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A single-chip dual-band 5.15-5.35-GHz and 2.4-2.5-GHz zero-IF transceiver for IEEE 802.11a/b/g WLAN systems is fabricated on a 0.18-µm CMOS technology. It utilizes an innovative architecture including feedback paths that enable digital calibration to help eliminate analog circuit imperfections such as transmit and receive I/Q mismatch. The dual-band receive paths feature a 4.8-dB (3.5-dB) noise figure at 5.25 GHz (2.45 GHz). The corresponding sensitivity at 54 Mb/s operation is -76 dBm for 802.11a and -77 dBm for 802.11g, both referred at the input of the chip. The transmit chain achieves output 1-dB compression at 6 dBm (9 dBm) at 5 GHz (2.4 GHz) operation. Digital calibration helps achieve an error vector magnitude (EVM) of -33 dB (-31 dB) at 5 GHz (2.4 GHz) while transmitting -4 dBm at 54 Mb/s. The die size is 19.3 mm² and the power consumption is 260 mW for the receiver and 320 mW (270 mW) for the transmitter at 5 GHz (2.4 GHz) operation. [ABSTRACT FROM AUTHOR]

Background: Although CO2 is the insufflation gas of choice in laparoscopic procedures, room air is usually used in natural orifice transluminal endoscopic surgery. The aim of the present study was to compare the safety of room air versus CO2 pneumoperitoneum in terms of their effect on the oxidative state, apoptosis and tissue injury of splanchnic organs., Methods: Eighteen Wistar rats were assigned to three groups (n = 6 per group) and were subjected to 8 mm Hg room air (group Pne-Air) or CO2 pneumoperitoneum (group Pne-CO2) or sham operation for 60 min. Forty-five minutes postdeflation, tissue samples were excised from the liver, stomach, ileum and kidneys for reduced glutathione-to-glutathione disulfide (GSH/GSSG) ratio, caspase-8 and caspase-3 and hypoxia-inducible factor-1α (HIF-1α) immunohistochemical assessment and histopathologic examination., Results: GSH/GSSG ratio substantially declined in both pneumoperitoneum groups. No change was noted in HIF-1α expression. Mild upregulation of caspase-8 and caspase-3 was noted in both pneumoperitoneum groups being less pronounced in group Pne-Air. Histopathologic score was increased in all organs studied, but the stomach, in both pneumoperitoneum groups., Conclusion: Pneumoperitoneum established by either room air or CO2 induced substantial oxidative stress, mild apoptosis and mild tissue injury in splanchnic organs. While air pneumoperitoneum conferred a less pronounced apoptotic effect, the oxidative state and histopathologic profile of splanchnic organs did not differ between insufflation gases.

Background: Undifferentiated embryonal sarcoma (UES) of liver is a rare malignant neoplasm, which affects mostly the pediatric population accounting for 13% of pediatric hepatic malignancies, a few cases has been reported in adults., Case Presentation: We report a case of undifferentiated embryonal sarcoma of the liver in a 20-year-old Caucasian male. The patient was referred to us for further investigation after a laparotomy in a district hospital for spontaneous abdominal hemorrhage, which was due to a liver mass. After a through evaluation with computed tomography scan and magnetic resonance imaging of the liver and taking into consideration the previous history of the patient, it was decided to surgically explore the patient. Resection of I-IV and VIII hepatic lobe. Patient developed disseminated intravascular coagulation one day after the surgery and died the next day., Conclusion: It is a rare, highly malignant hepatic neoplasm, affecting almost exclusively the pediatric population. The prognosis is poor but recent evidence has shown that long-term survival is possible after complete surgical resection with or without postoperative chemotherapy.