Measuring the Adsorption Cross Section of YOYO-1 to Immobilized DNA Molecules.

Many interactions between small molecules and particles occur in solutions. They are surrounded by other molecules that do not react, for example, biological processes in water, chemical reactions in gas or liquid solutions, and environmental reactions in air and water. However, predicting the rate of such diffusive interactions remains challenging, due to the random motion of molecules in solutions, as exampled by the famous Brownian motion of pollen particles. In this report, we experimentally confirmed that a disruptive rate equation we have published before can predict the association rate of typical adsorption at interfaces, which has a surprising fraction order of 4/3 that has not been considered before. This could be an important step toward a generalized method to predict the adsorption rate of many reactions.

Physical Chemistry Lab for Data Analysis of COVID-19 Spreading Kinetics in Different Countries.

The COVID-19 pandemic has passed. It gives us a real-world example of kinetic data analysis practice for our undergraduate physical chemistry laboratory class. It is a great example to connect this seemingly very different problem to the kinetic theories for chemical reactions that the students have learned in the lecture class. At the beginning of the spring 2023 semester, we obtained COVID-19 kinetic data from the "Our World in Data" database, which summarizes the World Health Organization (WHO) data reported from different countries. We analyzed the effective spreading kinetics based on the susceptible-infectious-recovered-vaccinated (SIR-V) model. We then compared the effective rate constants represented by the real-time reproduction numbers ( R t ) underlining the reported data for these countries and discussed the results and the limitations of the model with the students.

[Status of outcome measures in randomized controlled trials of kidney-tonifying and blood-activating method in treatment of knee osteoarthritis].

This study assesses the status of outcome measures in the randomized controlled trial(RCT) involving the kidney-tonif-ying and blood-activating method for treating knee osteoarthritis(KOA), aiming to establish a theoretical foundation for the development of a core set of outcome measures in traditional Chinese medicine(TCM) treatment of KOA. The relevant articles were retrieved from CNKI, Wanfang, VIP, SinoMed, PubMed, EMbase, Cochrane Library, and Web of Science, in addition to ClinicalTrials.gov and the China Clinical Trial Registration Center, with the time interval from inception to August 2023. The RCT of treating KOA with the kidney-tonifying and blood-activating method was included. Two assessors independently conducted literature screening, data collection, and qualitative analysis to compile the outcome measure results. A total of 350 RCTs were included, involving 165 outcome measures with the total frequency of 1 462. These outcome measures were categorized into six domains: symptom and sign measures(23) with the frequency of 718(49.1%), TCM symptom and syndrome measures(3) with the frequency of 53(3.6%), physical examination measures(130) with the frequency of 506(34.6%), quality of life measures(4) with the frequency of 20(1.3%), long-term efficacy measures(2) with the frequency of 6(0.4%), and safety measures(3) with the frequency of 159(10.9%). Additionally, 53 studies used TCM syndrome and symptom scores as indicators of efficacy, employing eight distinct measurement tools. The RCTs involving the kidney-tonifying and blood-activating method for treating KOA had a variety of problems, such as unclear prio-ritization of outcome measures, diversity in measurement tools, absence of standardized assessment criteria for specific measures, and non-standardized usage. These problems affected the research quality and reliability. Hence, it is advisable to draw upon international expertise, improve research design, and merge TCM efficacy characteristics with clinical research to establish a core set of KOA outcome measures aligned with TCM principles.

Monitoring Phase Separation and Dark Recovery in Mixed Halide Perovskite Clusters and Single Crystals Using In Situ Spectromicroscopy.

Mixed halide perovskites (MHPs) are a group of semiconducting materials with promising applications in optoelectronics and photovoltaics, whose bandgap can be altered by adjusting the halide composition. However, the current challenge is to stabilize the light-induced halide separation, which undermines the device's performance. Herein we track down the phase separation dynamics of CsPbBr1.2I1.8 MHP single cubic nanocrystals (NCs) and clusters as a function of time by in situ fluorescence spectromicroscopy. The particles were sorted into groups 1 and 2 using initial photoluminescence intensities. The phase separation followed by recovery kinetics under dark and photo blinking analysis suggests that group 1 behaved more like single NCs and group 2 behaved like clusters. Under the 0.64 W/cm2 laser illumination, the phase shifts for single NCs are 3.4 ± 1.9 nm. The phase shifts are linearly correlated with the initial photoluminescence intensities of clusters, suggesting possible interparticle halide transportation.

A critical overview of systematic reviews and meta-analyses of extracorporeal shockwave therapy for knee osteoarthritis.

Knee Osteoarthritis (KOA) has become a serious health issue for elderly patients. Several systematic reviews (SRs) and Meta-Analyses (MAs) have reported extracorporeal shockwave therapy (ESWT) has widely been used in the treatment of KOA. This overview aims to summarize and evaluate the available evidence for the efficacy of ESWT for KOA. Eight databases were searched from inception to December 4, 2022. The methodological quality of the included SRs/MAs was assessed by Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR 2) and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool was used to assess the quality of the included studies in terms of outcome indicators. Eight SRs/MAs were finally included in this study. The results of the methodological quality of the included SRs/MAs were generally unsatisfactory. The limitations were a lack of explaining the reasons for selection, a list of excluded literature, reporting bias assessment, and reporting the potential sources of conflict of interest. A total of 49 outcome indicators were assessed by using the GRADE tool. Only 3 items were assessed as moderate quality and the remaining indicators were rated as low and very low. Limitations were the most common downgraded factors. ESWT is regarded as a safe and therapeutically effective non-pharmacological method for the treatment of KOA. However, the reliability of the results is affected by the generally low methodological and evidential quality of the included SRs/MAs. Future researchers should improve the quality of original studies and SRs/MAs to provide a higher level of evidence-based medical evidence.

Insect multimeric G-quadruplexes fold into antiparallel structures of different compactness and stability in K+ and Na+ solutions.

Human telomere sequences (TTAGGG)n fold into G-quadruplexes with different conformations in K+ and Na+ solutions, which are highlighted for their potential as antitumor drug targets. Moreover, human multimeric G-quadruplexes have been broadly studied potentially for screening ligands with higher selectivity than monomeric G-quadruplexes. Most insects have telomeres consisting of pentanucleotide (TTAGG) repeats, which fold into an antiparallel structured G-quadruplex with a two-layer G-planar in a K+ solution. However, the structure of insect telomeric G-quadruplexes in Na+ solutions and their higher-order structures have not been explored. The quinoline derivative BMPQ-1 has been reported to bind human multimeric G-quadruplex. This study compared the stability and compactness of insect monomeric and multimeric G-quadruplex structures in K+ and Na+ solutions and further validated the interaction between BMPQ-1 and insect multimeric G-quadruplexes. Circular dichroism (CD) spectral scanning analysis revealed that although the insect telomeric G-quadruplex folds into an antiparallel structure in both K+ and Na+ solutions, all the insect telomeric G-quadruplexes are more stable in Na+ solutions. Fluorescence resonance energy transfer (FRET) analysis indicated insect telomeric G-quadruplexes have a more compact structure in Na+ solutions. BMPQ-1 exhibited higher selectivity for insect multimeric G-quadruplex Bom37 than monomeric G-quadruplex Bom17, and had a different binding pattern to Bom37 G-quadruplex in K+ and Na+ solutions. Finally, BMPQ-1 was found to have a significant inhibitory effect on the proliferation of pest cells. This study contributes to our comprehensive understanding of insect telomeric G-quadruplexes.

A 77 GHz Power Amplifier with 19.1 dBm Peak Output Power in 130 nm SiGe Process.

This article reports a two-stage differential structure power amplifier based on a 130 nm SiGe process operating at 77 GHz. By introducing a tunable capacitor for amplitude and phase balance at the center tap of the secondary coil of the traditional Marchand balun, the balun achieves amplitude imbalance less than 0.5 dB and phase imbalance less than 1 degree within the operating frequency range of 70-85 GHz, which enables the power amplifier to exhibit comparable output power over a wide operating frequency band. The power amplifier, based on a designed 3-bit digital analog convertor (DAC)-controlled base bias current source, exhibits small signal gain fluctuation of less than 5 dB and saturation output power fluctuation of less than 2 dB near the 80 GHz frequency point when the ambient temperature varies in the range of -40 °C to 125 °C. Benefiting from the aforementioned design, the tested single-path differential power amplifier exhibits a small signal gain exceeding 16 dB, a saturation output power exceeding 18 dBm, and a peak saturation output power of 19.1 dBm in the frequency band of 70-85 GHz.

A 40-50 GHz RF Front-End with Integrated Local Oscillator Leakage Calibration.

This article presents a transmitter (TX) front-end operating at frequencies covering 40-50 GHz, including a differential quadrature mixer with integrated amplitude and phase imbalance tuning, a power amplifier, and a detection mixer (DM) that supports local oscillator (LO) leakage signal or image signal calibration. Benefiting from the amplitude and phase imbalance tuning network of the in-phase quadrature (IQ) signal generator at the LO input, the TX exhibits more than 30 dBc image signal rejection over the full frequency band without any post-calibration. Based on the LO leakage signal fed back by the DM integrated at the RF output, the LO leakage of the TX has been improved by more than 10 dB through the LO leakage calibration module integrated in the quadrature mixer. When the intermediate frequency (IF) signal is fixed at 1 GHz, the TX's 1 dB compressed output power (OP1 dB) is higher than 13.5 dBm over the operating band. Thanks to the LO leakage signal calibration unit and the IQ signal generator, the TX is compliant with the error vector magnitude (EVM) requirement of the IEEE 802.11aj standard up to the 64-quadrature amplitude modulation (QAM) operating mode.