2,038 research outputs found
Attosecond resolved charging of clusters
Attosecond laser pulses open the door to resolve microscopic electron
dynamics in time. Experiments performed include the decay of a core hole, the
time-resolved measurement of photo ionization and electron tunneling. The
processes investigated share the coherent character of the dynamics involving
very few, ideally one active electron. Here, we introduce a scheme to probe
dissipative multi-electron motion in time. In this context attosecond probing
enables one to obtain information which is lost at later times and cannot be
retrieved by conventional methods in the energy domain due to the incoherent
nature of the dynamics. As a specific example we will discuss the charging of a
rare-gas cluster during a strong femtosecond pulse with attosecond pulses. The
example illustrates the proposed use of attosecond pulses and suggests an
experimental resolution of a controversy about the mechanism of energy
absorption by rare-gas clusters in strong vacuum-ultraviolet (VUV) pulses.Comment: 4 pages, 3 figure
TripAdvisor of healthcare: Opportunities for value creation through patient feedback platforms
The objective of this study is to explore new opportunities for hospitals to use patient feedback platforms (i.e., digital platforms on which patients express their opinions on their care journeys). Patient feedback platforms generate an ever-expanding amount of data on patient experience of care that is currently unused by most hospital or their business intelligence unit. We used the methodological approach of netnography on the negative feedback received by one hospital
combined with interviews to identify the potential value of the data generated by the patient feedback platform.
The main findings are that a digital feedback platform serves as a source of data to indicate: (1)Where to act
(by localizing the negative comments), (2) On what to act (what thematic provides satisfaction and therefore is to be kept; or causes dissatisfaction and thus is to be improved), and (3) How to innovate (ideas about new practices to implement). It becomes evident that the platforms are developing a service to help hospitals make sense of this raw data and that a hospital can use patient feedback from other hospitals to improve their own practices. The first implication of our results is that patient feedback platforms generate a complementary type of feedback (i.e. based on patient perception and not empirical fact), as well as a source of data (i.e., patients’ external spontaneous feedback and not internally controlled survey feedback) for the Business Intelligence unit engaged in the transformation of the hospital towards patient-centered care. The second implication is that these platforms create a feedback network effect (i.e. A patient’s feedback can be used by hospitals other than the focal hospital concerned by that feedback, therefore increasing the overall value of the platform). The third implication is that digital transformation is enabled not only by data generation on the platform but also by data analysis services provided by the third party that runs the platform
On perturbations of Dirac operators with variable magnetic field of constant direction
We carry out the spectral analysis of matrix valued perturbations of
3-dimensional Dirac operators with variable magnetic field of constant
direction. Under suitable assumptions on the magnetic field and on the
pertubations, we obtain a limiting absorption principle, we prove the absence
of singular continuous spectrum in certain intervals and state properties of
the point spectrum. Various situations, for example when the magnetic field is
constant, periodic or diverging at infinity, are covered. The importance of an
internal-type operator (a 2-dimensional Dirac operator) is also revealed in our
study. The proofs rely on commutator methods.Comment: 12 page
Adverse reactions of biological therapies in patients with psoriasis
Psoriasis is a chronic, immune-mediated disorder characterized by well demarcated, erythematous plaques covered by thick, silvery-white scales, most often located on the knees, elbows, sacral area and scalp. It has a significant impact on the patient\u27s quality of life.
Biological therapies revolutionized the treatment of psoriasis vulgaris but there has been concern regarding the use of those agents due to severe adverse reactions reported in patients receiving TNF-α inhibitors for various inflammatory diseases.
The aim of this paper is to review the most important adverse reactions reported in patients receiving biological treatments. The most common and severe side effects associated with biologicals are infections, cardiac adverse reactions, neurologic adverse reactions, lymphomas, non-melanoma skin cancers and hepatobiliary disease
Clusters under strong VUV pulses: A quantum-classical hybrid-description incorporating plasma effects
The quantum-classical hybrid-description of rare-gas clusters interacting
with intense light pulses which we have developed is described in detail. Much
emphasis is put on the treatment of screening electrons in the cluster which
set the time scale for the evolution of the system and form the link between
electrons strongly bound to ions and quasi-free plasma electrons in the
cluster. As an example we discuss the dynamics of an Ar147 cluster exposed to a
short VUV laser pulse of 20eV photon energy.Comment: 8 pages, 9 figure
A sweet deal? Sugarcane, water and agricultural transformation in Sub-Saharan Africa
Globally, the area of sugarcane is rising rapidly in response to growing demands for bioethanol and increased sugar demand for human consumption. Despite considerable diversity in production systems and contexts, sugarcane is a particularly “high impact” crop with significant positive and negative environmental and socio-economic impacts. Our analysis is focused on Sub-Saharan Africa (SSA), which is a critical region for continued expansion, due to its high production potential, low cost of production and proximity, and access, to European markets. Drawing on a systematic review of scientific evidence, combined with information from key informants, stakeholders and a research-industry workshop, we critically assess the impacts of sugarcane development on water, soil and air quality, employment, food security and human health. Our analysis shows that sugarcane production is, in general, neither explicitly good nor bad, sustainable nor unsustainable. The impacts of expansion of sugarcane production on the environment and society depend on the global political economy of sugar, local context, quality of scheme, nature of the production system and farm management. Despite threats from climate change and forthcoming changes in the trade relationship with the European Union, agricultural development policies are driving national and international interest and investment in sugarcane in SSA, with expansion likely to play an important role in sustainable development in the region. Our findings will help guide researchers and policy makers with new insights in understanding the situated environmental and social impacts associated with alternative sugar economy models, production technologies and qualities of management
Bautin-type bifurkations and stability of energy solutions for a delay differential equation modeling leukemia
In [3], [4] a mathematical model of chronic myelogenous leukemia is considered
Second order perturbation theory for embedded eigenvalues
We study second order perturbation theory for embedded eigenvalues of an
abstract class of self-adjoint operators. Using an extension of the Mourre
theory, under assumptions on the regularity of bound states with respect to a
conjugate operator, we prove upper semicontinuity of the point spectrum and
establish the Fermi Golden Rule criterion. Our results apply to massless
Pauli-Fierz Hamiltonians for arbitrary coupling.Comment: 30 pages, 2 figure
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