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Fuzzy C-means (FCM) algorithm is sensitive to image noise and only considers the image numeric feature information, ignoring the spatial constraint relationship between neighbor pixels. In addition, the membership degrees can't describe the image uncertainties effectively, which makes the FCM-based segmentation results inaccurate. Even though the advanced FCM algorithms incorporating local information are robust to image noise to some extent, the image details are not preserved well and the tiny regions are hardly segmented. To resolve this issue, this paper proposed an improved FCM segmentation method based on intuitionistic fuzzy set (IFS), namely IFS_FCM. The proposed method integrated IFS into FCM, which well considered the image uncertainty. Furthermore, it added the spatial neighbor information into the objective function, which improved the robustness to image noise and preserved the image details. The experimental results demonstrate that the image segmentation results of this method are satisfactory. [ABSTRACT FROM AUTHOR]

To solve the problem of signal separation in the system of integration of radar and communication, a signal model based on random stepped-frequency Orthogonal Frequency Division Multiplexing ( OFDM) radar pulses is proposed. By the frequency agility, the communication data is modulated on the radar pulses and then transmitted through random stepped- frequency pulses. Thus, the target range image can be acquired from the correlation of the echo signal and the reference signal, while the communication data is demodulated by means of frequency detection through bandpass filter group without signal separation. Finally, simulation results show that the designed signal realizes decimeter range resolution imaging and high-rate data transmitting in Mbit per second, which can satisfy the requirements of transmitting the mass data. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study is to evaluate the influence of sodium iodide, sodium chloride and sodium sulfate on the formation efficiency of sulfamerazine nanocrystals by wet ball milling. Methods: Sulfamerazine was milled using zirconium oxide beads in a solution containing polyvinylpyrrolidone (PVP) and a sodium salt (iodide, chloride or sulfate). Particle size distributions were evaluated by light diffraction before and after milling. High-performance liquid chromatography was utilized to determine the amount of PVP adsorbed onto sulfamerazine surface. Lyophilized nanocrystals were further characterized by differential scanning calorimetry and dissolution testing. Results: Sulfate ion had more profound effect on reducing particle size via milling than iodide or chloride. We linked our findings to Hofmeister ion series, which indicates that sulfate ions tends to break the water structure, increases the surface tension and lowers the solubility of hydrocarbons in water. We hypothesized that the addition of sulfate ions dehydrated the PVP molecules and enhanced its adsorption onto the sulfamerazine particle surfaces. Consequently, the adsorbed PVP helped to stabilize of the nanosuspension. The nanocrystals that were obtained from the lyophilized milled suspensions exhibited a notable increase in dissolution rate. Conclusion: The addition of sodium sulfate enhanced the formation efficiency of sulfamerazine nanocrystals. [ABSTRACT FROM AUTHOR]

Objective: To mask the bitterness of Chlorpheniramine Maleate via encapsulating drug into Eudragit EPO microparticles, and then incorporate these microparticles into orally disintegrating films (ODF) and orally disintegrating tablets (ODT) for pediatric uses. Methods: Spray drying of water-in-oil emulsion was utilized to encapsulate Chlorpheniramine Maleate into Eudragit EPO microparticles. Based on an orthogonal experimental design L9 (33), polynomial regression models were developed to evaluate correlation between microparticle properties (encapsulation efficiency and drug release) and variables ( X1: weight ratio of polymer to drug, X2: volume ratio of oil to water and X3: Q-flow of spray dryer). ODF and ODT formulations were evaluated including weight variation, content uniformity, tensile strength, disintegration time, friability and dissolution profiles. The bitterness taste test was evaluated in 10 adult volunteers. Results and discussion: From polynomial regression analysis, the best values of variables leading to the optimized microparticles were X1 = 10, X2 = 3 and X3 = 45. The optimized microparticles were incorporated into ODF and ODT with satisfactory weight and drug content uniformity, and acceptable physical strength. Both dosage forms disintegrated immediately (less than 40 s) in simulated saliva solutions. The outcome of taste-masking test indicated that microparticles alleviated drug bitterness significantly; bitterness was not discernible with microparticles incorporated in ODT, whereas only slight bitterness was detected from microparticles incorporated into ODF. Conclusion: Both ODF and ODT are shown to be suitable vehicles for taste masked Chlorpheniramine Maleate microparticles with potential for pediatric uses. [ABSTRACT FROM AUTHOR]

This study aimed to examine the locus of age of acquisition (AoA) and word frequency (WF) effects in Chinese spoken picture naming, using a picture–word interference task. We conducted four experiments manipulating the properties of picture names (AoA in Experiments 1 and 2, while controlling WF; and WF in Experiments 3 and 4, while controlling AoA), and the relations between distractors and targets (semantic or phonological relatedness). Both Experiments 1 and 2 demonstrated AoA effects in picture naming; pictures of early acquired concepts were named faster than those acquired later. There was an interaction between AoA and semantic relatedness, but not between AoA and phonological relatedness, suggesting localisation of AoA effects at the stage of lexical access in picture naming. Experiments 3 and 4 demonstrated WF effects: pictures of high-frequency concepts were named faster than those of low-frequency concepts. WF interacted with both phonological and semantic relatedness, suggesting localisation of WF effects at multiple levels of picture naming, including lexical access and phonological encoding. Our findings show that AoA and WF effects exist in Chinese spoken word production and may arise at related processes of lexical selection. [ABSTRACT FROM AUTHOR]

It has been recognized that a connection may exist between defects of oxide coating and its corrosion protection. Such a link has not been substantiated. We prepare two coatings of anodized aluminum oxide (AAO) and plasma electrolytic oxidation (PEO), and analyze them with Mott-Schottky plots and potentiodynamic polarization scans. The as-grown and annealed AAO coatings exhibit both p-type and n-type semiconductor behaviors. Polarization resistance of the AAO coating increases from (1.8 ± 1.7) × 108 to (4.3 ± 0.5) × 108 Ω·cm2, while corrosion current decreases from (6.1 ± 3.6) × 10−7 to (2.3 ± 0.9) × 10−7 A·cm−2, as annealing temperature increases from room temperature to 400 °C. The parameter analysis on AAO indicates a positive correlation between corrosion current and donor density, a negative correlation between polarization resistance and donor density. The attempt on correlating corrosion potential gives rise to considerable deviation from a linear fit. The results suggest protection of AAO hinges on its donor density, not acceptor. On the PEO coatings, only the n-type behavior is observed. Intriguingly, the donor density of PEO coating is influenced by the annealing temperature of its pre-anodized layer. The most resistant PEO coating, with pre-anodized and 400 °C annealed AAO, exhibits polarization resistance (2.1 ± 0.4) × 109 Ω·cm2 and corrosion current (1.7 ± 0.4) × 10−8 A·cm−2. [ABSTRACT FROM AUTHOR]

Transconductance (gm) is one important figure of merit for benchmarking organic electrochemical transistor (OECT) biosensors, which nevertheless experiences undesired fluctuation instead of keep constant during the target detection of varied concentrations. Light‐matter interplay is recently shown as a potential way to regulate the OECT characteristics, e.g. maximum gm at zero gate bias is achieved. In this work, the challenge of unstable gm is addressed by using a unique metal‐organic framework (MOF)‐derived hollow tube indium sulfide (m‐In2S3) as the photogate. Interestingly, the light irradiation on m‐In2S3 generate a straight transfer curve, leading to a stable gm that is desirable for biological application. Exemplifying by an aptasening, such a device is then tested for protein quantification with a stable sensitivity during the detection. This work features the feasibility of light‐matter interplay to achieve a stable gm in organic electronics. [ABSTRACT FROM AUTHOR]

Addressing challenges in oxygen reduction efficiency and CO 2 endurance is essential for advancing the electrochemical energy conversion performance of solid oxide fuel cells (SOFCs). This investigation introduces an innovative strategy by employing Ce doping to enhance the oxygen reduction kinetics and CO 2 resistance of NdBaCoFeO 5+ δ (NBCF) cathodes. Ce doping effectively regulates the oxygen vacancy content, the ratio of Co3+/Co4+ and Fe3+/Fe4+ in NBCF, leading to substantial improvements in oxygen exchange, lattice diffusion, and charge transfer processes. Consequently, a significant enhancement in the oxygen reduction reaction catalytic activity and CO 2 endurance is achieved. At 800 °C, the introduction of 10 mol% Ce doping results in a 65.3% reduction in Rp, reaching 0.024 Ω cm2. Simultaneously, the power density experiences a 50.8% enhancement, reaching 1.0 W cm−2. The current investigation presents a novel avenue towards the advancement of next-generation high-efficiency and stable cathode materials for SOFCs. [ABSTRACT FROM AUTHOR]

The sluggish kinetics of the oxygen reduction reaction (ORR) and susceptibility to CO 2 poisoning present significant challenges in the application of intermediate temperature solid oxide fuel cells (IT-SOFCs). In this study, bismuth (Bi) was introduced as a dopant for the first time to enhance both the ORR activity and CO 2 tolerance of PrBaCoCuO 5+ δ (PBCCO) cathode. Bi doping serves to concurrently modulate the oxygen vacancy content and carrier concentration. This dual regulation enhances the processes of oxygen adsorption, dissociation, and charge transfer, as evidenced by the distribution of relaxation time (DRT) technique. Furthermore, PBBCCO demonstrates exceptional CO 2 tolerance and remarkable performance recovery following exposure to CO 2 -induced degradation. At 800 °C, the polarization resistance (R p) and maximum power density (MPD) of PBBCCO were 0.026 Ω cm2 and 631 mW cm−2, respectively. Notably, R p was reduced by 52.45%, and MPD exhibited an improvement of 45.11% at 800 °C. These findings highlight the significant impact of Bi doping on the performance of the PBCCO double perovskite cathode, underscoring its crucial importance for future developments of novel cathode materials. [ABSTRACT FROM AUTHOR]

Up to now, most of stimulated-emission-depletion (STED) systems were lens-based bulky systems. Exchanging some spatial light paths with optical fiber components will make the systems more flexible and will benefit various fields. A big problem to achieve this goal is that the STED beam generated by the traditional method of bulky systems cannot be maintained in an optical fiber due to its birefringence. In this article, we will introduce a type of special optical fiber. With the special fiber, a dark hollow beam with doughnut-shaped focal spot and a concentric beam with Gaussian-shaped focal spot can be generated at the same time. Parameters of a sample and a compact STED system based on it are demonstrated. [ABSTRACT FROM AUTHOR]

Cathodes demonstrating elevated electrochemical catalysis and CO 2 endurance are fundamental for solid oxide fuel cells (SOFCs). Herein, Ta/Cu co-doped SrCo 0.8 Ta 0.1 Cu 0.1 O 3- δ (SCTC) and Nb/Cu co-doped SrCo 0.8 Nb 0.1 Cu 0.1 O 3- δ (SCNC) perovskite oxides were prepared and comparative studied as high-performance SOFC cathodes. Due to the synergistic effects of Ta/Cu and Nb/Cu, the oxygen vacancy content, the ratio of Co3+/Co4+, the average bonding energy and the critical radius in the material are well regulated, resulting in the reduction of TEC and enhanced electrochemical catalytic activity in SCTC and SCNC. At 800 °C, SCTC exhibits an ASR of 0.033 Ω cm2, while it is 0.038 Ω cm2 for SCNC. Additionally, SCTC demonstrates a considerable output performance of 0.89 W cm-2, representing a 15.65% improvement over SCNC. This work offers a highly effective approach to developing materials for next-generation energy transformation devices. [ABSTRACT FROM AUTHOR]

Background: Depression and anxiety are topical concerns worldwide, especially among adolescents. Besides, biological rhythm disorder as a candidate mechanism for mood disorders is highly prevalent, but relevant research among adolescents in China is presently limited. We conducted the present study to investigate the distribution of multi-dimensional self-rating biological rhythm disorder and the association of self-rating biological rhythm disorders with depression and anxiety symptoms among Chinese adolescents in different academic stages. Methods: In the cross-sectional study, 3693 students aged 11–23 from Zhengzhou City, Henan Province, China were included. The Patient Health Questionnaire (PHQ-9) and General Anxiety Disorder (GAD-7) were used to evaluate symptoms of depression and anxiety, respectively. Additionally, the Self-Rating of Biological Rhythm Disorder for Adolescents (SBRDA) was used to assess status of biological rhythm disorders. Multivariate logistic regression was developed to explore factors potentially associated with symptoms of depression and anxiety stratified by academic stages. Results: Among all participants, 44.14 and 36.15% suffered from depression and anxiety symptoms, respectively. On average, participants scored 74.66 ± 19.37 on the measure of total biological rhythm disorder. Adjusted for demographic confounding factors, the logistic regression analysis showed higher scores of total biological rhythm disorder were associated with more severe depression (OR = 14.38, 95%CI: 11.38–18.16) and anxiety symptoms (OR = 11.63, 95%CI: 9.14–14.81). The similar results were also found in the stratified analysis by academic stages. Conclusions: Self-rating biological rhythm disorders are significantly associated with depression and anxiety symptoms among adolescents. Discrepancy across academic stages should also be taken into account in establishing public health strategies. [ABSTRACT FROM AUTHOR]

The field of organic photoelectrochemical transistor (OPECT) is newly emerged, with increasing efforts attempting to utilize its properties in biological sensing. Advanced materials with new physicochemical properties have proven important to this end. Herein, we report a metal-organic polymers-gated OPECT biosensing exemplified by CuⅠ-arylacetylide polymers (CuAs)-modulated poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) channel. Both the photoelectrochemical properties and gating capability of CuAs are explored and optimized for high-efficacy photogating. Morever, based on its inherent structure, the specific reaction between CuAs and sulfur ions (S2−) is revealed and S2−-mediated microRNA-21 detection is realized by linking with nucleic acid amplification and alkaline phosphatase catalytic chemistry. This work introduces metal-organic polymers as gating materials for OPECT biosensing. [Display omitted] [ABSTRACT FROM AUTHOR]

Low temperature oxidation chemistry is crucial in the auto-ignition process of internal combustion engines. The development of laboratory based reactors and diagnostic systems promotes understanding of the low temperature oxidation mechanism. This work develops a variable pressure jet-stirred reactor (VP-JSR) platform working from one to ten bar. Compared to previous high pressure studies which routinely use gas chromatography to analyze low temperature oxidation products, the difference in this work is the possibility of probing intermediates by synchrotron vacuum ultraviolet photoionization mass spectrometry via molecular beam sampling. The setup was validated by repeating n -heptane low temperature oxidation experiments at one and ten bar, respectively. Good agreement was observed between the data in this work and the data in the literature. A much more detailed species pool was probed compared to the literature study, including H 2 O 2 , carbonyl acids, alkylhydroperoxides, and keto-hydroperoxides. As a first demonstration of the usefulness of this design, the low temperature oxidation of n -heptane with initial fuel mole fraction of 0.005, residence time of 2 s, and equivalence ratio of 1.0 was studied at one, five, and ten bar. The preliminary results, including reactants, final products, and the initial low temperature oxidation intermediates, are discussed. The VP-JSR system developed in this work is valuable for study of the fuel chemistry from one to ten bar, to develop and examine chemical kinetic models, and to guide the development of the reaction system at even higher pressures, such as those in engine function and supercritical conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Doping combined with surface modification boost the performance of Fe-based cathode. • The R p of PSCFN was reduced by 32.4% through Ni doping. • The R p of PSCFN was further reduced by 56.8% after surface modification. • PrO 2 -PSCFN0.1 achieved an performance of 1190 mW·cm−2 at 800 °C. The development of cathodes with high catalytic activity and stability remains a critical challenge for the commercialization of solid oxide fuel cells (SOFCs). In this study, a novel approach combining doping and surface modification was employed to enhance the catalytic activity and CO 2 resistance of Pr 0.4 Sr 0.6 Co 0.2 Fe 0.8 O 3- δ (PSCF) cathode. Initially, Ni was partially substituted for Fe in PSCF, resulting in the reduction of the average bond energy of metal–oxygen, thereby increasing oxygen vacancy concentration and electrochemical activity. The polarization resistance of PSCFN0.1 at 800 °C was found to be 0.025 Ω·cm2, representing a 32.4 % reduction compared to PSCF. Subsequently, Pr(NO 3) 3 solution was impregnated on the surface of the PSCFN0.1 using a spin-coating technique, resulting in the formation of a PrO 2 /PSCFN0.1 heterostructure that significantly improved the oxygen reduction reaction (ORR) kinetics. At 800 °C, the polarization resistance of PrO 2 -PSCFN0.1 was only 0.016 Ω·cm2, a 56.8 % reduction compared to PSCF. Moreover, the peak power density of PrO 2 -PSCFN0.1 reached 1190 mW·cm−2 at 800 °C, representing a substantial increase of 207.4 % compared to PSCF. Furthermore, PrO 2 -PSCFN0.1-based full cell exhibited excellent performance stability and CO 2 resistance. This work provides an effective strategy to explore novel cathodes for SOFCs. [ABSTRACT FROM AUTHOR]

For intermediate-temperature solid oxide fuel cells (IT-SOFCs), high electrochemical catalytic activity and a suitable thermal expansion coefficient (TEC) are essential criteria. In this investigation, simultaneous Ca and Fe co-doped NdBa 1- x Ca x CoFeO 5+ δ (NBCCF, x = 0, 0.1, and 0.2) double-perovskites were prepared and investigated as SOFC cathode materials. The introduction of Ca and Fe effectively decreased the TECs and improved the oxygen reduction activity of the cathode. The average TEC of NdBa 0.9 Ca 0.1 CoFeO 5+δ (NBCCF1) at 30–850 °C was 19.1 × 10−6 K−1, which is decreased by 27.1 % compared to the only Fe-doped NdBaCoFeO 5+δ (NBCF). According to the distribution of relaxation time (DRT) analysis, the rate-limiting steps of the oxygen reduction reaction (ORR) include bulk diffusion and surface exchange of oxygen, and Ca doping can improve both steps. The maximum power density of the single cell with NBCCF1 as cathode reached 665 mW cm−2 at 750 °C. The polarization resistance decreased from 0.0722 to 0.0482 Ω cm2 at 800 °C. These findings indicate NBCCF1 is a viable cathode candidate for IT-SOFC. [Display omitted] • Ca and Fe co-doped NdBaCo 2 O 5+δ double perovskites were synthesized. • Ca and Fe co-doping effectively decreased the TECs of the cathode. • Ca and Fe co-doping significantly increaseed the oxygen vacancy concentration. • NBCCF1 cathode has an output power density of 665 mW cm−2 at 750 °C. [ABSTRACT FROM AUTHOR]

The reaction between phenyl radical and phenylacetylene is a prototype for the reactions of aryl radicals and alkynyl peri‑condensed aromatic hydrocarbons (PCAHs), which may help explain the dimerization of PCAHs by covalent bond with acetylene assistance. In this work, we have experimentally and theoretically investigated reaction kinetics of phenyl radical and phenylacetylene. Gas chromatography-mass spectrometry (GC–MS) is applied to separate and identify molecular structures of reaction products in a jet-stirred reactor (JSR). Diphenylacetylene is observed as the major product of this reaction, which shows dominant concentration near 1000 K. Formation of phenanthrene increases with temperature, while 9-methylene-fluorene is a minor product, and 2-ethynyl-biphenyl is negligible. The potential energy surface and rate coefficients of phenyl and phenylacetylene reaction are calculated by quantum chemistry and transition state theory. 1,2-Diphenylvinyl is the only resonance-stabilized radical (RSR) among the adducts formed via all six possible addition reaction channels. Its formation reaction channel has a much lower energy barrier and deeper potential well and, therefore, it wins the competition in the reaction of phenyl and phenylacetylene at combustion-relevant intermediate temperatures. [ABSTRACT FROM AUTHOR]

To date, the commonly used methods for diffusion coefficient measurements have some hurdles that prevent them from being widely applied in pharmaceutical laboratories. This study aimed to modify a method developed by di Cagno et al. based on the use of a UV-Vis spectrometer and apply the method to investigate the effect of dissolution media on the diffusivity of small molecules and proteins. A total of five small molecules and two proteins in different aqueous media and polymer solutions were investigated in this study. By attaching a 3D-printed cover with an open slit to a standard UV-Vis cuvette, the incident UV light could only pass through the open slit to measure the local drug concentration. During the diffusion experiment, drug molecules diffused from the cuvette bottom to the slit. According to the concentration measured as a function of time, diffusion coefficient was calculated based on Fick's law of diffusion using the analytical and numerical approaches. As a result, diffusion coefficients could be accurately measured with high reproducibility. The results also suggested that different media could affect the diffusion coefficients of small molecules by < 10% and proteins by < 15%. Since the UV-Vis spectrometer is a routine instrument, this method can potentially be employed by many pharmaceutical laboratories for diffusion coefficient measurements., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Background: The increased trends in psychological distress and mental illness have been of great significance in public health concerns. The study aimed to investigate the proportion and correlates of meeting 24-h movement guidelines (including moderate to vigorous physical activity, screen time and sleep duration) and the associations between 24-h movement guidelines met and mental well-being and psychological distress in a large sample of Chinese students., Methods: All participants received a physical examination and filled out questionnaires in this study. Chi-square tests were used to analyse the proportion of reaching 24-h guidelines by gender and logistic regression was used to analyse correlates of meeting 24-h guidelines. Two binary logistic regression models were used to analyse the association between meeting 24-h guidelines and mental well-being and psychological distress. The back-propagation artificial neural network was used to describe the importance of the independent variables., Results: The findings revealed a generally low rate of meeting the 24-h movement guidelines, particularly concerning moderate to vigorous physical activity (16.5%). Meeting all three guidelines was related to better mental health in both boys and girls. Particularly, meeting screen time guideline and meeting sleep duration guideline appeared to be more important on mental outcomes, compared to meeting moderate to vigorous physical activity guideline. Compared with boys, girls were more susceptible to the influences of 24-h movement guidelines on mental health., Conclusions: Meeting all three components of the 24-h movement guidelines was associated with the most favourable mental health outcomes for both boys and girls. Thus, maintaining a daily balance of sufficient physical activity, limited screen time, and adequate sleep is crucial for enhancing the mental health status of students., (© 2024 John Wiley & Sons Ltd.)