Landing Styles Influence Reactive Strength Index without Increasing Risk for Injury

Purpose: Current knee injury prevention and rehabilitation interventions focus on “soft landings” to prevent lower extremity landing misalignments that could predispose the knee to injury when landing “stiff”. However, from a performance perspective, a “soft” landing is not the self-selected (SS) technique chosen during sports performance. The goal of sports performance is often repeated jumps for maximal height while minimizing ground contact time. The purpose of this study was to determine which of three different landing styles; stiff (ST), self-selected (SS), or soft (SF), exhibit safer landing mechanics and greater jumping performance. Subjects: 30 participants (men: 16; women: 14; BMI: 23.75 ± 2.35kg/m2) Methods: Subjects performed five trials of three randomized drop jump landing styles including SF (approx. 60° knee flexion), ST (knees as straight as possible), and SS. Upon landing, subjects were asked to perform a countermovement jump; jumping as high and fast as possible trying to touch the laboratory ceiling. Knee flexion and valgus were measured using a ten-camera, three-dimensional motion capture system (120 Hz). Kinetics were measured by four force plates (960 Hz) and an FScan In-shoe system (100 Hz) synchronized to the motion system. A wireless electromyography (EMG) system was used to measure muscle activity of the glutes, quadriceps, hamstrings, tibialis anterior, and gastrocnemius. Reactive strength index (RSI) was estimated by dividing the height of the vertical jump (as measured by the displacement of the sacrum) during each trial divided by the contact time with the force plates previous to performing the countermovement jump. Multivariate analyses of variance (MANOVA) with post-hoc if appropriate, were used to compare landing mechanics, kinetics, EMG, and reactive strength among landing styles. Results: All landing styles differed in flexion (p \u3c 0.001) but not in valgus. For flexion, SF (116°) \u3e SS (89°) \u3e ST (60°). MANOVAs for RSI showed significant differences for all jumps (p \u3c 0.001) with SS (0.96) showing the highest value, followed by ST (0.93), and SF (0.64). Kinetics showed significant differences between jumps (p \u3c 0.001) with SF (1.34/bw) showing lower forces followed by SS (1.50/bw), and ST (1.81/bw). No differences between jumps were observed for EMG variables. Conclusions: The difference in flexion between landing styles showed all jumps were performed with different landing depths. No particular landing style demonstrated dangerous valgus landing mechanics. SS landing styles seemed to be the appropriate landing style to enhance jumping/landing performance as they exhibited the highest RSI. Clinical Relevance: Sports physical therapists should allow and reinforce each athlete’s landing style and ensure it is performed with no valgus as this would allow the athletes to maximize their reactive forces and subsequent performance

Simulating Physical Phenomena by Quantum Networks

Physical systems, characterized by an ensemble of interacting elementary constituents, can be represented and studied by different algebras of observables or operators. For example, a fully polarized electronic system can be investigated by means of the algebra generated by the usual fermionic creation and annihilation operators, or by using the algebra of Pauli (spin-1/2) operators. The correspondence between the two algebras is given by the Jordan-Wigner isomorphism. As we previously noted similar one-to-one mappings enable one to represent any physical system in a quantum computer. In this paper we evolve and exploit this fundamental concept in quantum information processing to simulate generic physical phenomena by quantum networks. We give quantum circuits useful for the efficient evaluation of the physical properties (e.g, spectrum of observables or relevant correlation functions) of an arbitrary system with Hamiltonian $H$.Comment: 44 pages, 15 psfigur

Unveiling Order behind Complexity: Coexistence of Ferromagnetism and Bose-Einstein Condensation

We present an algebraic framework for identifying the order parameter and the possible phases of quantum systems that is based on identifying the local dimension $N$ of the quantum operators and using the SU(N) group representing the generators of generalized spin-particle mappings. We illustrate this for $N$=3 by presenting for any spatial dimension the exact solution of the bilinear-biquadratic $S$=1 quantum Heisenberg model at a high symmetry point. Through this solution we rigorously show that itinerant ferromagnetism and Bose-Einstein condensation may coexist.Comment: 5 pages, 1 psfigur

Strong asymmetrical inter-specific relationships in food web simulations

In complex ecosystem models, relationships between species include a large number of direct interactions and indirect effects. In order to unveil some simple and better understandable relationships, it is useful to study the asymmetry of inter-specific effects. We present a simple approach for this based on stochastic food web simulations from previous studies. We refer to the Prince William Sound (Gulf of Alaska) marine ecosystem model for illustration. Real data were used to parameterize a dynamical food web model. Through simulations and sensitivity analysis, we determined the strength of the effects between all species. We calculated the asymmetry between the mutual effects species have on each other, and selected the top 5% most asymmetrical interactions. The set of these highly asymmetrical relationships is illustrated by a separate graph in which we calculated the positional importance of the species and correlated this to other independent properties such as population size and trophic position. Results suggest that halibut is the key species dominating this system of asymmetrical interactions, but sablefish and adult arrowtooth flounder also seem to be of high importance. Nearshore demersals display the highest number of connections in the graph of asymmetrical links, suggesting that this trophic group regulates the dynamics of many species in the food web. This approach identifies key interactions and most asymmetrical relationships, potentially increasing the efficiency of management efforts and aiding conservation efforts

Desarrollo de un sistema clínico veterinario utilizando código de repuesta rápida para mejorar la gestión clínica en la veterinaria Pippa Pets

El presente trabajo de investigación tiene como propósito mejorar la gestión clínica de la veterinaria Pippa Pets, puesto que tenía problemas en el manejo de su información, atención y en el control de su inventario, el tipo de investigación fue una pre experimental con diseño de pre test – post test con una muestra de 34 reservas de citas y atenciones, 46 registros de entradas y 38 registro de salidas de productos; para obtener los resultados se desarrolló un sistema clínico veterinario utilizando código de respuesta rápida, para el desarrollo de la investigación se utilizó una mezcla de dos metodologías de desarrollo, RUP para realizar el modelado de negocio correctamente e ICONIX por su simpleza y su garantía de mejora continua del producto para llevar a cabo con éxito la implementación del sistema. Se aplicaron métricas al software para identificar la completitud funcional, la fiabilidad y la usabilidad del software utilizando el test heurístico de Nielsen, el cual arrojó que el software era fácil de usar y amigable para el usuario, se implementó con el sistema el proceso de reservas de citas el cual genera una cita con un código QR minimizando de esa manera el tiempo en la reserva de citas en un 91%, se mejoró el tiempo en la atención, puesto que el tiempo en la búsqueda de información se redujo en un 73%, disminuyó el tiempo del registro de entradas y salidas de productos en un 71% y 72% respectivamente, puesto que se sistematizó el inventario y los productos se identifican a través de un código QR, el nivel de satisfacción del cliente se incrementó en un 20% debido a que la implementación del sistema y el manejo correcto de la información ayudó a añadir un servicio para los clientes de la veterinaria asignándoles un código QR a las mascotas con el cual solo utilizando su celular y/o tablet pueden revisar la información de su mascota, sus vacunaciones y desparasitaciones, en caso de que la mascota se pierda ese collar puede ser leído por un extraño y contactarse con la propietario asignado a la mascota. Se desplegó la aplicación utilizando el servicio de virtualización Azure de Microsoft utilizando una máquina virtual con Windows Server 2012 para desplegar la aplicación web realizada y SQL server express como gestor de datos. Finalmente, en los anexos se muestra las encuestas realizadas y los diagramas de los procesos del negocio aprobados por la veterinaria.The purpose of this research work is to improve the clinical management of the veterinary Pippa Pets, since it had problems in the handling of its information, attention and in the control of its inventory, the type of research was a pre-experimental with design of pre test - post test with a sample of 34 reservations of appointments and attentions, 46 records of entries and 38 record of outputs of products to obtain the results a veterinary clinical system was developed using a rapid response code, for the development of the research was used a mix of two development methodologies, RUP to perform business modeling correctly and ICONIX for its simplicity and its guarantee of continuous product improvement to carry out the successful implementation of the system. Metrics were applied to the software to identify the functional completeness, reliability and usability of the software using the Nielsen heuristic test, which showed that the software was easy to use and friendly for the user, the reservation process was implemented with the system of appointments which generates an appointment with a QR code thus minimizing the time in booking appointments by 91%, the time in the service was improved, since the time in the search for information was reduced by 73% , the time of the registration of product entries and departures was reduced by 71% and 72% respectively, since the inventory was systematized and the products were identified through a QR code, the level of customer satisfaction was increased by 20%. %, because the implementation of the system and the correct handling of the information helped to add a service for the veterinary clients assigning a QR code to the pets with which only use Your cell phone can check your pet's information, vaccinations and deworming, in case the pet is lost that collar can be read by a stranger and contact the owner assigned to the pet. The application was deployed using the Microsoft Azure virtualization service, using a virtual machine with Windows Server to deploy the web application and SQL server express as data manager. Finally, the annexes show the surveys carried out and the diagrams of the business processes approved by the veterinarian

Derecho judicial: el derecho de creación judicial a la luz del siglo XXI

Divulgação dos SUMÁRIOS das obras recentemente incorporadas ao acervo da Biblioteca Ministro Oscar Saraiva do STJ. Em respeito à Lei de Direitos Autorais, não disponibilizamos a obra na íntegra.Localização na estante: 34 D431jOrganizado por: Eduardo de Porres Ortiz de Urbina e Jordan C. Sos

Influencia de la extracción de fluidos de control antes de realizar una prueba de ascenso de presión en un pozo

Llevar a cabo una prueba de ascenso de presión en un pozo, se convierte en una decisión difícil de tomar debido al cierre y a que estos trabajos requieren un procedimiento que implica costos operacionales, sin embargo, se hacen necesarios para obtener información acerca de la formación y del pozo en estudio. Con el fin de disminuir los costos operacionales y obtener un flujo estabilizado antes de realizar el cierre, este trabajo presenta una metodología que puede ser implementada en pozos con bombeo mecánico que se encuentran completados con bomba de subsuelo inserta.  Carry out a buildup pressure test in a wellbore, becomes a difficult decision to make because of the well has to be close and also that this test requires a procedure that involves high operational costs, however, it is needed to obtain information related to the formation and the well in study. With the purpose of reducing operational costs and obtain a stabilized flow before closing the well, this paper presents a methodology that can be implemented in wells with mechanic pump that are completed with a subsurface insert pump

Influencia de la extracción de fluidos de control antes de realizar una prueba de ascenso de presión en un pozo

Llevar a cabo una prueba de ascenso de presión en un pozo, se convierte en una decisión difícil de tomar debido al cierre y a que estos trabajos requieren un procedimiento que implica costos operacionales, sin embargo, se hacen necesarios para obtener información acerca de la formación y del pozo en estudio. Con el fin de disminuir los costos operacionales y obtener un flujo estabilizado antes de realizar el cierre, este trabajo presenta una metodología que puede ser implementada en pozos con bombeo mecánico que se encuentran completados con bomba de subsuelo inserta.  Carry out a buildup pressure test in a wellbore, becomes a difficult decision to make because of the well has to be close and also that this test requires a procedure that involves high operational costs, however, it is needed to obtain information related to the formation and the well in study. With the purpose of reducing operational costs and obtain a stabilized flow before closing the well, this paper presents a methodology that can be implemented in wells with mechanic pump that are completed with a subsurface insert pump

Generalized Jordan-Wigner Transformations

We introduce a new spin-fermion mapping, for arbitrary spin $S$ generating the SU(2) group algebra, that constitutes a natural generalization of the Jordan-Wigner transformation for $S=1/2$. The mapping, valid for regular lattices in any spatial dimension $d$, serves to unravel hidden symmetries in one representation that are manifest in the other. We illustrate the power of the transformation by finding exact solutions to lattice models previously unsolved by standard techniques. We also present a proof of the existence of the Haldane gap in $S=$1 bilinear nearest-neighbors Heisenberg spin chains and discuss the relevance of the mapping to models of strongly correlated electrons. Moreover, we present a general spin-anyon mapping for the case $d \leq 2$.Comment: 5 pages, 1 psfigur