Joint product numerical range and geometry of reduced density matrices

© 2016, Science China Press and Springer-Verlag Berlin Heidelberg. The reduced density matrices of a many-body quantum system form a convex set, whose three-dimensional projection Θ is convex in R3. The boundary ∂Θ of Θ may exhibit nontrivial geometry, in particular ruled surfaces. Two physical mechanisms are known for the origins of ruled surfaces: symmetry breaking and gapless. In this work, we study the emergence of ruled surfaces for systems with local Hamiltonians in infinite spatial dimension, where the reduced density matrices are known to be separable as a consequence of the quantum de Finetti’s theorem. This allows us to identify the reduced density matrix geometry with joint product numerical range Π of the Hamiltonian interaction terms. We focus on the case where the interaction terms have certain structures, such that a ruled surface emerges naturally when taking a convex hull of Π. We show that, a ruled surface on ∂Θ sitting in Π has a gapless origin, otherwise it has a symmetry breaking origin. As an example, we demonstrate that a famous ruled surface, known as the oloid, is a possible shape of Θ, with two boundary pieces of symmetry breaking origin separated by two gapless lines

Two-dimensional arrays self-assembled via interference of concentration modulation waves in drying solutions

Self-assembling of patterned nanostructures in solution-processed thin films with multiphase block-copolymers is possible. Generation of small and well-defined regular structures directly from single-phase polymer films is challenging. Here, 2-dimensional (2D) patterned array in single-phase polymers was self-assembled by a solution process. One-dimensional spinodal precipitation with a characteristic wavelength was created along a pinned contact line of the drying solution to form a one-dimensional periodic structure (1DPS) via geometry and concentration confinements. The latter was uncovered from the liquid by sequential depinning and repinning of the contact line. A new 1DPS with an inherited phase re-emerged and triggered depinning and repinning. The process was self-repeated and a 2D array formed with a tuneable lattice type and parameters, which was governed by the interference of two concentration-modulated waves.EPSRC Centre for Innovative Manufacturing in Ultra Precision (EP/I033491/1)

Klebsiella pneumoniae is able to trigger epithelial-mesenchymal transition process in cultured airway epithelial cells

The ability of some bacterial pathogens to activate Epithelial-Mesenchymal Transition normally is a consequence of the persistence of a local chronic inflammatory response or depends on a direct interaction of the pathogens with the host epithelial cells. In this study we monitored the abilities of the K. pneumoniae to activate the expression of genes related to EMT-like processes and the occurrence of phenotypic changes in airway epithelial cells during the early steps of cell infection. We describe changes in the production of intracellular reactive oxygen species and increased HIF-1α mRNA expression in cells exposed to K. pneumoniae infection. We also describe the upregulation of a set of transcription factors implicated in the EMT processes, such as Twist, Snail and ZEB, indicating that the morphological changes of epithelial cells already appreciable after few hours from the K. pneumoniae infection are tightly regulated by the activation of transcriptional pathways, driving epithelial cells to EMT. These effects appear to be effectively counteracted by resveratrol, an antioxidant that is able to exert a sustained scavenging of the intracellular ROS. This is the first report indicating that strains of K. pneumoniae may promote EMT-like programs through direct interaction with epithelial cells without the involvement of inflammatory cells

Resistance to autosomal dominant Alzheimer's disease in an APOE3 Christchurch homozygote: a case report.

We identified a PSEN1 (presenilin 1) mutation carrier from the world's largest autosomal dominant Alzheimer's disease kindred, who did not develop mild cognitive impairment until her seventies, three decades after the expected age of clinical onset. The individual had two copies of the APOE3 Christchurch (R136S) mutation, unusually high brain amyloid levels and limited tau and neurodegenerative measurements. Our findings have implications for the role of APOE in the pathogenesis, treatment and prevention of Alzheimer's disease

Diet and ovarian cancer risk: a case–control study in China

This case–control study, conducted in Zhejiang, China during 1999–2000, investigated whether dietary factors have an aetiological association with ovarian cancer. Cases were 254 patients with histologically confirmed epithelial ovary cancer. The 652 controls comprised 340 hospital visitors, 261 non-neoplasm hospital outpatients without long-term diet modifications and 51 women recruited from the community. A validated food frequency questionnaire was used to measure the habitual diet of cases and controls. The risks of ovarian cancer for the dietary factors were assessed by adjusted odds ratios based on multivariate logistic regression analysis, accounting for potential confounding demographic, lifestyle, familial factors and hormonal status, family ovarian cancer history and total energy intake. The ovarian cancer risk declined with increasing consumption of vegetables and fruits but vice versa with high intakes of animal fat and salted vegetables. The adjusted upper quartile odds ratio compared to the lower quartile was 0.24 (0.1–0.5) for vegetables, 0.36 (0.2–0.7) for fruits, 4.6 (2.2–9.3) for animal fat and 3.4 (2.0–5.8) for preserved (salted) vegetables with significant dose-response relationship. The risk of ovarian cancer also appeared to increase for those women preferring fat, fried, cured and smoked food

The apoptotic response in HCT116BAX-/- cancer cells becomes rapidly saturated with increasing expression of a GFP-BAX fusion protein

Abstract Background Many chemotherapeutic agents promote tumor cell death by activating the intrinsic pathway of apoptosis. Intrinsic apoptosis involves permeabilization of the mitochondrial outer membrane and the release of cytochrome c, a process that is controlled by proteins of the BCL2 gene family. Chemoresistance is often associated with abnormalities in concentrations of BCL2 family proteins. Although stoichiometirc interactions between anti-apoptotic and BH3-only BCL2 family proteins have been well documented as affecting cell death, the association between changes in BAX concentration and intrinsic apoptosis are poorly understood. Methods Exogenous GFP-murine Bax fusion constructs were transfected into BAX-deficient HCT116 cells. To titrate the expression of the fusion protein, GFP-BAX was cloned into a tetracycline sensitive expression cassette and cotransfected with a plasmid expressing the rtTA transcription factor into HCT116 BAX-/- cells. Linear expression of the fusion gene was induced with doxycycline and monitored by quantitative PCR and immunoblotting. Cell death was assayed by DAPI staining cells after exposure to indomethacin, and scoring nuclei for condensed chromatin and fragmented nuclei. Results HCT116 BAX-/- cells were resistant to indomethacin, but susceptibility could be recovered in cells expressing a GFP-BAX fusion protein. Titration of GFP-BAX expression revealed that the concentration of BAX required to induce a saturating apoptosis response from baseline, was rapidly achieved. Increased levels of GFP-BAX were unable to stimulate higher levels of cell death. Examination of GFP-BAX distribution before and after indomethacin treatment indicated that BAX protein did not form aggregates when present at sub-lethal concentrations. Conclusion Within the limitations of this experimental system, BAX-dependent apoptosis in HCT116 cells exhibits an all-or-none response depending on the level of BAX protein present. The lack of BAX aggregation at sub-saturation levels suggests that the translocation step of BAX activation may be impaired

Estimation and projection of the national profile of cancer mortality in China: 1991–2005

There are no national-level data on cancer mortality in China since two surveys in 1973-1975 and 1990-1992 (a 10% sample), but ongoing surveillance systems, based on nonrandom selected populations, give an indication as to the trends for major cancers. Based on a log-linear regression model with Poisson errors, the annual rates of change for 10 cancers and all other cancers combined, by age, sex and urban/rural residence were estimated from the data of the surveillance system of the Center for Health Information and Statistics, covering about 10% of the national population. These rates of change were applied to the survey data of 1990-1992 to estimate national mortality in the year 2000, and to make projections for 2005. Mortality rates for all cancers combined, adjusted for age, are predicted to change little between 1991 and 2005 (-0.8% in men and +2.5% in women), but population growth and ageing will result in an increasing number of deaths, from 1.2 to 1.8 million. The largest predicted increases are for the numbers of female breast (+155.4%) and lung cancers (+112.1% in men, +153.5% in women). For these two sites, mortality rates will almost double. Cancer will make an increasing contribution to the burden of diseases in China in the 21st century. The marked increases in risk of cancers of the lung, female breast and large bowel indicate priorities for prevention and control. The increasing trends in young age groups for cancers of the cervix, lung and female breast suggest that their predicted increases may be underestimated, and that more attention should be paid to strategies for their prevention and control

Observation of a ppb mass threshoud enhancement in \psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p}) decay

The decay channel $\psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p})$ is studied using a sample of $1.06\times 10^8$ $\psi^\prime$ events collected by the BESIII experiment at BEPCII. A strong enhancement at threshold is observed in the $p\bar{p}$ invariant mass spectrum. The enhancement can be fit with an $S$-wave Breit-Wigner resonance function with a resulting peak mass of $M=1861^{+6}_{-13} {\rm (stat)}^{+7}_{-26} {\rm (syst)} {\rm MeV/}c^2$ and a narrow width that is $\Gamma<38 {\rm MeV/}c^2$ at the 90% confidence level. These results are consistent with published BESII results. These mass and width values do not match with those of any known meson resonance.Comment: 5 pages, 3 figures, submitted to Chinese Physics