7,197 research outputs found
Device prepares aluminum surfaces for welding
Dry machining technique removes original surfaces to obtain contamination free welding surface. Device straddles edge being prepared and aligns with existing edges and adjacent surfaces of workpiece while sensing device regulates cut depth. Description of prototype is given
Modular Hamiltonians for Deformed Half-Spaces and the Averaged Null Energy Condition
We study modular Hamiltonians corresponding to the vacuum state for deformed
half-spaces in relativistic quantum field theories on . We
show that in addition to the usual boost generator, there is a contribution to
the modular Hamiltonian at first order in the shape deformation, proportional
to the integral of the null components of the stress tensor along the Rindler
horizon. We use this fact along with monotonicity of relative entropy to prove
the averaged null energy condition in Minkowski space-time. This subsequently
gives a new proof of the Hofman-Maldacena bounds on the parameters appearing in
CFT three-point functions. Our main technical advance involves adapting newly
developed perturbative methods for calculating entanglement entropy to the
problem at hand. These methods were recently used to prove certain results on
the shape dependence of entanglement in CFTs and here we generalize these
results to excited states and real time dynamics. We also discuss the AdS/CFT
counterpart of this result, making connection with the recently proposed
gravitational dual for modular Hamiltonians in holographic theories.Comment: 40 pages, 5 figure
The anatomy and the histology of bud- formation in the serpulid Filograna implexa and with some cytological observations on the nuclei of the neoblasts
External Features •
1. General, 11 •
2. Phases of life history . 22 •
3. Configuration of buds . . 24 •
4. Grouping of segments considered numerically . . 36Description of two abnormal buds , 55Alimentary canal , . 58Body wall •
1. Epithelium , . . . 63 •
2. Musculature ,
. . . . . . 70 •
3. Central nervous system . . . . . 85Blood system . . . . . . 05Coelomic cavities . . . . 114Glandular sac and excretion. . . . 116Histology of bud -formation, together with cytological
observations on the nuclei of the embryonic cells. 123.Summary. 152
Narrative, identity, and recovery from serious mental illness: A life history of a runner
In recent years, researchers have investigated the psychological effects of exercise for people with mental health problems, often by focusing on how exercise may alleviate symptoms of mental illness. In this article I take a different tack to explore the ways in which exercise contributed a sense of meaning, purpose, and identity to the life of one individual named Ben, a runner diagnosed with schizophrenia. Drawing on life history data, I conducted an analysis of narrative to explore the narrative types that underlie Ben's stories of mental illness and exercise. For Ben, serious mental illness profoundly disrupted a pre-existing athletic identity removing agency, continuity, and coherence from his life story. By returning to exercise several years later, Ben reclaimed his athletic identity and reinstated some degree of narrative agency, continuity, and coherence. While the relationships between narrative, identity, and mental health are undoubtedly complex, Ben's story suggests that exercise can contribute to recovery by being a personally meaningful activity which reinforces identity and sense of self
Relative biological effectiveness of fast neutrons compared with X-rays: Prenatal mortality in the mouse
The effects of fission neutrons and of X-rays on the mouse zygote are discussed. Seven-week-old virgin mice were allowed a 12-hour mating opportunity beginning at 7:00 P.M. Between 1:30 and 4:00 P.M., except where indicated otherwise, the females which had mated (vaginal plug) during the night were either irradiated or sham-irradiated. At the time of irradiation the zygotes were in a pronuclear stage. Sixteen days later the mice were killed and the uteri dissected. The number of dead embryos, live embryos, and gross anomalies were determined. Dead embryos were classified as to stage of development
Functional Connectivity of the Raphe Nuclei: Link to Tobacco Withdrawal in Smokers.
BackgroundAlthough nicotine alters serotonergic neurochemistry, clinical trials of serotonergic medications for smoking cessation have provided mixed results. Understanding the role of serotonergic dysfunction in tobacco use disorder may advance development of novel pharmacotherapies.MethodsFunctional magnetic resonance imaging was used to measure resting-state functional connectivity of the raphe nuclei as an indicator of serotonergic function. Connectivity of the dorsal and median raphe nuclei was compared between 18 young smokers (briefly abstinent, ~40 minutes post-smoking) and 19 young nonsmokers (16-21 years old); connectivity was also examined in a separate sample of overnight-abstinent smokers (18-25 years old), before and after smoking the first cigarette of the day. Relationships between connectivity of the raphe nuclei with psychological withdrawal and craving were tested in smokers.ResultsConnectivity of the median raphe nucleus with the right hippocampal complex was weaker in smokers than in nonsmokers and was negatively correlated with psychological withdrawal in smokers. In overnight-abstinent smokers, smoking increased connectivity of the median raphe nucleus with the right hippocampal complex, and the increase was positively correlated with the decrease in psychological withdrawal.ConclusionsRelief of withdrawal due to smoking is potentially linked to the serotonergic pathway that includes the median raphe nucleus and hippocampal complex. These results suggest that serotonergic medications may be especially beneficial for smokers who endorse strong psychological withdrawal during abstinence from smoking
Expenditure-based segmentation and visitor profiling at The Quays in Salford, UK
There is a substantial body of literature relating to tourism’s
economic impact at the macro level, but less is known about tourist
expenditure at a micro scale. This paper reports findings from a
survey of day-visitor expenditure by category at The Quays in Salford,
UK. Expenditure is influenced strongly by the visitor’s age,
frequency of visitation and visit motivation. Heavy, medium and
light expenditure segments and associated profiles are identified.
‘Heavy spenders’ are more likely to be female, in a family group and
have shopping as the main motivation for the visit. The implications
of the findings are discussed
Method for improved prediction of bone fracture risk using bone mineral density in structural analysis
A non-invasive in-vivo method of analyzing a bone for fracture risk includes obtaining data from the bone such as by computed tomography or projection imaging which data represents a measure of bone material characteristics such as bone mineral density. The distribution of the bone material characteristics is used to generate a finite element method (FEM) mesh from which load capability of the bone can be determined. In determining load capability, the bone is mathematically compressed, and stress, strain force, force/area versus bone material characteristics are determined
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