53 research outputs found
Demonstration of M-QAM OFDM bidirectional 60/25 GHz transmission over 10 km Fiber, 100 m FSO and 2 m radio seamless heterogeneous fronthaul link
[EN] In this paper, we demonstrate the experimental transmission of 16-and 64-quadrature amplitude modulation (QAM) Long Term Evolution -Orthogonal Frequency Division Multiplexing (LTE-OFDM) signals by using mil-limetre wave frequencies at 60 GHz and 25 GHz for downlink and uplink, respectively, over a heterogeneous optical fronthaul infrastructure. A directly modulated laser was employed for both links, which enables the cost-effective full-duplex system proposal. The bidirectional link consists of a 10 km of single mode fiber, a 100 m long free space optics channel and 2 m long wireless radio link, which brings flexibility for future wireless networks. The error vector magnitude (EVM) parameter is measured for a range of the received optical and electrical power as well as the signal-to-noise ratio. A comprehensive estimation of penalty factors in the different network segments is presented. The successful transmission over the whole proposed network with the EVM below the required limit of 9 % for 64-QAM with 20 MHz bandwidth is experimentally demonstrated for the received optical power of-2.7 dBm and-1 dBm for the downlink and uplink, respectively.The research has been supported by the CTU in Prague SGS20/166/OHK3/3T/13, project from Ministry of Industry and Trade in Czech Republic (FV40089) and within COST action CA19111 (NEWFOCUS) . It has also been funded by the regional project from Generalitat Valenciana PROMETEO 2021/015 and Grant RTI2018-101658-B-I00 FOCAL by MCIN/AEI/10.13039/501100011033 and ERDF "A way of making Europe".Vallejo, L.; Ortega Tamarit, B.; Mora Almerich, J.; Nguyen, D.; Guerra, C.; Bohata, J.; Spacil, J.... (2023). Demonstration of M-QAM OFDM bidirectional 60/25 GHz transmission over 10 km Fiber, 100 m FSO and 2 m radio seamless heterogeneous fronthaul link. Optical Fiber Technology. 77. https://doi.org/10.1016/j.yofte.2022.1031617
Laparoscopic repair of perforated cecal diverticulitis
We present a case of cecal diverticulitis in a 15-year old Romani- girl, who underwent laparoscopy because of clinical suspicion of acute appendicitis. Intraoperatively a perforated cecal diverticulum next to a normal, uninflammated appendix was seen. To avoid ileocecectomy on a child, we excised the diverticulum and performed a laparoscopic suture repair. In addition an appendectomy was carried out. The patient recovered well and was discharged on the sixth post-operative day. This case report shows that laparoscopic diverticulectomy is a feasible alternative to a much more invasive open/laparoscopic ileocecectomy which carries significant long-term morbidity because of the loss of the valve of Bauhin. Keywords: Cecal diverticulitis, Laparoscopic repair, Diverticulectomy, Pediatric patien
Pre-Assessment of Radiated Fields from Small Electronic Submodules
A novel approach to the evaluation of electromagnetic fields radiated from electronic devices by using a small shielded box is presented. Several EMC problems can be identified by employing the computations of a Radiated Model device, such as the model of the Submodule-on-Motherboard structure described here. The combination of a numerical approach, through a validation model and measurements, must be done during the design phase in multiple iterative loops to minimize the risk of non-compliance of the final qualification process. This novel combined approach requires little investment and is highly efficient for industrial applications
Simultaneous liquid chromatographic determination of metals and organic compounds in pharmaceutical and food-supplement formulations using evaporative light scattering detection
A novel method for the non-derivatization liquid chromatographic determination of metals (potassium, aluminium, calcium and magnesium) and organic compounds (ascorbate and aspartate) was developed and validated based on evaporative light scattering detection (ELSD). Separation of calcium, magnesium and aluminium was achieved by the cation exchange column Dionex CS-14 and an aqueous TFA mobile phase according to the following time program: 0-6 min TFA 0.96 mL L-1, 6-7 min linear gradient from TFA 0.96-6.4 mL L-1. Separation of potassium, magnesium and aspartate was achieved by the lipophilic C18 Waters Spherisorb column and isocratic aqueous 0.2 mL L-1 TFA mobile phase. Separation of sodium, magnesium, ascorbate and citrate was also achieved by the C18 analytical column, according to the following elution program: 0-2.5 min aqueous nonafluoropentanoic acid (NFPA) 0.5 mL L-1; 2.5-3.5 min linear gradient from 0.5 mL L-1 NFPA to 1.0 mL L-1 TFA. In all cases, evaporation temperature was 70 °C, pressure of the nebulizing gas (nitrogen) 3.5 bar, gain 11 and the flow rate 1.0 mL min-1. Resolution among calcium and magnesium was 1.8, while for all other separations was ≥3.2. Double logarithmic calibration curves were obtained within various ranges from 3-24 to 34-132 μg mL-1, and with good correlation (r > 0.996). Asymmetry factor ranged from 0.9 to 1.9 and limit of detection from 1.3 (magnesium) to 17 μg mL-1 (ascorbate). The developed method was applied for the assay of potassium, magnesium, calcium, aluminium, aspartate and ascorbate in pharmaceuticals and food-supplements. The accuracy of the method was evaluated using spiked samples (%recovery 95-105%, %R.S.D. < 2) and the absence of constant or proportional errors was confirmed by dilution experiments. © 2006 Elsevier B.V. All rights reserved
Simultaneous liquid chromatographic determination of metals and organic compounds in pharmaceutical and food-supplement formulations using evaporative light scattering detection
A novel method for the non-derivatization liquid chromatographic determination of metals (potassium, aluminium, calcium and magnesium) and organic compounds (ascorbate and aspartate) was developed and validated based on evaporative light scattering detection (ELSD). Separation of calcium, magnesium and aluminium was achieved by the cation exchange column Dionex CS-14 and an aqueous TFA mobile phase according to the following time program: 0-6 min TFA 0.96 mL L-1, 6-7 min linear gradient from TFA 0.96-6.4 mL L-1. Separation of potassium, magnesium and aspartate was achieved by the lipophilic C18 Waters Spherisorb column and isocratic aqueous 0.2 mL L-1 TFA mobile phase. Separation of sodium, magnesium, ascorbate and citrate was also achieved by the C18 analytical column, according to the following elution program: 0-2.5 min aqueous nonafluoropentanoic acid (NFPA) 0.5 mL L-1; 2.5-3.5 min linear gradient from 0.5 mL L-1 NFPA to 1.0 mL L-1 TFA. In all cases, evaporation temperature was 70 °C, pressure of the nebulizing gas (nitrogen) 3.5 bar, gain 11 and the flow rate 1.0 mL min-1. Resolution among calcium and magnesium was 1.8, while for all other separations was ≥3.2. Double logarithmic calibration curves were obtained within various ranges from 3-24 to 34-132 μg mL-1, and with good correlation (r > 0.996). Asymmetry factor ranged from 0.9 to 1.9 and limit of detection from 1.3 (magnesium) to 17 μg mL-1 (ascorbate). The developed method was applied for the assay of potassium, magnesium, calcium, aluminium, aspartate and ascorbate in pharmaceuticals and food-supplements. The accuracy of the method was evaluated using spiked samples (%recovery 95-105%, %R.S.D. < 2) and the absence of constant or proportional errors was confirmed by dilution experiments. © 2006 Elsevier B.V. All rights reserved
Closure to “Discussion of ‘The Transport of Chromium in Cr2 O 3 Scales in Sulfidizing Environments’ [G. Romeo, H. S. Spacil, and W. J. Pasko (pp. 1329–1333, Vol. 122, No. 10)]”
Distinguishing the cyanobacterial neurotoxin beta-N-methylamino-L-alanine (BMAA) from its structural isomer 2,4-diaminobutyric acid (2,4-DAB)
The Determination of Chemical Diffusivity in Cobaltous Oxide by Means of Electrical Conductivity
Pilot study of newborn screening for six lysosomal storage diseases using Tandem Mass Spectrometry
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