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Based on the growing range of applications for polycations in research and commercial materials, a continuing need exists to advance the fundamental knowledge and understanding of this class of materials. Spectroscopic and solution properties characterizations of noncovalently labeled, fluorescent Alexa Fluor® dye complexes of two commercial polycations, poly(2-(trimethylamino) ethyl methacrylate) monocation and poly[bis[2-chloroethyl] ether-alt-1,3-bis[3-(dimethylamino) propyl] urea] dication are reported to help address this need. A variety of fluorescence spectroscopic methods are used with a special emphasis on fluorescence correlation spectroscopy (FCS) which is applied to characterize the Stokes radius (RS) and equilibrium dissociation constants (Kd) of dye-polycation complexes at nanomolar dye concentrations. Resulting RS values indicate dye binding to individual polycation chains. Measured Kd values in the sub-micromolar range are consistent with strong dye binding. Increasing solution ionic strength with sodium chloride addition inhibits dye binding and decreases the RS of dye-polycation complexes due to size collapse of polycation chains. The complexes differ in their solution stability to ionic strength changes suggesting that both electrostatic and hydrophobic binding interactions influence dye binding. This study establishes the viability of noncovalent dye-polycation complexation in concert with FCS characterization as a general approach for investigating the properties of quaternary ammonium ion containing polycations in aqueous solution.

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INTRODUCTION: In Malaysia, Hemoglobin Constant Spring (Hb CS) is the most common non-deletional α-thalassemia, caused by a mutation at the termination codon of the α2-globin gene (TAA>CAA). Detection typically involves identifying an abnormal peak at zone 2 on capillary electrophoresis (CE) or a small peak at the C-window on high-performance liquid chromatography (HPLC), indicative of Hb CS. OBJECTIVE: This study aimed to investigate the correlation between HPLC and CE in detecting Hb CS, evaluating their respective diagnostic accuracies and limitations. METHODS: A cross-sectional study was conducted at Hospital Sultanah Nur Zahirah involving secondary school students (Form 4) from Terengganu who participated in a thalassemia screening program conducted by the Ministry of Health (MOH) from January 2019 to December 2022. Blood samples from subjects showing a positive peak in zone 2 of CE and a small peak at the C-window of HPLC were selected. Molecular studies of these samples were performed to confirm the presence of Hb CS. For the statistical analysis, the Pearson correlation coefficient was employed to assess the relationship between CE and HPLC results. RESULTS: Hb CS was confirmed in all samples by molecular studies, revealing 92.3% heterozygous, 7.2% compound heterozygous, and 0.5% homozygous cases. CE detected 92.3% of heterozygous Hb CS cases, while HPLC detected only 48.2%. For compound heterozygous Hb CS, CE detected 100%, whereas HPLC detected 89.3%. Both homozygous cases were detected by CE and HPLC. The Pearson correlation coefficient test showed a significant linear relationship (p<0.001) between CE's zone 2 peak values and HPLC's C-window peaks (n=389).  Conclusion: These findings highlight the efficacy of CE as a reliable method for Hb CS detection, suggesting its potential superiority over traditional HPLC in clinical settings.

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As one of methods for in vitro selection, a flow reactor type washing/selection system seems to be effective, where a ligand library is composed of "genotype-phenotype linking molecules". In this system, high affinity ligands are selected by their respective "residual ratio" given by exp(-koff×t), where koff is the dissociation rate constant and t is the washing time. In this paper, we mathematically considered the following possibility. When the washing/selection dynamics obeys the residual ratio exp(-koff×t) deterministically and mole fraction measurement for sampled sequences by next-generation sequencing (NGS) is performed ideally, the "relative value" of koff for each of high-ranking sequences can be estimated simultaneously. In addition to these, when the residual ratio for the whole ligand population is measured correctly, the "absolute value" for each sequence can be estimated. We deduced formulas to present the relative and absolute estimates, and mathematically analyzed the effect of fluctuations in the number of NGS reads on the estimates in details. These were confirmed by numerical simulations.

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Pain has been defined as an unpleasant sensory and emotional experience associated with or resembling that associated with actual or potential tissue damage. Pets often experience the same pain as people; however, dental pain is often overlooked, discounted, or unseen/hidden in patients, as the inability to communicate does not negate the possibility that a human or a nonhuman animal experiences pain. This article discusses types of pain and the methods and medications available to treat and prevent oral pain.

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Partial accelerated life tests (PALTs) are employed when the results of accelerated life testing cannot be extended to usage circumstances. This work discusses the challenge of different estimating strategies in constant PALT with complete data. The lifetime distribution of the test item is assumed to follow the power half-logistic distribution. Several classical and Bayesian estimation techniques are presented to estimate the distribution parameters and the acceleration factor of the power half-logistic distribution. These techniques include Anderson-Darling, maximum likelihood, Cramér von-Mises, ordinary least squares, weighted least squares, maximum product of spacing and Bayesian. Additionally, the Bayesian credible intervals and approximate confidence intervals are constructed. A simulation study is provided to compare the outcomes of various estimation methods that have been provided based on mean squared error, absolute average bias, length of intervals, and coverage probabilities. This study shows that the maximum product of spacing estimation is the most effective strategy among the options in most circumstances when adopting the minimum values for MSE and average bias. In the majority of situations, Bayesian method outperforms other methods when taking into account both MSE and average bias values. When comparing approximation confidence intervals to Bayesian credible intervals, the latter have a higher coverage probability and smaller average length. Two authentic data sets are examined for illustrative purposes. Examining the two real data sets shows that the value methods are workable and applicable to certain engineering-related problems.

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In the quest for sustainable and renewable energy sources, researchers and engineers have explored innovative technologies to harvest energy from various environmental sources. Dielectric elastomer generators (DEGs) with high energy harvesting performance have been proven to be promising energy collectors, but achieving a high dielectric constant (ε') and low electrical conductivity (EC) under high electric fields of dielectric elastomer (DE) simultaneously is a struggle, which poses significant challenges. In this study, high-content carboxyl group-grafted liquid polybutadiene (HCPB) is synthesized and then adopted as an organic dielectric filler to blend and cocross-link with a butadiene rubber (BR) matrix to prepare DE composites with high energy harvesting performance. The introduction of carboxyl groups enhances polarization while trapping free Al3+ in the matrix, which revolutionarily achieves a significant increase in ε' under extremely low EC. Ultimately, the contradiction between increased ε' and decreased EC under high electric fields is reconciled, resulting in a 30 HCPB/BR composite with high energy density (w = 91.9 mJ/cm3) and fine power conversion efficiency (PCE = 24.1%). This advancement paves the way for the development of HCPB/BR composite-based DEGs with enhanced ε' and energy harvesting performance.

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The determination of the dissociation constant (Kd) is pivotal in biochemistry and pharmacology for understanding binding affinities in chemical reactions, which is crucial for drug development and comprehending biological systems. Here, we introduce single-molecule Fluorescence Resonance Energy Transfer (smFRET)-based method for determining Kd, alongside the conventional electrophoretic mobility shift assay (EMSA) method of Kd, offering insights into thermodynamic interactions between proteins and substrates. The smFRET approach is highlighted for its ability to accurately measure binding and dissociation kinetics through fluorescence labeling and the intrinsic nature of protein-DNA interactions, representing a significant advancement in the fields of molecular biology and pharmacology.

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CONTEXT: The reaction force constant ( κ ), introduced by Professor Alejandro Toro-Labbé, plays a pivotal role in characterizing the reaction pathway by assessing the curvature of the potential energy profile along the intrinsic reaction coordinate. This study establishes a novel link between κ and the reactivity descriptors of conceptual density functional theory (c-DFT). Specifically, we derive expressions that relate the reaction force constant to nuclear softness and variations in chemical potential. Our findings indicate that regions of the reaction pathway where κ is negative match with significant electronic structure rearrangements, while positive κ regions match mostly with geometric rearrangements. This correlation between κ and c-DFT reactivity descriptors enhances our understanding of the underlying forces driving chemical reactions and offers new perspectives for analyzing reaction mechanisms. METHODS: The internal reaction path for the proton transfer in SNOH, chemical potential, and nuclear softness were computed using DFT with B3LYP exchange-correlation functional and 6-311++G(d,2p) basis set.

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Background: Locking plates are one of the most frequently used implants in surgical treatment of displaced proximal humeral fractures. In spite of this established implant and a standardized approach, reduced shoulder function might remain a mid-to long-term issue, furthermore scars may influence patient satisfaction as a cosmetic issue. Indications for a second surgery to remove implant and/or scar revision are common questions in this context.The aim of the present study was to assess the benefit of a second surgery, including implant removal and scar revision surgery, on patients' satisfaction under functional and cosmetic aspects. Methods: Patients following displaced proximal humeral fractures treated by open reduction and internal fixation with a locking plate osteosynthesis via a delto-pectoral approach following implant removal were included retrospectively. A follow-up took place anamnestically before the incident or the primary surgery [A], before second surgery [B], and after second surgery (scar revision/implant removal) [C]. Functional outcome (Constant Score (CS)) of both shoulders was obtained using a patient-reported outcome measure to evaluate the contralateral side as well as percentage CS (%CS). Furthermore, the cosmetic outcome was evaluated for color, contour, and size. Results: The clinical data of n = 81 patients with displaced proximal humeral fractures and the consecutive open reduction and internal fixation with a locking plate (51 women = 63.0% and 30 men = 37.0%; mean age: 53.7 ± 16.6 years) via a standardized deltopectoral approach could be included. The mean CS) before sustaining the humeral fracture or primary surgery [A] was anamnestically 85.8 ± 8.5 points and %CS 99.4 ± 8.4%. After open reduction and internal with a locking plate osteosynthesis [B], the mean CS was 72.2 ± 9.1 points and %CS 84.5 ± 8.7%. Following the scheduled implant removal and scar revision [C], the CS was 80 ± 13.1 points and %CS 92.3 ± 14.1%. After primary surgery, 26 patients (32.1%) complained about the scar because of color, contour, or size before the second surgery, and 23 patients (28.4%) afterwards. Conclusion: Implant removal after locking plate osteosynthesis in proximal humeral fractures via a delto-pectoral approach leads to an improved outcome both functionally and cosmetically. CS as well as scar situation and patients' overall satisfaction could be improved with a second surgery. Nevertheless, the need for a second surgery depends on the patients' functional and cosmetic demands.

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Background: Martinel et al described an intraoperative ultrasound technique to easier identify calcification (CA) under arthroscopy. Our hypothesis was that intraoperative ultrasound monitoring allowed better evacuation of calcific tendinopathy. Our aim was to determine whether ultrasound monitoring improved the short-term clinical and radiological outcomes of calcific tendinopathy. Methods: A prospective, single-center, single-operator, consecutive study conducted between February 2020 and June 2023. The inclusion criterion was surgical treatment for evacuation of symptomatic macro-centimetric CA type A or B. The first 20 patients were operated on using the standard surgical technique and the next 20 under ultrasound control. The mean age at surgery was 49.8 years (minimum: 28 years; maximum: 64 years). Patients were reviewed at 6 weeks and 3 months. The evacuation of the CA was checked at 6 weeks by X-ray. Results: In the standard technique group, the mean preoperative Constant score was 41.4/100 (±15.07). Postoperatively, the Constant score was 58.88/100 (±15.28) at 6 weeks and 69.16/100 (±13.86) at 3 months. The mean preoperative Subjective Shoulder Value (SSV) was 39.0% (±18.61). Postoperatively, the SSV was 64.0% (±17.21) at 6 weeks and 79.47% (±16.06) at 3 months. In the ultrasound control group, the preoperative Constant score was 44.48/100 (±14.28) and 58.18/100 (±15.64) at 6 weeks and 66.87/100 (±18.45) at 3 months postoperatively. The mean preoperative SSV was 40.0% (±16.54) and 61.75% (±18.59) at 6 weeks and 76.05% (±19.62) at 3 months postoperatively. There was no significant postoperative difference in Constant score (P = .732) or SSV (P = .566) between the 2 groups. There was a significant difference (P = .004) between the 2 groups in terms of complete evacuation of the CA with the standard technique in 65% of cases (13 patients out of 20) and with intraoperative ultrasound monitoring in 95% of cases (19 patients out of 20). Conclusion: There was no significant postoperative difference in Constant score and SSV between the 2 groups in the short term. Evacuation of calcification was significantly better with ultrasound monitoring.

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Increased expression and activity of the PD-L1/PD-1 pathway suppresses the activation of cytotoxic T cells, which is vital in anti-tumour defence, allowing tumours to rise, expand and progress. Current strategies using antibodies to target PD-1/PD-L1 have been very effective in cancer therapeutics and companion diagnostics. Aptamers are a new class of molecules that offer an alternative to antibodies. Herein, the systematic evolution of ligands by exponential enrichment (SELEX) using agarose slurry beads was conducted to isolate DNA aptamers specific to recombinant human PD-L1 (rhPD-L1). Isolated aptamers were sequenced and analysed using MEGA X and structural features were examined using mFold. Three aptamer candidates (P33, P32, and P12) were selected for evaluation of binding affinity (dissociation constant, Kd) using ELONA and specificity and competitive inhibition assessment using the potentiostat-electrochemical method. Among those three, P32 displayed the highest specificity (8 nM) against PD-L1. However, P32 competes for the same binding site with the control antibody, 28-8. This study warrants further assessment of P32 aptamer as a potential, cost-effective alternative tool for targeting PD-L1.

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The detection of ethanol-water solution concentration plays an important role in industries, medical care, food and other aspects, which has attracted much attention. In this paper, a 632.8 nm laser combined with the oblique-incidence reflectivity difference (OIRD) method was used to obtain a signal linearly related to the solution concentration and containing the information of the dielectric constant of the solution. Combined with a variety of deep learning algorithms, ethanol-water solutions with a volume concentration of 0-95 % are detected. Among them, the prediction accuracy of the MLP, CNN, LSTM, CNN + BiLSTM + Attention models were 93.65 %, 96.54 %, 97.12 %, 99.23 %, respectively. The experimental results indicate that the OIRD method can achieve rapid, non-destructive, accurate and reliable detection of ethanol-water solutions.

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Lyotropic chiral nematic cellulose nanocrystals (CNCs) have attracted significant attention and great progress has been made. Investigating their physical parameters, especially the twist elastic constant (K22), is pivotal for advancing our comprehension of fundamental viscoelastic property of chiral nematic phase. In this study, we demonstrate a straightforward method to simultaneously estimate K22 and helical twisting power (Kt) of chiral nematic CNCs. This method involves analyzing rheology properties and electro-response of CNCs, focusing on the rotational dynamics and structural reconfiguration of CNC tactoids under an electric field. By examining the rotation dynamics of CNC tactoids under an electric field, together with the viscosity characterization, the anisotropic dielectric susceptibility (∆χ) of chiral nematic CNC along the helix axis was determined. Subsequently, K22/∆χn was extracted by analyzing CNC tactoid pitch evolution under an electric field, employing the de Gennes model. The K22 for different concentrated CNCs is finally estimated by integrating experimental results and theory. It is shown that the chiral nematic CNCs present concentration-dependent K22, ranging from 0.05 to 0.14 pN, while Kt spans from 0.06 to 0.14 pN/µm. This study offers a comprehensive understanding of the CNC fundamental viscoelastic property and opens up new avenues for K22 measurement in other lyotropic liquid crystals.

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This paper describes a 'constant head-transient method' for estimating permeability and specific storage of tight rock samples, such as shale and crystalline rocks. Experimental tests are conducted using a cylindrical rock sample subjected to confining pressure, through which pressure diffusion occurs from a constant upstream pressure (or constant head) to a finite downstream storage. Unlike the pulse-transient method, the upstream fluid flow into the sample can be measured using a syringe pump because of no change in upstream pressure. By minimizing the downstream storage, the test time can be significantly reduced, but only the downstream pressure transient data do not yield accurate results on permeability and specific storage estimations. By combining the flow data with the pressure data, the proposed method aims at saving the test time and improving the accuracy of their estimations in extremely low permeability rock samples.•A constant head-transient method for measuring the hydraulic properties of tight rocks was developed with a boundary condition of constant upstream pressure and finite downstream storage.•The test time can be saved by minimizing the downstream storage, and the upstream flow can be measured to improve the accuracy in measuring the hydraulic properties.•Combining the flow and pressure objective functions yields the best curve fitting for both pressure and flow curves.

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Unlicensed patient care assistants (PCAs) are often tasked with providing constant observation (CO) of patients with complex health behaviors. The unique demands of CO are poorly understood, making it challenging to design effective training. Four-component instructional design theory suggests the tasks associated with CO feature non-recurrent challenges, such that effective, simulation-based deliberate practice must reflect real-life variability. This study aimed to elucidate the variety of challenges PCAs encounter during CO of patients with complex health behaviors. We used a qualitative descriptive design and developed a preliminary framework to code interviews. The data collection framework was designed to support creating numerous realistic scenarios to support generalized and transferable learning. From our interviews with 16 participants, we identified 1,066 statements associated with variations in CO tasks. We grouped our findings by two domains, "patient factors" and "environmental contexts." Our results revealed many recurring and non-recurring challenges inherent in CO, requiring a range of skills to maintain patient and staff safety. Instructional design elements may include scenarios incorporating environment and resource assessment, cognitive feedback for non-recurrent tasks, novel methods of self-harm initiated by the patient, and incorporating interdisciplinary staff in which the learner must navigate a complex conversation. This study clarifies the task demands of CO and is useful as a task analysis to guide scenario development for simulation-based experiences. A less systematic approach would risk underrepresenting the difficulties inherent in the task, reinforcing a limited set of behaviors that may not generalize well to the non-recurrent challenges in CO.

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Background/Objectives: To evaluate the advanced lens measurement approach (ALMA) formula accuracy using different lens constants available on the user group for laser interference biometry (ULIB) and IOL Con platforms. Methods: In this retrospective, comparative, case-series study, 150 eyes of 160 patients with previous myopic Photorefractive Keratectomy (PRK) or laser-assisted in situ keratomileusis (LASIK), who underwent uneventful cataract surgery and IOL implantation, were examined. The ALMA formula was evaluated to calculate the refractive prediction error (PE), analysing four different categories of lens constants: both nominal and optimized A-Constant for SRKT, which are available on the ULIB and IOL Con platforms. An additional analysis was carried out in this study, evaluating if a decreased ULIB optimized constant (DUOC) with different fixed factors (-1.2 -1.3 -1.4 -1.5) could improve refractive outcomes. Median absolute error (MedAE) and percentage of eyes within ±0.50 and ±1.00 diopters (D) of prediction error were measured as the main outcomes. Results: Comparing the lens factors available on ULIB and IOL Con platforms, the ALMA formula reported a lower MedAE and higher percentages of eyes with a refractive PE within 1.0 D using ULIB nominal constants (all p < 0.05). Using DUOC (-1.3), and there was a statistically significant improvement of both MedAE and of the percentages of eyes with PE within ±0.50 D with the ALMA method compared to nominal ULIB constants (all p < 0.05). Conclusions: The impact of different lens factors in the IOL power calculation after myopic LRS should be carefully evaluated. The ALMA formula, in the absence of optimized constants by zeroing the mean error, should be used by subtracting 1.3 from the optimized ULIB constants available on the IOL Con website. This finding suggests further studies to test which of these constants could work better with the other post-refractive surgery formulas.

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BACKGROUND: Heart disease represents the leading cause of death globally. Timely diagnosis and treatment can prevent cardiovascular issues. An Electrocardiograms (ECG) serves as a diagnostic tool for identifying heart difficulties. Cardiovascular Disease (CVD) often gets identified through ECGs. Deep learning (DL) garners attention in healthcare due to its potential in swiftly diagnosing ECG anomalies, crucial for patient monitoring. Conversely, automatic CVD detection from ECGs poses a challenging task, wherein rule-based diagnostic models usually achieve top-notch performance. These models encounter complications in supervision vast volumes of diverse data, demanding widespread analysis and medical capability to ensure precise CVD diagnosis. OBJECTIVE: This study aims to enhance cardiovascular disease diagnosis by combining symptom-based detection and ECG analysis. METHODS: To enhance these experiments, we built a novel automated prediction method based on a Feed Forward Neural Network (FFNN) model. The fundamental objective of our method is to develop the accuracy of ECG diagnosis. Our strategy employs chaos theory and destruction analysis to combine optimum deep learning features with a well-organized set of ECG properties. In addition, we use the constant-Q non-stationary Gabor transform (CQNGT) to convert one-dimensional ECG data into a two-dimensional picture. A pre-trained FFNN processes this image. To identify significant features from the FFNN output that correspond with the ECG data, we employ pairwise feature proximity. RESULTS: According to experimental findings, the suggested system, FFNN-CQNGT, surpasses other state-of-the-art systems in terms of precision of 94.89%, computational efficiency of 2.114 ms, accuracy of 95.55%, specificity of 93.77%, and sensitivity of 93.99% and MSE 40.32%. CONCLUSION: Contributing an automated ECG-based DL system based on FFNN-CQNGT for early-stage cardiovascular disease identification and classification holds great potential for both patient care and public health.

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Axial coordination engineering has emerged as an effective strategy to regulate the catalytic performance of metal‒N‒C materials for oxygen reduction reaction (ORR). However, the ORR mechanism and activity changes of their active centers modified by axial ligands are still unclear. Here, a comprehensive investigation of the ORR on a series of FeN4‒L moieties (L stands for an axial ligand) is performed using advanced density functional theory (DFT) calculations. The axial ligand has a substantial effect on the electronic structure and catalytic activity of the FeN4 center. Specially, FeN4‒C6H5 is screened as a promising active moiety with superior ORR activity, as further revealed by constant-potential calculations and kinetic analysis. The enhanced activity is attributed to the weakened *OH adsorption caused by the altered electronic structure. Moreover, microkinetic modeling shows that at pH = 1, FeN4‒C6H5 possesses an impressive theoretical half-wave potential of ~1.01 V, superior to the pristine Fe‒N‒C catalysts (~0.88 V) calculated at the same level. These findings advance the understanding of the ORR mechanism of FeN4‒L and provide guidance for optimizing the ORR performance of single-metal-atom catalysts.

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BACKGROUND: The artificial anal sphincter is a device used to treat patients with fecal incontinence who are unable to control their bowel movements on their own. Long-term morphological changes in the tissue surrounding the artificial anal sphincter can cause biomechanical compatibility problems, which seriously affect the clinical application of the artificial anal sphincter. METHODS: In this paper, the superelasticity of shape memory alloys was utilized to design and fabricate a biomechanically compatible constant force clamping artificial anal sphincter. An in vitro simulation system was constructed to verify the effectiveness, safety, and constant force characteristics of the artificial anal sphincter. RESULTS: The experimental results demonstrated that the artificial anal sphincter could be effectively closed with no leakage of the liquid-like intestinal contents, which are most likely to leak. The pressure of the artificial anal sphincter on the intestinal tube gradually increased and eventually became constant during closure, and the pressure value was always less than the intestinal blood supply pressure threshold. CONCLUSIONS: In this paper, we designed an artificial anal sphincter based on biomechanical compatibility and the corresponding in vitro simulation experimental program and preliminarily verified the effectiveness, safety, and constant force characteristics of the artificial anal sphincter.

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CRTAM (Class-I MHC restricted T cell-associated molecule) is a member of the Nectin-like family, composed of two extracellular domains, one constant domain (IgC) and another variable domain (IgV), expressed in activated CD8 T cells, epithelial cells, natural killer (NK) cells, and in a subpopulation of CD4 T cells. CRTAM recognizes the ligand Nectin-like 2 (Necl2) through the IgV domain. However, the role of the IgC domain during this ligand recognition has yet to be understood. In this study, we show the purification of soluble-folded Ig domains of CRTAM, and we demonstrate that the IgC domain forms a homodimer in solution via hydrophobic interactions. By surface plasmon resonance (SPR) analysis, we also demonstrate that CRTAM binds to Necl2 with an affinity of 2.16 nM. In conclusion, CRTAM's IgC is essential for a high-affinity interaction with Necl-2.