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2.
Support Care Cancer ; 28(8): 3801-3812, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31832822

RESUMO

PURPOSE: To compare febrile neutropenia (FN) incidence and hospitalization among breast cancer patients on docetaxel with no granulocyte colony-stimulating factors (GCSF) primary prophylaxis (PP), 4/5-day PP, or 7-day PP. METHODS: We identified 3916 breast cancer patients using docetaxel-cyclophosphamide (TC), doxorubicin-cyclophosphamide then docetaxel (AC-T), fluorouracil-epirubicin-cyclophosphamide then docetaxel (FEC-T), docetaxel-carboplatin-trastuzumab (TJH), or docetaxel-doxorubicin-cyclophosphamide (TAC) from a hospital pharmacy dispensing database in Hong Kong between 2014 and 2016. Patients were offered GCSF within 5 days since administering docetaxel. Outcomes included FN incidence, time to first hospitalization, hospitalization rate, and duration. RESULTS: In TC regimen, FN incidence (with odds ratio, OR) of patients with no PP, 4/5-day PP, and 7-day PP was 21.69%, 7.95% (OR 0.31, p < 0.001), and 5.33% (OR 0.20, p < 0.001), respectively. In TJH regimen, FN incidence of patients with no PP, 4/5-day PP, and 7-day PP was 38.26%, 8.33% (OR 0.15, p < 0.001), and 8.57% (OR 0.15, p < 0.001), respectively. FN incidence of patients on AC-T regimen with no PP and 4/5-day PP was 20.93% and 6.84%, respectively (OR 0.28, p = 0.005); with FEC-T regimen, the incidence was 9.91% and 4.77%, respectively (OR 0.46, p = 0.035). Only 3.27% FN cases were not hospitalized. Mean (±standard deviation, SD) time to first hospitalization was 8.21 ± 2.44 days. Mean (±SD) duration of hospitalization for patients with no PP, 4/5-day PP, and 7-day PP was 4.66 ± 2.60, 4.37 ± 2.85, and 5.12 ± 2.97 days, respectively. CONCLUSION: GCSF prophylaxis in breast cancer patients on docetaxel could reduce FN incidence and hospitalization. 4/5-day PP demonstrated similar efficacy to 7-day PP with superior saving benefits on healthcare expenditure.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias da Mama/complicações , Docetaxel/efeitos adversos , Neutropenia Febril/etiologia , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Feminino , Hospitalização , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
3.
Phys Med Biol ; 63(21): 215019, 2018 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-30372420

RESUMO

Margins are employed in radiotherapy treatment planning to mitigate the dosimetric effects of geometric uncertainties for the clinical target volume (CTV). Unfortunately, whilst the use of margins can increase the probability that sufficient dose is delivered to the CTV, it can also result in delivering high dose of radiation to surrounding organs at risk (OARs). We expand on our previous work on beam-dependent margins and propose a novel adaptive margin concept, where margins are moulded away from selected OARs for better OAR-high-dose sparing, whilst maintaining similar dose coverage probability to the CTV. This, however, comes at a cost of a larger irradiation volume, and thus can negatively impact other structures. We investigate the impact of the adaptive margin concept when applied to prostate radiotherapy treatments, and compare treatment plans generated using our beam-dependent margins without adaptation, with adaption from the rectum and with adaptation from both the rectum and bladder. Five prostate patients were used in this planning study. All plans achieved similar dose coverage probability, and were able to ensure at least 90% population coverage with the target receiving at least 95% of the prescribed dose to [Formula: see text]. We observed overall better high-dose sparing to OARs that were considered when using the adapted beam-dependent PTVs, with the degree of sparing dependent on both the number of OARs under consideration as well as the relative position between the CTV and the OARs.


Assuntos
Órgãos em Risco/efeitos da radiação , Planejamento da Radioterapia Assistida por Computador/métodos , Humanos , Masculino , Probabilidade , Neoplasias da Próstata/radioterapia , Radiometria , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada , Reto/efeitos da radiação , Incerteza
5.
Phys Med Biol ; 62(12): 4917-4928, 2017 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-28379156

RESUMO

Radiotherapy treatment planning for use with high-energy photon beams currently employs a binary approach in defining the planning target volume (PTV). We propose a margin concept that takes the beam directions into account, generating beam-dependent PTVs (bdPTVs) on a beam-by-beam basis. The resulting degree of overlaps between the bdPTVs are used within the optimisation process; the optimiser effectively considers the same voxel to be both target and organ at risk (OAR) with fractional contributions. We investigate the impact of this novel approach when applied to prostate radiotherapy treatments, and compare treatment plans generated using beam dependent margins to conventional margins. Five prostate patients were used in this planning study, and plans using beam dependent margins improved the sparing of high doses to target-surrounding OARs, though a trade-off in delivering additional low dose to the OARs can be observed. Plans using beam dependent margins are observed to have a slightly reduced target coverage. Nevertheless, all plans are able to satisfy 90% population coverage with the target receiving at least 95% of the prescribed dose to [Formula: see text].


Assuntos
Planejamento da Radioterapia Assistida por Computador/métodos , Humanos , Masculino , Órgãos em Risco/efeitos da radiação , Fótons/efeitos adversos , Fótons/uso terapêutico , Probabilidade , Neoplasias da Próstata/radioterapia , Dosagem Radioterapêutica
6.
Cell Biochem Funct ; 34(3): 113-32, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26914991

RESUMO

The human cardiovascular system is a complex arrangement of specialized structures with distinct functions. The molecular landscape, including the genome, transcriptome and proteome, is pivotal to the biological complexity of both normal and abnormal mammalian processes. Despite our advancing knowledge and understanding of cardiovascular disease (CVD) through the principal use of rodent models, this continues to be an increasing issue in today's world. For instance, as the ageing population increases, so does the incidence of heart valve dysfunction. This may be because of changes in molecular composition and structure of the extracellular matrix, or from the pathological process of vascular calcification in which bone-formation related factors cause ectopic mineralization. However, significant differences between mice and men exist in terms of cardiovascular anatomy, physiology and pathology. In contrast, large animal models can show considerably greater similarity to humans. Furthermore, precise and efficient genome editing techniques enable the generation of tailored models for translational research. These novel systems provide a huge potential for large animal models to investigate the regulatory factors and molecular pathways that contribute to CVD in vivo. In turn, this will help bridge the gap between basic science and clinical applications by facilitating the refinement of therapies for cardiovascular disease.


Assuntos
Doenças Cardiovasculares , Modelos Animais de Doenças , Animais , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Humanos
8.
Eye (Lond) ; 28(8): 958-61, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24833183

RESUMO

PURPOSE: Fibres are regularly found within the delivery cartridge (DC) and in the anterior chamber (AC) during phacoemulsification cataract surgery (PCS) and postoperatively. The purpose of this study was to identify their frequency and possible significance. SETTING: Dedicated ophthalmic day surgery. DESIGN: Prospective, consecutive, single-surgeon, cohort study. METHODS: In 639 eyes undergoing PCS, the presence of fibres was documented in or on both the DC and in the AC intraoperatively, and in the AC postoperatively. The intraoperative method of fibre removal was documented. Corrected distance visual acuity (CDVA) was recorded preoperatively, and at day 1, week 1, and week 4 postoperatively. The incidence of clinical cystoid macular oedema (CMO) and endophthalmitis in the retained fibre subcohort was compared with that of the non-fibre subcohort. RESULTS: A total of 5.2% of the operated eyes had a fibre or fibres in or on the DC, which in all cases was removed with forceps intraoperatively. A total of 14.6% of operated eyes had a fibre or fibres in the AC intraoperatively; these were removed by irrigation/aspiration. Postoperatively, five eyes (0.78%) had a fibre in the AC. There was no significant difference in postoperative CDVA between the fibre and non-fibre subcohorts (P=0.26), and no clinically significant CMO or endophthalmitis in either subcohort. CONCLUSIONS: Most fibres seen on the DC or in the eye are sterile and non-inflammatory. However, there have been reports of endophthalmitis attributed to retained fibres. In this study, there were no complications attributable to the fibres, but their removal may minimise any adverse potential.


Assuntos
Câmara Anterior/patologia , Corpos Estranhos no Olho/diagnóstico , Complicações Intraoperatórias , Facoemulsificação , Complicações Pós-Operatórias , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Endoftalmite/epidemiologia , Corpos Estranhos no Olho/etiologia , Corpos Estranhos no Olho/cirurgia , Feminino , Humanos , Implante de Lente Intraocular/instrumentação , Edema Macular/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Acuidade Visual
9.
Rhinology ; 52(1): 78-83, 2014 03.
Artigo em Inglês | MEDLINE | ID: mdl-24618633

RESUMO

BACKGROUND: The purpose of this study was to qualitatively characterise patients with midfacial segment pain (MSP) using the Sino-Nasal Outcome Test (SNOT). The data will provide a detailed overview of the physical and psychological impact on patients'well-being, and how it compares with the normal, healthy population. METHODS: Suitable patients were prospectively identified from the Multi-disciplinary Facial Pain Clinic at the Royal Liverpool University Hospital, based on the diagnostic criteria for MSP. The pre-treatment SNOT-22 of these patients were also compared to patients with chronic rhinosinusitis and normal healthy volunteers. RESULTS: Twenty-nine consecutive patients with a diagnosis of MSP were identified, and compared with 30 CRS patients and 34 healthy volunteers. The average SNOT-22 scores of MSP and CRS patients were higher than normal healthy volunteers. Patients with CRS had the highest rhinological subscale SNOT scores compared to normal healthy volunteers and MSP. Conversely, the reported ear and facial symptoms of MSP patients were most unfavourable. A similar trend was observed in reported sleep function where MSP patients recorded higher subscale scores than the other two cohorts. The subscale mean score for psychological function of MSP patients was not significant when compared to the mean score of patients diagnosed with CRS. CONCLUSION: MSP has an adverse impact on both physical and psychological well-being. The subtle differences in the SNOT subscores between MSP and CRS have provided greater insight into the character and disease impact of MSP. We propose that the SNOT may be suitably utilised in MSP to document disease severity and measure response to treatment.


Assuntos
Doença Crônica/terapia , Endoscopia/métodos , Dor Facial/terapia , Sinusite/fisiopatologia , Tomografia Computadorizada por Raios X/métodos , Administração Intranasal , Dor Facial/diagnóstico , Humanos , Estudos Prospectivos , Sinusite/diagnóstico , Sinusite/terapia , Inquéritos e Questionários , Resultado do Tratamento
10.
Hong Kong Med J ; 20(1): 24-31, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23784532

RESUMO

OBJECTIVES. To review the characteristics of a series of obstetric patients admitted to the intensive care unit in a regional hospital in 2006-2010, to compare them with those of a similar series reported from the same hospital in 1989-1995 and a series reported from another regional hospital in 1998-2007. DESIGN. Retrospective case series. SETTING. A regional hospital in Hong Kong. PATIENTS. Obstetric patients admitted to the Intensive Care Unit of Kwong Wah Hospital from 1 January 2006 to 31 December 2010. RESULTS. From 2006 to 2010, there were 67 such patients admitted to the intensive care unit (0.23% of total maternities and 2.34% of total intensive care unit admission), which was a higher incidence than reported in two other local studies. As in the latter studies, the majority were admitted postpartum (n=65, 97%), with postpartum haemorrhage (n=39, 58%) being the commonest cause followed by pre-eclampsia/eclampsia (n=17, 25%). In the current study, significantly more patients had had elective caesarean sections for placenta praevia but fewer had had a hysterectomy. The duration of intensive care unit stay was shorter (mean, 1.8 days) with fewer invasive procedures performed than in the two previous studies, but maternal and neonatal mortality was similar (3% and 6%, respectively). CONCLUSION. Postpartum haemorrhage and pregnancy-induced hypertension were still the most common reasons for intensive care unit admission. There was an increasing trend of intensive care unit admissions following elective caesarean section for placenta praevia and for early aggressive intervention of pre-eclampsia. Maternal mortality remained low but had not decreased. The intensive care unit admission rate by itself might not be a helpful indicator of obstetric performance.


Assuntos
Unidades de Terapia Intensiva/estatística & dados numéricos , Complicações do Trabalho de Parto/terapia , Adulto , Cesárea , Procedimentos Cirúrgicos Eletivos , Feminino , Hong Kong , Humanos , Hipertensão Induzida pela Gravidez/terapia , Tempo de Internação , Mortalidade Materna/tendências , Placenta Prévia/cirurgia , Hemorragia Pós-Parto/terapia , Pré-Eclâmpsia/cirurgia , Gravidez , Estudos Retrospectivos
11.
Opt Express ; 21(3): 2869-74, 2013 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-23481745

RESUMO

In this work, we propose and demonstrate a stable and wavelength-tunable erbium-doped fiber (EDF) ring laser. Here, a silicon-on-insulator (SOI)-based silicon-micro-ring-resonator (SMRR) is used as the wavelength selective element inside the fiber ring cavity. A uniform period grating coupler (GC) is used to couple between the SMRR and single mode fiber (SMF) and serves also as a polarization dependent element in the cavity. The output lasing wavelength of the proposed fiber laser can be tuned at a tuning step of 2 nm (defined by the free spectral range (FSR) of the SMRR) in a bandwidth of 35.2 nm (1532.00 to 1567.20 nm), which is defined by the gain of the EDF. The optical-signal-to-noise-ratio (OSNR) of each lasing wavelength is larger than 42.0 dB. In addition, the output stabilities of power and wavelength are also discussed.


Assuntos
Lasers de Estado Sólido , Lasers , Silício/química , Transdutores , Desenho de Equipamento , Análise de Falha de Equipamento , Miniaturização
12.
Mar Pollut Bull ; 66(1-2): 158-63, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23177239

RESUMO

Global marine vessels emissions are adversely affecting human health particularly in southeast Asia. But health burdens from both ocean- and river-going vessels in Pearl River Delta (PRD) regions are not quantified. We estimated the potential health impacts using pooled relative risks of mortality and hospital admissions in China, and the model derived concentrations of sulfur dioxide (SO2), particulate matter (PM10), nitrogen dioxide (NO2) and ozone (O3) due to vessels emissions. SO2 concentrations due to marine emissions in Hong Kong were 13.6 µg m⁻³ compared with 0.7 µg m⁻³ in PRD regions that were far from the marine vessels. In PRD regions, the estimated annual numbers (per million people) of excess deaths from all natural causes and hospital admissions from cardiorespiratory causes attributable to SO2, NO2, O3 and PM10 combined from marine emissions were 45 and 265 respectively. Marine emission control measures could contribute a large reduction in mortality and hospital admissions in PRD regions especially in Hong Kong.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental/métodos , Avaliação do Impacto na Saúde , China , Humanos , Dióxido de Nitrogênio/análise , Ozônio/análise , Material Particulado/análise , Rios , Dióxido de Enxofre/análise
13.
Hong Kong Med J ; 19 Suppl 9: 4-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24473581

RESUMO

1. Individuals with higher global functioning, better readiness for action, and lower self-esteem decrement tend to have better psychosocial treatment participation. 2. Individuals with lesser psychiatric symptoms are more likely to have better treatment attendance. 3. Self-stigmatisation undermines treatment compliance. Its indirect effects can be mediated via stages of change and insight. 4. The self-stigma reduction programme may reduce self-esteem decrement, promote readiness for changing own problematic behaviours, and enhance psychosocial treatment compliance. However, its therapeutic effects were not maintained during the 6-month follow-up.


Assuntos
Cooperação do Paciente , Esquizofrenia/terapia , Psicologia do Esquizofrênico , Estigma Social , Adulto , Povo Asiático , Estudos Transversais , Feminino , Humanos , Masculino
14.
Opt Express ; 20(21): 23019-24, 2012 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-23188265

RESUMO

In this work, we experimentally demonstrate a bi-directional transmission link using light emitting diode (LED) visible light communication (VLC) for both downlink and uplink paths. Time-division-duplex (TDD) is proposed and demonstrated to significantly eliminate the reflection interference in VLC. A free space bi-directional transmission of 2 m using simple on-off keying (OOK) modulation with bit error rate (BER) of < 10(-5) in both directions are achieved. Moreover, the influence of reflection interference is analyzed, showing the proposed scheme can significantly eliminate the reflection interference.


Assuntos
Artefatos , Iluminação/instrumentação , Dispositivos Ópticos , Semicondutores , Processamento de Sinais Assistido por Computador/instrumentação , Telecomunicações/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
15.
Opt Express ; 19(12): 11312-7, 2011 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-21716361

RESUMO

The integration of passive optical network (PON) and radio-over-fiber (ROF) networks could provide broadband services for both fixed and mobile users in a single and low-cost platform. Combining the long-reach (LR)-PON (>100 km) and the LR-ROF can further reduce the cost by simplifying the network architecture, sharing the same optical components and extending the coverage of ROF network. However, the transmission and distribution of ROF signal in LR network is very challenging due to the chromatic dispersion generated periodic power fading and code time-shifting effects in the optical fiber. In this work, we propose and experimentally demonstrate a LR-ROF signal distribution using single-sideband (SSB)-ROF signal generated by a silicon ring-modulator. The silicon modulator is compact and has low power consumption. Besides, one unique feature of the silicon ring-modulator is that it only modulates the signal wavelength at the resonant null. This makes it very suitable for the generation of the SSB-ROF signal. Numerical comparison of the SSB-ROF with the double-sideband (DSB)-ROF and optical carrier suppress (OCS)-ROF signals; as well as the fabrication of the silicon ring-modulator will be discussed.

17.
Lupus ; 19(3): 330-3, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19897521

RESUMO

Patients with systemic lupus erythematosus (SLE) are susceptible to the development of lymphoproliferative disorders and postulated causes include intrinsic defects in immune surveillance and iatrogenic administration of immunosuppressants. Since the introduction of mycophenolate mofetil (MMF) to the immunosuppressive regimen for the management of post-organ transplantation, there have been reports of primary lymphoma of the central nervous system (PCNSL). MMF has been widely used to treat active SLE patients with Class IV lupus nephritis. In addition to two previously reported cases of PCNSL among SLE patients on long-term MMF, we report a third patient who has been on treatment with MMF for 8 years. The histology showed features compatible with diffuse large B-cell lymphoma with strong immunohistochemical staining for CD20 and positive signal for Epstein-Barr virus (EBV)-encoded RNA by in-situ hybridization that is similar to other case reports, suggesting EBV driven B-cell lymphoproliferative disease. The patient responded to withdrawal of MMF, intravenous methotrexate, rituximab and whole brain radiotherapy. With the increasing use of MMF in active renal as well as non-renal exacerbations of SLE, PCNSL should be included in the differential diagnosis in patients who present with gradual onset of focal neurological deficit.


Assuntos
Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Linfoma Difuso de Grandes Células B/terapia , Ácido Micofenólico/análogos & derivados , Adulto , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Murinos , Antimetabólitos Antineoplásicos/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias do Sistema Nervoso Central/etiologia , Neoplasias do Sistema Nervoso Central/terapia , Neoplasias do Sistema Nervoso Central/virologia , Infecções por Vírus Epstein-Barr/complicações , Feminino , Humanos , Imunossupressores/efeitos adversos , Linfoma Difuso de Grandes Células B/etiologia , Linfoma Difuso de Grandes Células B/virologia , Metotrexato/uso terapêutico , Ácido Micofenólico/efeitos adversos , Ácido Micofenólico/uso terapêutico , Rituximab
18.
Environ Int ; 35(7): 1040-7, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19535140

RESUMO

Nine groups of food items (freshwater fish, marine fish, pork, chicken, chicken eggs, leafy, non-leafy vegetables, rice and flour) and three types of human samples (human milk, maternal serum and cord serum) were collected for the analysis of PCDD/Fs. Results of chemical analysis revealed PCDD/Fs concentrations (pg g(-1) fat) in the following ascending order: pork (0.289 pg g(-1) fat), grass carp (Ctenopharyngodon idellus) (freshwater fish) (0.407), golden thread (Nemipterus virgatus) (marine fish) (0.511), chicken (0.529), mandarin fish (Siniperca kneri) (marine fish) (0.535), chicken egg (0.552), and snubnose pompano (Trachinotus blochii) (marine fish) (1.219). The results of micro-EROD assay showed relatively higher PCDD/Fs levels in fish (2.65 pg g(-1) fat) when compared with pork (0.47), eggs (0.33), chicken (0.13), flour (0.07), vegetables (0.05 pg g(-1) wet wt) and rice (0.05). The estimated average daily intake of PCDD/Fs of 3.51 pg EROD-TEQ/kg bw/day was within the range of WHO Tolerable Daily Intake (1-4 pg WHO-TEQ/kg bw/day) and was higher than the Provisional Tolerable Daily Intake (PMTL) (70 pg for dioxins and dioxin-like PCBs) recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) [Joint FAO/WHO Expert Committee on Food Additives (JECFA), Summary and conclusions of the fifty-seventh meeting, JECFA, 2001.]. Nevertheless, the current findings were significantly lower than the TDI (14 pg WHO-TEQ/kg/bw/day) recommended by the Scientific Committee on Food of the Europe Commission [European Scientific Committee on Food (EU SCF), Opinions on the SCF on the risk assessment of dioxins and dioxin-like PCBs in food, 2000.]. However, it should be noted that micro-EROD assay overestimates the PCDD/Fs levels by 2 to 7 folds which may also amplify the PCDD/Fs levels accordingly. Although the levels of PCDD/Fs obtained from micro-EROD assay were much higher than those obtained by chemical analysis by 2 to 7 folds, it provides a cost-effective and rapid screening of dioxin levels in food and human samples.


Assuntos
Benzofuranos/análise , Poluentes Ambientais/análise , Análise de Alimentos , Dibenzodioxinas Policloradas/análogos & derivados , Benzofuranos/sangue , Benzofuranos/metabolismo , Biomarcadores/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Dibenzofuranos Policlorados , Dioxinas/análise , Dioxinas/metabolismo , Ovos/análise , Poluentes Ambientais/sangue , Poluentes Ambientais/metabolismo , Feminino , Sangue Fetal/química , Farinha/análise , Hong Kong , Humanos , Carne/análise , Leite Humano/química , Oryza/química , Dibenzodioxinas Policloradas/análise , Dibenzodioxinas Policloradas/sangue , Dibenzodioxinas Policloradas/metabolismo , Medição de Risco , Verduras/química
20.
Opt Lett ; 31(17): 2535-7, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16902610

RESUMO

We demonstrate orthogonal label switching by using a dark-return-to-zero (DRZ) payload and differential phase-shift keying (DPSK) label generated by a dispersion-flattened photonic-crystal fiber. The high extinction ratio of both the payload and label improves the receiver margin. The DRZ payload introduces little cross talk to the DPSK label due to the RZ-like output of the demodulated DPSK. Simulations are performed to study the eye-closure penalty of the payload and label at different DRZ pulse widths. We compare the DRZ/DPSK with the RZ and DPSK signals numerically at the same data rate and show that the DRZ/DPSK has a strong tolerance to the polarization-mode dispersion. The DRZ/DPSK has a more compact spectrum suitable for the strong filtering requirements in WDM systems.

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