Symmetry fractionalization in the topological phase of the spin-1/2 J(1)-J(2) triangular Heisenberg model

Using density-matrix renormalization-group calculations for infinite cylinders, we elucidate the properties of the spin-liquid phase of the spin-1/2 J(1)-J(2) Heisenberg model on the triangular lattice. We find four distinct ground states characteristic of a nonchiral, Z(2) topologically ordered state with vison and spinon excitations. We shed light on the interplay of topological ordering and global symmetries in the model by detecting fractionalization of time-reversal and space-group dihedral symmetries in the anyonic sectors, which leads to the coexistence of symmetry protected and intrinsic topological order. The anyonic sectors, and information on the particle statistics, can be characterized by degeneracy patterns and symmetries of the entanglement spectrum. We demonstrate the ground states on finite-width cylinders are short-range correlated and gapped; however, some features in the entanglement spectrum suggest that the system develops gapless spinonlike edge excitations in the large-width limit

Antioxidant and antibacterial activities of Cladophora glomerata (L.) Kütz. in Caspian Sea Coast, Iran

Cladophora is one of the largest filamentous green-algal genus and has a widespread distribution in Caspian Sea Coast. This study aimed at assaying the antimicrobial and antioxidant activities of Cladophora glomerata in South of Caspian sea. The antioxidant activity of the extract was investigated, including the total phenolic contents (3077 ± 105 mg gallic acid equivalent g-1 of extract), total flavonoid contents (595 ± 23 mg quercetin equivalent gl-1 of extract), scavenging activity of 2,2-diphenyl-1- picrylhydrazyl (DPPH) radicals (920 ± 42 μg ml-1 as IC50 value), iron chelating activity (IC50 = 971 ± 39 μg ml-1), scavengers of nitric oxide (0.20 ± 0.01 mg ml-1 as IC50) and reducing power. There were significant differences between the extract and vitamin C (P<0.001). Furthermore, antimicrobial activities of the hydroalcoholic extracts of five different gram negative and positive bacteria including Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella typhimurium and Proteus mirabilis were investigated. The extract was primarily screened for their possible antimicrobial effects using disc diffusion methods. The potential antibacterial activities at different concentrations of the extract were elucidated. The extract displayed a variable degree of antimicrobial activities on different bacteria. Among the gram positive bacteria, the S. aureus (with wider zones of inhibition) was found to be more sensitive than B. subtilis. Among the gram negative bacteria, Salmonella enteritidis was found to be more resistant than Proteus vulgaris. Our findings suggest the possibility of using the Cladophora glomerata as a novel source of natural antimicrobial and antioxidant agents for pharmaceutical industries.Key words: Cladophora glomerata, antibacterial activity, antioxidant activity, flavonoid contents, phenolic contents

Breast Cancer Screening in Women with Hereditary or Familial Risk

__Abstract__ We estimated influence of tumor size and number of positive lymph nodes at breast cancer detection on survival in the current era of new system (neo) adjuvant therapies. We showed that early breast cancer detection remains of great influence. Relative 5-year survival was 96%. Early breast cancer detection is accomplished by screening. For women with BRCA1/2 mutation or familial risk breast cancer screening is a widely used and generally accepted effective secondary preventive measure. However, what the most optimal screening strategy is; method and frequency of screening, and appropriate age group, is under discussion. Furthermore, whether earlier breast cancer detection by screening translates in actual survival benefit in these women is until now unknown for this specific group. The Dutch multicenter MRI Screening Study (MRISC), that ran from 1999-2007, screened women with a familial risk or BRCA1/2 mutation with annual mammog

Phase diagram of the spin-1/2 triangular J1-J2 Heisenberg model on a three-leg cylinder

We study the phase diagram of the frustrated Heisenberg model on the triangular lattice with nearest- and next-nearest-neighbor spin-exchange coupling, on three-leg ladders. Using the density-matrix renormalization-group method, we obtain the complete phase diagram of the model, which includes quasi-long-range 120° and columnar order, and a Majumdar-Ghosh phase with short-ranged correlations. All these phases are nonchiral and planar. We also identify the nature of phase transitions

Soliton-potential interaction in the nonlinear Klein-Gordon model

The interaction of solitons with external potentials in nonlinear Klein-Gordon field theory is investigated using an improved model. The presented model has been constructed with a better approximation for adding the potential to the Lagrangian through the metric of background space-time. The results of the model are compared with another model and the differences are discussed.Comment: 14 pages,8 figure

No Tradeoff between Coherence and Sub-Poissonianity for Heisenberg-Limited Lasers

The Heisenberg limit to laser coherence $\mathfrak{C}$ -- the number of photons in the maximally populated mode of the laser beam -- is the fourth power of the number of excitations inside the laser. We generalize the previous proof of this upper bound scaling by dropping the requirement that the beam photon statistics be Poissonian (i.e., Mandel's $Q=0$). We then show that the relation between $\mathfrak{C}$ and sub-Poissonianity ($Q<0$) is win-win, not a tradeoff. For both regular (non-Markovian) pumping with semi-unitary gain (which allows $Q\xrightarrow{}-1$), and random (Markovian) pumping with optimized gain, $\mathfrak{C}$ is maximized when $Q$ is minimized.Comment: This is a companion letter to the manuscript entitled "Optimized Laser Models with Heisenberg-Limited Coherence and Sub-Poissonian Beam Photon Statistics", arxiv:2208.14082. 6 pages, 2 figure