3,744 research outputs found
Diffractive production of electroweak vector bosons at the LHC
We analyse diffractive electroweak vector boson production in hadronic
collisions and show that the single diffractive W boson production asymmetry in
rapidity is a particularly good observable at the LHC to test the concept of
the flavour symmetric pomeron parton distributions. It may also provide an
additional constraint for the parton distribution functions in the proton.Comment: 7 pages, 5 figure
Min-Max Predictive Control of a Five-Phase Induction Machine
In this paper, a fuzzy-logic based operator is used instead of a traditional cost function for
the predictive stator current control of a five-phase induction machine (IM). The min-max operator
is explored for the first time as an alternative to the traditional loss function. With this proposal,
the selection of voltage vectors does not need weighting factors that are normally used within
the loss function and require a cumbersome procedure to tune. In order to cope with conflicting
criteria, the proposal uses a decision function that compares predicted errors in the torque producing
subspace and in the x-y subspace. Simulations and experimental results are provided, showing how
the proposal compares with the traditional method of fixed tuning for predictive stator current control.Ministerio de Economía y Competitividad DPI 2016-76493-C3-1-R y 2014/425Unión Europea DPI 2016-76493-C3-1-R y 2014/425Universidad de Sevilla DPI 2016-76493-C3-1-R y 2014/42
Synthetic magnetic fluxes on the honeycomb lattice
We devise experimental schemes able to mimic uniform and staggered magnetic
fluxes acting on ultracold two-electron atoms, such as ytterbium atoms,
propagating in a honeycomb lattice. The atoms are first trapped into two
independent state-selective triangular lattices and are further exposed to a
suitable configuration of resonant Raman laser beams. These beams induce hops
between the two triangular lattices and make atoms move in a honeycomb lattice.
Atoms traveling around each unit cell of this honeycomb lattice pick up a
nonzero phase. In the uniform case, the artificial magnetic flux sustained by
each cell can reach about two flux quanta, thereby realizing a cold atom
analogue of the Harper model with its notorious Hofstadter's butterfly
structure. Different condensed-matter phenomena such as the relativistic
integer and fractional quantum Hall effects, as observed in graphene samples,
could be targeted with this scheme.Comment: 12 pages, 14 figure
Noether's Theorem for Control Problems on Time Scales
We prove a generalization of Noether's theorem for optimal control problems
defined on time scales. Particularly, our results can be used for
discrete-time, quantum, and continuous-time optimal control problems. The
generalization involves a one-parameter family of maps which depend also on the
control and a Lagrangian which is invariant up to an addition of an exact delta
differential. We apply our results to some concrete optimal control problems on
an arbitrary time scale.Comment: This is a preprint of a paper whose final and definite form is
published in International Journal of Difference Equations ISSN 0973-6069,
Vol. 9 (2014), no. 1, 87--10
Social Contacts and the Economic Performance of Immigrants: A Panel Study of Immigrants in Germany
Using data from the German Socio-Economic Panel, we examined the impact of social contacts on immigrant occupational status and income. In addition to general social contacts, we also analyzed the effects of bonding (i.e., co-ethnic) and bridging (i.e., interethnic) ties on economic outcomes. Results show that general social contacts have a positive effect on the occupational status and, in particular, annual income of immigrants. We also find that bridging ties with Germans lead to higher occupational status, but not to increased income. These effects remain visible even when social contacts are measured (at least) one year prior to the economic outcomes, as well as when earlier investments in German human capital are considered. Finally, we show that co-ethnic concentration in the region of residence weakly affects economic returns to German language proficiency and schooling.occupational status, social contacts, immigrants, income, panel data
Performance evaluation of the TFD-capable dynamic QoS assurance of HD video streaming in well-dimensioned network
The Traffic Flow Description (TFD) option of the IP protocol is an experimental option, designed by the Authors and described by the IETF’s Internet Draft. This option was intended for signalling for QoS purposes. Knowledge about forthcoming traffic (such as the amount of data that will be transferred in a given period of time) is conveyed in the fields of the option between end-systems. TFD-capable routers on a path (or a multicast tree) between the sender and receiver(s) are able to read this information, process it and use it for bandwidth allocation. If the time horizons are short enough, bandwidth allocation will be performed dynamically. In the paper a performance evaluation of an HD video transmission QoS assured with the use of the TFD option is presented. The analysis was made for a variable number of video streams and a variable number of TCP flows that compete with the videos for the bandwidth of the shared link. Results show that the dynamic bandwidth allocation using the TFD option better assures the QoS of HD video than the classic solution, based on the RSVP protocol
Timed degradation of Mcl-1 controls mitotic cell death
Mitotic arrest can result in cell death through the process of apoptosis. We have shown by live-cell imaging that the ubiquitin-proteasome dependent proteolysis of the apoptotic regulator Mcl-1 under the control of the anaphase-promoting complex or cyclosome (APC/C) provides a timing mechanism that distinguishes prolonged mitotic arrest from normal mitosis
Rituximab as immunotherapy following autologous stem cell transplantation (ASCT) in a 17-year-old boy with diffuse large B cell lymphoma – a case report
SummaryRituximab is a human-mouse chimeric monoclonal antibody with specifity for the CD20 antigen expressed on B-lineage cells.We are reporting a 17-year old boy diagnosed with diffuse large B cell lymphoma, CD20(+). He was treated by standard chemotherapy and megachemotherapy with ASCT. The boy relapsed in the mediastinum and lungs one year after the treatment was completed. He underwent secondary treatment: surgical procedure, chemotherapy and immunotherapy with rituximab, second ASCT and again immunotherapy in the post-transplantation period. No severe complications during the treatment with rituximab were observed except for leukopenia and central venous catheter infection.The CT scans performed one year after the therapy was completed showed regression of changes previously observed
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