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1.
Sensors (Basel) ; 22(2)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35062581

RESUMO

This paper presents a novel passive Schottky-diode frequency doubler equipped with an on-off keying (OOK) modulation port to be used in harmonic transponders for both identification and sensing applications. The amplitude modulation of the second-harmonic output signal is achieved by driving a low-frequency MOSFET, which modifies the dc impedance termination of the doubler. Since the modulation signal is applied to the gate port of the transistor, no static current is drained. A proof-of-concept prototype was manufactured and tested, operating at 1.04 GHz. An on/off ratio of 23 dB was observed in the conversion loss of the doubler for an available input power of -10 dBm. The modulation port of the circuit was excited with a square wave (fm up to 15 MHz), and the measured sidebands in the spectrum featured a good agreement with the theory. Then, the doubler was connected to a harmonic antenna system and tested in a wireless experiment for fm up to 1 MHz, showing an excellent performance. Finally, an experiment was conducted where the output signal of the doubler was modulated by a reed switch used to measure the rotational speed of an electrical motor. This work opens the door to a new class of frequency doublers, suitable for ultra low-power harmonic transponders for identification and sensing applications.

2.
Sensors (Basel) ; 22(11)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35684772

RESUMO

Internet of Things applications based on backscatter radio principles have appeared to address the limitations of high cost and high power consumption. While radio-frequency identification (RFID) sensor nodes are among the most commonly utilized state-of-the-art technologies, their range for passive implementations is typically short and well below 10 m being impractical for "rugged" applications where approaching the tag at such proximity, is not convenient or safe. In this work, we propose a long-range "zero interception" ambient backscatter (LoRAB) communication system relying on low power sensor (tag) deployments. Without employing a dedicated radio transmission, our technology enables the "zero interception" communication of the tags with portable receivers over hundreds of meters. This enables low-cost and low-power communications across a wide range of missions by using chirp spread spectrum (CSS) modulation on ambient FM signals. A laboratory prototype exploiting commercial components (laptops, DAQ, software-defined radios (SDR) platform) have demonstrated the potential by achieving 130 m tag-to-reader distance for a low bit rate of 88 bps with the modulator current consumption at around 103 nA.

3.
Proc Natl Acad Sci U S A ; 115(52): 13210-13215, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30545917

RESUMO

The tremendous increase in the number of components in typical electrical and communication modules requires low-cost, flexible and multifunctional sensing, energy harvesting, and communication modules that can readily reconfigure, depending on changes in their environment. Current subtractive manufacturing-based reconfigurable systems offer limited flexibility (limited finite number of discrete reconfiguration states) and have high fabrication cost and time requirements. Thus, this paper introduces an approach to solve the problem by combining additive manufacturing and origami principles to realize tunable electrical components that can be reconfigured over continuous-state ranges from folded (compact) to unfolded (large surface) configurations. Special "bridge-like" structures are introduced along the traces that increase their flexibility, thereby avoiding breakage during folding. These techniques allow creating truly flexible conductive traces that can maintain high conductivity even for large bending angles, further enhancing the states of reconfigurability. To demonstrate the idea, a Miura-Ori pattern is used to fabricate spatial filters-frequency-selective surfaces (FSSs) with dipole resonant elements placed along the fold lines. The electrical length of the dipole elements in these structures changes when the Miura-Ori is folded, which facilitates tunable frequency response for the proposed shape-reconfigurable FSS structure. Higher-order spatial filters are realized by creating multilayer Miura-FSS configurations, which further increase the overall bandwidth of the structure. Such multilayer Miura-FSS structures feature the unprecedented capability of on-the-fly reconfigurability to different specifications (multiple bands, broadband/narrowband bandwidth, wide angle of incidence rejection), requiring neither specialized substrates nor highly complex electronics, holding frames, or fabrication processes.

4.
Sensors (Basel) ; 21(10)2021 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-34065618

RESUMO

A triple-band single-layer rectenna for outdoor RF energy applications is introduced in this paper. The proposed rectenna operates in the frequency bands of LoRa, GSM-1800, and UMTS-2100 networks. To obtain a triple-band operation, a modified E-shaped patch antenna is used. The receiving module (antenna) of the rectenna system is optimized in terms of its reflection coefficient to match the RF-to-DC rectifier. The final geometry of the proposed antenna is derived by the application of the Moth Search Algorithm and a commercial electromagnetic solver. The impedance matching network of the proposed system is obtained based on a three-step process, including the minimization of the reflection coefficient versus frequency, as well as the minimization of the reflection coefficient variations and the maximization of the DC output voltage versus RF input power. The proposed RF-to-DC rectifier is designed based on the Greinacher topology. The designed rectenna is fabricated on a single layer of FR-4 substrate. Measured results show that our proposed rectenna can harvest RF energy from outdoor (ambient and dedicated) sources with an efficiency of greater than 52%.

5.
J Immunol ; 200(3): 1124-1132, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29263212

RESUMO

The contribution of the host immune system to the efficacy of new anti-hepatitis C virus (HCV) drugs is unclear. We undertook a longitudinal prospective study of 33 individuals with chronic HCV treated with combination pegylated IFN-α, ribavirin, and telaprevir/boceprevir. We characterized innate and adaptive immune cells to determine whether kinetics of the host response could predict sustained virologic response (SVR). We show that characteristics of the host immune system present before treatment were correlated with successful therapy. Augmentation of adaptive immune responses during therapy was more impressive among those achieving SVR. Most importantly, active memory T cell proliferation before therapy predicted SVR and was associated with the magnitude of the HCV-specific responses at week 12 after treatment start. After therapy initiation, the most important correlate of success was minimal monocyte activation, as predicted by previous in vitro work. In addition, subjects achieving SVR had increasing expression of the transcription factor T-bet, a driver of Th1 differentiation and cytotoxic effector cell maturation. These results show that host immune features present before treatment initiation predict SVR and eventual development of a higher frequency of functional virus-specific cells in blood. Such host characteristics may also be required for successful vaccine-mediated protection.


Assuntos
Antivirais/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Proliferação de Células , Hepacivirus/imunologia , Hepatite C Crônica/tratamento farmacológico , Memória Imunológica/imunologia , Imunidade Adaptativa/imunologia , Anticorpos Antivirais/sangue , Quimioterapia Combinada , Feminino , Hepatite C Crônica/imunologia , Humanos , Imunidade Inata/imunologia , Interferon-alfa/uso terapêutico , Estudos Longitudinais , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/uso terapêutico , Polietilenoglicóis/uso terapêutico , Prolina/análogos & derivados , Prolina/uso terapêutico , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico , Proteínas com Domínio T/biossíntese , Resultado do Tratamento
6.
Sensors (Basel) ; 19(3)2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30754670

RESUMO

In this paper, the far-field energy harvesting system for self-sustainable wireless autonomous sensor application is presented. The proposed autonomous sensor system consists of a wireless power supplier (active antenna) and far-field energy harvesting technology-enabled autonomous battery-less sensors. The wireless power supplier converts solar power to electromagnetic power in order to transfer power to multiple autonomous sensors wirelessly. The autonomous sensors have far-field energy harvesters which convert transmitted RF power to voltage regulated DC power to power-on the sensor system. The hybrid printing technology was chosen to build the autonomous sensors and the wireless power suppliers. Two popular hybrid electronics technologies (direct nano-particle printing and indirect copper thin film printing techniques) are discussed in detail.

7.
Sensors (Basel) ; 19(18)2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31514300

RESUMO

In this paper, we propose a bi-directional loop antenna array using magic cube origami. The proposed antenna array consists of three one-wavelength loop antenna elements with series feeding. Each loop antenna is realized on a single magic cube, and three cubes are connected in series to form the array. The three cubes can be easily folded and unfolded due to being constructed in the form of a magic cube origami. Antenna volume can be minimized for high mobility by folding the array, which radiates a bi-directional pattern with full volume when unfolded. The proposed antenna was designed at 1.39 GHz. When the single antenna is realized on the single cube, the peak gain is 4.03 dBi. The peak gain increased to 5.2 and 5.53 dBi with two and three antennas, respectively. Half-power beam width (HPBW) with three antenna elements decreased to 40° from 360° compared to the HPBW with the single antenna. The proposed antenna performance was assessed numerically and experimentally.

8.
Sensors (Basel) ; 18(6)2018 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-29914190

RESUMO

The detailed design considerations for the printed RFID-based sensor system is presented in this paper. Starting from material selection and metallization method, this paper discusses types of RFID-based sensors (single- & dual-tag sensor topologies), design procedures, and performance evaluation methods for the wireless sensor system. The electrical properties of the paper substrates (cellulose-based and synthetic papers) and the silver nano-particle-based conductive film are thoroughly characterized for RF applications up to 8 GHz. The reported technology could potentially set the foundation for truly “green”, low-cost, scalable wireless topologies for autonomous Internet-of-Things (IoT), bio-monitoring, and “smart skin” applications.

9.
Opt Express ; 23(1): 110-20, 2015 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-25835658

RESUMO

In this paper, we propose a novel microfluidic tunable metamaterial (MM) absorber printed on a paper substrate in silver nanoparticle ink. The metamaterial is designed using a periodic array consisting of square patches. The conductive patterns are inkjet-printed on paper using silver nanoparticle inks. The microfluidic channels are laser-etched on polymethyl methacrylate (PMMA). The conductive patterns on paper and the microfluidic channels on PMMA are bonded by an SU-8 layer that is also inkjet-printed on the conductive patterns. The proposed MM absorber provides frequency-tuning capability for different fluids in the microfluidic channels. We performed full-wave simulations and measurements that confirmed that the resonant frequency decreased from 4.42 GHz to 3.97 GHz after the injection of distilled water into the microfluidic channels. For both empty and water-filled channels, the absorptivity is higher than 90% at horizontal and vertical polarizations.

10.
J Infect Dis ; 209(10): 1602-12, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24325966

RESUMO

BACKGROUND: Interferon α (IFN-α) and ribavirin can induce a sustained virologic response (SVR) in some but not all hepatitis C virus (HCV)-infected patients. The mechanism of effective treatment is unclear. One possibility is that IFN-α differentially improves the functional capacity of classic myeloid dendritic cells (mDCs) by altering expression of surface molecules or cytokines. Others have proposed that antigen-presenting cell activation could be paradoxically detrimental during HCV infection because of the production by monocytes of substances inhibitory or toxic to plasmacytoid dendritic cells. METHODS: We examined responses to in vitro IFN-α treatment of peripheral blood leukocyte samples from a retrospective treatment cohort of nearly 200 HCV-seropositive patients who had undergone antiviral therapy with ribavirin and pegylated IFN. We analyzed the variable responses of antigen-presenting cell subsets to drug. RESULTS: We found that patients achieving SVR were no more likely to have robust mDC activation in response to IFN-α than those who did not achieve SVR. Rather, patients achieving SVR were distinguished by restrained monocyte activation in the presence of IFN-α, a factor that was second in importance only to IL28B genotype in its association with SVR. CONCLUSIONS: These results suggest that interindividual variability in the response of monocytes to IFN-α is an important determinant of treatment success with IFN-α-based regimens.


Assuntos
Antivirais/uso terapêutico , Hepatite C/tratamento farmacológico , Interferon-alfa/uso terapêutico , Monócitos/efeitos dos fármacos , Monócitos/fisiologia , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Células Apresentadoras de Antígenos , Estudos de Casos e Controles , Estudos de Coortes , Células Dendríticas , Feminino , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Ribavirina/administração & dosagem
11.
Am J Public Health ; 104 Suppl 3: S350-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24754616

RESUMO

OBJECTIVES: We compared chronic liver disease (CLD) mortality from 1999 to 2009 between American Indians and Alaska Natives (AI/ANs) and Whites in the United States after improving CLD case ascertainment and AI/AN race classification. METHODS: We defined CLD deaths and causes by comprehensive death certificate-based diagnostic codes. To improve race classification, we linked US mortality data to Indian Health Service enrollment records, and we restricted analyses to Contract Health Service Delivery Areas and to non-Hispanic populations. We calculated CLD death rates (per 100,000) in 6 geographic regions. We then described trends using linear modeling. RESULTS: CLD mortality increased from 1999 to 2009 in AI/AN persons and Whites. Overall, the CLD death rate ratio (RR) of AI/AN individuals to Whites was 3.7 and varied by region. The RR was higher in women (4.7), those aged 25 to 44 years (7.4), persons residing in the Northern Plains (6.4), and persons dying of cirrhosis (4.0) versus hepatocellular carcinoma (2.5), particularly those aged 25 to 44 years (7.7). CONCLUSIONS: AI/AN persons had greater CLD mortality, particularly from premature cirrhosis, than Whites, with variable mortality by region. Comprehensive prevention and care strategies are urgently needed to stem the CLD epidemic among AI/AN individuals.


Assuntos
Indígenas Norte-Americanos/estatística & dados numéricos , Inuíte/estatística & dados numéricos , Hepatopatias/etnologia , Hepatopatias/mortalidade , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Alaska/epidemiologia , Causas de Morte , Doença Crônica , Atestado de Óbito , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distribuição por Sexo , Estados Unidos/epidemiologia , População Branca/estatística & dados numéricos
12.
Dig Dis Sci ; 59(12): 3043-52, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25102983

RESUMO

BACKGROUND: In 2011, the FDA approved telaprevir (TVR) and boceprevir (BOC) for use with pegylated interferon and ribavirin to treat hepatitis C virus (HCV) genotype 1. We aimed to evaluate the real-world application, tolerability, and effectiveness of TVR- and BOC-based HCV treatment in a large integrated care setting. METHODS: We utilized Northern California Kaiser Permanente Medical Care Program (KPNC) electronic databases and medical records to study the experience of all KPNC patients who initiated TVR or BOC from June 2011 to March 2012. RESULTS: Compared with the pool of 5,194 treatment-eligible patients, the 352 treatment initiators were more likely to be cirrhotic (24 vs. 10%, p < 0.001) and treatment-experienced (44 vs. 22%, p < 0.001). Among the treatment initiators, 211 received TVR and 141 BOC. Overall, 31% discontinued treatment prematurely; 16% of patients stopped treatment early because of side effects. One patient with cirrhosis died of sepsis during treatment. Premature discontinuation was highest among TVR-treated cirrhotic patients (58%). Sustained virologic response (SVR) was achieved in 55% overall and was similar comparing the TVR (56%)- and BOC (53%)-treated groups. The only independent predictors of treatment failure were cirrhosis at baseline [odds ratio (OR) for SVR 0.44, p = 0.004] and prior partial or null response (OR for SVR 0.57, p = 0.02). CONCLUSIONS: In the initial application of TVR and BOC, patients with cirrhosis and prior treatment failure were prioritized for treatment. In this real-world experience, most patients successfully completed a full treatment course. However, side effect-related premature discontinuations were common, and SVR rates were lower than reported in clinical trials.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/uso terapêutico , Prolina/análogos & derivados , Adulto , Idoso , Antivirais/administração & dosagem , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/genética , Humanos , Interferon-alfa/administração & dosagem , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/administração & dosagem , Prolina/administração & dosagem , Prolina/uso terapêutico , RNA Viral/genética , Estudos Retrospectivos , Ribavirina/administração & dosagem , Ribavirina/uso terapêutico , Adulto Jovem
13.
Dig Dis Sci ; 59(9): 2100-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24728968

RESUMO

BACKGROUND: Few population-based studies have described characteristics and management of patients with chronic hepatitis B (CHB) in the USA. METHODS: We retrospectively studied adults with CHB in the Northern California Kaiser Permanente Medical Care Program (KPNC) from July 2009 to December 2010 (n = 12,016). Laboratory tests, treatment patterns, and hepatocellular carcinoma (HCC) surveillance were ascertained during a "recent" 18-month study window (July 2009-December 2010), or as "ever" based on records dating to 1995. RESULTS: The mean age was 49 years; 51 % were men, 83 % Asian, and 87 % KPNC members >5 years. Overall, 51 % had ≥ 1 liver-related visit, 14 % with gastroenterology or infectious disease specialists, and 37 % with primary care providers (PCP) only. Less than 40 % of patients had both hepatitis B virus (HBV) DNA and ALT testing conducted recently, while 56 % of eligible patients had received HCC surveillance. Recent laboratory testing and HCC surveillance were more frequent in patients seen by a specialist versus PCP only (90 vs. 47 % and 92 vs. 73 %, respectively, p values <0.001). During the study period, 1,649 (14 %) received HBV treatment, while 5 % of untreated patients had evidence of treatment eligibility. Among 599 patients newly initiated on HBV therapy, 76 % had guideline-based indications for treatment. CONCLUSIONS: Most patients initiated on HBV treatment met eligibility, and very few patients with evidence of needing treatment were left untreated. However, monitoring of ALT and HBV DNA levels, as well as HCC surveillance, were not frequent, underestimating the proportion of patients that warranted HBV therapy. Viral monitoring and cancer surveillance are therefore important targets for improving the scope of CHB care in the community setting.


Assuntos
Carcinoma Hepatocelular/diagnóstico , DNA Viral/sangue , Hepatite B Crônica/sangue , Hepatite B Crônica/tratamento farmacológico , Neoplasias Hepáticas/diagnóstico , Adolescente , Adulto , Idoso , Alanina Transaminase/sangue , Antivirais/uso terapêutico , California , Carcinoma Hepatocelular/sangue , Prestação Integrada de Cuidados de Saúde , Feminino , Gastroenterologia/estatística & dados numéricos , Fidelidade a Diretrizes , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Humanos , Infectologia/estatística & dados numéricos , Neoplasias Hepáticas/sangue , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Guias de Prática Clínica como Assunto , Padrões de Prática Médica , Atenção Primária à Saúde/estatística & dados numéricos , Estudos Retrospectivos , Conduta Expectante , Adulto Jovem , alfa-Fetoproteínas/metabolismo
14.
Sci Rep ; 14(1): 17787, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090193

RESUMO

Fluid sensing has been an important but missing part of the massive Internet-of-Things sensor networks due to challenges including excessive manufacturing time/cost, finite wireless interrogation range, limited immunity to ambient clutter, and excessive required power for autonomous microfluidics operability. Here, we proposed an additive manufacturing flexible system as a solution to those challenges while enabling fluid analysis from controlled labs to virtually everywhere. Energy harvesting provides all required power for the actuation of the micro-pump enabling battery-less liquid sample acquisition. Energy sources including ultra-high-frequency radio frequency identification and hand-held devices like two-way talk radio are harvested simultaneously to support energy requirements for periodic monitoring every 6.6 min and on-demand monitoring within 4.63 s. Backscattering topologies are used to significantly extend the reading range while increasing the immunity to interferences and reducing the cost to the reader. A new additive manufacturing process is proposed to reduce fabrication time and cost while enabling massive scalability of flexible microfluidics. The good flexibility makes the system suitable for working toward future wearable applications. Prototypes of a sweat sensing system are demonstrated and successfully interrogated at 3 m with more than 15 dB signal-to-noise ratio using only a 14 dBm transmitter equivalent isotropic radiated power.

15.
Sci Rep ; 14(1): 10002, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693170

RESUMO

With the current development of the 5G infrastructure, there presents a unique opportunity for the deployment of battery-less mmWave reflect-array-based sensors. These fully-passive devices benefit from having a larger detectability than alternative battery-less solutions to create self-monitoring megastructures. The presented 'smart' skin sensor uses a Van-Atta array design enabling ubiquitous local strain monitoring for the structural health monitoring of composite materials featuring wide interrogation angles. Proof-of-concept prototypes of these 'smart' skin millimeter-wave identification tags, that can be mounted on or embedded within common materials used in wind turbine blades, present a highly-detectable radar cross-section of - 33.75 dBsm and - 35.00 dBsm for mounted and embedded sensors respectively. Both sensors display a minimum resolution of 202 µ -strain even at 40 ∘ off-axis enabling interrogation of the fully-passive sensor at oblique angles of incidence. When interrogated from a proof-of-concept reader, the fully-passive, sticker-like mmID enables local strain monitoring of both carbon fiber and glass fiber composite materials. The sensors display a repeatable and recoverable response over 0-3000 µ -strain and a sensitivity of 7.55 kHz/ µ -strain and 7.92 kHz/ µ -strain for mounted and embedded sensors, respectively. Thus, the presented 5G-enabled battery-less sensor presents massive potential for the development of ubiquitous Digital Twinning of composite materials in future smart cities architectures.

16.
Nat Genet ; 6(2): 157-62, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8162070

RESUMO

Cervical carcinoma is now known to be associated with human papillomaviruses (HPV), but the evidence for a link with specific HLA loci is controversial. The role of genetic variation at the HLA class II loci and among HPV types in cervical carcinoma was investigated by PCR DNA amplification and oligonucleotide probe typing of paraffin-embedded invasive cervical cancer tissue from Hispanic patients and of cervical swabs from Hispanic controls. Certain HLA class II haplotypes (such as DRB1*1501-DQB1*0602) were associated significantly, while DR13 haplotypes were negatively associated with cervical carcinoma. These associations are HPV16-type specific. These results suggest that specific HLA class II haplotypes may influence the immune response to specific HPV-encoded epitopes and affect the risk of cervical neoplasia.


Assuntos
Adenocarcinoma/imunologia , Carcinoma de Células Escamosas/imunologia , Antígenos HLA-DQ/análise , Antígenos HLA-DR/análise , Papillomaviridae/fisiologia , Neoplasias do Colo do Útero/imunologia , Adenocarcinoma/epidemiologia , Adenocarcinoma/virologia , Carcinoma de Células Escamosas/virologia , Estudos de Casos e Controles , Suscetibilidade a Doenças , Feminino , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Haplótipos , Hispânico ou Latino , Teste de Histocompatibilidade , Humanos , Razão de Chances , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Reação em Cadeia da Polimerase , Sudoeste dos Estados Unidos , Infecções Tumorais por Vírus/imunologia , Infecções Tumorais por Vírus/virologia , Neoplasias do Colo do Útero/virologia
17.
Sci Rep ; 13(1): 21736, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066257

RESUMO

Wireless sensor networks for environmental monitoring are a key feature in developing the Internet of Things. Although there has been much research in developing components for wireless sensing nodes, advances in creating fully integrated sensing nodes is limited. Furthermore, because most sensing nodes that have been developed are intended to perform a fixed task, each new effort to design an integrated sensing node with different functionality must start from scratch. Here we introduce a broadly applicable platform for the development and production of fully integrated wireless sensing nodes. The platform is an additively manufactured cube that has different subsystems occupying separate faces of the 3D structure. While both additively manufactured sensors and cube-shaped wireless sensing nodes have been previously reported, these two approaches have yet to be combined. A key technology that enables this is the use of additively manufactured, nonplanar bent microstrips. This realization offers a "plug-and-play" approach to sensor node design, as the subsystems are considered modular and can be swapped to alter the function of the device. Implementing this concept enables the rapid development and deployment of wireless sensor networks.

18.
Sci Rep ; 13(1): 12515, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532806

RESUMO

This paper thoroughly investigates material characterization, reliability evaluation, fabrication, and assembly processes of additively manufactured flexible packaging and reconfigurable on-package antenna arrays for next-generation 5G/mmWave wearable and conformal applications. The objective is to bridge the technology gap in current Flexible Hybrid Electronics (FHE) designs at mmWave frequencies and address the challenges of establishing future design standards for additively manufactured flexible packages and System-on-Package (SoP) integrated modules. Multiple 3D printed flexible materials have been characterized for their electrical and mechanical properties over the 5G/mmW frequency band (26-40 GHz), and the inkjet printed interconnects on 3D printed Polypropylene (PP) substrates demonstrated excellent electrical and mechanical performance during a 10,000-time cyclic bending test over typical wearable flexible radii down to 1 inch. A proof-of-concept flexible on-package phased array with an integrated microfluidic cooling channel on 3D printed substrates was fabricated and measured, demonstrating [Formula: see text] beam steering capability with efficient cooling. The proposed reconfigurable design and low-temperature fabrication approach using additive manufacturing can be widely applied to next-generation highly-complex on-demand FHE, flexible multi-chip-module integration, and on-package phased-array modules for 5G/mmWave wearable and conformal smart skin, digital twin and massive MIMO applications.

19.
J Med Virol ; 84(11): 1744-50, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22997077

RESUMO

Hepatitis C virus (HCV) genotypes influence response to therapy, and recently approved direct-acting antivirals are genotype-specific. Genotype distribution information can help to guide antiviral development and elucidate infection patterns. HCV genotype distributions were studied in a diverse cross-section of patients in the Northern California Kaiser Permanente health plan. Associations between genotype and race/ethnicity, age, and sex were assessed with multivariate logistic regression models. The 10,256 patients studied were median age 56 years, 62% male, 55% White non-Hispanic. Overall, 70% were genotype 1, 16% genotype 2, 12% genotype 3, 1% genotype 4, <1% genotype 5, and 1% genotype 6. Blacks (OR 4.5 [3.8-5.5]) and Asians (OR 1.2 [1.0-1.4]) were more likely to have genotype 1 than 2/3 versus non-Hispanic Whites. Women less likely had genotype 1 versus 2/3 than did men (OR 0.86 [0.78-0.94]). Versus non-Hispanic Whites, Asians (OR 0.38 [0.31-0.46]) and Blacks (OR 0.73 [0.63-0.84]) were less likely genotype1a than 1b; Hispanics (OR 1.3 [1.1-1.5]) and Native Americans (OR 1.9 [1.2-2.8]) more likely had genotype 1a than 1b. Patients age ≥65 years less likely had genotype 1a than 1b versus those age 45-64 (OR 0.34 [0.29-0.41]). The predominance of genotype 1 among all groups studied reinforces the need for new therapies targeting this genotype. Racial/ethnic variations in HCV genotype and subtype distribution must be considered in formulating new agents and novel strategies to successfully treat the diversity of hepatitis C patients.


Assuntos
Hepacivirus/classificação , Hepacivirus/genética , Hepatite C/epidemiologia , Hepatite C/virologia , Adulto , Distribuição por Idade , Idoso , California/epidemiologia , Estudos Transversais , Etnicidade , Feminino , Genótipo , Hepacivirus/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Distribuição por Sexo
20.
Inorg Chem ; 51(22): 12248-59, 2012 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-23110634

RESUMO

The reaction of copper(I) iodide with 6-n-propylthiouracil (ptu) in the presence or absence of the triphenylphosphine (tpp) or tri(p-tolyl)phosphine (tptp) in a 1:1:2 molar ratio forms the mixed ligand Cu(I) complex with formula [CuI(ptu)2](toluene) (1), [CuI(tpp)2(ptu)] (2), and [CuI(tptp)2(ptu)] (3). The complexes have been characterized by FT-IR, (1)H NMR, UV-vis, spectroscopic techniques, and single crystal X-ray crystallography. Two sulfur atoms from two ptu ligands and one iodide form a trigonal geometry around the metal center in 1. Intramolecular interactions through hydrogen bonds lead to a bend ribbon polymeric supramolecular architecture with zigzag conformation. Two phosphorus atoms from two arylphosphines, one sulfur atom, and one iodide anion form a tetrahedron around the copper ion in case of 2 and 3. Intramolecular hydrogen bonding interactions lead to dimerization. Complexes 1-3 and the already known ones with formulas, [(tpSb)2Cu(µ2-I)2Cu(tpSb)2] (4) (tbSb = triphenylstibine), [(tpp)Cu(µ2-I)2Cu(tpp)2] (5), [(tpp)Cu(µ2-Cl)2Cu(tpp)2] (6), [CuCl(tpp)3·(CH3CN)] (7), and [AuCl(tpp)] (8), were used to study their catalytic activity on the intermolecular cycloaddition of iodonium ylides toward benzo[b]furans formation. The results show that both the metal and the ligand type affect the catalytic affinity of the complexes. The highest yield of benzo[b]furan was derived when complexes 2, 3, and 4 were used as catalysts. The mechanism of the Cu(I)-catalyzed and uncatalyzed intramolecular cycloaddition of iodonium ylide has been also thoroughly explored by means of ab initio electronic structure calculation methods, and the results are compared with the experimental ones.


Assuntos
Benzofuranos/síntese química , Iodo/química , Compostos Organometálicos/química , Preparações Farmacêuticas/química , Antitireóideos/química , Benzofuranos/química , Catálise , Cobre/química , Cristalografia por Raios X , Ciclização , Iodetos/química , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Teoria Quântica , Tioureia/análogos & derivados , Tioureia/química
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