131,285 research outputs found
Branching ratios and form factors in B0 s → D(∗)− s μ+νν decays
No full textAs a necessary step towards the test of lepton flavor universality provided by the observable R(D(∗) s ) = B(B0 s → D(∗)− s τ +ντ )/B(B0 s → D(∗)− s μ+νμ), the exlusive branching ratios and form factor of its denominator are going to be measured for the first time at an hadron collider
Observations of CP violation in the decays of B0 and B0s mesons to two charged pions or kaons
No full textThe latest measurements of the CP -violation observables in the charmless two-body decays of B0 and B0s mesons are reported. The analysis involves the data collected by the LHCb experiment at a centre-of-mass energy of 13 TeV, corresponding to a total integrated luminosity of 1.9 fb−1. The combination of these results with the previous determinations by LHCb (additional 3.1 fb−1) provides the most precise measurements of these quantities by a single experiment. In particular, time-dependent CP violation is observed for the first time in the B0s sector
Should we lose hope in adjuvant therapy for neuroendocrine tumors?—In response to: Adjuvant therapy following resection of gastroenteropancreatic neuroendocrine tumors provides no recurrence or survival benefit
No full textTherapeutic options in lung neuroendocrine tumors: between established concepts and new hopes
No full textTypical (TC) and atypical (AC) carcinoids are low-grade neuroendocrine tumors (NETs) of the lung and, are neglected diseases in respect of both high-grade NETs of the lung (i.e. small-cell lung cancer and large-cell neuroendocrine carcinoma) and gastroenteropancreatic (GEP)-NETs. AC and TC account for 2 and 0.2% of all thoracic malignancies, respectively, and have a 12.9% chance of metastatic spread at diagnosis, reaching up to 20% during disease history. There are very few trials specifically designed for lung NETs, and therapeutic options are mainly derived by studies carried out in patients with GEP-NETs. We report a case of a patient affected by AC progressed to available standard treatments who received off-label treatment with sunitinib, a well-known multitarget tyrosine-kinase inhibitor with marked antiangiogenic activity, used routinely for the treatment of GEP-NETs. During treatment, the patient required the administration of an alternative schedule to improve tolerability, with benefit, and achieved a partial response according to the RECIST criteria, which is unusual in NETs. We critically reviewed available data supporting the use of somatostatin analogs, chemotherapy, and target therapies (everolimus and sunitinib) in advanced lung NETs. In the review, ongoing trials in lung NETs and future developments in this research field are also discussed
MeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Misura di asimmetria CP nei decadimenti: e ad LHCb
No full textLa fisica del sapore è uno dei settori di ricerca più promettenti per realizzare misure di altissima precisione del Modello Standard e per osservare indirettamente, attraverso i decadimenti mediati dalle interazioni deboli nuove particelle.
L'esperimento LHCb \`e stato progettato per realizzare misure di altissima precisione in questo settore.
Grazie all'alta luminosità integrata disponibile (3 fb \ap{-1}) ed alla elevata sezione d’urto di produzione dei quark charm, LHCb \`e in grado di realizzare misure di una precisione mai raggiunta fino ad ora da altri esperimenti.
In questo lavoro di tesi \`e stata realizzata una misura preliminare della simmetria di violazione di CP, realizzata mediante i decadimenti dei mesoni neutri negli stati finali e .
Per realizzare la misura sono stati selezionati i decadimenti e utilizzando i dati raccolti da LHCb durante il RUN-1 (2010-2012) ed \`e stato sviluppato un modello di adattamento ai dati in grado di misurare la differenza di asimmetria di CP integrate nel tempo nei decadimenti e , .
Il modello \`e stato sviluppato in modo da descrivere le distribuzioni di massa invariante del e del sia per la componente di segnale sia per quelle di fondo ed \`e stato adattato ai dati, per sottrarne i fondi e misurare le asimmetrie e , corrispondenti alla differenza tra il numero di eventi di segnale e , diviso la loro somma.
La differenza di queste asimmetrie corrisponde a , la cui misura, non ufficiale, \`e stata determinata essere .
Questo risultato rappresenta la miglior misura al mondo mai realizzata da un singolo esperimento
Development of a MCP-based timing layer for the Upgrade 2 of the LHCb experiment
No full textThe High-Luminosty LHC era will provide remarkable opportunities for the physics program of the LHCb experiment. However, various technological challenges are currently open. Concerning the electromagnetic calorimeter, the mea- surement of the time of arrival of the impinging particles will be a crucial new feature to effectively deal with the foreseen high pile-up. A dedicated timing layer, based on LAPPD technology, is currently under investigation for this purpose. This pro- ceeding summarises the motivations for this option and the state of the art of the ongoing R&D programme
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