824 research outputs found
Quantum phase transitions in a two-dimensional quantum XYX model: Ground-state fidelity and entanglement
A systematic analysis is performed for quantum phase transitions in a
two-dimensional anisotropic spin 1/2 anti-ferromagnetic XYX model in an
external magnetic field. With the help of an innovative tensor network
algorithm, we compute the fidelity per lattice site to demonstrate that the
field-induced quantum phase transition is unambiguously characterized by a
pinch point on the fidelity surface, marking a continuous phase transition. We
also compute an entanglement estimator, defined as a ratio between the
one-tangle and the sum of squared concurrences, to identify both the
factorizing field and the critical point, resulting in a quantitative agreement
with quantum Monte Carlo simulation. In addition, the local order parameter is
"derived" from the tensor network representation of the system's ground state
wave functions.Comment: 4+ pages, 3 figure
Device-independent quantum secure direct communication with single photon sources
Quantum secure direct communication (QSDC) can directly transmit secrete
messages through quantum channel. Device-independent (DI) QSDC can guarantee
the communication security relying only on the observation of the Bell
inequality violation, but not on any detailed description or trust of the inner
workings of users' devices. In the paper, we propose a DI-QSDC protocol with
practical high-efficient single photon sources. The communication parties
construct the entanglement channel from single photons by adopting the heralded
architecture, which makes the message leakage rate independent of the photon
transmission loss. The secure communication distance and the practical
communication efficiency of the current DI-QSDC protocol are about 6 times and
600 times of those in the original DI-QSDC protocol. Combining with the
entanglement purification, the parties can construct the nearly perfect
entanglement channel and completely eliminate the message leakage. This DI-QSDC
protocol may have important application in future quantum communication field.Comment: 11 pages, 4 figure
Novel potential therapeutic targets of alopecia areata
Alopecia areata (AA) is a non-scarring hair loss disorder caused by autoimmunity. The immune collapse of the hair follicle, where interferon-gamma (IFN-γ) and CD8+ T cells accumulate, is a key factor in AA. However, the exact functional mechanism remains unclear. Therefore, AA treatment has poor efficacy maintenance and high relapse rate after drug withdrawal. Recent studies show that immune-related cells and molecules affect AA. These cells communicate through autocrine and paracrine signals. Various cytokines, chemokines and growth factors mediate this crosstalk. In addition, adipose-derived stem cells (ADSCs), gut microbiota, hair follicle melanocytes, non-coding RNAs and specific regulatory factors have crucial roles in intercellular communication without a clear cause, suggesting potential new targets for AA therapy. This review discusses the latest research on the possible pathogenesis and therapeutic targets of AA
Cavernous Transformation of the Portal Vein Might Increase the Risk of Liver Abscess
Cavernous transformation of the portal vein (CTPV) is not quite common in adults, and cases with CTPV and acute liver abscess are lacking. We report a patient with CTPV inducing extrahepatic and intrahepatic obstruction, finally leading to acute liver abscess due to bile duct infection. We aim to find out the possible relationship between CTPV and acute liver abscess. A 45-year-old female patient was admitted to our hospital for recurrent upper abdominal pain and distension for one year, aggravated with fever for three years. A diagnosis of CTPV and liver abscess was made by 16-slice computed tomography. Effective antibiotics and drainage were used for this patients, and she was eventually cured. When treating patients with CTPV, extrahepatic and intrahepatic obstruction, one should be aware of the presence of acute liver abscess, and empirical antibiotics might be valuable
Metachronous pulmonary and adrenal metastases after liver transplantation for hepatocarcinoma
<p>Abstract</p> <p>Background</p> <p>The worldwide experience of surgical resection for isolated metastasis following liver transplantation (LT) for hepatocellular carcinoma (HCC) is limited.</p> <p>Methods</p> <p>The case of a 60-year-old patient performed successful surgical management for metachronous pulmonary and adrenal metastases from HCC after LT.</p> <p>Results</p> <p>Eighty months after LT, he was presently alive and disease-free with a normal AFP value.</p> <p>Conclusion</p> <p>The case is an interesting report on a somehow indolent metastatic spread of HCC after LT. It should be considered that metachronous metastatic resectable disease, with no data of recurrence at the primary site in an operable patient, is an indication to perform a surgical resection.</p
Relation between quantum illumination and quantum parameter estimation
Quantum illumination (QI) leverages entangled lights to detect the potential
presence of low-reflective objects in a region surrounded by a thermal bath.
Homologously, quantum parameter estimation utilizes non-classical probes to
accurately estimate the value of the unknown parameter(s) of interest in a
system. There appears to be a certain connection between these two areas.
However, they are commonly studied using different figures of merit:
signal-to-noise ratio and quantum Fisher information. In this study, we prove
that the two measures are equivalent to QI in the limit of zero object
reflectivity. We further demonstrate this equivalence by investigating QI
protocols employing non-Gaussian states, which are obtained by de-Gaussifying
the two-mode squeezed vacuum state with photon addition and photon subtraction.
However, our analysis leads to a no-go result which demonstrates that
de-Gaussification operations do not offer an advantage compared to the null
case.Comment: 9 pages,3 figure
catena-Poly[(dichloridozinc)-μ-1-{4-[(1H-imidazol-1-yl)methyl]benzyl}-1H-imidazole-κ2 N 3:N 3′]
The asymmetric unit of the title compound, [ZnCl2(C14H14N4)]n, contains a ZnII ion situated on a twofold rotation axis and one-half of a 1-{4-[(1H-imidazol-1-yl)methyl]benzyl}-1H-imidazole (L) ligand with the benzene ring situated on an inversion center. The ZnII ion is coordinated by two chloride anions and two N atoms from two L ligands in a distorted tetrahedral geometry. The L ligands bridge ZnCl2 fragments into polymeric chains parallel to [20-1]
BurnCalc assessment study of computer-aided individual three-dimensional burn area calculation
BACKGROUND: Accurate estimation of a burned area is crucial to decisions about fluid resuscitation, surgical options, nutritional support, and prognosis. Widely used clinical methods to estimate a burn area are two-dimensional. They do not consider age, sex, body mass, physical deformities, or other relevant factors. Computer-aided methods have improved the accuracy of estimating burned areas by including data analysis and reducing subjective differences. Three-dimensional (3D) scanning allows us to determine body dimensions rapidly and reproducibly. We describe an individualized, cost-efficient, portable 3D scanning system, BurnCalc, that can create an individual 3D model and then calculate body surface area (BSA) and the burn area accurately and quickly. METHODS: The BurnCalc system was validated by verifying the accuracy and stability of BSA calculation. We measured 10 regular objects in experiment 1, using Student’s t-test and the intraclass correlation coefficient (ICC) in the analysis. In experiment 2, artificial paper patches of known dimensions were attached to various parts of the body of 40 volunteers. Their sizes were then calculated using BurnCalc. The BurnCalc data were compared to actually measured values to verify accuracy and stability. Total BSAs of these 40 volunteers were also calculated by BurnCalc and compared to those derived from an accepted formula. In experiment 3, four experts using Chinese Rule-of-Nines or Rule-of-Palms methods calculated the percentages of the total BSA in 17 volunteers. Student’s t-test and ICC, respectively, were used to compare the results obtained with the BurnCalc technique. RESULTS: Statistically, in experiment 1, p = 0.834 and ICC = 0.999, demonstrating that there was no difference between the BurnCalc and real measurements. Also, the hypothesis of null difference among measures (experiment 2) was true because p > 0.05 and ICC = 0.999, indicating that calculations of the total BSA and the burn area were more accurate using the BurnCalc technology. The reliability of the BurnCalc program was 99.9%. In experiment 3, only the BurnCalc method exhibited values of p > 0.05 (p = 0.774) and ICC = 0.999. CONCLUSIONS: BurnCalc technology produced stable, accurate readings, suggesting that BurnCalc could be regarded as a new standard clinical method
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