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A cost-effective refractive index sensor based on optical fibers with 45° slanted surface at the distal end is presented. The sensors are used to measure refractive index of saline solutions with sensitivities of -136 dBm/RIU.

Etched singlemode-multimode-singlemode (E-SMS) optical fiber structures are evaluated through the immobilization of a chitosan/Fe2O3 absorption layer for the detection of Hg2+ ions in water at concentrations as low as 0.001 µg/mL (1 ppb).

Cost-effective temperature sensors based on optical fibers with slanted surface at the distal end are presented. Fibers polished at 45°, 30°, and 22.5 ° are used to measure temperature ranging from 24 to 240 °C.

Network Function Virtualization (NFV) is one of the main enablers behind the promised improvements in the Fifth Generation (5G) networking era. Thanks to this concept, Network Functions (NFs) are evolving into software components (e.g., Virtual Network Functions (VNFs)) that can be deployed in general-purpose servers following a cloud-based approach. In this way, NFs can be deployed at scale, fulfilling a great variety of service requirements. Unfortunately, the complexity in the management and orchestration of NFV-based networks has increased due to the diverse demands from a growing number of network services. Such complexity calls for an automated and autonomous solution that self adapts to the needs of those network services. In this paper, we propose and compare a Deep Reinforcement Learning (DRL) agent, a classical Proportional–Integral–Derivative (PID) controller, and a Threshold (THD)-based algorithm for autonomously determining the amount of VNF instances to fulfill a service latency requirement without knowing or predicting the expected demand. Finally, we present a comparison of the three approaches in terms of created VNFs and peak latency performed in a discrete event simulator., This research was partially funded by Ctrl App, a research project of the Fund for Scientific Research Flanders (FWO) under grant agreement No. G055619N, and by the European Union's Horizon 2020 research and innovation programme under Grant Agreement No. 101017109 (DAEMON).

BackgroundType 2 diabetes mellitus (T2DM) is a chronic, highly prevalent disease with a significant impact on health. Appropriate treatment requires effective and timely escalation to achieve metabolic control. To evaluate the effectiveness and safety of IDegLira on adults with T2DM previously treated with oral antidiabetics and/or insulin in a real-life setting.MethodsAn observational study in a real-world setting was conducted. Patients were selected from the outpatient clinic of two centers dedicated to specialized diabetes care. Main outcomes were HbA1c, body weight, insulin dose changes, hypoglycemia, and other adverse events.Results67 T2DM patients treated with IDegLira were monitored between 3 and 7 months. At the end of foll ow-up, the median change in HbA1c was -1.05% (CI95% -1.45, -0.65), and a decrease in insulin requirement was also observed (mean difference -10 TDD units (CI95% - 17 to -2.5). No treatment discontinuation was reported, hypoglycemia events were reported in 3 patients at the end of follow-up versus 8 patients at baseline.ConclusionsThis real-life study shows the effectiveness in glycemic control of IDegLira use in T2DM patients who do not achieve goals with other therapies, with an adequate safety profile. The findings need to be confirmed with evaluation of therapeutic results in larger cohorts.

Two competitive fiber optic sensors for the rapid, sensitive, and highly selective detection of mercury in water are designed, fabricated, and evaluated. A wavelength-modulated sensor based on an etched single-mode–multimode–single-mode (E-SMS) optical fiber structure and an intensity-modulated sensor based on fiber optics with a slanted end were fabricated by readily reproducible methods. The sensors were activated with a nanostructured chitosan/maghemite ( CS/Fe2O3 ) composite thin film for the selective detection of mercury ions ( Hg2+ ) in water. The functionalized sensors were implemented to experimentally validate the potential of CS/Fe2O3 thin film for optical sensing of Hg2+ in drinking water. The sensor based on the E-SMS structure exhibited a wavelength-modulated response with a sensitivity of up to 290 pm/(µg/mL), and the sensor based on the slanted end structure showed an intensity-modulated response with a sensitivity of −0.07dBm/(µg/mL) . Validation of the experimental assay method proves the ability to selectively detect chemical interactions as low as 1 ng/mL (one part per billion) of Hg2+ in water for both sensors. The high specificity of the two sensors was demonstrated by evaluating their responses to a number of potentially interfering metal ions in water. These sensors are cost-effective, simple to construct, and easy to implement, which makes them very promising for the on-site detection and monitoring of mercury in bodies of water.

In this paper, cone-shaped optical fibers as point light sources of spherical waves for digital lensless holographic microscopy (DLHM) are developed and evaluated. The resolution characterization of DLHM with cone-shaped fibers was carried out and a comparative analysis with respect to the pinhole illumination system was developed. The results are very encouraging and support the viability of these cone-shape fibers as a technological alternative to the pinhole illumination system for DLHM.

In this work, step-index optical fibers with up to 0.88 numerical aperture (NA) were designed, modeled, fabricated, and tested. Both ray-tracing and wave-optics propagation analysis were utilized to model the NAs that can be achieved for a step-index optical fiber by modifying the cone angle of the fiber tip. Cone-shaped optical fibers with conical semiangles up to 29°, which renders to NAs around 0.88 in air, were fabricated by static etching and tested when utilized as illumination sources.

In this work, etched singlemode-multimode-singlemode (E-SMS) optical fiber structures are evaluated through the implementation of anti-BSA/BSA immunoassay. By tracking the wavelength response, it is found that the E-SMS devices can detect the presence of antiBSA.

Hydraulic fracturing is one of the most common stimulation operations for increasing the productivity of a well. The fracturing fluid is one of the key factors in the operation and must accomplish some special requirements and behavior. The fluid that remains inside the fracture and the reservoir after the fracturing operation is finished, causes severe damage to the proppant pack and the formation, leading to a lower efficiency of the stimulation. This study presents experimental research on adding nanoparticles to a commercial fracturing fluid commonly used for tight gas-condensate reservoirs, aiming to enhance its performance in rheological behavior and its capacity to reduce the formation damage associated with the use of fracturing fluids. Nanoparticles with mean particle sizes of 8 and 19 nm with basic and acidic surface modifications were employed for modifying a commercial fracturing fluid. Rheology tests were performed at pressure and temperature conditions of 1.38 MPa and 104 °C, respectively, for the different nanoparticles at dosages of 100 and 200 mg/L. The improvement of those properties enabled the modification of the original formulation of the fluid, reducing the amount of methanol, one of most expensive and hazardous additives, by up to 33%, and reducing the formation damage by approximately 71%. Furthermore, this modified fluid was evaluated in terms of its impact in the wettability of the rock and its relative permeability to water and oil through static (contact angle measurements) and dynamic tests (relative permeability curves). The modified fracturing fluid showed an excellent capability to improve the water-wettability of the rock and also decreased the relative water permeability by 83%. This work demonstrates the suitability of adding nanoparticles to fracturing fluid for stimulations where it is necessary to reduce the relative permeability of water, acting as a Relative Permeability Modifier (RPM) in a conformance for a fracturing operation.

In this paper, the capabilities of chromatic dispersion compensation of a photonic crystal fiber with a hexagonal distribution of circular air holes was investigated. The vector finite element method with scattering boundary condition was used to analyze a set of configurations of the fiber in which the distance between air holes’ centers was modified. With this method it was possible to obtain the values of chromatic dispersion and confinement factor in the C fiber band. The best suited configurations were tested in a 160 km optical link with a bit rate of 40 Gbps. The performance was evaluated by measuring the bit error rate for a set of 20 channels with channel spacing of 100 GHz. The simulation results showed that is possible to reach values of chromatic dispersion as low as $- 850{{{\rm{ps}}} \over {{\rm{nm}} \middot {\rm{km}}}}$ , confinement losses close to 10−3 dB/km and good BER results in the order of 10−17 for a wavelength of 1550 nm.

An alternative point source for digital lensless holographic microscopy is engineered from a step-index optical fiber. Numerical aperture of 0.88 is achieved with a mechanically solid setup utilized to image bio samples.

In this work, the development and application of a cost-effective and robust digital lensless holographic microscopy (DLHM) system is presented. In the simple architecture of DLHM based on a point source and a digital camera, the production of the former is introduced by means of an engineered step-index optical fiber with a cone-shaped end tip. The conventional and regularly expensive point source in DLHM is produced by means of a high-numerical-aperture microscope objective and a metallic wavelength-sized pinhole. The proposed replacement renders to DLHM additional simplicity of building, in addition to mechanical stability and robustness, and further reduces the cost of the microscope. The simplified cost-effective DLHM architecture is utilized for imaging resolution test targets and samples of human blood and pond water, revealing competitive mechanical stability and trustable phase images of the imaged specimens.

The ultrafast photoinduced processes of salicylidene-2-anthrylamine (2-AntSA) in acetonitrile solution have been investigated using DFT/TD-DFT static electronic structure calculations and excited state ab initio molecular dynamics simulations. Two different isoenergetic enol ground-state structures with suitable geometry for excited state intramolecular proton transfer (ESIPT) where chosen for the excited-state dynamics. The S1 relaxed potential energy profiles for the excited state intramolecular proton transfer and the N[double bond, length as m-dash]C double bond isomerization reactions predict that both reactions occur over an energy barrier and that they are competitive processes in the deactivation of the Franck-Condon state. The photodynamic simulations show that the ESIPT occurs in the femtosecond time scale for both conformers (77 and 213 fs for IA and IIA, respectively) and that the speed is modulated by the ability of the conformers to evolve toward a planar conformation in the S1 state. The trajectories predict two conical intersections which provide nonradiative relaxation pathways to the S0 state. The first one is located in the twisted enol region, where the proton transfer process is unlikely, and only occurs for the conformer IIA in a time scale ≥600 fs. The second conical intersection is located in the cis-keto region, and represents an effective depopulation channel toward the trans-keto form. All our results are in remarkably good agreement with experiments.

Etched optical fiber immunosensors, with and without ITO nanodeposition, have been developed. The performance of these immunosensors has been assessed implementing an immunoassay. The sensitivity of the mmnunosensor increased by a factor of 4 with the ITO nanocoating, whereas the limit of the detection in both types of devices was 0.2 mg/L of antigens in solution. This work was supported in part by the Spanish Ministry of Education and Science-FEDER TEC 2016-78047 and by the Government of Navarre through its projects with references: 2017/PI008, 2016/PC025 and 2016/PC026. Besides, was supported in part by the Colombian Administrative Department of Science, Technology and Innovation - Colciencias, through the Program for national doctorates, calling 617 of 2013, and by the project 'Biosensores a fibra optica para la deteccion rapida de enfermedades' supported by the Universidad Nacional de Colombia (Hermes code 40834).

This work aims to present a ray tracing analysis to determine the numerical aperture of step-index fibers with conical tips. A multi-mode fiber optics is modeled and a ray tracing study is performed in order to obtain an equation for the numerical aperture in terms of the cone angle.

The injection molding process is the most widely used processing technique for polymers. The analysis of residual stresses generated during this process is crucial for the part quality assessment. The present study evaluates the residual stresses in a tensile strength specimen using the simulation software Moldex3D for two polymers, polypropylene and polycarbonate. The residual stresses obtained under a simulated design of experiment were modeled using a robust multivariable regression technique. The results shown that residual stresses could be successfully modeled with a quadratic polynomial fit. For both materials, the lowest level of residual stresses was found at the highest mold temperature and the lowest melting temperature.

In this work, we present a new design of a low loss and high birefringence THz Photonic Crystal Fiber (PCF) made of TOPAS material, featuring a porous core with elliptical holes. The full-vector finite element method was employed to analyze the optical properties such as birefringence, confinement losses, and effective material losses; as well as to study how these parameters are dependent on the geometry of the structure. The simulation results showed confinement losses ≈ 0.06 dB/m when a configuration with high grade of porosity in the core was implemented. At the same time, birefringence values close to 3×10 -2 there were obtained. The proposed design can be fabricated easily using standard stack and draw technique and be used in several applications in the THz region to propagate the radiation.

This study proposes a general procedure to compute the load demand profile from a parking lot where a fleet of buses with electric propulsion mechanisms are charged. Such procedure is divided in three different stages, the first one models the daily energy utilisation of the batteries based on Monte Carlo simulations and route characteristics. The second one models the process in the charging station based on discrete event simulation of queues of buses served by a lot of available chargers. The third step computes the final demand profile in the parking lot because of the charging process based on the power consumption of batteries’ chargers and the utilisation of the available charges. The proposed procedure allows the computation of the number of required batteries’ chargers to be installed in a charging station placed at a parking lot in order to satisfy and ensure the operation of the fleet, the computation of the power demand profile and the peak load and the computation of the general characteristics of electrical infrastructure to supply the power to the station.

Hydrogen peroxide is a precursor to damage mechanisms in numerous applications; its monitoring is important and challenging. The effect of temperature on the performance and durability of a recently developed optical fiber sensors sensitive to the presence of hydrogen peroxide in low concentrations is investigated. The sensors are fabricated by immobilizing Prussian blue within a multilayer of electrostatically self-assembled polyelectrolytes. The sensing principle of this optical electrode relies on the change in the intensity of the reflected light when Prussian white is oxidized back to the blue state due to the presence of hydrogen peroxide. The amplitude of the intensity of the reflected light is found to vary with temperature in a quadratic fashion, but the characteristic response time which correlates with concentration remains constant. Thus the sensing device retains its abilities to determine and quantify the concentration of hydrogen peroxide in a liquid solution. Additionally, the degradation of these fiber sensors when subjected to high temperature is examined. Four optical fiber sensing devices were subjected to different testing conditions and a characterization protocol that included: measurement of the intensity of the cyanide stretch (2150 cm −1 ) via Raman micro spectroscopy; imaging with scanning electron microscopy; and measurement of the presence of iron ions using energy dispersive X-ray spectroscopy. The results show a gradual degradation of the sensing device as a result of progressive desorption of the polyelectrolyte multilayer structure that leads to leaching of the Prussian reagent. This degradation mechanism does not compromise the functionality of the device which is found sufficiently robust for multiple tests at high temperature. The simplicity of this sensing system combined with its relative robustness and reusability make it a good a good candidate for minimally intrusive and localized monitoring of hydrogen peroxide formation in operating PEMFCs.

a b s t r a c t A novel fiber-optic hydrogen peroxide sensing probe was fabricated using chemically deposited ferric fer- rocyanide, often referred to as Prussian blue (PB). The probe features a fast linear response and durability, due to the robustness and purity of the PB film. Potassium ferricyanide was used as a single source pre- cursor in a straightforward chemical deposition of nanostructured PB onto the tip of a multimode optical fiber. Spectroscopic detection of hydrogen peroxide (H2O2) was performed based on the reduction of PB to Prussian white (PW) by agents like ascorbic acid, and oxidation of PW to PB by H2O2. Measurement of H2O2 concentration is based on the changes of the absorption spectrum, under visible light, of PB and PW. The fiber-optic probes exhibit a linear response to concentration on a log-log scale and are found suitable for determining small concentrations of H2O2. Multiple tests were performed to investigate the repeatability and durability of a sensor response and though requiring recalibration, the probes were found to remain functional for an extended period of time. © 2013 Elsevier Ltd. All rights reserved.

a b s t r a c t A sensing probe for hydrogen peroxide (H2O2) in solution at low concentrations has been developed by deposition of Prussian blue dye in a multi-layer structure of polyelectrolytes onto the tip of a multi-mode optical fiber. The sensing mechanism of this optrode (optical electrode) relies on the oxidation of Prussian white (reduced form of Prussian blue) in the presence of hydrogen peroxide. The sensing capabilities of the probe can be recovered by ex situ reduction of Prussian blue to Prussian white using ascorbic acid. A first set of experiments yielded a linear-log relationship between the peak intensity of the reflected light and the concentration of hydrogen peroxide. The intensity of the light, relative to the intensity at immersion, showed an inverse exponential dependency on the time required to reach the saturation for each H2O2 solution tested. Subsequent experiments in which the sensing probe was exposed to H2O2 solutions with different concentrations, showed that only the time-dependent behavior of the intensity of the light remained. Furthermore, the response time for the intensity to reach 63% of its peak value was found to be linearly dependent on the concentration of the H2O2 in a log-log scale. Reproducible results were for H2O2 concentrations ranging from 10 mol L−1 up to the maximum concentration tested

Trabajo presentado en la Eurosensors 2017 Conference. París, 3–6 de septiembre de 2017. An optical fibre refractometer has been developed by etching and deposition of a thin film of indium tin oxide (ITO) on a single-mode-multimode-single-mode (SMS) fibre structure. The interference between modes in this structure is sensitive to the refractive index changes of the surrounding medium, achieving sensitivities of up to 7000 nm/RIU in the 1.333–1.338 RIU range. A salinity sensor has been implemented as a practical application of this proposed structure. Fast Fourier transform (FFT) analysis and tracking of an interference dip were used to monitor the interference between modes obtaining sensitivities of 0.99 nm/PSU and 0.025 rad/PSU, respectively. This work was supported in part by the Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER) (TEC2016-78047-R) and by the Government of Navarre through its projects with references: 2016/PI008, 2016/PC025 and 2016/PC026. As well, it was partially supported by the Colombian Administrative Department of Science, Technology and Innovation - Colciencias, through the Program for national doctorates, calling 617 of 2013.

Organophosphorus compounds (OC) are widely used as pesticides and produce neuromuscular compromise after acute exposure causing paralysis in rib cage muscles. Given the acute respiratory failure in these patients, it is necessary to provide assistance for breathing with mechanical ventilation. According to the World Health Organization, about 20% of poisonings in the world involves organophosphate pesticides [1]. The management of this kind of patient is difficult due to the lack of information concerning the evolution of poisoning and the long time under mechanical ventilatory support. The flaw in determining the ideal moment for patient disconnection of ventilator, not only increases the time attendance but also the probability of death [2]. Therefore, the development of tools to facilitate the dissemination of knowledge about the effect on ventilatory mechanics of poisoning with these compounds contributes significantly to patient treatment. This article describes a learning tool on effect of intoxication over the mechanical ventilation, through of the interaction with different clinical cases of poisoned patients under mechanical ventilation. This tool allows knowing different variables (heart rate, respiratory rate, arterial blood pressure, rapid shallow breathing index, Richmond agitation sedation scale index, PaO2, PaCO2, QT interval, corrected QT interval) that are important in decisions-making during the spontaneous breathing tests.

SummaryAmong breast cancers, triple-negative breast cancer (TNBC) is the most poorly understood and is refractory to current targeted therapies. Using a genetic screen, we identify the PTPN12 tyrosine phosphatase as a tumor suppressor in TNBC. PTPN12 potently suppresses mammary epithelial cell proliferation and transformation. PTPN12 is frequently compromised in human TNBCs, and we identify an upstream tumor-suppressor network that posttranscriptionally controls PTPN12. PTPN12 suppresses transformation by interacting with and inhibiting multiple oncogenic tyrosine kinases, including HER2 and EGFR. The tumorigenic and metastatic potential of PTPN12-deficient TNBC cells is severely impaired upon restoration of PTPN12 function or combined inhibition of PTPN12-regulated tyrosine kinases, suggesting that TNBCs are dependent on the proto-oncogenic tyrosine kinases constrained by PTPN12. Collectively, these data identify PTPN12 as a commonly inactivated tumor suppressor and provide a rationale for combinatorially targeting proto-oncogenic tyrosine kinases in TNBC and other cancers based on their profile of tyrosine-phosphatase activity.

Breast cancer is a collection of diseases with distinct clinical behaviors and underlying genetic causes. Triple-negative breast cancer (TNBC) is a common subtype of breast cancer that confers a particularly poor prognosis and is refractory to current targeted therapies. Unfortunately, the molecular determinants driving this aggressive malignancy are poorly understood. Using an unbiased genetic screen, we have identified a novel tumor suppressor network that governs proliferation and transformation of TNBCs in vitro and in vivo. We define SECT21 as a core component in this network and a commonly inactivated tumor suppressor in TNBC. SECT21 is a potent suppressor of human mammary epithelial cell proliferation and transformation. SECT21 function is frequently compromised in human TNBCs by inactivating mutations, deletion, or loss of protein expression. Mechanistically, SECT21 is a tyrosine phosphatase that suppresses cellular transformation by interacting with and inhibiting several oncogenic receptor tyrosine kinases including HER2, EGFR, and PDGFR. Notably, the tumorigenic and metastatic potential of SECT21-deficient TNBCs is severely impaired by restoring SECT21 function or by inhibiting kinase targets of SECT21, suggesting that TNBCs are dependent on the proto-oncogenic tyrosine kinases constrained by SECT21. Collectively, these data identify SECT21 as a commonly inactivated tumor suppressor and provide a rationale for combinatorially targeting tyrosine kinases in TNBC and other cancers based on their profile of tyrosine phosphatase activity. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr S6-10.

Nanoparticle-based therapeutics with local delivery and external electromagnetic field modulation holds extraordinary promise for soft-tissue cancers such as breast cancer; however, knowledge of the distribution and fate of nanoparticles in vivo is crucial for clinical translation. Here we demonstrate that multiple diagnostic capabilities can be introduced in photothermal therapeutic nanocomplexes by simultaneously enhancing both near-infrared fluorescence and magnetic resonance imaging (MRI). We track nanocomplexes in vivo, examining the influence of HER2 antibody targeting on nanocomplex distribution over 72 h. This approach provides valuable, detailed information regarding the distribution and fate of complex nanoparticles designed for specific diagnostic and therapeutic functions.

In this work, we analyze the spectral properties of locally pressed fiber Bragg gratings (FBGs) written into polarization maintaining fibers. We study the evolution of the spectral response of a FBG written into a PANDA fiber when the central region of the grating is perturbed by a diametrical load. Due to the complex structure of the fiber, a finite element model was carried out to determine the strain distributions generated at the center region of the fiber core, and hence taking the induced change in refractive index as the change in effective refractive index due to the applied load. Once the shifting in Bragg wavelength and the optical principal axes of the loaded region are known, a modified transfer matrix method is applied to calculate the spectral response of the FBG. We have found experimentally and by numerical simulations that the reflected spectra for the grating exhibit a narrow and tunable polarization-dependent spectral hole. The tuning of this spectral hole is dependent of the magnitude and the angle of the applied force over the optical fiber.

The development of an optical fiber refractometer by hydrogen fluoride etching and sputtering deposition of a thin-film of indium tin oxide on a single-mode-multimode-single-mode fiber structure has been analyzed with the aim of improving the sensitivity to the changes of the refractive index (RI) of the external medium. The device is sensitive to the RI changes of the surrounding medium, which can be monitored by tracking the spectral changes of an attenuation band or with a fast Fourier transform (FFT) analysis. By using an optical spectrum analyzer combined with a simple FFT measurement technique, the simultaneous real time monitoring is achieved. The results show that the sensitivity depends on the thin-film thickness. A maximum of 1442 nm/RIU (refractive index unit) in the 1.32–1.35RIUrange has been attained. In addition, a theoretical analysis has been performed, where simu lationsmatched with the experimental results. As a practical appli cation of the developed optical fiber structure, a °Brix (°Bx) sensor has been implemented with a sensitivity of 2.13 nm/°Bx and 0.25 rad/°Bx respectively for wavelength and phase shift detection. This work was supported in part by the Agencia Estatal de Investigacion, in part by Fondo Europeo de Desarrollo Regional (TEC2016-78047-R), in part by the Government of Navarre through its projects with references: 2016/PI008, 2016/PC025, and 2016/PC026, and in part by the Colombian Administrative Department of Science, Technology and Innovation—Colciencias, through the Program for national doctorates, calling 617 of 2013.

In this work we present an in-line fiber-optics sensor for temperature measurements. The sensing probe is a single-mode/single-mode (SM-SM) fiber configuration formed by splicing two sections of SM fibers with a lateral offset, the sensing probe is coated by the sputtering technique using gold. The measurement of the temperature is carried out by monitoring the shift of the interference pattern. This sensor configuration exhibits insensitivity to changes in the refractive index of the external medium, which broadens the range of environments in which the sensor can measure. The temperature sensitivity obtained for this configuration was 5380 nm/°C.