Spin Filtering and Entanglement Swapping through Coherent Evolution of a Single Quantum Dot

We exploit the non-dissipative dynamics of a pair of electrons in a large square quantum dot to perform singlet-triplet spin measurement through a single charge detection and show how this may be used for entanglement swapping and teleportation. The method is also used to generate the AKLT ground state, a further resource for quantum computation. We justify, and derive analytic results for, an effective charge-spin Hamiltonian which is valid over a wide range of parameters and agrees well with exact numerical results of a realistic effective-mass model. Our analysis also indicates that the method is robust to choice of dot-size and initialization errors, as well as decoherence introduced by the hyperfine interaction.Comment: 5 pages, 3 figure

Low-control and robust quantum refrigerator and applications with electronic spins in diamond

We propose a general protocol for low-control refrigeration and thermometry of thermal qubits, which can be implemented using electronic spins in diamond. The refrigeration is implemented by a probe, consisting of a network of interacting spins. The protocol involves two operations: (i) free evolution of the probe; and (ii) a swap gate between one spin in the probe and the thermal qubit we wish to cool. We show that if the initial state of the probe falls within a suitable range, and the free evolution of the probe is both unital and conserves the excitation in the $z$-direction, then the cooling protocol will always succeed, with an efficiency that depends on the rate of spin dephasing and the swap gate fidelity. Furthermore, measuring the probe after it has cooled many qubits provides an estimate of their temperature. We provide a specific example where the probe is a Heisenberg spin chain, and suggest a physical implementation using electronic spins in diamond. Here the probe is constituted of nitrogen vacancy (NV) centers, while the thermal qubits are dark spins. By using a novel pulse sequence, a chain of NV centers can be made to evolve according to a Heisenberg Hamiltonian. This proposal allows for a range of applications, such as NV-based nuclear magnetic resonance of photosensitive molecules kept in a dark spot on a sample, and it opens up possibilities for the study of quantum thermodynamics, environment-assisted sensing, and many-body physics

Current Implant Surface Technology: An Examination of Their Nanostructure and Their Influence on Fibroblast Alignment and Biocompatibility

Systematic reviews indicate that breast implant texture confers a protective effect on capsular contracture. Fibroblasts are affected by micro- and nanotopographies. Few previous studies have investigated the inherent topographies of existing breast implants and the surfaces with which body tissue is exposed. Aims: To examine currently available breast implant surfaces at high resolution and evaluate features within their surface that have been demonstrated to influence fibroblast alignment. Methods: Using scanning electron and light microscopy, 5 distinct smooth and textured silicone implants including the Mentor Siltex® (Mentor Corporation, Santa Barbara, Calif) and Allergan Biocell® (Allergan Medical Corporation, Santa Barbara, Calif) surfaces were investigated at high magnification to illustrate their intrinsic surface topographies. Results: The images obtained illustrate remarkable micro- and nanoscale topographies. Each surface produced a distinctive microenvironment capable of influencing cell shape and thus biointegration. These features are illustrated by our unique, high-magnification images. The smooth surface exhibits a shallow, regular, 5-µm period rippled texture that may explain higher reported contracture rates, while the Biocell and Siltex surfaces show 100- to 200-µm deep but random features that have been shown to anchor the implant to breast tissue and reduce contracture. Results allow a cell's eye view of these implants, with an explanation of why these types of topographies influence the success of these implants. Conclusions: We assessed commonly available silicone implants and offer a unique overview into their surface topographies and how they are manufactured. We conclude that these surfaces require modernization. Our findings provide further insight into potential interactions between cellular assemblies and artificial surfaces and may contribute to the development of improved implant surfaces

Patterning of Novel Breast Implant Surfaces by Enhancing Silicone Biocompatibility, Using Biomimetic Topographies

Introduction and Aims: Silicone biocompatibility is dictated by cell-surface interaction and its understanding is important in the field of implantation. The role of surface topography and its associated cellular morphology needs investigation to identify qualities that enhance silicone surface biocompatability. This study aims to create well-defined silicone topographies and examine how breast tissue–derived fibroblasts react and align to these surfaces. Methods: Photolithographic microelectronic techniques were modified to produce naturally inspired topographies in silicone, which were cultured with breast tissue–derived human fibroblasts. Using light, immunofluorescent and atomic force microscopy, the cytoskeletal reaction of fibroblasts to these silicone surfaces was investigated. Results: Numerous, well-defined micron-sized pillars, pores, grooves, and ridges were manufactured and characterized in medical grade silicone. Inimitable immunofluorescent microscopy represented in our high magnification images of vinculin, vimentin, and the actin cytoskeleton highlights the differences in fibroblast adhesion between fabricated silicone surfaces. These unique figures illustrate that fibroblast adhesion and the reactions these cells have to silicone can be manipulated to enhance biointegration between the implant and the breast tissue. An alteration of fibroblast phenotype was also observed, exhibiting the propensity of these surfaces to induce categorical remodeling of fibroblasts. Conclusions: This unique study shows that fibroblast reactions to silicone topographies can be tailored to induce physiological changes in cells. This paves the way for further research necessary to develop more biocompatible constructs capable of eliminating capsular contracture by subverting the foreign body response

Vibration Serviceability Assessment of a Historic Suspension Footbridge

Experimental and numerical studies for the structural and vibration serviceability assessment of a historic suspension footbridge adopting non-invasive surveys and low-cost equipment are presented. Field surveys have been carried out to determine geometric properties, ambient vibration tests have been performed to estimate the dynamic properties, and the dynamic response of the footbridge under the action of a single crossing pedestrian has been recorded. Based on field surveys, a 3D Finite Element model was built and was then calibrated against ambient vibration test results. The experimentally-measured maximum acceleration under the action of one crossing pedestrian is compared with the ones obtained numerically and analytically. Furthermore, vibration serviceability assessment under multi-pedestrian loading is carried out, adopting the simplified procedure recommended by a recent guideline. Results show that low-cost non-invasive dynamic testing is suitable to correctly identify the footbridge vertical natural frequencies and mode shapes, including higher-order ones, and to draw considerations about the state of degradation of the structure. Moreover, the level of vibration under the action of a single pedestrian can be estimated with sufficient accuracy using a simplified loading model, provided that the modal damping ratio is properly tuned

Productivity, quality and economics of four spring wheat (Triticum aestivum L.) cultivars as affected by three cultivation technologies

ArticleManaging farming inputs in wheat production technologies is an issue of paramount importance to attain optimum profitable production. To examine how varying the farming inputs affects the nutrients uptake and productivity of spring wheat (Triticum aestivum L.) cultivars and to determine the economic efficiency of various cultivation technologies, three-year field experiments were laid out at the Russian Research Institute of Agriculture, during the 2015–2017 growing seasons. Experiments were conducted once a year using randomized complete block arranged in a split plot experimental design with three replications, with the cultivation technology treatments (basic, intensive and high intensive technology) as the main plots, and spring wheat cultivars (Zelata, Lubova, Liza and Ester) as the sub-main plots. The highest grain yield (10.8 t ha-1), harvest index (42.9%), gluten content (39.45%) and gluten index (71.17%) observed for spring wheat cultivar Lubova with the moderate application of farming inputs as an intensive cultivation technology. Highest protein content (18.02%) was attained for both intensive and high intensive cultivation technology with the cultivar Lubova, and the highest 1,000 grains weight (46.32 g) was recorded by cultivar Lubova in basic cultivation technology. Applying moderate amount of inputs as an intensive cultivation technology resulted in highest wheat yield and net income

Motivation-based Market Segmentation in Rural Tourism: the Case of Sámán, Iran

Market segmentation is a pivotal and under-investigated issue when evaluating decision-making processes and motivational factors shaping rural tourism. The present study has examined market segmentsof rural tourists in Iran based on their sociodemographic attributes, travel characteristics and preferred leisure activities, profiling rural tourists on the base of their motivational background. The survey results indicated that rural tourism in the study area is a heterogeneous market, whose development depends on general trends in Middle East tourism market. A comprehensive knowledge of rural tourism actors may help formulating appropriate marketing strategies for internal areas destined to tourism growth

A dietary intervention for chronic diabetic neuropathy pain: a randomized controlled pilot study

Background: Diabetic neuropathy is a common and often debilitating condition for which available treatments are limited. Because a low-fat plant-based diet has been shown to improve glycemic control in individuals with type 2 diabetes, we hypothesized that such a diet would reduce painful symptoms of diabetic neuropathy. Methods: In this 20-week pilot study, individuals with type 2 diabetes and painful diabetic neuropathy were randomly assigned to two groups. The intervention group was asked to follow a low-fat, plant-based diet, with weekly classes for support in following the prescribed diet, and to take a vitamin B12 supplement. The control group was asked to take the same vitamin B12 supplement, but received no other intervention. At baseline, midpoint and 20 weeks, clinical, laboratory and questionnaire data were collected. Questionnaires included an analog ‘worst pain’ scale, Michigan Neuropathy Screening Instrument, global impression scale, Short Form McGill Pain Questionnaire, Neuropathy Total Symptom Score, a weekly pain diary and Norfolk Quality of Life Questionnaire. Results: After 20 weeks, body weight change with the intervention was −6.4 kg (95% confidence interval (CI) −9.4 to −3.4, PP=0.03) with the intervention in an effect size analysis. The between-group difference in change in pain, as measured by the McGill pain questionnaire, was −8.2 points (95% CI −16.1 to −0.3, P=0.04). Michigan Neuropathy Screening Instrument questionnaire score change was −1.6 points (95% CI −3.0 to −0.2, P=0.03). Conclusions: Improvements were seen in some clinical and pain measures. This pilot study suggests the potential value of a plant-based diet intervention, including weekly support classes, for treating painful diabetic neuropathy

Discrete Model of Ideological Struggle Accounting for Migration

A discrete in time model of ideological competition is formulated taking into account population migration. The model is based on interactions between global populations of non-believers and followers of different ideologies. The complex dynamics of the attracting manifolds is investigated. Conversion from one ideology to another by means of (i) mass media influence and (ii) interpersonal relations is considered. Moreover a different birth rate is assumed for different ideologies, the rate being assumed to be positive for the reference population, made of initially non-believers. Ideological competition can happen in one or several regions in space. In the latter case, migration of non-believers and adepts is allowed; this leads to an enrichment of the ideological dynamics. Finally, the current ideological situation in the Arab countries and China is commented upon from the point of view of the presently developed mathematical model. The massive forced conversion by Ottoman Turks in the Balkans is briefly discussed.Comment: 24 pages, with 5 figures and 52 refs.; prepared for a Special issue of Advances in Complex System