Large-amplitude driving of a superconducting artificial atom: Interferometry, cooling, and amplitude spectroscopy

Superconducting persistent-current qubits are quantum-coherent artificial atoms with multiple, tunable energy levels. In the presence of large-amplitude harmonic excitation, the qubit state can be driven through one or more of the constituent energy-level avoided crossings. The resulting Landau-Zener-Stueckelberg (LZS) transitions mediate a rich array of quantum-coherent phenomena. We review here three experimental works based on LZS transitions: Mach-Zehnder-type interferometry between repeated LZS transitions, microwave-induced cooling, and amplitude spectroscopy. These experiments exhibit a remarkable agreement with theory, and are extensible to other solid-state and atomic qubit modalities. We anticipate they will find application to qubit state-preparation and control methods for quantum information science and technology.Comment: 13 pages, 5 figure

Breast adenocarcinoma liver metastases, in contrast to colorectal cancer liver metastases, display a non-angiogenic growth pattern that preserves the stroma and lacks hypoxia

Although angiogenesis is a prerequisite for the growth of most human solid tumours, alternative mechanisms of vascularisation can be adopted. We have previously described a non-angiogenic growth pattern in liver metastases of colorectal adenocarcinomas (CRC) in which tumour cells replace hepatocytes at the tumour-liver interface, preserving the liver architecture and co-opting the sinusoidal blood vessels. The aim of this study was to determine whether this replacement pattern occurs during liver metastasis of breast adenocarcinomas (BC) and whether the lack of an angiogenic switch in such metastases is due to the absence of hypoxia and subsequent vascular fibrinogen leakage. The growth pattern of 45 BC liver metastases and 28 CRC liver metastases (73 consecutive patients) was assessed on haematoxylin- and eosin-stained tissue sections. The majority of the BC liver metastases had a replacement growth pattern (96%), in contrast to only 32% of the CRC metastases (P<0.0001). The median carbonic anhydrase 9 (CA9) expression (M75 antibody), as a marker of hypoxia, (intensity x % of stained tumour cells) was 0 in the BC metastases and 53 in the CRC metastases (P<0.0001). There was CA9 expression at the tumour-liver interface in only 16% of the BC liver metastases vs 54% of the CRC metastases (P=0.002). There was fibrin (T2G1 antibody) at the tumour-liver interface in only 21% of the BC metastases vs 56% of the CRC metastases (P=0.04). The median macrophage count (Chalkley morphometry; KP-1 anti-CD68 antibody) at the interface was 4.3 and 7.5, respectively (P<0.0001). Carbonic anhydrase 9 score and macrophage count were positively correlated (r=0.42; P=0.002) in all metastases. Glandular differentiation was less in the BC liver metastases: 80% had less than 10% gland formation vs only 7% of the CRC metastases (P<0.0001). The liver is a densely vascularised organ and can host metastases that exploit this environment by replacing the hepatocytes and co-opting the vasculature. Our findings confirm that a non-angiogenic pattern of liver metastasis indeed occurs in BC, that this pattern of replacement growth is even more prevalent than in CRC, and that the process induces neither hypoxia nor vascular leakage

Drawing firmer conclusions: autistic children show no evidence of a local processing bias in a controlled copying task

Drawing tasks are frequently used to test competing theories of visuospatial skills in autism. Yet, methodological differences between studies have led to inconsistent findings. To distinguish between accounts based on local bias or global deficit, we present a simple task that has previously revealed dissociable local/global impairments in neuropsychological patients. Autistic and typical children copied corner elements, arranged in a square configuration. Grouping cues were manipulated to test whether global properties affected the accuracy of reproduction. All children were similarly affected by these manipulations. There was no group difference in the reproduction of local elements, although global accuracy was negatively related to better local processing for autistic children. These data speak against influential theories of visuospatial differences in autism

Two-pion Bose-Einstein correlations in central Pb-Pb collisions at sNN\sqrt{s_{\rm NN}} = 2.76 TeV

The first measurement of two-pion Bose-Einstein correlations in central Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ TeV at the Large Hadron Collider is presented. We observe a growing trend with energy now not only for the longitudinal and the outward but also for the sideward pion source radius. The pion homogeneity volume and the decoupling time are significantly larger than those measured at RHIC.Comment: 17 pages, 5 captioned figures, 1 table, authors from page 12, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/388

Suppression of charged particle production at large transverse momentum in central Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}} = 2.76 TeV

Inclusive transverse momentum spectra of primary charged particles in Pb-Pb collisions at $\sqrt{s_{_{\rm NN}}}$ = 2.76 TeV have been measured by the ALICE Collaboration at the LHC. The data are presented for central and peripheral collisions, corresponding to 0-5% and 70-80% of the hadronic Pb-Pb cross section. The measured charged particle spectra in $|\eta|<0.8$ and $0.3 < p_T < 20$ GeV/$c$ are compared to the expectation in pp collisions at the same $\sqrt{s_{\rm NN}}$, scaled by the number of underlying nucleon-nucleon collisions. The comparison is expressed in terms of the nuclear modification factor $R_{\rm AA}$. The result indicates only weak medium effects ($R_{\rm AA} \approx$ 0.7) in peripheral collisions. In central collisions, $R_{\rm AA}$ reaches a minimum of about 0.14 at $p_{\rm T}=6$-7GeV/$c$ and increases significantly at larger $p_{\rm T}$. The measured suppression of high-$p_{\rm T}$ particles is stronger than that observed at lower collision energies, indicating that a very dense medium is formed in central Pb-Pb collisions at the LHC.Comment: 15 pages, 5 captioned figures, 3 tables, authors from page 10, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/98

Changes in immunocompetent cells after interstitial laser thermotherapy of breast cancer

To access publisher full text version of this article. Please click on the hyperlink in Additional Links field.BACKGROUND: Local tumour destruction has been shown to give rise to changes in immunocompetent cells. The aim of this study was to describe the effect of interstitial laser thermotherapy (ILT) of breast carcinoma in the tumour and in regional lymph nodes. METHODS: Seventeen women that underwent radical surgical excision after non-radical ILT were studied. ILT was performed at a steady-state temperature of 48°C for 30 min. Surgical excision was performed 12 (6-23) days after ILT. Six patients with breast cancer not treated with ILT before surgery served as controls. Immunohistological reactions were performed on core needle biopsies prior to treatment and on the excised specimens. RESULTS: ILT resulted in more CD8 lymphocytes and CD68 macrophages within the tumour (P < 0.05 and P < 0.01, respectively) and higher counts of CD20 (P < 0.05), CD68 (P < 0.001) and CD83 (P < 0.01) at the tumour border, when compared to pre-treatment values. In the control patients not receiving ILT, CD8 cells increased within the tumour after resection (P < 0.05). With the probable exception of CD25 Foxp3 cells, the presence of cancer in a lymph node influenced the findings in lymph nodes (examined for CD1a, CD25, Foxp3 CD25, CD83 cells). Thus, comparisons between ILT and control patients were restricted to patients without lymph node metastases. In these patients, ILT and resection were followed by a decrease in CD25 Foxp3 lymphocytes (P < 0.05), when compared to surgical resection alone. CONCLUSIONS: ILT induced changes in immunocompetent cells in patients with breast cancer. The stimulation of the immune system is an added feature of ILT in treatment of patients with breast cancer