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1.
Sensors (Basel) ; 22(14)2022 Jul 21.
Article in English | MEDLINE | ID: mdl-35891136

ABSTRACT

This paper presents a radio frequency (RF) triple pole triple throw 3P3T cross antenna switch for cellular mobile devices. The negative biasing scheme was applied to improve the power-handling capability and linearity of the switch by increasing the maximum tolerable voltage drop across the drain and source and reverse biasing the parasitic junction diodes. To avoid signal reflection through the antenna in off-state, all the antenna ports were equipped with 50-ohm termination to provide the pull-down path. Considering the simultaneous operation of antenna ports in different switch cases, the presented T-type pull-down path demonstrated improvement of isolation by over 15 dB. Using stacked switches, the 3P3T handled the input power level of over 35 dBm. The chip was manufactured in 65 nm complementary metal oxide semiconductor (CMOS) silicon on insulator (SOI) technology with a die size of 790 × 730 µm. The proposed structure achieved insertion loss, isolation, and voltage standing wave ratio (VSWR) of less than -0.9 dB, -40 dB, and 1.6, respectively, when the input signal was 3.8 GHz. The measured results prove the implemented switch shows the second and third harmonic distortion performances of less than -60 dBm when the input power level and frequency are 25 dBm and 3.8 GHz, respectively.


Subject(s)
Radio Waves , Semiconductors , Computers, Handheld , Silicon
2.
Sensors (Basel) ; 22(11)2022 May 26.
Article in English | MEDLINE | ID: mdl-35684660

ABSTRACT

This paper presents a multi-gain radio frequency (RF) front-end low noise amplifier (LNA) utilizing a multi-core based on the source degeneration topology. The LNA can cover a wide range of input and output frequency matching by using a receiver (RX) switch at the input and a capacitor bank at the output of the LNA. In the proposed architecture here, to avoid the saturation of RX chain, 12 gain steps including positive, 0 dB, and negative power gains are controlled by a mobile industry processor interface (MIPI). The multi-core architecture offers the ability to control the power consumption over different gain steps. In order to avoid the phase discontinuity, the negative gain steps are provided using an active amplification and T-type attenuation path that keeps the phase discontinuity below ±5 degrees between two adjacent power gain steps. Using the multi-core structure, the power consumption is optimized in different power gains. The structure is enhanced with the adaptive variable cores and reactance parameters to maintain different power consumption for different gain steps and remain the output matching in an acceptable operating range. Furthermore, auxiliary linearization circuitries are added to improve the input third intercept point (IIP3) performance of the LNA. The chip is fabricated in 65 nm complementary metal-oxide semiconductor (CMOS) silicon on insulator (SOI) process and the die area is 0.308 mm2. The proposed architecture achieves the IIP3 performance of -10.2 dBm and 8.6 dBm in the highest and lowest power gains, which are 20.5 dB and -11 dB, respectively. It offers the noise figure (NF) performance of 1.15 dB in the highest power gain while it reaches 14 dB when the power gain is -11 dB. The LNA consumes 16.8 mA and 1.33 mA current from a 1 V power supply that is provided by an on-chip low-dropout (LDO) when it operates at the highest and lowest gains, respectively.

3.
BMC Med Inform Decis Mak ; 20(1): 241, 2020 09 22.
Article in English | MEDLINE | ID: mdl-32962726

ABSTRACT

BACKGROUND: Clinical Decision Support Systems (CDSSs) have recently attracted attention as a method for minimizing medical errors. Existing CDSSs are limited in that they do not reflect actual data. To overcome this limitation, we propose a CDSS based on deep learning. METHODS: We propose the Colorectal Cancer Chemotherapy Recommender (C3R), which is a deep learning-based chemotherapy recommendation model. Our model improves on existing CDSSs in which data-based decision making is not well supported. C3R is configured to study the clinical data collected at the Gachon Gil Medical Center and to recommend appropriate chemotherapy based on the data. To validate the model, we compared the treatment concordance rate with the National Comprehensive Cancer Network (NCCN) Guidelines, a representative set of cancer treatment guidelines, and with the results of the Gachon Gil Medical Center's Colorectal Cancer Treatment Protocol (GCCTP). RESULTS: For the C3R model, the treatment concordance rates with the NCCN guidelines were 70.5% for Top-1 Accuracy and 84% for Top-2 Accuracy. The treatment concordance rates with the GCCTP were 57.9% for Top-1 Accuracy and 77.8% for Top-2 Accuracy. CONCLUSIONS: This model is significant, i.e., it is the first colon cancer treatment clinical decision support system in Korea that reflects actual data. In the future, if sufficient data can be secured through cooperation among multiple organizations, more reliable results can be obtained.


Subject(s)
Colonic Neoplasms , Colorectal Neoplasms , Decision Support Systems, Clinical , Deep Learning , Colorectal Neoplasms/drug therapy , Humans , Republic of Korea
4.
J Med Food ; 13(1): 6-12, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20136430

ABSTRACT

The anticancer effects of chitosan-added kimchi were investigated by using an in vitro cellular system with HT-29 human colon carcinoma cells. Two different kinds of chitosan-soluble chitosan with a 90% degree of deacetylation and 3 cps viscosity and nonsoluble chitosan with a 95% degree of deacetylation and 22 cps viscosity-were used as sub-ingredients to increase anticancer effects of kimchi. The soluble chitosan-added kimchi (SK) and nonsoluble chitosan-added kimchi (NK) were stronger growth inhibitors in HT-29 cells than the control kimchi (CK) according to the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and the growth inhibition test. Treatment with SK and NK induced apoptosis, as determined by 4,6-diamidino-2-phenylindole staining, and resulted in the up-regulation of Bax expression and down-regulation of Bcl-2, cIAP-1, cellular inhibitor of apoptosis-2, cyclooxygenase-2, inhibitory nitric oxide synthase, and nuclear factor kappaB (NF-kappaB) expressions when compared to CK. The antiproliferative and anti-apoptotic effects appeared to be more pronounced in the cells treated with NK. The antiproliferative effects of the chitosan-added kimchi appeared to be associated with the induction of apoptosis through NF-kappaB or an NF-kappaB-dependent pathway. These results suggest that chitosan has potential to be a valuable active ingredient in functional kimchi products with anticancer effects.


Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma/drug therapy , Cell Proliferation/drug effects , Chitosan/pharmacology , Colonic Neoplasms/drug therapy , Vegetables , Acetylation , Antineoplastic Agents/therapeutic use , Apoptosis/drug effects , Carcinoma/metabolism , Chitosan/therapeutic use , Colonic Neoplasms/metabolism , Cyclooxygenase 2/genetics , Cyclooxygenase 2/metabolism , Diet , Fermentation , Food, Fortified , Gene Expression , HT29 Cells , Humans , Inhibitor of Apoptosis Proteins/genetics , Inhibitor of Apoptosis Proteins/metabolism , NF-kappa B/genetics , NF-kappa B/metabolism , Nitric Oxide Synthase/genetics , Nitric Oxide Synthase/metabolism , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , Viscosity , bcl-2-Associated X Protein/genetics , bcl-2-Associated X Protein/metabolism
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