403 research outputs found
The Buffalo Central Terminal and Economic Development
BCT was completed in 1929 by New York Central Railroad, shortly before the stock market crash leading to the Great Depression. Between 1929 and 1933 the railroads’ gross operating and net revenues fell; costs dramatically increased while passenger’s disposable incomes decreased. The railroads were responsible for their own maintenance and capital improvements, while the Federal Government was actively subsidizing auto, bus and air travel. In addition, taxes paid by the railroads to federal, state and municipal governments were being used to pay for their competitors’ infrastructure. The U.S.’s entry into World War II brought an increase in freight and passenger rail traffic because rails were an effective way to move war goods and there were gasoline rations as well as rubber and metal shortages. While the railroads were now increasing income like never before, they were stretched near to capacity in addition to the fact that resources were not available to maintain the trains (materials were being used to manufacture war goods). Once the war ended, the railroads’ freight and passenger traffic once again declined
Catholic Church Closings
The Catholic Diocese of Buffalo was established on April 23, 1847. It serves the following counties in New York State: Erie, Niagara, Genesee, Orleans, Chautauqua, Wyoming, Cattaraugus and Allegany. The Diocese covers 6,455 square miles and has a Catholic population of 702,884. In June 2005, Bishop Edward U. Kmiec, the bishop of Buffalo, initiated a “parish-based strategic plan and spiritual revitalization initiative” called “Journey in Faith and Grace.” Through this initiative, the Diocese of Buffalo “restructured” churches in the Vicariates of Southeast Buffalo, Northern Erie, and Eastern Erie. The restructuring called for 77 worship sites to be phased out, while 198 worship sites will remain in use
Cavity QED of Strongly Correlated Electron Systems: A No-go Theorem for Photon Condensation
In spite of decades of work it has remained unclear whether or not
superradiant quantum phases, referred to here as photon condensates, can occur
in equilibrium. In this Letter, we first show that when a non-relativistic
quantum many-body system is coupled to a cavity field, gauge invariance forbids
photon condensation. We then present a microscopic theory of the cavity quantum
electrodynamics of an extended Falicov-Kimball model, showing that, in
agreement with the general theorem, its insulating ferroelectric and exciton
condensate phases are not altered by the cavity and do not support photon
condensation.Comment: Reference list updated and minor typos correcte
Many-body localized quantum batteries
The collective and quantum behavior of many-body systems may be harnessed to achieve fast charging of energy storage devices, which have been recently dubbed quantum batteries. In this paper, we present an extensive numerical analysis of energy flow in a quantum battery described by a disordered quantum Ising chain Hamiltonian, whose equilibrium phase diagram presents many-body localized (MBL), Anderson localized (AL), and ergodic phases. We demonstrate that (i) the low amount of entanglement of the MBL phase guarantees much better work extraction capabilities, measured by the ergotropy, than the ergodic phase and (ii) interactions suppress temporal energy fluctuations in comparison with those of the noninteracting AL phase. Finally, we show that the statistical distribution of values of the optimal charging time is a clear-cut diagnostic tool of the MBL phase
Ultra-stable charging of fast-scrambling SYK quantum batteries
Collective behavior strongly influences the charging dynamics of quantum batteries (QBs). Here, we study the impact of nonlocal correlations on the energy stored in a system of N QBs. A unitary charging protocol based on a Sachdev-Ye-Kitaev (SYK) quench Hamiltonian is thus introduced and analyzed. SYK models describe strongly interacting systems with nonlocal correlations and fast thermalization properties. Here, we demonstrate that, once charged, the average energy stored in the QB is very stable, realizing an ultraprecise charging protocol. By studying fluctuations of the average energy stored, we show that temporal fluctuations are strongly suppressed by the presence of nonlocal correlations at all time scales. A comparison with other paradigmatic examples of many-body QBs shows that this is linked to the collective dynamics of the SYK model and its high level of entanglement. We argue that such feature relies on the fast scrambling property of the SYK Hamiltonian, and on its fast thermalization properties, promoting this as an ideal model for the ultimate temporal stability of a generic QB. Finally, we show that the temporal evolution of the ergotropy, a quantity that characterizes the amount of extractable work from a QB, can be a useful probe to infer the thermalization properties of a many-body quantum system
Persistent post-traumatic headache and migraine: Pre-clinical comparisons
Background: Oftentimes, persistent post traumatic headache (PPTH) and migraine are phenotypically similar and the only clinical feature that differentiate them is the presence of a mild or moderate traumatic brain injury (mTBI). The aim of this study is to describe the differences in brain area and in biochemical cascade after concussion and to define the efficacy and safety of treatments in use. Methods: Sources were chosen in according to the International Classification of Headache Disorder (ICHD) criteria. Results: The articles demonstrated a significant difference between PPTH and migraine regarding static functional connectivity (sFC) and dynamic functional connectivity (dFC) in brain structure that could be used for exploring the pathophysiological mechanisms in PPTH. Many studies described a cascade of neurometabolic changes that occur after traumatic brain injury. These variations are associated to the mechanism occurring when developing a PPTH. Conclusions: The state of art of this important topic show how although the mechanisms underlying the development of the two different diseases are different, the treatment of common migraine is efficacious in patients that have developed a post traumatic form
Theory of Photon Condensation in a Spatially-Varying Electromagnetic Field
The realization of equilibrium superradiant quantum phases (photon
condensates) in a spatially-uniform quantum cavity field is forbidden by a
"no-go" theorem stemming from gauge invariance. We here show that the no-go
theorem does not apply to spatially-varying quantum cavity fields. We find a
criterion for its occurrence that depends solely on the static, non-local
orbital magnetic susceptibility , of the electronic system
(ES) evaluated at a cavity photon momentum . Only 3DESs satisfying the
Condon inequality can harbor photon condensation.
For the experimentally relevant case of two-dimensional (2D) ESs embedded in
quasi-2D cavities the criterion again involves but also the
vertical size of the cavity. We use these considerations to identify electronic
properties that are ideal for photon condensation. Our theory is
non-perturbative in the strength of electron-electron interaction and therefore
applicable to strongly correlated ESs.Comment: 25 page
Entity Recommendation for Everyday Digital Tasks
Recommender systems can support everyday digital tasks by retrieving and recommending useful information contextually. This is becoming increasingly relevant in services and operating systems. Previous research often focuses on specific recommendation tasks with data captured from interactions with an individual application. The quality of recommendations is also often evaluated addressing only computational measures of accuracy, without investigating the usefulness of recommendations in realistic tasks. The aim of this work is to synthesize the research in this area through a novel approach by (1) demonstrating comprehensive digital activity monitoring, (2) introducing entity-based computing and interaction, and (3) investigating the previously overlooked usefulness of entity recommendations and their actual impact on user behavior in real tasks. The methodology exploits context from screen frames recorded every 2 seconds to recommend information entities related to the current task. We embodied this methodology in an interactive system and investigated the relevance and influence of the recommended entities in a study with participants resuming their real-world tasks after a 14-day monitoring phase. Results show that the recommendations allowed participants to find more relevant entities than in a control without the system. In addition, the recommended entities were also used in the actual tasks. In the discussion, we reflect on a research agenda for entity recommendation in context, revisiting comprehensive monitoring to include the physical world, considering entities as actionable recommendations, capturing drifting intent and routines, and considering explainability and transparency of recommendations, ethics, and ownership of data
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