Broadband active load-modulation power amplifiers (PAs) are effective to enable multistandard wireless communication systems with high dynamic-range wideband signals and high energy efficiency. ...Traditional Doherty or outphasing PA architectures support their classic active load-modulation operations but, however, exhibit limited carrier bandwidth. We propose a broadband active load-modulation PA architecture with multifrequency role-exchange coupler-based Doherty amplifier (MF-CDA) operations to cover over-an-octave bandwidth. A proof-of-concept PA has been designed and fabricated in a 45-nm RF CMOS SOI process, which achieves a peak PAE of 41.88%-19.4% with <inline-formula> <tex-math notation="LaTeX">P_{\mathrm {sat}} </tex-math></inline-formula> of over 22.66-19.53 dBm from 26 to 60 GHz. The PA also achieves a 33.75%-10.2% 6-dB PBO efficiency with its best 1.8<inline-formula> <tex-math notation="LaTeX">\times </tex-math></inline-formula> efficiency enhancement over an ideal Class-B PA. Using a single-carrier 64-QAM signal with 0.8-3 GSym/S (4.8-18 Gb/s), the PA supports an average <inline-formula> <tex-math notation="LaTeX">P_{\mathrm {out}} </tex-math></inline-formula> of 15.8-11.3 dBm with an average PAE of 23.8%-8.5% at −23-dB rms EVM over the entire bandwidth. For a single-carrier 16-QAM signal with 1-2.5 GSym/S (4-10 Gb/s), the PA achieves an average <inline-formula> <tex-math notation="LaTeX">P_{\mathrm {out}} </tex-math></inline-formula> of 18.7-15.6 dBm with an average PAE of 34%-14.8% at <inline-formula> <tex-math notation="LaTeX">>- </tex-math></inline-formula>20-dB rms EVM over the bandwidth. The PA also supports 5G NR modulation using 5G new radio (NR) FR2 200 MHz 1-CC 64-QAM signals, achieving 16.54%-5.2% average PAE at 12.25-9.34 dBm and average <inline-formula> <tex-math notation="LaTeX">P_{\mathrm {out}} </tex-math></inline-formula> with an rms EVM of −24 dB over 26-60 GHz.
Subdistal appendages (sDAPs) are centriolar elements that are observed proximal to the distal appendages (DAPs) in vertebrates. Despite the obvious presence of sDAPs, structural and functional ...understanding of them remains elusive. Here, by combining super-resolved localization analysis and CRISPR-Cas9 genetic perturbation, we find that although DAPs and sDAPs are primarily responsible for distinct functions in ciliogenesis and microtubule anchoring, respectively, the presence of one element actually affects the positioning of the other. Specifically, we find dual layers of both ODF2 and CEP89, where their localizations are differentially regulated by DAP and sDAP integrity. DAP depletion relaxes longitudinal occupancy of sDAP protein ninein to cover the DAP region, implying a role of DAPs in sDAP positioning. Removing sDAPs alter the distal border of centrosomal γ-tubulins, illustrating a new role of sDAPs. Together, our results provide an architectural framework for sDAPs that sheds light on functional understanding, surprisingly revealing coupling between DAPs and sDAPs.
Antenna load impedance variations typically cause significant power amplifier (PA) performance degradation, including output power, large-signal linearity, and peak/average PA efficiency, which are ...especially critical for modern millimeter-wave (mm-Wave) communications with spectrally efficient complex modulations. To address this problem, we propose a reconfigurable hybrid series/parallel Doherty PA with a 90°-coupler-based active load modulation network. By reconfiguring the series/parallel Doherty operation modes, the strengths of the Main/Auxiliary PAs, and their relative phase, linear output power (<inline-formula> <tex-math notation="LaTeX">{\mathrm {OP}}_{1{\mathrm{ ~dB}}} </tex-math></inline-formula>), as well as peak output power (<inline-formula> <tex-math notation="LaTeX">P_{\mathrm {sat}} </tex-math></inline-formula>) and energy efficiency (PAE peak and <inline-formula> <tex-math notation="LaTeX">{\mathrm {PAE}}_{1{\mathrm{ ~dB}}} </tex-math></inline-formula>) of the PA can be largely restored under full-span 360° antenna impedance variations. The theoretical analysis and design guidelines are both presented in this article. As a proof of concept, a 39-GHz reconfigurable hybrid series/parallel Doherty PA is fabricated in the Global Foundries 45-nm RF CMOS silicon on insulator (SOI) process with a 2-V PA supply and 1-V driver supply. At 39 GHz, the PA achieves a 33.3% peak power-added efficiency (PAE) at 20.8-dBm <inline-formula> <tex-math notation="LaTeX">P_{\mathrm {sat}} </tex-math></inline-formula> and 32.2% <inline-formula> <tex-math notation="LaTeX">{\mathrm {PAE}}_{1{\mathrm{ ~dB}}} </tex-math></inline-formula> at 20.2-dBm <inline-formula> <tex-math notation="LaTeX">{\mathrm {OP}}_{1{\mathrm{ ~dB}}} </tex-math></inline-formula> at a nominal 50-<inline-formula> <tex-math notation="LaTeX">\Omega </tex-math></inline-formula> load. The reconfigured PA demonstrates an 18.5-19.12-dBm <inline-formula> <tex-math notation="LaTeX">{\mathrm {OP}}_{1{\mathrm{ ~dB}}} </tex-math></inline-formula> with a high <inline-formula> <tex-math notation="LaTeX">{\mathrm {PAE}}_{1{\mathrm{ ~dB}}} </tex-math></inline-formula> of 20.6%-25.3% at 3:1 antenna voltage standing wave ratio (VSWR) over 360° angles. The PA achieves an rms error vector magnitude (EVM) of −23.6 dB/−22.8 dB/−23.1 dB at an average <inline-formula> <tex-math notation="LaTeX">P_{\mathrm {out}} </tex-math></inline-formula> of 13.8 dBm/12.2 dBm/11.5 dBm with 100 MSym/S/500 MSym/S/1 GSym/S single-carrier 64-quadratic-amplitude modulation (QAM) signal, respectively, at a nominal load of 50 <inline-formula> <tex-math notation="LaTeX">\Omega </tex-math></inline-formula>. A greater-than 11.2-dBm average <inline-formula> <tex-math notation="LaTeX">P_{\mathrm {out}} </tex-math></inline-formula> is achieved at an rms EVM of −24 dB under a full-span 3:1 antenna VSWR with a 100-MSym/S 64-QAM signal.
This article presents an extremely broadband 24.5-43.5 GHz receiver (RX) achieving 32-56-dB instantaneous full-band image rejection (IR), which supports multiple major mm-Wave 5G bands at ...24.5/28/37/39/43 GHz. A compact transformer-based I/Q network (0.14 mm 2 ) is proposed to generate high-precision LO I/Q signals at millimeter-wave (mm-Wave) and provide built-in load impedance up-transformation for passive voltage amplification, boosting the LO swing for a higher RX conversion gain (CG). The high-quality differential I/Q generation is measured with phase/amplitude variation less than ±1.8°/±0.15 dB over an instantaneous wide bandwidth of 25-50 GHz without any calibration or switching/tunable elements. The RX is measured with a peak 35.2-dB CG and 18-dB gain tuning to accommodate complex EM environments. The RX modulation tests successfully demonstrate receiving 18-Gb/s 64-QAM and 14.4-Gb/s 256-QAM signals. In addition, the RX is tested with concurrent injection of a desired signal and an image, while the image uses the same wideband modulation scheme and data rate as the desired signal. The RX successfully rejects the wideband images and receives the desired signals of 12-Gb/s 64-QAM with -27.6-dB EVM and 8-Gb/s 256-QAM with -33.47-dB EVM. To the best of our knowledge, this article presents the first CMOS RX front end that covers 24.5-43.5-GHz mm-Wave 5G bands and supports instantaneous full-band IR with no calibration, switching/tuning elements, or external controls, enabling future wideband low-latency 5G MIMOs.
Joint sensing-and-communication is envisioned to play a major role in emerging mm-Wave wireless systems to perform rapid tracking of wireless nodes for reliable wireless communication and ubiquitous ...distributed sensing. Phased arrays are essential to realize high array gains and enhance the communication distance. However, their pencil sharp beams require precise localization and tracking of wireless nodes to maintain beam alignment and reliable communication, especially in mobile wireless links. In parallel, array-based mm-Wave radars require large arrays for precise angular resolution that is fundamentally limited by the form factor and power consumption of the radar systems. We propose a frequency modulated array (FMA) transmitter (Tx) to convert locations/positions to timing information, which supports dual-modes for joint sensing-and-communication: rapid and precise full field-of-view (FoV) receiver (Rx) localization in the Tx/Rx localization mode for wireless communication and target angular detection in its radar mode. Exploiting its unique joint space-time-frequency dependent signals, the FMA distinguishes spatial signatures far below its array 3-dB beamwidth, i.e., achieving super-resolution and can simultaneously localize multiple Rx nodes or detect multiple targets in "one-shot." Moreover, FMA only adds minimal circuit/computation overhead on traditional multi-in multi-out (MIMO) arrays. A proof-of-concept 28-GHz four-element multi-mode FMA Tx array is implemented in a 45 nm CMOS silicon on insulator (SOI) process. Over-the-air (OTA) measurements with Rx nodes in the communication-mode or reflectors in radar-mode demonstrate the four-element FMA Tx array operations and achieve a full-FoV coverage with <2°-4° accuracy in angular localization with a 10 ns timing resolution (i.e., 100 MHz digital clock in Rx). Sensing aided communication is demonstrated to create sharp and secure constellation decomposition array (CDA) 64 quadratic-amplitude modulation (QAM) beams toward target Rx at low rms error vector magnitude (EVM) of < 5.33% using the sensed data from FMA based Rx localization scheme.
Lin28, a key factor for cellular reprogramming and generation of induced pluripotent stem cell (iPSC), makes a critical contribution to tumorigenicity by suppressing Let-7. However, it is unclear ...whether Lin28 is involved in regulating cancer stem-like cells (CSC), including in oral squamous carcinoma cells (OSCC). In this study, we demonstrate a correlation between high levels of Lin28B, Oct4, and Sox2, and a high percentage of CD44(+)ALDH1(+) CSC in OSCC. Ectopic Lin28B expression in CD44(-)ALDH1(-)/OSCC cells was sufficient to enhance Oct4/Sox2 expression and CSC properties, whereas Let7 co-overexpression effectively reversed these phenomena. We identified ARID3B and HMGA2 as downstream effectors of Lin28B/Let7 signaling in regulating endogenous Oct4 and Sox2 expression. Let7 targeted the 3' untranslated region of ARID3B and HMGA2 and suppressed their expression, whereas ARID3B and HMGA2 increased the transcription of Oct4 and Sox2, respectively, through promoter binding. Chromatin immunoprecipitation assays revealed a direct association between ARID3B and a specific ARID3B-binding sequence in the Oct4 promoter. Notably, by modulating Oct4/Sox2 expression, the Lin28B-Let7 pathway not only regulated stemness properties in OSCC but also determined the efficiency by which normal human oral keratinocytes could be reprogrammed to iPSC. Clinically, a Lin28B(high)-Let7(low) expression pattern was highly correlated with high levels of ARID3B, HMGA2, OCT4, and SOX2 expression in OSCC specimens. Taken together, our results show how Lin28B/Let7 regulates key cancer stem-like properties in oral squamous cancers.
The understanding for the impact of petrochemical pollutants exposure on renal functions is limited.
Our study examined the associations between renal functions and pollutants exposure in adult ...residents living in the vicinity of a petrochemical industry.
We recruited 2069 adult residents near a big petrochemical complex in Taiwan in 2009–2012, and they were categorized into high exposure (HE) and low exposure (LE) groups based on their address to source by 10 km radius. Study subjects were measured the urinary levels of arsenic, cadmium, mercury, thallium, and 1-hydroxypyrene (1-OHP). The estimated glomerular filtration rate (eGFR) was calculated using the Taiwanese Chronic Kidney Disease Epidemiology Collaboration equation, and the chronic kidney disease (CKD) prevalence and risks were defined according to KDIGO 2012 guidelines. Adjusted generalized linear and logistic regression models were applied to evaluate the associations between petrochemical exposure and renal functions.
Subjects in the HE areas had significantly lower eGFR, higher CKD prevalence, and higher levels of urinary arsenic, cadmium, mercury, thallium and 1-OHP. The closer to complex and high exposure group of study subjects were significantly associated with the decrease in eGFR, higher ORs for CKD and high-intermediate risk of CKD. In addition, the study subjects who had two-fold urinary arsenic and 1-OHP levels were significantly with decreased 0.68 and 0.49 ml/min/1.73 m2 of eGFR, respectively.
Residing closer and higher arsenic and polycyclic aromatic hydrocarbon exposure were associated with the renal impairment and risks of CKD among the residential population near the petrochemical industry.
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•Renal effect and risks of CKD among residents near the petrochemical industry.•Residential exposure from petrochemical complex observed by biomonitoring.•Higher arsenic and PAHs exposure associated with adverse renal function.
Background & Aims Some cancer cells have activities that are similar to those of stem cells from normal tissues, and cell dedifferentiation correlates with poor prognosis. Little is known about the ...mechanisms that regulate the stem cell–like features of cancer cells; we investigated genes associated with stem cell–like features of colorectal cancer (CRC) cells. Methods We isolated colonospheres from primary CRC tissues and cell lines and characterized their gene expression patterns by microarray analysis. We also investigated the biological features of the colonosphere cells. Results Expanded CRC colonospheres contained cells that expressed high levels of CD44 and CD166, which are markers of colon cancer stem cells, and had many features of cancer stem cells, including chemoresistance and radioresistance, the ability to initiate tumor formation, and activation of epithelial-mesenchymal transition (EMT). SNAIL, an activator of EMT, was expressed at high levels by CRC colonospheres. Overexpression of Snail in CRC cells induced most properties of colonospheres, including cell dedifferentiation. Two hundred twenty-seven SNAIL-activated genes were up-regulated in colonospheres; gene regulatory networks centered around interleukin (IL)-8 and JUN. Blocking IL-8 expression or activity disrupted SNAIL-induced stem cell–like features of colonospheres. We observed that SNAIL activated the expression of IL8 by direct binding to its E3/E4 E-boxes. In CRC tissues, SNAIL and IL-8 were coexpressed with the stem cell marker CD44 but not with CD133 or CD24. Conclusions In human CRC tissues, SNAIL regulates expression of IL-8 and other genes to induce cancer stem cell activities. Strategies that disrupt this pathway might be developed to block tumor formation by cancer stem cells.
We study the loop-induced circularly polarized gamma rays from dark matter annihilation using the effective dark matter theory approach. Both neutral scalar and fermionic dark matter annihilating ...into monochromatic diphoton and Z-photon final states are considered. To generate the circular polarization asymmetry, P and CP symmetries must be violated in the couplings between dark matter and Standard Model fermions inside the loop with non-vanishing Cutkosky cut. The asymmetry can be sizable especially for Z-photon final state for which asymmetry of nearly 90% can be reached. We discuss the prospect for detecting the circular polarization asymmetry of the gamma-ray flux from dark matter annihilation in the Galactic Center in future gamma-ray polarimetry experiments.
This work proposes a wideband 26-33 GHz multiple-input- multiple-output (MIMO) receiver (RX) array that leverages time-modulation operation to achieve concurrent steerable multibeam MIMOs (MB-MIMOs) ...using only one single array beamformer. Time-modulated arrays (TMAs) introduce time as an additional degree of freedom to concurrently sample and multiplex multiple received signals in various incident angles. In other words, time modulation on the RX array enables spatial-spectral mapping that maps received information in different directions to different frequency components in received spectrum with crossbeam isolation, which can be de-modulated by downstream circuits. Thus, the proposed TM MB-MIMO RX array supports concurrent space division multiple access (SDMA) communication with only one beamformer. Furthermore, with built-in phase shifters, the TM MB-MIMO RX also achieves fast-beam scanning with low hardware complexity. A proof-of-concept 26-33 GHz TM MB-MIMO RX array is implemented in the GlobalFoundries 45 nm CMOS RF silicon on insulator (SOI). The demonstrated RX element shows <inline-formula> <tex-math notation="LaTeX">S_{11} < -10 </tex-math></inline-formula> dB across 24-32 GHz, and its maximum conversion gain (CG) is 28 dB with a 3 dB bandwidth of 26-33 GHz. The measured noise figure (NF) is 5.78 dB at 28 GHz with RX input-referred IP<inline-formula> <tex-math notation="LaTeX">_{\mathrm {1\,dB}} </tex-math></inline-formula> of −38 dBm. The proposed RX supports wideband-16/64 QAM single carrier modulations with maximum modulation speeds of 2.4/4.2 Gb/s, respectively. The demonstrated MB-MIMO RX array achieves five concurrent beams with good crossbeam isolation using only four-element and one analog beamformer and supports wideband-16/64 QAM single carrier modulations on each beam.
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