This paper proposes a transformer-based broadband low-noise amplifier (LNA) for millimeter-wave application. The proposed LNA has four common-source stages. Three transformers are used to connect the ...drains of the former transistors and the sources of the following transistors to boost the transconductances of the following transistors. Thus, the gain of the circuit is effectively increased. In addition, the noise figure (NF) is decreased because the noise contributions of the following stages are further suppressed by the application of the transformers. To enhance the gain bandwidth, the gate inductor in each inter-stage matching network is independently adjusted to separate the main poles of the four stages. The LNA is demonstrated using a commercial 65-nm CMOS process. According to the measurement results, a maximum gain of 17.7 GHz at 67 GHz and a 3-dB gain bandwidth of 35.6 GHz are achieved. The measured NF is 5.4-7.4 dB at 54-67 GHz. The tested input 1-dB gain compression point (IP1dB) ranges from -15.4 to -11.7 dBm in the entire 3-dB gain bandwidth. With 1-V power supply, the LNA consumes 19-mA dc current. The chip size is only 0.37 mm 2 with all pads.
An injection-current-boosting (ICB) locking-range enhancement technique is presented to increase the locking range (LR) of the millimeter-wave (mm-wave) injection-locked frequency triplers (ILFTs). ...With a transformer-based fourth-order injection-coupling network, the parallel capacitance from the injection devices is resonated out over a wide frequency range and the injection current is boosted greatly. Analytical models of the ICB-ILFT are introduced, based on which the current-boosting phenomenon is analyzed. Meanwhile, the design concepts of the ultra-wideband mm-wave ILFT are presented. With the proposed ICB technique, an ICB-ILFT is designed and fabricated in 65-nm CMOS process. With a 0-dBm RF injection source, the ICB-ILFT can be locked from 22.8 to 43.2 GHz without calibration, achieving a 61.8% LR. The power consumption is only 5.0 mW and a 9.5-dB phase noise difference is observed, which is close to the theoretical value.
The effects of three freezing methods, air blast freezing (ABF), immersion freezing (IF) and ultrasound-assisted immersion freezing (UIF), on quality and microstructure of lotus roots were ...investigated. The parameters used to evaluate the freezing methods effect were the freezing time, color, firmness, drip loss, vitamin C and microstructure of the final frozen products. The results showed that the UIF products had several advantages in terms of the freezing time, color, firmness and drip loss over ABF and IF. No significant difference (p > 0.05) of vitamin C content was observed between the ABF and IF products, while significant difference (p < 0.05) of vitamin C was observed between UIF and ABF/IF products. ABF caused the largest destruction to the tissue, while the microstructure of the UIF products was the best preserved. It is concluded that UIF processing was a better freezing method for lotus root with improved quality and less damaged microstructure than the two other methods.
•Lotus root was frozen by three different methods.•Ultrasound-assisted immersion freezing (UIF) was quickest and gave best quality.•Air blast freezing and immersion freezing gave slightly higher vitamin C retention.•Microstructure was best preserved with UIF.•Overall UIF was the best of the three freezing method considered.
•pH dependency of dynamic interfacial tension at fish oil/gelatin interface was studied.•Adsorption kinetics of gelatin at fish oil–water interface was modelled at various pH values.•Variation of ...secondary structure of gelatin was studied at pH range of 4.0–6.0.•Surface charge of gelatin and the dynamic interfacial tension were found to be closely related.•Adsorption kinetics of gelatin at oil–water interface was found to depend on its secondary structure.
The objectives of this study were to quantify the relationship between secondary structure of gelatin and its adsorption at the fish-oil/water interface and to quantify the implication of the adsorption on the dynamic interfacial tension (DST) and emulsion stability. The surface hydrophobicity of the gelatin solutions decreased when the pH increased from 4.0 to 6.0, while opposite tend was observed in the viscosity of the solution. The DST values decreased as the pH increased from 4.0 to 6.0, indicating that higher positive charges (measured trough zeta potential) in the gelatin solution tended to result in higher DST values. The adsorption kinetics of the gelatin solution was examined through the calculated diffusion coefficients (Deff). The addition of acid promoted the random coil and β-turn structures at the expense of α-helical structure. The addition of NaOH decreased the β-turn and increased the α-helix and random coil. The decrease in the random coil and triple helix structures in the gelatin solution resulted into increased Deff values. The highest diffusion coefficients, the highest emulsion stability and the lowest amount of random coil and triple helix structures were observed at pH=4.8. The lowest amount of random coil and triple helix structures in the interfacial protein layer correlated with the highest stability of the emulsion (highest ESI value). The lower amount of random coil and triple helix structures allowed higher coverage of the oil–water interface by relatively highly ordered secondary structure of gelatin.
► First report on using various polyols to modify nanoclay galleries by varying sonication power. ► Polyol concentration has little impact on increasing spacing within the nanoclay galleries. ► ...Orientation and folding of polyols greatly impact on altering the nanoclay gallery spacing. ► Larger molecule, viz. maltodextrin showed gallery spacing increased with higher concentration.
Na+-montmorillonite clay (generally referred to as MMT) is very useful for reinforcing polymeric matrix at very low concentrations (typically, 2–5% wt). These clay particles are typically exfoliated before they can demonstrate the significant gains in heat deflection temperature, modulus, and elongation properties. In the case of hydrophilic biopolymer based matrices, such as carbohydrates and chitosan, exfoliating these nanoclay particles needs greater attention because the exfoliation is typically carried out using hydrophobic oligomers through ion-exchange. This study reports a new method of synthesizing completely hydrophilic MMT-assemblages using hydrophilic plasticizers for biopolymers. We used sugar alcohols (glycerol, xylitol with 3 and 5 hydroxyl groups) and polysaccharide maltodextrin to exfoliate the MMT. Sonication was conducted for MMT nanoclay and plasticizers at different weight ratios. It was confirmed that all plasticizer/modifier led to expansion of MMT gallery spacing (d-spacing) and the change in d-spacing could be related to the molecular structure of the plasticizer. Meanwhile, the extent of exfoliation was maximum with maltodextrin (fully exfoliation with 1:10 and 1:20 ratio of MMT:plasticizer) across all test samples and interestingly, glycerol and xylitol samples quickly established within the MMT galleries and exhibited minimal influence with further increase in relative concentrations.
Our study investigated the causal relationship between immune cells, metabolites, and epilepsy using two-sample Mendelian Randomization (MR) and mediation MR analysis of 731 immune cell traits and ...1400 metabolites. Our core methodology centered on inverse-variance weighted MR, supplemented by other methods. This approach was crucial in clarifying the potential intermediary functions of metabolites in the genetic links between traits of immune cells and epilepsy. We found a causal relationship between immune cells and epilepsy. Specifically, the genetically predicted levels of CD64 on CD14-CD16- are positively correlated with the risk of epilepsy (p < 0.001, OR = 1.0826, 95% CI 1.0361–1.1312). Similarly, metabolites also exhibit a causal relationship with both immune cells (OR = 1.0438, 95% CI 1.0087–1.0801, p = 0.0140) and epilepsy (p = 0.0334, OR = 1.0897, 95% CI 1.0068–1.1795), and sensitivity analysis was conducted to further validate these relationships. Importantly, our intermediate MR results suggest that the metabolite Paraxanthine to linoleate (18:2n6) ratio may mediate the causal relationship between immune cell CD64 on CD14-CD16- and epilepsy, with a mediation effect of 5.05%. The results suggest the importance of specific immune cell levels and metabolites in understanding epilepsy’s pathogenesis, which is significant for its prevention and treatment.
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•A novel bulk material was prepared through combining PDMS with either hydrophobic or hydrophilic antibiotics.•For both kinds of antibiotics, the optical transmission of the blend ...films was higher than 90%.•The blend films demonstrated excellent bactericidal and sufficient biofilm inhibition functions.•The blend films yielded a significantly low degree of infection in the rabbit subcutaneous S. aureus infection model.
Infection associated with medical devices is one of the most frequent complications of modern medical biomaterials. Bacteria have a strong ability to attach on solid surfaces, forming colonies and subsequently biofilms. In this work, a novel antibacterial bulk material was prepared through combining poly(dimethyl siloxane) (PDMS) with either hydrophobic or hydrophilic antibiotics (0.1–0.2wt%). Scanning electron microscopy, water contact angle and UV–vis spectrophotometer were used to measure the changes of surface topography, wettability and optical transmission. For both gentamicin sulfate (GS) and triclosan (TCA), the optical transmission of the PDMS-GS and PDMS-TCA blend films was higher than 90%. Drug release studies showed initial rapid release and later sustained release of GS or TCA under aqueous physiological conditions. The blend films demonstrated excellent bactericidal and sufficient biofilm inhibition functions against Gram-positive bacteria (Staphylococcus aureus, S. aureus) measured by LIVE/DEAD bacterial viability kit staining method. Kirby-Bauer method showed that there was obvious zone of inhibition (7.5–12.5mm). Cytocompatibility assessment against human lens epithelial cells (HLECs) revealed that the PDMS-GS blend films had good cytocompatibility. However, the PDMS-TCA blend films showed certain cytotoxicity against HLECs. The PDMS-0.2wt% GS blend films were compared to native PDMS in the rabbit subcutaneous S. aureus infection model. The blend films yielded a significantly lower degree of infection than native PDMS at day 7. The achievement of the PDMS-drug bulk materials with high light transmittance, excellent bactericidal function and good cytocompatibility can potentially be widely used as bio-optical materials.
The crystalline domain changes and lamellar structure observations of sorbitol-plasticized starch nanocomposite had been investigated via synchrotron. Strong interactions were found between ...amylose–sorbitol, resulting in reduced inter-helix spacing of the starch polymer. Achievable dspacing of nanoclay was confirmed to be correlated to the moisture content (mc) within the nanocomposites. SAXS diffraction patterns changed from circular (high mc samples) to elliptical (low mc samples), indicating the formation of long periodic structure and increased heterogeneities of the electron density within the samples. Two different domains sized at around 90Å and 350Å were found for the low mc samples. However, only the ~90Å domain was observed in high mc samples. Formation of the 380Å domain is attributed to the retrogradation behaviour in the absence of water molecules. Meanwhile, the nucleation effect of nanoclay is another factor leading to the emergence of the larger crystalline domain.
•Microstructure of starch nanocomposite was studied by Synchrotron measurements.•Heterogeneity increased for the low moisture content samples.•Two crystalline domains were found in low moisture and nanoclay presence samples.•Retrogradation related to the formation of new emergence of the larger domain.
Migraine is a common neurological disorder that affects more than one billion people worldwide. Recent genome-wide association studies have identified 123 genetic loci associated with migraine risk. ...However, the biological mechanisms underlying migraine and its relationships with other complex diseases remain unclear. We performed a phenome-wide association study (PheWAS) using UK Biobank data to investigate associations between migraine and 416 phenotypes. Mendelian randomization was employed using the IVW method. For loci associated with multiple diseases, pleiotropy was tested using MR-Egger. Single-cell RNA sequencing data was analyzed to profile the expression of 73 migraine susceptibility genes across brain cell types. qPCR was used to validate the expression of selected genes in microglia. PheWAS identified 15 disorders significantly associated with migraine, with one association detecting potential pleiotropy. Single-cell analysis revealed elevated expression of seven susceptibility genes (including ZEB2, RUNX1, SLC24A3, ANKDD1B, etc.) in brain glial cells. And qPCR confirmed the upregulation of these genes in LPS-treated microglia. This multimodal analysis provides novel insights into the link between migraine and other diseases. The single-cell profiling suggests the involvement of specific brain cells and molecular pathways. Validation of gene expression in microglia supports their potential role in migraine pathology. Overall, this study uncovers pleiotropic relationships and the biological underpinnings of migraine susceptibility.
A 60-GHz 4-bit vector-summing phase shifter has been implemented in a 90-nm CMOS process. Based on a tunable current-splitting technique with π-type low-pass filter (LPF) and T-type high-pass filter ...(HPF), a quadrature adjustable amplitude generator is developed to improve the insertion loss and adjust quadrature signals' amplitudes. Variable gain amplifiers (VGAs) that are widely used in traditional phase shifters are replaced by the generator to reduce power consumption. In addition, a balun-based current-reuse technique is applied to further save dc power. The overall consumed direct current is 11 mA under 1.8-V voltage supply. The measured results show that the phase shifter with an output balun (with loss of 1.6 dB) achieves gain of -0.4~2.5 dB at 60 GHz and root mean square (rms) gain error is 0.75~1.6 dB in the frequency regime from 57 to 64 GHz. The peak average gain is 1.1 dB at 59.7 GHz. By employing a calibration method, the measured rms phase error ranges from 2.3° to 7.6° from 57 to 64 GHz. The tested 60-GHz input 1-dB compression point (P 1dB ) and noise figure (NF) for 16 phase states are -9.8 ± 0.8 dBm and 11 ± 1.3 dB, respectively.
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