since some years, in the U.S. and Europe. Among the various proposals, those by JLAB and BNL with polarized electron and proton beams are currently under closer study in the U.S. Experimenters call for the simultaneous storage of electron bunches with both spin helicity. In the BNL based Ring-Ring design, electrons are stored at top energy in a ring to be accommodated in the existing RHIC tunnel. The transversely polarized electron beam is injected into the storage ring at variable energies, between 5 and 18 GeV.more » Polarization is brought into the longitudinal direction at the IP by a couple of spin rotators. In this paper results of first studies of the attainable beam polarization level and lifetime in the storage ring at 18 GeV are presented.« less

Sharp Contradiction for Local-Hidden-State Model in Quantum Steering.

PubMed

Chen, Jing-Ling; Su, Hong-Yi; Xu, Zhen-Peng; Pati, Arun Kumar

2016-08-26

In quantum theory, no-go theorems are important as they rule out the existence of a particular physical model under consideration. For instance, the Greenberger-Horne-Zeilinger (GHZ) theorem serves as a no-go theorem for the nonexistence of local hidden variable models by presenting a full contradiction for the multipartite GHZ states. However, the elegant GHZ argument for Bell's nonlocality does not go through for bipartite Einstein-Podolsky-Rosen (EPR) state. Recent study on quantum nonlocality has shown that the more precise description of EPR's original scenario is "steering", i.e., the nonexistence of local hidden state models. Here, we present a simple GHZ-like contradiction for any bipartite pure entangled state, thus proving a no-go theorem for the nonexistence of local hidden state models in the EPR paradox. This also indicates that the very simple steering paradox presented here is indeed the closest form to the original spirit of the EPR paradox.

Geophysical variables and behavior: LIII. Epidemiological considerations for incidence of cancer and depression in areas of frequent UFO reports

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

Persinger, M.A.

Luminous phenomena and anomalous physical forces have been hypothesized to be generated by focal tectonic strain fields that precede earthquakes. If these geophysical processes exist, then their spatial and temporal density should be greatest during periods of protracted, localized UFO reports; they might be used as dosimetric indicators. Contemporary epidemiological data concerning the health risks of power frequency electromagnetic fields and radon gas levels (expected correlates of certain tectonic strain fields), suggest that increased incidence (odds ratios greater 1:3) of brain tumors and leukemia should be evident within flap areas. In addition the frequency of variants of temporal lobe lability,more » psychological depression and posttraumatic stress should be significantly elevated. UFO field investigators, because they have repeated, intermittent close proximity to these fields, are considered to be a particularly high risk population for these disorders. 22 references.« less

Thermochronologic constraints on the tectonic evolution of the western Antarctic Peninsula in late Mesozoic and Cenozoic times

USGS Publications Warehouse

Brix, M.R.; Faundez, V.; Hervé, F.; Solari, M.; Fernandez, J.; Carter, A.; Stöckhert, B.

2007-01-01

West of the Antarctic Peninsula, oceanic lithosphere of the Phoenix plate has been subducted below the Antarctic plate. Subduction has ceased successively from south to north over the last 65 Myr. An influence of this evolution on the segmentation of the crust in the Antarctic plate is disputed. Opposing scenarios consider effects of ridge crest – trench interactions with the subduction zone or differences in slip along a basal detachment in the overriding plate. Fission track (FT) analyses on apatites and zircons may detect thermochronologic patterns to test these hypotheses. While existing data concentrate on accretionary processes in Palmer Land, new data extend information to the northern part of the Antarctic Peninsula. Zircons from different geological units over wide areas of the Antarctic Peninsula yield fission track ages between 90 and 80 Ma, indicating a uniform regional cooling episode. Apatite FT ages obtained so far show considerable regional variability

A state-of-practice survey of policy, plan, and program assessment in Canadian provinces

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

Noble, Bram F

2004-04-01

Since the introduction of the 1999 Canadian Cabinet Directive on the environmental assessment of policies, plans, and programs (PPPs), higher-order environmental assessment has been receiving increased attention in Canada. However, while practices and systems are advancing at the federal level, there has been very little attention given to recent developments in PPP assessment at the provincial level. This paper presents the results of a Canada-wide survey of PPP assessment principles and practices in 10 Canadian provincial EA jurisdictions. The findings indicate that there exists considerable variability in the provisions for and practice of PPP assessment amongst Canadian provinces, with onlymore » Saskatchewan, Ontario, and Quebec identifying recent practice experience. Included amongst the main barriers to effective implementation at the provincial level are the lack of legislative requirements for strategic EA, and the limited understanding of the nature and benefits of higher-order impact assessment.« less

Ontogenetic and diel variation in stream habitat use by brook trout (Salvelinus fontinalis) in a headwater stream

USGS Publications Warehouse

Johnson, J. H.; Ross, R.M.; Dropkin, D.S.; Redell, L.A.

2011-01-01

Although considerable information exists on habitat use by stream salmonids, only a small portion has quantitatively examined diurnal and nocturnal habitat variation. We examined diel variation in habitat use by age-0 and age-1+ brook trout (Salvelinus fontinalis) during summer and autumn in a headwater stream in northern Pennsylvania. Habitat variables measured included cover, depth, substrate, and velocity. The most pronounced diel variation occurred in the use of cover during both seasons. Both age-0 brook trout and age-1+ trout were associated with less cover at night. Age-0 brook trout occupied swifter water during the day than at night during both seasons, but the difference was not significant. Increased cover, depth, and substrate size governed the habitat of age-1+ brook trout. Our findings support the need for a better understanding of diel differences in habitat use of stream salmonids when considering habitat enhancement and protection.

Evaluation on Collaborative Satisfaction for Project Management Team in Integrated Project Delivery Mode

NASA Astrophysics Data System (ADS)

Zhang, L.; Li, Y.; Wu, Q.

2013-05-01

Integrated Project Delivery (IPD) is a newly-developed project delivery approach for construction projects, and the level of collaboration of project management team is crucial to the success of its implementation. Existing research has shown that collaborative satisfaction is one of the key indicators of team collaboration. By reviewing the literature on team collaborative satisfaction and taking into consideration the characteristics of IPD projects, this paper summarizes the factors that influence collaborative satisfaction of IPD project management team. Based on these factors, this research develops a fuzzy linguistic method to effectively evaluate the level of team collaborative satisfaction, in which the authors adopted the 2-tuple linguistic variables and 2-tuple linguistic hybrid average operators to enhance the objectivity and accuracy of the evaluation. The paper demonstrates the practicality and effectiveness of the method through carrying out a case study with the method.

Economic considerations in the care of patients with head and neck malignancies.

PubMed

Pfister, D G; Ruchlin, H S; Elkin, E B

1997-05-01

In an era of cost-consciousness and managed care, quality concerns practice variability attributed to nonmedical factors, and growing attention to outcomes research, there is increasing interest in the economics of malignant disease. This review explores economic issues pertinent to the management of patients with head and neck malignancies. Using economic principles to evaluate medical practice does not uniformly mean that less money should be spent; rather, the intention is to optimize efficiency in the use of limited resources. Accordingly costs are best evaluated in the context of other outcomes of interest. The available economic literature for head and neck tumors is limited; it is often compromised by the use of facility charges as a proxy for true costs and the adoption of a truncated economic perspective. Given the potential health policy implications of such studies, their methodologies and results warrant careful scrutiny. Many opportunities exist for further research.

Structure property relationships in gallium oxide thin films grown by pulsed laser deposition [Structure property relationships in Ga 2O 3 thin films grown by pulsed laser deposition

DOE PAGES

Garten, Lauren M.; Zakutayev, Andriy; Perkins, John D.; ...

2016-11-21

Beta-gallium oxide (β-Ga 2O 3) is of increasing interest to the optoelectronic community for transparent conductor and power electronic applications. Considerable variability exists in the literature on the growth and doping of Ga 2O 3 films, especially as a function of growth approach, temperature, and oxygen partial pressure. Here pulsed laser deposition (PLD) was used to grow high-quality β-Ga 2O 3 films on (0001) sapphire and (–201) Ga 2O 3 single crystals and to explore the growth, stability, and dopability of these films as function of temperature and oxygen partial pressure. As a result, there is a strong temperature dependencemore » to the phase formation, morphology, and electronic properties of β-Ga 2O 3 from 350 to 550 °C.« less

[Siblings of chronically ill adolescents: does chronic illness have effects on their development potentials?].

PubMed

Boeger, A; Seiffge-Krenke, I

1996-12-01

Sibling relationships have been studied by developmental psychologists for a long time. Whereas previous research on this topic was focused on examining variables such as gender, age differences and sibling sequence, recent research efforts have directed more attention towards understanding the functions siblings perform for one another and what kinds of emotional relationships exist between them. In this regard, we became interested in identifying the special burdens which siblings of chronically sick children and adolescents must deal with. Two case studies are presented here selected from the research findings obtained from investigation in our research project. Coping with chronic illness as seen in juvenile diabetes. These case studies demonstrate that healthy siblings of chronically sick adolescents may be subjected to considerable burdens and illustrate, as well, the kinds of coping mechanisms siblings adopt in order to deal with them.

Preliminary considerations for extraction of thermal effect from magma

NASA Astrophysics Data System (ADS)

Hickox, C. E.; Dunn, J. C.

Simplified mathematical models are developed to describe the extraction of thermal energy from magma based on the concept of a counter-flow heat exchanger inserted into the magma body. Analytical solutions are used to investigate influence of the basic variables on electric power production. Calculations confirm that the proper heat exchanger flow path is down the annulus with hot fluid returning to the surface through the central core. The core must be insulated from the annulus to achieve acceptable wellhead temperatures, but this insulation thickness can be quite small. The insulation is effective in maintaining the colder annular flow below expected formation temperatures so that a net beat gain from the formation above a magma body is predicted. The analynes show that optimum flow rates exist that maximize electric power production. These optimum flow rates are functions of the heat transfer coefficients that describe magma energy extraction.

Investigating data entry task performance on a laptop under the impact of vibration: the effect of color.

PubMed

Mallick, Zulquernain

2007-01-01

The last 20 years have seen a tremendous growth in mobile computing and wireless communications and services. An experimental study was conducted to explore the effect of text/background color on a laptop computing system along with variable environmental vibration on operators' data entry task performance in moving automobiles. The operators' performance was measured in terms of the number of characters entered per minute without spaces (NCEPMWS) on a laptop computing system. The subjects were divided into 3 categories, namely, Novices, Intermediates and Experts. Findings suggest a re-evaluation of existing laptop designs taking ergonomics into consideration. It appears that proper selection of text/background color on the laptop coupled with controlled vehicular speed could result in a better quality of interaction between human and laptops and it could also resolve the problem of poor data entry task performance.

Tree ferns: monophyletic groups and their relationships as revealed by four protein-coding plastid loci.

PubMed

Korall, Petra; Pryer, Kathleen M; Metzgar, Jordan S; Schneider, Harald; Conant, David S

2006-06-01

Tree ferns are a well-established clade within leptosporangiate ferns. Most of the 600 species (in seven families and 13 genera) are arborescent, but considerable morphological variability exists, spanning the giant scaly tree ferns (Cyatheaceae), the low, erect plants (Plagiogyriaceae), and the diminutive endemics of the Guayana Highlands (Hymenophyllopsidaceae). In this study, we investigate phylogenetic relationships within tree ferns based on analyses of four protein-coding, plastid loci (atpA, atpB, rbcL, and rps4). Our results reveal four well-supported clades, with genera of Dicksoniaceae (sensu ) interspersed among them: (A) (Loxomataceae, (Culcita, Plagiogyriaceae)), (B) (Calochlaena, (Dicksonia, Lophosoriaceae)), (C) Cibotium, and (D) Cyatheaceae, with Hymenophyllopsidaceae nested within. How these four groups are related to one other, to Thyrsopteris, or to Metaxyaceae is weakly supported. Our results show that Dicksoniaceae and Cyatheaceae, as currently recognised, are not monophyletic and new circumscriptions for these families are needed.

Statistics Anxiety Update: Refining the Construct and Recommendations for a New Research Agenda.

PubMed

Chew, Peter K H; Dillon, Denise B

2014-03-01

Appreciation of the importance of statistics literacy for citizens of a democracy has resulted in an increasing number of degree programs making statistics courses mandatory for university students. Unfortunately, empirical evidence suggests that students in nonmathematical disciplines (e.g., social sciences) regard statistics courses as the most anxiety-inducing course in their degree programs. Although a literature review exists for statistics anxiety, it was done more than a decade ago, and newer studies have since added findings for consideration. In this article, we provide a current review of the statistics anxiety literature. Specifically, related variables, definitions, and measures of statistics anxiety are reviewed with the goal of refining the statistics anxiety construct. Antecedents, effects, and interventions of statistics anxiety are also reviewed to provide recommendations for statistics instructors and for a new research agenda. © The Author(s) 2014.

Clearing the haze: the complexities and challenges of research on state marijuana laws.

PubMed

Choo, Esther K; Emery, Sherry L

2017-04-01

As states increasingly liberalize marijuana laws, high-quality research is needed that will inform the public and policymakers about the health and societal impact of these laws. However, there are many challenges to studying marijuana policy, including the heterogeneity of the drug and its use, the variability in the laws and their implementation from state to state, the need to capture a wide variety of relevant outcomes, and the poorly understood influence of marijuana commercialization. Furthermore, current instruments generally fail to distinguish between types of users and lack accurate and detailed measures of use. This review provides a background on marijuana laws in the United States and an overview of existing policy research, discusses methodological considerations when planning analysis of state marijuana laws, and highlights specific topics needing further development and investigation. © 2016 New York Academy of Sciences.

On FIA Variables For Ecological Use

Treesearch

David C. Chojnacky

2001-01-01

The Forest Inventory and Analysis (FIA) program collects or calculates over 300 variables for its national network of permanent forest plots. However, considerable ecological analysis can be done with only a few key variables. Two examples--Mexican spotted owl habitat in New Mexico and down deadwood in Maine--are used to illustrate the potential of FIA data for...

Laser Scanning Systems and Techniques in Rockfall Source Identification and Risk Assessment: A Critical Review

NASA Astrophysics Data System (ADS)

Fanos, Ali Mutar; Pradhan, Biswajeet

2018-04-01

Rockfall poses risk to people, their properties and to transportation ways in mountainous and hilly regions. This catastrophe shows various characteristics such as vast distribution, sudden occurrence, variable magnitude, strong fatalness and randomicity. Therefore, prediction of rockfall phenomenon both spatially and temporally is a challenging task. Digital Terrain model (DTM) is one of the most significant elements in rockfall source identification and risk assessment. Light detection and ranging (LiDAR) is the most advanced effective technique to derive high-resolution and accurate DTM. This paper presents a critical overview of rockfall phenomenon (definition, triggering factors, motion modes and modeling) and LiDAR technique in terms of data pre-processing, DTM generation and the factors that can be obtained from this technique for rockfall source identification and risk assessment. It also reviews the existing methods that are utilized for the evaluation of the rockfall trajectories and their characteristics (frequency, velocity, bouncing height and kinetic energy), probability, susceptibility, hazard and risk. Detail consideration is given on quantitative methodologies in addition to the qualitative ones. Various methods are demonstrated with respect to their application scales (local and regional). Additionally, attention is given to the latest improvement, particularly including the consideration of the intensity of the phenomena and the magnitude of the events at chosen sites.

Use of mobile devices in community health care: barriers and solutions to implementation.

PubMed

Turner, Christopher

2016-02-01

Mobile devices allow clinicians to access electronic clinical systems away from traditional base locations. They have contributed to increased productivity and efficiency, and clinical staff also cite benefits to patient care. A selection of NHS trusts have participated in a national pilot to explore the benefits and drawbacks of this technology. Clinical engagement with frontline staff is essential to ensure the staff feel valued, listened to, and fully involved to ensure any change to existing practice is successful. Moreover, the training needs of the workforce require careful consideration. The provision of information technology (IT) support services is fundamental to ensure that staff receive the necessary assistance with any functionality issues they may experience with mobile devices to minimise the effect on clinical practice. Variability in internet connectivity may present as a challenge to clinical staff, and the benefits of complimentary offline working solutions should be considered. Barriers to the successful use of mobile devices should be reported as this may have a negative clinical effect on the safe delivery of patient care. Clinical staff need to be mindful of their obligations in relation to information governance, and should appreciate that the same consideration needs to be given to both paper and electronic records.

Report from a forum on US heart allocation policy.

PubMed

Kobashigawa, J A; Johnson, M; Rogers, J; Vega, J D; Colvin-Adams, M; Edwards, L; Meyer, D; Luu, M; Reinsmoen, N; Dipchand, A I; Feldman, D; Kormos, R; Mancini, D; Webber, S

2015-01-01

Since the latest revision in US heart allocation policy (2006), the landscape and volume of transplant waitlists have changed considerably. Advances in mechanical circulatory support (MCS) prolong survival, but Status 1A mortality remains high. Several patient subgroups may be disadvantaged by current listing criteria and geographical disparity remains in waitlist time. This forum on US heart allocation policy was organized to discuss these issues and highlight concepts for consideration in the policy development process. A 25-question survey on heart allocation policy was conducted. Among attendees/respondents were 84 participants with clinical/published experience in heart transplant representing 51 US transplant centers, and OPTN/UNOS and SRTR representatives. The survey results and forum discussions demonstrated very strong interest in change to a further-tiered system, accounting for disadvantaged subgroups and lowering use of exceptions. However, a heart allocation score is not yet viable due to the long-term viability of variables (used in the score) in an ever-developing field. There is strong interest in more refined prioritization of patients with MCS complications, highly sensitized patients and those with severe arrhythmias or restrictive physiology. There is also strong interest in distribution by geographic boundaries modified according to population. Differences of opinion exist between small and large centers.

[Correlation of dental age and anthropometric parametres of the overall growth and development in children].

PubMed

Triković-Janjić, Olivera; Apostolović, Mirjana; Janosević, Mirjana; Filipović, Gordana

2008-02-01

Anthropometric methods of measuring the whole body and body parts are the most commonly applied methods of analysing the growth and development of children. Anthropometric measures are interconnected, so that with growth and development the change of one of the parameters causes the change of the other. The aim of the paper was to analyse whether dental development follows the overall growth and development and what the ratio of this interdependence is. The research involved a sample of 134 participants, aged between 6 and 8 years. Dental age was determined as the average of the sum of existing permanent teeth from the participants aged 6, 7 and 8. With the aim of analysing physical growth and development, commonly accepted anthropometric indexes were applied: height, weight, circumference of the head, the chest cavity at its widest point, the upper arm, the abdomen, the thigh and thickness of the epidermis. The dimensions were measured according to the methodology of the International Biological Programme. The influence of the pertinent variables' related size on the analysed variable was deter mined by the statistical method of multivariable regression. The middle values of all the anthropometric parametres, except for the thickness of the epidermis, were slightly bigger with male participants, and the circumference of the chest cavity was statistically considerably bigger (p < 0.05). The results of anthropometric measurement showed in general a distinct homogeneity not only of the sample group but also within gender, in relation to all the dimensions, excyt for the thickness of the epidermis. The average of the dental age of the participants was 10.36, (10.42 and 10.31 for females and males respectively). Considerable correlation (R = 0.59) with high statistical significance (p < 0.001) was determined between dental age and the set of anthropometric parameters of general growth and development. There is a considerable positive correlation (R = 0.59) between dental age and anthropometric parameters of general growth and development, which confirms that dental development follows the overall growth and development of children, aged between 6 and 8 years.

Effects of sources of variability on sample sizes required for RCTs, applied to trials of lipid-altering therapies on carotid artery intima-media thickness.

PubMed

Gould, A Lawrence; Koglin, Joerg; Bain, Raymond P; Pinto, Cathy-Anne; Mitchel, Yale B; Pasternak, Richard C; Sapre, Aditi

2009-08-01

Studies measuring progression of carotid artery intima-media thickness (cIMT) have been used to estimate the effect of lipid-modifying therapies cardiovascular event risk. The likelihood that future cIMT clinical trials will detect a true treatment effect is estimated by leveraging results from prior studies. The present analyses assess the impact of between- and within-study variability based on currently published data from prior clinical studies on the likelihood that ongoing or future cIMT trials will detect the true treatment effect of lipid-modifying therapies. Published data from six contemporary cIMT studies (ASAP, ARBITER 2, RADIANCE 1, RADIANCE 2, ENHANCE, and METEOR) including data from a total of 3563 patients were examined. Bayesian and frequentist methods were used to assess the impact of between study variability on the likelihood of detecting true treatment effects on 1-year cIMT progression/regression and to provide a sample size estimate that would specifically compensate for the effect of between-study variability. In addition to the well-described within-study variability, there is considerable between-study variability associated with the measurement of annualized change in cIMT. Accounting for the additional between-study variability decreases the power for existing study designs. In order to account for the added between-study variability, it is likely that future cIMT studies would require a large increase in sample size in order to provide substantial probability (> or =90%) to have 90% power of detecting a true treatment effect.Limitation Analyses are based on study level data. Future meta-analyses incorporating patient-level data would be useful for confirmation. Due to substantial within- and between-study variability in the measure of 1-year change of cIMT, as well as uncertainty about progression rates in contemporary populations, future study designs evaluating the effect of new lipid-modifying therapies on atherosclerotic disease progression are likely to be challenged by large sample sizes in order to demonstrate a true treatment effect.

Aggregate Auto Travel Forecasting : State of the Art and Suggestions for Future Research

DOT National Transportation Integrated Search

1976-12-01

The report reviews existing forecasting models of auto vehicle miles of travel (VMT), and presents evidence that such models incorrectly omit time cost and spatial form variables. The omission of these variables biases parameter estimates in existing...

Ergonomic Considerations for the Human Environment: Color Treatment, Lighting, and Furniture Selection.

ERIC Educational Resources Information Center

Robertson, Michelle M.

1992-01-01

Discusses ergonomic design considerations for library media centers. Specific design variables, including temperature and humidity, noise, illumination, color, and windows are discussed; and computer workstation design requirements are presented that address furniture and keyboard design, monitor and display features, software issues, and…

Cultural and Cognitive Considerations in the Prevention of American Indian Adolescent Suicide.

ERIC Educational Resources Information Center

La Framboise, Teresa D.; Big Foot, Delores Subia

1988-01-01

Describes cultural considerations associated with American Indian adolescents coping within a transactional, cognitive-phenomenological framework. Discusses select cultural values and beliefs of American Indians associated with death in terms of person variables and situational demand characteristics that interplay in coping process. Suggests…

Rapid Communication: Large exploitable genetic variability exists to shorten age at slaughter in cattle.

PubMed

Berry, D P; Cromie, A R; Judge, M M

2017-10-01

Apprehension among consumers is mounting on the efficiency by which cattle convert feedstuffs into human edible protein and energy as well as the consequential effects on the environment. Most (genetic) studies that attempt to address these issues have generally focused on efficiency metrics defined over a certain time period of an animal's life cycle, predominantly the period representing the linear phase of growth. The age at which an animal reaches the carcass specifications for slaughter, however, is also known to vary between breeds; less is known on the extent of the within-breed variability in age at slaughter. Therefore, the objective of the present study was to quantify the phenotypic and genetic variability in the age at which cattle reach a predefined carcass weight and subcutaneous fat cover. A novel trait, labeled here as the deviation in age at slaughter (DAGE), was represented by the unexplained variability from a statistical model, with age at slaughter as the dependent variable and with the fixed effects, among others, of carcass weight and fat score (scale 1 to 15 scored by video image analysis of the carcass at slaughter). Variance components for DAGE were estimated using either a 2-step approach (i.e., the DAGE phenotype derived first and then variance components estimated) or a 1-step approach (i.e., variance components for age at slaughter estimated directly in a mixed model that included the fixed effects of, among others, carcass weight and carcass fat score as well as a random direct additive genetic effect). The raw phenotypic SD in DAGE was 44.2 d. The genetic SD and heritability for DAGE estimated using the 1-step or 2-step models varied from 14.2 to 15.1 d and from 0.23 to 0.26 (SE 0.02), respectively. Assuming the (genetic) variability in the number of days from birth to reaching a desired carcass specifications can be exploited without any associated unfavorable repercussions, considerable potential exists to improve not only the (feed) efficiency of the animal and farm system but also the environmental footprint of the system. The beauty of the approach proposed, relative to strategies that select directly for the feed intake complex and enteric methane emissions, is that data on age at slaughter are generally readily available. Of course, faster gains may potentially be achieved if a dual objective of improving animal efficiency per day coupled with reduced days to slaughter was embarked on.

METHODS FOR INTEGRATING ENVIRONMENTAL CONSIDERATIONS INTO CHEMICAL PROCESS DESIGN DECISIONS

EPA Science Inventory

The objective of this cooperative agreement was to postulate a means by which an engineer could routinely include environmental considerations in day-to-day conceptual design problems; a means that could easily integrate with existing design processes, and thus avoid massive retr...

Comparing meta-analysis and ecological-longitudinal analysis in time-series studies. A case study of the effects of air pollution on mortality in three Spanish cities.

PubMed

Saez, M; Figueiras, A; Ballester, F; Pérez-Hoyos, S; Ocaña, R; Tobías, A

2001-06-01

The objective of this paper is to introduce a different approach, called the ecological-longitudinal, to carrying out pooled analysis in time series ecological studies. Because it gives a larger number of data points and, hence, increases the statistical power of the analysis, this approach, unlike conventional ones, allows the complementation of aspects such as accommodation of random effect models, of lags, of interaction between pollutants and between pollutants and meteorological variables, that are hardly implemented in conventional approaches. The approach is illustrated by providing quantitative estimates of the short-term effects of air pollution on mortality in three Spanish cities, Barcelona, Valencia and Vigo, for the period 1992-1994. Because the dependent variable was a count, a Poisson generalised linear model was first specified. Several modelling issues are worth mentioning. Firstly, because the relations between mortality and explanatory variables were non-linear, cubic splines were used for covariate control, leading to a generalised additive model, GAM. Secondly, the effects of the predictors on the response were allowed to occur with some lag. Thirdly, the residual autocorrelation, because of imperfect control, was controlled for by means of an autoregressive Poisson GAM. Finally, the longitudinal design demanded the consideration of the existence of individual heterogeneity, requiring the consideration of mixed models. The estimates of the relative risks obtained from the individual analyses varied across cities, particularly those associated with sulphur dioxide. The highest relative risks corresponded to black smoke in Valencia. These estimates were higher than those obtained from the ecological-longitudinal analysis. Relative risks estimated from this latter analysis were practically identical across cities, 1.00638 (95% confidence intervals 1.0002, 1.0011) for a black smoke increase of 10 microg/m(3) and 1.00415 (95% CI 1.0001, 1.0007) for a increase of 10 microg/m(3) of sulphur dioxide. Because the statistical power is higher than in the individual analysis more interactions were statistically significant, especially those among air pollutants and meteorological variables. Air pollutant levels were related to mortality in the three cities of the study, Barcelona, Valencia and Vigo. These results were consistent with similar studies in other cities, with other multicentric studies and coherent with both, previous individual, for each city, and multicentric studies for all three cities.

Transgenes in Mexican maize: molecular evidence and methodological considerations for GMO detection in landrace populations

PubMed Central

PIÑEYRO-NELSON, A; VAN HEERWAARDEN, J; PERALES, H R; SERRATOS-HERNÁNDEZ, J A; RANGEL, A; HUFFORD, M B; GEPTS, P; GARAY-ARROYO, A; RIVERA-BUSTAMANTE, R; ÁLVAREZ-BUYLLA, E R

2009-01-01

A possible consequence of planting genetically modified organisms (GMOs) in centres of crop origin is unintended gene flow into traditional landraces. In 2001, a study reported the presence of the transgenic 35S promoter in maize landraces sampled in 2000 from the Sierra Juarez of Oaxaca, Mexico. Analysis of a large sample taken from the same region in 2003 and 2004 could not confirm the existence of transgenes, thereby casting doubt on the earlier results. These two studies were based on different sampling and analytical procedures and are thus hard to compare. Here, we present new molecular data for this region that confirm the presence of transgenes in three of 23 localities sampled in 2001. Transgene sequences were not detected in samples taken in 2002 from nine localities, while directed samples taken in 2004 from two of the positive 2001 localities were again found to contain transgenic sequences. These findings suggest the persistence or re-introduction of transgenes up until 2004 in this area. We address variability in recombinant sequence detection by analyzing the consistency of current molecular assays. We also present theoretical results on the limitations of estimating the probability of transgene detection in samples taken from landraces. The inclusion of a limited number of female gametes and, more importantly, aggregated transgene distributions may significantly lower detection probabilities. Our analytical and sampling considerations help explain discrepancies among different detection efforts, including the one presented here, and provide considerations for the establishment of monitoring protocols to detect the presence of transgenes among structured populations of landraces. PMID:19143938

Transgenes in Mexican maize: molecular evidence and methodological considerations for GMO detection in landrace populations.

PubMed

Piñeyro-Nelson, A; Van Heerwaarden, J; Perales, H R; Serratos-Hernández, J A; Rangel, A; Hufford, M B; Gepts, P; Garay-Arroyo, A; Rivera-Bustamante, R; Alvarez-Buylla, E R

2009-02-01

A possible consequence of planting genetically modified organisms (GMOs) in centres of crop origin is unintended gene flow into traditional landraces. In 2001, a study reported the presence of the transgenic 35S promoter in maize landraces sampled in 2000 from the Sierra Juarez of Oaxaca, Mexico. Analysis of a large sample taken from the same region in 2003 and 2004 could not confirm the existence of transgenes, thereby casting doubt on the earlier results. These two studies were based on different sampling and analytical procedures and are thus hard to compare. Here, we present new molecular data for this region that confirm the presence of transgenes in three of 23 localities sampled in 2001. Transgene sequences were not detected in samples taken in 2002 from nine localities, while directed samples taken in 2004 from two of the positive 2001 localities were again found to contain transgenic sequences. These findings suggest the persistence or re-introduction of transgenes up until 2004 in this area. We address variability in recombinant sequence detection by analyzing the consistency of current molecular assays. We also present theoretical results on the limitations of estimating the probability of transgene detection in samples taken from landraces. The inclusion of a limited number of female gametes and, more importantly, aggregated transgene distributions may significantly lower detection probabilities. Our analytical and sampling considerations help explain discrepancies among different detection efforts, including the one presented here, and provide considerations for the establishment of monitoring protocols to detect the presence of transgenes among structured populations of landraces.

Some Considerations Necessary for a Viable Theory of Human Memory.

ERIC Educational Resources Information Center

Sietsema, Douglas J.

Empirical research is reviewed in the area of cognitive psychology pertaining to models of human memory. Research evidence and theoretical considerations are combined to develop guidelines for future theory development related to the human memory. The following theoretical constructs and variables are discussed: (1) storage versus process…

X-Ray Variability of BL Lac Objects

NASA Astrophysics Data System (ADS)

McHardy, Ian

I present an overview of the X-ray temporal and spectral variability of BL Lacs on both short and long timescales. The previously observed behaviour of short (~days) flares superimposed on a relatively steady `quiescent' level is still broadly correct. However, for the brighter BL Lacs, the well sampled lightcurves from the RXTE ASM show that the `quiescent' level also varies considerably on timescales of ~100 days in a manner similar to that seen in Optically Violently Variable Quasars (OVVs) such as 3C279 and 3C273. Possible reasons for this behaviour are discussed. For the large majority of BL Lacs the soft and medium energy X-ray bands are dominated by synchrotron emission and, unlike the case of OVVs, the emission mechanism is not in doubt. Most interest then centres on the structure of the emitting region, and the electron acceleration processes, particularly during outbursts. That structure, and the acceleration processes, can be investigated by consideration of the spectral variability during flares, which is not simple. I review the observations of spectral variability and consider the evidence for and against homogeneous models. I also briefly compare the X-ray spectral variability of BL Lacs with that of OVVs such as 3C273.

Small-scale temporal and spatial variability in the abundance of plastic pellets on sandy beaches: Methodological considerations for estimating the input of microplastics.

PubMed

Moreira, Fabiana Tavares; Prantoni, Alessandro Lívio; Martini, Bruno; de Abreu, Michelle Alves; Stoiev, Sérgio Biato; Turra, Alexander

2016-01-15

Microplastics such as pellets have been reported for many years on sandy beaches around the globe. Nevertheless, high variability is observed in their estimates and distribution patterns across the beach environment are still to be unravelled. Here, we investigate the small-scale temporal and spatial variability in the abundance of pellets in the intertidal zone of a sandy beach and evaluate factors that can increase the variability in data sets. The abundance of pellets was estimated during twelve consecutive tidal cycles, identifying the position of the high tide between cycles and sampling drift-lines across the intertidal zone. We demonstrate that beach dynamic processes such as the overlap of strandlines and artefacts of the methods can increase the small-scale variability. The results obtained are discussed in terms of the methodological considerations needed to understand the distribution of pellets in the beach environment, with special implications for studies focused on patterns of input. Copyright © 2015 Elsevier Ltd. All rights reserved.

Existence, regularity, and concentration phenomenon of nontrivial solitary waves for a class of generalized variable coefficient Kadomtsev-Petviashvili equation

NASA Astrophysics Data System (ADS)

Alves, Claudianor O.; Miyagaki, Olímpio H.

2017-08-01

In this paper, we establish some results concerning the existence, regularity, and concentration phenomenon of nontrivial solitary waves for a class of generalized variable coefficient Kadomtsev-Petviashvili equation. Variational methods are used to get an existence result, as well as, to study the concentration phenomenon, while the regularity is more delicate because we are leading with functions in an anisotropic Sobolev space.

Alternative Aviation Jet Fuel Sustainability Evaluation Report Task 1 : Report Evaluating Existing Sustainability Evaluation Programs

DOT National Transportation Integrated Search

2011-10-25

This report describes how existing biofuel sustainability evaluation programs meet requirements that are under consideration or are in early phases of adoption and implementation in various US and international contexts. Biofuel sustainability evalua...

Simulating the Stability of Colloidal Amorphous Iron Oxide in Natural Water

EPA Science Inventory

Considerable uncertainty exists as to whether existing thermodynamic equilibrium solid/water partitioning paradigms can be used to assess the mobility of insoluble manufactured nanomaterials in the aquatic environment. In this work, the traditional Derjaguin–Landau–Verwey–Overbee...

Feasibility study of an aerospace museum in the western United States. Volume 1: Summary, conclusions, and recommendations

NASA Technical Reports Server (NTRS)

1972-01-01

A survey of existing aerospace museums in the U.S. and a study of the feasibility of establishing an aerospace museum in the western U.S. are summarized. It is recommended that prime consideration be given to carefully considered support of development of existing aerospace exhibits rather than establishment of a new major museum. In the event that the decision is made to pursue the establishment of a new museum, Los Angeles is considered to be the most favorable location. In particular, because of the large attendance and existing building space at the California Museum of Science and Industry at Los Angeles, it is recommended that this museum's proposal be given first consideration. Supporting surveys of aerospace museums, funding, and related studies are also summarized.

Geriatric depression and its relation with cognitive impairment and dementia.

PubMed

Dillon, Carol; Tartaglini, María Florencia; Stefani, Dorina; Salgado, Pablo; Taragano, Fernando E; Allegri, Ricardo F

2014-01-01

Different subtypes of depressive syndromes exist in late life; many of them have cognitive impairment and sometimes it is difficult to differentiate them from dementia. This research aimed to investigate subtypes of geriatric depression associated with cognitive impairment, searched for differential variables and tried to propose a study model. A hundred and eighteen depressive patients and forty normal subjects matched by age and educational level were evaluated with an extensive neuropsychological battery, scales to evaluate neuropsychiatric symptoms and daily life activities (DLA). Depressive patients were classified in groups by SCAN 2.1: Major Depression Disorder (MDD) (n: 31), Dysthymia Disorder (DD) (n: 31), Subsyndromal Depression Disorder (SSD) (n: 29), Depression due to Dementia (n: 27) (DdD). Neuropsychological significant differences (p<0.05) were observed between depressive groups, demonstrating distinctive cognitive profiles. Moreover, significant differences (p<0.05) were found in DLA between DdD vs all groups and MDD vs controls and vs SSD. Age of onset varied in the different subtypes of depression. Beck Depression Inventory (BDI) and Mini Mental State Examination (MMSE) were significant variables that helped to differentiate depressive groups. Significant correlations between BDI and Neuropsychological tests were found in MDD and DD groups. Depressive symptoms and its relation with neuropsychological variables, MMSE, cognitive profiles, DLA and age of onset of depression should be taken into consideration for the study of subtypes of geriatric depression. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Energy monitoring in gins

USDA-ARS?s Scientific Manuscript database

Energy costs are the second largest source of variable costs for cotton gins, accounting for 27% of variable costs. Energy use has typically not been a major consideration in gin design, and previous studies of energy use have utilized instantaneous readings or aggregated season-long values. In this...

Consideration of What May Influence Student Outcomes on Alternate Assessment.

ERIC Educational Resources Information Center

Browder, Diane M.; Fallin, Kathy; Davis, Stephanie; Karvonen, Meagan

2003-01-01

This article describes variables that may influence alternate assessment outcomes for students with disabilities and offers recommendations to enhance student achievement. These variables include technical quality, curriculum access, data collection, instructional effectiveness, risk factors, and resources allocated to instruction. Two of four…

Energy Monitoring in Gins - 2011

USDA-ARS?s Scientific Manuscript database

Energy costs are the second largest source of variable costs for gins, accounting for 27% of variable costs. Energy use has typically not been a major consideration in gin design and previous studies of energy use have utilized instantaneous readings or aggregated season-long values. Electricity u...

Electricity use patterns in cotton gins

USDA-ARS?s Scientific Manuscript database

Energy costs are the second largest source of variable costs for cotton gins, with electricity accounting for 18% of variable costs. Energy use has typically not been a major consideration in gin design and previous studies of energy use have utilized instantaneous readings or aggregated season-lon...

Environmental criteria for human comfort. A study of the related literature

NASA Technical Reports Server (NTRS)

Jacobson, I. D.

1974-01-01

The data presented has for the most part been extracted from existing in-house and memoranda reports. The variables considered are motion, noise, temperature and pressure. The report is broken down into chapters for each of the environmental variables and criteria proposed based on the existing literature.

Manufacture of threads with variable pitch by using noncircular gears

NASA Astrophysics Data System (ADS)

Slătineanu, L.; Dodun, O.; Coteață, M.; Coman, I.; Nagîț, G.; Beșliu, I.

2016-08-01

There are mechanical equipments in which shafts threaded with variable pitch are included. Such a shaft could be met in the case of worm specific to the double enveloping worm gearing. Over the years, the researchers investigated some possibilities to geometrically define and manufacture the shaft zones characterized by a variable pitch. One of the methods able to facilitate the manufacture of threads with variable pitch is based on the use of noncircular gears in the threading kinematic chain for threading by cutting. In order to design the noncircular gears, the mathematical law of pitch variation has to be known. An analysis of pitch variation based on geometrical considerations was developed in the case of a double enveloping globoid worm. Subsequently, on the bases of a proper situation, a numerical model was determined. In this way, an approximately law of pitch variation was determined and it could be taken into consideration when designing the noncircular gears included in the kinematic chain of the cutting machine tool.

Numerical simulation of velocity and temperature fields in natural circulation loop

NASA Astrophysics Data System (ADS)

Sukomel, L. A.; Kaban'kov, O. N.

2017-11-01

Low flow natural circulation regimes are realized in many practical applications and the existence of the reliable engineering and design calculation methods of flows driven exclusively by buoyancy forces is an actual problem. In particular it is important for the analysis of start up regimes of passive safety systems of nuclear power plants. In spite of a long year investigations of natural circulation loops no suitable predicting recommendations for heat transfer and friction for the above regimes have been proposed for engineering practice and correlations for forced flow are commonly used which considerably overpredicts the real flow velocities. The 2D numerical simulation of velocity and temperature fields in circular tubes for laminar flow natural circulation with reference to the laboratory experimental loop has been carried out. The results were compared with the 1D modified model and experimental data obtained on the above loop. The 1D modified model was still based on forced flow correlations, but in these correlations the physical properties variability and the existence of thermal and hydrodynamic entrance regions are taken into account. The comparison of 2D simulation, 1D model calculations and the experimental data showed that even subject to influence of liquid properties variability and entrance regions on heat transfer and friction the use of 1D model with forced flow correlations do not improve the accuracy of calculations. In general, according to 2D numerical simulation the wall shear stresses are mainly affected by the change of wall velocity gradient due to practically continuous velocity profiles deformation along the whole heated zone. The form of velocity profiles and the extent of their deformation in its turn depend upon the wall heat flux density and the hydraulic diameter.

An Evolutionary-Based Framework for Analyzing Mold and Dampness-Associated Symptoms in DMHS

PubMed Central

Daschner, Alvaro

2017-01-01

Among potential environmental harmful factors, fungi deserve special consideration. Their intrinsic ability to actively germinate or infect host tissues might determine a prominent trigger in host defense mechanisms. With the appearance of fungi in evolutionary history, other organisms had to evolve strategies to recognize and cope with them. Existing controversies around dampness and mold hypersensitivity syndrome (DMHS) can be due to the great variability of clinical symptoms but also of possible eliciting factors associated with mold and dampness. An hypothesis is presented, where an evolutionary analysis of the different response patterns seen in DMHS is able to explain the existing variability of disease patterns. Classical interpretation of immune responses and symptoms are addressed within the field of pathophysiology. The presented evolutionary analysis seeks for the ultimate causes of the vast array of symptoms in DMHS. Symptoms can be interpreted as induced by direct (toxic) actions of spores, mycotoxins, or other fungal metabolites, or on the other side by the host-initiated response, which aims to counterbalance and fight off potentially deleterious effects or fungal infection. Further, individual susceptibility of immune reactions can confer an exaggerated response, and magnified symptoms are then explained in terms of immunopathology. IgE-mediated allergy fits well in this scenario, where individuals with an atopic predisposition suffer from an exaggerated response to mold exposure, but studies addressing why such responses have evolved and if they could be advantageous are scarce. Human history is plenty of plagues and diseases connected with mold exposure, which could explain vulnerability to mold allergy. Likewise, multiorgan symptoms in DMHS are analyzed for its possible adaptive role not only in the defense of an active infection, but also as evolved mechanisms for avoidance of potentially harmful environments in an evolutionary past or present setting. PMID:28119688

An Evolutionary-Based Framework for Analyzing Mold and Dampness-Associated Symptoms in DMHS.

PubMed

Daschner, Alvaro

2016-01-01

Among potential environmental harmful factors, fungi deserve special consideration. Their intrinsic ability to actively germinate or infect host tissues might determine a prominent trigger in host defense mechanisms. With the appearance of fungi in evolutionary history, other organisms had to evolve strategies to recognize and cope with them. Existing controversies around dampness and mold hypersensitivity syndrome (DMHS) can be due to the great variability of clinical symptoms but also of possible eliciting factors associated with mold and dampness. An hypothesis is presented, where an evolutionary analysis of the different response patterns seen in DMHS is able to explain the existing variability of disease patterns. Classical interpretation of immune responses and symptoms are addressed within the field of pathophysiology. The presented evolutionary analysis seeks for the ultimate causes of the vast array of symptoms in DMHS. Symptoms can be interpreted as induced by direct (toxic) actions of spores, mycotoxins, or other fungal metabolites, or on the other side by the host-initiated response, which aims to counterbalance and fight off potentially deleterious effects or fungal infection. Further, individual susceptibility of immune reactions can confer an exaggerated response, and magnified symptoms are then explained in terms of immunopathology. IgE-mediated allergy fits well in this scenario, where individuals with an atopic predisposition suffer from an exaggerated response to mold exposure, but studies addressing why such responses have evolved and if they could be advantageous are scarce. Human history is plenty of plagues and diseases connected with mold exposure, which could explain vulnerability to mold allergy. Likewise, multiorgan symptoms in DMHS are analyzed for its possible adaptive role not only in the defense of an active infection, but also as evolved mechanisms for avoidance of potentially harmful environments in an evolutionary past or present setting.

Instructional Design Considerations in Converting Non-CBT Materials into CBT Courses.

ERIC Educational Resources Information Center

Ng, Raymond

Instructional designers who are asked to convert existing training materials into computer-based training (CBT) must take special precautions to avoid making the product into a sophisticated page turner. Although conversion may save considerable time on subject research and analysis, courses to be delivered through microcomputers may require…

32 CFR Enclosure 1 to Part 187 - Requirements for Environmental Considerations-Global Commons

Code of Federal Regulations, 2014 CFR

2014-07-01

... environment of the global commons, an environmental impact statement, as described below, will be prepared to... duplication. If an environmental impact statement for a particular action already exists, regardless of what... implementation, or subject matter. 6. Tiering. Consideration should be given to tiering of environmental impact...

32 CFR Enclosure 1 to Part 187 - Requirements for Environmental Considerations-Global Commons

Code of Federal Regulations, 2013 CFR

2013-07-01

... environment of the global commons, an environmental impact statement, as described below, will be prepared to... duplication. If an environmental impact statement for a particular action already exists, regardless of what... implementation, or subject matter. 6. Tiering. Consideration should be given to tiering of environmental impact...

Considerations Before Writing a Public Library Building Program in Children's Services.

ERIC Educational Resources Information Center

Hektoen, Faith

Designed to be useful for the assessment of existing collections and facilities as well as for planning new libraries, these guidelines detail specific needs, considerations and possibilities, and specifications for both materials and area planning. The materials section includes separate treatment for various types of books and other…

Subsonic leaky Rayleigh waves at liquid-solid interfaces.

PubMed

Mozhaev, V G; Weihnacht, M

2002-05-01

The paper is devoted to the study of leaky Rayleigh waves at liquid-solid interfaces close to the border of the existence domain of these modes. The real and complex roots of the secular equation are computed for interface waves at the boundary between water and a binary isotropic alloy of gold and silver with continuously variable composition. The change of composition of the alloy allows one to cross a critical velocity for the existence of leaky waves. It is shown that, contrary to popular opinion, the critical velocity does not coincide with the phase velocity of bulk waves in liquid. The true threshold velocity is found to be smaller, the correction being of about 1.45%. Attention is also drawn to the fact that using the real part of the complex phase velocity as a velocity of leaky waves gives only approximate value. The most interesting feature of the waves under consideration is the presence of energy leakage in the subsonic range of the phase velocities where, at first glance, any radiation by harmonic waves is not permitted. A simple physical explanation of this radiation with due regard for inhomogeneity of radiated and radiating waves is given. The controversial question of the existence of leaky Rayleigh waves at a water/ice interface is reexamined. It is shown that the solution considered previously as a leaky wave is in fact the solution of the bulk-wave-reflection problem for inhomogeneous waves.

The Semistructured Interview for Consideration of Ethnic Culture in Therapy Scale: Initial Psychometric and Outcome Support

ERIC Educational Resources Information Center

Donohue, Brad; Strada, Marilyn J.; Rosales, Rocio; Taylor-Caldwell, Aundrea; Hise, Dortha; Ahman, Sarah; Lefforge, Noelle L.; Kopof, Monique; Devore, Greg; Soares, Bruno; Radkovich, Ben; Laino, Rowena

2006-01-01

There has been recent pressure for practitioners to consider cultural variables when implementing evidence-based interventions. Therefore, the Semistructured Interview for Consideration of Ethnic Culture in Therapy Scale (SSICECTS) was empirically developed to address this issue. First, psychometric properties of a 6-item scale were evaluated in…

New variables for classical and quantum gravity

NASA Technical Reports Server (NTRS)

Ashtekar, Abhay

1986-01-01

A Hamiltonian formulation of general relativity based on certain spinorial variables is introduced. These variables simplify the constraints of general relativity considerably and enable one to imbed the constraint surface in the phase space of Einstein's theory into that of Yang-Mills theory. The imbedding suggests new ways of attacking a number of problems in both classical and quantum gravity. Some illustrative applications are discussed.

Considerations when using variable frequency drive technology for pond aquculture

USDA-ARS?s Scientific Manuscript database

Some farmers have decided to use variable frequency drives (VFDs) to control pump speed and water flow rate to reduce operational cost and costs associated with repairs and maintenance. Mixed performance issues with VFDs and electric motors have been reported. Examples include frequent drive failure...

Some Methodological Considerations in Researching the Family Career.

ERIC Educational Resources Information Center

White, James

Methodological issues which confront researchers using the concept of the family career include the selection of appropriate dependent variables; the efficacy of historical versus immediate effects; and scaling the family career (a proposed replacement for the "family life cycle"). The issue of which dependent variables should be…

Parameter sensitivity and identifiability for a biogeochemical model of hypoxia in the northern Gulf of Mexico

EPA Science Inventory

Local sensitivity analyses and identifiable parameter subsets were used to describe numerical constraints of a hypoxia model for bottom waters of the northern Gulf of Mexico. The sensitivity of state variables differed considerably with parameter changes, although most variables ...

A UNIFORM VERSUS AN AGGREGATED WATER BALANCE OF A SEMI-ARID WATERSHED. (R824784)

EPA Science Inventory

Hydrologists have long struggled with the problem of how to account for the effects of spatial variability in precipitation, vegetation and soils. This problem is particularly acute in snow-fed, semi-arid watersheds, which typically have considerable variability in snow distribut...

Characterizing Temperature Variability and Associated Large Scale Meteorological Patterns Across South America

NASA Astrophysics Data System (ADS)

Detzer, J.; Loikith, P. C.; Mechoso, C. R.; Barkhordarian, A.; Lee, H.

2017-12-01

South America's climate varies considerably owing to its large geographic range and diverse topographical features. Spanning the tropics to the mid-latitudes and from high peaks to tropical rainforest, the continent experiences an array of climate and weather patterns. Due to this considerable spatial extent, assessing temperature variability at the continent scale is particularly challenging. It is well documented in the literature that temperatures have been increasing across portions of South America in recent decades, and while there have been many studies that have focused on precipitation variability and change, temperature has received less scientific attention. Therefore, a more thorough understanding of the drivers of temperature variability is critical for interpreting future change. First, k-means cluster analysis is used to identify four primary modes of temperature variability across the continent, stratified by season. Next, composites of large scale meteorological patterns (LSMPs) are calculated for months assigned to each cluster. Initial results suggest that LSMPs, defined using meteorological variables such as sea level pressure (SLP), geopotential height, and wind, are able to identify synoptic scale mechanisms important for driving temperature variability at the monthly scale. Some LSMPs indicate a relationship with known recurrent modes of climate variability. For example, composites of geopotential height suggest that the Southern Annular Mode is an important, but not necessarily dominant, component of temperature variability over southern South America. This work will be extended to assess the drivers of temperature extremes across South America.

The summer North Atlantic Oscillation (SNAO) variability on decadal to paleoclimate time scales

NASA Astrophysics Data System (ADS)

Linderholm, H. W.; Folland, C. K.; Zhang, P.; Gunnarson, B. E.; Jeong, J. H.; Ren, H.

2017-12-01

The summer North Atlantic Oscillation (SNAO), strongly related to the latitude of the North Atlantic and European summer storm tracks, exerts a considerable influence on European summer climate variability and extremes. Here we extend the period covered by the SNAO from July and August to June, July and August (JJA). As well as marked interannual variability, the JJA SNAO has shown a large inter-decadal change since the 1970s. Decadally averaged, there has been a change from a very positive to a rather negative SNAO phase. This change in SNAO phase is opposite in sign from that expected by a number of climate models under enhanced greenhouse forcing by the late twenty first century. It has led to noticeably wetter summers in North West Europe in the last decade. On interannual to multidecadal timescales, SNAO variability is linked to variations in North Atlantic sea surface temperature (SST): observations and models indicate an association between the Atlantic Multi-decadal Oscillation (AMO) where the cold (warm) phase of the AMO corresponds a positive (negative) phase of the SNAO. Observations also indicate a link with SST in the Gulf Stream region of the North Atlantic where, particularly on decadal time scales, SST warming may favour a more positive phase of the SNAO. Influences of Arctic climate change on North Atlantic and European atmospheric circulation may also exist, particularly reduced sea ice coverage, perhaps favouring the negative phase of the SNAO. A new tree-ring data based JJA SNAO reconstruction extending over the last millennium, as well as climate model output for the same period, enables us to examine the influence of North Atlantic SST and Arctic sea-ice coverage, as well as SNAO impacts on European summer climate, in a long-term, pre-industrial context.

A taxonomy of state public health preparedness units: an empirical examination of organizational structure.

PubMed

Menachemi, Nir; Yeager, Valerie A; Duncan, W Jack; Katholi, Charles R; Ginter, Peter M

2012-01-01

State public health preparedness units (SPHPUs) were developed in response to federal funding to improve response to disasters: a responsibility that had not traditionally been within the purview of public health. The SPHPUs were created within the existing public health organizational structure, and their placement may have implications for how the unit functions, how communication takes place, and ultimately how well the key responsibilities are performed. This study empirically identifies a taxonomy of similarly structured SPHPUs and examines whether this structure is associated with state geographic, demographic, and threat-vulnerability characteristics. Data representing each SPHPU were extracted from publically available sources, including organizational charts and emergency preparedness plans for 2009. A cross-sectional segmentation analysis was conducted of variables representing structural attributes. Fifty state public health departments. Variables representing "span of control" and "hierarchal levels" were extracted from organizational charts. Structural "complexity" and "centralization" were extracted from state emergency preparedness documents and other secondary sources. On average, 6.6 people report to the same manager as the SPHPU director; 2.1 levels separate the SPHPU director from the state health officer; and a mean of 13.5 agencies collaborate with SPHPU during a disaster. Despite considerable variability in how SPHPUs had been structured, results of the cluster and principal component analysis identified 7 similarly structured groups. Neither the taxonomic groups nor the individual variables representing structure were found to be associated with state characteristics, including threat vulnerabilities. Our finding supports the hypothesis that SPHPUs are seemingly inadvertently (eg, not strategically) organized. This taxonomy provides the basis for which future research can examine how SPHPU structure relates to performance measures and preparedness strategies.

Assessing the Role of Climate Variability on Liver Fluke Risk in the UK Through Mechanistic Hydro-Epidemiological Modelling

NASA Astrophysics Data System (ADS)

Beltrame, L.; Dunne, T.; Rose, H.; Walker, J.; Morgan, E.; Vickerman, P.; Wagener, T.

2016-12-01

Liver fluke is a flatworm parasite infecting grazing animals worldwide. In the UK, it causes considerable production losses to cattle and sheep industries and costs farmers millions of pounds each year due to reduced growth rates and lower milk yields. Large part of the parasite life-cycle takes place outside of the host, with its survival and development strongly controlled by climatic and hydrologic conditions. Evidence of climate-driven changes in the distribution and seasonality of fluke disease already exists, as the infection is increasingly expanding to new areas and becoming a year-round problem. Therefore, it is crucial to assess current and potential future impacts of climate variability on the disease to guide interventions at the farm scale and mitigate risk. Climate-based fluke risk models have been available since the 1950s, however, they are based on empirical relationships derived between historical climate and incidence data, and thus are unlikely to be robust for simulating risk under changing conditions. Moreover, they are not dynamic, but estimate risk over large regions in the UK based on monthly average climate conditions, so they do not allow investigating the effects of climate variability for supporting farmers' decisions. In this study, we introduce a mechanistic model for fluke, which represents habitat suitability for disease development at 25m resolution with a daily time step, explicitly linking the parasite life-cycle to key hydro-climate conditions. The model is used on a case study in the UK and sensitivity analysis is performed to better understand the role of climate variability on the space-time dynamics of the disease, while explicitly accounting for uncertainties. Comparisons are presented with experts' knowledge and a widely used empirical model.

Assessing national provision of care: variability in bariatric clinical care pathways.

PubMed

Telem, Dana A; Majid, Saniea F; Powers, Kinga; DeMaria, Eric; Morton, John; Jones, Daniel B

2017-02-01

The American Society for Metabolic and Bariatric Surgery (ASMBS) Quality Improvement and Patient Safety (QIPS) Committee hypothesized that collecting and sharing clinical pathways could provide a valuable resource to new and existing bariatric programs. To shed light on the variability in practice patterns across the country by analyzing pathways. United States Centers of Excellence METHODS: From June 2014 to April 2015, clinical pathways pertaining to preoperative, intraoperative, and postoperative management of bariatric patients were solicited from the ASMBS executive council (EC), QIPS committee members, and state chapter presidents. Pathways were de-identified and then analyzed based on predetermined metrics pertaining to preoperative, intraoperative, and postoperative care. Concordance and discordance were then analyzed. In total, 31 pathways were collected; response rate was 80% from the EC, 77% from the QIPS committee, and 21% from state chapter presidents. The number of pathways sent in ranged from 1 to 10 with a median of 3 pathways per individual or institution. The majority of pathways centered on perioperative care (80%). Binary assessment (presence or absence) of variables found a high concordance (defined by greater than 65% of pathways accounting for that parameter) in only 6 variables: nutritional evaluation, psychological evaluation, intraoperative venous thromboembolism (VTE) prophylaxis, utilization of antiemetics in the postoperative period, a dedicated pain pathway, and postoperative laboratory evaluation. There is considerable national variation in clinical pathways among practicing bariatric surgeons. Most pathways center on Metabolic and Bariatric Surgery Accredited Quality Improvement Program (MBSAQIP) accreditation parameters, patient satisfaction, or Surgical Care Improvement Protocol (SCIP) measures. These pathways provide a path toward standardization of improved care. Copyright © 2016. Published by Elsevier Inc.

Anabolic Heterogeneity Following Resistance Training: A Role for Circadian Rhythm?

PubMed

Camera, Donny M

2018-01-01

It is now well established that resistance exercise stimulates muscle protein synthesis and promotes gains in muscle mass and strength. However, considerable variability exists following standardized resistance training programs in the magnitude of muscle cross-sectional area and strength responses from one individual to another. Several studies have recently posited that alterations in satellite cell population, myogenic gene expression and microRNAs may contribute to individual variability in anabolic adaptation. One emerging factor that may also explain the variability in responses to resistance exercise is circadian rhythms and underlying molecular clock signals. The molecular clock is found in most cells within the body, including skeletal muscle, and principally functions to optimize the timing of specific cellular events around a 24 h cycle. Accumulating evidence investigating the skeletal muscle molecular clock indicates that exercise-induced contraction and its timing may regulate gene expression and protein synthesis responses which, over time, can influence and modulate key physiological responses such as muscle hypertrophy and increased strength. Therefore, the circadian clock may play a key role in the heterogeneous anabolic responses with resistance exercise. The central aim of this Hypothesis and Theory is to discuss and propose the potential interplay between the circadian molecular clock and established molecular mechanisms mediating muscle anabolic responses with resistance training. This article begins with a current review of the mechanisms associated with the heterogeneity in muscle anabolism with resistance training before introducing the molecular pathways regulating circadian function in skeletal muscle. Recent work showing members of the core molecular clock system can regulate myogenic and translational signaling pathways is also discussed, forming the basis for a possible role of the circadian clock in the variable anabolic responses with resistance exercise.

Considerations for SphygmoCor radial artery pulse wave analysis: side selection and peripheral arterial blood pressure calibration.

PubMed

Martin, Jeffrey S; Borges, Alexandra R; Christy, John B; Beck, Darren T

2015-10-01

Methods employed for pulse wave analysis (PWA) and peripheral blood pressure (PBP) calibration vary. The purpose of this study was to evaluate the agreement of SphygmoCor PWA parameters derived from radial artery tonometry when considering (1) timing (before vs. after tonometry) and side selection (ipsilateral vs. contralateral limb) for PBP calibration and (2) side selection for tonometry (left vs. right arm). In 34 subjects (aged 21.9 ± 2.3 years), bilateral radial artery tonometry was performed simultaneously on three instances. PBP assessment via oscillometric sphygmomanometry in the left arm only and both arms simultaneously occurred following the first and second instances of tonometry, respectively. Significant within arm differences in PWA parameters derived before and after PBP measurement were observed in the right arm only (for example, aortic systolic blood pressure, Δ=0.38 ± 0.64 mm Hg). Simultaneously captured bilateral PWA variables demonstrated significant between arm differences in 88% (14/16) and 56% (9/16) of outcome variables when calibrated to within arm and equivalent PBP, respectively. Moreover, the right arm consistently demonstrated lower values for clinical PWA variables (for example, augmentation index, bias=-2.79%). However, 26% (n=9) of participants presented with clinically significant differences (>10 mm Hg) in bilateral PBP and their exclusion from analysis abolished most between arm differences observed. SphygmoCor PWA in the right radial artery results in greater variability independent of the timing of PBP measurement and magnitude of calibration pressures in young subjects. Moreover, bilateral PBP measurement is imperative to identify subjects in whom a significant difference in bilateral PWA outcomes may exist.

Adult Bronchoscopy Training

PubMed Central

Wahidi, Momen M.; Read, Charles A.; Buckley, John D.; Addrizzo-Harris, Doreen J.; Shah, Pallav L.; Herth, Felix J. F.; de Hoyos Parra, Alberto; Ornelas, Joseph; Yarmus, Lonny; Silvestri, Gerard A.

2015-01-01

BACKGROUND: The determination of competency of trainees in programs performing bronchoscopy is quite variable. Some programs provide didactic lectures with hands-on supervision, other programs incorporate advanced simulation centers, whereas others have a checklist approach. Although no single method has been proven best, the variability alone suggests that outcomes are variable. Program directors and certifying bodies need guidance to create standards for training programs. Little well-developed literature on the topic exists. METHODS: To provide credible and trustworthy guidance, rigorous methodology has been applied to create this bronchoscopy consensus training statement. All panelists were vetted and approved by the CHEST Guidelines Oversight Committee. Each topic group drafted questions in a PICO (population, intervention, comparator, outcome) format. MEDLINE data through PubMed and the Cochrane Library were systematically searched. Manual searches also supplemented the searches. All gathered references were screened for consideration based on inclusion criteria, and all statements were designated as an Ungraded Consensus-Based Statement. RESULTS: We suggest that professional societies move from a volume-based certification system to skill acquisition and knowledge-based competency assessment for trainees. Bronchoscopy training programs should incorporate multiple tools, including simulation. We suggest that ongoing quality and process improvement systems be introduced and that certifying agencies move from a volume-based certification system to skill acquisition and knowledge-based competency assessment for trainees. We also suggest that assessment of skill maintenance and improvement in practice be evaluated regularly with ongoing quality and process improvement systems after initial skill acquisition. CONCLUSIONS: The current methods used for bronchoscopy competency in training programs are variable. We suggest that professional societies and certifying agencies move from a volume- based certification system to a standardized skill acquisition and knowledge-based competency assessment for pulmonary and thoracic surgery trainees. PMID:25674901

Ability of independently ambulant children with cerebral palsy to ride a two-wheel bicycle: a case-control study.

PubMed

Toovey, Rachel; Reid, Susan M; Rawicki, Barry; Harvey, Adrienne R; Watt, Kerrianne

2017-04-01

Limited information exists on the ability of children with cerebral palsy (CP) to ride a two-wheel bicycle, an activity that may improve health and participation. We aimed to describe bicycle-riding ability and variables associated with ability to ride in children with CP (Gross Motor Functional Classification System [GMFCS] levels I-II) compared with children with typical development. This case-control study surveyed parents of 114 children with CP and 87 children with typical development aged 6 to 15 years (115 males, mean age 9y 11mo, standard deviation [SD] 2y 10mo). Kaplan-Meier methods were used to compare proportions able to ride at any given age between the two groups. Logistic regression was used to assess variables associated with ability to ride for children with CP and typical development separately. The proportion of children with CP able to ride at each level of bicycle-riding ability was substantially lower at each age than peers with typical development (p<0.001). While most children with typical development were able to ride independently by 10 years of age, 51% of children with CP classified as GMFCS level I and 3% of those classified as GMFCS level II had obtained independent riding in the community by 15 years of age. Variables associated with ability to ride for children classified as GMFCS level I were age and parent-rated importance of their child being able to ride. Some independently ambulant children with CP can learn to ride a bicycle, in particular if they are classified as GMFCS level I. Variables associated with ability to ride deserve consideration in shaping future efforts for the majority of this population who are not yet able to ride. © 2016 Mac Keith Press.

Bovid ecomorphology and hominin paleoenvironments of the Shungura Formation, lower Omo River Valley, Ethiopia.

PubMed

Plummer, Thomas W; Ferraro, Joseph V; Louys, Julien; Hertel, Fritz; Alemseged, Zeresenay; Bobe, René; Bishop, L C

2015-11-01

The Shungura Formation in the lower Omo River Valley, southern Ethiopia, has yielded an important paleontological and archeological record from the Pliocene and Pleistocene of eastern Africa. Fossils are common throughout the sequence and provide evidence of paleoenvironments and environmental change through time. This study developed discriminant function ecomorphology models that linked astragalus morphology to broadly defined habitat categories (open, light cover, heavy cover, forest, and wetlands) using modern bovids of known ecology. These models used seven variables suitable for use on fragmentary fossils and had overall classification success rates of >82%. Four hundred and one fossils were analyzed from Shungura Formation members B through G (3.4-1.9 million years ago). Analysis by member documented the full range of ecomorph categories, demonstrating that a wide range of habitats existed along the axis of the paleo-Omo River. Heavy cover ecomorphs, reflecting habitats such as woodland and heavy bushland, were the most common in the fossil sample. The trend of increasing open cover habitats from Members C through F suggested by other paleoenvironmental proxies was documented by the increase in open habitat ecomorphs during this interval. However, finer grained analysis demonstrated considerable variability in ecomorph frequencies over time, suggesting that substantial short-term variability is masked when grouping samples by member. The hominin genera Australopithecus, Homo, and Paranthropus are associated with a range of ecomorphs, indicating that all three genera were living in temporally variable and heterogeneous landscapes. Australopithecus finds were predominantly associated with lower frequencies of open habitat ecomorphs, and high frequencies of heavy cover ecomorphs, perhaps indicating a more woodland focus for this genus. Copyright © 2015 Elsevier Ltd. All rights reserved.

A Literature Survey and Experimental Evaluation of the State-of-the-Art in Uplift Modeling: A Stepping Stone Toward the Development of Prescriptive Analytics.

PubMed

Devriendt, Floris; Moldovan, Darie; Verbeke, Wouter

2018-03-01

Prescriptive analytics extends on predictive analytics by allowing to estimate an outcome in function of control variables, allowing as such to establish the required level of control variables for realizing a desired outcome. Uplift modeling is at the heart of prescriptive analytics and aims at estimating the net difference in an outcome resulting from a specific action or treatment that is applied. In this article, a structured and detailed literature survey on uplift modeling is provided by identifying and contrasting various groups of approaches. In addition, evaluation metrics for assessing the performance of uplift models are reviewed. An experimental evaluation on four real-world data sets provides further insight into their use. Uplift random forests are found to be consistently among the best performing techniques in terms of the Qini and Gini measures, although considerable variability in performance across the various data sets of the experiments is observed. In addition, uplift models are frequently observed to be unstable and display a strong variability in terms of performance across different folds in the cross-validation experimental setup. This potentially threatens their actual use for business applications. Moreover, it is found that the available evaluation metrics do not provide an intuitively understandable indication of the actual use and performance of a model. Specifically, existing evaluation metrics do not facilitate a comparison of uplift models and predictive models and evaluate performance either at an arbitrary cutoff or over the full spectrum of potential cutoffs. In conclusion, we highlight the instability of uplift models and the need for an application-oriented approach to assess uplift models as prime topics for further research.

Variable styles of rifting expressed in crustal structure across three rift segments of the Gulf of California

NASA Astrophysics Data System (ADS)

Lizarralde, D. D.; Axen, G. J.; Brown, H. E.; Fletcher, J. M.; Fernandez, A. G.; Harding, A. J.; Holbrook, W. S.; Kent, G. M.; Paramo, P.; Sutherland, F. H.; Umhoefer, P. J.

2007-05-01

We present a summary of results from a crustal-scale seismic experiment conducted in the southern Gulf of California. This experiment, the PESCADOR experiment, imaged crustal structure across three rift segments, the Alarcon, Guaymas, and San José del Cabo to Puerto Vallarta (Cabo-PV) segments, using seismic refraction/wide-angle reflection data acquired with airgun sources and recorded by closely spaced (10-15 km) ocean-bottom seismometers (OBSs). The imaged crustal structure reveals a surprisingly large variation in rifting style and magmatism between these segments: the Alarcon segment is a wide rift with apparently little syn-rift magmatism; the Guaymas segment is a narrow, magmatically robust rift; and the Cabo-PV segment is a narrow, magmatically "normal" rift. Our explanation for the observed variability is non-traditional in that we do not invoke mantle temperature, the factor commonly invoked to explain end-member volcanic and non-volcanic rifted margins, as the source of the considerable, though non-end-member variability we observe. Instead, we invoke mantle depletion related to pre-rift arc volcanism to account for observed wide, magma-poor rifting and mantle fertility and possibly the influence of sediments to account for robust rift and post-rift magmatism. These factors may commonly vary over small lateral spatial scales in regions that have transitioned from convergent to extensional tectonics, as is the case for the Gulf of California and many other rifts. Our hypothesis suggests that substantial lateral variability may exist within the uppermost mantle beneath the Gulf of California today, and it is hoped that ongoing efforts to image upper mantle structure here will provide tests for this hypothesis.

Genetic structure of American chestnut populations based on neutral DNA markers

Treesearch

Thomas L. Kubisiak; James H. Roberds

2006-01-01

Microsatellite and RAPD markers suggest that American chestnut exists as a highly variable species. Even at the margins of its natural range, with a large proportion of its genetic variability occurring within populations (~95%). A statistically significant proportion also exists among population. Although genetic differentiation among populations has taken place, no...

Fabric filter model sensitivity analysis. Final report Jun 1978-Feb 1979

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

Dennis, R.; Klemm, H.A.; Battye, W.

1979-04-01

The report gives results of a series of sensitivity tests of a GCA fabric filter model, as a precursor to further laboratory and/or field tests. Preliminary tests had shown good agreement with field data. However, the apparent agreement between predicted and actual values was based on limited comparisons: validation was carried out without regard to optimization of the data inputs selected by the filter users or manufactures. The sensitivity tests involved introducing into the model several hypothetical data inputs that reflect the expected ranges in the principal filter system variables. Such factors as air/cloth ratio, cleaning frequency, amount of cleaning,more » specific resistence coefficient K2, the number of compartments, and inlet concentration were examined in various permutations. A key objective of the tests was to determine the variables that require the greatest accuracy in estimation based on their overall impact on model output. For K2 variations, the system resistance and emission properties showed little change; but the cleaning requirement changed drastically. On the other hand, considerable difference in outlet dust concentration was indicated when the degree of fabric cleaning was varied. To make the findings more useful to persons assessing the probable success of proposed or existing filter systems, much of the data output is presented in graphs or charts.« less

Temporal Changes in Community Resilience to Drought Hazard

NASA Astrophysics Data System (ADS)

Mihunov, V.

2017-12-01

The threat of droughts and their associated impacts on the landscape and human communities have long been recognized. While considerable research on the climatological aspect of droughts has been conducted, studies on the resilience of human communities to the effects of drought remain limited. Understanding how different communities respond to and recover from the drought hazard, i.e. their community resilience, should inform the development of better strategies to cope with the hazard. This research assesses community resilience to drought hazard in South-Central U.S. and captures the temporal changes of community resilience in the region facing the climate change. First, the study applies the Resilience Inference Measurement (RIM) framework using the existing drought incidence, crop damage, socio-economic and food-water-energy nexus variables, which allows to assign county-level resilience scores in the study region and derive variables contributing to the resilience. Second, it captures the temporal changes in community resilience by using the model extracted from the RIM study and socio-economic data from several consecutive time periods. The resilience measurement study should help understand the complex process underlying communities' response to the drought impacts. The results identify gaps in resilience planning and help the improvement of the community resilience to the droughts of increasing frequency and intensity.

Light-driven growth in Amazon evergreen forests explained by seasonal variations of vertical canopy structure.

PubMed

Tang, Hao; Dubayah, Ralph

2017-03-07

Light-regime variability is an important limiting factor constraining tree growth in tropical forests. However, there is considerable debate about whether radiation-induced green-up during the dry season is real, or an apparent artifact of the remote-sensing techniques used to infer seasonal changes in canopy leaf area. Direct and widespread observations of vertical canopy structures that drive radiation regimes have been largely absent. Here we analyze seasonal dynamic patterns between the canopy and understory layers in Amazon evergreen forests using observations of vertical canopy structure from a spaceborne lidar. We discovered that net leaf flushing of the canopy layer mainly occurs in early dry season, and is followed by net abscission in late dry season that coincides with increasing leaf area of the understory layer. Our observations of understory development from lidar either weakly respond to or are not correlated to seasonal variations in precipitation or insolation, but are strongly related to the seasonal structural dynamics of the canopy layer. We hypothesize that understory growth is driven by increased light gaps caused by seasonal variations of the canopy. This light-regime variability that exists in both spatial and temporal domains can better reveal the drought-induced green-up phenomenon, which appears less obvious when treating the Amazon forests as a whole.

No Evidence of the Ego-Depletion Effect across Task Characteristics and Individual Differences: A Pre-Registered Study

PubMed Central

Lurquin, John H.; Michaelson, Laura E.; Barker, Jane E.; Gustavson, Daniel E.; von Bastian, Claudia C.; Carruth, Nicholas P.; Miyake, Akira

2016-01-01

Ego-depletion, a psychological phenomenon in which participants are less able to engage in self-control after prior exertion of self-control, has become widely popular in the scientific community as well as in the media. However, considerable debate exists among researchers as to the nature of the ego-depletion effect, and growing evidence suggests the effect may not be as strong or robust as the extant literature suggests. We examined the robustness of the ego-depletion effect and aimed to maximize the likelihood of detecting the effect by using one of the most widely used depletion tasks (video-viewing attention control task) and by considering task characteristics and individual differences that potentially moderate the effect. We also sought to make our research plan transparent by pre-registering our hypotheses, procedure, and planned analyses prior to data collection. Contrary to the ego-depletion hypothesis, participants in the depletion condition did not perform worse than control participants on the subsequent self-control task, even after considering moderator variables. These findings add to a growing body of evidence suggesting ego-depletion is not a reliable phenomenon, though more research is needed that uses large sample sizes, considers moderator variables, and pre-registers prior to data collection. PMID:26863227

Mappings of Least Dirichlet Energy and their Hopf Differentials

NASA Astrophysics Data System (ADS)

Iwaniec, Tadeusz; Onninen, Jani

2013-08-01

The paper is concerned with mappings {h \\colon {X}} {{begin{array}{ll} onto \\ longrightarrow }} {{Y}} between planar domains having least Dirichlet energy. The existence and uniqueness (up to a conformal change of variables in {{X}}) of the energy-minimal mappings is established within the class {overline{fancyscript{H}}_2({X}, {Y})} of strong limits of homeomorphisms in the Sobolev space {fancyscript{W}^{1,2}({X}, {Y})} , a result of considerable interest in the mathematical models of nonlinear elasticity. The inner variation of the independent variable in {{X}} leads to the Hopf differential {hz overline{h_{bar{z}}} dz ⊗ dz} and its trajectories. For a pair of doubly connected domains, in which {{X}} has finite conformal modulus, we establish the following principle: A mapping {h in overline{fancyscript{H}}2 ({X}, {Y})} is energy-minimal if and only if its Hopf-differential is analytic in {{X}} and real along {partial {X}} . In general, the energy-minimal mappings may not be injective, in which case one observes the occurrence of slits in {{X}} (cognate with cracks). Slits are triggered by points of concavity of {{Y}} . They originate from {partial {X}} and advance along vertical trajectories of the Hopf differential toward {{X}} where they eventually terminate, so no crosscuts are created.

An animated landscape representation of CD4+ T-cell differentiation, variability, and plasticity: Insights into the behavior of populations versus cells

PubMed Central

Rebhahn, Jonathan A; Deng, Nan; Sharma, Gaurav; Livingstone, Alexandra M; Huang, Sui; Mosmann, Tim R

2014-01-01

Recent advances in understanding CD4+ T-cell differentiation suggest that previous models of a few distinct, stable effector phenotypes were too simplistic. Although several well-characterized phenotypes are still recognized, some states display plasticity, and intermediate phenotypes exist. As a framework for reexamining these concepts, we use Waddington's landscape paradigm, augmented with explicit consideration of stochastic variations. Our animation program “LAVA” visualizes T-cell differentiation as cells moving across a landscape of hills and valleys, leading to attractor basins representing stable or semistable differentiation states. The model illustrates several principles, including: (i) cell populations may behave more predictably than individual cells; (ii) analogous to reticulate evolution, differentiation may proceed through a network of interconnected states, rather than a single well-defined pathway; (iii) relatively minor changes in the barriers between attractor basins can change the stability or plasticity of a population; (iv) intrapopulation variability of gene expression may be an important regulator of differentiation, rather than inconsequential noise; (v) the behavior of some populations may be defined mainly by the behavior of outlier cells. While not a quantitative representation of actual differentiation, our model is intended to provoke discussion of T-cell differentiation pathways, particularly highlighting a probabilistic view of transitions between states. PMID:24945794

Long-term monitoring of airborne pollen in Alaska and the Yukon: Possible implications for global change

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

Anderson, J.H.

Airborne pollen and spores have been sampled since 1978 in Fairbanks and 1982 Anchorage and other Alaska-Yukon locations for medical and ecological purposes. Comparative analyses of pre- and post-1986 data subsets reveal that after 1986 (1) pollen is in the air earlier, (2) the multiyear average of degree-days promoting pollen onset is little changed while (3) annual variation in degree-days at onset is greater, (4) pollen and spore annual productions are considerably higher, and (5) there is more year-to-year variation in pollen production. These changes probably reflect directional changes in certain weather variables, and there is some indication that theymore » are of global change significance, i.e., related to increasing atmospheric greenhouse gases. Correlations with pollen data suggest that weather variables of high influence are temperatures during specific periods following pollen dispersal in the preceding year and the average temperature in April of the current year. Annual variations in pollen dispersal might be roughly linked to the 11 year sunspot cycle through air temperature mediators. Weather in 1990, apparent pollen production cycles under endogenous control, and the impending sunspot maximum portend a very severe pollen season in 199 existing but unfunded sampling projects.« less

The potential distribution of Phlebotomus papatasi (Diptera: Psychodidae) in Libya based on ecological niche model.

PubMed

Abdel-Dayem, M S; Annajar, B B; Hanafi, H A; Obenauer, P J

2012-05-01

The increased cases of cutaneous leishmaniasis vectored by Phlebotomus papatasi (Scopoli) in Libya have driven considerable effort to develop a predictive model for the potential geographical distribution of this disease. We collected adult P. papatasi from 17 sites in Musrata and Yefern regions of Libya using four different attraction traps. Our trap results and literature records describing the distribution of P. papatasi were incorporated into a MaxEnt algorithm prediction model that used 22 environmental variables. The model showed a high performance (AUC = 0.992 and 0.990 for training and test data, respectively). High suitability for P. papatasi was predicted to be largely confined to the coast at altitudes <600 m. Regions south of 300 degrees N latitude were calculated as unsuitable for this species. Jackknife analysis identified precipitation as having the most significant predictive power, while temperature and elevation variables were less influential. The National Leishmaniasis Control Program in Libya may find this information useful in their efforts to control zoonotic cutaneous leishmaniasis. Existing records are strongly biased toward a few geographical regions, and therefore, further sand fly collections are warranted that should include documentation of such factors as soil texture and humidity, land cover, and normalized difference vegetation index (NDVI) data to increase the model's predictive power.

No Evidence of the Ego-Depletion Effect across Task Characteristics and Individual Differences: A Pre-Registered Study.

PubMed

Lurquin, John H; Michaelson, Laura E; Barker, Jane E; Gustavson, Daniel E; von Bastian, Claudia C; Carruth, Nicholas P; Miyake, Akira

2016-01-01

Ego-depletion, a psychological phenomenon in which participants are less able to engage in self-control after prior exertion of self-control, has become widely popular in the scientific community as well as in the media. However, considerable debate exists among researchers as to the nature of the ego-depletion effect, and growing evidence suggests the effect may not be as strong or robust as the extant literature suggests. We examined the robustness of the ego-depletion effect and aimed to maximize the likelihood of detecting the effect by using one of the most widely used depletion tasks (video-viewing attention control task) and by considering task characteristics and individual differences that potentially moderate the effect. We also sought to make our research plan transparent by pre-registering our hypotheses, procedure, and planned analyses prior to data collection. Contrary to the ego-depletion hypothesis, participants in the depletion condition did not perform worse than control participants on the subsequent self-control task, even after considering moderator variables. These findings add to a growing body of evidence suggesting ego-depletion is not a reliable phenomenon, though more research is needed that uses large sample sizes, considers moderator variables, and pre-registers prior to data collection.

[Reducing urinary catheter use in patients hospitalized in internal medicine departments].

PubMed

Shimoni, Zvi

2014-07-01

Clinical utility exists in certain situations for introducing a urinary catheter, but its use is the major cause of in-hospitaL acquired urinary tract infections. Furthermore, there are other complications of urinary catheterization, including urethral injury, macroscopic hematuria, and the inability to remove the catheter once introduced. Also, the in-hospital use of an indwelling urinary catheter in the elderly patient is associated with prolonged hospitalizations and an increased risk of in-hospital mortality. Although there are clinical criteria for the use of an indwelling urinary catheter, there is considerable variability in the utilization rates between hospitals and departments. For example, the rates of catheterization in general internal medicine departments usually varies between 8% to 20% and increases with the age of the patients. However, it has been shown that up to 50% of catheterizations are unjustified. Therefore, there are efforts to decrease the rate of use of urinary catheters on the one hand, and to limit the number of days with the indwelling catheter in place on the other hand. These efforts have been partially successful. The root of the problem is that the criteria for catheterization are generally vague, leading to variable interpretations. More precise definitions along with continuous monitoring will likely decrease catheterization rates without putting the patient at risk.

Genomic Diversification of Enterococci in Hosts: The Role of the Mobilome

PubMed Central

Santagati, Maria; Campanile, Floriana; Stefani, Stefania

2012-01-01

Enterococci are ubiquitous lactic acid bacteria, possessing a flexible nature that allows them to colonize various environments and hosts but also to be opportunistic pathogens. Many papers have contributed to a better understanding of: (i) the taxonomy of this complex group of microorganisms; (ii) intra-species variability; (iii) the role of different pathogenicity traits; and (iv) some markers related to the character of host-specificity, but the reasons of such incredible success of adaptability is still far from being fully explained. Recently, genomic-based studies have improved our understanding of the genome diversity of the most studied species, i.e., E. faecalis and E. faecium. From these studies, what is becoming evident is the role of the mobilome in adding new abilities to colonize new hosts and environments, and eventually in driving their evolution: specific clones associated with human infections or specific hosts can exist, but probably the consideration of these populations as strictly clonal groups is only partially correct. The variable presence of mobile genetic elements may, indeed, be one of the factors involved in the evolution of one specific group in a specific host and/or environment. Certainly more extensive studies using new high throughput technologies are mandatory to fully understand the evolution of predominant clones and species in different hosts and environments. PMID:22435066

Genomic diversification of enterococci in hosts: the role of the mobilome.

PubMed

Santagati, Maria; Campanile, Floriana; Stefani, Stefania

2012-01-01

Enterococci are ubiquitous lactic acid bacteria, possessing a flexible nature that allows them to colonize various environments and hosts but also to be opportunistic pathogens. Many papers have contributed to a better understanding of: (i) the taxonomy of this complex group of microorganisms; (ii) intra-species variability; (iii) the role of different pathogenicity traits; and (iv) some markers related to the character of host-specificity, but the reasons of such incredible success of adaptability is still far from being fully explained. Recently, genomic-based studies have improved our understanding of the genome diversity of the most studied species, i.e., E. faecalis and E. faecium. From these studies, what is becoming evident is the role of the mobilome in adding new abilities to colonize new hosts and environments, and eventually in driving their evolution: specific clones associated with human infections or specific hosts can exist, but probably the consideration of these populations as strictly clonal groups is only partially correct. The variable presence of mobile genetic elements may, indeed, be one of the factors involved in the evolution of one specific group in a specific host and/or environment. Certainly more extensive studies using new high throughput technologies are mandatory to fully understand the evolution of predominant clones and species in different hosts and environments.

Things that go bump in the light - On the optical specification of contact severity

NASA Technical Reports Server (NTRS)

Kaiser, Mary K.; Phatak, Anil V.

1993-01-01

Psychologists are intrigued with the idea that optical variables can specify not only the time until an object impacts an observer but also the severity of the impact. However, the mapping between the optical variables and the kinematic variables has been misstated, erroneously implying that there exist critical values of the optical variables used for locomotion and control. In this commentary, the mathematical relationship between the optical and kinematic variables is reexamined and the erroneous assumptions that have led to the proposal of critical values are shown. Also examined are the empirical data on deceleration to approach to assess whether the proposed optical variables are likely candidates for control strategies. Finally, problems associated with numerical approximations to dynamic systems, particularly when analytic solutions exist, are discussed.

Endodontic and Clinical Considerations in the Management of Variable Anatomy in Mandibular Premolars: A Literature Review

PubMed Central

Hammo, Mohammad

2014-01-01

Mandibular premolars are known to have numerous anatomic variations of their roots and root canals, which are a challenge to treat endodontically. The paper reviews literature to detail the various clinically relevant anatomic considerations with detailed techniques and methods to successfully manage these anomalies. An emphasis and detailed description of every step of treatment including preoperative diagnosis, intraoperative identification and management, and surgical endodontic considerations for the successful management of these complex cases have been included. PMID:24895584

An update on vaccines for tuberculosis - there is more to it than just waning of BCG efficacy with time.

PubMed

Romano, Marta; Huygen, Kris

2012-12-01

Apart from better diagnostics and new anti-microbial drugs, an effective vaccine for tuberculosis is urgently needed to halt this poverty-related disease, afflicting millions of people worldwide. After a general introduction on the global threat of tuberculosis, the pros and cons of the existing M. bovis BCG vaccine are discussed. As the correlates of protection against tuberculosis remain largely unknown, new findings in biomarker research are described. Next, an update on the ongoing Phase I and Phase II clinical trials is given. Finally, some of the most promising novel pre-clinical developments using live attenuated vaccines, sub-unit vaccines, prime-boost strategies, and new vaccination routes are discussed. The field has made considerable progress and 12 vaccine candidates have now actually entered Phase I or Phase IIa and IIb clinical trials. It is argued that the variable protection conferred by the existing BCG vaccine against reactivation of latent TB is caused not only by waning of its efficacy with time but also by its weak induction of MHC class I restricted responses. Prime-boost strategies based on the actual BCG vaccine may not be sufficient to overcome this hurdle. The use of plasmid DNA vaccination might offer a solution.

The RFad Method--a new fatigue recovery time assessment for industrial activities.

PubMed

Silva e Santos, Marcello; Vidal, Mario Cesar Rodriguez; Moreira, Sergio Bastos

2012-01-01

This paper presents a study about fatigue recovery time assessment processes in work activities. It came about due to a demand presented by an automotive industry giant, in need of updating existing cycle time sheets and TAKT time parameters. The company decided to hire an Ergonomics Laboratory with ties to a major Brazilian University in order to evaluate current conditions and establish a new method to either calculate recovery times or validate existing assessment criteria, based in the ergonomics evaluation of the work activities. It is clear that there has been evident evolution in the industrial sector in the past two decades. It brought up fast modernization of industrial processes, not only in production but also in terms of management systems. Due to improved computer and robotics systems, combined with overall operational advancements - like the use of lighter hand tools and more effective hoist systems - most work activities have had its physical effort requirements reduced in the past decades. Thus, compensation factors built into production times need to be reviewed in order to avoid unnecessary costs associated to them. By using ergonomics considerations, we prevent simply removing the physical variables built in rest time calculations without taking on account, for example, additional cognitive load represented by the use of more sophisticated pieces of equipment.

Chinese Cultural Collectivism and Work-Related Stress: Implications for Employment Counselors.

ERIC Educational Resources Information Center

Chiu, Randy K.; Kosinski, Frederick A., Jr.

1995-01-01

Employment counselors should take cultural issues into consideration as they provide consultation or counseling services. Stress is influenced by cultural and social variables. Examines the collectivism-individualism construct to measure cultural variables and attempt to explain the differences of some social behaviors between Eastern and Western…

Jury Selection in Child Sex Abuse Trials: A Case Analysis

ERIC Educational Resources Information Center

Cramer, Robert J.; Adams, Desiree D.; Brodsky, Stanley L.

2009-01-01

Child sex abuse cases have been the target of considerable psycho-legal research. The present paper offers an analysis of psychological constructs for jury selection in child sex abuse cases from the defense perspective. The authors specifically delineate general and case-specific jury selection variables. General variables include…

Child Internalizing Symptoms: Contributions of Child Temperament, Maternal Negative Affect, and Family Functioning

ERIC Educational Resources Information Center

Crawford, Nicole A.; Schrock, Matthew; Woodruff-Borden, Janet

2011-01-01

Research has traditionally focused on the role of genetic and environmental variables in the development and maintenance of childhood internalizing disorders. Temperament variables, such as negative affect and effortful control have gained considerable interest within the field of developmental psychopathology. Environmental factors such as…

Counselor-Subject Sex Variables in Systematic Desensitization

ERIC Educational Resources Information Center

Geer, Carol A.; Hurst, James C.

1976-01-01

A Sex of Subject x Sex of Counselor interaction in the desensitization of test anxiety among 44 college students suggested consideration of the sex variable. Results showed significant treatment effects by both male and female counselors and a significant interaction effect by the male counselor with female subjects. (Author)

Higher-Order Factors of Personality: Do They Exist?

PubMed Central

Ashton, Michael C.; Lee, Kibeom; Goldberg, Lewis R.; de Vries, Reinout E.

2010-01-01

Scales that measure the Big Five personality factors are often substantially intercorrelated. These correlations are sometimes interpreted as implying the existence of two higher-order factors of personality. We show that correlations between measures of broad personality factors do not necessarily imply the existence of higher-order factors, and might instead be due to variables that represent same-signed blends of orthogonal factors. Therefore, the hypotheses of higher-order factors and blended variables can only be tested with data on lower-level personality variables that define the personality factors. We compared the higher-order factor model and the blended variable model in three participant samples using the Big Five Aspect Scales, and found better fit for the latter model. In other analyses using the HEXACO Personality Inventory, we identified mutually uncorrelated markers of six personality factors. We conclude that correlations between personality factor scales can be explained without postulating any higher-order dimensions of personality. PMID:19458345

Mathematical issues in eternal inflation

NASA Astrophysics Data System (ADS)

Singh Kohli, Ikjyot; Haslam, Michael C.

2015-04-01

In this paper, we consider the problem of the existence and uniqueness of solutions to the Einstein field equations for a spatially flat Friedmann-Lemaître-Robertson-Walker universe in the context of stochastic eternal inflation, where the stochastic mechanism is modelled by adding a stochastic forcing term representing Gaussian white noise to the Klein-Gordon equation. We show that under these considerations, the Klein-Gordon equation actually becomes a stochastic differential equation. Therefore, the existence and uniqueness of solutions to Einstein’s equations depend on whether the coefficients of this stochastic differential equation obey Lipschitz continuity conditions. We show that for any choice of V(φ ), the Einstein field equations are not globally well-posed, hence, any solution found to these equations is not guaranteed to be unique. Instead, the coefficients are at best locally Lipschitz continuous in the physical state space of the dynamical variables, which only exist up to a finite explosion time. We further perform Feller’s explosion test for an arbitrary power-law inflaton potential and prove that all solutions to the Einstein field equations explode in a finite time with probability one. This implies that the mechanism of stochastic inflation thus considered cannot be described to be eternal, since the very concept of eternal inflation implies that the process continues indefinitely. We therefore argue that stochastic inflation based on a stochastic forcing term would not produce an infinite number of universes in some multiverse ensemble. In general, since the Einstein field equations in both situations are not well-posed, we further conclude that the existence of a multiverse via the stochastic eternal inflation mechanism considered in this paper is still very much an open question that will require much deeper investigation.

A Consideration of the Ethics of Teaching English

ERIC Educational Resources Information Center

Christenbury, Leila

2008-01-01

The consideration of questions of morality and ethics, of right and wrong is not confined to churches and mosques and synagogues; it also exists outside religious frameworks, notably in the schools and in teaching. In this article, the author extends the exploration of ethics into the classroom where virtually all acts of writing, language, and…

Design considerations for community mental health management information systems.

PubMed

Lowe, B H; Sugarman, B

1978-01-01

Many community mental health centers are presently faced with the necessity of implementing a management information system. This article offers guidelines for centers dealing with this situation. Whether a center chooses to adapt an existing system or develop one of its own, careful planning prior to the implementation of the system can help ensure that it will meet the needs of the center and operate successfully. The guidelines are organized into the categories of data considerations, people considerations, and system considerations. The first two categories are of general interest, whereas the last category is more technical in nature.

Withdrawing Versus Withholding Freedoms: Nudging and the Case of Tobacco Control.

PubMed

Schmidt, Andreas T

2016-07-01

Is it a stronger interference with people's freedom to withdraw options they currently have than to withhold similar options they do not have? Drawing on recent theorizing about sociopolitical freedom, this article identifies considerations that often make this the case for public policy. However, when applied to tobacco control, these considerations are shown to give us at best only very weak freedom-based reason to prioritize the status quo. This supports a popular argument for so-called "endgame" tobacco control measures: If we believe that cigarettes would and should be withheld from entering markets in hypothetical scenarios in which they do not yet exist, then we also have reason to seek their abolition in situations, such as ours, in which cigarettes do exist-if necessary by banning their sale. The same considerations are then used to disarm objections that have recently been raised to using nudges in public policy.

Cortical Action Potential Backpropagation Explains Spike Threshold Variability and Rapid-Onset Kinetics

PubMed Central

Yu, Yuguo; Shu, Yousheng; McCormick, David A.

2008-01-01

Neocortical action potential responses in vivo are characterized by considerable threshold variability, and thus timing and rate variability, even under seemingly identical conditions. This finding suggests that cortical ensembles are required for accurate sensorimotor integration and processing. Intracellularly, trial-to-trial variability results not only from variation in synaptic activities, but also in the transformation of these into patterns of action potentials. Through simultaneous axonal and somatic recordings and computational simulations, we demonstrate that the initiation of action potentials in the axon initial segment followed by backpropagation of these spikes throughout the neuron results in a distortion of the relationship between the timing of synaptic and action potential events. In addition, this backpropagation also results in an unusually high rate of rise of membrane potential at the foot of the action potential. The distortion of the relationship between the amplitude time course of synaptic inputs and action potential output caused by spike back-propagation results in the appearance of high spike threshold variability at the level of the soma. At the point of spike initiation, the axon initial segment, threshold variability is considerably less. Our results indicate that spike generation in cortical neurons is largely as expected by Hodgkin—Huxley theory and is more precise than previously thought. PMID:18632930

How Am I Going to Pay for That?!: First-Generation University Students and Their Financial Concerns

ERIC Educational Resources Information Center

Shultz, Judith J. Andrews

2013-01-01

This study examines first-generation research-university students in relation to their financial considerations. It is driven by the question, What is the relationship between first-generation college-student status and financial considerations among research-university students? It explores the impact of such variables as first-generation student…

Source characteristics and design consideration for an iron-free variable-period/polarizing undulator for the UV/VUV range on SPEAR (abstract)

NASA Astrophysics Data System (ADS)

Tatchyn, Roman

1992-01-01

Insertion devices that are tuned by electrical period variation are particularly suited for the design of flexible polarized-light sources [R. Tatchyn, J. Appl. Phys. 65, 4107 (1989); R. Tatchyn and T. Cremer, IEEE Trans. Mag. 26, 3102 (1990)]. Important advantages vis-a-vis mechanical or hybrid variable field designs include: (1) significantly more rapid modulation of both polarization and energy, (2) an inherently larger set of polarization modulation capabilities and (3) polarization/energy modulation at continuously optimized values of K. In this paper we outline some of the general considerations that enter into the design of hysteresis-free variable-period/polarizing undulator structures and present the parameters of a recently-completed prototype design capable of generating intense levels of UV/VUV photon flux on SPEAR running at 3 GeV.

Prisoners as Living Donors: A Vulnerabilities Analysis.

PubMed

Ross, Lainie Friedman; Thistlethwaite, J Richard

2018-01-01

Although national guidelines exist for evaluating the eligibility of potential living donors and for procuring their informed consent, no special protections or considerations exist for potential living donors who are incarcerated. Human research subject protections in the United States are codified in the Federal Regulations, 45 CFR 46, and special protections are given to prisoners. Living donor transplantation has parallels with human subject research in that both activities are performed with the primary goal of benefiting third parties. In this article, we describe what special considerations should be provided to prisoners as potential living donors using a vulnerabilities approach adapted from the human research subject protection literature.

To Remodel or To Build?

ERIC Educational Resources Information Center

Rosenblum, Todd

2009-01-01

The question of remodeling an existing house to make it wheelchair accessible or building a new barrier-free house is a difficult decision. This article presents some initial questions and considerations followed by a list of pros and cons for remodeling an existing house vs. building a new house.

Computer aided modeling of soil mix designs to predict characteristics and properties of stabilized road bases.

DOT National Transportation Integrated Search

2009-07-01

"Considerable data exists for soils that were tested and documented, both for native properties and : properties with pozzolan stabilization. While the data exists there was no database for the Nebraska : Department of Roads to retrieve this data for...

D/H Ratios of Marine Lipids from Santa Barbara Basin Sediments

NASA Astrophysics Data System (ADS)

Li, C.; Sessions, A.; Kinnaman, F.; Valentine, D.

2006-12-01

With the early successful application of compound-specific D/H analyses to reconstructing paleoclimate records, most subsequent research has focused on understanding organic D/H fractionations in terrestrial environments. Thus we still know very little about natural D/H variations in lipids derived from marine organisms, or indeed if any such variations exist. We have therefore conducted an extensive survey of lipid δD values in two sediment cores collected in the Santa Barbara Basin. These data allow us to examine 1) variations between the lipid products of different organisms, 2) down-core variations due to diagenesis, and 3) differences between sediments deposited under oxic or anoxic bottom-water conditions. Our results show that considerable D/H variability between different marine products does exist. δD values of n-alkanes (except n-C35) ranged from -94 to -175 ‰, and exhibit a systematic offset between odd and even carbon numbers. The δD value of n-C35 is anomalous at -220‰. Isotopic compositions of n-alkanols range from -126 to -221 , with a pattern of progressive D depletion with chain length observed for free alcohols. δD values of sterols range from -215 to -309‰, and show no systematic variation with carbon number. However, offsets do exist between the saturated, monounsaturated, and diunsaturated sterols. Sterols as a group are strongly depleted in D relative to the bacterial-derived hopanols (-166 to -232‰), suggesting possible differences in biosynthetic fractionations by bacteria and eukaryotes. Phytol and phytane δD values roughly ranged from -360 to -410‰, while phytanol was systematically enriched at -300 to -340‰. Fatty acids encompassed much greater variability, with dD values ranging from -55 to -270‰. In general, saturated fatty acids are enriched in D relative to their unsaturated analogs, and long-chain (>C24) acids are enriched in D relative to short-chain (

Weather patterns as a downscaling tool - evaluating their skill in stratifying local climate variables

NASA Astrophysics Data System (ADS)

Murawski, Aline; Bürger, Gerd; Vorogushyn, Sergiy; Merz, Bruno

2016-04-01

The use of a weather pattern based approach for downscaling of coarse, gridded atmospheric data, as usually obtained from the output of general circulation models (GCM), allows for investigating the impact of anthropogenic greenhouse gas emissions on fluxes and state variables of the hydrological cycle such as e.g. on runoff in large river catchments. Here we aim at attributing changes in high flows in the Rhine catchment to anthropogenic climate change. Therefore we run an objective classification scheme (simulated annealing and diversified randomisation - SANDRA, available from the cost733 classification software) on ERA20C reanalyses data and apply the established classification to GCMs from the CMIP5 project. After deriving weather pattern time series from GCM runs using forcing from all greenhouse gases (All-Hist) and using natural greenhouse gas forcing only (Nat-Hist), a weather generator will be employed to obtain climate data time series for the hydrological model. The parameters of the weather pattern classification (i.e. spatial extent, number of patterns, classification variables) need to be selected in a way that allows for good stratification of the meteorological variables that are of interest for the hydrological modelling. We evaluate the skill of the classification in stratifying meteorological data using a multi-variable approach. This allows for estimating the stratification skill for all meteorological variables together, not separately as usually done in existing similar work. The advantage of the multi-variable approach is to properly account for situations where e.g. two patterns are associated with similar mean daily temperature, but one pattern is dry while the other one is related to considerable amounts of precipitation. Thus, the separation of these two patterns would not be justified when considering temperature only, but is perfectly reasonable when accounting for precipitation as well. Besides that, the weather patterns derived from reanalyses data should be well represented in the All-Hist GCM runs in terms of e.g. frequency, seasonality, and persistence. In this contribution we show how to select the most appropriate weather pattern classification and how the classes derived from it are reflected in the GCMs.

Context-invariant quasi hidden variable (qHV) modelling of all joint von Neumann measurements for an arbitrary Hilbert space

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

Loubenets, Elena R.

We prove the existence for each Hilbert space of the two new quasi hidden variable (qHV) models, statistically noncontextual and context-invariant, reproducing all the von Neumann joint probabilities via non-negative values of real-valued measures and all the quantum product expectations—via the qHV (classical-like) average of the product of the corresponding random variables. In a context-invariant model, a quantum observable X can be represented by a variety of random variables satisfying the functional condition required in quantum foundations but each of these random variables equivalently models X under all joint von Neumann measurements, regardless of their contexts. The proved existence ofmore » this model negates the general opinion that, in terms of random variables, the Hilbert space description of all the joint von Neumann measurements for dimH≥3 can be reproduced only contextually. The existence of a statistically noncontextual qHV model, in particular, implies that every N-partite quantum state admits a local quasi hidden variable model introduced in Loubenets [J. Math. Phys. 53, 022201 (2012)]. The new results of the present paper point also to the generality of the quasi-classical probability model proposed in Loubenets [J. Phys. A: Math. Theor. 45, 185306 (2012)].« less

Magnetic fields and chiral asymmetry in the early hot universe

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

Sydorenko, Maksym; Shtanov, Yuri; Tomalak, Oleksandr, E-mail: maxsydorenko@gmail.com, E-mail: tomalak@uni-mainz.de, E-mail: shtanov@bitp.kiev.ua

In this paper, we study analytically the process of external generation and subsequent free evolution of the lepton chiral asymmetry and helical magnetic fields in the early hot universe. This process is known to be affected by the Abelian anomaly of the electroweak gauge interactions. As a consequence, chiral asymmetry in the fermion distribution generates magnetic fields of non-zero helicity, and vice versa. We take into account the presence of thermal bath, which serves as a seed for the development of instability in magnetic field in the presence of externally generated lepton chiral asymmetry. The developed helical magnetic field andmore » lepton chiral asymmetry support each other, considerably prolonging their mutual existence, in the process of 'inverse cascade' transferring magnetic-field power from small to large spatial scales. For cosmologically interesting initial conditions, the chiral asymmetry and the energy density of helical magnetic field are shown to evolve by scaling laws, effectively depending on a single combined variable. In this case, the late-time asymptotics of the conformal chiral chemical potential reproduces the universal scaling law previously found in the literature for the system under consideration. This regime is terminated at lower temperatures because of scattering of electrons with chirality change, which exponentially washes out chiral asymmetry. We derive an expression for the termination temperature as a function of the chiral asymmetry and energy density of helical magnetic field.« less

A new gender-specific model for skin autofluorescence risk stratification

PubMed Central

Ahmad, Muhammad S.; Damanhouri, Zoheir A.; Kimhofer, Torben; Mosli, Hala H.; Holmes, Elaine

2015-01-01

Advanced glycation endproducts (AGEs) are believed to play a significant role in the pathophysiology of a variety of diseases including diabetes and cardiovascular diseases. Non-invasive skin autofluorescence (SAF) measurement serves as a proxy for tissue accumulation of AGEs. We assessed reference SAF and skin reflectance (SR) values in a Saudi population (n = 1,999) and evaluated the existing risk stratification scale. The mean SAF of the study cohort was 2.06 (SD = 0.57) arbitrary units (AU), which is considerably higher than the values reported for other populations. We show a previously unreported and significant difference in SAF values between men and women, with median (range) values of 1.77 AU (0.79–4.84 AU) and 2.20 AU (0.75–4.59 AU) respectively (p-value « 0.01). Age, presence of diabetes and BMI were the most influential variables in determining SAF values in men, whilst in female participants, SR was also highly correlated with SAF. Diabetes, hypertension and obesity all showed strong association with SAF, particularly when gender differences were taken into account. We propose an adjusted, gender-specific disease risk stratification scheme for Middle Eastern populations. SAF is a potentially valuable clinical screening tool for cardiovascular risk assessment but risk scores should take gender and ethnicity into consideration for accurate diagnosis. PMID:25974028

Initiation and continuation of smoking in iran: a qualitative content analysis.

PubMed

Ebrahimi, Hossein; Sahebihagh, Mohammad Hasan; Ghofranipour, Fazlollah; Sadegh Tabrizi, Jafar

2014-10-01

Smoking is the cause for many preventable deaths worldwide. The rate of smoking has not increased in Iran in the past two decades, but its increase among adolescents and young adults is a concern. This study investigates the risk factors of initiation and continuation of smoking in Iran using a qualitative approach. This is a qualitative content analysis study conducted on 12 smokers and 6 non-smokers in 4 selected cities in Iran. Data were collected with deep and semi-structured interviews, verbatim transcription and simultaneously coding. Then, they were analyzed through content analysis. Three themes and 16 subcategories emerged. The themes were personal inefficacy with 6 subgroups included inadequate information, low age, curiosity, consideration of smoking not as a major problem, wrong beliefs, and making reasons. Family inefficacy with 4 subgroups included poor authority, lack of reaction, existence of stressors, and history of smoking. Vulnerable social environment with 6 subgroups included poverty, social stressors, magnification of smoking, network of cigarette smoking, smoking as a norm and convenience of access. Recognition of smoking among children, modification of wrong beliefs about smoking, empowerment of the individuals against smoking from the very childhood, consideration of familial stress and crisis, and ultimately, paying attention to the role of social variables will play a major role in prevention of smoking and encouraging individuals to quit smoking.

Magnetic fields and chiral asymmetry in the early hot universe

NASA Astrophysics Data System (ADS)

Sydorenko, Maksym; Tomalak, Oleksandr; Shtanov, Yuri

2016-10-01

In this paper, we study analytically the process of external generation and subsequent free evolution of the lepton chiral asymmetry and helical magnetic fields in the early hot universe. This process is known to be affected by the Abelian anomaly of the electroweak gauge interactions. As a consequence, chiral asymmetry in the fermion distribution generates magnetic fields of non-zero helicity, and vice versa. We take into account the presence of thermal bath, which serves as a seed for the development of instability in magnetic field in the presence of externally generated lepton chiral asymmetry. The developed helical magnetic field and lepton chiral asymmetry support each other, considerably prolonging their mutual existence, in the process of `inverse cascade' transferring magnetic-field power from small to large spatial scales. For cosmologically interesting initial conditions, the chiral asymmetry and the energy density of helical magnetic field are shown to evolve by scaling laws, effectively depending on a single combined variable. In this case, the late-time asymptotics of the conformal chiral chemical potential reproduces the universal scaling law previously found in the literature for the system under consideration. This regime is terminated at lower temperatures because of scattering of electrons with chirality change, which exponentially washes out chiral asymmetry. We derive an expression for the termination temperature as a function of the chiral asymmetry and energy density of helical magnetic field.

Revisiting the assessment of semen viscosity and its relationship to leucocytospermia.

PubMed

Flint, M; du Plessis, S S; Menkveld, R

2014-10-01

With infertility challenges posing an obstacle to many couples, the extension of variables to assess male fertility is an important line of research. At the Reproductive Biology Unit where the study was undertaken, a considerable proportion of male patient's seeking fertility assessment presented with hyperviscous semen samples and elevated concentrations of leucocytes. Despite viscosity being included as part of a routine spermiogram, it raises a considerable amount of concern as it is assessed semiquantitatively. The study was undertaken to evaluate the quantification of semen viscosity in centipoise (cP) and to investigate whether a correlation exists between hyperviscosity and leucocytospermia. A total of 200 semen samples were assessed from a sample cohort of two population groups: 162 male patients undergoing fertility assessment and 38 volunteer donors. Semen viscosity was determined by measuring the filling time of a capillary-loaded Leja chamber and quantifying the viscosity in cP. Leucocytes were identified histochemically with a leucocyte peroxidase test. The viscosity when quantified in cP was significantly higher in the peroxidase positive sample group (9.01 ± 0.49 vs. 7.39 ± 0.23 cP; P < 0.005). The introduction of a more accurate method of quantifying viscosity may possibly help to identify, diagnose and treat patients suffering from leucocytospermia to ultimately enhance their fertility potential. © 2013 Blackwell Verlag GmbH.

Water as consumed and its impact on the consumer--do we understand the variables?

PubMed

Bates, A J

2000-01-01

Water is the most important natural resource in the world, without it life cannot exist. In 1854 a cholera outbreak in London caused 10, 000 deaths and positively linked enteric disease with bacterial contamination of drinking water by sewage pollution. Since then, adequate water hygiene standards and sewage purification have played the most significant role in disease eradication and public health improvements everywhere. Standards for drinking water have become an extensive range of microbiological and chemical parametric values. Which has not increased consumer, if the media is to be believed. Customers rightly expect that the water they drink is safe and wholesome. Standard setting is perceived as a precise science and meaningful to health. Is this justified and do scientists and regulators who derive and set the standards understand the uncertainties in the system? Water is the universal solvent, therefore it will never be pure; it will contain impurities prior to and after treatment. Knowledge of its potential to become contaminated is necessary to understand the epidemiology associated with waterborne contaminants and their effects. Water use patterns vary considerably and affect assumptions based on toxicology derived from laboratory studies under tightly controlled conditions. Consideration must be given to the model systems used to assess toxicity and translate results from the laboratory to the real world, if sensible scientifically-based water quality standards are to be set and achieved cost effectively.

Net2Align: An Algorithm For Pairwise Global Alignment of Biological Networks

PubMed Central

Wadhwab, Gulshan; Upadhyayaa, K. C.

2016-01-01

The amount of data on molecular interactions is growing at an enormous pace, whereas the progress of methods for analysing this data is still lacking behind. Particularly, in the area of comparative analysis of biological networks, where one wishes to explore the similarity between two biological networks, this holds a potential problem. In consideration that the functionality primarily runs at the network level, it advocates the need for robust comparison methods. In this paper, we describe Net2Align, an algorithm for pairwise global alignment that can perform node-to-node correspondences as well as edge-to-edge correspondences into consideration. The uniqueness of our algorithm is in the fact that it is also able to detect the type of interaction, which is essential in case of directed graphs. The existing algorithm is only able to identify the common nodes but not the common edges. Another striking feature of the algorithm is that it is able to remove duplicate entries in case of variable datasets being aligned. This is achieved through creation of a local database which helps exclude duplicate links. In a pervasive computational study on gene regulatory network, we establish that our algorithm surpasses its counterparts in its results. Net2Align has been implemented in Java 7 and the source code is available as supplementary files. PMID:28356678

Prediction of porosity of food materials during drying: Current challenges and directions.

PubMed

Joardder, Mohammad U H; Kumar, C; Karim, M A

2017-07-18

Pore formation in food samples is a common physical phenomenon observed during dehydration processes. The pore evolution during drying significantly affects the physical properties and quality of dried foods. Therefore, it should be taken into consideration when predicting transport processes in the drying sample. Characteristics of pore formation depend on the drying process parameters, product properties and processing time. Understanding the physics of pore formation and evolution during drying will assist in accurately predicting the drying kinetics and quality of food materials. Researchers have been trying to develop mathematical models to describe the pore formation and evolution during drying. In this study, existing porosity models are critically analysed and limitations are identified. Better insight into the factors affecting porosity is provided, and suggestions are proposed to overcome the limitations. These include considerations of process parameters such as glass transition temperature, sample temperature, and variable material properties in the porosity models. Several researchers have proposed models for porosity prediction of food materials during drying. However, these models are either very simplistic or empirical in nature and failed to consider relevant significant factors that influence porosity. In-depth understanding of characteristics of the pore is required for developing a generic model of porosity. A micro-level analysis of pore formation is presented for better understanding, which will help in developing an accurate and generic porosity model.

Prioritizing Wetlands for Waterbirds in a Boom and Bust System: Waterbird Refugia and Breeding in the Murray-Darling Basin.

PubMed

Bino, Gilad; Kingsford, Richard T; Porter, John

2015-01-01

Dryland rivers have considerable flow variability, producing complex ecosystems, processes, and communities of organisms that vary over space and time. They are also among the more vulnerable of the world's ecosystems. A key strategy for conservation of dryland rivers is identifying and maintaining key sites for biodiversity conservation, particularly protecting the quantity and quality of flow and flooding regimes. Extreme variability considerably challenges freshwater conservation planning. We systematically prioritised wetlands for waterbirds (simultaneously for 52 species), across about 13.5% of the Murray-Darling Basin (1,061,469 km2), using a 30-year record of systematic aerial surveys of waterbird populations. Nine key wetlands in this area, primarily lakes, floodplains, and swamps, consistently contributed to a representation target (80%) of total abundances of all 52 waterbird species. The long temporal span of our data included dramatic availability (i.e., booms) and scarcity (i.e., busts) of water, providing a unique opportunity to test prioritisation at extremes of variation. These extremes represented periods when waterbirds were breeding or concentrating on refugia, varying wetland prioritisation. In dry years, important wetlands for waterbirds were riverine and lacustrine (12 wetlands) but this changed in wet years to lacustrine and palustrine (8 wetlands). Such variation in ecosystem condition substantially changes the relative importance of individual wetlands for waterbirds during boom and bust phases. Incorporating this variability is necessary for effective conservation of Murray-Darling Basin waterbirds, with considerable generality for other similarly variable systems around the world.

How well can body size represent effects of the environment on demographic rates? Disentangling correlated explanatory variables.

PubMed

Brooks, Mollie E; Mugabo, Marianne; Rodgers, Gwendolen M; Benton, Timothy G; Ozgul, Arpat

2016-03-01

Demographic rates are shaped by the interaction of past and current environments that individuals in a population experience. Past environments shape individual states via selection and plasticity, and fitness-related traits (e.g. individual size) are commonly used in demographic analyses to represent the effect of past environments on demographic rates. We quantified how well the size of individuals captures the effects of a population's past and current environments on demographic rates in a well-studied experimental system of soil mites. We decomposed these interrelated sources of variation with a novel method of multiple regression that is useful for understanding nonlinear relationships between responses and multicollinear explanatory variables. We graphically present the results using area-proportional Venn diagrams. Our novel method was developed by combining existing methods and expanding upon them. We showed that the strength of size as a proxy for the past environment varied widely among vital rates. For instance, in this organism with an income breeding life history, the environment had more effect on reproduction than individual size, but with substantial overlap indicating that size encompassed some of the effects of the past environment on fecundity. This demonstrates that the strength of size as a proxy for the past environment can vary widely among life-history processes within a species, and this variation should be taken into consideration in trait-based demographic or individual-based approaches that focus on phenotypic traits as state variables. Furthermore, the strength of a proxy will depend on what state variable(s) and what demographic rate is being examined; that is, different measures of body size (e.g. length, volume, mass, fat stores) will be better or worse proxies for various life-history processes. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

HadCM3 Simulations of ENSO behaviour during the Mid-Pliocene Warm Period

NASA Astrophysics Data System (ADS)

Bonham, S. G.; Haywood, A. M.; Lunt, D. J.

2009-04-01

It has been suggested that a permanent El Niño state existed during the mid-Pliocene (ca. 3.3 - 3.0 Ma BP), with a west-to-east temperature gradient in the tropical Pacific considerably weaker than today. This is based upon a number of palaeoceanographic studies which have examined the development of the thermocline and SST gradient in the tropical Pacific over the last five million years. This state is now being referred to as El Padre in recognition of the fact that a mean state warming in EEP SSTs does not necessarily imply the presence of a permanent El Niño. Recent results from mid-Pliocene coupled ocean-atmosphere model simulations have shown clear ENSO variability whilst maintaining the warming in the EEP. This research expands on this study, using the UK Met Office GCM (HadCM3), to examine the behaviour and characteristics of ENSO in two mid-Pliocene simulations (with an open and closed Central American Seaway, CAS) compared with a control pre-industrial run, as well as produce a detailed profile of the mean state climates. The results shown include timescales of ENSO variability across four regions in the Pacific, as well as frequency, EOF and wavelet analysis. We have also looked at the interaction of ENSO with the annual cycle and the onset of ENSO events, and the interdecadal variability in the simulations. The initial timeseries produced have shown a greater variability of ENSO during the closed CAS mid-Pliocene simulation where the system oscillates between events much more frequently than seen in the pre-industrial run. The EOF and wavelet analyses quantify this behaviour, showing that the variability is approximately 15% higher over the central and eastern equatorial Pacific, with a period of oscillation of 2-5 years compared with 4-8 years for the pre-industrial simulation. These results will be compared with those obtained from the second mid-Pliocene simulation (open CAS).

Ecological Momentary Assessment is a Neglected Methodology in Suicidology.

PubMed

Davidson, Collin L; Anestis, Michael D; Gutierrez, Peter M

2017-01-02

Ecological momentary assessment (EMA) is a group of research methods that collect data frequently, in many contexts, and in real-world settings. EMA has been fairly neglected in suicidology. The current article provides an overview of EMA for suicidologists including definitions, data collection considerations, and different sampling strategies. Next, the benefits of EMA in suicidology (i.e., reduced recall bias, accurate tracking of fluctuating variables, testing assumptions of theories, use in interventions), participant safety considerations, and examples of published research that investigate self-directed violence variables using EMA are discussed. The article concludes with a summary and suggested directions for EMA research in suicidology with the particular aim to spur the increased use of this methodology among suicidologists.

From Existence to Essence: A Conceptual Model for an Appalachian Studies Curriculum.

ERIC Educational Resources Information Center

Best, Billy F.

Comprised of 4 chapters, this dissertation explores the existential premise "existence precedes essence" as applicable to development of a conceptual model for an Appalachian studies curriculum. Entitled "Personal Considerations: Pedagogy of a Hillbilly", the 1st chapter details the conflicts between the Appalachian institution…

Consideration of extinction risks for salmonids

Treesearch

Bruce Rieman; Danny Lee; Jack McIntyre; Kerry Overton; Russ Thurow

1993-01-01

Under the National Forest Management Act of 1979, the USDA Forest Service is charged with maintaining viable populations of all existing native vertebrate species on lands they administer. Accomplishment of this responsibility requires complete assessment of all federally authorized, funded, or implemented projects that may jeopardize the continued existence of a...

Antiterrorism Measures For Historic Properties

DTIC Science & Technology

2006-09-01

steel jacket on an existing concrete column (Morley Builders 1997...of the material. Figure 17. Seismic application of a steel jacket on an existing concrete column (Morley Builders 1997). Columns — Reinforced...from a previously unreinforced structure, so future irreversibility of the technique need not disqualify it from consideration by project teams. ERDC

Delphi-Discrepancy Evaluation: A Model for the Quality Control of Federal, State, and Locally Mandated Programs.

ERIC Educational Resources Information Center

Sirois, Herman A.; Iwanick, Edward F.

Legally mandated educational programs often lack specificity and guidelines for such programs are often vague and subject to considerable variability in interpretation. This situation presents perennial problems for evaluators. Few evaluation models have the flexibility for dealing with this ambiguity and variability while at the same time…

Primary School Leadership Practice: How the Subject Matters

ERIC Educational Resources Information Center

Spillane, James P.

2005-01-01

Teaching is a critical consideration in investigations of primary school leadership and not just as an outcome variable. Factoring in instruction as an explanatory variable in scholarship on school leadership involves moving away from views of teaching as a monolithic or unitary practice. When it comes to leadership in primary schools, the subject…

Fluvial processes in Puget Sound rivers and the Pacific Northwest [Chapter 3

Treesearch

John M. Buffington; Richard D. Woodsmith; Derek B. Booth; David R. Montgomery

2003-01-01

The variability of topography, geology, climate; vegetation, and land use in the Pacific Northwest creates considerable spatial and temporal variability of fluvial processes and reach-scale channel type. Here we identify process domains of typical Pacific Northwest watersheds and examine local physiographic and geologic controls on channel processes and response...

Variability in Community Characteristics and Spanish-Speaking Children's Home Language and Literacy Opportunities

ERIC Educational Resources Information Center

Reese, Leslie; Thompson, Sylvia Linan; Goldenberg, Claude

2008-01-01

Drawing on data from 14 communities in California and Texas, this paper examines the variability in language and literacy resources across communities with large numbers of Latino families. Spanish-speaking children live in communities that vary considerably with respect to language use, ethnic composition and education levels. Children's…

Spatio-Temporal Analysis of Surface Soil Moisture in Evaluating Ground Truth Monitoring Sites for Remotely Sensed Observations

USDA-ARS?s Scientific Manuscript database

Soil moisture is an intrinsic state variable that varies considerably in space and time. Although soil moisture is highly variable, repeated measurements of soil moisture at the field or small watershed scale can often reveal certain locations as being temporally stable and representative of the are...

On the Misconception of Multicollinearity in Detection of Moderating Effects: Multicollinearity Is Not Always Detrimental

ERIC Educational Resources Information Center

Shieh, Gwowen

2010-01-01

Due to its extensive applicability and computational ease, moderated multiple regression (MMR) has been widely employed to analyze interaction effects between 2 continuous predictor variables. Accordingly, considerable attention has been drawn toward the supposed multicollinearity problem between predictor variables and their cross-product term.…

The Prevalence of Low Self-Esteem in an Intellectually Disabled Forensic Population

ERIC Educational Resources Information Center

Johnson, P.

2012-01-01

Background: This was a quantitative study to measure the prevalence low self-esteem in an intellectually disabled forensic population. The dependent variables used were the adapted six-item Rosenberg Self-Esteem Scale and the adapted Evaluative Beliefs Scale. It had a repeated measures design with independent variables including consideration of…

An Approach To the Study of Patient Suicide During Psychotherapy.

ERIC Educational Resources Information Center

Selkin, James

The 1977 Denver coroner's report found that 45% of all suicide victims received psychotherapy at some time, and 21% were in treatment at the time of death. The literature on suicide places all responsibility upon the therapist. Four major sources of variance deserving consideration, however, are patient variables, therapist variables, treatment…

Childhood and/or Adolescent Sexual Experiences: Predicting Variability in Subsequent Adjustment.

ERIC Educational Resources Information Center

Seidner, Andrea L.; And Others

There is considerable debate regarding the effects of childhood sexual abuse on an individual's subsequent adjustment. To determine which variables are most useful in predicting subsequent adjustment of individuals who were involved in sexual experiences as children or adolescents, 59 female and 17 male undergraduates who reported having had a…

Considerations in the weathering of wood-plastic composites

Treesearch

Nicole M. Stark

2007-01-01

During weathering, wood-plastic composites (WPCs) can fade and lose stiffness and strength. Weathering variables that induce these changes include exposure to UV light and water. Each variable degrades WPCs independently, but can also act synergistically. Recent efforts have highlighted the need to understand how WPCs weather, and to develop schemes for protection. The...

Sexual Grooming of Children: Review of Literature and Theoretical Considerations

ERIC Educational Resources Information Center

Craven, Samantha; Brown, Sarah; Gilchrist, Elizabeth

2006-01-01

The current review aims to outline the existing understanding of sexual grooming. Issues of poor definition, the adoption of the term "grooming" and the prevalence of sexual grooming will be discussed. Consideration will be given to how prominent theories of child sexual abuse often neglect sexual grooming. This will be followed by a detailed…

Variable Selection in the Presence of Missing Data: Imputation-based Methods.

PubMed

Zhao, Yize; Long, Qi

2017-01-01

Variable selection plays an essential role in regression analysis as it identifies important variables that associated with outcomes and is known to improve predictive accuracy of resulting models. Variable selection methods have been widely investigated for fully observed data. However, in the presence of missing data, methods for variable selection need to be carefully designed to account for missing data mechanisms and statistical techniques used for handling missing data. Since imputation is arguably the most popular method for handling missing data due to its ease of use, statistical methods for variable selection that are combined with imputation are of particular interest. These methods, valid used under the assumptions of missing at random (MAR) and missing completely at random (MCAR), largely fall into three general strategies. The first strategy applies existing variable selection methods to each imputed dataset and then combine variable selection results across all imputed datasets. The second strategy applies existing variable selection methods to stacked imputed datasets. The third variable selection strategy combines resampling techniques such as bootstrap with imputation. Despite recent advances, this area remains under-developed and offers fertile ground for further research.

The `Henry Problem' of `density-driven' groundwater flow versus Tothian `groundwater flow systems' with variable density: A review of the influential Biscayne aquifer data.

NASA Astrophysics Data System (ADS)

Weyer, K. U.

2017-12-01

Coastal groundwater flow investigations at the Biscayne Bay, south of Miami, Florida, gave rise to the concept of density-driven flow of seawater into coastal aquifers creating a saltwater wedge. Within that wedge, convection-driven return flow of seawater and a dispersion zone were assumed by Cooper et al. (1964) to be the cause of the Biscayne aquifer `sea water wedge'. This conclusion was based on the chloride distribution within the aquifer and on an analytical model concept assuming convection flow within a confined aquifer without taking non-chemical field data into consideration. This concept was later labelled the `Henry Problem', which any numerical variable density flow program must be able to simulate to be considered acceptable. Both, `density-driven flow' and Tothian `groundwater flow systems' (with or without variable density conditions) are driven by gravitation. The difference between the two are the boundary conditions. 'Density-driven flow' occurs under hydrostatic boundary conditions while Tothian `groundwater flow systems' occur under hydrodynamic boundary conditions. Revisiting the Cooper et al. (1964) publication with its record of piezometric field data (heads) showed that the so-called sea water wedge has been caused by discharging deep saline groundwater driven by gravitational flow and not by denser sea water. Density driven flow of seawater into the aquifer was not found reflected in the head measurements for low and high tide conditions which had been taken contemporaneously with the chloride measurements. These head measurements had not been included in the flow interpretation. The very same head measurements indicated a clear dividing line between shallow local fresh groundwater flow and saline deep groundwater flow without the existence of a dispersion zone or a convection cell. The Biscayne situation emphasizes the need for any chemical interpretation of flow pattern to be supported by head data as energy indicators of flow fields. At the Biscayne site density-driven flow of seawater did and does not exist. Instead this site and the Florida coast line in general are the end points of local fresh and regional saline groundwater flow systems driven by gravity forces and not by density differences.

The role of anthropometry in designing for sustainability.

PubMed

Nadadur, Gopal; Parkinson, Matthew B

2013-01-01

An understanding of human factors and ergonomics facilitates the design of artefacts, tasks and environments that fulfil their users' physical and cognitive requirements. Research in these fields furthers the goal of efficiently accommodating the desired percentage of user populations through enhanced awareness and modelling of human variability. Design for sustainability (DfS) allows for these concepts to be leveraged in the broader context of designing to minimise negative impacts on the environment. This paper focuses on anthropometry and proposes three ways in which its consideration is relevant to DfS: reducing raw material consumption, increasing usage lifetimes and ethical human resource considerations. This is demonstrated through the application of anthropometry synthesis, virtual fitting, and sizing and adjustability allocation methods in the design of an industrial workstation seat for use in five distinct global populations. This work highlights the importance of and opportunities for using ergonomic design principles in DfS efforts. This research demonstrates the relevance of some anthropometry-based ergonomics concepts to the field of design for sustainability. A global design case study leverages human variability considerations in furthering three sustainable design goals: reducing raw material consumption, increasing usage lifetimes and incorporating ethical human resource considerations in design.

Regulatory Approaches for Adding Capacity to Existing Hydropower Facilities

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

Levine, Aaron L.; Curtis, Taylor L.; Kazerooni, Borna

In 2015, hydroelectric generation accounted for more than 6 percent of total net electricity generation in the United States and 46 percent of electricity generation from all renewables. The United States has considerable hydroelectric potential beyond what is already being developed. Nearly 7 GW of this potential is found by adding capacity to existing hydropower facilities. To optimize the value of hydroelectric generation, the U.S. Department of Energy's Hydropower Vision Study highlights the importance of adding capacity to existing facilities. This report provides strategic approaches and considerations for Federal Energy Regulatory Commission licensed and exempt hydropower facilities seeking to increasemore » generation capacity, which may include increases from efficiency upgrades. The regulatory approaches reviewed for this report include capacity and non-capacity amendments, adding capacity during relicensing, and adding capacity when converting a license to a 10-MW exemption.« less

A novel variable selection approach that iteratively optimizes variable space using weighted binary matrix sampling.

PubMed

Deng, Bai-chuan; Yun, Yong-huan; Liang, Yi-zeng; Yi, Lun-zhao

2014-10-07

In this study, a new optimization algorithm called the Variable Iterative Space Shrinkage Approach (VISSA) that is based on the idea of model population analysis (MPA) is proposed for variable selection. Unlike most of the existing optimization methods for variable selection, VISSA statistically evaluates the performance of variable space in each step of optimization. Weighted binary matrix sampling (WBMS) is proposed to generate sub-models that span the variable subspace. Two rules are highlighted during the optimization procedure. First, the variable space shrinks in each step. Second, the new variable space outperforms the previous one. The second rule, which is rarely satisfied in most of the existing methods, is the core of the VISSA strategy. Compared with some promising variable selection methods such as competitive adaptive reweighted sampling (CARS), Monte Carlo uninformative variable elimination (MCUVE) and iteratively retaining informative variables (IRIV), VISSA showed better prediction ability for the calibration of NIR data. In addition, VISSA is user-friendly; only a few insensitive parameters are needed, and the program terminates automatically without any additional conditions. The Matlab codes for implementing VISSA are freely available on the website: https://sourceforge.net/projects/multivariateanalysis/files/VISSA/.

Perceptions about Iranian-Kurds' ethnic-inequality in health.

PubMed

Yari, Arezoo; Nedjat, Saharnaz; Asadi-Lari, Mohsen; Majdzadeh, Reza

2017-09-12

Evidence shows ethnic-inequality is a very effective variable in the Community and individual health associated outcomes. This study focused on gaining a deeper understanding of people's perception on inequality of health in Iranian-Kurds and its determinants. The study was conducted in the three cities of Marivan, Sanandaj (capital of Kurdistan province in Iran) and Tehran (capital of the country). The study was conducted through 34 in-depth interviews and ten focus group discussions with health services users, academic graduates and health delivery service personnel. Consensus on social, mental and physical health inequality did not exist within the study participants. However, there were concerns about differences in healthcare access and utilization. Several participants believed that access to health services and socio-cultural differences of Kurds affected the healthcare utilization. Since, people perceived ethnic-inequality in healthcare access and utilization, ethnicity must be considered as a mandatory stratifier in monitoring health status and a concern during planning health interventions. People's awareness, resources management and allocation are factors requiring more consideration when choosing policy options.

Descriptive analysis and comparison of two French occupational exposure databases: COLCHIC and SCOLA.

PubMed

Mater, Gautier; Paris, Christophe; Lavoué, Jérôme

2016-05-01

Several countries have built databases of occupational hygiene measurements. In France, COLCHIC and SCOLA co-exist, started in 1987 and 2007, respectively. A descriptive comparison of the content of the two databases was carried out during the period 1987-2012, including variables, workplaces and agents, as well as exposure levels. COLCHIC and SCOLA contain, respectively, 841,682 (670 chemicals) and 152,486 records (70). They cover similar industries and occupations, and contain the same ancillary information. Across 17 common agents with >500 samples, the ratio of the median concentration in COLCHIC to the median concentration in SCOLA was 3.45 [1.03-14.3] during 2007-2012. This pattern remained when stratified by industry, task, and occupation, but was attenuated when restricted to similar sampling duration. COLCHIC and SCOLA represent a considerable source of information, but result from different purposes (prevention, regulatory). Potential differences due to strategies should evaluated when interpreting data from these databases. © 2016 Wiley Periodicals, Inc.

Sharp Contradiction for Local-Hidden-State Model in Quantum Steering

PubMed Central

Chen, Jing-Ling; Su, Hong-Yi; Xu, Zhen-Peng; Pati, Arun Kumar

2016-01-01

In quantum theory, no-go theorems are important as they rule out the existence of a particular physical model under consideration. For instance, the Greenberger-Horne-Zeilinger (GHZ) theorem serves as a no-go theorem for the nonexistence of local hidden variable models by presenting a full contradiction for the multipartite GHZ states. However, the elegant GHZ argument for Bell’s nonlocality does not go through for bipartite Einstein-Podolsky-Rosen (EPR) state. Recent study on quantum nonlocality has shown that the more precise description of EPR’s original scenario is “steering”, i.e., the nonexistence of local hidden state models. Here, we present a simple GHZ-like contradiction for any bipartite pure entangled state, thus proving a no-go theorem for the nonexistence of local hidden state models in the EPR paradox. This also indicates that the very simple steering paradox presented here is indeed the closest form to the original spirit of the EPR paradox. PMID:27562658

Sharp Contradiction for Local-Hidden-State Model in Quantum Steering

NASA Astrophysics Data System (ADS)

Chen, Jing-Ling; Su, Hong-Yi; Xu, Zhen-Peng; Pati, Arun Kumar

2016-08-01

In quantum theory, no-go theorems are important as they rule out the existence of a particular physical model under consideration. For instance, the Greenberger-Horne-Zeilinger (GHZ) theorem serves as a no-go theorem for the nonexistence of local hidden variable models by presenting a full contradiction for the multipartite GHZ states. However, the elegant GHZ argument for Bell’s nonlocality does not go through for bipartite Einstein-Podolsky-Rosen (EPR) state. Recent study on quantum nonlocality has shown that the more precise description of EPR’s original scenario is “steering”, i.e., the nonexistence of local hidden state models. Here, we present a simple GHZ-like contradiction for any bipartite pure entangled state, thus proving a no-go theorem for the nonexistence of local hidden state models in the EPR paradox. This also indicates that the very simple steering paradox presented here is indeed the closest form to the original spirit of the EPR paradox.

Retrospective estimation of the electric and magnetic field exposure conditions in in vitro experimental reports reveal considerable potential for uncertainty.

PubMed

Portelli, Lucas A; Falldorf, Karsten; Thuróczy, György; Cuppen, Jan

2018-04-01

Experiments on cell cultures exposed to extremely low frequency (ELF, 3-300 Hz) magnetic fields are often subject to multiple sources of uncertainty associated with specific electric and magnetic field exposure conditions. Here we systemically quantify these uncertainties based on exposure conditions described in a group of bioelectromagnetic experimental reports for a representative sampling of the existing literature. The resulting uncertainties, stemming from insufficient, ambiguous, or erroneous description, design, implementation, or validation of the experimental methods and systems, were often substantial enough to potentially make any successful reproduction of the original experimental conditions difficult or impossible. Without making any assumption about the true biological relevance of ELF electric and magnetic fields, these findings suggest another contributing factor which may add to the overall variability and irreproducibility traditionally associated with experimental results of in vitro exposures to low-level ELF magnetic fields. Bioelectromagnetics. 39:231-243, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Heat Transfer Study for HTS Power Transfer Cables

NASA Technical Reports Server (NTRS)

Augustynowicz, S.; Fesmire, J.

2002-01-01

Thermal losses are a key factor in the successful application of high temperature superconducting (HTS) power cables. Existing concepts and prototypes rely on the use of multilayer insulation (MLI) systems that are subject to large variations in actual performance. The small space available for the thermal insulation materials makes the application even more difficult because of bending considerations, mechanical loading, and the arrangement between the inner and outer piping. Each of these mechanical variables affects the heat leak rate. These factors of bending and spacing are examined in this study. Furthermore, a maintenance-free insulation system (high vacuum level for 20 years or longer) is a practical requirement. A thermal insulation system simulating a section of a flexible FITS power cable was constructed for test and evaluation on a research cryostat. This paper gives experimental data for the comparison of ideal MLI, MLI on rigid piping, and MLI between flexible piping. A section of insulated flexible piping was tested under cryogenic vacuum conditions including simulated bending and spacers.

Quality variations in black musli (curculigo orchioides gaertn.).

PubMed

Mathew, P P Joy Samuel; Savithri, K E; Skaria, Baby P; Kurien, Kochurani

2004-07-01

Black musli (Curculigo orchioides Gaertn.) one of the ayurvedic dasapushpa and a rejuvenating and aphrodisiac drug. Is on the verge of extinction and needs to be conserved and cultivated. Large variations are also observed in the quality of the crude drug available in the market. Study on the quality of C. orchioides in natural habitat, under cultivation and in trade in south India showed that there was considerable variation with biotypes and habitats. Drugs collected form the natural habitat was superior in quality to that produced by cultivation. Among the market samples collected from the various Zones of kerala, those from the High Ranges were superior in most of the quality parameters, which indicated its superiority for high quality drug formulation. Among the southern states, Tamil Nadu samples ranked next to High Range samples in this respect. There exists large variability in the market samples and there is felt-need for proper standardization of the crude drug for ensuring quality in the drug formulations.

The distribution of carbon monoxide and ozone in the free troposphere

NASA Technical Reports Server (NTRS)

Seiler, G.; Fishman, J.

1981-01-01

The two-dimensional distributions of CO and O3 in the free troposphere during July and August, 1974, are discussed. The data confirm the previous findings that both of these gases are considerably more abundant in the northern hemisphere, but the degree of the asymmetry is somewhat different from what had been reported previously, especially for CO. When examined with respect to other available data sets, the conclusion is drawn that a pronounced seasonal cycle exists for CO in both hemispheres which may be driven by the likely seasonal cycle of the OH radical. The data also indicate that CO concentrations exhibit significant variability with height in the northern hemisphere, whereas southern hemispheric concentrations are quite constant with altitude except in cases where interhemispheric exchange of air may be occurring. A discussion on the vertical and horizontal transport processes inferred from the CO and O3 measurements is presented. The possible interdependence of the photochemical cycles of these two trace gases is also discussed.

Considerations of Socio-Economic and Global Change Effects on Eurasian Steppes Ecosystem and Land-Atmosphere Interactions

NASA Astrophysics Data System (ADS)

Ojima, D. S.; Chuluun, T.; Temirbekov, S. S.; Mahowald, N.; Hicke, J.

2004-12-01

Dramatic changes occurred in pastoral systems of Eurasia ranging from Mongolia, China and Central Asia for the past decades. Recently, evaluation of the pastoral systems has been conducted in the region. Pastoral systems, where humans depend on livestock, exist largely in arid or semi-arid ecosystems where climate is highly variable. Interaction between ecosystems and nomadic land use systems co-shaped them in mutual adaptive ways for hundreds of years, thus making both the Mongolian rangeland ecosystem and nomadic pastoral system resilient and sustainable. Current changes in environmental conditions are affecting land-atmosphere interactions. Regional dust events, changes in hydrological cycle, and land use changes contribute to changing interactions between ecosystem and landscape processes which affect regional climate. The general trend involves greater intensification of resource exploitation at the expense of traditional patterns of extensive range utilization. This set of drivers is orthogonal to the above described climate drivers. Thus we expect climate-land use-land cover relationships to be crucially modified by the socio-economic forces.

Bronchiolitis Obliterans Syndrome: The Achilles’ Heel of Lung Transplantation

PubMed Central

Weigt, S. Samuel; DerHovanessian, Ariss; Wallace, W. Dean; Lynch, Joseph P.; Belperio, John A.

2016-01-01

Lung transplantation is a therapeutic option for patients with end-stage pulmonary disorders. Unfortunately, chronic lung allograft dysfunction (CLAD), most commonly manifest as bronchiolitis obliterans syndrome (BOS), continues to be highly prevalent and is the major limitation to long-term survival. The pathogenesis of BOS is complex and involves alloimmune and nonalloimmune pathways. Clinically, BOS manifests as airway obstruction and dyspnea that are classically progressive and ultimately fatal; however, the course is highly variable, and distinguishable phenotypes may exist. There are few controlled studies assessing treatment efficacy, but only a minority of patients respond to current treatment modalities. Ultimately, preventive strategies may prove more effective at prolonging survival after lung transplantation, but their remains considerable debate and little data regarding the best strategies to prevent BOS. A better understanding of the risk factors and their relationship to the pathological mechanisms of chronic lung allograft rejection should lead to better pharmacological targets to prevent or treat this syndrome. PMID:23821508

Transdermal patches: history, development and pharmacology

PubMed Central

Pastore, Michael N; Kalia, Yogeshvar N; Horstmann, Michael; Roberts, Michael S

2015-01-01

Transdermal patches are now widely used as cosmetic, topical and transdermal delivery systems. These patches represent a key outcome from the growth in skin science, technology and expertise developed through trial and error, clinical observation and evidence-based studies that date back to the first existing human records. This review begins with the earliest topical therapies and traces topical delivery to the present-day transdermal patches, describing along the way the initial trials, devices and drug delivery systems that underpin current transdermal patches and their actives. This is followed by consideration of the evolution in the various patch designs and their limitations as well as requirements for actives to be used for transdermal delivery. The properties of and issues associated with the use of currently marketed products, such as variability, safety and regulatory aspects, are then described. The review concludes by examining future prospects for transdermal patches and drug delivery systems, such as the combination of active delivery systems with patches, minimally invasive microneedle patches and cutaneous solutions, including metered-dose systems. PMID:25560046

Precision medicine and drug development in Alzheimer's disease: The importance of sexual dimorphism and patient stratification.

PubMed

Hampel, Harald; Vergallo, Andrea; Giorgi, Filippo Sean; Kim, Seung Hyun; Depypere, Herman; Graziani, Manuela; Saidi, Amira; Nisticò, Robert; Lista, Simone

2018-06-12

Neurodegenerative diseases (ND) are among the leading causes of disability and mortality. Considerable sex differences exist in the occurrence of the various manifestations leading to cognitive decline. Alzheimer's disease (AD) exhibits substantial sexual dimorphisms and disproportionately affects women. Women have a higher life expectancy compared to men and, consequently, have more lifespan to develop AD. The emerging precision medicine and pharmacology concepts - taking into account the individual genetic and biological variability relevant for disease risk, prevention, detection, diagnosis, and treatment - are expected to substantially enhance our knowledge and management of AD. Stratifying the affected individuals by sex and gender is an important basic step towards personalization of scientific research, drug development, and care. We hypothesize that sex and gender differences, extending from genetic to psychosocial domains, are highly relevant for the understanding of AD pathophysiology, and for the conceptualization of basic/translational research and for clinical therapy trial design. Copyright © 2018 Elsevier Inc. All rights reserved.

Subglacial discharges create fluctuating foraging hotspots for sea birds in tidewater glacier bays.

PubMed

Urbanski, Jacek Andrzej; Stempniewicz, Lech; Węsławski, Jan Marcin; Dragańska-Deja, Katarzyna; Wochna, Agnieszka; Goc, Michał; Iliszko, Lech

2017-03-07

Although the processes occurring at the front of an ice face in tidewater glacier bays still await thorough investigation, their importance to the rapidly changing polar environment is spurring a considerable research effort. Glacier melting, sediment delivery and the formation of seabird foraging hotspots are governed by subglacial discharges of meltwater. We have combined the results of tracking black-legged kittiwakes Rissa tridactyla equipped with GPS loggers, analyses of satellite images and in situ measurements of water temperature, salinity and turbidity in order to examine the magnitude and variability of such hotspots in the context of glacier bay hydrology. Small though these hotspots are in size, foraging in them appears to be highly intensive. They come into existence only if the subglacial discharge reaches the surface, if the entrainment velocity at a conduit is high and if there is sufficient macroplankton in the entrainment layer. The position and type of subglacial discharges may fluctuate in time and space, thereby influencing glacier bay hydrology and the occurrence of foraging hotspots.

The importance of radiation for semiempirical water-use efficiency models

NASA Astrophysics Data System (ADS)

Boese, Sven; Jung, Martin; Carvalhais, Nuno; Reichstein, Markus

2017-06-01

Water-use efficiency (WUE) is a fundamental property for the coupling of carbon and water cycles in plants and ecosystems. Existing model formulations predicting this variable differ in the type of response of WUE to the atmospheric vapor pressure deficit of water (VPD). We tested a representative WUE model on the ecosystem scale at 110 eddy covariance sites of the FLUXNET initiative by predicting evapotranspiration (ET) based on gross primary productivity (GPP) and VPD. We found that introducing an intercept term in the formulation increases model performance considerably, indicating that an additional factor needs to be considered. We demonstrate that this intercept term varies seasonally and we subsequently associate it with radiation. Replacing the constant intercept term with a linear function of global radiation was found to further improve model predictions of ET. Our new semiempirical ecosystem WUE formulation indicates that, averaged over all sites, this radiation term accounts for up to half (39-47 %) of transpiration. These empirical findings challenge the current understanding of water-use efficiency on the ecosystem scale.

NEW EVIDENCE SUPPORTING MEMBERSHIP FOR TW NOR IN LYNGA 6 AND THE CENTAURUS SPIRAL ARM

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

Majaess, Daniel; Turner, David; Moni Bidin, Christian

2011-11-10

The putative association between the 10{sub .}{sup d}8 classical Cepheid TW Nor and the open cluster Lynga 6 has generated considerable debate in the literature. New JHK{sub s} photometry in tandem with existing radial velocities for Lynga 6 stars implies cluster membership for TW Nor and establishes the variable as a high-weight calibrator for classical Cepheid relations. Fundamental mean parameters determined for Lynga 6 are: d = 1.91 {+-} 0.10 kpc, E(J - H) = 0.38 {+-} 0.02, and log {tau} = 7.9 {+-} 0.1. The Benedict et al./Turner Galactic VI{sub c} Wesenheit function was revised using TW Nor's newmore » parameters: W{sub VI,0} (- 3.37 {+-} 0.08)log P{sub 0} - 2.48 {+-} 0.08. TW Nor/Lynga 6 lie beyond the Sagittarius-Carina spiral arm and occupy the Centaurus arm, along with innumerable young Cepheids and clusters (e.g., VW Cen and VVV CL070).« less

Functional recovery of anterior semicircular canal afferents following hair cell regeneration in birds

NASA Technical Reports Server (NTRS)

Boyle, Richard; Highstein, Stephen M.; Carey, John P.; Xu, Jinping

2002-01-01

Streptomycin sulfate (1.2 g/kg i.m.) was administered for 5 consecutive days to 5-7-day-old white Leghorn chicks; this causes damage to semicircular canal hair cells that ultimately regenerate to reform the sensory epithelium. During the recovery period, electrophysiological recordings were taken sequentially from anterior semicircular canal primary afferents using an indentation stimulus of the canal that has been shown to mimic rotational stimulation. Chicks were assigned to an early (14-18 days; n = 8), intermediate (28-34 days; n = 5), and late (38-58 days; n = 4) period based on days after treatment. Seven untreated chicks, 15-67 days old, provided control data. An absence of background and indent-induced discharge was the prominent feature of afferents in the early period: only "silent" afferents were encountered in 5/8 experiments. In several of these chicks, fascicles of afferent fibers were seen extending up to the epithelium that was void of hair cells, and intra- and extracellular biocytin labeling revealed afferent processes penetrating into the supporting cell layer of the crista. In 3/8 chicks 74 afferents could be characterized, and they significantly differed from controls (n = 130) by having a lower discharge rate and a negligible response to canal stimulation. In the intermediate period there was considerable variability in discharge properties of 121 afferents, but as a whole the number of "silent" fibers in the canal nerve diminished, the background rate increased, and a response to canal stimulation detected. Individually biocytin-labeled afferents had normal-appearing terminal specializations in the sensory epithelium by 28 days poststreptomycin. In the late period, afferents (n = 58) remained significantly different from controls in background discharge properties and response gain. The evidence suggests that a considerable amount of variability exists between chicks in the return of vestibular afferent function following ototoxic injury and that the secretory function of regenerating hair cells might become functional before their transducer function.

Three Years of TRMM Precipitation Features. Part 1; Radar, Radiometric, and Lightning Characteristics

NASA Technical Reports Server (NTRS)

Cecil, Daniel J.; Goodman, Steven J.; Boccippio, Dennis J.; Zipser, Edward J.; Nesbitt, Stephen W.

2004-01-01

During its first three years, the Tropical Rainfall Measuring Mission (TRMM) satellite observed nearly six million precipitation features. The population of precipitation features is sorted by lightning flash rate, minimum brightness temperature, maximum radar reflectivity, areal extent, and volumetric rainfall. For each of these characteristics, essentially describing the convective intensity or the size of the features, the population is broken into categories consisting of the top 0.001%, top 0.01%, top 0.1%, top 1%, top 2.4%, and remaining 97.6%. The set of 'weakest / smallest' features comprises 97.6% of the population because that fraction does not have detected lightning, with a minimum detectable flash rate 0.7 fl/min. The greatest observed flash rate is 1351 fl/min; the lowest brightness temperatures are 42 K (85-GHz) and 69 K (37- GHz). The largest precipitation feature covers 335,000 sq km and the greatest rainfall from an individual precipitation feature exceeds 2 x 10(exp 12) kg of water. There is considerable overlap between the greatest storms according to different measures of convective intensity. The largest storms are mostly independent of the most intense storms. The set of storms producing the most rainfall is a convolution of the largest and the most intense storms. This analysis is a composite of the global tropics and subtropics. Significant variability is known to exist between locations, seasons, and meteorological regimes. Such variability will be examined in Part II. In Part I, only a crude land / Ocean separation is made. The known differences in bulk lightning flash rates over land and Ocean result from at least two differences in the precipitation feature population: the frequency of occurrence of intense storms, and the magnitude of those intense storms that do occur. Even when restricted to storms with the same brightness temperature, same size, or same radar reflectivity aloft, the storms over water are considerably less likely to produce lightning than are comparable storms over land.

Three Years of TRMM Precipitation Features. Part 1; Radar, Radiometric, and Lightning Characteristics

NASA Technical Reports Server (NTRS)

Cecil, Daniel J.; Goodman, Steven J.; Boccippio, Dennis J.; Zipser, Edward J.; Nesbitt, Stephen W.

2005-01-01

During its first three years, the Tropical Rainfall Measuring Mission (TRMM) satellite observed nearly six million precipitation features. The population of precipitation features is sorted by lightning flash rate, minimum brightness temperature, maximum radar reflectivity. areal extent, and volumetric rainfall. For each of these characteristics, essentially describing the convective intensity or the size of the features, the population is broken into categories consisting of the top 0.001%, top 0.01%, top 0.1%, top 1%, top 2.4%. and remaining 97.6%. The set of weakest/smallest features composes 97.6% of the population because that fraction does not have detected lightning, with a minimum detectable flash rate of 0.7 flashes (fl) per minute. The greatest observed flash rate is 1351 fl per minute; the lowest brightness temperatures are 42 K (85 GHz) and 69 K (37 GHz). The largest precipitation feature covers 335 000 square kilometers and the greatest rainfall from an individual precipitation feature exceeds 2 x 10 kg per hour of water. There is considerable overlap between the greatest storms according to different measures of convective intensity. The largest storms are mostly independent of the most intense storms. The set of storms producing the most rainfall is a convolution of the largest and the most intense storms. This analysis is a composite of the global Tropics and subtropics. Significant variability is known to exist between locations. seasons, and meteorological regimes. Such variability will be examined in Part II. In Part I, only a crude land-ocean separation is made. The known differences in bulk lightning flash rates over land and ocean result from at least two differences in the precipitation feature population: the frequency of occurrence of intense storms and the magnitude of those intense storms that do occur. Even when restricted to storms with the same brightness temperature, same size, or same radar reflectivity aloft, the storms over water are considerably less likely to produce lightning than are comparable storms over land.

On the dynamic forcing of short-term climate fluctuations by feedback mechanisms

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

Reiter, E.R.

1979-09-01

The energies involved in the general circulation of the atmosphere, especially the zonal available potential energy, show considerable interannual variability, suggesting the presence of various internal feedback mechanisms in the ocean-atmosphere system. Sea-surface temperature (SST) variations appear to have some effect on the hydrological cycle. The possible existence of feedback mechanisms between ocean and atmosphere seem to be evident in some of the data from the North Pacific and North Atlantic. One of these proposed mechanisms involves the variation in the convergence between the North and South Pacific trade-wind systems and is strongly reflected in rainfall variability within the drymore » region of the equatorial Pacific. Similar variations appear in low-latitude SST anomalies. The convergence between the two trade-wind systems in the Atlantic region also undergoes marked interannual variations. This quasi-biennial oscillation (QBO) in trade-wind convergence over the Atlantic appears to be tied to the global QBO of equatorial stratospheric winds and to regional rainfall regimes in the dry region of northeastern Brazil. A variability pattern of SST's with a QBO has been detected off the coast of Senegal, in the Gulf of Guinea and even in the Gulf Stream as it leaves the North American continental shelf. Possible physical connections between some of these QBO's are pointed out by a hypothetical feedback model. It is also suggested that interaction of a QBO with the annual cycle may lead to beating frequencies resembling climatic trends of a duration of several years.« less

The paradox of cooling streams in a warming world: Regional climate trends do not parallel variable local trends in stream temperature in the Pacific continental United States

USGS Publications Warehouse

Arismendi, Ivan; Johnson, Sherri; Dunham, Jason B.; Haggerty, Roy; Hockman-Wert, David

2012-01-01

Temperature is a fundamentally important driver of ecosystem processes in streams. Recent warming of terrestrial climates around the globe has motivated concern about consequent increases in stream temperature. More specifically, observed trends of increasing air temperature and declining stream flow are widely believed to result in corresponding increases in stream temperature. Here, we examined the evidence for this using long-term stream temperature data from minimally and highly human-impacted sites located across the Pacific continental United States. Based on hypothesized climate impacts, we predicted that we should find warming trends in the maximum, mean and minimum temperatures, as well as increasing variability over time. These predictions were not fully realized. Warming trends were most prevalent in a small subset of locations with longer time series beginning in the 1950s. More recent series of observations (1987-2009) exhibited fewer warming trends and more cooling trends in both minimally and highly human-influenced systems. Trends in variability were much less evident, regardless of the length of time series. Based on these findings, we conclude that our perspective of climate impacts on stream temperatures is clouded considerably by a lack of long-termdata on minimally impacted streams, and biased spatio-temporal representation of existing time series. Overall our results highlight the need to develop more mechanistic, process-based understanding of linkages between climate change, other human impacts and stream temperature, and to deploy sensor networks that will provide better information on trends in stream temperatures in the future.

Consideration of immediate and future consequences, smoking status, and body mass index.

PubMed

Adams, Jean

2012-03-01

Health-related behaviors often involve immediate costs to achieve long-term benefits. How one considers the future outcomes of present day behaviors (e.g., temporal orientation) may play a role in engagement in healthy behaviors. The Consideration of Future Consequences Scale (CFCS) measures temporal orientation on a unidimensional continuum. Recently, 2 subscales of the CFCS have been reported: immediate (CFC-I) and future (CFC-F) consequences. These support a multidimensional conceptualization of temporal orientation. Confirmatory factor analysis was performed on CFCS data. The associations between 2 health-related variables [smoking and body mass index (BMI)] and each subscale were then explored, controlling for sociodemographic variables. A random sample of 2,000 individuals aged 18 years or over was selected from the edited electoral role for one English city and sent a postal questionnaire, including the CFCS and questions on age, gender, socioeconomic position, and self-reported current smoking status and BMI. Complete data was provided by 800 participants (response rate = 40.0%). The 2-factor model fitted CFCS data better than the 1-factor model. In multiple linear regression, CFC-I was positively associated with BMI, B (95% confidence interval [CI]) = 0.47 (0.06 to 0.88), p = .025; and odds of being a current smoker, odds ratio (95% CI) = 1.28 (1.02 to 1.60), p = .035; CFC-F was not associated with health-related variables. These data support the multidimensional conceptualization of temporal orientation. Consideration of immediate consequences may be a more important determinant of health-related behaviors than consideration of future consequences.

Using water to cool cattle: behavioral and physiological changes associated with voluntary use of cow showers.

PubMed

Legrand, A; Schütz, K E; Tucker, C B

2011-07-01

Water is commonly used to cool cattle in summer either at milking or over the feed bunk, but little research has examined how dairy cows voluntarily use water separate from these locations. The objectives were to describe how and when dairy cattle voluntarily used an overhead water source separate from other resources, such as feed, and how use of this water affected behavioral and physiological indicators of heat stress. Half of the 24 nonlactating cattle tested had access to a "cow shower" composed of 2 shower heads activated by a pressure-sensitive floor. All animals were individually housed to prevent competition for access to the shower. Over 5 d in summer (air temperature=25.3±3.3°C, mean ± standard deviation), cattle spent 3.0±2.1 h/24h in the shower, but considerable variability existed between animals (individual daily values ranged from 0.0 to 8.2 h/24h). A portion of this variation can be explained by weather; shower use increased by 0.3h for every 1°C increase in ambient temperature. Cows preferentially used the shower during the daytime, with 89±12% of the time spent in the shower between 1000 and 1900 h. Respiration rate and skin temperature did not differ between treatments [53 vs. 61 breaths/min and 35.0 vs. 35.4°C in shower and control cows, respectively; standard error of the difference (SED)=5.6 breaths/min and 0.49°C]. In contrast, body temperature of cows provided with a shower was 0.2°C lower than control cows in the evening (i.e., 1800 to 2100h; SED=0.11°C). Cows with access to a shower spent half as much time near the water trough than control animals, and this pattern became more pronounced as the temperature-humidity index increased. In addition, cattle showed other behavioral changes to increasing heat load; they spent less time lying when heat load index increased, but the time spent lying, feeding, and standing without feeding did not differ between treatments. Cows had higher respiration rate, skin temperature, and body temperature as heat load index increased, regardless of treatment. These data suggest that cattle, when given the opportunity, will make considerable use of a shower to reduce heat load, but that individuals are highly variable in their use of this resource. The variability between cows indicates that the behavioral response to water is likely an important, but poorly understood, consideration in the design of sprinkler systems used for summer cooling. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Examining variations in health within rural Canada.

PubMed

Lavergne, M Ruth; Kephart, George

2012-01-01

Differences in health between urban and rural areas of Canada are well documented. Canadian rural communities are remarkably heterogeneous in terms of social, economic, and geographic characteristics. There is reason to believe that there is also considerable heterogeneity in health within rural Canada but existing literature has not given this adequate consideration. This article describes heterogeneity in health along the urban-rural continuum, both between and within categories of rural areas. Factors that may explain observed variations are then examined. The study population included all adult (>18 years) respondents on the Canadian Community Health Survey Cycle 1.1, linked to census subdivision-level data from the corresponding Canadian Census. Study areas were classified according to Metropolitan Influenced Zones (MIZ), which group rural areas based on their degree of connectivity with nearby urban areas. Dichotomized Health Utilities Index (HUI) scores were the outcome variable. Random-intercept logistic regression models investigated the associations of HUI with individual and area characteristics. To describe between-area variation in health, the proportion of the total variation accounted for by the area random effect (the intra-class correlation coefficient [ICC]) was estimated. To aid interpretation of the magnitude of the effect of area relative to other variables in the models, the ICC was also expressed as a median odds ratio (MOR), or the median amount by which the probability of disability will change for an individual who moves from one area to another. On a descriptive level, poorer health was observed in more remote rural areas, but the size of estimated effects for categories of rural areas was generally small compared with effects of other individual and area variables, and with the degree of heterogeneity between areas. The composition of rural areas is important in order to understand patterns in health. Individual income, education, and employment, and area characteristics such as Francophone or Aboriginal populations, and migration patterns help explain the gradient in health by MIZ, but considerable heterogeneity in health within categories of MIZ remains. In models stratified by MIZ, significant between-area heterogeneity was observed in all models, with MORs ranging from 1.18 to 1.53. It was observed that heterogeneity in health among rural areas is substantial, and generally larger than the effect of rurality, itself, on health. More attention is needed to understand the characteristics of Canada's heterogeneous rural communities, and the different processes by which disparities in health emerge and persist. The findings suggest that a focus on rurality alone, emphasizing urban versus rural disparities, or even continuum-based approaches like MIZ, may be less informative than finding ways to classify and examine different types of rural areas according to factors relevant to health.

Recovery considerations for possible high inclination long duration earth orbital missions

NASA Technical Reports Server (NTRS)

Obriant, T. E.; Ferguson, J. E.

1969-01-01

Problem areas are discussed and various solutions proposed. One of the major recovery problems encountered with missions having higher orbital inclinations than previous missions is the greater likelihood of severe weather conditions in the landing zones, especially if landing zones are optimized for orbital coverage considerations. Restricting the reentry window and increasing in-orbit wait times can partially eliminate the weather problem, but the possibility of emergency landings at higher latitudes still exists. It can be expected that the increased confidence level in spacecraft reliability that will exist by the time the high-inclination missions are flown will reduce the probabilities of an emergency landing in an unfavorable recovery location to a very low level.

The development of a gender identity psychosocial clinic: treatment issues, logistical considerations, interdisciplinary cooperation, and future initiatives.

PubMed

Leibowitz, Scott F; Spack, Norman P

2011-10-01

Few interdisciplinary treatment programs that tend to the needs of youth with gender nonconforming behaviors, expressions, and identities exist in academic medical centers with formal residency training programs. Despite this, the literature provides evidence that these youth have higher rates of poor psychosocial adjustment and suicide attempts. This article explores the logistical considerations involved in developing a specialized interdisciplinary service to these gender minority youth in accordance with the existing treatment guidelines.Demographic data will be presented and treatment issues will be explored. The impact that a specialized interdisciplinary treatment program has on clinical expansion, research development, education and training, and community outreach initiatives is discussed.

Comparing meta-analysis and ecological-longitudinal analysis in time-series studies. A case study of the effects of air pollution on mortality in three Spanish cities

PubMed Central

Saez, M; Figueiras, A; Ballester, F; Perez-Hoyos, S; Ocana, R; Tobias, A

2001-01-01

STUDY OBJECTIVE—The objective of this paper is to introduce a different approach, called the ecological-longitudinal, to carrying out pooled analysis in time series ecological studies. Because it gives a larger number of data points and, hence, increases the statistical power of the analysis, this approach, unlike conventional ones, allows the complementation of aspects such as accommodation of random effect models, of lags, of interaction between pollutants and between pollutants and meteorological variables, that are hardly implemented in conventional approaches.
DESIGN—The approach is illustrated by providing quantitative estimates of the short-term effects of air pollution on mortality in three Spanish cities, Barcelona, Valencia and Vigo, for the period 1992-1994. Because the dependent variable was a count, a Poisson generalised linear model was first specified. Several modelling issues are worth mentioning. Firstly, because the relations between mortality and explanatory variables were non-linear, cubic splines were used for covariate control, leading to a generalised additive model, GAM. Secondly, the effects of the predictors on the response were allowed to occur with some lag. Thirdly, the residual autocorrelation, because of imperfect control, was controlled for by means of an autoregressive Poisson GAM. Finally, the longitudinal design demanded the consideration of the existence of individual heterogeneity, requiring the consideration of mixed models.
MAIN RESULTS—The estimates of the relative risks obtained from the individual analyses varied across cities, particularly those associated with sulphur dioxide. The highest relative risks corresponded to black smoke in Valencia. These estimates were higher than those obtained from the ecological-longitudinal analysis. Relative risks estimated from this latter analysis were practically identical across cities, 1.00638 (95% confidence intervals 1.0002, 1.0011) for a black smoke increase of 10 µg/m3 and 1.00415 (95% CI 1.0001, 1.0007) for a increase of 10 µg/m3 of sulphur dioxide. Because the statistical power is higher than in the individual analysis more interactions were statistically significant, especially those among air pollutants and meteorological variables.
CONCLUSIONS—Air pollutant levels were related to mortality in the three cities of the study, Barcelona, Valencia and Vigo. These results were consistent with similar studies in other cities, with other multicentric studies and coherent with both, previous individual, for each city, and multicentric studies for all three cities.


Keywords: air pollution; mortality; longitudinal studies PMID:11351001

Recommendations for the inclusion of Fabry disease as a rare febrile condition in existing algorithms for fever of unknown origin.

PubMed

Manna, Raffaele; Cauda, Roberto; Feriozzi, Sandro; Gambaro, Giovanni; Gasbarrini, Antonio; Lacombe, Didier; Livneh, Avi; Martini, Alberto; Ozdogan, Huri; Pisani, Antonio; Riccio, Eleonora; Verrecchia, Elena; Dagna, Lorenzo

2017-10-01

Fever of unknown origin (FUO) is a rather rare clinical syndrome representing a major diagnostic challenge. The occurrence of more than three febrile attacks with fever-free intervals of variable duration during 6 months of observation has recently been proposed as a subcategory of FUO, Recurrent FUO (RFUO). A substantial number of patients with RFUO have auto-inflammatory genetic fevers, but many patients remain undiagnosed. We hypothesize that this undiagnosed subgroup may be comprised of, at least in part, a number of rare genetic febrile diseases such as Fabry disease. We aimed to identify key features or potential diagnostic clues for Fabry disease as a model of rare genetic febrile diseases causing RFUO, and to develop diagnostic guidelines for RFUO, using Fabry disease as an example of inserting other rare diseases in the existing FUO algorithms. An international panel of specialists in recurrent fevers and rare diseases, including internists, infectious disease specialists, rheumatologists, gastroenterologists, nephrologists, and medical geneticists convened to review the existing diagnostic algorithms, and to suggest recommendations for arriving at accurate diagnoses on the basis of available literature and clinical experience. By combining specific features of rare diseases with other diagnostic considerations, guidelines have been designed to raise awareness and identify rare diseases among other causes of FUO. The proposed guidelines may be useful for the inclusion of rare diseases in the diagnostic algorithms for FUO. A wide spectrum of patients will be needed to validate the algorithm in different clinical settings.

Geologic effects on groundwater salinity and discharge into an estuary

USGS Publications Warehouse

Russonielloa, Christopher J.; Fernandeza, Cristina; Bratton, John F.; Banaszakc, Joel F.; Krantzc, David E.; Andresd, Scott; Konikow, Leonard F.; Michaela, Holly A.

2013-01-01

Submarine groundwater discharge (SGD) can be an important pathway for transport of nutrients and contaminants to estuaries. A better understanding of the geologic and hydrologic controls on these fluxes is critical for their estimation and management. We examined geologic features, porewater salinity, and SGD rates and patterns at an estuarine study site. Seismic data showed the existence of paleovalleys infilled with estuarine mud and peat that extend hundreds of meters offshore. A low-salinity groundwater plume beneath this low-permeability fill was mapped with continuous resistivity profiling. Extensive direct SGD measurements with seepage meters (n = 551) showed fresh groundwater discharge patterns that correlated well with shallow porewater salinity and the hydrogeophysical framework. Small-scale variability in fresh and saline discharge indicates influence of meter-scale geologic heterogeneity, while site-scale discharge patterns are evidence of the influence of the paleovalley feature. Beneath the paleovalley fill, fresh groundwater flows offshore and mixes with saltwater before discharging along paleovalley flanks. On the adjacent drowned interfluve where low-permeability fill is absent, fresh groundwater discharge is focused at the shoreline. Shallow saltwater exchange was greatest across sandy sediments and where fresh SGD was low. The geologic control of groundwater flowpaths and discharge salinity demonstrated in this work are likely to affect geochemical reactions and the chemical loads delivered by SGD to coastal surface waters. Because similar processes are likely to exist in other estuaries where drowned paleovalleys commonly cross modern shorelines, the existence and implications of complex hydrogeology are important considerations for studies of groundwater fluxes and related management decisions.

Socio-demographic, health, and tinnitus related variables affecting tinnitus severity.

PubMed

Hoekstra, Carlijn E L; Wesdorp, Francina M; van Zanten, Gijsbert A

2014-01-01

Tinnitus is a highly prevalent symptom with potential severe morbidity. Fortunately, only a small proportion of the population experience problems due to their tinnitus in such a degree that it adversely affects their quality of life (clinically significant tinnitus). It is not known why these individuals develop more burden from tinnitus. It seems likely that the severity of tinnitus can be influenced by different factors, such as socio-demographic or tinnitus characteristics or additional health complaints. It remains unclear from the current literature as to what are the main independent variables that have a bearing on tinnitus severity. This study addresses this problem by investigating variables previously described in the literature as well as additional variables. The aim of this study is to identify socio-demographic, health, and tinnitus variables that independently relate to tinnitus severity the most. This is a retrospective cohort study performed at the Tinnitus Care Group of the University Medical Center, Utrecht, in 309 consecutively seen chronic tinnitus patients. At this care group, patients are examined according to a structured diagnostic protocol, including history-taking by an otorhinolaryngologist and audiologist, physical examination, and audiometry. Based on results from previous research and theoretical considerations, a subset of data acquired through this diagnostic protocol were selected and used in this study. Univariate and multivariate correlations with tinnitus severity were investigated for 28 socio-demographic, health, and tinnitus variables. Tinnitus severity was measured with the Tinnitus Questionnaire (TQ) and the Tinnitus Handicap Inventory (THI). Eighteen variables related univariately with the TQ and 16 variables related univariately with the THI. Among these, 14 variables related univariately with both the TQ and the THI. Multivariate analyses showed three variables with an independent significant effect on both the TQ and the THI: percentage of tinnitus awareness during the day, self-reported depression and/or anxiety, and loudness on a Visual Analogue Scale. Three additional variables contributed independently significantly to the explained variance in either the TQ or the THI: level of education, somatic complaints, and tinnitus variability in loudness and/or pitch on a Visual Analogue Scale. These variables were among the first not to reach significance on the other questionnaire. Tinnitus severity is shown to be strongly related to percentage of tinnitus awareness during the day, self-reported depression and/or anxiety, subjectively experienced loudness, level of education, existence of additional somatic complaints, and subjectively experienced variability in loudness and/or pitch. Further research is needed to investigate the causal relationship between these variables and tinnitus severity. This knowledge may contribute to a better recognition, follow-up, and/or counseling of more vulnerable patients.

Carbon balance of the terrestrial biosphere in the twentieth century: analyses of CO2, climate and land use effects with four process-based ecosystem models

USGS Publications Warehouse

McGuire, A.D.; Sitch, S.; Clein, Joy S.; Dargaville, R.; Esser, G.; Foley, J.; Heimann, Martin; Joos, F.; Kaplan, J.; Kicklighter, D.W.; Meier, R.A.; Melillo, J.M.; Moore, B.; Prentice, I.C.; Ramankutty, N.; Reichenau, T.; Schloss, A.; Tian, H.; Williams, L.J.; Wittenberg, U.

2001-01-01

The concurrent effects of increasing atmospheric CO2 concentration, climate variability, and cropland establishment and abandonment on terrestrial carbon storage between 1920 and 1992 were assessed using a standard simulation protocol with four process-based terrestrial biosphere models. Over the long-term(1920–1992), the simulations yielded a time history of terrestrial uptake that is consistent (within the uncertainty) with a long-term analysis based on ice core and atmospheric CO2 data. Up to 1958, three of four analyses indicated a net release of carbon from terrestrial ecosystems to the atmosphere caused by cropland establishment. After 1958, all analyses indicate a net uptake of carbon by terrestrial ecosystems, primarily because of the physiological effects of rapidly rising atmospheric CO2. During the 1980s the simulations indicate that terrestrial ecosystems stored between 0.3 and 1.5 Pg C yr−1, which is within the uncertainty of analysis based on CO2 and O2 budgets. Three of the four models indicated (in accordance with O2 evidence) that the tropics were approximately neutral while a net sink existed in ecosystems north of the tropics. Although all of the models agree that the long-term effect of climate on carbon storage has been small relative to the effects of increasing atmospheric CO2 and land use, the models disagree as to whether climate variability and change in the twentieth century has promoted carbon storage or release. Simulated interannual variability from 1958 generally reproduced the El Niño/Southern Oscillation (ENSO)-scale variability in the atmospheric CO2 increase, but there were substantial differences in the magnitude of interannual variability simulated by the models. The analysis of the ability of the models to simulate the changing amplitude of the seasonal cycle of atmospheric CO2 suggested that the observed trend may be a consequence of CO2 effects, climate variability, land use changes, or a combination of these effects. The next steps for improving the process-based simulation of historical terrestrial carbon include (1) the transfer of insight gained from stand-level process studies to improve the sensitivity of simulated carbon storage responses to changes in CO2 and climate, (2) improvements in the data sets used to drive the models so that they incorporate the timing, extent, and types of major disturbances, (3) the enhancement of the models so that they consider major crop types and management schemes, (4) development of data sets that identify the spatial extent of major crop types and management schemes through time, and (5) the consideration of the effects of anthropogenic nitrogen deposition. The evaluation of the performance of the models in the context of a more complete consideration of the factors influencing historical terrestrial carbon dynamics is important for reducing uncertainties in representing the role of terrestrial ecosystems in future projections of the Earth system.

Selecting Models for Measuring Change When True Experimental Conditions Do Not Exist.

ERIC Educational Resources Information Center

Fortune, Jim C.; Hutson, Barbara A.

1984-01-01

Measuring change when true experimental conditions do not exist is a difficult process. This article reviews the artifacts of change measurement in evaluations and quasi-experimental designs, delineates considerations in choosing a model to measure change under nonideal conditions, and suggests ways to organize models to facilitate selection.…

Cesium Neonide: Molecule or Thermochemical Exercise?

ERIC Educational Resources Information Center

Blake, P. G.; Clack, D. W.

1982-01-01

Thermochemical cycles are used to decide which hypothetical compounds might exist and, if not, what is the factor that condemns them to non-existence. Hypothetical compounds of rare gases provide examples of the approach with added historical interest that thermochemical considerations led to prediction and demonstration that XePtF-6 was stable.…

Physics in one dimension: theoretical concepts for quantum many-body systems.

PubMed

Schönhammer, K

2013-01-09

Various sophisticated approximation methods exist for the description of quantum many-body systems. It was realized early on that the theoretical description can simplify considerably in one-dimensional systems and various exact solutions exist. The focus in this introductory paper is on fermionic systems and the emergence of the Luttinger liquid concept.

Alcohol advertising and adolescents.

PubMed

Strasburger, Victor C

2002-04-01

Considerable research now exists that the media may exert a powerful influence on adolescents' drug-taking behavior. Teens view an average of 2,000 beer and wine ads per year in the US. In addition, television shows, movies, and music videos contain considerable amounts of alcohol use. This article will discuss the available research and offers suggestions to make the media healthier for teenagers.

Quantifying Landscape Spatial Pattern: What Is the State of the Art?

Treesearch

Eric J. Gustafson

1998-01-01

Landscape ecology is based on the premise that there are strong links between ecological pattern and ecological function and process. Ecological systems are spatially heterogeneous, exhibiting consid-erable complexity and variability in time and space. This variability is typically represented by categorical maps or by a collection of samples taken at specific spatial...

The Rasch Rating Model and the Disordered Threshold Controversy

ERIC Educational Resources Information Center

Adams, Raymond J.; Wu, Margaret L.; Wilson, Mark

2012-01-01

The Rasch rating (or partial credit) model is a widely applied item response model that is used to model ordinal observed variables that are assumed to collectively reflect a common latent variable. In the application of the model there is considerable controversy surrounding the assessment of fit. This controversy is most notable when the set of…

Expanding Reliability Generalization Methods with KR-21 Estimates: An RG Study of the Coopersmith Self-Esteem Inventory.

ERIC Educational Resources Information Center

Lane, Ginny G.; White, Amy E.; Henson, Robin K.

2002-01-01

Conducted a reliability generalizability study on the Coopersmith Self-Esteem Inventory (CSEI; S. Coopersmith, 1967) to examine the variability of reliability estimates across studies and to identify study characteristics that may predict this variability. Results show that reliability for CSEI scores can vary considerably, especially at the…

Doing Televised Rhetorical Analysis as a Means of Promoting College Awareness in a Target Market.

ERIC Educational Resources Information Center

Schnell, Jim

This paper describes aspects of doing televised rhetorical analysis as they relate to the promotion of college awareness in a particular target market. Considerations in the paper include variables that most professors encounter in their efforts to address the "service" expectations of their employment and how these variables can be…

Exploration of the Core and Variable Dimensions of Extensive Reading Research and Pedagogy

ERIC Educational Resources Information Center

Waring, Rob; McLean, Stuart

2015-01-01

The Extensive Reading Foundation's bibliography now boasts over 530 articles with "Extensive Reading" in the title. About 35% of this rich and diverse body of papers were published in the past decade. A meta-review of this literature shows it is quite fragmented as evidenced by considerable variability in the conceptualization of…

Adolescent Decision-Making Processes regarding University Entry: A Model Incorporating Cultural Orientation, Motivation and Occupational Variables

ERIC Educational Resources Information Center

Jung, Jae Yup

2013-01-01

This study tested a newly developed model of the cognitive decision-making processes of senior high school students related to university entry. The model incorporated variables derived from motivation theory (i.e. expectancy-value theory and the theory of reasoned action), literature on cultural orientation and occupational considerations. A…

Regression and Geostatistical Techniques: Considerations and Observations from Experiences in NE-FIA

Treesearch

Rachel Riemann; Andrew Lister

2005-01-01

Maps of forest variables improve our understanding of the forest resource by allowing us to view and analyze it spatially. The USDA Forest Service's Northeastern Forest Inventory and Analysis unit (NE-FIA) has used geostatistical techniques, particularly stochastic simulation, to produce maps and spatial data sets of FIA variables. That work underscores the...

Variables and Methodological Considerations Associated with Children's Sex Role Preferences.

ERIC Educational Resources Information Center

Cappella, Roseann

Several key variables in the development and assessment of young children's sex role preference are examined in this study. A sample of 257 pre-kindergarten children (mean age, 59 months) and their mothers participated in this study. After obtaining information on each child's age, IQ, and his/her mother's employment status the It Scale for…

Does children's energy intake at one meal influence their intake at subsequent meals? Or do we just think it does?

PubMed

Hanley, James A; Hutcheon, Jennifer A

2010-05-01

It is widely believed that young children are able to adjust their energy intake across successive meals to compensate for higher or lower intakes at a given meal. This conclusion is based on past observations that although children's intake at individual meals is highly variable, total daily intakes are relatively constant. We investigated how much of this reduction in variability could be explained by the statistical phenomenon of the variability of individual components (each meal) always being relatively larger than the variability of their sum (total daily intake), independent of any physiological compensatory mechanism. We calculated, theoretically and by simulation, how variable a child's daily intake would be if there was no correlation between intakes at individual meals. We simulated groups of children with meal/snack intakes and variability in meal/snack intakes based on previously published values. Most importantly, we assumed that there was no correlation between intakes on successive meals. In both approaches, the coefficient of variation of the daily intakes was roughly 15%, considerably less than the 34% for individual meals. Thus, most of the reduction in variability found in past studies was explained without positing strong 'compensation'. Although children's daily energy intakes are indeed considerably less variable than their individual components, this phenomenon was observed even when intakes at each meal were simulated to be totally independent. We conclude that the commonly held belief that young children have a strong physiological compensatory mechanism to adjust intake at one meal based on intake at prior meals is likely to be based on flawed statistical reasoning.

Prioritizing Wetlands for Waterbirds in a Boom and Bust System: Waterbird Refugia and Breeding in the Murray-Darling Basin

PubMed Central

Bino, Gilad; Kingsford, Richard T.; Porter, John

2015-01-01

Dryland rivers have considerable flow variability, producing complex ecosystems, processes, and communities of organisms that vary over space and time. They are also among the more vulnerable of the world’s ecosystems. A key strategy for conservation of dryland rivers is identifying and maintaining key sites for biodiversity conservation, particularly protecting the quantity and quality of flow and flooding regimes. Extreme variability considerably challenges freshwater conservation planning. We systematically prioritised wetlands for waterbirds (simultaneously for 52 species), across about 13.5% of the Murray-Darling Basin (1,061,469 km2), using a 30-year record of systematic aerial surveys of waterbird populations. Nine key wetlands in this area, primarily lakes, floodplains, and swamps, consistently contributed to a representation target (80%) of total abundances of all 52 waterbird species. The long temporal span of our data included dramatic availability (i.e., booms) and scarcity (i.e., busts) of water, providing a unique opportunity to test prioritisation at extremes of variation. These extremes represented periods when waterbirds were breeding or concentrating on refugia, varying wetland prioritisation. In dry years, important wetlands for waterbirds were riverine and lacustrine (12 wetlands) but this changed in wet years to lacustrine and palustrine (8 wetlands). Such variation in ecosystem condition substantially changes the relative importance of individual wetlands for waterbirds during boom and bust phases. Incorporating this variability is necessary for effective conservation of Murray-Darling Basin waterbirds, with considerable generality for other similarly variable systems around the world. PMID:26161652

GIS Applications in Land Management: The Loss of High Quality Land to Development in Central Mississippi from 1987–2002

PubMed Central

Twumasi, Yaw A.; Merem, Edmund C.

2005-01-01

The socio-economic trends and history of Central Mississippi reveal a major rural influence based upon a dependence on agricultural activities as part of the economic engine driving the state’s economy. Yet, in the last several years, the amount of agricultural land in the counties continues to decline. Similar changes in other variables associated with agricultural land use and the continuity of farming in the state have also been changing. Indeed, under the pressure of urban growth, some farmers are forced to use less productive soils or have abandoned the agricultural business. Considering the gravity of the problem and the implications for sustainable development, public concern has increased in the state of Mississippi that urbanization and other factors may be eroding potential farmland. Given the effects of the current trends on the future capacity to produce food items, there are concerns that the growing incidence of farmland loss may also erode the basis for sustainable use of agricultural land, biodiversity and protection of the state’s ecological treasures. Notwithstanding the gravity of these trends, no major effort in the literature has aimed at documenting the incidence of agricultural land loss and the linkages to urbanization in the region of Central Mississippi. What changes have taken place in the size of agricultural land within the counties and what factors are responsible for it? This paper examines the issue of farmland loss in Central Mississippi with a focus at the county level between 1987 and 2002 from a temporal-spatial perspective. In terms of methodology, the paper uses a mixed scale approach based upon the existing literature. Data were drawn from the United States Census databases of Population and Agriculture. This information is analyzed with basic descriptive statistics and GIS with particular attention to the spatial trends at the county level. Results indicate that the counties under consideration have experienced considerable change in the amount of agricultural land and other variables associated with the use of farmland, due to urbanization. With the types of changes occurring, instituting effective policies anchored in sustainability, community participation, and growth management will go a long way in addressing the situation. Other strategies for farmland protection based upon land information inventory and mapping in the region, are also recommended. The paper stands as an update of the existing literature and offers a valuable tool for decision makers within the domain of natural resources management. PMID:16705823

Exploring the Impact of Early Decisions in Variable Ordering for Constraint Satisfaction Problems.

PubMed

Ortiz-Bayliss, José Carlos; Amaya, Ivan; Conant-Pablos, Santiago Enrique; Terashima-Marín, Hugo

2018-01-01

When solving constraint satisfaction problems (CSPs), it is a common practice to rely on heuristics to decide which variable should be instantiated at each stage of the search. But, this ordering influences the search cost. Even so, and to the best of our knowledge, no earlier work has dealt with how first variable orderings affect the overall cost. In this paper, we explore the cost of finding high-quality orderings of variables within constraint satisfaction problems. We also study differences among the orderings produced by some commonly used heuristics and the way bad first decisions affect the search cost. One of the most important findings of this work confirms the paramount importance of first decisions. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. We propose a simple method to improve early decisions of heuristics. By using it, performance of heuristics increases.

Exploring the Impact of Early Decisions in Variable Ordering for Constraint Satisfaction Problems

PubMed Central

Amaya, Ivan

2018-01-01

When solving constraint satisfaction problems (CSPs), it is a common practice to rely on heuristics to decide which variable should be instantiated at each stage of the search. But, this ordering influences the search cost. Even so, and to the best of our knowledge, no earlier work has dealt with how first variable orderings affect the overall cost. In this paper, we explore the cost of finding high-quality orderings of variables within constraint satisfaction problems. We also study differences among the orderings produced by some commonly used heuristics and the way bad first decisions affect the search cost. One of the most important findings of this work confirms the paramount importance of first decisions. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. We propose a simple method to improve early decisions of heuristics. By using it, performance of heuristics increases. PMID:29681923

The turbulent mean-flow, Reynolds-stress, and heat flux equations in mass-averaged dependent variables

NASA Technical Reports Server (NTRS)

Rubesin, M. W.; Rose, W. C.

1973-01-01

The time-dependent, turbulent mean-flow, Reynolds stress, and heat flux equations in mass-averaged dependent variables are presented. These equations are given in conservative form for both generalized orthogonal and axisymmetric coordinates. For the case of small viscosity and thermal conductivity fluctuations, these equations are considerably simpler than the general Reynolds system of dependent variables for a compressible fluid and permit a more direct extension of low speed turbulence modeling to computer codes describing high speed turbulence fields.

A systematic review of cognitive performance in patients with childhood craniopharyngioma.

PubMed

Özyurt, Jale; Müller, Hermann L; Thiel, Christiane M

2015-10-01

Craniopharyngiomas are rare brain tumors of the sellar/suprasellar region, often adversely affecting patients' physical and psychosocial functioning. Until a few years ago, knowledge on cognitive deficits in craniopharyngioma patients was based on little valid evidence, with considerable inconsistencies across studies. Findings from recent research, with partly larger sample sizes, add to existing evidence to provide a more clear and reliable picture. The current review aims to summarize and systemize current findings on cognitive deficits in childhood craniopharyngioma, taking account of patient- and treatment-related variables where possible. Those studies were included that reported results of childhood craniopharyngioma patients tested with formalized neuropsychological tests (irrespective of their age at study, group size ≥10). A systematic assignment of test results to subcomponents of broader cognitive domains (e.g. to specific memory systems and processes) allows for a first comprehensive overview of patterns of spared and impaired cognitive functions. We show that episodic memory recall in particular is impaired, largely sparing other memory components. In accordance with recent knowledge on mammillary function, patients with hypothalamic involvement appear to be at particular risk. Deficits in higher cognitive processes, relying on the integrity of the prefrontal cortex and its subcortical pathways, may also occur, but results are still inconsistent. To gain deeper insight into the pattern of deficits and their association with patient- and treatment-related variables, further multi-site research with larger cohorts is needed.

Myrciaria dubia, an Amazonian fruit: population structure and its implications for germplasm conservation and genetic improvement.

PubMed

Nunes, C F; Setotaw, T A; Pasqual, M; Chagas, E A; Santos, E G; Santos, D N; Lima, C G B; Cançado, G M A

2017-03-22

Myrciaria dubia (camu-camu) is an Amazon tree that produces a tart fruit with high vitamin C content. It is probably the fruit with the highest vitamin C content among all Brazilian fruit crops and it can be used to supplement daily vitamin C dose. This property has attracted the attention of consumers and, consequently, encouraged fruit farmers to produce it. In order to identify and select potential accessions for commercial exploitation and breeding programs, M. dubia has received considerable research attention. The identification and characterization of genetic diversity, as well as identification of the population structure of accessions preserved in germplasm banks are fundamental for the success of any breeding program. The objective of this study was to evaluate the genetic variability of 10 M. dubia populations obtained from the shores of Reis Lake, located in the municipality of Caracaraí, Roraima, Brazil. Fourteen polymorphic inter simple sequence repeat (ISSR) markers were used to study the population genetic diversity, which resulted in 108 identified alleles. Among the 14 primers, GCV, UBC810, and UBC827 produced the highest number of alleles. The study illustrated the suitability and efficiency of ISSR markers to study the genetic diversity of M. dubia accessions. We also revealed the existence of high genetic variability among both accessions and populations that can be exploited in future breeding programs and conservation activities of this species.

Toward the human cellular microRNAome.

PubMed

McCall, Matthew N; Kim, Min-Sik; Adil, Mohammed; Patil, Arun H; Lu, Yin; Mitchell, Christopher J; Leal-Rojas, Pamela; Xu, Jinchong; Kumar, Manoj; Dawson, Valina L; Dawson, Ted M; Baras, Alexander S; Rosenberg, Avi Z; Arking, Dan E; Burns, Kathleen H; Pandey, Akhilesh; Halushka, Marc K

2017-10-01

MicroRNAs are short RNAs that serve as regulators of gene expression and are essential components of normal development as well as modulators of disease. MicroRNAs generally act cell-autonomously, and thus their localization to specific cell types is needed to guide our understanding of microRNA activity. Current tissue-level data have caused considerable confusion, and comprehensive cell-level data do not yet exist. Here, we establish the landscape of human cell-specific microRNA expression. This project evaluated 8 billion small RNA-seq reads from 46 primary cell types, 42 cancer or immortalized cell lines, and 26 tissues. It identified both specific and ubiquitous patterns of expression that strongly correlate with adjacent superenhancer activity. Analysis of unaligned RNA reads uncovered 207 unknown minor strand (passenger) microRNAs of known microRNA loci and 495 novel putative microRNA loci. Although cancer cell lines generally recapitulated the expression patterns of matched primary cells, their isomiR sequence families exhibited increased disorder, suggesting DROSHA- and DICER1-dependent microRNA processing variability. Cell-specific patterns of microRNA expression were used to de-convolute variable cellular composition of colon and adipose tissue samples, highlighting one use of these cell-specific microRNA expression data. Characterization of cellular microRNA expression across a wide variety of cell types provides a new understanding of this critical regulatory RNA species. © 2017 McCall et al.; Published by Cold Spring Harbor Laboratory Press.

Design Life Level: Quantifying risk in a changing climate

NASA Astrophysics Data System (ADS)

Rootzén, Holger; Katz, Richard W.

2013-09-01

In the past, the concepts of return levels and return periods have been standard and important tools for engineering design. However, these concepts are based on the assumption of a stationary climate and do not apply to a changing climate, whether local or global. In this paper, we propose a refined concept, Design Life Level, which quantifies risk in a nonstationary climate and can serve as the basis for communication. In current practice, typical hydrologic risk management focuses on a standard (e.g., in terms of a high quantile corresponding to the specified probability of failure for a single year). Nevertheless, the basic information needed for engineering design should consist of (i) the design life period (e.g., the next 50 years, say 2015-2064); and (ii) the probability (e.g., 5% chance) of a hazardous event (typically, in the form of the hydrologic variable exceeding a high level) occurring during the design life period. Capturing both of these design characteristics, the Design Life Level is defined as an upper quantile (e.g., 5%) of the distribution of the maximum value of the hydrologic variable (e.g., water level) over the design life period. We relate this concept and variants of it to existing literature and illustrate how they, and some useful complementary plots, may be computed and used. One practically important consideration concerns quantifying the statistical uncertainty in estimating a high quantile under nonstationarity.

Variable ligand- and receptor-binding hot spots in key strains of influenza neuraminidase

PubMed Central

Votapka, Lane; Demir, Özlem; Swift, Robert V; Walker, Ross C; Amaro, Rommie E

2012-01-01

Influenza A continues to be a major public health concern due to its ability to cause epidemic and pandemic disease outbreaks in humans. Computational investigations of structural dynamics of the major influenza glycoproteins, especially the neuraminidase (NA) enzyme, are able to provide key insights beyond what is currently accessible with standard experimental techniques. In particular, all-atom molecular dynamics simulations reveal the varying degrees of flexibility for such enzymes. Here we present an analysis of the relative flexibility of the ligand- and receptor-binding area of three key strains of influenza A: highly pathogenic H5N1, the 2009 pandemic H1N1, and a human N2 strain. Through computational solvent mapping, we investigate the various ligand- and receptor-binding “hot spots” that exist on the surface of NA which interacts with both sialic acid receptors on the host cells and antiviral drugs. This analysis suggests that the variable cavities found in the different strains and their corresponding capacities to bind ligand functional groups may play an important role in the ability of NA to form competent reaction encounter complexes with other species of interest, including antiviral drugs, sialic acid receptors on the host cell surface, and the hemagglutinin protein. Such considerations may be especially useful for the prediction of how such complexes form and with what binding capacity. PMID:22872804

Using statistical and artificial neural network models to forecast potentiometric levels at a deep well in South Texas

NASA Astrophysics Data System (ADS)

Uddameri, V.

2007-01-01

Reliable forecasts of monthly and quarterly fluctuations in groundwater levels are necessary for short- and medium-term planning and management of aquifers to ensure proper service of seasonal demands within a region. Development of physically based transient mathematical models at this time scale poses considerable challenges due to lack of suitable data and other uncertainties. Artificial neural networks (ANN) possess flexible mathematical structures and are capable of mapping highly nonlinear relationships. Feed-forward neural network models were constructed and trained using the back-percolation algorithm to forecast monthly and quarterly time-series water levels at a well that taps into the deeper Evangeline formation of the Gulf Coast aquifer in Victoria, TX. Unlike unconfined formations, no causal relationships exist between water levels and hydro-meteorological variables measured near the vicinity of the well. As such, an endogenous forecasting model using dummy variables to capture short-term seasonal fluctuations and longer-term (decadal) trends was constructed. The root mean square error, mean absolute deviation and correlation coefficient ( R) were noted to be 1.40, 0.33 and 0.77 m, respectively, for an evaluation dataset of quarterly measurements and 1.17, 0.46, and 0.88 m for an evaluative monthly dataset not used to train or test the model. These statistics were better for the ANN model than those developed using statistical regression techniques.

A Hybrid Model for Spatially and Temporally Resolved Ozone Exposures in the Continental United States

PubMed Central

Di, Qian; Rowland, Sebastian; Koutrakis, Petros; Schwartz, Joel

2017-01-01

Ground-level ozone is an important atmospheric oxidant, which exhibits considerable spatial and temporal variability in its concentration level. Existing modeling approaches for ground-level ozone include chemical transport models, land-use regression, Kriging, and data fusion of chemical transport models with monitoring data. Each of these methods has both strengths and weaknesses. Combining those complementary approaches could improve model performance. Meanwhile, satellite-based total column ozone, combined with ozone vertical profile, is another potential input. We propose a hybrid model that integrates the above variables to achieve spatially and temporally resolved exposure assessments for ground-level ozone. We used a neural network for its capacity to model interactions and nonlinearity. Convolutional layers, which use convolution kernels to aggregate nearby information, were added to the neural network to account for spatial and temporal autocorrelation. We trained the model with AQS 8-hour daily maximum ozone in the continental United States from 2000 to 2012 and tested it with left out monitoring sites. Cross-validated R2 on the left out monitoring sites ranged from 0.74 to 0.80 (mean 0.76) for predictions on 1 km×1 km grid cells, which indicates good model performance. Model performance remains good even at low ozone concentrations. The prediction results facilitate epidemiological studies to assess the health effect of ozone in the long term and the short term. PMID:27332675

A mathematical model captures the structure of subjective affect

PubMed Central

Mattek, Alison M.; Wolford, George; Whalen, Paul J.

2016-01-01

While it is possible to observe when another person is having an emotional moment, we also derive information about the affective states of others from what they tell us they are feeling. In an effort to distill the complexity of affective experience, psychologists routinely focus on a simplified subset of subjective rating scales (i.e., dimensions) that capture considerable variability in reported affect: reported valence (i.e., how good or bad?) and reported arousal (e.g., how strong is the emotion you are feeling?). Still, existing theoretical approaches address the basic organization and measurement of these affective dimensions differently. Some approaches organize affect around the dimensions of bipolar valence and arousal (e.g., the circumplex model; Russell, 1980), whereas alternative approaches organize affect around the dimensions of unipolar positivity and unipolar negativity (e.g., the bivariate evaluative model; Cacioppo & Berntson, 1994). In this report, we (1) replicate the data structure observed when collected according to the two approaches described above, and re-interpret these data to suggest that the relationship between each pair of affective dimensions is conditional on valence ambiguity; then (2) formalize this structure with a mathematical model depicting a valence ambiguity dimension that decreases in range as arousal decreases (a triangle). This model captures variability in affective ratings better than alternative approaches, increasing variance explained from ~60% to over 90% without adding parameters. PMID:28544868

Goals and Objectives to Optimize the Value of an Acute Pain Service in Perioperative Pain Management.

PubMed

Le-Wendling, Linda; Glick, Wesley; Tighe, Patrick

2017-12-01

As newer pharmacologic and procedural interventions, technology, and data on outcomes in pain management are becoming available, effective acute pain management will require a dedicated Acute Pain Service (APS) to help determine the most optimal pain management plan for the patients. Goals for pain management must take into consideration the side effect profile of drugs and potential complications of procedural interventions. Multiple objective optimization is the combination of multiple different objectives for acute pain management. Simple use of opioids, for example, can reduce all pain to minimal levels, but at what cost to the patient, the medical system, and to public health as a whole? Many models for APS exist based on personnel's skills, knowledge and experience, but effective use of an APS will also require allocation of time, space, financial, and personnel resources with clear objectives and a feedback mechanism to guide changes to acute pain medicine practices to meet the constantly evolving medical field. Physician-based practices have the advantage of developing protocols for the management of low-variability, high-occurrence scenarios in addition to tailoring care to individual patients with high-variability, low-occurrence scenarios. Frequent feedback and data collection/assessment on patient outcomes is essential in evaluating the efficacy of the Acute Pain Service's intervention in improving patient outcomes in the acute and perioperative setting.

Measurement of breast density with digital breast tomosynthesis—a systematic review

PubMed Central

McEntee, M F

2014-01-01

Digital breast tomosynthesis (DBT) has gained acceptance as an adjunct to digital mammography in screening. Now that breast density reporting is mandated in several states in the USA, it is increasingly important that the methods of breast density measurement be robust, reliable and consistent. Breast density assessment with DBT needs some consideration since quantitative methods are modelled for two-dimensional (2D) mammography. A review of methods used for breast density assessment with DBT was performed. Existing evidence shows Cumulus has better reproducibility than that of the breast imaging reporting and data system (BI-RADS®) but still suffers from subjective variability; MedDensity is limited by image noise, whilst Volpara and Quantra are robust and consistent. The reported BI-RADs inter-reader breast density agreement (k) ranged from 0.65 to 0.91, with inter-reader correlation (r) ranging from 0.70 to 0.93. The correlation (r) between BI-RADS and Cumulus ranged from 0.54–0.94, whilst that of BI-RADs and MedDensity ranged from 0.48–0.78. The reported agreement (k) between BI-RADs and Volpara is 0.953. Breast density correlation between DBT and 2D mammography ranged from 0.73 to 0.97, with agreement (k) ranging from 0.56 to 0.96. To avoid variability and provide more reliable breast density information for clinicians, automated volumetric methods are preferred. PMID:25146640

Seasonal Patterns of the Insect Community Structure in Urban Rain Pools of Temperate Argentina

PubMed Central

Fontanarrosa, M. Soledad; Collantes, Marta B.; Bachmann, Axel O.

2009-01-01

Temporary aquatic environments are widespread in the world, and although there are considerable regional differences in their type and method of formation they have many physical, chemical and biological properties in common. With the aim to increase knowledge of urban temporary pool fauna, the objectives of this work were to assess the seasonal patterns of species composition, richness, and diversity of the aquatic insect community inhabiting rain pools in urban temperate Argentina, and to identify the environmental variables associated to these patterns. Four temporary pools of an urban green space in Buenos Aires City were studied throughout a 1-year period. Eleven flood cycles with very varied hydroperiods and dry periods, mainly associated with rainfall, were identified. Insect species richness in these temporary urban pools, 86 taxa were documented, was found to be within the range reported for wild temporary water bodies of other regions of the world. The present results provide evidence for the existence of a clear link between habitat and community variability. Hydroperiod and seasonality were the main environmental factors involved in structuring the insect communities of the studied water bodies. Urban pools in green spaces have the potential to act to its dwellers like corridors through the urban matrix. Taking into account these characteristics and their accessibility, urban temporary pools can be considered as promising habitats for the study of ecological processes involving the insect community. PMID:19611261

Crop yields response to water pressures in the Ebro basin in Spain: risk and water policy implications

NASA Astrophysics Data System (ADS)

Quiroga, S.; Fernández-Haddad, Z.; Iglesias, A.

2011-02-01

The increasing pressure on water systems in the Mediterranean enhances existing water conflicts and threatens water supply for agriculture. In this context, one of the main priorities for agricultural research and public policy is the adaptation of crop yields to water pressures. This paper focuses on the evaluation of hydrological risk and water policy implications for food production. Our methodological approach includes four steps. For the first step, we estimate the impacts of rainfall and irrigation water on crop yields. However, this study is not limited to general crop production functions since it also considers the linkages between those economic and biophysical aspects which may have an important effect on crop productivity. We use statistical models of yield response to address how hydrological variables affect the yield of the main Mediterranean crops in the Ebro river basin. In the second step, this study takes into consideration the effects of those interactions and analyzes gross value added sensitivity to crop production changes. We then use Montecarlo simulations to characterize crop yield risk to water variability. Finally we evaluate some policy scenarios with irrigated area adjustments that could cope in a context of increased water scarcity. A substantial decrease in irrigated land, of up to 30% of total, results in only moderate losses of crop productivity. The response is crop and region specific and may serve to prioritise adaptation strategies.

Risk of water scarcity and water policy implications for crop production in the Ebro Basin in Spain

NASA Astrophysics Data System (ADS)

Quiroga, S.; Fernández-Haddad, Z.; Iglesias, A.

2010-08-01

The increasing pressure on water systems in the Mediterranean enhances existing water conflicts and threatens water supply for agriculture. In this context, one of the main priorities for agricultural research and public policy is the adaptation of crop yields to water pressures. This paper focuses on the evaluation of hydrological risk and water policy implications for food production. Our methodological approach includes four steps. For the first step, we estimate the impacts of rainfall and irrigation water on crop yields. However, this study is not limited to general crop production functions since it also considers the linkages between those economic and biophysical aspects which may have an important effect on crop productivity. We use statistical models of yield response to address how hydrological variables affect the yield of the main Mediterranean crops in the Ebro River Basin. In the second step, this study takes into consideration the effects of those interactions and analyzes gross value added sensitivity to crop production changes. We then use Montecarlo simulations to characterize crop yield risk to water variability. Finally we evaluate some policy scenarios with irrigated area adjustments that could cope in a context of increased water scarcity. A substantial decrease in irrigated land, of up to 30% of total, results in only moderate losses of crop productivity. The response is crop and region specific and may serve to prioritise adaptation strategies.

[Environmental and demographic variables associated with psychiatric morbidity in former prisoners of war].

PubMed

Dethienne, F; Donnay, J M

1976-01-01

In this study, present psychiatric morbidity of 100 former prisoners of war is related to 28 environmental and demographic variables grouped in 3 periods: before, during and after WW2. With the exception of the invalidity percentage, all statistically significant relations concern variables of the first two periods. The present results are discussed at the light of former publications by the authors. It appears among others that the age variable has to be taken in consideration in the explanation of psychiatric sequels of captivity, and that the condition "invalid of war" poorly reflects the degree of psychiatric morbidity.

Clarifying Resilience in the Context of Homeland Security

DTIC Science & Technology

2013-03-01

Resilience Is a Complex Adaptive System of Systems ( CASoS ) ....60 4. Resilience Is Experienced and Demonstrated in Different Ways ..60 5. Resilience Is...The inclusion of a resilience module into existing homeland security training programs broadens the practitioner’s knowledge base from a basic level...psychology offer several considerations for the homeland security practitioner. The first consideration maintains that a de -emphasis on the

Robotics in rehabilitation: technology as destiny.

PubMed

Stein, Joel

2012-11-01

Robotic aids for rehabilitation hold considerable promise but have not yet achieved widespread clinical adoption. Barriers to adoption include the limited data on efficacy, the single-purpose design of existing robots, financial considerations, and clinician lack of familiarity with this technology. Although the path forward to clinical adoption may be slow and have several false starts, the labor-saving aspect of robotic technology will ultimately ensure its adoption.

Fuels planning: science synthesis and integration; environmental consequences fact sheet 04: wildlife responses to fuels treatments: key considerations

Treesearch

David Pilliod

2004-01-01

Managers face a difficult task in predicting the effects of fuels treatments on wildlife populations, mostly because information on how animals respond to fuels treatments is scarce or does not exist. This paper discusses key considerations-aspects of an animal's ecology and available information-that, despite the scarcity of information, may make predictions of...

Generic oncology drugs: are they all safe?

PubMed

Yang, Y Tony; Nagai, Sumimasa; Chen, Brian K; Qureshi, Zaina P; Lebby, Akida A; Kessler, Samuel; Georgantopoulos, Peter; Raisch, Dennis W; Sartor, Oliver; Hermanson, Terhi; Kane, Robert C; Hrushesky, William J; Riente, Joshua J; Norris, LeAnn B; Bobolts, Laura R; Armitage, James O; Bennett, Charles L

2016-11-01

Although the availability of generic oncology drugs allows access to contemporary care and reduces costs, there is international variability in the safety of this class of drugs. In this Series paper, we review clinical, policy, safety, and regulatory considerations for generic oncology drugs focusing on the USA, Canada, the European Union (EU), Japan, China, and India. Safety information about generic formulations is reviewed from one agent in each class, for heavy metal drugs (cisplatin), targeted agents (imatinib), and cytotoxic agents (docetaxel). We also review regulatory reports from Japan and the USA, countries with the largest pharmaceutical expenditures. Empirical studies did not identify safety concerns in the USA, Canada, the EU, and Japan, where regulations and enforcement are strong. Although manufacturing problems for generic pharmaceuticals exist in India, where 40% of all generic pharmaceuticals used in the USA are manufactured, increased inspections and communication by the US Food and Drug Administration are occurring, facilitating oversight and enforcement. No safety outbreaks among generic oncology drugs were reported in developed countries. For developing countries, oversight is less intensive, and concerns around drug safety still exist. Regulatory agencies should collaboratively develop procedures to monitor the production, shipment, storage, and post-marketing safety of generic oncology drugs. Regulatory agencies for each country should also aim towards identical definitions of bioequivalence, the cornerstone of regulatory approval. Copyright © 2016 Elsevier Ltd. All rights reserved.

Scheduler Design Criteria: Requirements and Considerations

NASA Technical Reports Server (NTRS)

Lee, Hanbong

2016-01-01

This presentation covers fundamental requirements and considerations for developing schedulers in airport operations. We first introduce performance and functional requirements for airport surface schedulers. Among various optimization problems in airport operations, we focus on airport surface scheduling problem, including runway and taxiway operations. We then describe a basic methodology for airport surface scheduling such as node-link network model and scheduling algorithms previously developed. Next, we explain how to design a mathematical formulation in more details, which consists of objectives, decision variables, and constraints. Lastly, we review other considerations, including optimization tools, computational performance, and performance metrics for evaluation.

75 FR 7628 - Davis-Besse Nuclear Power Station; Notice of Consideration of Issuance of Amendment to Facility...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-22

... potential primary water stress corrosion cracking (PWSCC) of the existing welds. These welds provide a... application of a PWSCC resistant weld overlay that has the added benefit of producing compressive stresses on the inner portion of the existing welds. Acceptable residual stresses for purposes of satisfying this...

Measure Guideline. Wood Window Repair, Rehabilitation, and Replacement

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

Baker, P.; Eng, P.

2012-12-01

This measure guideline provides information and guidance on rehabilitating, retrofitting, and replacing existing window assemblies in residential construction. The intent is to provide information regarding means and methods to improve the energy and comfort performance of existing wood window assemblies in a way that takes into consideration component durability, in-service operation, and long term performance of the strategies.

Measure Guideline: Window Repair, Rehabilitation, and Replacement

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

Baker, P.

2012-12-01

This measure guideline provides information and guidance on rehabilitating, retrofitting, and replacing existing window assemblies in residential construction. The intent is to provide information regarding means and methods to improve the energy and comfort performance of existing wood window assemblies in a way that takes into consideration component durability, in-service operation, and long term performance of the strategies.

The Relationships among Shyness, Shame, and Attachment Style with Respect to College Student Persistence and Grade Point Average

ERIC Educational Resources Information Center

Lamana Finn, Kim

2017-01-01

The purpose of this study was to investigate the relationships between attachment style, shyness, shame, and college persistence and grade point average. While considerable research was conducted to examine these variables in children, less is known about how these variables interact in a college setting. This study used a quantitative,…

Tense Marking in Black English. A Linguistic and Social Analysis. Urban Language Series, No. 8.

ERIC Educational Resources Information Center

Fasold, Ralph W.

In recent years a considerable amount of interest has developed in language variability and in the educational problems connected with it. This volume is a report of linguistic research on the variable language behavior in a community of American English speakers, specifically on some aspects of tense marking in Black English. The following topics…

Topography and climate are more important drivers of long-term, post-fire vegetation assembly than time-since-fire in the Sonoran Desert, US

USGS Publications Warehouse

Shryock, Daniel F.; Esque, Todd C.; Chen, Felicia

2015-01-01

We find substantial evidence that environmental filters, rather than TSF, drive the majority of variability in long-term, post-fire vegetation assembly within the Sonoran Desert. Careful consideration of spatial variability in abiotic conditions may benefit post-fire vegetation modelling, as well as fire management and restoration strategies.

Psychological Well-Being of Mothers of Youth with Fragile X Syndrome: Syndrome Specificity and within-Syndrome Variability

ERIC Educational Resources Information Center

Lewis, P.; Abbeduto, L.; Murphy, M.; Richmond, E.; Giles, N.; Bruno, L.; Schroeder, S.; Anderson, J.; Orsmond, G.

2006-01-01

Background: Research on parental well-being has focused largely on Down syndrome and autism; however, fragile X syndrome is likely to pose different challenges for parents compared with these other diagnostic conditions. Moreover, there is considerable variability among youth with fragile X syndrome; for example, 25% to 33% of affected youth meet…

Heritability of mandibular cephalometric variables in twins with completed craniofacial growth.

PubMed

Šidlauskas, Mantas; Šalomskienė, Loreta; Andriuškevičiūtė, Irena; Šidlauskienė, Monika; Labanauskas, Žygimantas; Vasiliauskas, Arūnas; Kupčinskas, Limas; Juzėnas, Simonas; Šidlauskas, Antanas

2016-10-01

To determine genetic and environmental impact on mandibular morphology using lateral cephalometric analysis of twins with completed mandibular growth and deoxyribonucleic acid (DNA) based zygosity determination. The 39 cephalometric variables of 141 same gender adult pair of twins were analysed. Zygosity was determined using 15 specific DNA markers and cervical vertebral maturation method was used to assess completion of the mandibular growth. A genetic analysis was performed using maximum likelihood genetic structural equation modelling (GSEM). The genetic heritability estimates of angular variables describing horizontal mandibular position in relationship to cranial base and maxilla were considerably higher than in those describing vertical position. The mandibular skeletal cephalometric variables also showed high heritability estimates with angular measurements being considerably higher than linear ones. Results of this study indicate that the angular measurements representing mandibular skeletal morphology (mandibular form) have greater genetic determination than the linear measurements (mandibular size). The shape and sagittal position of the mandible is under stronger genetic control, than is its size and vertical relationship to cranial base. © The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Psychosocial predictors in consideration of cosmetic surgery among women.

PubMed

Nerini, Amanda; Matera, Camilla; Stefanile, Cristina

2014-04-01

This study aimed to analyze the influence of psychosocial factors on the consideration of cosmetic surgery. The authors hypothesized that the internalization of thin ideals and social comparisons mediate the relationship between media pressure, family and peer influence (appearance conversations, perception of teasing, and peer attributions), and the desire to pursue cosmetic surgery. The study participants were 429 Italian women (mean age, 33 years). They completed a questionnaire containing the Appearance Conversations With Friends Scale, the Perception of Teasing Scale for Friends, the Peer Attribution Scale, the "Pressure and Internalization-General" subscales of the Sociocultural Attitudes Towards Appearance Questionnaire-3, the Feedback on Physical Appearance Scale, the Physical Appearance Comparison Scale, and the "Consider" subscale of the Acceptance of Cosmetic Surgery Scale. Hierarchical linear regression was performed. The results indicated that media pressure and appearance conversations with peers predicted the outcome variable through the full mediation of internalization of thin ideals. The relation between peer attributions and interest in cosmetic surgery was partially mediated by internalization of thin ideals. Although social comparison was significantly related to both sociocultural variables and consideration of cosmetic procedures, it was not a significant mediator of this relationship. Neither family influence nor perception of teasing predicted the outcome variable. Overall, these results provide important information about the factors implicated in the consideration of cosmetic surgery by women. This research confirms that cosmetic surgeons need to adopt a base psychological approach. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Design Development Test and Evaluation (DDT and E) Considerations for Safe and Reliable Human Rated Spacecraft Systems

NASA Technical Reports Server (NTRS)

Miller, James; Leggett, Jay; Kramer-White, Julie

2008-01-01

A team directed by the NASA Engineering and Safety Center (NESC) collected methodologies for how best to develop safe and reliable human rated systems and how to identify the drivers that provide the basis for assessing safety and reliability. The team also identified techniques, methodologies, and best practices to assure that NASA can develop safe and reliable human rated systems. The results are drawn from a wide variety of resources, from experts involved with the space program since its inception to the best-practices espoused in contemporary engineering doctrine. This report focuses on safety and reliability considerations and does not duplicate or update any existing references. Neither does it intend to replace existing standards and policy.

Pascal's wager: combining continuous glucose monitoring and continuous subcutaneous insulin infusion.

PubMed

Kerr, David; Olateju, Tolu

2010-06-01

Pascal's Wager is a suggestion posed by the French Philosopher, Blaise Pascal, that even though the existence of God cannot be determined through reason, a person should wager that God exists because he or she has everything to gain and nothing to lose. In the area of consideration here, the optimum experimental trial of the combined use of continuous subcutaneous insulin infusion and real-time continuous glucose monitoring in free-living individuals with type 1 diabetes providing rock-solid evidence of clinical benefit has not been performed. Nevertheless, there is considerable enthusiasm for combining the technologies among healthcare professionals, patients, and manufacturers based on the belief that this approach to diabetes care must be beneficial beyond the available evidence (i.e., reason).

Defining Operational Space Suit Requirements for Commercial Orbital Spaceflight

NASA Technical Reports Server (NTRS)

Alpert, Brian K.

2015-01-01

As the commercial spaceflight industry transitions from suborbital brevity to orbital outposts, spacewalking will become a major consideration for tourists, scientists, and hardware providers. The challenge exists to develop a space suit designed for the orbital commercial spaceflight industry. The unique needs and requirements of this industry will drive space suit designs and costs that are unlike any existing product. Commercial space tourists will pay for the experience of a lifetime, while scientists may not be able to rely on robotics for all operations and external hardware repairs. This study was aimed at defining space suit operational and functional needs across the spectrum of spacewalk elements, identifying technical design drivers and establishing appropriate options. Recommendations from the analysis are offered for consideration

On The Determination of Shadow Boundaries and Relevant Eigenrays For Sound Propagation In Stratified Moving Media

NASA Technical Reports Server (NTRS)

Mcaninch, Gerry L.; Heath, Stephanie L.

2006-01-01

The eiconal and ray equations for a stratified moving medium are analyzed to determine which rays connect a source located at an altitude z = z(sub s) to an observer on the ground plane. The characteristics of all available rays are ascertained. Further, the rays which determine the shadow boundary are found. Thus, the shadow boundary may be easily calculated and any observers for which an eigenray does not exist eliminated from further consideration. Therefore, the analysis may be applied to save computer time in two ways. First, rays that do not reach the ground may be eliminated before they are traced, and observers for which no eigenray exists may be eliminated from consideration.

Determining the influence and effects of manufacturing variables on sulfur dioxide cells

NASA Technical Reports Server (NTRS)

Zajac, W. V.; Thomas, M. A.; Barnes, J. A.; Bis, R., F.; Davis, P. B.; Debold, F. C.; Gemmill, G. W.; Kowalchik, L. A.

1986-01-01

A survey of the Li/SO2 manufacturing community was conducted to determine where variability exists in processing. The upper and lower limits of these processing variables might, by themselves or by interacting with other variables, influence safety, performance, and reliability. A number of important variables were identified and a comprehensive design experiment is being proposed to make the proper determinations.

The roles of family, culture, and social cognitive variables in the career interests and goals of Asian American college students.

PubMed

Hui, Kayi; Lent, Robert W

2018-01-01

Although family and cultural factors have been assumed to play important roles in the career development of Asian Americans, theory-driven research on this topic remains limited. We examined culturally relevant factors that may contribute to Asian Americans' consideration of fields in which they are overrepresented (e.g., science, technology, engineering) and underrepresented (e.g., education, social science). Drawing from social cognitive career theory, a culture-specific, social cognitive model of career interests and choice was tested in Holland's (1997) Investigative (I) and Social (S) themes. A sample of 802 Asian American undergraduates completed measures of family support, self-efficacy, outcome expectations, interest, and career choice consideration in relation to both Holland themes. Two indicators of acculturation/enculturation (adherence to Asian values and generation status in the United States) were also obtained. The model accounted for a substantial amount of variance in Asian American college students' career consideration in both themes. Family support and acculturation played varying roles, depending on the Holland theme. For example, family support was linked to career choice consideration both directly (in the S theme) and indirectly, via other predictors (in both themes). Contrary to expectations, the acculturation variables did not moderate the relation of family support or interest to career consideration in either theme. We discuss the implications of these findings for efforts to understand and facilitate the career development of Asian American college students. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

[Total knee and hip prosthesis: variables associated with costs].

PubMed

Herrera-Espiñeira, Carmen; Escobar, Antonio; Navarro-Espigares, José Luis; Castillo, Juan de Dios Lunadel; García-Pérez, Lidia; Godoy-Montijano, Amparo

2013-01-01

The elevated prevalence of osteoarthritis in Western countries, the high costs of hip and knee arthroplasty, and the wide variations in the clinical practice have generated considerable interest in comparing the associated costs before and after surgery. To determine the influence of a number of variables on the costs of total knee and hip arthroplasty surgery during the hospital stay and during the one-year post-discharge. A prospective multi-center study was performed in 15 hospitals from three Spanish regions. Relationships between the independent variables and the costs of hospital stay and postdischarge follow-up were analyzed by using multilevel models in which the "hospital" variable was used to group cases. Independent variables were: age, sex, body mass index, preoperative quality of life (SF-12, EQ-5 and Womac questionnaires), surgery (hip/knee), Charlson Index, general and local complications, number of beds and economic-institutional dependency of the hospital, the autonomous region to which it belongs, and the presence of a caregiver. The cost of hospital stay, excluding the cost of the prosthesis, was 4,734 Euros, and the post-discharge cost was 554 Euros. With regard to hospital stay costs, the variance among hospitals explained 44-46% of the total variance among the patients. With regard to the post-discharge costs, the variability among hospitals explained 7-9% of the variance among the patients. There is considerable potential for reducing the hospital stay costs of these patients, given that more than 44% of the observed variability was not determined by the clinical conditions of the patients but rather by the behavior of the hospitals.

A Conceptual Approach to the Problem of Action-Angle Variables

NASA Astrophysics Data System (ADS)

Zung, Nguyen Tien

2018-02-01

In this paper we develop a general conceptual approach to the problem of existence of action-angle variables for dynamical systems, which establishes and uses the fundamental conservation property of associated torus actions: anything which is preserved by the system is also preserved by the associated torus actions. This approach allows us to obtain, among other things: (a) the shortest and most easy-to-understand conceptual proof of the classical Arnold-Liouville-Mineur theorem; (b) basically all known results in the literature about the existence of action-angle variables in various contexts can be recovered in a unifying way, with simple proofs, using our approach; (c) new results on action-angle variables in many different contexts, including systems on contact manifolds, systems on presymplectic and Dirac manifolds, action-angle variables near singularities, stochastic systems, and so on. Even when there are no natural action variables, our approach still leads to useful normal forms for dynamical systems, which are not necessarily integrable.

Sizing ocean giants: patterns of intraspecific size variation in marine megafauna

PubMed Central

Balk, Meghan A.; Benfield, Mark C.; Branch, Trevor A.; Chen, Catherine; Cosgrove, James; Dove, Alistair D.M.; Gaskins, Lindsay C.; Helm, Rebecca R.; Hochberg, Frederick G.; Lee, Frank B.; Marshall, Andrea; McMurray, Steven E.; Schanche, Caroline; Stone, Shane N.; Thaler, Andrew D.

2015-01-01

What are the greatest sizes that the largest marine megafauna obtain? This is a simple question with a difficult and complex answer. Many of the largest-sized species occur in the world’s oceans. For many of these, rarity, remoteness, and quite simply the logistics of measuring these giants has made obtaining accurate size measurements difficult. Inaccurate reports of maximum sizes run rampant through the scientific literature and popular media. Moreover, how intraspecific variation in the body sizes of these animals relates to sex, population structure, the environment, and interactions with humans remains underappreciated. Here, we review and analyze body size for 25 ocean giants ranging across the animal kingdom. For each taxon we document body size for the largest known marine species of several clades. We also analyze intraspecific variation and identify the largest known individuals for each species. Where data allows, we analyze spatial and temporal intraspecific size variation. We also provide allometric scaling equations between different size measurements as resources to other researchers. In some cases, the lack of data prevents us from fully examining these topics and instead we specifically highlight these deficiencies and the barriers that exist for data collection. Overall, we found considerable variability in intraspecific size distributions from strongly left- to strongly right-skewed. We provide several allometric equations that allow for estimation of total lengths and weights from more easily obtained measurements. In several cases, we also quantify considerable geographic variation and decreases in size likely attributed to humans. PMID:25649000

An approach toward incorporation of global warming effects into Intensity-Duration-Frequency values

NASA Astrophysics Data System (ADS)

Kunkel, K.; Easterling, D. R.

2017-12-01

Rising global temperatures from increasing greenhouse gas concentrations will increase overall atmospheric water vapor concentrations. There is a high level of scientific confidence that this will increase the future intensity and frequency of extreme precipitation events, even in regions where overall precipitation may decrease. For control of runoff from extreme rainfall, infrastructure engineering utilizes design values of rainfall known as Intensity-Duration-Frequency (IDF) values. Use of the existing IDF values, which are based solely on historical climate records, is likely to lead to under-design of runoff control structures, and associated increased flood damages. However, future changes in IDF values are uncertain and probably regionally variable. Our paradigm is that changes in IDF values will result from changes in atmospheric capacity (water vapor concentrations) and opportunity (the number and intensity of heavy precipitation-producing storm systems). Relevant storm systems being investigated include extratropical cyclones and their associated fronts, tropical cyclones, and the North American Monsoon system. The overall approach involves developing IDF adjustment factors for changes in these components of the climate system. The adjustment factors have associated uncertainties, primarily from (1) uncertainties in the future pathway of greenhouse gas emissions and (2) variations among climate models in the sensitivity of the climate system to greenhouse gas concentration changes. In addition to meteorological considerations, the lifetime of projects designed using IDF values is an essential consideration because the IDF values may change substantially during that time. The initial results of this project will be discussed.

Development of an integrated BEM approach for hot fluid structure interaction: BEST-FSI: Boundary Element Solution Technique for Fluid Structure Interaction

NASA Technical Reports Server (NTRS)

Dargush, G. F.; Banerjee, P. K.; Shi, Y.

1992-01-01

As part of the continuing effort at NASA LeRC to improve both the durability and reliability of hot section Earth-to-orbit engine components, significant enhancements must be made in existing finite element and finite difference methods, and advanced techniques, such as the boundary element method (BEM), must be explored. The BEM was chosen as the basic analysis tool because the critical variables (temperature, flux, displacement, and traction) can be very precisely determined with a boundary-based discretization scheme. Additionally, model preparation is considerably simplified compared to the more familiar domain-based methods. Furthermore, the hyperbolic character of high speed flow is captured through the use of an analytical fundamental solution, eliminating the dependence of the solution on the discretization pattern. The price that must be paid in order to realize these advantages is that any BEM formulation requires a considerable amount of analytical work, which is typically absent in the other numerical methods. All of the research accomplishments of a multi-year program aimed toward the development of a boundary element formulation for the study of hot fluid-structure interaction in Earth-to-orbit engine hot section components are detailed. Most of the effort was directed toward the examination of fluid flow, since BEM's for fluids are at a much less developed state. However, significant strides were made, not only in the analysis of thermoviscous fluids, but also in the solution of the fluid-structure interaction problem.

Constraining past seawater δ18O and temperature records developed from foraminiferal geochemistry

NASA Astrophysics Data System (ADS)

Quinn, T. M.; Thirumalai, K.; Marino, G.

2016-12-01

Paired measurements of magnesium-to-calcium ratios (Mg/Ca) and the stable oxygen isotopic composition (δ18O) in foraminifera have significantly advanced our knowledge of the climate system by providing information on past temperature and seawater δ18O (δ18Osw, a proxy for salinity and ice volume). However, multiple sources of uncertainty exist in transferring these downcore geochemical data into quantitative paleoclimate reconstructions. Here, we develop a computational toolkit entitled Paleo-Seawater Uncertainty Solver (PSU Solver) that performs bootstrap Monte Carlo simulations to constrain these various sources of uncertainty. PSU Solver calculates temperature and δ18Osw, and their respective confidence intervals using an iterative approach with user-defined errors, calibrations, and sea-level curves. Our probabilistic approach yields reduced uncertainty constraints compared to theoretical considerations and commonly used propagation exercises. We demonstrate the applicability of PSU Solver for published records covering three timescales: the late Holocene, the last deglaciation, and the last glacial period. We show that the influence of salinity on Mg/Ca can considerably alter the structure and amplitude of change in the resulting reconstruction and can impact the interpretation of paleoceanographic time series. We also highlight the sensitivity of the records to various inputs of sea-level curves, transfer functions, and uncertainty constraints. PSU Solver offers an expeditious yet rigorous approach to test the robustness of past climate variability inferred from paired Mg/Ca-δ18O measurements.

Estimating verbal fluency and naming ability from the test of premorbid functioning and demographic variables: Regression equations derived from a regional UK sample.

PubMed

Jenkinson, Toni-Marie; Muncer, Steven; Wheeler, Miranda; Brechin, Don; Evans, Stephen

2018-06-01

Neuropsychological assessment requires accurate estimation of an individual's premorbid cognitive abilities. Oral word reading tests, such as the test of premorbid functioning (TOPF), and demographic variables, such as age, sex, and level of education, provide a reasonable indication of premorbid intelligence, but their ability to predict other related cognitive abilities is less well understood. This study aimed to develop regression equations, based on the TOPF and demographic variables, to predict scores on tests of verbal fluency and naming ability. A sample of 119 healthy adults provided demographic information and were tested using the TOPF, FAS, animal naming test (ANT), and graded naming test (GNT). Multiple regression analyses, using the TOPF and demographics as predictor variables, were used to estimate verbal fluency and naming ability test scores. Change scores and cases of significant impairment were calculated for two clinical samples with diagnosed neurological conditions (TBI and meningioma) using the method in Knight, McMahon, Green, and Skeaff (). Demographic variables provided a significant contribution to the prediction of all verbal fluency and naming ability test scores; however, adding TOPF score to the equation considerably improved prediction beyond that afforded by demographic variables alone. The percentage of variance accounted for by demographic variables and/or TOPF score varied from 19 per cent (FAS), 28 per cent (ANT), and 41 per cent (GNT). Change scores revealed significant differences in performance in the clinical groups, particularity the TBI group. Demographic variables, particularly education level, and scores on the TOPF should be taken into consideration when interpreting performance on tests of verbal fluency and naming ability. © 2017 The British Psychological Society.

To Cull or Not To Cull? Considerations for Studies of Endocrine-Disrupting Chemicals.

PubMed

Suvorov, Alexander; Vandenberg, Laura N

2016-07-01

The power of animal models is derived from the ability to control experimental variables so that observed effects may be unequivocally attributed to the factor that was changed. One variable that is difficult to control in animal experiments is the number and composition of offspring in a litter. To account for this variability, artificial equalization of the number of offspring in a litter (culling) is often used. The rationale for culling, however, has always been controversial. The Developmental Origins of Health and Disease concept provides a new context to evaluate the pros and cons of culling in laboratory animal studies, especially in the context of endocrine-disrupting chemicals. Emerging evidence indicates that culling, especially of large litters, can drastically change the feeding status of a pup, which can result in compensatory growth with long-term consequences for the animal, including increased risk of cardio-metabolic diseases. Similarly, culling of litters to intentionally bias sex ratios can alter the animal's behavior and physiology, with effects observed on a wide range of outcomes. Thus, in an attempt to control for variability in developmental rates, culling introduces an uncontrolled or confounding variable, which itself may affect a broad spectrum of health-related consequences. Variabilities in culling protocols could be responsible for differences in responses to endocrine-disrupting chemicals reported across studies. Because litter sex composition and size are vectors that can influence both prenatal and postnatal growth, they are essential considerations for the interpretation of results from laboratory animal studies.

A Bell-type theorem without hidden variables

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

Stapp, Henry P.

2003-09-12

It is shown that no theory that satisfies certain premises can exclude faster-than-light influences. The premises include neither the existence of hidden variables nor counterfactual definiteness, nor any premise that effectively entails the general existence of outcomes of unperformed local measurements. All the premises are compatible with Copenhagen philosophy and the principles and predictions of relativistic quantum field theory. The present proof is contrasted with an earlier one with the same objective.

Intraindividual variability as an indicator of malingering in head injury.

PubMed

Strauss, Esther; Slick, Daniel J; Levy-Bencheton, Judi; Hunter, Michael; MacDonald, Stuart W S; Hultsch, David F

2002-07-01

The utility of various measures of malingering was evaluated using an analog design in which half the participants (composed of three groups: naive healthy people, professionals working with head-injured people, individuals who suffered a head injury but not currently in litigation) were asked to try their best and the remainder was asked to feign believable injury. Participants were assessed with the Reliable Digit Span (RDS) task, the Victoria Symptom Validity Test (VSVT), and the Computerized Dot Counting Test (CDCT) on three separate occasions in order to determine whether repeat administration of tests improves prediction. The results indicated that regardless of an individual's experience, consideration of both level of performance (particularly on forced-choice symptom validity tasks) and intraindividual variability holds considerable promise for the detection of malingering.

Performance evaluation on cool roofs for green remodeling

NASA Astrophysics Data System (ADS)

Yun, Yosun; Cho, Dongwoo; Cho, Kyungjoo

2018-06-01

Cool roofs refer that maximize heat emission, and minimize the absorption of solar radiation energy, by applying high solar reflectance paints, or materials to roofs or rooftops. The application of cool roofs to existing buildings does not need to take structural issues into consideration, as rooftop greening, is an alternative that can be applied to existing buildings easily. This study installed a cool roofs on existing buildings, and evaluated the performances, using the results to propose certification standards for green remodeling, considering the cool roof-related standards.

Evaluation of oral hygiene products: science is true; don't be misled by the facts.

PubMed

Addy, M; Moran, J M

1997-10-01

Most people in industrialized countries use oral hygiene products. When an oral health benefit is expected, it is important that sufficient scientific evidence exist to support such claims. Ideally, data should be cumulative derived from studies in vitro and in vivo. The data should be available to the profession for evaluation by publication in refereed scientific journals. Terms and phrases require clarification, and claims made by implication or derived by inference must be avoided. Similarity in products is not necessarily proof per se of efficacy. Studies in vitro and in vivo should follow the basic principles of scientific research. Studies must be ethical, avoid bias and be suitably controlled. A choice of controls will vary depending on whether an agent or a whole product is evaluated and the development stage of a formulation. Where appropriate, new products should be compared with products already available and used by the general public. Conformity with the guidelines for good clinical practice appears to be a useful way of validating studies and a valuable guide to the profession. Studies should be designed with sufficient power to detect statistically significant differences if these exist. However, consideration must be given to the clinical significance of statistically significant differences between formulations since these are not necessarily the same. Studies in vitro provide supportive data but extrapolation to clinical effect is difficult and even misleading, and such data should not stand alone as proof of efficacy of a product. Short-term studies in vivo provide useful information, particularly at the development stage. Ideally, however, products should be proved effective when used in the circumstances for which they are developed. Nevertheless, a variety of variable influence the outcome of home-use studies, and the influence of the variable cannot usually be calculated. Although rarely considered, the cost-benefit ratio of some oral hygiene products needs to be considered.

Comparing lumbo-pelvic kinematics in people with and without back pain: a systematic review and meta-analysis

PubMed Central

2014-01-01

Background Clinicians commonly examine posture and movement in people with the belief that correcting dysfunctional movement may reduce pain. If dysfunctional movement is to be accurately identified, clinicians should know what constitutes normal movement and how this differs in people with low back pain (LBP). This systematic review examined studies that compared biomechanical aspects of lumbo-pelvic movement in people with and without LBP. Methods MEDLINE, Cochrane Central, EMBASE, AMI, CINAHL, Scopus, AMED, ISI Web of Science were searched from inception until January 2014 for relevant studies. Studies had to compare adults with and without LBP using skin surface measurement techniques to measure lumbo-pelvic posture or movement. Two reviewers independently applied inclusion and exclusion criteria, and identified and extracted data. Standardised mean differences and 95% confidence intervals were estimated for group differences between people with and without LBP, and where possible, meta-analyses were performed. Within-group variability in all measurements was also compared. Results The search identified 43 eligible studies. Compared to people without LBP, on average, people with LBP display: (i) no difference in lordosis angle (8 studies), (ii) reduced lumbar ROM (19 studies), (iii) no difference in lumbar relative to hip contribution to end-range flexion (4 studies), (iv) no difference in standing pelvic tilt angle (3 studies), (v) slower movement (8 studies), and (vi) reduced proprioception (17 studies). Movement variability appeared greater for people with LBP for flexion, lateral flexion and rotation ROM, and movement speed, but not for other movement characteristics. Considerable heterogeneity exists between studies, including a lack of detail or standardization between studies on the criteria used to define participants as people with LBP (cases) or without LBP (controls). Conclusions On average, people with LBP have reduced lumbar ROM and proprioception, and move more slowly compared to people without LBP. Whether these deficits exist prior to LBP onset is unknown. PMID:25012528

Evidence for multiple stressor interactions and effects on coral reefs.

PubMed

Ban, Stephen S; Graham, Nicholas A J; Connolly, Sean R

2014-03-01

Concern is growing about the potential effects of interacting multiple stressors, especially as the global climate changes. We provide a comprehensive review of multiple stressor interactions in coral reef ecosystems, which are widely considered to be one of the most sensitive ecosystems to global change. First, we synthesized coral reef studies that examined interactions of two or more stressors, highlighting stressor interactions (where one stressor directly influences another) and potentially synergistic effects on response variables (where two stressors interact to produce an effect that is greater than purely additive). For stressor-stressor interactions, we found 176 studies that examined at least 2 of the 13 stressors of interest. Applying network analysis to analyze relationships between stressors, we found that pathogens were exacerbated by more costressors than any other stressor, with ca. 78% of studies reporting an enhancing effect by another stressor. Sedimentation, storms, and water temperature directly affected the largest number of other stressors. Pathogens, nutrients, and crown-of-thorns starfish were the most-influenced stressors. We found 187 studies that examined the effects of two or more stressors on a third dependent variable. The interaction of irradiance and temperature on corals has been the subject of more research (62 studies, 33% of the total) than any other combination of stressors, with many studies reporting a synergistic effect on coral symbiont photosynthetic performance (n = 19). Second, we performed a quantitative meta-analysis of existing literature on this most-studied interaction (irradiance and temperature). We found that the mean effect size of combined treatments was statistically indistinguishable from a purely additive interaction, although it should be noted that the sample size was relatively small (n = 26). Overall, although in aggregate a large body of literature examines stressor effects on coral reefs and coral organisms, considerable gaps remain for numerous stressor interactions and effects, and insufficient quantitative evidence exists to suggest that the prevailing type of stressor interaction is synergistic.

[Some problems of the study and representation of Siberian flora biodiversity in connection with its conservation].

PubMed

Olonova, M V

2007-01-01

The present knowledge of flora of Siberia is quite insufficient, which is a considerable obstacle to the detection of its biodiversity for conserving the gene pool. Planning conservation measures should be focused not only on species, but also on intraspecific taxa and their phylogenetic uniqueness. In the absence of genetic data, available morphological and geographical methods should be used, so that, when it is impossible to establish the actual origin and relationship of taxa, the existing morphological diverstity is at least represented, as far as it is known to be based on genetic diversity. Phenetic maps can be of much use in the study of intraspecific morphological diversity. The estimation of geographic variability and morphological diversity, as well as the evaluation of territories, can be based on such maps. To represent adequately the biodiversity existing within poorly studied, presumably hybrid plant groups, until actual origin and relationship are known, they should probably be forcedly and provisionally considered as a special type of hybrid complexes, representing the unclear present day taxonomic situation. Such complexes could include populations and individuals with morphological characters of two or more different species, until the systematic position of such populations and individuals is further explored. Until the actual taxonomic status and relationship of the components are established, they could be regarded as subspecies permitted by the Code, or as certain recorded morphological deviations from the type, without assigning any taxonomic status to them--depending on the available data on variability and distribution. In the future, the resulting provisional information on morphological diversity would help to concentrate the efforts of biologists, in possession of the newest methods, on the most important objects, and serve as the scientific base for effective measures aimed at the conservation and management of the vast gene pool of the Siberian flora.

A Mixed Integer Efficient Global Optimization Framework: Applied to the Simultaneous Aircraft Design, Airline Allocation and Revenue Management Problem

NASA Astrophysics Data System (ADS)

Roy, Satadru

Traditional approaches to design and optimize a new system, often, use a system-centric objective and do not take into consideration how the operator will use this new system alongside of other existing systems. This "hand-off" between the design of the new system and how the new system operates alongside other systems might lead to a sub-optimal performance with respect to the operator-level objective. In other words, the system that is optimal for its system-level objective might not be best for the system-of-systems level objective of the operator. Among the few available references that describe attempts to address this hand-off, most follow an MDO-motivated subspace decomposition approach of first designing a very good system and then provide this system to the operator who decides the best way to use this new system along with the existing systems. The motivating example in this dissertation presents one such similar problem that includes aircraft design, airline operations and revenue management "subspaces". The research here develops an approach that could simultaneously solve these subspaces posed as a monolithic optimization problem. The monolithic approach makes the problem a Mixed Integer/Discrete Non-Linear Programming (MINLP/MDNLP) problem, which are extremely difficult to solve. The presence of expensive, sophisticated engineering analyses further aggravate the problem. To tackle this challenge problem, the work here presents a new optimization framework that simultaneously solves the subspaces to capture the "synergism" in the problem that the previous decomposition approaches may not have exploited, addresses mixed-integer/discrete type design variables in an efficient manner, and accounts for computationally expensive analysis tools. The framework combines concepts from efficient global optimization, Kriging partial least squares, and gradient-based optimization. This approach then demonstrates its ability to solve an 11 route airline network problem consisting of 94 decision variables including 33 integer and 61 continuous type variables. This application problem is a representation of an interacting group of systems and provides key challenges to the optimization framework to solve the MINLP problem, as reflected by the presence of a moderate number of integer and continuous type design variables and expensive analysis tool. The result indicates simultaneously solving the subspaces could lead to significant improvement in the fleet-level objective of the airline when compared to the previously developed sequential subspace decomposition approach. In developing the approach to solve the MINLP/MDNLP challenge problem, several test problems provided the ability to explore performance of the framework. While solving these test problems, the framework showed that it could solve other MDNLP problems including categorically discrete variables, indicating that the framework could have broader application than the new aircraft design-fleet allocation-revenue management problem.

32 CFR 145.4 - Policy.

Code of Federal Regulations, 2011 CFR

2011-07-01

.... L. 95-454 and of the responsibilities of the Department of Defense. (f) OSC investigative requests involving classified information shall be accorded special attention and prompt consideration under existing...

The existence of semiregular solutions to elliptic spectral problems with discontinuous nonlinearities

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

Pavlenko, V N; Potapov, D K

2015-09-30

This paper is concerned with the existence of semiregular solutions to the Dirichlet problem for an equation of elliptic type with discontinuous nonlinearity and when the differential operator is not assumed to be formally self-adjoint. Theorems on the existence of semiregular (positive and negative) solutions for the problem under consideration are given, and a principle of upper and lower solutions giving the existence of semiregular solutions is established. For positive values of the spectral parameter, elliptic spectral problems with discontinuous nonlinearities are shown to have nontrivial semiregular (positive and negative) solutions. Bibliography: 32 titles.

Comparative assessment of nanomaterial definitions and safety evaluation considerations.

PubMed

Boverhof, Darrell R; Bramante, Christina M; Butala, John H; Clancy, Shaun F; Lafranconi, Mark; West, Jay; Gordon, Steve C

2015-10-01

Nanomaterials continue to bring promising advances to science and technology. In concert have come calls for increased regulatory oversight to ensure their appropriate identification and evaluation, which has led to extensive discussions about nanomaterial definitions. Numerous nanomaterial definitions have been proposed by government, industry, and standards organizations. We conducted a comprehensive comparative assessment of existing nanomaterial definitions put forward by governments to highlight their similarities and differences. We found that the size limits used in different definitions were inconsistent, as were considerations of other elements, including agglomerates and aggregates, distributional thresholds, novel properties, and solubility. Other important differences included consideration of number size distributions versus weight distributions and natural versus intentionally-manufactured materials. Overall, the definitions we compared were not in alignment, which may lead to inconsistent identification and evaluation of nanomaterials and could have adverse impacts on commerce and public perceptions of nanotechnology. We recommend a set of considerations that future discussions of nanomaterial definitions should consider for describing materials and assessing their potential for health and environmental impacts using risk-based approaches within existing assessment frameworks. Our intent is to initiate a dialogue aimed at achieving greater clarity in identifying those nanomaterials that may require additional evaluation, not to propose a formal definition. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Quantitative approaches in climate change ecology

PubMed Central

Brown, Christopher J; Schoeman, David S; Sydeman, William J; Brander, Keith; Buckley, Lauren B; Burrows, Michael; Duarte, Carlos M; Moore, Pippa J; Pandolfi, John M; Poloczanska, Elvira; Venables, William; Richardson, Anthony J

2011-01-01

Contemporary impacts of anthropogenic climate change on ecosystems are increasingly being recognized. Documenting the extent of these impacts requires quantitative tools for analyses of ecological observations to distinguish climate impacts in noisy data and to understand interactions between climate variability and other drivers of change. To assist the development of reliable statistical approaches, we review the marine climate change literature and provide suggestions for quantitative approaches in climate change ecology. We compiled 267 peer-reviewed articles that examined relationships between climate change and marine ecological variables. Of the articles with time series data (n = 186), 75% used statistics to test for a dependency of ecological variables on climate variables. We identified several common weaknesses in statistical approaches, including marginalizing other important non-climate drivers of change, ignoring temporal and spatial autocorrelation, averaging across spatial patterns and not reporting key metrics. We provide a list of issues that need to be addressed to make inferences more defensible, including the consideration of (i) data limitations and the comparability of data sets; (ii) alternative mechanisms for change; (iii) appropriate response variables; (iv) a suitable model for the process under study; (v) temporal autocorrelation; (vi) spatial autocorrelation and patterns; and (vii) the reporting of rates of change. While the focus of our review was marine studies, these suggestions are equally applicable to terrestrial studies. Consideration of these suggestions will help advance global knowledge of climate impacts and understanding of the processes driving ecological change.

Predicting the La Niña of 2020-21: Termination of Solar Cycles and Correlated Variance in Solar and Atmospheric Variability

NASA Astrophysics Data System (ADS)

Leamon, R. J.; McIntosh, S. W.

2017-12-01

Establishing a solid physical connection between solar and tropospheric variability has posed a considerable challenge across the spectrum of Earth-system science. Over the past few years a new picture to describe solar variability has developed, based on observing, understanding and tracing the progression, interaction and intrinsic variability of the magnetized activity bands that belong to the Sun's 22-year magnetic activity cycle. The intra- and extra-hemispheric interaction of these magnetic bands appear to explain the occurrence of decadal scale variability that primarily manifests itself in the sunspot cycle. However, on timescales of ten months or so, those bands posses their own internal variability with an amplitude of the same order of magnitude as the decadal scale. The latter have been tied to the existence of magnetized Rossby waves in the solar convection zone that result in surges of magnetic flux emergence that correspondingly modulate our star's radiative and particulate output. One of the most important events in the progression of these bands is their (apparent) termination at the solar equator that signals a global increase in magnetic flux emergence that becomes the new solar cycle. We look at the particulate and radiative implications of these termination points, their temporal recurrence and signature, from the Sun to the Earth, and show the correlated signature of solar cycle termination events and major oceanic oscillations that extend back many decades. A combined one-two punch of reduced particulate forcing and increased radiative forcing that result from the termination of one solar cycle and rapid blossoming of another correlates strongly with a shift from El Niño to La Niña conditions in the Pacific Ocean. This shift does not occur at solar minima, nor solar maxima, but at a particular, non-periodic, time in between. The failure to identify these termination points, and their relative irregularity, have inhibited a correlation to be observed and physical processes to be studied. This result potentially opens the door to a broader understanding of solar variability on our planet and its weather. Ongoing tracking of solar magnetic band migration indicates that Cycle 24 will terminate in the 2020 timeframe and thus we may expect to see an attendant shift to La Niña conditions at that time.

Using Motion Planning to Determine the Existence of an Accessible Route in a CAD Environment

ERIC Educational Resources Information Center

Pan, Xiaoshan; Han, Charles S.; Law, Kincho H.

2010-01-01

We describe an algorithm based on motion-planning techniques to determine the existence of an accessible route through a facility for a wheeled mobility device. The algorithm is based on LaValle's work on rapidly exploring random trees and is enhanced to take into consideration the particularities of the accessible route domain. Specifically, the…

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

Dolen, James; Harris, Philip; Marzani, Simone

Here, we explore the scale-dependence and correlations of jet substructure observables to improve upon existing techniques in the identification of highly Lorentz-boosted objects. Modified observables are designed to remove correlations from existing theoretically well-understood observables, providing practical advantages for experimental measurements and searches for new phenomena. We study such observables in W jet tagging and provide recommendations for observables based on considerations beyond signal and background efficiencies.

Effectiveness of Drafting Models for Engineering Technology Students and Impacts on Spatial Visualization Ability: An Analysis and Consideration of Critical Variables

ERIC Educational Resources Information Center

Katsioloudis, Petros J.; Stefaniak, Jill E.

2018-01-01

Results from a number of studies indicate that the use of drafting models can positively influence the spatial visualization ability for engineering technology students. However, additional variables such as light, temperature, motion and color can play an important role but research provides inconsistent results. Considering this, a set of 5…

Specific gravity of hybrid poplars in the north-central region, USA: within-tree variability and site × genotype effects

Treesearch

William L. Headlee; Ronald S. Jr. Zalesny; Richard B. Hall; Edmund O. Bauer; Bradford Bender; Bruce A. Birr; Raymond O. Miller; Jesse A. Randall; Adam H. Wiese

2013-01-01

Specific gravity is an important consideration for traditional uses of hybrid poplars for pulp and solid wood products, as well as for biofuels and bioenergy production. While specific gravity has been shown to be under strong genetic control and subject to within-tree variability, the role of genotype × environment interactions is poorly understood. Most...

Compact Representations of Extended Causal Models

DTIC Science & Technology

2012-10-01

get a yet more compact representation by assuming that, by default , it is typical for the variables to obey the structural equations. Finally, in...Halpern and Hitchcock (2011), is to incorporate considerations about about defaults , typicality, and normality. “Normality” and its cognates (“normal...atypical to violate it. 17 Variables typically obey the structural equations. Thus, it is often far more efficient to assume this holds by default

Low-resolution Australasian palaeoclimate records of the last 2000 years

NASA Astrophysics Data System (ADS)

Dixon, Bronwyn C.; Tyler, Jonathan J.; Lorrey, Andrew M.; Goodwin, Ian D.; Gergis, Joëlle; Drysdale, Russell N.

2017-10-01

Non-annually resolved palaeoclimate records in the Australasian region were compiled to facilitate investigations of decadal to centennial climate variability over the past 2000 years. A total of 675 lake and wetland, geomorphic, marine, and speleothem records were identified. The majority of records are located near population centres in southeast Australia, in New Zealand, and across the maritime continent, and there are few records from the arid regions of central and western Australia. Each record was assessed against a set of a priori criteria based on temporal resolution, record length, dating methods, and confidence in the proxy-climate relationship over the Common Era. A subset of 22 records met the criteria and were endorsed for subsequent analyses. Chronological uncertainty was the primary reason why records did not meet the selection criteria. New chronologies based on Bayesian techniques were constructed for the high-quality subset to ensure a consistent approach to age modelling and quantification of age uncertainties. The primary reasons for differences between published and reconstructed age-depth models were the consideration of the non-singular distribution of ages in calibrated 14C dates and the use of estimated autocorrelation between sampled depths as a constraint for changes in accumulation rate. Existing proxies and reconstruction techniques that successfully capture climate variability in the region show potential to address spatial gaps and expand the range of climate variables covering the last 2000 years in the Australasian region. Future palaeoclimate research and records in Australasia could be greatly improved through three main actions: (i) greater data availability through the public archiving of published records; (ii) thorough characterisation of proxy-climate relationships through site monitoring and climate sensitivity tests; and (iii) improvement of chronologies through core-top dating, inclusion of tephra layers where possible, and increased date density during the Common Era.

Examining the Gap: Compensation Disparities between Male and Female Physician Assistants.

PubMed

Smith, Noël; Cawley, James F; McCall, Timothy C

Compensation disparities between men and women have been problematic for decades, and there is considerable evidence that the gap cannot be entirely explained by nongender factors. The current study examined the compensation gap in the physician assistant (PA) profession. Compensation data from 2014 was collected by the American Academy of PAs in 2015. Practice variables, including experience, specialty, and hours worked, were controlled for in an ordinary least-squares sequential regression model to examine whether there remained a disparity in total compensation. In addition, the absolute disparity in compensation was compared with historical data collected by American Academy of PAs over the previous 1.5 decades. Without controlling for practice variables, a total compensation disparity of $16,052 existed between men and women in the PA profession. Even after PA practice variables were controlled for, a total compensation disparity of $9,695 remained between men and women (95% confidence interval, $8,438-$10,952). A 17-year trend indicates the absolute disparity between men and women has not lessened, although the disparity as a percent of male compensation has decreased in recent years. There remain challenges to ensuring pay equality in the PA profession. Even when compensation-relevant factors such as experience, hours worked, specialty, postgraduate training, region, and call are controlled for, there is still a substantial gender disparity in PA compensation. Remedies that may address this pay inequality include raising awareness of compensation disparities, teaching effective negotiation skills, assisting employers as they develop equitable compensation plans, having less reliance on past salary in position negotiation, and professional associations advocating for policies that support equal wages and opportunities, regardless of personal characteristics. Copyright © 2017 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

Hydrologic filtering of fish life history strategies across the United States: implications for stream flow alteration

DOE PAGES

McManamay, Ryan A.; Frimpong, Emmanuel A.

2015-01-01

Lotic fish have developed life history strategies adapted to the natural variation in stream flow regimes. The natural timing, duration, and magnitude of flow events has contributed to the diversity, production, and composition of fish assemblages over time. Studies evaluating the role of hydrology in structuring fish assemblages have been more common at the local or regional scale with very few studies conducted at the continental scale. Furthermore, quantitative linkages between natural hydrologic patterns and fish assemblages are rarely used to make predictions of ecological consequences of hydrologic alterations. We ask two questions: (1) what is the relative role ofmore » hydrology in structuring fish assemblages at large scales? and (2) can relationships between fish assemblages and natural hydrology be utilized to predict fish assemblage responses to hydrologic disturbance? We developed models to relate fish life histories and reproductive strategies to landscape and hydrologic variables separately and then combined. Models were then used to predict the ecological consequences of altered hydrology due to dam regulation. Although hydrology plays a considerable role in structuring fish assemblages, the performance of models using only hydrologic variables was lower than that of models constructed using landscape variables. Isolating the relative importance of hydrology in structuring fish assemblages at the continental scale is difficult since hydrology is interrelated to many landscape factors. By applying models to dam-regulated hydrologic data, we observed some consistent predicted responses in fish life history strategies and modes of reproduction. In agreement with existing literature, equilibrium strategists are predicted to increase following dam regulation, whereas opportunistic and periodic species are predicted to decrease. In addition, dam regulation favors the selection of reproductive strategies with extended spawning seasons and preference for stable conditions.« less

Effect of genetic background on the contribution of New Zealand Black loci to autoimmune lupus nephritis

PubMed Central

Rozzo, Stephen J.; Vyse, Timothy J.; Drake, Charles G.; Kotzin, Brian L.

1996-01-01

Autoimmune diseases such as systemic lupus erythematosus are complex genetic traits with contributions from major histocompatibility complex (MHC) genes and multiple unknown non-MHC genes. Studies of animal models of lupus have provided important insight into the immunopathogenesis of disease, and genetic analyses of these models overcome certain obstacles encountered when studying human patients. Genome-wide scans of different genetic crosses have been used to map several disease-linked loci in New Zealand hybrid mice. Although some consensus exists among studies mapping the New Zealand Black (NZB) and New Zealand White (NZW) loci that contribute to lupus-like disease, considerable variability is also apparent. A variable in these studies is the genetic background of the non-autoimmune strain, which could influence genetic contributions from the affected strain. A direct examination of this question was undertaken in the present study by mapping NZB nephritis-linked loci in backcrosses involving different non-autoimmune backgrounds. In a backcross with MHC-congenic C57BL/6J mice, H2z appeared to be the strongest genetic determinant of severe lupus nephritis, whereas in a backcross with congenic BALB/cJ mice, H2z showed no influence on disease expression. NZB loci on chromosomes 1, 4, 11, and 14 appeared to segregate with disease in the BALB/cJ cross, but only the influence of the chromosome 1 locus spanned both crosses and showed linkage with disease when all mice were considered. Thus, the results indicate that contributions from disease-susceptibility loci, including MHC, may vary markedly depending on the non-autoimmune strain used in a backcross analysis. These studies provide insight into variables that affect genetic heterogeneity and add an important dimension of complexity for linkage analyses of human autoimmune disease. PMID:8986781

Geomorphological assessment of sediment contamination in an urban stream system

USGS Publications Warehouse

Rhoads, B.L.; Cahill, R.A.

1999-01-01

Little is known about the influence of fluvial-geomorphological features on the dispersal of sediment-related contaminants in urban drainage systems. This study investigates the relation between reach-scale geomorphological conditions and network-scale patterns of trace-element concentrations in a partially urbanized stream system in East-Central Illinois, USA Robust statistical analysis of bulk sediment samples reveals levels of Cr, Cu, Pb, Ni, and Zn exceed contamination thresholds in the portion of the watershed in close proximity to potential sources of pollution-in this case storm-sewer outfalls. Although trace-element concentrations decrease rapidly downstream from these sources, substantial local variability in metal levels exists within contaminated reaches. This local variability is related to reach-scale variation in fluvial-geomorphic conditions, which in turn produces variation in the degree of sorting and organic-matter content of bed material. Metal concentrations at contaminated sites also exhibit considerable variability over time. Analytical tests on specific size fractions of material collected at a highly contaminated site indicate that Cr and Ni are concentrated in the 0.063 to 0.250 mm fraction of the sediment. This fraction also has elevated concentration of Zr. SEM analysis shows that the fine sand fraction contains shards of stainless steel within a matrix of zircon sand, an industrial material associated with a nearby alloy casting operation. Samples of suspended load and bedload at the contaminated site also have elevated amounts of trace metals, but concentrations of Ni and Cr in the bedload are less than concentrations in the bed material, suggesting that these trace elements are relatively immobile. Off the other hand, amounts of CU and Zn in the bedload exceed concentrations in the bed material, implying that these trace metals are preferentially mobilized during transport events.

Social cognition in patients with schizophrenia, their unaffected first degree relatives and healthy controls. Comparison between groups and analysis of associated clinical and sociodemographic variables.

PubMed

Rodríguez Sosa, Juana Teresa; Gil Santiago, Hiurma; Trujillo Cubas, Angel; Winter Navarro, Marta; León Pérez, Petra; Guerra Cazorla, Luz Marina; Martín Jiménez, José María

2013-01-01

To evaluate and compare the social cognition in patients with schizophrenia, healthy first-degree relatives and controls, by studying the relationship between social cognition and nonsocial cognition, psychopathology, and other clinical and sociodemographic variables. The total sample was comprised of patients diagnosed with paranoid schizophrenia (N = 29), healthy first-degree relatives (N = 21) and controls (N = 28). All groups were assessed with an ad hoc questionnaire and a Social Cognition Scale, which assessed the domains: emotional processing, social perception and attributional style in a Spanish population. The patient group was also assessed with the Scale for the Positive and Negative Syndrome Scale and the Mini-mental state examination. Statistical analyses were performed with SPSS version 15.0. Patients scored significantly worse in all domains of social cognition assessed, compared with controls, and mastery attributional style, compared with relatives. The type of psychopathology correlated negatively and statistically significantly with different domains of social cognition: negative symptoms with emotional processing and attributional style, and positive symptoms with social perception. Basic cognition scores correlated positively and statistically significantly with the domains social perception and attributional style. Social cognition has become an interesting object of study, especially in how it relates to non-social cognition, psychopathology and global functioning of patients, bringing new elements to be considered in the early detection, comprehensive treatment and psychosocial rehabilitation of patients. Its conceptualization as trait variable, the consideration of the existence of a continuum between patients and relatives are plausible hypotheses that require further research. Copyright © 2012 SEP y SEPB. Published by Elsevier Espana. All rights reserved.

Hydrologic filtering of fish life history strategies across the United States: implications for stream flow alteration

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

McManamay, Ryan A.; Frimpong, Emmanuel A.

Lotic fish have developed life history strategies adapted to the natural variation in stream flow regimes. The natural timing, duration, and magnitude of flow events has contributed to the diversity, production, and composition of fish assemblages over time. Studies evaluating the role of hydrology in structuring fish assemblages have been more common at the local or regional scale with very few studies conducted at the continental scale. Furthermore, quantitative linkages between natural hydrologic patterns and fish assemblages are rarely used to make predictions of ecological consequences of hydrologic alterations. We ask two questions: (1) what is the relative role ofmore » hydrology in structuring fish assemblages at large scales? and (2) can relationships between fish assemblages and natural hydrology be utilized to predict fish assemblage responses to hydrologic disturbance? We developed models to relate fish life histories and reproductive strategies to landscape and hydrologic variables separately and then combined. Models were then used to predict the ecological consequences of altered hydrology due to dam regulation. Although hydrology plays a considerable role in structuring fish assemblages, the performance of models using only hydrologic variables was lower than that of models constructed using landscape variables. Isolating the relative importance of hydrology in structuring fish assemblages at the continental scale is difficult since hydrology is interrelated to many landscape factors. By applying models to dam-regulated hydrologic data, we observed some consistent predicted responses in fish life history strategies and modes of reproduction. In agreement with existing literature, equilibrium strategists are predicted to increase following dam regulation, whereas opportunistic and periodic species are predicted to decrease. In addition, dam regulation favors the selection of reproductive strategies with extended spawning seasons and preference for stable conditions.« less

Variability in Non-Cardiac Surgical Procedures in Children with Congenital Heart Disease

PubMed Central

Sulkowski, Jason P.; Cooper, Jennifer N.; McConnell, Patrick I.; Pasquali, Sara K.; Shah, Samir S.; Minneci, Peter C.; Deans, Katherine J.

2014-01-01

Background The purpose of this study was to examine the volume and variability of non-cardiac surgeries performed in children with congenital heart disease (CHD) requiring cardiac surgery in the first year of life. Methods Patients who underwent cardiac surgery by 1 year of age and had a minimum 5-year follow-up at 22 of the hospitals contributing to the Pediatric Health Information System database between 2004–2012 were included. Frequencies of non-cardiac surgical procedures by age 5 years were determined and categorized by subspecialty. Patients were stratified according to their maximum RACHS-1 (Risk Adjustment in Congenital Heart Surgery) category. The proportions of patients across hospitals who had a non-cardiac surgical procedure for each subspecialty were compared using logistic mixed effects models. Results 8,857 patients underwent congenital heart surgery during the first year of life, 3,621 (41%) of whom had 13,894 non-cardiac surgical procedures by 5 years. Over half of all procedures were in general surgery (4,432; 31.9%) or otolaryngology (4,002; 28.8%). There was significant variation among hospitals in the proportion of CHD patients having non-cardiac surgical procedures. Compared to children in the low risk group (RACHS-1 categories 1–3), children in the high-risk group (categories 4–6) were more likely to have general, dental, orthopedic, and thoracic procedures. Conclusions Children with CHD requiring cardiac surgery frequently also undergo non-cardiac surgical procedures; however, considerable variability in the frequency of these procedures exists across hospitals. This suggests a lack of uniformity in indications used for surgical intervention. Further research should aim to better standardize care for this complex patient population. PMID:25475794

A methodology for risk analysis based on hybrid Bayesian networks: application to the regasification system of liquefied natural gas onboard a floating storage and regasification unit.

PubMed

Martins, Marcelo Ramos; Schleder, Adriana Miralles; Droguett, Enrique López

2014-12-01

This article presents an iterative six-step risk analysis methodology based on hybrid Bayesian networks (BNs). In typical risk analysis, systems are usually modeled as discrete and Boolean variables with constant failure rates via fault trees. Nevertheless, in many cases, it is not possible to perform an efficient analysis using only discrete and Boolean variables. The approach put forward by the proposed methodology makes use of BNs and incorporates recent developments that facilitate the use of continuous variables whose values may have any probability distributions. Thus, this approach makes the methodology particularly useful in cases where the available data for quantification of hazardous events probabilities are scarce or nonexistent, there is dependence among events, or when nonbinary events are involved. The methodology is applied to the risk analysis of a regasification system of liquefied natural gas (LNG) on board an FSRU (floating, storage, and regasification unit). LNG is becoming an important energy source option and the world's capacity to produce LNG is surging. Large reserves of natural gas exist worldwide, particularly in areas where the resources exceed the demand. Thus, this natural gas is liquefied for shipping and the storage and regasification process usually occurs at onshore plants. However, a new option for LNG storage and regasification has been proposed: the FSRU. As very few FSRUs have been put into operation, relevant failure data on FSRU systems are scarce. The results show the usefulness of the proposed methodology for cases where the risk analysis must be performed under considerable uncertainty. © 2014 Society for Risk Analysis.

A method for determining haploid and triploid genotypes and their association with vascular phenotypes in Williams syndrome and 7q11.23 duplication syndrome.

PubMed

Gregory, Michael D; Kolachana, Bhaskar; Yao, Yin; Nash, Tiffany; Dickinson, Dwight; Eisenberg, Daniel P; Mervis, Carolyn B; Berman, Karen F

2018-04-04

Williams syndrome ([WS], 7q11.23 hemideletion) and 7q11.23 duplication syndrome (Dup7) show contrasting syndromic symptoms. However, within each group there is considerable interindividual variability in the degree to which these phenotypes are expressed. Though software exists to identify areas of copy number variation (CNV) from commonly-available SNP-chip data, this software does not provide non-diploid genotypes in CNV regions. Here, we describe a method for identifying haploid and triploid genotypes in CNV regions, and then, as a proof-of-concept for applying this information to explain clinical variability, we test for genotype-phenotype associations. Blood samples for 25 individuals with WS and 13 individuals with Dup7 were genotyped with Illumina-HumanOmni5M SNP-chips. PennCNV and in-house code were used to make genotype calls for each SNP in the 7q11.23 locus. We tested for association between the presence of aortic arteriopathy and genotypes of the remaining (haploid in WS) or duplicated (triploid in Dup7) alleles. Haploid calls in the 7q11.23 region were made for 99.0% of SNPs in the WS group, and triploid calls for 98.8% of SNPs in those with Dup7. The G allele of SNP rs2528795 in the ELN gene was associated with aortic stenosis in WS participants (p < 0.0049) while the A allele of the same SNP was associated with aortic dilation in Dup7. Commonly available SNP-chip information can be used to make haploid and triploid calls in individuals with CNVs and then to relate variability in specific genes to variability in syndromic phenotypes, as demonstrated here using aortic arteriopathy. This work sets the stage for similar genotype-phenotype analyses in CNVs where phenotypes may be more complex and/or where there is less information about genetic mechanisms.

Marine Socio-Environmental Covariates: queryable global layers of environmental and anthropogenic variables for marine ecosystem studies.

PubMed

Yeager, Lauren A; Marchand, Philippe; Gill, David A; Baum, Julia K; McPherson, Jana M

2017-07-01

Biophysical conditions, including climate, environmental stress, and habitat availability, are key drivers of many ecological processes (e.g., community assembly and productivity) and associated ecosystem services (e.g., carbon sequestration and fishery production). Furthermore, anthropogenic impacts such as coastal development and fishing can have drastic effects on the structure and function of marine ecosystems. Scientists need to account for environmental variation and human impacts to accurately model, manage, and conserve marine ecosystems. Although there are many types of environmental data available from global remote sensing and open-source data products, some are inaccessible to potential end-users because they exist as global layers in high temporal and spatial resolutions which require considerable computational power to process. Additionally, coastal locations often suffer from missing data or data quality issues which limit the utility of some global marine products for coastal sites. Herein we present the Marine Socio-Environmental Covariates dataset for the global oceans, which consists of environmental and anthropogenic variables summarized in ecologically relevant ways. The dataset includes four sets of environmental variables related to biophysical conditions (net primary productivity models corrected for shallow-water reflectance, wave energy including sheltered-coastline corrections) and landscape context (coral reef and land cover within varying radii). We also present two sets of anthropogenic variables, human population density (within varying radii) and distance to large population center, which can serve as indicators of local human impacts. We have paired global, summarized layers available for download with an online data querying platform that allows users to extract data for specific point locations with finer control of summary statistics. In creating these global layers and online platform, we hope to make the data accessible to a wide array of end-users with the goal of advancing marine ecosystem studies. © 2017 by the Ecological Society of America.

Variability in Regularity: Mining Temporal Mobility Patterns in London, Singapore and Beijing Using Smart-Card Data

PubMed Central

Zhong, Chen; Batty, Michael; Manley, Ed; Wang, Jiaqiu; Wang, Zijia; Chen, Feng; Schmitt, Gerhard

2016-01-01

To discover regularities in human mobility is of fundamental importance to our understanding of urban dynamics, and essential to city and transport planning, urban management and policymaking. Previous research has revealed universal regularities at mainly aggregated spatio-temporal scales but when we zoom into finer scales, considerable heterogeneity and diversity is observed instead. The fundamental question we address in this paper is at what scales are the regularities we detect stable, explicable, and sustainable. This paper thus proposes a basic measure of variability to assess the stability of such regularities focusing mainly on changes over a range of temporal scales. We demonstrate this by comparing regularities in the urban mobility patterns in three world cities, namely London, Singapore and Beijing using one-week of smart-card data. The results show that variations in regularity scale as non-linear functions of the temporal resolution, which we measure over a scale from 1 minute to 24 hours thus reflecting the diurnal cycle of human mobility. A particularly dramatic increase in variability occurs up to the temporal scale of about 15 minutes in all three cities and this implies that limits exist when we look forward or backward with respect to making short-term predictions. The degree of regularity varies in fact from city to city with Beijing and Singapore showing higher regularity in comparison to London across all temporal scales. A detailed discussion is provided, which relates the analysis to various characteristics of the three cities. In summary, this work contributes to a deeper understanding of regularities in patterns of transit use from variations in volumes of travellers entering subway stations, it establishes a generic analytical framework for comparative studies using urban mobility data, and it provides key points for the management of variability by policy-makers intent on for making the travel experience more amenable. PMID:26872333

Variability in Regularity: Mining Temporal Mobility Patterns in London, Singapore and Beijing Using Smart-Card Data.

PubMed

Zhong, Chen; Batty, Michael; Manley, Ed; Wang, Jiaqiu; Wang, Zijia; Chen, Feng; Schmitt, Gerhard

2016-01-01

To discover regularities in human mobility is of fundamental importance to our understanding of urban dynamics, and essential to city and transport planning, urban management and policymaking. Previous research has revealed universal regularities at mainly aggregated spatio-temporal scales but when we zoom into finer scales, considerable heterogeneity and diversity is observed instead. The fundamental question we address in this paper is at what scales are the regularities we detect stable, explicable, and sustainable. This paper thus proposes a basic measure of variability to assess the stability of such regularities focusing mainly on changes over a range of temporal scales. We demonstrate this by comparing regularities in the urban mobility patterns in three world cities, namely London, Singapore and Beijing using one-week of smart-card data. The results show that variations in regularity scale as non-linear functions of the temporal resolution, which we measure over a scale from 1 minute to 24 hours thus reflecting the diurnal cycle of human mobility. A particularly dramatic increase in variability occurs up to the temporal scale of about 15 minutes in all three cities and this implies that limits exist when we look forward or backward with respect to making short-term predictions. The degree of regularity varies in fact from city to city with Beijing and Singapore showing higher regularity in comparison to London across all temporal scales. A detailed discussion is provided, which relates the analysis to various characteristics of the three cities. In summary, this work contributes to a deeper understanding of regularities in patterns of transit use from variations in volumes of travellers entering subway stations, it establishes a generic analytical framework for comparative studies using urban mobility data, and it provides key points for the management of variability by policy-makers intent on for making the travel experience more amenable.

40 CFR 230.3 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

.... The legislative history of the Act reflects that “radioactive materials” as included within the... available and capable of being done after taking into consideration cost, existing technology, and logistics...

A Physically Based Framework for Modelling the Organic Fractionation of Sea Spray Aerosol from Bubble Film Langmuir Equilibria

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

Burrows, Susannah M.; Ogunro, O.; Frossard, Amanda

2014-12-19

The presence of a large fraction of organic matter in primary sea spray aerosol (SSA) can strongly affect its cloud condensation nuclei activity and interactions with marine clouds. Global climate models require new parameterizations of the SSA composition in order to improve the representation of these processes. Existing proposals for such a parameterization use remotely-sensed chlorophyll-a concentrations as a proxy for the biogenic contribution to the aerosol. However, both observations and theoretical considerations suggest that existing relationships with chlorophyll-a, derived from observations at only a few locations, may not be representative for all ocean regions. We introduce a novel frameworkmore » for parameterizing the fractionation of marine organic matter into SSA based on a competitive Langmuir adsorption equilibrium at bubble surfaces. Marine organic matter is partitioned into classes with differing molecular weights, surface excesses, and Langmuir adsorption parameters. The classes include a lipid-like mixture associated with labile dissolved organic carbon (DOC), a polysaccharide-like mixture associated primarily with semi-labile DOC, a protein-like mixture with concentrations intermediate between lipids and polysaccharides, a processed mixture associated with recalcitrant surface DOC, and a deep abyssal humic-like mixture. Box model calculations have been performed for several cases of organic adsorption to illustrate the underlying concepts. We then apply the framework to output from a global marine biogeochemistry model, by partitioning total dissolved organic carbon into several classes of macromolecule. Each class is represented by model compounds with physical and chemical properties based on existing laboratory data. This allows us to globally map the predicted organic mass fraction of the nascent submicron sea spray aerosol. Predicted relationships between chlorophyll-\\textit{a} and organic fraction are similar to existing empirical parameterizations, but can vary between biologically productive and non-productive regions, and seasonally within a given region. Major uncertainties include the bubble film thickness at bursting and the variability of organic surfactant activity in the ocean, which is poorly constrained. In addition, marine colloids and cooperative adsorption of polysaccharides may make important contributions to the aerosol, but are not included here. This organic fractionation framework is an initial step towards a closer linking of ocean biogeochemistry and aerosol chemical composition in Earth system models. Future work should focus on improving constraints on model parameters through new laboratory experiments or through empirical fitting to observed relationships in the real ocean and atmosphere, as well as on atmospheric implications of the variable composition of organic matter in sea spray.« less

Assessing Mediational Models: Testing and Interval Estimation for Indirect Effects

ERIC Educational Resources Information Center

Biesanz, Jeremy C.; Falk, Carl F.; Savalei, Victoria

2010-01-01

Theoretical models specifying indirect or mediated effects are common in the social sciences. An indirect effect exists when an independent variable's influence on the dependent variable is mediated through an intervening variable. Classic approaches to assessing such mediational hypotheses (Baron & Kenny, 1986; Sobel, 1982) have in recent years…

A Bayesian Semiparametric Latent Variable Model for Mixed Responses

ERIC Educational Resources Information Center

Fahrmeir, Ludwig; Raach, Alexander

2007-01-01

In this paper we introduce a latent variable model (LVM) for mixed ordinal and continuous responses, where covariate effects on the continuous latent variables are modelled through a flexible semiparametric Gaussian regression model. We extend existing LVMs with the usual linear covariate effects by including nonparametric components for nonlinear…

Is Amateur Astronomers’ Astronomy Knowledge a Barrier to Successful Outreach?

NASA Astrophysics Data System (ADS)

Slater, Timothy F.; Slater, S. J.; Price, C. A.; CenterAstronomy, CAPER; Education Research, Physics

2012-01-01

Considerable effort in astronomy education research has focused on developing assessment tools in the form of multiple-choice conceptual diagnostics and content knowledge surveys. This has been critically important for establishing the initial knowledge state of students and measure impacts of innovative instructional interventions over a universe of topics. Unfortunately, few of the existing instruments were constructed upon a solid list of clearly articulated and widely agreed upon learning objectives that span an entire introductory survey course. Moving beyond the 10-year old Astronomy Diagnostics Test, scholars at the CAPER Center for Astronomy & Physics Education Research developed and validated criterion referenced assessment tool, which is tightly aligned to the consensus learning goals stated by the AAS Chair's Conference on ASTRO 101, the AAAS Project 2061 Benchmarks, and the NRC National Science Education Standards, called the Test Of Astronomy STandards (TOAST). This multiple-choice instrument has a high degree of reliability and validity and is being deployed in a number of formal and informal learning environments. A collaborative research endeavor between the CAPER Team and the American Association of Variable Star Observers measured the astronomy content knowledge amateur astronomers, relative to widely agreed upon learning targets. We uncovered that our sample of 300 amateurs have higher than expected scores on the TOAST, significantly higher than students leaving our top-tier ASTRO 101 survey courses. Given recent learning sciences research demonstrating the potential of highly specialized languages that exist within some communities and rapidly declining membership rolls of formal amateur organizations, these scores could be interpreted as a potential communication barrier existing for engaging novices who are potential future club members. These results suggest that organizations may need to strategically clarify the nature of educational experiences they provide than can serve transformative in order to nurture a more robust pipeline of members.

Economics and financing of vaccines for diarrheal diseases.

PubMed

Bartsch, Sarah M; Lee, Bruce Y

2014-01-01

The considerable burden of infectious disease-caused diarrhea around the world has motivated the continuing development of a number of vaccine candidates over the past several decades with some reaching the market. As with all major public health interventions, understanding the economics and financing of vaccines against diarrheal diseases is essential to their development and implementation. This review focuses on each of the major infectious pathogens that commonly cause diarrhea, the current understanding of their economic burden, the status of vaccine development, and existing economic evaluations of the vaccines. While the literature on the economics and financing of vaccines against diarrhea diseases is growing, there is considerable room for more inquiry. Substantial gaps exist for many pathogens, circumstances, and effects. Economics and financing studies are integral to vaccine development and implementation.

Economics and financing of vaccines for diarrheal diseases

PubMed Central

Bartsch, Sarah M; Lee, Bruce Y

2014-01-01

The considerable burden of infectious disease-caused diarrhea around the world has motivated the continuing development of a number of vaccine candidates over the past several decades with some reaching the market. As with all major public health interventions, understanding the economics and financing of vaccines against diarrheal diseases is essential to their development and implementation. This review focuses on each of the major infectious pathogens that commonly cause diarrhea, the current understanding of their economic burden, the status of vaccine development, and existing economic evaluations of the vaccines. While the literature on the economics and financing of vaccines against diarrhea diseases is growing, there is considerable room for more inquiry. Substantial gaps exist for many pathogens, circumstances, and effects. Economics and financing studies are integral to vaccine development and implementation. PMID:24755623

Health, human rights, and the conduct of clinical research within oppressed populations

PubMed Central

Mills, Edward J; Singh, Sonal

2007-01-01

Background Clinical trials evaluating interventions for infectious diseases require enrolling participants that are vulnerable to infection. As clinical trials are conducted in increasingly vulnerable populations, issues of protection of these populations become challenging. In settings where populations are forseeably oppressed, the conduct of research requires considerations that go beyond common ethical concerns and into issues of international human rights law. Discussion Using examples of HIV prevention trials in Thailand, hepatitis-E prevention trials in Nepal and malaria therapeutic trials in Burma (Myanmar), we address the inadequacies of current ethical guidelines when conducting research within oppressed populations. We review existing legislature in the United States and United Kingdom that may be used against foreign investigators if trial hardships exist. We conclude by making considerations for research conducted within oppressed populations. PMID:17996056

Media reaction to a SETI success.

PubMed

Shostak, G S

1997-01-01

Consideration of the reaction to a SETI detection by the media, and the effect this will have on the public, is more than mere sociological speculation. An accurate forecast of the media's interest can lead to actions that will help ensure that correct and comprehensible information reaches the public. This is most critical in the first few weeks following a discovery. While a widely accepted protocol for dealing with a detection exists in the "Declaration of Principles Following the Detection of Extraterrestrial Intelligence," it gives scant consideration to the fact that the actual situation will be chaotic and not subject to easy control. The 1996 story about the possible discovery of martian microfossils has provided a useful precedent for what will happen if astronomers uncover the existence of alien intelligence.

Ergonomics: The Forgotten Variable.

ERIC Educational Resources Information Center

Fitterman, L. Jeffrey

1998-01-01

Defines ergonomics and discusses design and environmental considerations. Suggests work-space requirements for: tables, chairs, monitor height, ambient noise and light, electricity, and environmental hazards. Includes sources for additional information related to ergonomic design. (AEF)

Regulations and Ethical Considerations for Astronomy Education Research III: A Suggested Code of Ethics

NASA Astrophysics Data System (ADS)

Brogt, Erik; Foster, Tom; Dokter, Erin; Buxner, Sanlyn; Antonellis, Jessie

We present an argument for, and suggested implementation of, a code of ethics for the astronomy education research community. This code of ethics is based on legal and ethical considerations set forth by U.S. federal regulations and the existing code of conduct of the American Educational Research Association. We also provide a fictitious research study as an example for working through the suggested code of ethics.

Lyapounov variable: Entropy and measurement in quantum mechanics

PubMed Central

Misra, B.; Prigogine, I.; Courbage, M.

1979-01-01

We discuss the question of the dynamical meaning of the second law of thermodynamics in the framework of quantum mechanics. Previous discussion of the problem in the framework of classical dynamics has shown that the second law can be given a dynamical meaning in terms of the existence of so-called Lyapounov variables—i.e., dynamical variables varying monotonically in time without becoming contradictory. It has been found that such variables can exist in an extended framework of classical dynamics, provided that the dynamical motion is suitably unstable. In this paper we begin to extend these results to quantum mechanics. It is found that no dynamical variable with the characteristic properties of nonequilibrium entropy can be defined in the standard formulation of quantum mechanics. However, if the Hamiltonian has certain well-defined spectral properties, such variables can be defined but only as a nonfactorizable superoperator. Necessary nonfactorizability of such entropy operators M has the consequence that they cannot preserve the class of pure states. Physically, this means that the distinguishability between pure states and corresponding mixtures must be lost in the case of a quantal system for which the algebra of observables can be extended to include a new dynamical variable representing nonequilibrium entropy. We discuss how this result leads to a solution of the quantum measurement problem. It is also found that the question of existence of entropy of superoperators M is closely linked to the problem of defining an operator of time in quantum mechanics. PMID:16578757

MicroRNA Expression in Formalin-fixed Paraffin-embedded Cancer Tissue: Identifying Reference MicroRNAs and Variability.

PubMed

Boisen, Mogens Karsbøl; Dehlendorff, Christian; Linnemann, Dorte; Schultz, Nicolai Aagaard; Jensen, Benny Vittrup; Høgdall, Estrid Vilma Solyom; Johansen, Julia Sidenius

2015-12-29

Archival formalin-fixed paraffin-embedded (FFPE) cancer tissue samples are a readily available resource for microRNA (miRNA) biomarker identification. No established standard for reference miRNAs in FFPE tissue exists. We sought to identify stable reference miRNAs for normalization of miRNA expression in FFPE tissue samples from patients with colorectal (CRC) and pancreatic (PC) cancer and to quantify the variability associated with sample age and fixation. High-throughput miRNA profiling results from 203 CRC and 256 PC FFPE samples as well as from 37 paired frozen/FFPE samples from nine other CRC tumors (methodological samples) were used. Candidate reference miRNAs were identified by their correlation with global mean expression. The stability of reference genes was analyzed according to published methods. The association between sample age and global mean miRNA expression was tested using linear regression. Variability was described using correlation coefficients and linear mixed effects models. Normalization effects were determined by changes in standard deviation and by hierarchical clustering. We created lists of 20 miRNAs with the best correlation to global mean expression in each cancer type. Nine of these miRNAs were present in both lists, and miR-103a-3p was the most stable reference miRNA for both CRC and PC FFPE tissue. The optimal number of reference miRNAs was 4 in CRC and 10 in PC. Sample age had a significant effect on global miRNA expression in PC (50% reduction over 20 years) but not in CRC. Formalin fixation for 2-6 days decreased miRNA expression 30-65%. Normalization using global mean expression reduced variability for technical and biological replicates while normalization using the expression of the identified reference miRNAs reduced variability only for biological replicates. Normalization only had a minor impact on clustering results. We identified suitable reference miRNAs for future miRNA expression experiments using CRC- and PC FFPE tissue samples. Formalin fixation decreased miRNA expression considerably, while the effect of increasing sample age was estimated to be negligible in a clinical setting.

Student Failures on First-Year Medical Basic Science Courses and the USMLE Step 1: A Retrospective Study over a 20-Year Period

ERIC Educational Resources Information Center

Burns, E. Robert; Garrett, Judy

2015-01-01

Correlates of achievement in the basic science years in medical school and on the Step 1 of the United States Medical Licensing Examination® (USMLE®), (Step 1) in relation to preadmission variables have been the subject of considerable study. Preadmissions variables such as the undergraduate grade point average (uGPA) and Medical College Admission…

Variable structure control of spacecraft reorientation maneuvers

NASA Technical Reports Server (NTRS)

Sira-Ramirez, H.; Dwyer, T. A. W., III

1986-01-01

A Variable Structure Control (VSC) approach is presented for multi-axial spacecraft reorientation maneuvers. A nonlinear sliding surface is proposed which results in an asymptotically stable, ideal linear sliding motion of Cayley-Rodriques attitude parameters. By imposing a desired equivalent dynamics on the attitude parameters, the approach is devoid of optimal control considerations. The single axis case provides a design scheme for the multiple axes design problem. Illustrative examples are presented.

Methodology for utilizing survey skid data.

DOT National Transportation Integrated Search

1975-01-01

This report sets forth procedures for utilizing survey skid data with consideration given to testing variabilities and relationships between the three testing devices used in Virginia namely, the Virginia Department of Highways & Transportation's tra...

Groundwater-fed irrigation impacts spatially distributed temporal scaling behavior of the natural system: a spatio-temporal framework for understanding water management impacts

NASA Astrophysics Data System (ADS)

Condon, Laura E.; Maxwell, Reed M.

2014-03-01

Regional scale water management analysis increasingly relies on integrated modeling tools. Much recent work has focused on groundwater-surface water interactions and feedbacks. However, to our knowledge, no study has explicitly considered impacts of management operations on the temporal dynamics of the natural system. Here, we simulate twenty years of hourly moisture dependent, groundwater-fed irrigation using a three-dimensional, fully integrated, hydrologic model (ParFlow-CLM). Results highlight interconnections between irrigation demand, groundwater oscillation frequency and latent heat flux variability not previously demonstrated. Additionally, the three-dimensional model used allows for novel consideration of spatial patterns in temporal dynamics. Latent heat flux and water table depth both display spatial organization in temporal scaling, an important finding given the spatial homogeneity and weak scaling observed in atmospheric forcings. Pumping and irrigation amplify high frequency (sub-annual) variability while attenuating low frequency (inter-annual) variability. Irrigation also intensifies scaling within irrigated areas, essentially increasing temporal memory in both the surface and the subsurface. These findings demonstrate management impacts that extend beyond traditional water balance considerations to the fundamental behavior of the system itself. This is an important step to better understanding groundwater’s role as a buffer for natural variability and the impact that water management has on this capacity.

Socio-demographic diversity and unexplained variation in death rates among the most deprived parliamentary constituencies in Britain.

PubMed

Tunstall, H; Mitchell, R; Gibbs, J; Platt, S; Dorling, D

2012-06-01

There is considerable unexplained variation in death rates between deprived areas of Britain. This analysis assesses the degree of variation in socio-demographic factors among deprivation deciles and how variables associated with deaths differ among the most deprived areas. Death rates 1996-2001, Carstairs' 2001 deprivation score and indicators, population density, black and minority ethnic group (BME) and population change 1971-2001 were calculated for 641 parliamentary constituencies in Britain. Constituencies were grouped into Carstairs' deciles. We assessed standard errors of all variables by decile and the relationship between death rates and socio-demographic variables with Pearson's correlations and linear regression by decile and for all constituencies combined. Standard errors in death rates and most socio-demographic variables were greatest for the most deprived decile. Death rates among all constituencies were positively correlated with Carstairs' score and indicators, density and BME, but for the most deprived decile, there was no association with Carstairs and a negative correlation with overcrowding, density and BME. For the most deprived decile multivariate models containing population density, BME and change had substantially higher R(2). Understanding variations in death rates between deprived areas requires greater consideration of their socio-demographic diversity including their population density, ethnicity and migration.

An eco-hydrologic model of malaria outbreaks

NASA Astrophysics Data System (ADS)

Montosi, E.; Manzoni, S.; Porporato, A.; Montanari, A.

2012-03-01

Malaria is a geographically widespread infectious disease that is well known to be affected by climate variability at both seasonal and interannual timescales. In an effort to identify climatic factors that impact malaria dynamics, there has been considerable research focused on the development of appropriate disease models for malaria transmission and their consideration alongside climatic datasets. These analyses have focused largely on variation in temperature and rainfall as direct climatic drivers of malaria dynamics. Here, we further these efforts by considering additionally the role that soil water content may play in driving malaria incidence. Specifically, we hypothesize that hydro-climatic variability should be an important factor in controlling the availability of mosquito habitats, thereby governing mosquito growth rates. To test this hypothesis, we reduce a nonlinear eco-hydrologic model to a simple linear model through a series of consecutive assumptions and apply this model to malaria incidence data from three South African provinces. Despite the assumptions made in the reduction of the model, we show that soil water content can account for a significant portion of malaria's case variability beyond its seasonal patterns, whereas neither temperature nor rainfall alone can do so. Future work should therefore consider soil water content as a simple and computable variable for incorporation into climate-driven disease models of malaria and other vector-borne infectious diseases.