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This brief describes the design and characteristics of a wideband low-noise transconductance amplifier (LNTA) based on cascode inverter cells for use in surface acoustic wave (SAW) filter-less receivers (RXs). Compared to conventional low-noise amplifiers (LNAs), LNTAs offer superior linearity as they process signals in the current mode. A novel derivative superposition (DS) method is introduced to enhance the third-order input intercept point (IIP3), and the noise canceling (NC) technique is employed to overcome the inherent trade-off between noise figure (NF) and wideband input impedance matching. The circuit design process is accelerated using Bayesian optimization. Furthermore, the NF and IIP3 of the LNTA can be tuned by adjusting the input bias voltage. The chip is fabricated using 40-nm low-power (LP) CMOS technology. Experimental results demonstrate that the S11 is lower than -10 dB in the frequency range of 0.1-1.95 GHz, with a maximum transconductance gain of 126 mS and a minimum NF of 1.5 dB. The average IIP3 and output 1 dB compression point (OP1dB) over the frequency band is 4 dBm and 1.6 dBm, respectively. The blocker NF is 4.25 dB under a -15 dBm blocker and the blocker P1dB is -19.9 dBm. The power dissipation is 22 mW at a 1.25 V supply. Notably, the chip occupies only 0.0032 mm2 without on-chip inductors and capacitors.

In this paper, we propose an analog circuit building block generator, which is composed of a layout-aware analog circuit sizing scheme and an automated analog circuit layout generator. We reformulate the analog circuit sizing problem as a novel constrained multi-objective optimization problem and propose a multi-objective Bayesian optimization scheme that can find multiple different qualified designs. We further leverage a nested multi-fidelity Bayesian optimization method in layout-aware sizing to counterbalance the schematic-level simulation and the expensive post-layout simulation without losing efficiency. The automated layout generator enables the in-loop layout generation, and thus it is possible to find a set of valid post-layout results directly. The experimental results on three real-world analog circuits have demonstrated the efficiency of our proposed approach.

Thermogenic adipocytes, including brown and beige adipocytes, are capable of dissipating energy via heat production in response to external stimuli, such as cold exposure and exercise. This distinct feature makes them promising targets for therapy of obesity and related metabolic disease. In most mammals, the thermogenic function relies on uncoupling protein 1 (UCP1), which creates a proton leak across the inner mitochondrial membrane, diverting protons away from ATP synthesis and resulting in heat dissipation. However, that is not the case in pigs. Accumulating evidence suggested that in pigs neither functional UCP1 nor brown adipocytes were identified, which might be the leading cause for cold stress-caused neonatal mortality and greater adiposity. In our previous study, beige adipocyte formation was found in cold-tolerant pig breeds, together with the finding that UCP1 knock-in improved thermoregulatory ability and decreased fat deposition in pigs, suggesting the potential application of beige induction in pigs for both agricultural purpose and biomedical implication. In this context, we review the anatomical features, developmental origins, plasticity, transcriptional regulation, and the metabolic benefits of thermogenic adipocytes. Particularly, we describe the contribution of beige adipocytes and reconstitution of UCP1 to improve cold sensitivity and decrease fat deposition in pigs. Furthermore, future undertaking regarding beige adipocyte formation in pigs and its potential application is also discussed.

RNF20, an E3 ligase critical for monoubiquitination of histone H2B at lysine 120 (H2Bub), has been implicated in the regulation of various cellar processes; however, its physiological roles in adipocytes remain poorly characterized. Here, we report that the adipocyte-specific knockout of Rnf20(ASKO) in mice led to progressive fat loss, organomegaly and hyperinsulinemia. Despite signs of hyperinsulinemia, normal insulin sensitivity and improved glucose tolerance were observed in the young and aged CD-fed ASKO mice. In addition, high-fat diet-fed ASKO mice developed severe liver steatosis. Moreover, we observed that the ASKO mice were extremely sensitive to a cold environment due to decreased expression levels of brown adipose tissue (BAT) selective genes, including uncoupling protein 1 (Ucp1), and impaired mitochondrial functions. Significantly decreased levels of peroxisome proliferator-activated receptor gamma (Pparγ) were observed in the gonadal white adipose tissues (gWAT) from the ASKO mice, suggesting that Rnf20regulates adipogenesis, at least in part, through Pparγ. Rosiglitazone-treated ASKO mice exhibited increased fat mass compared to that of the non-treated ASKO mice. Collectively, our results illustrate the critical role of RNF20 in control of white and brown adipose tissue development and physiological function.

The origin of the long lifetime of self-trapped exciton emission in low-dimensional copper halides is currently the subject of extensive debate. In this study, we address this issue in a prototypical zero-dimensional copper halide, Cs2(C18)2Cu2I4-DMSO, through magneto-optical studies at low temperatures down to 0.2 K. Our results exclude spin-forbidden dark states and indirect phonon-assisted recombination as the origin of the long photoluminescence lifetime. Instead, we propose that the minimal Franck–Condon factor of the radiative transition from excited states to the ground state is the decisive factor, based on the transition probability analysis. Our findings offer insights into the electronic processes in low-dimensional copper halides and have the potential to advance the application of these distinctive materials in optoelectronics.

Heparan sulfate (HS), which consists of repeating disaccharide units, plays an essential role in inflammation and viral infections. Heparanase (encoded by the HPSEgene) can cleave the HS chains of heparan sulfate proteoglycans (HSPGs), which are known to be important participants in immune responses. HPSE2(heparanase 2) is a homologous gene of HPSE. To investigate the functions of HS, which is the primary receptor of the porcine reproductive and respiratory syndrome virus (PRRSV), the two genes involved in the metabolic process of HS were studied. Here, we present a study of tissue expression profiles, polymorphisms of the HPSEand HPSE2genes, and the changes of their mRNA levels in porcine alveolar macrophages (PAMs) induced by PRRSV. Both genes are preferentially expressed in porcine immune or immune-related organs under normal conditions, e.g., in the lung, spleen, and lymph node. Moreover, a synonymous mutation c.750A>G located in exon5 of the HPSEgene was detected, and was significantly associated with the white blood cell (WBC) count, red blood cell (RBC) count, hemoglobin (HGB), and hematocrit (HCT) in the peripheral blood (p< 0.05). A single nucleotide polymorphism (SNP) c.2073A>G was found in the HPSE2gene and association analysis showed that it was significantly associated with the WBC content in the blood (p< 0.05). Upon stimulation in healthy piglets with PRRSV, the HPSEmRNA was obviously up-regulated, while the HPSE2mRNA did not induce a prominent change in PAMs.Heparan sulfate (HS), which consists of repeating disaccharide units, plays an essential role in inflammation and viral infections. Heparanase (encoded by the HPSEgene) can cleave the HS chains of heparan sulfate proteoglycans (HSPGs), which are known to be important participants in immune responses. HPSE2(heparanase 2) is a homologous gene of HPSE. To investigate the functions of HS, which is the primary receptor of the porcine reproductive and respiratory syndrome virus (PRRSV), the two genes involved in the metabolic process of HS were studied. Here, we present a study of tissue expression profiles, polymorphisms of the HPSEand HPSE2genes, and the changes of their mRNA levels in porcine alveolar macrophages (PAMs) induced by PRRSV. Both genes are preferentially expressed in porcine immune or immune-related organs under normal conditions, e.g., in the lung, spleen, and lymph node. Moreover, a synonymous mutation c.750A>G located in exon5 of the HPSEgene was detected, and was significantly associated with the white blood cell (WBC) count, red blood cell (RBC) count, hemoglobin (HGB), and hematocrit (HCT) in the peripheral blood (p< 0.05). A single nucleotide polymorphism (SNP) c.2073A>G was found in the HPSE2gene and association analysis showed that it was significantly associated with the WBC content in the blood (p< 0.05). Upon stimulation in healthy piglets with PRRSV, the HPSEmRNA was obviously up-regulated, while the HPSE2mRNA did not induce a prominent change in PAMs.

The sulfation behavior of calcined raw meal was investigated in a laboratory fix-bed reactor under conditions typically for SO2 capture in the kiln inlet housing used in cement production. The initial period is characterized with a fast-increasing conversion, while the second period shows a slow-increasing conversion. A desirable temperature exists for sulfation of calcined raw meal. A smaller particle size favors the sulfation reaction. The initial conversion rate is significantly promoted by a higher SO2 concentration. The SEM examinations show that the sulfation process involves nucleation and growth of CaSO4 grains- the sulfation product. Increasing the temperature and extending the time result in fewer but larger CaSO4 grains in the product layer.