668 research outputs found
a review
Primary total knee arthroplasty (TKA) is a reliable procedure with reproducible long-term results. Nevertheless, there are conditions related to the type of patient or local conditions of the knee that can make it a difficult procedure. The most common scenarios that make it difficult are discussed in this review. These include patients with many previous operations and incisions, and those with severe coronal deformities, genu recurvatum, a stiff knee, extra-articular deformities and those who have previously undergone osteotomy around the knee and those with chronic dislocation of the patella. Each condition is analysed according to the characteristics of the patient, the pre-operative planning and the reported outcomes. When approaching the difficult primary TKA surgeons should use a systematic approach, which begins with the review of the existing literature for each specific clinical situation. Cite this article: Bone Joint J 2015;97-B(10 Suppl A):30–9
Corrosione e protezione del composito Al 6061 T6/Al2O3p in ambiente marino
I compositi a base di alluminio sono materiali tecnologicamente avanzati con elevate proprietà fisicomeccaniche e sono considerati un’alternativa alle sue leghe tradizionali per l’utilizzo in campo marino.Lo scopo di questo lavoro è stato quello di studiare l’influenza di alcuni parametri caratteristicidel composito Al 6061 T6/Al2O3p sul comportamento alla corrosione marina e testare il potere protettivoe antifouling di alcuni rivestimenti organici di nuova generazione, per un impiego in campo navale.I dati ottenuti per il materiale non protetto dai diversi tests, in accordo fra loro, hanno evidenziatoun attacco corrosivo inferiore quando il contenuto di particelle di allumina aumenta e quandoil composito è ottenuto mediante processo di estrusione. In prossimità della fase rinforzante, inoltre,non sono stati evidenziati inneschi di corrosione localizzata, altrimenti presenti nella matrice.Le prove effettuate con coatings a bassa energia di superficie hanno mostrato un marcato effettoanticorrosivo e antivegetativo, in particolare per i rivestimenti siliconici, in grado di incrementaree mantenere le performances del substrato
Amplitude concentration in a phase-modulated spectrum due to femtosecond filamentation
We present a method by which the spectral intensity of an ultrafast laser pulse can be accumulated at selected frequencies by a controllable amount. Using a 4-f pulse shaper we modulate the phase of the frequency components of a femtosecond laser. By inducing femtosecond filamentation with the modulated pulse, we can concentrate the spectral amplitude of the pulse at various frequencies. The phase mask applied by the pulse shaper determines the frequencies for which accumulation occurs, as well as the intensity of the spectral concentration. This technique provides a way to obtain pulses with adjustable amplitude using only phase modulation and the nonlinear response of a medium. This provides a means whereby information which is encoded into spectral phase jumps may be decoded into measurable spectral intensity spikes
Assessing performance of modern Brillouin spectrometers
Brillouin spectroscopy and imaging has experienced a renaissance in recent years seeing vast improvements in methodology and increasing number of applications. With this resurgence has come the development of new spontaneous Brillouin instruments that often tout superior performance compared to established conventional systems such as tandem Fabry-Perot interferometers (TFPI). The performance of these new systems cannot always be thoroughly examined beyond the scope of the intended application, as applications often take precedence in reports. We therefore present evaluation of three modern Brillouin spectrometers: two VIPA-based spectrometers with wavelength-specific notch filters, and one scanning 6-pass TFPI. Performance analysis is presented along with a discussion about the dependence of measurements on excitation laser source and the various susceptibilities of each system
Life Cycle Assessment of Luminescent Solar Concentrators Integrated into a Smart Window
The main goal of this paper is to assess the life cycle environmental impacts of a multifunctional smart window luminescent solar concentrator (SW-LSC) prototype through the application of the Life Cycle Assessment methodology. To the authors' knowledge, this is one of the first studies on the topic. The analysis followed a cradle to gate approach, considering the assembly and maintenance phase as well as the end of life, examined separately through a recycling/landfill scenario. A comparison of the impacts of LSC modules with those of some building-integrated photovoltaic technologies was carried out. Results showed that the global warming potential (100 years) for SW-LSC was 5.91 x 10(3) kg CO2eq and the manufacturing phase had the greatest impact (about 96%). The recycling/landfill scenario results showed the possibility to reduce impacts by an average of 45%. A dominance analysis of SW-LSC components showed that the aluminum frame was the main hotspot (about 60% contribution), followed by the light-shelf (about 19%). Batteries and motors for the shading system were the biggest contributors in the abiotic depletion potential category (36% and 30%, respectively). An alternative scenario, which involved the use of 75% recycled aluminum for the window frame, highlighted the possibility to reduce environmental impacts from 3% to 46%. Finally, the comparison results showed that the LSC modules' impacts were on average 870% lower than that of various PV technologies when compared on the basis of m(2); on the contrary, LSC modules had the highest impacts in all categories (from 200% to 1900%) when compared with other PV technologies on the basis of 1 kWh of energy generated. The results could be used for the definition of eco-design strategies for the examined device, in order to support the scaling-up process and to put "greener" systems onto the market
Evaluation of cerebrospinal fluid pressure by a formula and its role in the pathogenesis of glaucoma
structural connectivity analysis in children with segmental callosal agenesis
BACKGROUND AND PURPOSE: Segmental callosal agenesis is characterized by the absence of the intermediate callosal portion. We aimed to evaluate the structural connectivity of segmental callosal agenesis by using constrained spherical deconvolution tractography and connectome analysis. MATERIALS AND METHODS: We reviewed the clinical-radiologic features of 8 patients (5 males; mean age, 3.9 years). Spherical deconvolution and probabilistic tractography were performed on diffusion data. Structural connectivity analysis, including summary network metrics, modularity analysis, and network consistency measures, was applied in 5 patients and 10 age-/sex-matched controls. RESULTS: We identified 3 subtypes based on the position of the hippocampal commissure: beneath the anterior callosal remnant in 3 patients (type I), beneath the posterior callosal remnant in 3 patients (type II), and between the anterior and posterior callosal remnants in 2 patients (type III). In all patients, the agenetic segment corresponded to fibers projecting to the parietal lobe, and segmental Probst bundles were found at that level. Ectopic callosal bundles were identified in 3 patients. Topology analysis revealed reduced global connectivity in patients compared with controls. The network topology of segmental callosal agenesis was more variable across patients than that of the control connectomes. Modularity analysis revealed disruption of the structural core organization in the patients. CONCLUSIONS: Three malformative subtypes of segmental callosal agenesis were identified. Even the absence of a small callosal segment may impact global brain connectivity and modularity organization. The presence of ectopic callosal bundles may explain the greater interindividual variation in the connectomes of patients with segmental callosal agenesis
Plan de negocio de una empresa consultora en gestión de contratos de construcción
Uno de los principales problemas en la ejecución de proyectos de construcción son las controversias por los mayores plazos de ejecución y sobre las contraprestaciones para lograr el objetivo del cliente. Estas controversias se pueden gestionar a través de los mecanismos que los propios contratos estipulan, o por la normativa y la regulación vigente. El presente plan de negocios de una empresa consultora en gestión de contratos de construcción tiene como objetivo principal determinar la rentabilidad y la viabilidad del negocio, basado en que la cantidad de procesos arbitrales por obras de construcción por año en el Perú se ha ido incrementando desde el 2008. Ello nos muestra que existe una tendencia en cuanto a cómo los clientes y los contratistas solucionan sus controversias. Es así cómo lo más recomendable es desplegar una eficiente gestión de contrato, ya sea para mitigar controversias o para estar en mejor posición y capacidad de justificar una determinada posición, ya sea como cliente o contratista. Es por ello por lo que una consultora que ayude a contratistas y clientes a poder dar un juicio de valor, ya sea mediante una evaluación técnica específica o un acompañamiento en la gestión del contrato, se convierte en una oportunidad frente a una problemática existente y que cada vez es más frecuente en los proyectos de construcción en el Perú, tanto en el sector público como el privado. En la medida en que los contratistas y los clientes consideren atractivo gestionar y resolver sus controversias usando las buenas prácticas en la industria, así como metodologías y procedimientos recomendados internacionalmente, la idea de negocio será más atractiva y rentable
Executive functions in children with specific learning disorders: Shedding light on a complex profile through teleassessment
Executive Functions (EFs) are high-order cognitive processes relevant to learning and adaptation and frequently impaired in children with specific learning disorders (SLDs). This study aimed to investigate EFs in children with SLD and explore the role of specific EF-related subprocesses, such as stimuli processing and processing speed. Fifty-seven SLD and 114 typically developing (TD) children, matched for gender and age, completed four tasks measuring response inhibition, interference control, shifting, and updating on a web-based teleassessment platform. The results show that SLD children performed lower in all EF tasks than TD children, regardless of stimulus type and condition. Mediation analyses suggested that differences between the SLD and TD groups are mediated by EF-related subprocesses, offering an interpretative model of EF deficits in children with SLD
CLAPI, une base de données multimodale pour la parole en interaction : apports et dilemmes
Dans cette contribution, nous présentons la base CLAPI développée au laboratoire ICAR dans le contexte de l’évolution des bases de données de langues parlées en France au cours des trente dernières années. Nous détaillons les deux composantes de CLAPI, l’archive de corpus de langue parlée en interaction audio et vidéo enregistrés dans des situations sociales naturelles variées, et la plateforme d’outils.L’usage et l’apport de CLAPI sont illustrés par deux études. L’une décrit comment la base peut être utilisée pour des travaux de linguistique interactionnelle intégrant la multimodalité (« oh là là ») ; l’autre concerne une recherche combinant données et métadonnées (« trop »). L’article est aussi l’occasion d’un bilan plus général. La mise en perspective montre en effet qu’après la période des questions est venue celle des dilemmes. La période des questions, choix et décisions à toutes sortes de niveaux a accompagné la mise en place des bases de données. L’expérience permet maintenant de mesurer leurs indéniables apports en termes non seulement de quantité de données disponibles (et traitables grâce aux outils), mais aussi de qualité (comme conséquence des exigences de standardisation liées au partage des données). La période des dilemmes nous conduit à nous interroger sur les meilleurs choix à opérer aujourd’hui dans les relations entre la poursuite des recherches sur des corpus variés (et parfois sensibles) et les exigences des bases de données ouvertes.In this contribution, we present the development of the CLAPI by the ICAR Lab in the context of the evolution of the databases of spoken languages in France during the last thirty years. We describe the two components of CLAPI, the archive of corpus of spoken languages in interaction, audio and video, recorded in varied naturally-occurring social situations, and the plateform of tools.The use and the support of CLAPI the research are shown out of two studies. One illustrates how the database can be used for working in an interactional linguistic perspective, including multimodality (“oh là là”); the other concerns a research combining data and metadata (“trop”).The article is also the occasion of a more general assessment. The perspective on the last thirty years shows that after a period of questions came that of dilemmas. The period of questions, choices and decisions at various levels accompanied the implementation of the databases. The experience enables now to measure their undeniable contributions in terms not only of quantity of available data (and possibly dealt with supported by the tools), but also of quality of the data (as a consequence of the requirements of standardization linked to the needs of sharing the data). The period of the dilemmas leads us to wonder about the best choices to be operated today among continuing research on varied corpuses (sometimes delicate) and the requirements of the databases
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