137 research outputs found
Unification of spatiotemporal quantum formalisms: mapping between process and pseudo-density matrices via multiple-time states
We consider the relation between three different approaches to defining
quantum states across several times and locations: the pseudo-density matrix
(PDM), the process matrix, and the multiple-time state approaches. Previous
studies have shown that bipartite two-time states can reproduce the statistics
of bipartite process matrices. Here, we show that the operational scenarios
underlying two-time states can be represented as PDMs, and thereby construct a
mapping from process matrices to PDMs. The existence of this mapping implies
that PDMs can, like the process matrix, model processes with indefinite causal
orders. We illustrate this ability by showing how negativity of the PDM, a
measure of temporal correlations, is activated by creating a quantum-switched
order of operators associated with reset channels. The results contribute to
the unification of quantum models of spatiotemporal states.Comment: 11 pages, 3 figures, Comments are welcom
Expression of chemokine receptors on circulating tumor cells in patients with solid tumors
<p>Abstract</p> <p>Background</p> <p>The study was performed to investigate the expression of chemokine receptors (CR) on circulating tumor cells (CTC), which may be of importance for organ-specific metastases and cancer treatment since CR are potential drug-targets.</p> <p>Methods</p> <p>Blood samples from patients with metastatic carcinoma (MC) or melanoma (MM) were enriched for CTC and expression of CR (CXCR4, CCR6, CCR7 and CCR9) was evaluated by flow cytometry.</p> <p>Results</p> <p>CTC were detected in 49 of 68 patients (72%) [28 MC; 21 MM] with a median number of 3 CTC (range: 1-94)/10 mL of blood. CXCR4 was expressed on CTC in 82% (40/49) of patients [median number 1 CTC/10 mL blood; range 1-14] and CCR6 in 29 patients (59%; median 1, range: 1-14). In MM patients, CCR7 was expressed on CTC in 6 (29%) samples and CCR9 in 12 (57%). A positive correlation between surface expression of CR and organ-specific metastatic pattern was not observed.</p> <p>Conclusions</p> <p>CR were expressed on CTC of patients with solid tumors. Along with our findings, the observation that CR could be involved in CTC proliferation and migration of tumor cells appoints CTC as potential CR-antagonist therapeutic target.</p
Negative enrichment by immunomagnetic nanobeads for unbiased characterization of circulating tumor cells from peripheral blood of cancer patients
BACKGROUND: A limitation of positive selection strategies to enrich for circulating tumor cells (CTCs) is that there might be CTCs with insufficient expression of the surface target marker which may be missed by the procedure. We optimized a method for enrichment, subsequent detection and characterization of CTCs based on depletion of the leukocyte fraction. METHODS: The 2-step protocol was developed for processing 20 mL blood and based on red blood cell lysis followed by leukocyte depletion. The remaining material was stained with the epithelial markers EpCAM and cytokeratin (CK) 7/8 or for the melanoma marker HMW-MAA/MCSP. CTCs were detected by flow cytometry. CTCs enriched from blood of patients with carcinoma were defined as EpCAM+CK+CD45-. CTCs enriched from blood of patients with melanoma were defined as MCSP+CD45-. One-hundred-sixteen consecutive blood samples from 70 patients with metastatic carcinomas (n = 48) or metastatic melanoma (n = 22) were analyzed. RESULTS: CTCs were detected in 47 of 84 blood samples (56%) drawn from carcinoma patients, and in 17 of 32 samples (53%) from melanoma patients. CD45-EpCAM-CK+ was detected in pleural effusion specimens, as well as in peripheral blood samples of patients with NSCLC. EpCAM-CK+ cells have been successfully cultured and passaged longer than six months suggesting their neoplastic origin. This was confirmed by CGH. By defining CTCs in carcinoma patients as CD45-CK+ and/or EpCAM+, the detection rate increased to 73% (61/84). CONCLUSION: Enriching CTCs using CD45 depletion allowed for detection of epithelial cancer cells not displaying the classical phenotype. This potentially leads to a more accurate estimation of the number of CTCs. If detection of CTCs without a classical epithelial phenotype has clinical relevance need to be determined
Fine-Grained Face Swapping via Regional GAN Inversion
We present a novel paradigm for high-fidelity face swapping that faithfully
preserves the desired subtle geometry and texture details. We rethink face
swapping from the perspective of fine-grained face editing, \textit{i.e.,
``editing for swapping'' (E4S)}, and propose a framework that is based on the
explicit disentanglement of the shape and texture of facial components.
Following the E4S principle, our framework enables both global and local
swapping of facial features, as well as controlling the amount of partial
swapping specified by the user. Furthermore, the E4S paradigm is inherently
capable of handling facial occlusions by means of facial masks. At the core of
our system lies a novel Regional GAN Inversion (RGI) method, which allows the
explicit disentanglement of shape and texture. It also allows face swapping to
be performed in the latent space of StyleGAN. Specifically, we design a
multi-scale mask-guided encoder to project the texture of each facial component
into regional style codes. We also design a mask-guided injection module to
manipulate the feature maps with the style codes. Based on the disentanglement,
face swapping is reformulated as a simplified problem of style and mask
swapping. Extensive experiments and comparisons with current state-of-the-art
methods demonstrate the superiority of our approach in preserving texture and
shape details, as well as working with high resolution images at
10241024.Comment: Project page, see http://e4s2022.github.i
Coexistence of ferromagnetism, antiferromagnetism, and superconductivity in magnetically anisotropic (Eu,La)FeAs2
Materials with exceptional magnetism and superconductivity usually conceive
emergent physical phenomena. Here, we investigate the physical properties of
the (Eu,La)FeAs2 system with double magnetic sublattices. The parent EuFeAs2
shows anisotropy-associated magnetic behaviors, such as Eu-related moment
canting and exchange bias. Through La doping, the magnetic anisotropy is
enhanced with ferromagnetism of Eu2+ realized in the overdoped region, and a
special exchange bias of the superposed ferromagnetic/superconducting loop
revealed in Eu0.8La0.2FeAs2. Meanwhile, the Fe-related antiferromagnetism shows
unusual robustness against La doping. Theoretical calculation and 57Fe
M\"ossbauer spectroscopy investigation reveal a doping-tunable dual
itinerant/localized nature of the Fe-related antiferromagnetism. Coexistence of
the Eu-related ferromagnetism, Fe-related robust antiferromagnetism, and
superconductivity is further revealed in Eu0.8La0.2FeAs2, providing a platform
for further exploration of potential applications and emergent physics.
Finally, an electronic phase diagram is established for (Eu,La)FeAs2 with the
whole superconducting dome adjacent to the Fe-related antiferromagnetic phase,
which is of benefit for seeking underlying clues to high-temperature
superconductivity.Comment: 13 pages, 6 figures for the main tex
Ore genesis of the Tieshajie Cu deposit: Implications for Cu mineralization in the Qin-Hang Metallogenic Belt, South China
The Tieshajie Cu deposit, located in the northeastern part of the Qin-Hang Metallogenic Belt (QHMB), South China, has long been regarded as a representative Meso-Neoproterozoic volcanogenic massive sulfide (VMS) deposit. Here we present a hydrothermal titanite U-Pb age, Re-Os and in-situ S-Cu isotope data for chalcopyrite to constrain the timing and ore genesis of the Tieshajie deposit. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) U-Pb dating of titanite from the disseminated Cu ore yielded a weighted mean 206Pb/238U age of 160.1 Âą 4.4 Ma. Chalcopyrite from different ore types has low 187Os/188Os (0.85â3.60) and 187Re/188Os (46.1â614.0) ratios, combined with initial 187Os/188Os (0.74â2.00), excluding a mantle source. A Re-Os isochron age (188 Âą 30 Ma) for five chalcopyrite samples is consistent with the titanite U-Pb age within errors. Moreover, the variations in Cu isotope compositions (δ65Cu: â1.13 to +0.12 â°) and δ34S values (+3.8 to +7.7 â°) of chalcopyrite are inconsistent with those reported from the ancient VMS deposits in previous studies. Therefore, our results are indicative of a Late Jurassic magmatic-hydrothermal origin instead of a VMS origin for the Tieshajie deposit. In combination with previous studies, we propose that the Tieshajie Cu deposit belongs to the distal part of the Mid-Late Jurassic (170â150 Ma) porphyry-skarn Cu mineralization event in the QHMB, likely triggered by the subduction of the Paleo-Pacific plate during the Late Mesozoic. This study also has new insights into the genesis of Cu mineralization in the QHMB and further provides implications for future exploration
Superconductivity in a new layered cobalt oxychalcogenide NaCoSeO with a 3 triangular lattice
Unconventional superconductivity in bulk materials under ambient pressure is
extremely rare among the 3 transition-metal compounds outside the layered
cuprates and iron-based family. It is predominantly linked to highly
anisotropic electronic properties and quasi-two-dimensional (2D) Fermi
surfaces. To date, the only known example of the Co-based exotic superconductor
was the hydrated layered cobaltate, NaCoO yHO, and its
superconductivity is realized in the vicinity of a spin-1/2 Mott state.
However, the nature of the superconductivity in these materials is still an
active subject of debate, and therefore, finding new class of superconductors
will help unravel the mysteries of their unconventional superconductivity. Here
we report the discovery of unconventional superconductivity at 6.3 K in
our newly synthesized layered compound NaCoSeO, in
which the edge-shared CoSe octahedra form [CoSe] layers with a
perfect triangular lattice of Co ions. It is the first 3 transition-metal
oxychalcogenide superconductor with distinct structural and chemical
characteristics. Despite its relatively low , material exhibits
extremely high superconducting upper critical fields, , which
far exceeds the Pauli paramagnetic limit by a factor of 3 - 4. First-principles
calculations show that NaCoSeO is a rare example of
negative charge transfer superconductor. This new cobalt oxychalcogenide with a
geometrical frustration among Co spins, shows great potential as a highly
appealing candidate for the realization of high- and/or unconventional
superconductivity beyond the well-established Cu- and Fe-based superconductor
families, and opened a new field in physics and chemistry of low-dimensional
superconductors
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