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1.
Opt Express ; 31(13): 21351-21366, 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37381236

RESUMEN

This paper describes experimental analysis of atmospheric channel model of Geostationary Earth Orbit (GEO) satellite-to-ground optical link by utilizing the Laser Utilizing Communication Systems (LUCAS) onboard the optical data relay GEO satellite. Our research work examines the effect of misalignment fading and various atmospheric turbulence conditions. These analytical results clarify that atmospheric channel model is well fitted to theoretical distributions with misalignment fading under various turbulence regimes. We also evaluate several atmospheric channel characteristics, including coherence time, power spectral density and probability of fade, in various turbulence conditions.

2.
Opt Express ; 31(5): 9081-9097, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36860008

RESUMEN

Free-space optical (FSO) systems are compulsory to realize high capacity and interference-free communication links from low-Earth orbit (LEO) satellite constellations as well as spacecraft and space stations to the Earth. To be integrated with high-capacity ground networks, the collected portion of the incident beam should be coupled into an optical fiber. To accurately evaluate the signal-to-noise ratio (SNR) and bit-error rate (BER) performance metrics, the probability density function (PDF) of fiber coupling efficiency (CE) must be determined. Previous studies have experimentally verified the CE PDF for a single-mode fiber, however, there is no such investigation for the CE PDF of a multi-mode fiber (MMF) in a LEO-to-ground FSO downlink. In this paper, for the first time, the CE PDF for a 200-µm MMF is experimentally investigated using data from an FSO downlink from the Small Optical Link for International Space Station (SOLISS) terminal to a 40-cm sub-aperture optical ground station (OGS) supported by a fine-tracking system. An average CE of 5.45 dB was also achieved given that the alignment between SOLISS and OGS was not optimal. In addition, using the angle-of-arrival (AoA) and received power data, the statistical characteristics such as channel coherence time, power spectral density, spectrogram, and PDFs of AoA, beam misalignments, and atmospheric turbulence-induced fluctuations are revealed and compared with the state-of-the-art theoretical background.

3.
Neoplasia ; 32: 100826, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35878454

RESUMEN

Sunitinib is an effective treatment for patients with metastatic Renal Cell Carcinoma (mRCC) but ultimately resistance occurs. The aim of this study was to investigate sunitinib resistance in RCCs and to develop therapeutic combination strategies with targeted radioimmunotherapy (RIT). We studied two RCC models, analyzed Vascular endothelial growth factor (VEGF) and its receptor (VEGFR) and AXL/MET expression and performed therapy studies in Balb/cnu/nu mice combining sunitinib and [177Lu]Lu-cG250 RIT (6.5 MBq/10 µg), specifically targeting RCC cells. pAXL and pMET were expressed in sunitinib-resistant SK-RC-52 and absent in sunitinib-sensitive NU12. NGS evaluation showed that expression of VEGFA, VEGFB, VEGFD, PGF and VEGFR1,2,3 was higher and expression of VEGFC and PDGFA was lower in NU12 than in SK-RC-52. Therapy studies combining sunitinib with [177Lu]Lu-cG250 RIT showed that the best response in mice with "resistant" SK-RC-52 tumors was observed with two cycles of Sunitinib and [177Lu]Lu-cG250 RIT, probably due to increased vascular permeability by sunitinib treatment. In the "sensitive" NU12 model, two cycles of [177Lu]Lu-cG250 RIT and two cycles of combination treatment were equally effective. Enhanced therapeutic efficacy was achieved when two agents ([177Lu]Lu-cG250 RIT and sunitinib) that on their own did not induce satisfactory response levels, are combined. Our findings provide a promising new therapeutic strategy for patients with advanced RCC.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Animales , Línea Celular Tumoral , Ratones , Ratones Desnudos , Radioinmunoterapia , Sunitinib , Factor A de Crecimiento Endotelial Vascular
4.
Eur Urol Oncol ; 5(1): 70-83, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34353775

RESUMEN

BACKGROUND: Non-muscle-invasive bladder cancer (NMIBC) is characterized by frequent recurrences and a risk of progression in stage and grade. Increased knowledge of underlying biological mechanisms is needed. OBJECTIVE: To identify single nucleotide polymorphisms (SNPs) associated with recurrence-free (RFS) and progression-free (PFS) survival in NMIBC. DESIGN, SETTING, AND PARTICIPANTS: We analyzed outcome data from 3400 newly diagnosed NMIBC patients from the Netherlands, the UK, Canada, and Spain. We generated genome-wide germline SNP data using Illumina OmniExpress and Infinium Global Screening Array in combination with genotype imputation. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Cohort-specific genome-wide association studies (GWASs) for RFS and PFS were performed using a Cox proportional hazard model. Results were combined in a fixed-effect inverse-variance weighted meta-analysis. Candidate genes for the identified SNP associations were prioritized using functional annotation, gene-based analysis, expression quantitative trait locus analysis, and transcription factor binding site databases. Tumor expression levels of prioritized genes were tested for association with RFS and PFS in an independent NMIBC cohort. RESULTS AND LIMITATIONS: This meta-analysis revealed a genome-wide significant locus for RFS on chromosome 14 (lead SNP rs12885353, hazard ratio [HR] C vs T allele 1.55, 95% confidence interval [CI] 1.33-1.82, p = 4.0 × 10-8), containing genes G2E3 and SCFD1. Higher expression of SCFD1 was associated with increased RFS (HR 0.70, 95% CI 0.59-0.84, pFDR = 0.003). Twelve other loci were suggestively associated with RFS (p < 10-5), pointing toward 18 additional candidate genes. For PFS, ten loci showed suggestive evidence of association, indicating 36 candidate genes. Expression levels of ten of these genes were statistically significantly associated with PFS, of which four (IFT140, UBE2I, FAHD1, and NME3) showed directional consistency with our meta-analysis results and published literature. CONCLUSIONS: In this first prognostic GWAS in NMIBC, we identified several novel candidate loci and five genes that showed convincing associations with recurrence or progression. PATIENT SUMMARY: In this study, we searched for inherited DNA changes that affect the outcome of non-muscle-invasive bladder cancer (NMIBC). We identified several genes that are associated with disease recurrence and progression. The roles and mechanisms of these genes in NMIBC prognosis should be investigated in future studies.


Asunto(s)
Neoplasias de la Vejiga Urinaria , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Hidrolasas , Masculino , Recurrencia Local de Neoplasia/patología , Pronóstico , Estudios Retrospectivos , Neoplasias de la Vejiga Urinaria/patología
5.
Environ Monit Assess ; 192(3): 171, 2020 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-32040639

RESUMEN

Integration of low-cost air quality sensors with the internet of things (IoT) has become a feasible approach towards the development of smart cities. Several studies have assessed the performance of low-cost air quality sensors by comparing their measurements with reference instruments. We examined the performance of a low-cost IoT particulate matter (PM10 and PM2.5) sensor in the urban environment of Santiago, Chile. The prototype was assembled from a PM10-PM2.5 sensor (SDS011), a temperature and relative humidity sensor (BME280) and an IoT board (ESP8266/Node MCU). Field tests were conducted at three regulatory monitoring stations during the 2018 austral winter and spring seasons. The sensors at each site were operated in parallel with continuous reference air quality monitors (BAM 1020 and TEOM 1400) and a filter-based sampler (Partisol 2000i). Variability between sensor units (n = 7) and the correlation between the sensor and reference instruments were examined. Moderate inter-unit variability was observed between sensors for PM2.5 (normalized root-mean-square error 9-24%) and PM10 (10-37%). The correlations between the 1-h average concentrations reported by the sensors and continuous monitors were higher for PM2.5 (R2 0.47-0.86) than PM10 (0.24-0.56). The correlations (R2) between the 24-h PM2.5 averages from the sensors and reference instruments were 0.63-0.87 for continuous monitoring and 0.69-0.93 for filter-based samplers. Correlation analysis revealed that sensors tended to overestimate PM concentrations in high relative humidity (RH > 75%) and underestimate when RH was below 50%. Overall, the prototype evaluated exhibited adequate performance and may be potentially suitable for monitoring daily PM2.5 averages after correcting for RH.


Asunto(s)
Contaminantes Atmosféricos , Monitoreo del Ambiente , Material Particulado , Animales , Chile , Ciudades , Monitoreo del Ambiente/economía , Monitoreo del Ambiente/instrumentación , Estaciones del Año
6.
Cell Oncol (Dordr) ; 41(5): 555-568, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29956121

RESUMEN

PURPOSE: Genome-wide association studies (GWAS) have led to the identification of a bladder cancer susceptibility variant (rs710521) in a non-coding intergenic region between the TP63 and LEPREL1 genes on chromosome 3q28, suggesting a role in the transcriptional regulation of these genes. In this study, we aimed to functionally characterize the 3q28 bladder cancer risk locus. METHODS: Fine-mapping was performed by focusing on the region surrounding rs710521, and variants were prioritized for further experiments using ENCODE regulatory data. The enhancer activity of the identified region was evaluated using dual-luciferase assays. CRISPR/Cas9-mediated deletion of the enhancer region was performed and the effect of this deletion on cell proliferation and gene expression levels was evaluated using CellTiter-Glo and RT-qPCR, respectively. RESULTS: Fine-mapping of the GWAS signal region led to the identification of twenty SNPs that showed a stronger association with bladder cancer risk than rs710521. Using publicly available data on regulatory elements and sequences, an enhancer region containing the bladder cancer risk variants was identified. Through reporter assays, we found that the presence of the enhancer region significantly increased ΔNTP63 promoter activity in bladder cancer-derived cell lines. CRISPR/Cas9-mediated deletion of the enhancer region reduced the viability of bladder cancer cells by decreasing the expression of ΔNTP63 and p63 target genes. CONCLUSIONS: Taken together, our data show that bladder cancer risk-associated variants on chromosome 3q28 are located in an active enhancer region. Further characterization of the allele-specific activity of the identified enhancer and its target genes may lead to the identification of novel signaling pathways involved in bladder carcinogenesis.


Asunto(s)
Variación Genética/genética , Procolágeno-Prolina Dioxigenasa/genética , Factores de Transcripción/genética , Proteínas Supresoras de Tumor/genética , Neoplasias de la Vejiga Urinaria/genética , Línea Celular , Supervivencia Celular/genética , Supervivencia Celular/fisiología , Predisposición Genética a la Enfermedad/genética , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Polimorfismo de Nucleótido Simple/genética
7.
Opt Express ; 26(4): 4942-4953, 2018 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-29475337

RESUMEN

In this paper, a theoretical investigation of the performance of a communication scenario where a geostationary-orbit satellite provides radio-frequency broadband access to the users through orthogonal-frequency-division multiplexing technology and has an optical feeder link is presented. The interface between the radio frequency and the optical parts is achieved by using radio-on-fiber technology for optical-electro and electro-optical conversion onboard and no further signal processing is required. The proposed scheme has significant potential, but presents limitations related to the noise. The noise in both forward and reverse links is described, and the system performance for an example scenario with 1280 MHz bandwidth for QPSK, 16QAM, and 64QAM subcarrier modulation is estimated. The obtained results show that under certain conditions regarding link budget and components choice, the proposed solution is feasible.

8.
Sci Rep ; 7(1): 11402, 2017 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-28900252

RESUMEN

Cancer-specific metabolic alterations are of high interest as therapeutic targets. These alterations vary between tumor types, and to employ metabolic targeting to its fullest potential there is a need for robust methods that identify candidate targetable metabolic pathways in individual cancers. Currently, such methods include 13C-tracing studies and mass spectrometry/ magnetic resonance spectroscopic imaging. Due to high cost and complexity, such studies are restricted to a research setting. We here present the validation of a novel technique of metabolic profiling, based on multiplex targeted next generation sequencing of RNA with single molecule molecular inversion probes (smMIPs), designed to measure activity of and mutations in genes that encode metabolic enzymes. We here profiled an isogenic pair of cell lines, differing in expression of the Von Hippel Lindau protein, an important regulator of hypoxia-inducible genes. We show that smMIP-profiling provides relevant information on active metabolic pathways. Because smMIP-based targeted RNAseq is cost-effective and can be applied in a medium high-throughput setting (200 samples can be profiled simultaneously in one next generation sequencing run) it is a highly interesting approach for profiling of the activity of genes of interest, including those regulating metabolism, in a routine patient care setting.


Asunto(s)
Metabolismo Energético/genética , Perfilación de la Expresión Génica , Transcriptoma , Biología Computacional/métodos , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica , Biblioteca de Genes , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Polimorfismo de Nucleótido Simple , Reproducibilidad de los Resultados
9.
Opt Express ; 24(11): 12254-66, 2016 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-27410141

RESUMEN

Quantum communication, and more specifically Quantum Key Distribution (QKD), enables the transmission of information in a theoretically secure way, guaranteed by the laws of quantum physics. Although fiber-based QKD has been readily available since several years ago, a global quantum communication network will require the development of space links, which remains to be demonstrated. NICT launched a LEO satellite in 2014 carrying a lasercom terminal (SOTA), designed for in-orbit technological demonstrations. In this paper, we present the results of the campaign to measure the polarization characteristics of the SOTA laser sources after propagating from LEO to ground. The most-widely used property for encoding information in free-space QKD is the polarization, and especially the linear polarization. Therefore, studying its behavior in a realistic link is a fundamental step for proving the feasibility of space quantum communications. The results of the polarization preservation of two highly-polarized lasers are presented here, including the first-time measurement of a linearly-polarized source at λ = 976 nm and a circularly-polarized source at λ = 1549 nm from space using a realistic QKD-like receiver, installed in the Optical Ground Station at the NICT Headquarters, in Tokyo, Japan.

10.
Brain Cogn ; 110: 102-111, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27117045

RESUMEN

The primary objective of this study was to examine the effects of aerobic exercise on executive function, specifically inhibitory control, and the transfer to self-control in the dietary domain. It was hypothesized that exercise would enhance inhibitory control, and that this enhancement would facilitate self-control in a laboratory taste test paradigm. Using a crossover design, 51 participants completed counterbalanced sessions of both moderate exercise (experimental condition) and minimal effort walking (control condition) using a treadmill; the intersession interval was 7days. Prior to each exercise bout participants completed a Stroop task. Following each bout participants completed a second Stoop task, as well as a bogus taste test involving three appetitive calorie dense snack foods and two control foods; the amount of each food type consumed during the taste test was covertly measured. Results revealed that moderate exercise significantly improved performance on the Stroop task, and also reduced food consumption during the taste test for appetitive calorie dense snack foods; there was no exercise effect on control food consumption. Exercise-induced gains in Stroop performance mediated the effects of moderate exercise on appetitive snack food consumption. Together these findings provide evidence that a bout of a moderate aerobic exercise can enhance inhibitory control, and support for cross-domain transfer effects to dietary self-control.


Asunto(s)
Apetito/fisiología , Función Ejecutiva/fisiología , Terapia por Ejercicio/métodos , Conducta Alimentaria/fisiología , Inhibición Psicológica , Autocontrol , Bocadillos/psicología , Transferencia de Experiencia en Psicología/fisiología , Adolescente , Adulto , Femenino , Humanos , Adulto Joven
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