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1.
Sensors (Basel) ; 20(18)2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32937798

RESUMO

This paper presents a system of sensors used in flash flood prediction that offers critical real-time information used to provide early warnings that can provide the minutes needed for persons to evacuate before imminent events. Flooding is one of the most serious natural disasters humans confront in terms of loss of life and results in long-term effects, which often have severely adverse social consequences. However, flash floods are potentially more dangerous to life because there is often little or no forewarning of the impending disaster. The Emergency Water Information Network (EWIN) offers a solution that integrates an early warning system, notifications, and real-time monitoring of flash flood risks. The platform has been implemented in Colima, Mexico covering the Colima and Villa de Alvarez metropolitan area. This platform consists of eight fixed riverside hydrological monitoring stations, eight meteorological stations, nomadic mobile monitoring stations called "drifters" used in the flow, and a sniffer with data muling capability. The results show that this platform effectively compiles and forwards information to decision-makers, government officials, and the general public, potentially providing valuable minutes for people to evacuate dangerous areas.

2.
Sensors (Basel) ; 19(1)2019 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-30609726

RESUMO

Flooding is one of the most frequent and costly natural disasters affecting mankind. However, implementing Internet of Things (IoT) technology to monitor river behavior may help mitigate or prevent future disasters. This article outlines the hardware development of an IoT system (RiverCore) and defines an application scenario in a specific hydrological region of the state of Colima (Mexico), highlighting the characteristics of data acquisition and data processing used. Both fixed position and moving drifter node systems are described along with web-based data acquisition platform developments integrated with IoT techniques to retrieve data through 3G cellular networks. The developed architecture uses the Message Queuing Telemetry Transport (MQTT) protocol, along with encryption and security mechanisms, to send real-time data packages from fixed nodes to a server that stores retrieved data in a non-relational database. From this, data can be accessed and displayed through different customizable queries and graphical representations, allowing future use in flood analysis and prediction systems. All of these features are presented along with graphical evidence of the deployment of the different devices and of several cellular communication and on-site data acquisition tests.


Assuntos
Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Inundações/prevenção & controle , Hidrologia/estatística & dados numéricos , Internet/instrumentação , Rios , Telemetria/instrumentação , Computação em Nuvem , Inundações/estatística & dados numéricos , Armazenamento e Recuperação da Informação , México , Aplicativos Móveis
3.
Sensors (Basel) ; 17(1)2017 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-28106832

RESUMO

The number of elderly and chronically ill patients has grown significantly over the past few decades as life expectancy has increased worldwide, leading to increased demands on the health care system and significantly taxing traditional health care practices. Consequently, there is an urgent need to use technology to innovate and more constantly and intensely monitor, report and analyze critical patient physiological parameters beyond conventional clinical settings in a more efficient and cost effective manner. This paper presents a technological platform called PlaIMoS which consists of wearable sensors, a fixed measurement station, a network infrastructure that employs IEEE 802.15.4 and IEEE 802.11 to transmit data with security mechanisms, a server to analyze all information collected and apps for iOS, Android and Windows 10 mobile operating systems to provide real-time measurements. The developed architecture, designed primarily to record and report electrocardiogram and heart rate data, also monitors parameters associated with chronic respiratory illnesses, including patient blood oxygen saturation and respiration rate, body temperature, fall detection and galvanic resistance.


Assuntos
Atenção à Saúde , Frequência Cardíaca , Monitorização Fisiológica , Oximetria , Respiração , Software
4.
Nat Chem Biol ; 6(4): 291-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20190765

RESUMO

We describe a strategy for comprehending signaling pathways that are active in lung cancer cells and that are targeted by dasatinib using chemical proteomics to identify direct interacting proteins combined with immunoaffinity purification of tyrosine-phosphorylated peptides corresponding to activated tyrosine kinases. We identified nearly 40 different kinase targets of dasatinib. These include SRC-family kinase (SFK) members (LYN, SRC, FYN, LCK and YES), nonreceptor tyrosine kinases (FRK, BRK and ACK) and receptor tyrosine kinases (Ephrin receptors, DDR1 and EGFR). Using quantitative phosphoproteomics, we identified peptides corresponding to autophosphorylation sites of these tyrosine kinases that are inhibited in a concentration-dependent manner by dasatinib. Using drug-resistant gatekeeper mutants, we show that SFKs (particularly SRC and FYN), as well as EGFR, are relevant targets for dasatinib action. The combined mass spectrometry-based approach described here provides a system-level view of dasatinib action in cancer cells and suggests both functional targets and a rationale for combinatorial therapeutic strategies.


Assuntos
Neoplasias Pulmonares/tratamento farmacológico , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Proteômica/métodos , Pirimidinas/farmacologia , Tiazóis/farmacologia , Apoptose , Linhagem Celular Tumoral , Dasatinibe , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Espectrometria de Massas , Peptídeos/química , Peptídeos/metabolismo , Fenótipo , Fosforilação/efeitos dos fármacos , Ligação Proteica , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Pirimidinas/metabolismo , Pirimidinas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Tiazóis/metabolismo , Tiazóis/uso terapêutico
5.
Sensors (Basel) ; 12(6): 8204-17, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22969396

RESUMO

Because battery-powered nodes are required in wireless sensor networks and energy consumption represents an important design consideration, alternate energy sources are needed to provide more effective and optimal function. The main goal of this work is to present an energy harvesting wireless sensor network platform, the Open Wireless Sensor node (WiSe). The design and implementation of the solar powered wireless platform is described including the hardware architecture, firmware, and a POSIX Real-Time Kernel. A sleep and wake up strategy was implemented to prolong the lifetime of the wireless sensor network. This platform was developed as a tool for researchers investigating Wireless sensor network or system integrators.

6.
Sensors (Basel) ; 12(11): 14262-91, 2012 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-23202159

RESUMO

Vehicular Ad Hoc Networks (VANETs) are considered by car manufacturers and the research community as the enabling technology to radically improve the safety, efficiency and comfort of everyday driving. However, before VANET technology can fulfill all its expected potential, several difficulties must be addressed. One key issue arising when working with VANETs is the complexity of the networking protocols compared to those used by traditional infrastructure networks. Therefore, proper design of the routing strategy becomes a main issue for the effective deployment of VANETs. In this paper, a reliable freestanding position-based routing algorithm (FPBR) for highway scenarios is proposed. For this scenario, several important issues such as the high mobility of vehicles and the propagation conditions may affect the performance of the routing strategy. These constraints have only been partially addressed in previous proposals. In contrast, the design approach used for developing FPBR considered the constraints imposed by a highway scenario and implements mechanisms to overcome them. FPBR performance is compared to one of the leading protocols for highway scenarios. Performance metrics show that FPBR yields similar results when considering freespace propagation conditions, and outperforms the leading protocol when considering a realistic highway path loss model.

7.
J Phys Condens Matter ; 23(5): 055502, 2011 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-21406910

RESUMO

We present a theoretical study of the nuclear quadrupole interaction, ν(Q), of (75)As in crystalline and amorphous materials containing sulfur and selenium, and compare them with experiment. We studied a combination of hydrogen-terminated molecular clusters and periodic cells at various levels of quantum chemical theory. The results show clearly that the standard density functional theory (DFT) approximations, LDA and GGA, underestimate the nuclear quadrupole (NQR) interaction systematically, while Hartree-Fock theory overestimates it to an even greater degree. However, various levels of configuration interaction and the B3LYP hybrid exchange-correlation functional, which includes some exact exchange, give very good quantitative agreement for As bonded only to the chalcogen species. As-As bonds require highly converged basis sets. We have performed a systematic study of the effect of local distortions around an arsenic atom on ν(Q) and η. Using a simple, semiclassical model, we have combined our total energy results with our NQR calculations to predict ν(Q) lineshapes for bond angle and bond length distortions. Our predictions for lineshape, including first and second moments, are in excellent agreement with the results of Su et al for a-As(2)S(3), a-As(2)Se(3) and a-AsSe. We offer new insight into the distortions that led to this inhomogeneous broadening. Our results show clearly that, for trivalent arsenic atoms with zero or one arsenic nearest neighbor, symmetric bond stretching is the predominant contributor to the ν(Q) linewidth. However, in the presence of two arsenic nearest neighbors, distortions of the As-As-As apex angle dominates and, in fact, leads to a much larger second moment, in agreement with experiment.

8.
Mol Cancer Ther ; 6(9): 2515-24, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17876048

RESUMO

Activating mutations in the epidermal growth factor receptor (EGFR) selectively activate signal transducers and activators of transcription (STAT) and Akt survival signaling pathways important in lung cancer cell growth and survival. Many kinases, such as EGFR, rely on heat shock protein 90 (Hsp90) chaperone function for conformational maturation and proper function. Histone deacetylase inhibitors (HDACi) have been suggested to regulate signaling protein interactions via modulation of protein chaperone function through Hsp90. For these reasons, we evaluated the effect of a HDACi in lung cancer cells with defined EGFR status. Cell lines with defined EGFR status and sensitivity to EGFR tyrosine kinase inhibitors were exposed to the HDACi LBH589, and the effects on cell survival, proliferation, and downstream signaling were evaluated. LBH589 resulted in increased acetylation of Hsp90 and reduced association of Hsp90 with EGFR, Akt, and STAT3. LBH589 selectively depleted proteins important in signaling cascades in cell lines harboring EGFR kinase mutations, such as EGFR, STAT3, and Akt, and these cells underwent apoptosis following exposure to LBH589. In addition, we found depletion of STAT3-dependent survival proteins, including Bcl-xL, Mcl-1, and Bcl-2. Conversely, LBH589 had little effect on apoptosis in cells not dependent on EGFR for survival, no changes were identified in the expression of EGFR or other survival proteins, and the predominant effect was cell cycle arrest rather than apoptosis. A 10-fold increase in LBH589 was necessary to observe durable depletion of EGFR and Akt in cells not harboring EGFR mutation. Treatment of cells with erlotinib and LBH589 resulted in synergistic effects on lung cancer cells dependent on EGFR for growth and/or survival. Based on these results, LBH589 can acetylate Hsp90, deplete EGFR and other key survival signaling proteins, and trigger apoptosis only in lung cancer cells harboring EGFR mutations. Therefore, EGFR mutation status may be predictive of outcome with LBH589 and possibly other HDACi.


Assuntos
Receptores ErbB/metabolismo , Inibidores de Histona Desacetilases , Neoplasias Pulmonares/tratamento farmacológico , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Immunoblotting , Imunoprecipitação , Indóis , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Panobinostat , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas/efeitos dos fármacos
9.
Cancer Res ; 72(10): 2501-11, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22461510

RESUMO

Driver tyrosine kinase mutations are rare in sarcomas, and patterns of tyrosine phosphorylation are poorly understood. To better understand the signaling pathways active in sarcoma, we examined global tyrosine phosphorylation in sarcoma cell lines and human tumor samples. Anti-phosphotyrosine antibodies were used to purify tyrosine phosphorylated peptides, which were then identified by liquid chromatography and tandem mass spectrometry. The findings were validated with RNA interference, rescue, and small-molecule tyrosine kinase inhibitors. We identified 1,936 unique tyrosine phosphorylated peptides, corresponding to 844 unique phosphotyrosine proteins. In sarcoma cells alone, peptides corresponding to 39 tyrosine kinases were found. Four of 10 cell lines showed dependence on tyrosine kinases for growth and/or survival, including platelet-derived growth factor receptor (PDGFR)α, MET, insulin receptor/insulin-like growth factor receptor signaling, and SRC family kinase signaling. Rhabdomyosarcoma samples showed overexpression of PDGFRα in 13% of examined cases, and sarcomas showed abundant tyrosine phosphorylation and expression of a number of tyrosine phosphorylated tyrosine kinases, including DDR2, EphB4, TYR2, AXL, SRC, LYN, and FAK. Together, our findings suggest that integrating global phosphoproteomics with functional analyses with kinase inhibitors can identify drivers of sarcoma growth and survival.


Assuntos
Proteínas Tirosina Quinases/metabolismo , Proteômica/métodos , Sarcoma/enzimologia , Linhagem Celular Tumoral , Humanos , Fosforilação , Fosfotirosina/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , RNA Interferente Pequeno/farmacologia , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais
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