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We present a pedagogical review of the universal scaling properties displayed by the structure function F_2 at small x and large Q~2 as measured at HERA. We first describe the derivation of the double asymptotic scaling of F_2 fro...
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We present a pedagogical review of the universal scaling properties displayed by the structure function F_2 at small x and large Q~2 as measured at HERA. We first describe the derivation of the double asymptotic scaling of F_2 from the leading-order Altarelli-Parisi equations of perturba-tive QCD. Universal next-to-leading order corrections to scaling are also derived. We explain why the universal scaling behaviour is spoiled when the initial distributions rise too steeply by considering the nonsinglet distribution F_2~p — F_2~n as an explicit example. We then examine the stability of double scaling to the inclusion of higher order singularities, explaining how the perturbative expansion at small x can be reorganized in such a way that each order is given by the sum of a convergent series of contributions which are of arbitrarily high order in the coupling. The wave-like nature of perturbative evolution is then shown to persist throughout almost all the small x region, giving rise asymptotically to double scaling for a wide class of boundary conditions.
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We discuss a test of the generalization power of the methodology used in the determination of parton distribution functions (PDFs). The “future test” checks whether the uncertainty on PDFs, in regions in which they are not const...
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We discuss a test of the generalization power of the methodology used in the determination of parton distribution functions (PDFs). The “future test” checks whether the uncertainty on PDFs, in regions in which they are not constrained by current data, is compatible with future data. The test is performed by using the current optimized methodology for PDF determination, but with a limited dataset, as available in the past, and by checking whether results are compatible within uncertainty with the result found using a current more extensive dataset. We use the future test to assess the generalization power of the NNPDF4.0 unpolarized PDF and the NNPDFpol1.1 polarized PDF methodology. Specifically, we investigate whether the former would predict the rise of the unpolarized proton structure function F2 at small x using only pre-HERA data, and whether the latter would predict the so-called “proton spin crisis” using only pre-EMC data.
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Background A combination of bortezomib (1.3 mg/m<sup>2</sup>), melphalan (5 mg/m<sup>2</sup>), and dexamethasone (40 mg) (BMD), with all three drugs given as a contemporary intravenous administration, was retrospectively evaluated...
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Background A combination of bortezomib (1.3 mg/m<sup>2</sup>), melphalan (5 mg/m<sup>2</sup>), and dexamethasone (40 mg) (BMD), with all three drugs given as a contemporary intravenous administration, was retrospectively evaluated. Patients and methods Fifty previously treated (median 2 previous lines) patients with myeloma (33 relapsed and 17 refractory) were assessed. The first 19 patients were treated with a twice-a-week (days 1, 4, 8, 11, ‘base’ schedule) administration while, in the remaining 31 patients, the three drugs were administered once a week (days 1, 8, 15, 22, ‘weekly’ schedule). Results Side-effects were predictable and manageable, with prominent haematological toxicity, and a better toxic profile in ‘weekly’ schedule (36% versus 66% in ‘base’ schedule). The overall response rate was 62%. After median follow-up of 24.5 months (range 2.7–50 months), the median progression-free survival (PFS) was 21.6 with no difference between the two schedules and the median overall survival (OS) was 33.8 months. Independently from the adopted schedule, we found that also in a cohort of relapsed/refractory patients achieving at least partial remission improved PFS (35.2 versus 9 months) and OS (unreached median versus 18 months). Conclusion Taken together, our observations suggest that BMD is an effective regimen in advanced myeloma patients with acceptable toxicity.
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Phase-contrast mammography is a rising technology where, in addition to X-ray absorption, images show phase and dark-field contrast. Although the use of biopsy markers constitutes a fundamental task in breast examinations, there h...
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Phase-contrast mammography is a rising technology where, in addition to X-ray absorption, images show phase and dark-field contrast. Although the use of biopsy markers constitutes a fundamental task in breast examinations, there has not been any investigation concerning appropriate clips for this technology. We studied the suitability of three markers (Tumark, Somatex Medical Technologies; Hydromark, Mammotome; and Mammostar, Mammotome) for this modality on a laboratory source setup using a chicken breast phantom. The first two clips appeared to be innocuous, whereas Mammostar showed the potential that the non-metallic portion only could be used as a marker for this technique.
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BackgroundTo describe the clinical set-up and evaluate the feasibility of multimodal ultrasound tomography (MUT) for breast imaging.MethodsThirty-two consecutive patients referred for breast imaging and 24 healthy volunteers under...
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BackgroundTo describe the clinical set-up and evaluate the feasibility of multimodal ultrasound tomography (MUT) for breast imaging.MethodsThirty-two consecutive patients referred for breast imaging and 24 healthy volunteers underwent MUT. In the 32 patients, the examination discomfort was compared to that of mammography (n?=?31), handheld ultrasound (HUS) (n?=?27) and magnetic resonance imaging (MRI) (n?=?4) on a scale from 1 (lowest discomfort) to 10 (highest discomfort). MUT investigation time was recorded. Findings automatically detected by MUT were correlated with conventional imaging and biopsy results.ResultsBreast MUT was well tolerated by all 56 participants; 55 bilateral exams were uneventful. During one exam, the digitalisation card failed and the exam was successfully repeated within three days. Mean examination discomfort was 1.6 (range?=?1–5) for MUT, 1.5 (range?=?1–5) for HUS, 5.3 (range?=?3–7) for MRI, and 6.3 (range?=?1–10) for mammography. MUT examination time was 38?±?6?min (mean?±?standard deviation). In the patients referred for breast imaging, MUT detected four lesions and indicated malignancy in three of these cases. These findings were confirmed by additional imaging and biopsy.ConclusionMUT is feasible in a clinical context considering examination time and patient acceptance. These interesting initial diagnostic findings warrant further studies.
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The superparamagnetic iron oxide tracer Sienna+?was introduced as an alternative to the radioisotope 99Tc Nanocoll to preoperatively mark sentinel lymph nodes in breast cancer. As previously reported, this tracer causes susceptibi...
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The superparamagnetic iron oxide tracer Sienna+?was introduced as an alternative to the radioisotope 99Tc Nanocoll to preoperatively mark sentinel lymph nodes in breast cancer. As previously reported, this tracer causes susceptibility artifacts on magnetic resonance imaging (MRI), potentially hampering the diagnostic performance of follow-up breast MRI. This short report illustrates the temporal development of these artifacts in a patient who was followed up at 6, 12, and 18 months after administration of Sienna+?with MRI systems of different magnetic field strengths (1.5?T and 3.0?T) and using an MRI protocol with sequences optimized for artifact reduction. Although the artifacts were severe and predominant at the higher magnetic strength in the early postoperative period, they diminished over time and the image quality could be further improved by adapting the sequences. These findings indicate the possible use of MRI even after administration of a superparamagnetic tracer for post-treatment monitoring in breast cancer.
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Analysis of the interactions of low-risk human papillomavirus type 11 (HPV11) L2 with karyopherin β (Kap β) nuclear import receptors revealed that L2 interacted with Kap β1, Kap β2, and Kap β3 and formed a complex with the Ka...
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Analysis of the interactions of low-risk human papillomavirus type 11 (HPV11) L2 with karyopherin β (Kap β) nuclear import receptors revealed that L2 interacted with Kap β1, Kap β2, and Kap β3 and formed a complex with the Kap α2β1 heterodimer. HPV11 L2 contains two nuclear localization signals (NLSs)—in the N terminus and the C terminus—that could mediate its nuclear import via a classical pathway. Each NLS was functional in vivo, and deletion of both of them abolished L2 nuclear localization. Both NLSs interacted with the viral DNA. Thus, HPV11 L2 can interact with several karyopherins and the viral DNA and may enter the nucleus via multiple pathways.
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Present and future accelerator neutrino beams, designed to studymixing and leptonic CP-violation, will also offer the opportunity to test Standard Model. We investigated the potentialities of superbeams, in particular T2K. The ide...
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Present and future accelerator neutrino beams, designed to studymixing and leptonic CP-violation, will also offer the opportunity to test Standard Model. We investigated the potentialities of superbeams, in particular T2K. The ideal detector would be a liquid-argon one and our analysis can be applied to future experiments, like the proposal for neutrino experiments with the CERN-PS beam.
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In view of the integration of membrane resonators with more complex MEMS structures, we developed a general fabrication procedure for circular shape SiNx membranes using Deep Reactive Ion Etching (DRIE). Large area and high-stress...
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In view of the integration of membrane resonators with more complex MEMS structures, we developed a general fabrication procedure for circular shape SiNx membranes using Deep Reactive Ion Etching (DRIE). Large area and high-stress SiNx membranes were fabricated and used as optomechanical resonators in a Michelson interferometer, where Q values up to 1.3 × 106 were measured at cryogenic temperatures, and in a Fabry-Pérot cavity, where an optical finesse up to 50000 has been observed.
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