2,038 research outputs found
Quantum reservoirs with ion chains
Ion chains are promising platforms for studying and simulating quantum
reservoirs. One interesting feature is that their vibrational modes can mediate
entanglement between two objects which are coupled through the vibrational
modes of the chain. In this work we analyse entanglement between the transverse
vibrations of two heavy impurity defects embedded in an ion chain, which is
generated by the coupling with the chain vibrations. We verify general scaling
properties of the defects dynamics and demonstrate that entanglement between
the defects can be a stationary feature of these dynamics. We then analyse
entanglement in chains composed of tens of ions and propose a measurement
scheme which allows one to verify the existence of the predicted entangled
state.Comment: 14 pages, 12 figure
X-ray production in low energy proton stopping
The X-ray yields of stopping protons in an iron-nickel-cobalt alloy are calculated for use in predicting radiation damage in encased electronic devices
A Geospatial Analysis of CDC-funded HIV Prevention Programs for African Americans in the United States
Given the increase in HIV/AIDS infection rates among racial and ethnic minorities, particularly African Americans, this study was undertaken as part of a larger research effort to examine the distribution of HIV prevention services focusing on African American populations within the United States. Data were gathered via a national survey of community-based organizations (CBOs) funded by the Centers for Disease Control and Prevention (CDC). A geocoded national database was constructed to identify, locate, and map these HIV prevention programs. A total of 1,020 CBOs responded to the survey, yielding a response rate of 70.3%. These CBOs administered a total of 3,028 HIV prevention programs. Data describing intervention types and persons served, combined with the address and service area of responding CBOs, were integrated with census data (2000) and analyzed by using a geographic information system (GIS). The results of our national level analysis show that HIV prevention services for African Americans have fair coverage where African Americans comprise a substantial proportion of the population in urban areas in northeastern states, but that HIV prevention services for African Americans are inadequately distributed in the southeastern states. A local-level analysis was conducted for Alabama, where 68% of HIV/AIDS cases are among African Americans. Specific interventions such as street and community outreach, health communications, and public information are fairly well provided to African Americans in more urban cities in Alabama, however, individual- and group-level interventions have poor coverage in rural areas where a large percentage of African-Americans live. Overall, our study illustrates that the use of GIS adds value when used with other data sources to provide prevention services that are accessible to the populations most in need
Entangling two defects via a surrounding crystal
We theoretically show how two impurity defects in a crystalline structure can
be entangled through coupling with the crystal. We demonstrate this with a
harmonic chain of trapped ions in which two ions of a different species are
embedded. Entanglement is found for sufficiently cold chains and for a certain
class of initial, separable states of the defects. It results from the
interplay between localized modes which involve the defects and the interposed
ions, it is independent of the chain size, and decays slowly with the distance
between the impurities. These dynamics can be observed in systems exhibiting
spatial order, viable realizations are optical lattices, optomechanical
systems, or cavity arrays in circuit QED.Comment: 5 pages, 5 figure
Hyperbaric Oxygen Therapy in in Neurodegenerative Disease with Case Presentations of Alzheimer\u27s Disease
Dr. Harch’s keynote will outline his case presentations on Alzheimer’s, supported by Dr. Fogarty. To better understand that neurodegenerative diseases result from a combination of genetic factors and cumulative environmental factors that generate central nervous system inflammation and wounding. To understand the positive and negative literature on HBOT in a variety of neurodegenerative and neurodevelopment diseases and the effects of HBOT on inflammation
Hyperbaric oxygen therapy for Alzheimer’s dementia with positron emission tomography imaging: a case report
A 58-year-old female was diagnosed with Alzheimer’s dementia (AD) which was rapidly progressive in the 8 months prior to initiation of hyperbaric oxygen therapy (HBOT). 18Fluorodeoxyglucose (18FDG) positron emission tomography (PET) brain imaging demonstrated global and typical metabolic deficits in AD (posterior temporal-parietal watershed and cingulate areas). An 8-week course of HBOT reversed the patient’s symptomatic decline. Repeat PET imaging demonstrated a corresponding 6.5–38% regional and global increase in brain metabolism, including increased metabolism in the typical AD diagnostic areas of the brain. Continued HBOT in conjunction with standard pharmacotherapy maintained the patient’s symptomatic level of function over an ensuing 22 months. This is the first reported case of simultaneous HBOT-induced symptomatic and 18FDG PET documented improvement of brain metabolism in AD and suggests an effect on global pathology in AD
Within-group norming: Just because it might be legal, doesn't mean we should do it
Within-group norming has been suggested as a potential solution to the problem of the adverse impact of cognitive predictors of job performance. Although it is a method that has been tried and rejected overseas, there may be a place for it in the Australian context. However, other options should not be ignored. This paper presents some caveats regarding within-group norming and offers some alternative strategies
Pharmacoepidemiology for nephrologists: do proton pump inhibitors cause chronic kidney disease?
Pharmacoepidemiology studies are increasingly used for research into safe prescribing in chronic kidney disease (CKD). Typically, patients prescribed a drug are compared with patients who are not on the drug and outcomes are compared to draw conclusions about the drug effects. This review article aims to provide the reader with a framework to critically appraise such research. A key concern in pharmacoepidemiology studies is confounding, in that patients who have worse health status are prescribed more drugs or different agents and their worse outcomes are attributed to the drugs not the health status. It may be challenging to adjust for this using statistical methods unless a comparison group with a similar health status but who are prescribed a different (comparison) drug(s) is identified. Another challenge in pharmacoepidemiology is outcome misclassification, as people who are more ill engage more often with the health service, leading to earlier diagnosis in people who are frequent attenders. Finally, using replication cohorts with the same methodology in the same type of health system does not ensure that findings are more robust. We use two recent papers that investigated the association of proton pump inhibitor drugs with CKD as a device to review the main pitfalls of pharmacoepidemiology studies and how to attempt to mitigate against potential biases that can occur
Topological properties of punctual Hilbert schemes of almost-complex fourfolds (I)
In this article, we study topological properties of Voisin's punctual Hilbert
schemes of an almost-complex fourfold . In this setting, we compute their
Betti numbers and construct Nakajima operators. We also define tautological
bundles associated with any complex bundle on , which are shown to be
canonical in -theory
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