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1.
J Am Pharm Assoc (2003) ; 62(1): 104-111.e2, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34702646

RESUMEN

BACKGROUND: The Appointment-Based Model (ABM) is a care model that helps community pharmacists streamline their medication dispensing workflow while simultaneously integrating patient care into the medication preparation process through medication synchronization. Implementation of the ABM has varied across community pharmacies. Further studies that identify tailored implementation approaches are needed to support broad adoption of the ABM in practice. OBJECTIVES: (1) To determine facilitators and barriers to ongoing adoption and implementation of the ABM at a small chain of rural independent pharmacies where adoption has stalled and (2) to identify implementation strategies to support further adoption of the ABM at these pharmacies METHODS: This project was an exploratory, mid-implementation study. Semistructured interviews were conducted with pharmacy staff who participated in the ongoing implementation and use of the ABM at the pharmacies. Interviews elicited stakeholder-centered perspectives on (1) experiences with the ABM to date, (2) processes and roles for the ABM, and (3) opinions on how implementation of the ABM could be improved at the pharmacies. Rapid qualitative assessment methodology was used for analysis to identify facilitators and barriers and to select implementation strategies. RESULTS: Thirty-one pharmacy personnel were interviewed: pharmacists (n = 10), pharmacy technicians (n = 7), and fill clerks (n = 14). The research team identified 6 facilitators and 4 barriers to the implementation of the ABM at the pharmacies. Five implementation strategies were selected based on the facilitators and barriers: (1) capture and share local knowledge across pharmacy sites, (2) conduct educational outreach visits, (3) conduct ongoing training, (4) prepare patients to be active participants in the ABM, and (5) organize clinician implementation team meetings. CONCLUSIONS: Development of a stakeholder-driven implementation approach may support further implementation and adoption of the ABM in practice.


Asunto(s)
Servicios Comunitarios de Farmacia , Farmacias , Farmacia , Humanos , Farmacéuticos , Técnicos de Farmacia
2.
Hum Mol Genet ; 24(2): 330-45, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25168387

RESUMEN

Huntington's disease is an autosomal dominant neurodegenerative disorder caused by a CAG expansion mutation in HTT, the gene encoding huntingtin. Evidence from both human genotype-phenotype relationships and mouse model systems suggests that the mutation acts by dysregulating some normal activity of huntingtin. Recent work in the mouse has revealed a role for huntingtin in epigenetic regulation during development. Here, we examine the role of the Drosophila huntingtin ortholog (dhtt) in chromatin regulation in the development of the fly. Although null dhtt mutants display no overt phenotype, we found that dhtt acts as a suppressor of position-effect variegation (PEV), suggesting that it influences chromatin organization. We demonstrate that dhtt affects heterochromatin spreading in a PEV model by modulating histone H3K9 methylation levels at the heterochromatin-euchromatin boundary. To gain mechanistic insights into how dhtt influences chromatin function, we conducted a candidate genetic screen using RNAi lines targeting known PEV modifier genes. We found that dhtt modifies phenotypes caused by knockdown of a number of key epigenetic regulators, including chromatin-associated proteins, histone demethylases (HDMs) and methyltransferases. Notably, dhtt strongly modifies phenotypes resulting from loss of the HDM dLsd1, in both the ovary and wing, and we demonstrate that dhtt appears to act as a facilitator of dLsd1 function in regulating global histone H3K4 methylation levels. These findings suggest that a fundamental aspect of huntingtin function in heterochromatin/euchromatin organization is evolutionarily conserved across phyla.


Asunto(s)
Drosophila/crecimiento & desarrollo , Drosophila/metabolismo , Heterocromatina/metabolismo , Enfermedad de Huntington/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Animales , Drosophila/genética , Proteínas de Drosophila , Femenino , Regulación del Desarrollo de la Expresión Génica , Heterocromatina/genética , Humanos , Proteína Huntingtina , Enfermedad de Huntington/genética , Masculino , Metilación , Proteínas Asociadas a Microtúbulos/genética , Ovario/crecimiento & desarrollo , Ovario/metabolismo , Alas de Animales/crecimiento & desarrollo , Alas de Animales/metabolismo
3.
Opt Express ; 25(4): 4554-4563, 2017 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-28241659

RESUMEN

The Gaussian noise model is used to estimate the performance of three digital nonlinearity compensation (NLC) algorithms in C-band, long-haul, optical fiber transmission, when the span length and NLC bandwidth are independently varied. The algorithms are receiver-side digital backpropagation (DBP), transmitter-side DBP (digital precompensation), and Split NLC (an equal division of DBP between transmitter and receiver). For transmission over 100×100 km spans, the model predicts a 0.2 dB increase in SNR when applying Split NLC (versus DBP) to a single 32 GBd channel (from 0.4 dB to 0.6 dB), monotonically increasing with NLC bandwidth up to 1.6 dB for full-field NLC. The underlying assumptions of this model and the practical considerations for implementation of Split NLC are discussed. This work demonstrates, theoretically, that, regardless of the transmission scenario, it is always beneficial to divide NLC between transmitter and receiver, and identifies the transmission regimes where Split NLC is particularly advantageous.

4.
Opt Lett ; 41(1): 68-71, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26696160

RESUMEN

We demonstrate the use of spectrally shaped amplified spontaneous emission (SS-ASE) noise for wideband channel loading in the investigation of nonlinear transmission limits in wavelength-division multiplexing transmission experiments using Nyquist-spaced channels. The validity of this approach is explored through statistical analysis and experimental transmission of Nyquist-spaced 10 GBaud polarization-division multiplexing (PDM) quadrature phase-shift keying and PDM-16-ary quadrature amplitude modulation (QAM) channels, co-propagated with SS-ASE over single mode fiber. It is shown that this technique, which is simpler to implement than a fully modulated comb of channels, is valid for distances exceeding 240 km for PDM-16QAM with dispersion of 16 ps/nm/km, yields a good agreement with theory, and provides a conservative measure of system performance.

5.
Philos Trans A Math Phys Eng Sci ; 374(2062)2016 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-26809572

RESUMEN

Most of the digital data transmitted are carried by optical fibres, forming the great part of the national and international communication infrastructure. The information-carrying capacity of these networks has increased vastly over the past decades through the introduction of wavelength division multiplexing, advanced modulation formats, digital signal processing and improved optical fibre and amplifier technology. These developments sparked the communication revolution and the growth of the Internet, and have created an illusion of infinite capacity being available. But as the volume of data continues to increase, is there a limit to the capacity of an optical fibre communication channel? The optical fibre channel is nonlinear, and the intensity-dependent Kerr nonlinearity limit has been suggested as a fundamental limit to optical fibre capacity. Current research is focused on whether this is the case, and on linear and nonlinear techniques, both optical and electronic, to understand, unlock and maximize the capacity of optical communications in the nonlinear regime. This paper describes some of them and discusses future prospects for success in the quest for capacity.

6.
PLoS Genet ; 9(11): e1003958, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24278035

RESUMEN

Neurofibromatosis type 1 (NF1), a genetic disease that affects 1 in 3,000, is caused by loss of a large evolutionary conserved protein that serves as a GTPase Activating Protein (GAP) for Ras. Among Drosophila melanogaster Nf1 (dNf1) null mutant phenotypes, learning/memory deficits and reduced overall growth resemble human NF1 symptoms. These and other dNf1 defects are relatively insensitive to manipulations that reduce Ras signaling strength but are suppressed by increasing signaling through the 3'-5' cyclic adenosine monophosphate (cAMP) dependent Protein Kinase A (PKA) pathway, or phenocopied by inhibiting this pathway. However, whether dNf1 affects cAMP/PKA signaling directly or indirectly remains controversial. To shed light on this issue we screened 486 1(st) and 2(nd) chromosome deficiencies that uncover >80% of annotated genes for dominant modifiers of the dNf1 pupal size defect, identifying responsible genes in crosses with mutant alleles or by tissue-specific RNA interference (RNAi) knockdown. Validating the screen, identified suppressors include the previously implicated dAlk tyrosine kinase, its activating ligand jelly belly (jeb), two other genes involved in Ras/ERK signal transduction and several involved in cAMP/PKA signaling. Novel modifiers that implicate synaptic defects in the dNf1 growth deficiency include the intersectin-related synaptic scaffold protein Dap160 and the cholecystokinin receptor-related CCKLR-17D1 drosulfakinin receptor. Providing mechanistic clues, we show that dAlk, jeb and CCKLR-17D1 are among mutants that also suppress a recently identified dNf1 neuromuscular junction (NMJ) overgrowth phenotype and that manipulations that increase cAMP/PKA signaling in adipokinetic hormone (AKH)-producing cells at the base of the neuroendocrine ring gland restore the dNf1 growth deficiency. Finally, supporting our previous contention that ALK might be a therapeutic target in NF1, we report that human ALK is expressed in cells that give rise to NF1 tumors and that NF1 regulated ALK/RAS/ERK signaling appears conserved in man.


Asunto(s)
Drosophila melanogaster/genética , Trastornos de la Memoria/genética , Neurofibromatosis 1/genética , Quinasa de Linfoma Anaplásico , Animales , AMP Cíclico/genética , Proteínas Quinasas Dependientes de AMP Cíclico/genética , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Humanos , Trastornos de la Memoria/patología , Mutación , Neurofibromatosis 1/metabolismo , Neurofibromatosis 1/fisiopatología , Unión Neuromuscular/genética , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Transducción de Señal/genética , Proteínas Activadoras de ras GTPasa/genética , Proteínas Activadoras de ras GTPasa/metabolismo
7.
Opt Lett ; 40(13): 3025-8, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-26125358

RESUMEN

Transmission of a net 467-Gb/s PDM-16QAM Nyquist-spaced superchannel is reported with an intra-superchannel net spectral efficiency (SE) of 6.6 (b/s)/Hz, over 364-km SMF-28 ULL ultra-low loss optical fiber, enabled by bi-directional second-order Raman amplification and digital nonlinearity compensation. Multi-channel digital back-propagation (MC-DBP) was applied to compensate for nonlinear interference; an improvement of 2 dB in Q(2) factor was achieved when 70-GHz DBP bandwidth was applied, allowing an increase in span length of 37 km.

8.
Burns ; 50(2): 424-432, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38087659

RESUMEN

BACKGROUND: StrataGraft® (allogeneic cultured keratinocytes and dermal fibroblasts in murine collagen-dsat) is an FDA-approved viable bioengineered allogeneic cellularized construct for adult patients with deep partial-thickness burns requiring surgery. We characterized the structural and functional properties of StrataGraft to improve product understanding by evaluating extracellular matrix (ECM) molecule distribution and secreted protein factor expression in vitro. METHODS: ECM protein expression was determined using indirect immunofluorescence on construct cross sections using commercial antibodies against collagen III, IV, VI, laminin-332, and decorin. Human collagen I expression was verified by enzyme-linked immunosorbent assay (ELISA) for collagen I C-terminal propeptide. Soluble protein factor secretion was quantified by multiplex biomarker assays and singleplex ELISA in conditioned media from meshed constructs. RESULTS: StrataGraft cellular components produced collagen I, collagen III, collagen VI, and decorin in patterns indicating an organized ECM. Distributions of collagen IV and laminin-332 indicated formation of basement membranes and dermal-epidermal junctions. Soluble protein factors were observed in the pg/cm2/h range from 1 h to the experiment end at 168 h. CONCLUSIONS: The organization of the ECM proteins was like human skin and the viable cellular components provided sustained secretion of soluble wound healing factors, making StrataGraft an attractive option for treating severe burns.


Asunto(s)
Quemaduras , Trasplante de Células Madre Hematopoyéticas , Adulto , Humanos , Animales , Ratones , Proteínas de la Matriz Extracelular , Decorina , Quemaduras/terapia , Cicatrización de Heridas , Matriz Extracelular , Colágeno Tipo I , Kalinina , Fibroblastos
9.
Opt Lett ; 38(22): 4797-800, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24322135

RESUMEN

The authors report on the downlink performance of a 10 Gb/s long-reach and ultra-dense wavelength-division multiplexed passive optical network, based on a multicarrier transmitter realized by using an externally injected gain-switched distributed-feedback laser diode. Each of the comb channels, spaced by 10 GHz, is modulated with a 3 Gbaud dual polarization quadrature phase shift keying signal that included a 20% overhead for forward error correction. Frequency selectivity and enhanced receiver sensitivity is achieved by employing a digital coherent receiver to receive the signal. Experimental results achieved in a back-to-back and 100 km transmission scenarios show an excellent worst case receiver sensitivity of -44 dBm.

10.
ACS Med Chem Lett ; 14(12): 1631-1639, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38116426

RESUMEN

Redirecting E3 ligases to neo-substrates, leading to their proteasomal disassembly, known as targeted protein degradation (TPD), has emerged as a promising alternative to traditional, occupancy-driven pharmacology. Although the field has expanded tremendously over the past years, the choice of E3 ligases remains limited, with an almost exclusive focus on CRBN and VHL. Here, we report the discovery of novel ligands to the PRY-SPRY domain of TRIM58, a RING ligase that is specifically expressed in erythroid precursor cells. A DSF screen, followed by validation using additional biophysical methods, led to the identification of TRIM58 ligand TRIM-473. A basic SAR around the chemotype was established by utilizing a competitive binding assay employing a short FP peptide probe derived from an endogenous TRIM58 substrate. The X-ray co-crystal structure of TRIM58 in complex with TRIM-473 gave insights into the binding mode and potential exit vectors for bifunctional degrader design.

11.
Res Social Adm Pharm ; 18(4): 2569-2578, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34083133

RESUMEN

INTRODUCTION: Depression and pain are common, disabling, mutually exacerbating conditions. Many patients living with these conditions present to community pharmacies on a regular schedule to purchase both prescribed and over-the-counter medications. Community-pharmacy based programs have been developed to improve depression and pain outcomes. METHODS: The PRISMA guidelines were utilized to answer the following question: In patients with depression and/or pain, what is the effect of the existing community pharmacy programs on depression and/or pain outcomes. Queried databases included Pubmed, EMBASE, and PsychINFO. DistillerSR was used to organize the screening, abstraction, and review of data. All potential articles were evaluated by two authors, and conflicts were discussed to achieve resolution. In addition to primary outcomes, sources of potential bias and quality indicators were abstracted for every article. RESULTS: Three thousand nine hundred and twenty articles were reviewed, and 13 studies met eligibility criteria (n = 7 for depression; n = 6 for pain). Most studies demonstrated improvement in measures of depression or pain. However, compared to usual care or other control conditions, most of the depression and pain-specific interventions did not provide additional symptomatic benefit. The community pharmacy-based interventions were superior for other outcomes including medication adherence, reducing stigma, improvement in self-efficacy, and improvement in general management of disease. CONCLUSION: Community pharmacies may be uniquely positioned to deliver interventions that improve outcomes associated with successful depression and pain treatment outcomes. However, the benefits of published community pharmacy-based treatments for actually improving depression and pain severity has not yet been established. Innovative interventions and additional research may be needed to achieve clinical success for pharmacy interventions for depression and pain.


Asunto(s)
Farmacias , Depresión/tratamiento farmacológico , Humanos , Cumplimiento de la Medicación , Dolor/tratamiento farmacológico , Medición de Resultados Informados por el Paciente
12.
Opt Express ; 19(26): B313-22, 2011 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-22274036

RESUMEN

The phase noise characteristics and laser stabilization time of a tunable laser under both static and fast switching operation is characterized using a dynamic linewidth measurement technique which employs a digital intradyne coherent receiver. The measurement technique utilizes a time domain frequency estimator to characterize the laser phase noise and also analyses the separate noise contributions to the overall laser linewidth. The performance of the measurement technique is validated using a phase noise emulator and a low linewidth (10 kHz) external cavity laser. The dynamic stabilization time, in terms of instantaneous frequency and linewidth, of a fast switching tunable DSDBR laser is subsequently investigated and we demonstrate that a minimum linewidth for a DSDBR laser can be realized within 50 ns of a wavelength switching event in a 5-channel 50 GHz spaced WDM system.

13.
Opt Express ; 19(26): B661-6, 2011 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-22274085

RESUMEN

We propose and demonstrate a technique to estimate the OSNR of an equalised QPSK signal based on the radial moments of the complex signal constellation. The technique is compared through simulation with maximum likelihood estimation and the effect of the block size used in the estimation is also assessed. The technique is verified experimentally and when combined with a single point calibration the OSNR of the input signal was estimated to within 0.5 dB.

14.
Opt Express ; 19(26): B770-6, 2011 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-22274101

RESUMEN

A burst mode 112 Gb/s DP-QPSK digital coherent optical receiver with parallel DSP suitable for implementation in a CMOS ASIC with a 218.75 MHz clock speed is presented. The receiver performance is validated in a five channel 50 GHz grid WDM burst switching experiment using a commercially available wavelength tunable laser as the local oscillator. A new equalizer initialization scheme that overcomes the degenerate convergence problem and ensures rapid convergence is introduced. We show that the performance of the tunable local oscillator is commensurate with burst mode coherent reception when differential decoding in employed and that required parallel DSP implementation does not seriously impair the polarization and frequency tracking performance of a digital coherent receiver under burst mode operation. We report a burst acquisition time of less than 200 ns.

15.
Artículo en Inglés | MEDLINE | ID: mdl-34000175

RESUMEN

OBJECTIVE: Novel approaches are needed to assist rural primary care physicians (PCPs) in caring for older patients living with depression and pain who are at an elevated suicide risk. To refine and improve a model of care (PREDICTOR: Pharmacy Identification and Primary Care Intervention of Older Adults at Risk for Suicide), we conducted qualitative interviews with rural PCPs about (1) caring for seniors with depression, pain, and suicidality and (2) their favored procedures for working with psychiatric consultants and the professional characteristics desired in an effective consultant. METHODS: The study utilized a best-practice approach (including double coding) for qualitative interviews with 10 PCPs practicing in rural Pennsylvania. PCPs were interviewed about 3 themes related to caring for older adults with depression, pain, and suicidal ideation and working with psychiatric consultants. The study was conducted from January 2019 to May 2019. RESULTS: Four primary themes emerged from the interviews. (1) Rural PCPs become comfortable managing depression in older adults out of necessity, but desire collaboration on more complex mental health care. (2) Comorbid depression and pain are universally described as related through a vicious cycle in older adults. (3) Rural PCPs experience varying comfort with prescribing opioids for pain management in older patients, but most prefer not to prescribe opioids, and some refuse to do so. (4) PCPs endorsed the PREDICTOR remote consultation model as potentially beneficial to themselves and their older patients, but strongly desired that the consultant work with them as collaborators and for a collegial professional relationship with the mental health specialist. CONCLUSIONS: Rural PCPs are comfortable with remote consultation for older patients living with depression but desire collegial relationships with these consultants, supporting a collaborative approach. We describe explicit plans for implementing these findings as we refine PREDICTOR, in efforts to promote PCP practice change.


Asunto(s)
Médicos de Atención Primaria , Anciano , Depresión/complicaciones , Depresión/terapia , Humanos , Salud Mental , Dolor , Derivación y Consulta
16.
Opt Express ; 18(15): 15672-81, 2010 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-20720949

RESUMEN

The performance of a cost-effective optical comb source using commercial off the shelf (COTS) components in a WDM passive optical network is demonstrated. Eight comb modes are individually modulated at 10.7 Gb/s and transmitted over 50 km of single mode fiber for downlink transmission. Error free performance is obtained for each comb line and a maximum performance difference of 1.4 dB is experienced between the eight channels. Colorless operation of the optical network unit is achieved by utilizing an integrated module consisting of a tunable laser and an electro-absorption modulator as an uplink transmitter. Finally the predicted downstream performance of the system, when all the channels are transmitted simultaneously, is numerically simulated.

17.
Chemphyschem ; 11(13): 2714-31, 2010 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-20730848

RESUMEN

Fuel cell performance is determined by the complex interplay of mass transport, energy transfer and electrochemical processes. The convolution of these processes leads to spatial heterogeneity in the way that fuel cells perform, particularly due to reactant consumption, water management and the design of fluid-flow plates. It is therefore unlikely that any bulk measurement made on a fuel cell will accurately represent performance at all parts of the cell. The ability to make spatially resolved measurements in a fuel cell provides one of the most useful ways in which to monitor and optimise performance. This Minireview explores a range of in situ techniques being used to study fuel cells and describes the use of novel experimental techniques that the authors have used to develop an 'experimental functional map' of fuel cell performance. These techniques include the mapping of current density, electrochemical impedance, electrolyte conductivity, contact resistance and CO poisoning distribution within working PEFCs, as well as mapping the flow of reactant in gas channels using laser Doppler anemometry (LDA). For the high-temperature solid oxide fuel cell (SOFC), temperature mapping, reference electrode placement and the use of Raman spectroscopy are described along with methods to map the microstructural features of electrodes. The combination of these techniques, applied across a range of fuel cell operating conditions, allows a unique picture of the internal workings of fuel cells to be obtained and have been used to validate both numerical and analytical models.


Asunto(s)
Suministros de Energía Eléctrica , Conductividad Eléctrica , Electroquímica , Electrodos , Electrólitos/química , Membranas Artificiales , Espectrometría Raman
18.
J Air Waste Manag Assoc ; 59(3): 310-20, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19320269

RESUMEN

The spatiotemporal variability of ground-level ozone (GLO) in the rural Annapolis Valley, Nova Scotia was investigated between August 29, 2006, and September 28, 2007, using Ogawa nitrite-impregnated passive diffusion samplers (PS). A total of 353 PS measurements were made at 17 ambient and 1 indoor locations over 18 sampling periods ranging from 2 to 4 weeks. The calculated PS detection limit was 0.8 +/- 0.02 parts per billion by volume (ppbv), for a 14-day sampling period. Duplicate samplers were routinely deployed at three sites and these showed excellent agreement (R2 values of 0.88 [n = 11], 0.95 [n = 17], and 0.96 [n = 17]), giving an overall PS imprecision value of 5.4%. Comparisons between PS and automated continuous ozone analyzers at three sites also demonstrated excellent agreement with R2 values of 0.82, 0.95, and 0.95, and gradients not significantly different from unity. The minimum, maximum, and mean (+/- 1 sigma) ambient annual GLO concentrations observed were 7.7, 72.1, and 34.3 +/- 10.1 ppbv, respectively. The three highest sampling sites had significantly greater (P = 0.032) GLO concentrations than three Valley floor sites, and there was a strong correlation between concentration and elevation (R2 = 0.82). Multivariate models were used to parameterize the observed GLO concentrations in terms of prevailing meteorology at an elevated site found at Kejimkujik National Park and also at a site on the Valley floor. Validation of the multivariate models using 30 months of historical meteorological data at these sites yielded R2 values of 0.70 (elevated site) and 0.61 (Valley floor). The mean indoor ozone concentration was 5.4 +/- 3.3 ppbv and related to ambient GLO concentration by the equation: indoor = 0.34 x ambient - 5.07. This study has demonstrated the suitability of PS for long-term studies of GLO over a wide geographic area and the effect of topographical and meteorological influences on GLO in this region.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Ozono/análisis , Estaciones del Año , Contaminación del Aire Interior/análisis , Atmósfera/química , Geografía , Análisis Multivariante , Nitritos/química , Nueva Escocia , Reproducibilidad de los Resultados , Factores de Tiempo
19.
Opt Express ; 16(15): 11281-8, 2008 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-18648446

RESUMEN

The optimization of a wavelength tunable RZ transmitter, consisting of an electro-absorption modulator and a SG DBR tunable laser, is carried out using a linear spectrogram based characterization and leads to 1500 km transmission at 42.7 Gb/s independent of the operating wavelength. We demonstrate that, to ensure optimum and consistent transmission performance over a portion of the C-band, the RF drive and bias conditions of the EAM must be varied at each wavelength. The sign and magnitude of the pulse chirp (characterized using the linear spectrographic technique) is therefore tailored to suit the dispersion map of the transmission link. Results achieved show that by optimizing the drive and DC bias applied to the EAM, consistent transmission performance can be achieved over a wide wavelength range. Failure to optimize the EAM drive conditions at each wavelength can lead to serious degradation in system performance.


Asunto(s)
Tecnología de Fibra Óptica/instrumentación , Microondas , Óptica y Fotónica/instrumentación , Procesamiento de Señales Asistido por Computador/instrumentación , Telecomunicaciones/instrumentación , Transductores , Diseño de Equipo , Análisis de Falla de Equipo , Análisis Espectral/métodos
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