86 research outputs found
Non-adiabatic geometrical quantum gates in semiconductor quantum dots
In this paper we study the implementation of non-adiabatic geometrical
quantum gates with in semiconductor quantum dots. Different quantum information
enconding/manipulation schemes exploiting excitonic degrees of freedom are
discussed. By means of the Aharanov-Anandan geometrical phase one can avoid the
limitations of adiabatic schemes relying on adiabatic Berry phase; fast
geometrical quantum gates can be in principle implementedComment: 5 Pages LaTeX, 10 Figures include
Holonomic quantum gates: A semiconductor-based implementation
We propose an implementation of holonomic (geometrical) quantum gates by
means of semiconductor nanostructures. Our quantum hardware consists of
semiconductor macroatoms driven by sequences of ultrafast laser pulses ({\it
all optical control}). Our logical bits are Coulomb-correlated electron-hole
pairs (excitons) in a four-level scheme selectively addressed by laser pulses
with different polarization. A universal set of single and two-qubit gates is
generated by adiabatic change of the Rabi frequencies of the lasers and by
exploiting the dipole coupling between excitons.Comment: 10 Pages LaTeX, 10 Figures include
Magnetism in Dense Quark Matter
We review the mechanisms via which an external magnetic field can affect the
ground state of cold and dense quark matter. In the absence of a magnetic
field, at asymptotically high densities, cold quark matter is in the
Color-Flavor-Locked (CFL) phase of color superconductivity characterized by
three scales: the superconducting gap, the gluon Meissner mass, and the
baryonic chemical potential. When an applied magnetic field becomes comparable
with each of these scales, new phases and/or condensates may emerge. They
include the magnetic CFL (MCFL) phase that becomes relevant for fields of the
order of the gap scale; the paramagnetic CFL, important when the field is of
the order of the Meissner mass, and a spin-one condensate associated to the
magnetic moment of the Cooper pairs, significant at fields of the order of the
chemical potential. We discuss the equation of state (EoS) of MCFL matter for a
large range of field values and consider possible applications of the magnetic
effects on dense quark matter to the astrophysics of compact stars.Comment: To appear in Lect. Notes Phys. "Strongly interacting matter in
magnetic fields" (Springer), edited by D. Kharzeev, K. Landsteiner, A.
Schmitt, H.-U. Ye
Role of genetic testing for inherited prostate cancer risk: Philadelphia prostate cancer consensus conference 2017
Purpose: Guidelines are limited for genetic testing for prostate cancer (PCA). The goal of this conference was to develop an expert consensus-dri
The Public Repository of Xenografts enables discovery and randomized phase II-like trials in mice
More than 90% of drugs with preclinical activity fail in human trials, largely due to insufficient efficacy. We hypothesized that adequately powered trials of patient-derived xenografts (PDX) in mice could efficiently define therapeutic activity across heterogeneous tumors. To address this hypothesis, we established a large, publicly available repository of well-characterized leukemia and lymphoma PDXs that undergo orthotopic engraftment, called the Public Repository of Xenografts (PRoXe). PRoXe includes all de-identified information relevant to the primary specimens and the PDXs derived from them. Using this repository, we demonstrate that large studies of acute leukemia PDXs that mimic human randomized clinical trials can characterize drug efficacy and generate transcriptional, functional, and proteomic biomarkers in both treatment-naive and relapsed/refractory disease
Learning from Post-project Reviews : A Cross-Case Analysis
Every new product development (NPD) project should not only deliver a successful
new product but also should generate learning for the organization. Postproject
reviews (PPRs) are recognized by both practitioners and academics as an
appropriate mechanism to stimulate and capture learning in NPD teams. However,
relatively few companies use PPRs, and those that do use them often fail to do
so effectively. Although they are widely perceived to be a useful tool,
empirical research on how PPRs are typically organized and the learning that
results is limited. The present article addresses this gap in the extant
knowledge and describes five in-depth case studies, which were conducted at
leading companies in Germany. A detailed investigation was made of how PPRs are
conducted and of the type of learning that can result. Three main sources of
data were used for each case: company documentation, in-depth interviews with
managers responsible for NPD, and observation of an actual PPR. The different
data sources enabled extensive triangulation of data to be conducted and a high
degree of reliability and validity to be achieved. The analysis enabled a number
of key characteristics of the way PPRs are managed to be identified. Various
characteristics of PPRs influence their utility, such as the time at which they
take place and the way discussions are moderated. In addition, the data show
that participants in the discussions at PPRs often use metaphors and stories,
which indicates that PPRs have the potential to generate tacit knowledge.
Interestingly, the data also show that there are various different ways in which
metaphors and stories appear to stimulate discussions on NPD projects. Based on
the cross-case analysis, a wide range of implications are identified.
Researchers need to investigate PPRs further to identify how they can generate
tacit and explicit knowledge and support project-to-project learning. The
generation of tacit knowledge in NPD is a topic that particularly needs further
investigation. The research also led to a range of recommendations for
practitioners. Companies need to strongly communicate the purpose and value of
PPRs, to run them effectively to stimulate the maximum possible learning, and to
disseminate the findings widely. PPRs have the potential to create and transfer
knowledge amongst NPD professionals, but, as they are seldom currently used,
many companies are missing an important opportunity
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