3,416 research outputs found
The simulation of action disorganisation in complex activities of daily living
No full textAction selection in everyday goal-directed tasks of moderate complexity is known to be subject to breakdown following extensive frontal brain injury. A model of action selection in such tasks is presented and used to explore three hypotheses concerning the origins of action disorganisation: that it is a consequence of reduced top-down excitation within a hierarchical action schema network coupled with increased bottom-up triggering of schemas from environmental sources, that it is a more general disturbance of schema activation modelled by excessive noise in the schema network, and that it results from a general disturbance of the triggering of schemas by object representations. Results suggest that the action disorganisation syndrome is best accounted for by a general disturbance to schema activation, while altering the balance between top-down and bottom-up activation provides an account of a related disorder - utilisation behaviour. It is further suggested that ideational apraxia (which may result from lesions to left temporoparietal areas and which has similar behavioural consequences to action disorganisation syndrome on tasks of moderate complexity) is a consequence of a generalised disturbance of the triggering of schemas by object representations. Several predictions regarding differences between action disorganisation syndrome and ideational apraxia that follow from this interpretation are detailed
SUPPLY CHAIN MANAGEMENT: IMPROVING VERTICAL COORDINATION IN FRUIT INDUSTRIES
No full textAgribusiness,
Holocene Relative Sea-Level Changes from Near-, Intermediate-, and Far-Field Locations
No full textHolocene relative sea-level (RSL) records exhibit spatial and temporal variability that arises mainly from the interaction of eustatic (land ice volume and thermal expansion) and isostatic (glacio- and hydro-) factors. We fit RSL histories from near-, intermediate-, and far-field locations with noisy-input Gaussian process models to assess rates of RSL change. Records from near-field regions (e.g., Antarctica, Greenland, Canada, Sweden, and Scotland) reveal a complex pattern of RSL fall from a maximum marine limit due to the net effect of eustatic sea-level rise and glacio-isostatic uplift with rates of RSL fall as great as -69 ± 9 m/ka. Intermediate-field regions (e.g., mid-Atlantic and Pacific coasts of the United States, Netherlands, Southern France, St. Croix) display variable rates of RSL rise from the cumulative effect of isostatic and eustatic factors. Fast rates of RSL rise (up to 10 ± 1 m/ka) are found in the early Holocene in regions near the center of forebulge collapse. Far-field RSL records exhibit a mid-Holocene highstand, the timing (between 8 and 4 ka) and magnitude (between <1 and 6 m) of which varies among South America, Africa, Asia and Oceania regions.Peer reviewe
Global and regional burden of cancer in 2016 arising from occupational exposure to selected carcinogens: a systematic analysis for the Global Burden of Disease Study 2016
No full textObjectives: this study provides a detailed analysis of the global and regional burden of cancer due to occupational carcinogens from the Global Burden of Disease 2016 study.Methods: the burden of cancer due to 14 International Agency for Research on Cancer Group 1 occupational carcinogens was estimated using the population attributable fraction, based on past population exposure prevalence and relative risks from the literature. The results were used to calculate attributable deaths and disability-adjusted life years (DALYs).Results: there were an estimated 349 000 (95% Uncertainty Interval 269 000 to 427 000) deaths and 7.2 (5.8 to 8.6) million DALYs in 2016 due to exposure to the included occupational carcinogens-3.9% (3.2% to 4.6%) of all cancer deaths and 3.4% (2.7% to 4.0%) of all cancer DALYs; 79% of deaths were of males and 88% were of people aged 55 -79 years. Lung cancer accounted for 86% of the deaths, mesothelioma for 7.9% and laryngeal cancer for 2.1%. Asbestos was responsible for the largest number of deaths due to occupational carcinogens (63%); other important risk factors were secondhand smoke (14%), silica (14%) and diesel engine exhaust (5%). The highest mortality rates were in high-income regions, largely due to asbestos-related cancers, whereas in other regions cancer deaths from secondhand smoke, silica and diesel engine exhaust were more prominent. From 1990 to 2016, there was a decrease in the rate for deaths (-10%) and DALYs (-15%) due to exposure to occupational carcinogens.Conclusions: work-related carcinogens are responsible for considerable disease burden worldwide. The results provide guidance for prevention and control initiatives.</p
Tools for evolutionary acquisition : a study of Multi-Attribute Tradespace Exploration (MATE) applied to the Space Based Radar (SBR)
No full textThesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2003.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Statement of responsibility on t.p. reads: 2nd Lieutenant Timothy J. Spaulding, USAF.Includes bibliographical references (p. 139-142).by Timothy J. Spaulding.S.M
Increasing Distributed Generation Penetration using Soft Normally-Open Points
No full textThis paper considers the effects of various voltage control solutions on facilitating an increase in allowable levels of distributed generation installation before voltage violations occur. In particular, the voltage control solution that is focused on is the implementation of `soft' normally-open points (SNOPs), a term which refers to power electronic devices installed in place of a normally-open point in a medium-voltage distribution network which allows for control of real and reactive power flows between each end point of its installation sites. While other benefits of SNOP installation are discussed, the intent of this paper is to determine whether SNOPs are a viable alternative to other voltage control strategies for this particular application. As such, the SNOPs ability to affect the voltage profile along feeders within a distribution system is focused on with other voltage control options used for comparative purposes. Results from studies on multiple network models with varying topologies are presented and a case study which considers economic benefits of increasing feasible DG penetration is also given
Hundreds of variants clustered in genomic loci and biological pathways affect human height
No full textMost common human traits and diseases have a polygenic pattern of inheritance: DNA sequence variants at many genetic loci influence the phenotype. Genome-wide association (GWA) studies have identified more than 600 variants associated with human traits(1), but these typically explain small fractions of phenotypic variation, raising questions about the use of further studies. Here, using 183,727 individuals, we show that hundreds of genetic variants, in at least 180 loci, influence adult height, a highly heritable and classic polygenic trait(2,3). The large number of loci reveals patterns with important implications for genetic studies of common human diseases and traits. First, the 180 loci are not random, but instead are enriched for genes that are connected in biological pathways (P = 0.016) and that underlie skeletal growth defects (P<0.001). Second, the likely causal gene is often located near the most strongly associated variant: in 13 of 21 loci containing a known skeletal growth gene, that gene was closest to the associated variant. Third, at least 19 loci have multiple independently associated variants, suggesting that allelic heterogeneity is a frequent feature of polygenic traits, that comprehensive explorations of already-discovered loci should discover additional variants and that an appreciable fraction of associated loci may have been identified. Fourth, associated variants are enriched for likely functional effects on genes, being over-represented among variants that alter amino-acid structure of proteins and expression levels of nearby genes. Our data explain approximately 10% of the phenotypic variation in height, and we estimate that unidentified common variants of similar effect sizes would increase this figure to approximately 16% of phenotypic variation (approximately 20% of heritable variation). Although additional approaches are needed to dissect the genetic architecture of polygenic human traits fully, our findings indicate that GWA studies can identify large numbers of loci that implicate biologically relevant genes and pathways
Evaluating Research Impact through Open Access to Scholarly Communication
No full textScientific research is a competitive business – in order to secure funding, promotion and tenure researchers must demonstrate their work has impact in their field. To maximise impact researchers undertake high priority research, aim to get results first, and publish in the highest impact journals. The Internet now presents a new opportunity to the scholarly author seeking higher impact: s/he can now make their work instantly accessible on the Web through author self-archiving. This growing body of open access literature (coupled with new publishing models that make journals available for-free to the reader) maximises research impact by maximising the number of people who can read it, and making it available sooner. Open access also provides a new opportunity for bibliometric research. This thesis describes the relatively recent phenomenon of open access to research literature, tools that were built to collect and analyse that literature, and the results of analyses of the effect of open access and its effect on author behaviour. It shows that articles self-archived by authors receive between 50-250% more citations, that rapid pre-printing on the Web has dramatically reduced the peak citation rate from over a year to virtually instant and how citation-impact – now widely used for evaluation – can be expanded to include a new web metric of download impact
A simulation-based concurrent engineering approach for assembly system design
No full textThesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering; in conjunction with the Leaders for Manufacturing Program at MIT, 2002.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (p. 81-82).by Timothy J. Sweitzer.S.M.M.B.A
Equipping Lay Leaders in Expository Preaching at Four Points Baptist Church in Centreville, Alabama
No full textThis project was designed to equip elder-qualified men in expository preaching at Four Points Baptist Church in Centreville, Alabama. Chapter 1 provides the context, rationale, purpose, goals, and research methodology of this project. Chapter 2 provides the biblical and theological basis for the project. Ezra 7:6–10 is used to describe the disposition a preacher needs prior to delivering a sermon. Passages from 2 Timothy demonstrate that Paul trained elder-qualified men to preach and expected Timothy to do the same. Chapter 3 provides the historical basis of the project by examining the lives and preaching ministries of John Calvin and Charles Spurgeon. Chapter 4 explains the preparation and implementation of the project, as well as provides a summary of the sessions that were taught. Chapter 5 is an evaluation of the project, highlighting its strengths and weaknesses. The statistics presented in Chapter 5 demonstrated that there were moderate improvements in participants’ perceptions but no improvements met the standard of statistical significance. In both pre-session and post-session surveys, participants were asked to state whether they could interpret the Bible accurately. The post-session survey revealed that all the men agreed or strongly agreed they could interpret the Bible accurately, which was an improvement of 16%. However, when analyzing the data of the pre-session survey and post-session survey through the t-test the results showed there was no significant statistical change between the pre-session survey and post-session survey scores: t(4)= -0.57, p= 0.60. Chapter 5 concludes with personal and theological reflections, along with future changes
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