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Continuous deck bridges of prestressed concrete beams are a type of bridge widely used in Peruvian engineering, due to the advantages that these bridges represent in the optimization of resources in the design and construction stages. The present investigation proposes simplified expressions in two directions of analysis to calculate the fundamental period of vibration of the bridge and the elastic seismic responses of lateral displacement, shear force, and a bending moment of the pier with the highest seismic demand. These expressions were obtained from the elastic seismic analysis carried out on a set of parametric models. As a seismic load, seismic design spectra were used according to isoacceleration maps specified in the bridge manual of the Peruvian Ministry of Transportation. Initially, a simplified model formulated that represents the structural elements of the bridge, then the parameters that define it is seismic behavior were identified and a large number of cases of parametric models were generated. The most representative parameters are defined as longitudinal slenderness (H/B), transverse slenderness (H/D), the aspect ratio of the plan (R/L), number of spans (nt), and peak ground acceleration (PGA). To validate the simplified model, results of interest obtained from the proposed model were compared with those obtained from refined structural models carried out in a specialized engineering program, which includes the effects of common supports and seismic stoppers. Finally, the expressions of the simplified method allow estimating seismic responses with errors of less than 10%. Los puentes de tableros de vigas de concreto presforzado son un tipo de puente ampliamente utilizado en la ingeniería peruana, debido a las ventajas que estos puentes representan en la optimización de recursos en las etapas de diseño y construcción. La presente investigación propone expresiones simplificadas en dos direcciones de análisis para calcular el periodo fundamental de vibración del puente y las respuestas sísmicas elásticas tales como el desplazamiento lateral, la fuerza cortante y el momento flector del pilar de mayor demanda sísmica. Estas expresiones se obtienen del análisis sísmico elástico realizado a un conjunto de modelos paramétricos. Como carga sísmica, se utilizaron espectros de diseño sísmico según los mapas de isoaceleraciones especificados en el manual de puentes del Ministerio de transportes del Perú. Inicialmente, se formuló un modelo simplificado que representa los elementos estructurales del puente, luego se identificaron los parámetros que definen su comportamiento sísmico y se generó una familia de casos de modelos paramétricos. Los parámetros más representativos que fueron definidos son: la esbeltez longitudinal (H/B), la esbeltez transversal (H/D), la razón de aspecto de la planta (R/L), el número de tramos (nt), y la máxima aceleración del suelo (PGA).Para validar el modelo simplificado, se compararon las respuestas de interés obtenidos del modelo propuesto con los obtenidos de modelos estructurales refinados realizados en un programa especializado de ingeniería, que incluye los efectos de apoyos comunes y topes sísmicos. Finalmente, las expresiones del método simplificado permiten estimar las respuestas sísmicas con errores menores al 10%.

We start with a review of the pervasiveness of the nearest neighbor search problem and techniques used to solve it along with some experimental results. In the second chapter, we show reductions between two different classes of geometric proximity problems: the nearest neighbor problems to solve the Euclidean minimum spanning tree problem and the farthest neighbor problems to solve the k- centers problem. In the third chapter, we unify spatial partitioning trees under one framework the meta-tree. Finally, we propose a dual tree algorithm for Bichromatic Closest Pair and measure the complexity of batch nearest neighbor search

Plasmonics, the study of light metal interactions, has shown great potential in the fields of spectroscopy, catalysis, medicine, and photovoltaics. There is significant interest in the design of metal nanoparticles that interact with specific wavelengths of light. By changing the size, shape, and metal composition, nanoparticles can be tuned to interact with different regions of the electromagnetic spectrum. Gold and silver are the two most common metals used in plasmonics, but are inefficient in the ultraviolet (UV) wavelength range and expensive. This has driven the research of plasmonics with non-noble metals that support plasmons in the UV and are cost-effective. Aluminum has been widely considered to be the ideal metal to fill this application has favorable plasmonic properties in the UV wavelength range and is cheap. However, Al is difficult to structure at the nanoscale due to its rapidly forming and chemically stable native oxide. Here we report the simple, large scale fabrication of Aluminum nanoparticle antennas. These nanoparticles have plasmon resonances in the UV, visible, near infrared, and infrared wavelengths. We demonstrate the utility of these nanoparticles as substrates for surface-enhanced infrared absorption spectroscopy, a wavelength range that is usually not associated with Aluminum. We also demonstrate that this fabrication technique allows for the fabrication of more complex nanoparticle geometries. These complex nanoparticles geometries have utility in both fundamental studies, and in surface-enhanced spectroscopies. We also demonstrate the potential of magnesium as a plasmonic metal. Magnesium is shown to support plasmon resonances from the UV to near infrared wavelengths. We investigate the plasmonic properties of nanostructured magnesium films and demonstrate that pure magnesium does not support sharp nanoscale features. By alloying magnesium with aluminum, its plasmonic and structural properties are improved.

Anticoagulant therapy with low molecular weight heparins (LMWH) and mechanical compression is considered the gold standard for the prevention of thrombosis. However, evidence exists that LMWHs impair bone metabolism. The aim of this study was therefore to analyse alterations in the expression of M-CSF, VEGF and TGF-ß1 after treatment with enoxaparin in patients with long bone fracture to investigate the effect of LMWH on human fracture healing.A total of 81 patients with long bone fractures were included in the study and divided into two groups. One group comprised patients who received enoxaparin and the other group, patients who did not receive enoxaparin postoperatively. Growth factor levels were analysed in patients' serum and different groups were retrospectively compared.M-CSF serum concentrations were found to be significantly higher only at 48 weeks after surgery in enoxaparin. Mean overall VEGF serum concentration was higher in patients with enoxaparin. TGF-β1 serum concentrations were higher at 48 weeks after surgery in patients with enoxaparin.This is the first comparative systemic measurement of M-CSF, VEGF and TGF-ß1 serum levels in patients with and without enoxaparin after long bone fracture. Significant differences of the expression of the growth factors after enoxaparin therapy were only observed at week 48 after surgery for M-CSF and TGF-ß1.

A new hydraulic gallery was constructed to increase operational resilience and mitigate risks of Emosson hydropower scheme in the Swiss-French Alps. One of the main constraints of the operation is to avoid the overflow of the so called "Corbes" surge chimney during pumping, if the upstream valve is closed. While this scenario is very rare and happened only three times since the commissioning of the dam in 1973, it is considered as a critical issue for operation of the scheme due to the high risk of this event. Different solutions have been studied to avoid the overflow of the surge chimney. However, the safest solution was to create a new gallery bringing water from the top of the surge chimney to the Emosson Reservoir. However, the execution of the new so-called "Corbes" Gallery took place in challenging alpine conditions with difficult access and a very tight schedule.

Résumé

Purpose: To evaluate the safety and efficacy of dexamethasone intravitreal implant (Ozurdex, DEX implant) 0.7 and 0.35 mg in the treatment of patients with diabetic macular edema (DME).Design: Two randomized, multicenter, masked, sham-controlled, phase III clinical trials with identical protocols were conducted. Data were pooled for analysis.Participants: Patients (n = 1048) with DME, best-corrected visual acuity (BCVA) of 20/50 to 20/200 Snellen equivalent, and central retinal thickness (CRT) of ≥300 μm by optical coherence tomography.Methods: Patients were randomized in a 1:1:1 ratio to study treatment with DEX implant 0.7 mg, DEX implant 0.35 mg, or sham procedure and followed for 3 years (or 39 months for patients treated at month 36) at ≤40 scheduled visits. Patients who met retreatment eligibility criteria could be retreated no more often than every 6 months.Main Outcome Measures: The predefined primary efficacy endpoint for the United States Food and Drug Administration was achievement of ≥15-letter improvement in BCVA from baseline at study end. Safety measures included adverse events and intraocular pressure (IOP).Results: Mean number of treatments received over 3 years was 4.1, 4.4, and 3.3 with DEX implant 0.7 mg, DEX implant 0.35 mg, and sham, respectively. The percentage of patients with ≥15-letter improvement in BCVA from baseline at study end was greater with DEX implant 0.7 mg (22.2%) and DEX implant 0.35 mg (18.4%) than sham (12.0%; P ≤ 0.018). Mean average reduction in CRT from baseline was greater with DEX implant 0.7 mg (−111.6 μm) and DEX implant 0.35 mg (−107.9 μm) than sham (−41.9 μm; P < 0.001). Rates of cataract-related adverse events in phakic eyes were 67.9%, 64.1%, and 20.4% in the DEX implant 0.7 mg, DEX implant 0.35 mg, and sham groups, respectively. Increases in IOP were usually controlled with medication or no therapy; only 2 patients (0.6%) in the DEX implant 0.7 mg group and 1 (0.3%) in the DEX implant 0.35 mg group required trabeculectomy.Conclusions: The DEX implant 0.7 mg and 0.35 mg met the primary efficacy endpoint for improvement in BCVA. The safety profile was acceptable and consistent with previous reports.