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Due to the proliferation of frequency bands that need to be supported in wireless standards, such as LTE, GSM, 5G, etc., modern wireless transceiver designs rely on numerous off-chip SAW/BAW filters and many on-chip LC tanks, which are typically not very tunable. On the receiver end, this is because wireless signals typically possess vastly different strengths, and such large signal strength differences necessitate the receiver front-ends to be low-noise and linear, while providing sharp filtering. Hence, conventional approaches resort to passive off- and on-chip band-pass filters. Not only are these filters bulky, but they generally have fixed bandwidths and center frequencies, therefore a number of them are needed, occupying a lot of PCB and chip area to cover multiple bands. Consequently, it has been of significant interest in recent years to explore high-programmability SAW/BAW-less transceivers for emerging software-defined and cognitive radio applications. However, without the pre-filtering provided by SAW/BAW filters, such receivers face great challenges in providing sufficient performance in the aforementioned aspects simultaneously. Some recent approaches include N-path filters (NPFs), mixer-first receivers, and discrete-time (DT) charge-domain signal processing. They have demonstrated some level of programmability, while providing reasonably good performance, yet their overall performance has not reached that of their counterparts using off-chip SAW/BAW filters and/or on-chip LC filters.In this work, we explore the newly developed filtering-by-aliasing (FA) technique to build receiver front-ends using periodically time-varying (PTV) circuits. The FA technique essentially realizes sharp baseband analog FIR filtering. In conjunction with a mixer, the FA receivers offer one of the sharpest band-pass filters achieved with CMOS technologies to date and extremely high programmability. However, they also face a few problems, including relatively high noise, moderate linearity, sensitivity to parasitics at RF, and residual aliases that cannot be further filtered. They limit the ultimate dynamic range that FA receivers can achieve, and prevent wider adoption of FA receivers. This research looks into enabling techniques to enhance the dynamic range of FA receiver front-ends in order to make them more practical. A technique based on PTV noise cancellation was proposed to effectively lower the noise figure (NF) of the receiver, while maintaining the FA sharp filtering. Measurement results show an improvement of about 3 dB on NF, while simultaneously achieving 67-dB stopband rejection with a transition bandwidth of 4� the RF bandwidth. In conjunction with an up-front NPF, an out-of-band IIP3 of +18 dBm and a blocker 1-dB compression point of +9 dBm have been demonstrated. Moreover, an innovative slice-based FA architecture with all switches moved inside the feedback network has been proposed for FA receivers in this work to provide support for carrier aggregation and improve linearity. The fabricated prototype in 28-nm CMOS demonstrated two-channel concurrent reception with filters that achieve 50-dB stopband rejection with a transition bandwidth of 3.2� the RF bandwidth. It has also shown +35-dBm IIP3 and +12-dBm blocker 1-dB compression point with a supply voltage of only 0.9 V, whereas a low LO leakage of -81 dBm was also demonstrated. Further, a residual alias cancellation technique for FA receivers has been proposed and demonstrated on a dual-channel FA receiver. With measured frequency responses of the receiver, digital baseband filters are designed to cancel the residual aliases. Built in MATLAB, the proposed alias cancellation algorithm achieves about 15-dB alias suppression on measured data in addition to the analog FA filtering.

Wei Wang,&ast; Fei Teng,&ast; Shi Bu, Wei Xu, Qing-Chun Cai, Yue-Quan Jiang, Zhi-Qiang Wang Key Laboratory for Biorheological Science and Technology of Ministry of Education (Chongqing University), Chongqing University Cancer Hospital, Chongqing, 400030, China&ast;These authors contributed equally to this workCorrespondence: Yue-Quan Jiang; Zhi-Qiang Wang, Key Laboratory for Biorheological Science and Technology of Ministry of Education (Chongqing University), Chongqing University Cancer Hospital, No. 181 of Hanyu Road, Shapingba District, Chongqing, 400030, China, Tel +86 13708335256 ; +86 15215023098, Email jiangyuequanjyq1@126.com; wangzhiqiangwzq9@126.comObjective: This study aimed to design a nomogram survival prediction by means of the figures retrieved from the Surveillance, Epidemiology, and End Results (SEER) source bank, and to predict the overall survival (OS) of patients with stage IIA non-small cell lung cancer (NSCLC) after surgery.Methods: Data for 4511 patients who had been diagnosed with postoperative stage IIA NSCLC were collected from the SEER databank, while information on 528 patients was acquired from the Chongqing University Cancer Hospital for the external validation cohort. The independent risk factors that affected the prognosis were identified using a multivariate Cox proportional hazards regression model (also used to conduct a nomogram). A survival analysis between the low- and the high-risk groups was performed using the Kaplan–Meier method. Furthermore, a subgroup analysis was conducted of the two groups using the Kaplan–Meier method to determine whether the patients had received adjuvant chemotherapy.Results: The following five variables were integrated into the nomogram: sex (female: HR 1.73, 95% CI 0.64– 0.83), age (≥ 60: HR 1.61, 95% CI 1.39– 1.87), differentiation grade (grade II: HR 2.19, 95% CI 1.66– 2.88; grade III: HR 2.65, 95% CI 2.00– 3.51; grade IV: HR 3.17, 95% CI 1.99– 5.03), surgery (lobectomy: HR 0.72, 95% CI 0.59– 0.86), and lymph node resection (> 12: HR 0.82, 95% CI 0.70– 0.96). Furthermore, the patients selected were categorized into high- and low-risk groups. The OS rate was significantly lower in the high-risk group than in the low-risk group (P < 0.001). Finally, adjuvant chemotherapy was highly correlated with OS in the high-risk set (P = 0.035); however, adjuvant chemotherapy was not related to OS in the low-risk set.Conclusion: A nomogram was created as a reliable, convenient scheme that could predict OS, and it was determined that the high-risk feature patients identified by the nomogram gained benefits from adjuvant chemotherapy.Keywords: nomogram, stage IIA non-small cell lung cancer, adjuvant chemotherapy, OS prediction

In this paper, three types of wire-plate electrostatic precipitators with expanded-shrunk spoilers (ESP-ESSs) were proposed. The influences of different geometric characteristics and arrangements of the expanded-shrunk spoilers (ESSs) on the electric field intensity, airflow field, particle trajectory, and collection efficiency were investigated by experiment and numerical simulation. The ESP-ESSs was compared with ESP with parallel plates (ESP-PP). The numerical results were relatively in agreement with the experimental data. The maximum error was 6.5%. The results showed that with the increase of the ESS height, the electric field intensity increased. The ESSs could generate low-velocity vortices contributing to extend the retention time of particles, which was conducive to particle collection. In general, the collection efficiency of the ESP-ESS was superior to the ESP-PP, but there was no advantage for fine particles at high inlet gas velocity and low applied voltage.

Salt separation experiments are selectively conducted for the high-salt wastewater of lead-acid batteries. Two useful products, sodium sulfate and sodium chloride, are obtained by evaporation crystallization. The experiment investigates the effect of different temperatures and concentration ratios on the precipitation content and purity of sodium sulfate and sodium chloride during the evaporation and concentration of wastewater, and explores the optimal concentration ratio and temperature for the separation and purification of sodium sulfate. Moreover, the experimental data are fitted with the mathematical model. The results show that for wastewater with 0.5 L chloride ion concentration of 17.9 g/L and sulfate ion concentration of 188.4 g/L, sodium sulfate with 98% purity can be obtained when the concentration ratio is 1.66. When the concentration ratio is in the range of 1.66–2, the precipitation of sodium sulfate is more than 25.76 g in the range of 50 °C–90 °C. When the evaporation temperature is stable at 60 °C and the concentration ratio is from 1.46 to 3.5, both the yield and purity of sodium sulfate crystals are improved, the precipitation of sodium sulfate is up to 88.63 g and the purity is up to 98%.