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Orthogonal chirp-division multiplexing (OCDM) has been recently proposed as an attractive modulation technique for realizing high-speed coherent lightwave systems in virtue of its resilience against system impairments. However, the complex-valued OCDM signal is not directly viable for optical intensity modulation and direct detection (IM/DD) systems. In this paper, a double-sideband (DSB)-modulated OCDM scheme is proposed for short-reach, high-speed IM/DD systems. In the proposed scheme, the real-valued OCDM signal is generated by a simple digital up-conversion technique, which converts the complex-baseband signal to a passband to avoid the aliasing for DSB modulation. At the receiver, inverse operations revert the signal back to the baseband for demodulation. Experiments were carried out to validate the feasibility and advantages of the proposed scheme, and OCDM signals with data rates up to 174.5 Gbit/s were successfully demonstrated. The results confirm that the proposed IM/DD-OCDM system is more robust to impairments and thus achieves better performance than a discrete multi-tone system.
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We demonstrate how to optimize the performance of PAM-4 transmitters based on lumped Silicon Photonic Mach-Zehnder Modulators (MZMs) for short-reach optical links. Firstly, we analyze the trade-off that occurs between extinction ratio and modulation loss when driving an MZM with a voltage swing less than the MZM's Vπ. This is important when driver circuits are realized in deep submicron CMOS process nodes. Next, a driving scheme based upon a switched capacitor approach is proposed to maximize the achievable bandwidth of the combined lumped MZM and CMOS driver chip. This scheme allows the use of lumped MZM for high speed optical links with reduced RF driver power consumption compared to the conventional approach of driving MZMs (with transmission line based electrodes) with a power amplifier. This is critical for upcoming short-reach link standards such as 400Gb/s 802.3 Ethernet. The driver chip was fabricated using a 65nm CMOS technology and flip-chipped on top of the Silicon Photonic chip (fabricated using IMEC's ISIPP25G technology) that contains the MZM. Open eyes with 4dB extinction ratio for a 36Gb/s (18Gbaud) PAM-4 signal are experimentally demonstrated. The electronic driver chip has a core area of only 0.11mm2 and consumes 236mW from 1.2V and 2.4V supply voltages. This corresponds to an energy efficiency of 6.55pJ/bit including Gray encoder and retiming, or 5.37pJ/bit for the driver circuit only.
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OBJECTIVES: To evaluate the prognostic value of carcinoembryonic antigen (CEA) density and other clinicopathological factors for percutaneous ablation of pulmonary metastases from colorectal cancer. METHODS: CEA density was calculated as: "absolute serum CEA pre-ablation/volume of all lung metastases [mm3]". Median CEA density was the cut-off for high and low groups. Cox-regression was used to determine prognostic factors for survival. RESULTS: A total of 85 patients (102 ablation sessions) were followed for a median of 27 months. High CEA density was significantly associated with worse overall survival compared to low CEA density (adjusted HR: 2.12; 95 % CI: 1.22-3.70, p=0.002; median survival: 25.7 vs. 44.3 months). The interval between primary resection of the colorectal carcinoma and first ablation was also a prognostic factor, a duration >24 months being associated with better survival compared to a shorter interval (0-24 months) (adjusted HR: 0.55; 95 % CI: 0.31-0.98, p=0.04). Moreover, a disease-free interval >24 months was significantly associated with low CEA density compared to a shorter interval (0-24 months) (adjusted OR: 0.29; 95 % CI: 0.11-0.77, p=0.01). CONCLUSIONS: Serum CEA density and interval between primary resection of a colorectal carcinoma and pulmonary ablation are independent prognostic factors for overall survival. In two patients with identical CEA serum levels, the patient with the lower/smaller pulmonary tumour load would have a worse prognosis than the one with the higher/larger pulmonary metastases. KEY POINTS: ⢠CEA density is an independent prognostic factor for colorectal pulmonary metastases. ⢠A lower CEA density is associated with better overall survival. ⢠CEA may play a functional role in tumour progression. ⢠High CEA density is associated with smaller tumours. ⢠Interval between pulmonary ablation and primary colorectal carcinoma is a prognostic factor.
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Antígeno Carcinoembrionario/sangre , Neoplasias Colorrectales/sangre , Neoplasias Pulmonares/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/sangre , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/secundario , Masculino , Persona de Mediana Edad , Nueva Gales del Sur/epidemiología , Pronóstico , Tasa de Supervivencia/tendencias , Adulto JovenRESUMEN
We simulate and experimentally demonstrate a novel all-optical clock recovery technique for a BPSK OFDM superchannel. Four-wave mixing in SOAs is used to strip the modulation from the superchannel sub-carriers, two of which are filtered and beat together in a photodiode to recover the clock.
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Percutaneous image-guided thermal ablation is safe and efficacious in achieving local control and improving outcome in the treatment of both early stage non-small-cell lung cancer and pulmonary metastatic disease, in which surgical treatment is precluded by comorbidity, poor cardiorespiratory reserve, or unfavorable disease distribution. Radiofrequency ablation is the most established technology, but new thermal ablation technologies such as microwave ablation and cryoablation may offer some advantages. The use of advanced techniques, such as induced pneumothorax and the popsicle stick technique, or combining thermal ablation with radiotherapy, widens the treatment options available to the multidisciplinary team. The intent of this article is to provide the reader with a practical knowledge base of pulmonary ablation by concentrating on indications, techniques, and follow-up.
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Ablación por Catéter/métodos , Neoplasias Pulmonares/cirugía , Radiografía Intervencional , Ablación por Catéter/instrumentación , Humanos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/secundario , Pronóstico , Tasa de SupervivenciaRESUMEN
We describe the first experimental demonstration of a novel all-optical phase discrimination technique, which can separate the two orthogonal phase components of a signal onto different frequencies. This method exploits nonlinear mixing in a semiconductor optical amplifier (SOA) to separate a 10.65 Gbaud QPSK signal into two 10.65 Gb/s BPSK signals which are then demodulated using a delay interferometer (DI). Eye diagrams and spectral measurements verify correct operation and a conversion efficiency greater than 9 dB is observed on both output BPSK channels when compared with the input QPSK signal.
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INTRODUCTION: High-flow priapism is a rare condition with limited data in the literature, particularly in Australia. There is therefore no clear consensus regarding treatment. We aim to present our institutional network experience in managing this condition over the last decade with super-selective gelatin sponge (Gelfoam) embolisation of the internal pudendal artery. METHODS: We retrospectively searched for and reviewed the patient records of all cases of priapism encountered within our multicentre institutional network over the last 10 years. Of these, the cases of high-flow priapism treated with embolisation were analysed in depth and compared with the current literature. RESULTS: Overall, 93 patients in our network were diagnosed with priapism from 1 January 2012 to 1 January 2022. And 89 of these patients (96%) had low-flow priapism and four patients (4%) had high-flow priapism. Of these four patients, two were treated within our network with super-selective Gelfoam embolisation of the internal pudendal artery. Following embolisation, both patients achieved rapid detumescence and returned to baseline premorbid erectile function. There was no report of recurrence or erectile dysfunction on follow-up. CONCLUSION: Super-selective embolisation of the internal pudendal artery should be considered as a treatment option for high-flow priapism, with Gelfoam as an appropriate temporary embolic agent of choice. We show that it was a safe and effective option for the patients treated in this series, enabling quick and long-term return to baseline erectile function. Our results support data provided by the limited number of cases in the literature.
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Embolización Terapéutica , Disfunción Eréctil , Priapismo , Masculino , Humanos , Priapismo/diagnóstico por imagen , Priapismo/terapia , Esponja de Gelatina Absorbible/uso terapéutico , Estudios Retrospectivos , Pene/diagnóstico por imagen , Pene/irrigación sanguínea , Embolización Terapéutica/métodosRESUMEN
In 2010, 65 diseases and conditions were nationally notifiable in Australia. States and territories reported a total of 209,079 notifications of communicable diseases to the National Notifiable Diseases Surveillance System, a decrease of 12% on the number of notifications in 2009. This decrease was largely due to a reduction of influenza compared with the influenza A(H1N1) pandemic 2009. In 2010, the most frequently notified diseases were sexually transmissible infections (86,620 notifications, 41.4% of total notifications), vaccine preventable diseases (61,964 notifications, 29.6% of total notifications), and gastrointestinal diseases (31,548 notifications, 15.1% of total notifications). There were 18,302 notifications of bloodborne diseases; 8,244 notifications of vectorborne diseases; 1,866 notifications of other bacterial infections; 532 notifications of zoonoses and 3 notifications of quarantinable diseases.
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Enfermedades Transmisibles/epidemiología , Notificación de Enfermedades , Vigilancia de la Población , Distribución por Edad , Animales , Informes Anuales como Asunto , Australia/epidemiología , Enfermedades Transmisibles/historia , Historia del Siglo XXI , Humanos , Estaciones del Año , Zoonosis/epidemiologíaRESUMEN
We report on the novel all-optical generation of duobinary (DB) and alternate-mark-inversion (AMI) modulation formats at 42.6 Gb/s from an input on-off keyed signal. The modulation converter consists of two semiconductor optical amplifier (SOA)-based Mach-Zehnder interferometer gates. A detailed SOA model numerically confirms the operational principles and experimental data shows successful AMI and DB conversion at 42.6 Gb/s. We also predict that the operational bandwidth can be extended beyond 40 Gb/s by utilizing a new pattern-effect suppression scheme, and demonstrate dramatic reductions in patterning up to 160 Gb/s. We show an increasing trade-off between pattern-effect reduction and mean output power with increasing bitrate.
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Amplificadores Electrónicos , Interferometría/instrumentación , Dispositivos Ópticos , Procesamiento de Señales Asistido por Computador/instrumentación , Telecomunicaciones/instrumentación , Diseño de Equipo , Análisis de Falla de EquipoRESUMEN
We present a 62-year-old gentleman with rapidly forming abdominal pseudoaneurysms due to segmental arterial mediolysis (SAM). With rupture of his pseudoaneurysms, he underwent angiography and successful coil embolisation. In this case, we demonstrate the potential for rapid progression of pseudoaneurysms in SAM, with the need for prompt diagnosis and urgent endovascular intervention.
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We report remarkably fast and strongly wavelength-dependent gain recovery in a single SOA without the aid of an offset filter. Full gain recovery times as short as 9 ps were observed in pump-probe measurements when pumping to the blue wavelength side of a continuous wave probe, in contrast to times of 25 to 30 ps when pumping to the red wavelength side. Experimental and numerical analysis indicate that the long effective length and high gain led to deep saturation of the second half of the SOA by the probe. The consequent absorption of blue-shifted pump pulses in this region resulted in device dynamics analogous to those of the Turbo-Switch.
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Amplificadores Electrónicos , Dispositivos Ópticos , Semiconductores , Procesamiento de Señales Asistido por Computador/instrumentación , Simulación por Computador , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Modelos Teóricos , Dinámicas no LinealesRESUMEN
RATIONALE AND OBJECTIVES: To measure the impact of 1-year interventional fellowship training on fluoroscopic time and contrast media utilization in uterine artery embolization (UAE). MATERIALS AND METHODS: Retrospective single institution analysis of 323 consecutive UAEs performed by 12 interventional fellows using a standardized protocol. Fluoroscopy time and contrast media volume were recorded for each patient and correlated with stage of fellowship training. Preprocedure uterine volume (using MRI or ultrasound) was used as a measure of procedural complexity. Regression analysis was conducted per trainee factoring in duration of training, procedure number, supervising radiologist, uterine volume, and outcome variables of fluoroscopy time and contrast media volume. RESULTS: Median number of patients treated per trainee was 27 (range, 16-43) with mean fluoroscopic time 24.5 minutes (range, 4-90 min) and mean contrast volume 190 mL (range, 50-320 mL). Increasing uterine volume had no significant effect (P > .05) on fluoroscopic time but significantly increased (P < .001) contrast media volume. Significant training effect was identified with decrease in fluoroscopic time (P < .001) and decrease in contrast volume (P = .02) over training. Over the course of a 1-year fellowship, these summed to a decrease of 12 minutes in UAE fluoroscopy time and 17 mL less contrast. CONCLUSION: A significant (P < .05) training effect that is clinically relevant was demonstrated over the course of a yearlong interventional radiology fellowship program in performance of a standardized protocol for UAE. This data supports fellowship training as a basis for UAE credentialing and privileging.
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Competencia Clínica , Educación de Postgrado en Medicina/métodos , Becas , Radiología Intervencionista/educación , Embolización de la Arteria Uterina/educación , Medios de Contraste/administración & dosificación , Evaluación Educacional , Femenino , Fluoroscopía , Humanos , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Ácidos Triyodobenzoicos , Ultrasonografía Intervencional , Embolización de la Arteria Uterina/normasRESUMEN
Direct caroticocavernous fistula (CCF) has traditionally been treated by detachable balloon placement within the affected cavernous sinus. We describe a case of a direct CCF treated solely with flow-diverting stents. These novel devices may offer a simpler and potentially safer vessel-sparing option in this rare condition.
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Fístula del Seno Cavernoso de la Carótida/cirugía , Stents , Enfermedades del Nervio Abducens/etiología , Accidentes de Tránsito , Angiografía de Substracción Digital , Aspirina/uso terapéutico , Lesiones Encefálicas/complicaciones , Lesiones Encefálicas/diagnóstico por imagen , Arteria Carótida Interna/cirugía , Fístula del Seno Cavernoso de la Carótida/etiología , Fístula del Seno Cavernoso de la Carótida/patología , Angiografía Cerebral , Clopidogrel , Traumatismos Craneocerebrales/complicaciones , Exoftalmia/etiología , Femenino , Humanos , Arteria Oftálmica/cirugía , Órbita/diagnóstico por imagen , Parálisis/etiología , Inhibidores de Agregación Plaquetaria/uso terapéutico , Ticlopidina/análogos & derivados , Ticlopidina/uso terapéutico , Tomografía Computarizada por Rayos X , Adulto JovenRESUMEN
INTRODUCTION: Clinical use of the Amplatzer vascular plug in the cardiopulmonary and peripheral vasculatures has been described extensively in the literature. We present our initial experience in adapting this device for therapeutic sacrifice of major craniocerebral arteries. MATERIALS AND METHODS: Between July 2007 and November 2008, 8 patients (mean age 59.1 years; range 18 to 82 years) underwent therapeutic occlusion of major craniocerebral arteries using the device, for direct caroticocavernous fistula (1 patient), symptomatic unruptured giant cavernous internal carotid aneurysms (2 patients), and preoperative embolisation before surgical resections of skull base tumours that had encroached upon the internal carotid or vertebral artery (5 patients). The plugs were used alone or in conjunction with detachable platinum coils. The applications of the device, as well as the angiographic and clinical results of the procedures were evaluated. RESULTS: Applications of the plugs were straightforward and successful in all cases, with hermetic occlusions of all target arteries. When used without additional coils, several plugs were deployed in tandem to achieve complete occlusion of the artery. No migration of the device was seen. No patient developed untoward neurological deficits following the procedures, and the 3- and/or 6-month follow-up showed stable results. CONCLUSION: The Amplatzer vascular plug could be a valuable addition to the neurointerventional armamentarium, particularly in therapeutic occlusion of major craniocerebral arteries. Rigidity of the delivery system limits its current use to vessels below the skull base. The potential risk of distal thromboembolism also requires further evaluation.