42 research outputs found

    Duszność spowodowana gruźliczakami powstającymi w rdzeniu przedłużonym w czasie leczenia gruźliczego zapalenia opon mózgowo-rdzeniowych

    Get PDF
    Formation of tuberculoma is a rare response of neurotuberculosis in patients regularly and adequately treated with anti-tuberculous drugs. We report a 13-year-old girl with two tuberculomas which formed in the dorsal part of the medulla oblongata during chemotherapy for tuberculous meningitis. The tuberculomas were both removed via a suboccipital midline approach and were demonstrated by pathological findings but the girl died of cardiac arrest that was thought to be caused by postoperative medulla oblongata oedema. In combination with a literature review, we discuss the clinical features and treatment options of brainstem tuberculomas.Tworzenie się gruźliczaka jest rzadką reakcją w przebiegu właściwie leczonej gruźlicy układu nerwowego. W pracy autorzy opisują przypadek 13-letniej dziewczynki z dwoma gruźliczakami, które utworzyły się w grzbietowej części rdzenia przedłużonego w czasie farmakologicznego leczenia gruźliczego zapalenia opon mózgowo-rdzeniowych. Oba gruźliczaki usunięto z dostępu podpotylicznego w linii środkowej i potwierdzono ich rozpoznanie w badaniu histopatologicznym, ale pacjentka zmarła w wyniku zatrzymania krążenia, przypuszczalnie wskutek pooperacyjnego obrzęku rdzenia przedłużonego. Na podstawie przedstawionego przypadku i przeglądu piśmiennictwa omówiono objawy kliniczne i możliwości leczenia gruźliczaków pnia mózgu

    Novel composite meshes to evaluate their structural property and in vivo biocompatibility for tissue repair

    Get PDF
    Composite meshes of different types have been prepared and used for tissue repair in pelvic floor disorder. An interlocking texture mesh (inter-mesh) and a membrane coated mesh (electro-mesh) have been used based on their structural property and biocompatibility. The proportion of degradation material in inter-mesh (69.6%) is found extremely higher than that of electro-mesh (3.22%), thus leading to higher product weight (65.50±2.31 g/m2) and thickness (0.500±0.025 mm). After 4 weeks of implantation in animal experiment, inter-mesh with surrounding tissues is observed to have higher breaking strength in tensile behavoir and better flexibility. Tissues on inter-mesh are found to grow faster with larger thickness (0.76±0.033 mm). The surface area loss of inter-mesh (2.49±0.25%) is much less than that of electro-mesh (7.49±0.63 %) within the first 2 weeks of implantation. However, the material’s degradation is accelerated after 2 weeks, leading to a higher shrinkage of 13.12±1.48 %

    Novel composite meshes to evaluate their structural property and in vivo biocompatibility for tissue repair

    Get PDF
    404-410Composite meshes of different types have been prepared and used for tissue repair in pelvic floor disorder. An interlocking texture mesh (inter-mesh) and a membrane coated mesh (electro-mesh) have been used based on their structural property and biocompatibility. The proportion of degradation material in inter-mesh (69.6%) is found extremely higher than that of electro-mesh (3.22%), thus leading to higher product weight (65.50±2.31 g/m2) and thickness (0.500±0.025 mm). After 4 weeks of implantation in animal experiment, inter-mesh with surrounding tissues is observed to have higher breaking strength in tensile behavoir and better flexibility. Tissues on inter-mesh are found to grow faster with larger thickness (0.76±0.033 mm). The surface area loss of inter-mesh (2.49±0.25%) is much less than that of electro-mesh (7.49±0.63 %) within the first 2 weeks of implantation. However, the material’s degradation is accelerated after 2 weeks, leading to a higher shrinkage of 13.12±1.48 %

    Optical Multipath RF Self-Interference Cancellation Based on Phase Modulation for Full-Duplex Communication

    Get PDF
    Optical multipath RF self-interference cancellation (SIC) based on phase modulation for full-duplex communication is proposed and demonstrated experimentally. Phase modulation is utilized to convert the RF signal into optical domain, in which the time delay tuning, amplitude tuning and phase inversion for multipath RF SIC are completed. The comprehensive theoretical model of the optical multipath RF SIC system is established, and the factors affecting SIC performance including the time delay, amplitude and phase deviations are analyzed. The experimental results verify the feasibility of the proposed scheme for full-duplex communication with the cancellation depth of 26 dB and 28 dB over 100 MHz at central frequency of 6 GHz and 10 GHz, respectively. A figure of merit of the maximum interference to signal of interest ratio is defined to characterize the SOI recovery capability of optical RF SIC system

    Performance analysis of photonic RF self-interference cancellation for full-duplex communication

    Get PDF
    A photonic RF self-interference cancellation (SIC) scheme for full-duplex communication is proposed and demonstrated experimentally. It is based on phase modulation to convert the RF signal into optical domain. The interference cancellation performance of the photonic RF SIC system under different delay deviation (Δτ) and amplitude deviation (Δα) is analyzed. The cancellation depth of 34.5 dB is measured for 10 GHz signal with bandwidth of 50MHz. According to experimental results, the interference cancellation performance affected by the time delay deviation, the amplitude deviation and the phase response is investigated. The results give a direction for the improvement of system performance

    Controllable sliding transfer of wafer‐size graphene

    Get PDF
    The innovative design of sliding transfer based on a liquid substrate can succinctly transfer high‐quality, wafer‐size, and contamination‐free graphene within a few seconds. Moreover, it can be extended to transfer other 2D materials. The efficient sliding transfer approach can obtain high‐quality and large‐area graphene for fundamental research and industrial applications

    High Linearity Microwave Photonic Up-Conversion System Based on Parallel Dual-Drive Mach–Zehnder Modulators

    No full text
    A large dynamic frequency up-conversion scheme based on parallel dual-drive Mach–Zehnder modulators (DD-MZM) and balance detection is proposed and demonstrated experimentally. By optimizing the distribution ratio of the optical carrier power and the IF signal power between the two DD-MZMs, the third-order intermodulation components in two sub-links cancel each other upon the balanced photodetector. The measured results show that the large spurious-free dynamic range of 112.3 dB·Hz4/5 is obtained for an intermediate frequency signal of 2 GHz up-converted to 18 GHz, which is a 14.8 dB enhancement compared with the traditional carrier suppression double-sideband modulation mixer. The frequency up-conversion performance of the established system for the broadband signal is measured with the results demonstrating the feasibility of the proposed optimization scheme

    Silicon–Organic Hybrid Electro-Optic Modulator and Microwave Photonics Signal Processing Applications

    No full text
    Electro-optic modulator (EOM) is one of the key devices of high-speed optical fiber communication systems and ultra-wideband microwave photonic systems. Silicon–organic hybrid (SOH) integration platform combines the advantages of silicon photonics and organic materials, providing a high electro-optic effect and compact structure for photonic integrated devices. In this paper, we present an SOH-integrated EOM with comprehensive investigation of EOM structure design, silicon waveguide fabrication with Slot structure, on-chip poling of organic electro-optic material, and characterization of EO modulation response. The SOH-integrated EOM is measured with 3 dB bandwidth of over 50 GHz and half-wave voltage length product of 0.26 V·cm. Furthermore, we demonstrate a microwave photonics phase shifter by using the fabricated SOH-integrated dual parallel Mach–Zehnder modulator. The phase shift range of 410° is completed from 8 GHz to 26 GHz with a power consumption of less than 38 mW
    corecore