A measurable force driven by an excitonic condensate

Cataloged from PDF version of article.Free energy signatures related to the measurement of an emergent force (approximate to 10(-9)N) due to the exciton condensate (EC) in Double Quantum Wells are predicted and experiments are proposed to measure the effects. The EC-force is attractive and reminiscent of the Casimir force between two perfect metallic plates, but also distinctively different from it by its driving mechanism and dependence on the parameters of the condensate. The proposed experiments are based on a recent experimental work on a driven micromechanical oscillator. Conclusive observations of EC in recent experiments also provide a strong promise for the observation of the EC-force. (C) 2014 AIP Publishing LLC

Robust ground state and artificial gauge in DQW exciton condensates under weak magnetic field

Cataloged from PDF version of article.An exciton condensate is a vast playground in studying a number of symmetries that are of high interest in the recent developments in topological condensed matter physics. In double quantum wells (DQWs) they pose highly nonconventional properties due to the pairing of non-identical fermions with a spin dependent order parameter. Here, we demonstrate a new feature in these systems: the robustness of the ground state to weak external magnetic field and the appearance of the artificial spinor gauge fields beyond a critical field strength where negative energy pair-breaking quasi particle excitations, i.e. de-excitation pockets (DX-pockets), are created in certain k regions. The DX-pockets are the Kramers symmetry broken analogs of the negative energy pockets examined in the 1960s by Sarma. They respect a disk or a shell-topology in k-space or a mixture between them depending on the magnetic field strength and the electron-hole density mismatch. The Berry connection between the artificial spinor gauge field and the TKNN number is made. This field describes a collection of pure spin vortices in real space when the magnetic field has only inplane components. (C) 2014 Elsevier B.V. All rights reserved

Projections Onto Convex Sets (POCS) Based Optimization by Lifting

Two new optimization techniques based on projections onto convex space (POCS) framework for solving convex and some non-convex optimization problems are presented. The dimension of the minimization problem is lifted by one and sets corresponding to the cost function are defined. If the cost function is a convex function in R^N the corresponding set is a convex set in R^(N+1). The iterative optimization approach starts with an arbitrary initial estimate in R^(N+1) and an orthogonal projection is performed onto one of the sets in a sequential manner at each step of the optimization problem. The method provides globally optimal solutions in total-variation, filtered variation, l1, and entropic cost functions. It is also experimentally observed that cost functions based on lp, p<1 can be handled by using the supporting hyperplane concept

Novel object recognition is not affected by age despite age-related brain changes

Cataloged from PDF version of article.Age-related memory impairments show a progressive decline across lifespan. Studies have demonstrated equivocal results in biological and behavioral outcomes of aging. Thus, in the present study we examined the novel object recognition task at a delay period that has been shown to be impaired in aged rats of two different strains. Moreover, we used a strain of rats, Fisher 344XBrown Norway, which have published age-related biological changes in the brain. Young (10 month old) and aged (28 month old) rats were tested on a standard novel object recognition task with a 50-minute delay period. The data showed that young and aged rats in the strain we used performed equally well on the novel object recognition task and that both young and old rats demonstrated a righthanded side preference for the novel object. Our data suggested that novel object recognition is not impaired in aged rats although both young and old rats have a demonstrated side preference. Thus, it may be that genetic differences across strains contribute to the equivocal results in behavior, and genetic variance likely influences the course of cognitive aging

The effect of vegetation patterns on Aeolian mass flux at regional scale: a wind tunnel study

Although insight on the effect of vegetation pattern on Aeolian mass transport is essential for re-planting degraded land, only limited knowledge on this effect is available. The objective of this research was to understand the effect of vegetation design on the Aeolian mass flux inside a single land unit and at the borders among land units. A simulation of Atriplex halimus shrubs inside a wind tunnel was made, and sand redistribution was measured after the application of 200-230 seconds wind at a speed of 11 ms-1. The study showed that: 1) sediment maximum transport inside a single land unit is related to the neighboring land units and to the vegetation pattern within both the unit itself and the neighboring land units; 2) the effect of neighboring land units includes the protection effect and the ruling of sediment crossing from one land unit to the neighboring land units; 3) for the designing of re-planting of degraded land the ‘streets’ (zones of erosion areas similar to streets) effect need to be considered; and 4) in addition to the general knowledge needed on the effect of vegetation pattern on the erosion and deposition within an area, it is important to have insight on the redistribution of sediment at small scales upon the aim of the project

Effects of factors on direct screw withdrawal resistance in medium density fiberboard and particleboard

An increase in demand on solid wood that is insufficient supply to meet in the world necessarily directed to other engineering materials that could be an alternative to the solid wood. In this context, instead of using solid wood in furniture and construction industry, wood-based panels such as medium density fiberboard (MDF) and particleboard (PB) have become widely used as construction material. Limited research has been done in the field of fastener performance as mechanical properties with different parameters in the joints constructed with these panels. Therefore, in this study, the parameters of screw type, pilot hole, screw orientation, water treatment and adhesives were investigated in MDF and PB. The results indicated that the highest direct screw withdrawal (DSW) resistance was observed in the test blocks applied with PU and the lowest DSW resistance was in the test blocks without a pilot hole drilled in both materials. In addition, MDF in general had better DSW resistance than PB in almost all combinations of the parameters. The treatment of water into MDF and PB test blocks negatively affects the DSW resistance. The DSW resistance in the face orientation was found to be higher than the corresponding ones in the side orientation in both materials

Retrospectively Analysis of Clinical/Pathological and Prognostic Features of Subtypes of Breast Cancer

DergiPark: 379007tmsjAims: Breast cancer is the most common type of cancer among all women across the world, with an incidence of 25.2%. Of all the cancer cases, breast cancer comes second in line after lung cancer. By 6.4% it marks fifth place as the reason for cancer-related-deaths. Therefore new studies on breast cancer are required. We aimed to retrospectively analyze clinical, pathological and prognostic features of cases that were divided into four subgroups based on their hormone receptor and HER-2 conditions. Method: Records of GATA-Oncology Clinic patients who have been diagnosed with breast cancer within years of 2008-2014, were inspected retrospectively. Cases were divided into four subgroups based on their hormone receptor and HER-2 conditions. Missing records were primarily gathered by electronic recording system, also still-missing-information about the patients were provided via phone calls. Collected data has been evaluated with SPSS 15,0. Results: While demographics such as family history and menopausal state were not different among 4 subgroups, triple negative patients tended to have a lower body-mass index and mean age (p=009, p=0.041, respectively). Only 12 patients had advanced disease at diagnosis. A total of 168 patients received chemotherapy. Progression occurred in 41 patients (21.9%) from early phase breast cancer cases that were taken to adjuvant chemotherapy program. Family history had a significant association with recurrence in breast cancer patients (p=0.026). Menopausal state, lymphovascular invasion, lymph node state and stage were not associated with progression. Independent prognostic factors were not obtained with multivariate analysis for disease-free survival. Advanced stage breast cancer patients had a higher tendency to metastasis. Triple negative patients had more drug resistance towards systemic treatment than other subgroups (p lt;0.001). It has been found that full response to anthracycline + taxane regime was less in triple negative patients. Conclusion: In conclusion, there were some differences within our subgroups. Patients of these subgroups should be followed up and treated with different strategies. All subgroups, especially triple negative group, were in need of new effective therapy strategies

Three-Dimensional Laminin Mimetic Peptide Nanofiber Gels for In Vitro Neural Differentiation

The extracellular matrix (ECM) provides biochemical signals and structural support for cells, and its functional imitation is a fundamental aspect of biomaterial design for regenerative medicine applications. The stimulation of neural differentiation by a laminin protein-derived epitope in two-dimensional (2D) and three-dimensional (3D) environments is investigated. The 3D gel system is found to be superior to its 2D counterpart for the induction of neural differentiation, even in the absence of a crucial biological inducer in nerve growth factor (NGF). In addition, cells cultured in 3D gels exhibits a spherical morphology that is consistent with their form under in vivo conditions. Overall, the present study underlines the impact of bioactivity, dimension, and NGF addition, as well as the cooperative effects thereof, on the neural differentiation of PC-12 cells. These results underline the significance of 3D culture systems in the development of scaffolds that closely replicate in vivo environments for the formation of cellular organoid models in vitro. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei