Weak measurements with orbital angular momentum pointer states

Weak measurements are a unique tool for accessing information about weakly interacting quantum systems with minimal back action. Joint weak measurements of single-particle operators with pointer states characterized by a two-dimensional Gaussian distribution can provide, in turn, key information about quantum correlations which can be of relevance for quantum information applications. Here we demonstrate that by employing two-dimensional pointer states endowed with orbital angular momentum (OAM), it is possible to extract weak values of the higher order moments of single-particle operators, an inaccessible quantity with Gaussian pointer states only. We provide a specific example that illustrates the advantages of our method both, in terms of signal enhancement, and information retrieval.Comment: 5 pages, accepted for publication in Phys. Rev. Let

Helico-conical optical beams self-heal

An optical beam is said to be self-healing when, distorted by an obstacle, the beam corrects itself upon propagation. In this letter, we show through experiments supported by numerical simulations, that Helico-conical optical beams (HCOBs) self-heal. We observe the strong resilience of these beams with different types of obstructions, and relate this to the characteristics of their transverse energy flow.Comment: 4 pages, 5 figure

Orbital angular momentum induced beam shifts

We present experiments on Orbital Angular Momentum (OAM) induced beam shifts in optical reflection. Specifically, we observe the spatial Goos-H\"anchen shift in which the beam is displaced parallel to the plane of incidence and the angular Imbert-Fedorov shift which is a transverse angular deviation from the geometric optics prediction. Experimental results agree well with our theoretical predictions. Both beam shifts increase with the OAM of the beam; we have measured these for OAM indices up to 3. Moreover, the OAM couples these two shifts. Our results are significant for optical metrology since optical beams with OAM have been extensively used in both fundamental and applied research.Comment: 7 pages, 7 figure

How orbital angular momentum affects beam shifts in optical reflection

It is well known that reflection of a Gaussian light beam ($\text{TEM}_{00}$) by a planar dielectric interface leads to four beam shifts when compared to the geometrical-optics prediction. These are the spatial Goos-H\"{a}nchen (GH) shift, the angular GH shift, the spatial Imbert-Fedorov (IF) shift and the angular IF shift. We report here, theoretically and experimentally, that endowing the beam with Orbital Angular Momentum (OAM) leads to coupling of these four shifts; this is described by a $4 \times 4$ mixing matrix.Comment: v2 Version accepted for publication in Phys. Rev.

Histological and Immunohistochemical Evaluation of the Efficacy of a New Cosmetic Formulation in the Treatment of Skin Photoaging

Objective. Mechanism of action of cosmetic products is not often studied. The aim of this study is to determine the histological, immunohistochemical, and clinical changes of a new cosmetic formulation. Methods. Prospective, single-blind, patient-controlled, randomized study in 10 volunteers with mild to moderate skin photoaging on the back of their hands. The product was applied on one hand and a standard cream on the other hand, twice a day for three months. Standardized photographs were taken on basal (T0) and final visit (T1) and skin biopsies were performed. Changes on histological and immunohistochemical markers were studied. Subjective clinical changes were determined. Results. After treatment, a 26.3% improvement on epidermal thickness was detected and a significant increase on collagens I and III, elastin, and fibronectin fibers was achieved (p<0.05). As the expression of MMPs remained stable, this improvement of dermal matrix was attributed to the stimulation of their synthesis. A significant clinical improvement on the treated hand was obtained, compared to control hand. Conclusion. This new cosmetic product with combination of three registered technologies (IFC-CAF, WGC, and RetinSphere), focused on regenerating dermal matrix and activating proliferation of skin cells, has shown to be efficient in the reversion of skin photoaging

Actitudes y percepciones de los docentes universitarios en el proceso de adopción de una innovación. La iniciativa OpenCourseWare en la Universidad de Valencia (España)

El proyecto OpenCourseWare, repositorio de recursos educativos en abierto, se inició en la Universidad de Valencia en 2008 y en 2009, sólo incluía 10 asignaturas, ninguna de ellas del área de ciencias de la salud. El objetivo de este trabajo es investigar las actitudes de los docentes de esta área así como sus percepciones con relación a este repositorio para determinar cuáles son las estrategias necesarias para extender su uso. Se parte de la teoría de la difusión de las innovaciones de Rogers (2003) y de un enfoque cualitativo a través del muestreo teórico, entrevistas semiestructuradas y codificación abierta. Los resultados indican la existencia de dos grandes grupos de profesores. Los adoptantes tempranos con una predisposición alta a participar en la iniciativa y con una percepción positiva de sus atributos y los mainstream o corriente principal más reacios a participar y con una percepción negativa respecto a alguno de sus atributos. La identificación de las características de estos dos grandes grupos marca las líneas de acción y de investigación futura en el ámbito del marketing y difusión, formación, sensibilización y motivación para extender el uso del OCW. The OpenCourseWare project, an open learning resource repository, was set up at the University of Valencia between 2008 and 2009. It initially consisted of only 10 subjects, none of which was in the field of health sciences. The objective of this research is to investigate the attitudes and perceptions of teaching staff in the field of health sciences with regard to the project in order to identify strategies to increase its use and expand its coverage. The diffusion of innovations theory as propounded by Rogers is used, along with a qualitative approach using theoretical sampling, semi-structured interviews and open coding. The results indicate the existence of two categories of teaching staff. Firstly, those who adopt an innovation early, have a marked inclination to participate in the initiative and a positive perception of the characteristics of the innovation. Secondly, a larger category of those more reluctant to participate in it and with a negative perception of one or more of its characteristics. Identifying the nature of these two groups provides guidelines for future action and research in the marketing and distribution of such projects, and the training, awareness and motivation required in order to extend the use of OCW

Knowledge of actions of inhaled corticosteroids in patients who did not persist drug treatment early

Objective To evaluate, among new users of inhaled corticosteroids that did not persist treatment, knowledge of inhaled corticosteroids' actions and whether they were instructed on the use of their inhaler. Setting Fifteen community pharmacies in The Netherlands. Methods Patients were interviewed by telephone. Their general practitioners provided diagnostic information and automated dispensing records were retrieved. Main outcome measures Knowledge of patients about the actions of inhaled corticosteroids. Results 230 (80.1%) of 287 patients were willing to participate. The majority (79.1%) of 230 patients was not aware of the anti-inflammatory actions of inhaled corticosteroids. Most patients were instructed on the use of their inhaler, predominantly by their physician (53%) or pharmacy (35.2%). Conclusions Although most patients reported inhaler instruction by at least one health care provider, the majority was unaware of inhaled corticosteroids' actions. Physicians and pharmacists should reconsider the instructions they provide especially to patients who should continuously use inhaled corticosteroids