Search Results (51)

The environment inside subway carriages is relatively enclosed, putting passengers at risk of respiratory infections during viral pandemics such as COVID-19 and SARS. This paper uses the Euler–Lagrange method to simulate the distribution of droplet nuclei produced by coughing under six different operating conditions in a subway carriage. The study investigates the impact of different air supply characteristics and ventilation methods, including mixed ventilation (MV), floor-supply, and ceiling-return ventilation (SFRC), on the distribution of droplets. These results indicate that under MV mode, the dispersion range of droplets during a patient’s cough is the largest, with an average droplet suspension rate (SR) of up to 77% at the initial moment. The SFRC system markedly diminishes droplet dispersion, decreasing the SR by 35%. Upon increasing the air supply velocity to 0.8 m/s, the SR diminishes to 6%, the probability of particles attaining a 2 m social distance (PRP) declines by roughly 70%, and the weighted average contamination range (CR) of coughing particles reaching a safe social distance reduces by 33.5%. These results may act as a guide for the subsequent design and optimization of airflow patterns in carriages to reduce the risk of cross-infection. Full article

Obtaining robust power density through piezoelectric nanogenerators (PENGs) is very challenging. Challenges include achieving good mechanical stability, optimum stiffness, reasonable voltage generation, limited heat dissipation, and power density as needed. This work focused exactly on these areas, and hybrid filler emerged as a promising candidate among the composites studied. For example, hybrid fillers exhibited optimized properties suitable for self-powered engineering applications. The composites fabricated in this work were based on titanium oxide (TiO₂), molybdenum disulfide (MoS₂), and silicone rubber (SR) as a host matrix. The results showed that TiO₂ represents a good reinforcing filler, while MoS₂ exerts a lubricating effect, improving the composites’ mechanical strength and elongation at break. For example, the compressive modulus at 8 per hundred parts of rubber (phr) was 2.39 MPa (TiO₂), 1.62 MPa (MoS₂), and 2.1 MPa (hybrid filler). Similarly, the hysteresis loss at 5 phr was 20.09 J/m (TiO₂), 21.56 J/m (MoS₂), and 20.48 J/m (hybrid filler). Moreover, the elongation at break at 8 phr was 150% (TiO₂), 194% (MoS₂), and 170% (hybrid filler). In the same way, the electro-mechanical properties obtained were also robust. For example, the voltage output was ~22 mV (TiO₂), ~35 mV (MoS₂), and ~46 mV (hybrid filler). Moreover, the PENGs developed in this work generated power. For example, the power density was ~0.55 pW/cm² (TiO₂), ~1.03 pW/cm² (MoS₂), and ~1.56 pW/cm² (hybrid filler). Finally, the piezoelectric coefficient of the PENGs was 40 pC/N (TiO₂), 112 pC/N (MoS₂), and 160 pC/N (hybrid filler). These materials have a promising role in energy harvesting through self-powered nanogenerators for portable electronic systems. Finally, the low-power PENGs developed provide cost-effective voltage and power management circuits. This allows these PENGs to contribute to sustainable and self-sufficient electronic systems like pacemaker implants. Full article

Stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT) require precise small-field dosimetry, verified through patient-specific quality assurance (PSQA). This study evaluated the feasibility of using a single-crystal cadmium–zinc–telluride (Cd_0.9Zn_0.1Te, CZT) detector for PSQA in SRS and SBRT. We fabricated a CZT detector with Au electrodes and examined its fundamental characteristics, including dose linearity, dose rate dependence, energy dependence, angular dependence, source-to-surface distance (SSD) dependence, field size dependence, depth dependence, and reproducibility, under 6 and 10 MV LINAC beam irradiation and compared the results with those from a standard ionization chamber. The results revealed that the CZT detector demonstrated excellent linearity across 0–1000 cGy with minimal deviation in the low-dose region, negligible dose rate dependence, and minimal energy dependence, exhibiting a 2.2% drop at 15 MV relative to 6 MV. Its angular and SSD dependencies deviated slightly from the ionization chamber, consistent with the expected physical behaviors and correctable in clinical practice. The detector also revealed consistent performance over time with excellent reproducibility, and its depth dependence results were consistent with those of the ionization chamber. Thus, the CZT detector provides consistent performance in small-field measurements under varying conditions, satisfying the requirements for SRS and SBRT. Full article

Perovskites exhibit catalytic properties on the oxygen evolution reaction (OER) in water electrolysis. Elemental doping by specific preparation methods is a good strategy to obtain highly catalytical active perovskite catalysts. In this work, La_0.5Sr_0.5Co_1−xNi_xO_3−δ perovskite materials doped with different ratios of nickel were successfully synthesized by the sol-gel method. The electrochemical measurement results show that for OER in 1 M KOH solution, La_0.5Sr_0.5Co_0.8Ni_0.2O_3−δ prepared by the sol-gel method requires only a low overpotential of 213 mV to reach 10 mA cm⁻², which is significantly lower than that of La_0.5Sr_0.5Co_0.8Ni_0.2O_3−δ prepared by the hydrothermal method for the increasing about 45.24% (389 mV at 10 mA cm⁻²). In addition, La_0.5Sr_0.5Co_0.8Ni_0.2O_3−δ by the sol-gel method can be kept stable in an alkaline medium tested for 30 h without degradation. This indicates that the prepared La_0.5Sr_0.5Co_0.8Ni_0.2O_3−δ has better OER performance. The X-ray diffraction (XRD) results show that SrCO₃ is the main phase formed, which is a disadvantage of this method. The performance improvement may be affected by the carbonate phase. The scanning electron microscopy (SEM) results show that layer structured La_0.5Sr_0.5Co_0.8Ni_0.2O_3−δ by the sol-gel method has more surface pores with a pore diameter of about 0.362 μm than spherical granular structured La_0.5Sr_0.5Co_0.8Ni_0.2O_3−δ by the hydrothermal method. X-ray photoelectronic spectroscopy (XPS) results reveal that the crystal lattice of La_0.5Sr_0.5Co_0.8Ni_0.2O_3−δ by nickel doping is lengthened, and the electronic configuration of Co is also changed by the sol-gel preparation process. The improved electrocatalytic performance of La_0.5Sr_0.5Co_0.8Ni_0.2O_3−δ may be attributed to the pore structure formed providing more active sites during the sol-gel process and the improved oxygen mobility with Ni doping by the sol-gel method. The doping strategy using the sol-gel method provides valuable insights for optimizing perovskite catalytic properties. Full article

Aims: Atrial fibrillation (AF) is the most common chronic/recurrent arrhythmia, which significantly impairs quality of life and increases cardiovascular morbidity and mortality. Therefore, the aim of the present study was to investigate the properties of three repolarizing potassium currents which were shown to contribute to AF-induced electrical remodeling, i.e., the transient outward (I_to), inward rectifier (I_K1) and acetylcholine-sensitive (I_K,ACh) potassium currents in isolated atrial myocytes obtained from dogs either with sinus rhythm (SR) or following chronic atrial tachypacing (400/min)-induced AF. Methods: Atrial remodeling and AF were induced by chronic (4–6 weeks of) right atrial tachypacing (400/min) in dogs. Transmembrane ionic currents were measured by applying the whole-cell patch-clamp technique at 37 °C. Results: The I_to current was slightly downregulated in AF cells when compared with that recorded in SR cells. This downregulation was also associated with slowed inactivation kinetics. The I_K1 current was found to be larger in AF cells; however, this upregulation was not statistically significant in the voltage range corresponding with atrial action potential (−80 mV to 0 mV). I_K,ACh was activated by the cholinergic agonist carbachol (CCh; 2 µM). In SR, CCh activated a large current either in inward or outward directions. The selective I_K,ACh inhibitor tertiapin (10 nM) blocked the outward CCh-induced current by 61%. In atrial cardiomyocytes isolated from dogs with AF, the presence of a constitutively active I_K,ACh was observed, blocked by 59% with 10 nM tertiapin. However, in “AF atrial myocytes”, CCh activated an additional, significant ligand-dependent and tertiapin-sensitive I_K,ACh current. Conclusions: In our dog AF model, I_to unlike in humans was downregulated only in a slight manner. Due to its slow inactivation kinetics, it seems that I_to may play a more significant role in atrial repolarization than in ventricular working muscle myocytes. The presence of the constitutively active I_K,ACh in atrial myocytes from AF dogs shows that electrical remodeling truly developed in this model. The I_K,ACh current (both ligand-dependent and constitutively active) seems to play a significant role in canine atrial electrical remodeling and may be a promising atrial selective drug target for suppressing AF. Full article

Sugarcane mosaic virus (SCMV), sugarcane streak mosaic virus (SCSMV), and sorghum mosaic virus (SrMV) are the causative pathogens of mosaic disease. This study aimed to identify mosaic virus infection and its impact on photosynthetic and antioxidant gene expression in eight commercial sugarcane cultivars grown on sugarcane plantations in East Java, Indonesia. The disease incidence and severity were observed in symptomatic leave samples, and then the virus was identified. A high incidence and severity of mosaic symptoms were observed in the PS881 and NX04 cultivars compared with the other cultivars. RT-PCR analysis detected SCSMV infection in all cultivars; double infections with SCSMV and SCMV in the PS881, PS882, and Cening cultivars; and triple infections with SCSMV, SCMV, and SrMV in the PS881 cultivar. Ascorbate peroxidase (Apx) expression was upregulated in all virus-infected cultivars and significantly increased in the triple-infected PS881 cultivar. However, catalase (Cat) expression was only slightly increased in the PS881 cultivar. The chlorophyll content was reduced, and the PsaA gene was downregulated in all cultivars. The expression of PsaA, RbcS, and Sps was significantly suppressed in the triple-infected PS881 cultivar. Moreover, the downregulation of both the RbcS and Pepc genes was concomitant with that of their protein levels. Full article

In the field of endoscopic imaging, challenges such as low resolution, complex textures, and blurred edges often degrade the quality of 3D reconstructed models. To address these issues, this study introduces an innovative endoscopic image super-resolution and 3D reconstruction technique named Omni-Directional Focus and Scale Resolution (OmDF-SR). This method integrates an Omnidirectional Self-Attention (OSA) mechanism, an Omnidirectional Scale Aggregation Group (OSAG), a Dual-stream Adaptive Focus Mechanism (DAFM), and a Dynamic Edge Adjustment Framework (DEAF) to enhance the accuracy and efficiency of super-resolution processing. Additionally, it employs Structure from Motion (SfM) and Multi-View Stereo (MVS) technologies to achieve high-precision medical 3D models. Experimental results indicate significant improvements in image processing with a PSNR of 38.2902 dB and an SSIM of 0.9746 at a magnification factor of ×2, and a PSNR of 32.1723 dB and an SSIM of 0.9489 at ×4. Furthermore, the method excels in reconstructing detailed 3D models, enhancing point cloud density, mesh quality, and texture mapping richness, thus providing substantial support for clinical diagnosis and surgical planning. Full article

Quality assurance (QA) ensures the accurate and safe delivery of radiation treatment. However, there are several challenges for advanced radiotherapy techniques, such as stereotactic radiosurgery (SRS), where substantial doses of radiation with multi-directional beams and variable dose rates are delivered to specific areas. Current dosimeters lack high precision, exhibiting issues with dependency on the angle of measurement and the dose rate. This study investigates the characterization of a two-dimensional edgeless silicon diode array for QA in SRS. This detector underwent evaluation of its dose linearity, percentage depth dose (PDD), output factors (OFs), dose rate variability, and angular dependence with megavoltage linear accelerator beams. The edgeless array demonstrated a linear response in the direct detection of MV therapeutic X-rays with sensitivity of 6.95 × 10⁻³ ± 2.3 × 10⁻⁵ Gy/nC, and the percentage differences for PDD and OF measurements were found to be within 2% compared to the reference detector. A dose per pulse dependence of ±2% was demonstrated across the range of 0.12 to 0.39 mGy/pulse. The angular dependence was within 2% variation for irradiation angles greater than 80° and smaller than 120°; however, a maximum of 4% variation was observed with some diodes for angles between 80° and 120°. The improved performance of the edgeless array is likely to overcome limitations of the current dosimeters for SRS QA by operating without the need of any corrections. Full article

Sorghum mosaic virus (SrMV) is one of the most prevalent viruses deteriorating sugarcane production. Salicylic acid (SA) plays an essential role in the defense mechanism of plants and its exogenous application has been observed to induce the resistance against biotic and abiotic stressors. In this study, we set out to investigate the mechanism by which sorghum mosaic virus (SrMV) infected sugarcane responds to SA treatment in two sugarcane cultivars, i.e., ROC22 and Xuezhe. Notably, significantly low viral populations were observed at different time points (except for 28 d in ROC22) in response to post-SA application in both cultivars as compared to control based on qPCR data. Furthermore, the lowest number of population size in Xuezhe (20 copies/µL) and ROC22 (95 copies/µL) was observed in response to 1 mM exogenous SA application. A total of 2999 DEGs were identified, of which 731 and 2268 DEGs were up- and down-regulated, respectively. Moreover, a total of 806 DEGs were annotated to GO enrichment categories: 348 biological processes, 280 molecular functions, and 178 cellular components. GO functional categorization revealed that DEGs were mainly enriched in metabolic processes, extracellular regions, and glucosyltransferase activity, while KEGG annotation revealed that DEGs were mainly concentrated in phenylpropanoid biosynthesis and plant-pathogen interaction suggesting the involvement of these pathways in SA-induced disease resistance of sugarcane in response to SrMV infection. The RNA-seq dataset and qRT-PCR assay showed that the transcript levels of PR1a, PR1b, PR1c, NPR1a, NPR1b, PAL, ICS, and ABA were significantly up-regulated in response to SA treatment under SrMV infection, indicating their positive involvement in stress endorsement. Overall, this research characterized sugarcane transcriptome during SrMV infection and shed light on further interaction of plant-pathogen under exogenous application of SA treatment. Full article

Producing oxygen and hydrogen via the electrolysis of water has the advantages of a simple operation, high efficiency, and environmental friendliness, making it the most promising hydrogen production method. In this study, La_0.2Sr_0.8Cu_0.4Co_0.6O_3−δ (LSCC) nanofibers were prepared by electrospinning to utilize non-noble perovskite oxides instead of noble metal catalysts for the oxygen evolution reaction, and the performance and electrochemical properties of LSCC nanofibers synthesized at different firing temperatures were evaluated. In an alkaline environment (pH = 14, 6 M KOH), the nanofibers calcined at 650 °C showed an overpotential of 209 mV at a current density of 10 mA cm⁻² as well as good long-term stability. Therefore, the prepared LSCC-650 NF catalyst shows excellent potential for electrocatalytic oxygen evolution. Full article

Sorghum mosaic virus (SrMV, the genus Potyvirus of the family Potyviridae) is a causal agent of common mosaic in sugarcane and poses a threat to the global sugar industry. In this study, a total of 901 sugarcane leaf samples with mosaic symptom were collected from eight provinces in China and were detected via RT-PCR using a primer pair specific to the SrMV coat protein (CP). These leaf samples included 839 samples from modern cultivars (Saccharum spp. hybrids) and 62 samples from chewing cane (S. officinarum). Among these, 632 out of 901 (70.1%) samples were tested positive for SrMV. The incidences of SrMV infection were 72.3% and 40.3% in modern cultivars and chewing cane, respectively. Phylogenetic analysis showed that all tested SrMV isolates were clustered into three clades consisting of six phylogenetic groups based on 306 CP sequences (this study = 265 and GenBank database = 41). A total of 10 SrMV isolates from South America (the United States and Argentina) along with 106 isolates from China were clustered in group D, while the remaining 190 SrMV isolates from Asia (China and Vietnam) were dispersed in five groups. The SrMV isolates in group F were limited to Yunnan province in China, and those in group A were spread over eight provinces. A significant genetic heterogeneity was elucidated in the nucleotide sequence identities of all SrMV CPs, ranging from 69.0% to 100%. A potential recombination event was postulated among SrMV isolates based on CP sequences. All tested SrMV CPs underwent dominant negative selection. Geographical isolation (South America vs. Asia) and host types (modern cultivars vs. chewing cane) are important factors promoting the genetic differentiation of SrMV populations. Overall, this study contributes to the global understanding of the genetic evolution of SrMV and provides a valuable resource for the epidemiology and management of the mosaic in sugarcane. Full article

Type-2 ryanodine receptor (RyR2) is the major Ca²⁺ release channel of the cardiac sarcoplasmic reticulum (SR) that controls the rhythm and strength of the heartbeat, but its malfunction may generate severe arrhythmia leading to sudden cardiac death or heart failure. S4938F-RyR2 mutation in the carboxyl-terminal was expressed in human induced pluripotent stem cells derived cardiomyocytes (hiPSC-CMs) using CRISPR/Cas9 gene-editing technique. Ca²⁺ signaling and electrophysiological properties of beating cardiomyocytes carrying the mutation were studied using total internal reflection fluorescence microscopy (TIRF) and patch clamp technique. In mutant cells, L-type Ca²⁺ currents (I_Ca), measured either by depolarizations to zero mV or repolarizations from +100 mV to –50 mV, and their activated Ca²⁺ transients were significantly smaller, despite their larger caffeine-triggered Ca²⁺ release signals compared to wild type (WT) cells, suggesting I_Ca-induced Ca²⁺ release (CICR) was compromised. The larger SR Ca²⁺ content of S4938F-RyR2 cells may underlie the higher frequency of spontaneously occurring Ca²⁺ sparks and Ca²⁺ transients and their arrhythmogenic phenotype. Full article

Electro-mechanical configurations can be piezo-electric transducers, triboelectric generators, electromagnetic induction, or hybrid systems. Our present study aims at developing energy generation through the piezoelectric principle. Gel-type soft SR with Shore A hardness below 30 was used as a versatile material for an elastomeric substrate. Also, multi-wall carbon nanotube (MWCNT), and diatomaceous earth (DE) were used as reinforcing fillers. This “gel-type” soft SR has crosslinking polymer networks with silicone encapsulated within its structure. Mechanical properties such as modulus or stretchability are of utmost importance for such devices based on “gel-type” soft. From the experiments, some of the mechanical aspect’s values are summarized. For example, the stretchability was 99% (control) and changes to 127% (3 phr, MWCNT), 76% (20 phr DE), and 103% (20 phr hybrid). From electro-mechanical tests, the output voltage was 0.21 mV (control) and changed to 0.26 mV (3 phr, MWCNT), 0.19 mV (20 phr DE), and 0.29 mV (20 phr hybrid). Moreover, from real-time biomechanical human motion tests in “gel-type” soft-based composites, a relationship among output voltage from machine to human motions was established. Overall, these configurations make them promising against traditional portable devices such as batteries for small power applications such as mobile phones. Full article

Sorghum mosaic virus (SrMV) causes sugarcane mosaic disease and has significant adverse economic impacts on the cultivation of sugarcane. This study aimed to develop a rapid isotherm nucleic acid amplification method for detecting SrMV. Specific primers were designed to target the conserved region of the P3 gene of SrMV. The reverse transcription recombinase-aided amplification (RT-RAA) method was developed by screening primers and optimizing reaction conditions. Comparative analyses with RT-PCR demonstrated that the RT-RAA method exhibited superior specificity, sensitivity, and reliability for SrMV detection. Notably, using a standard plasmid diluted 10-fold continuously as a template, the sensitivity of RT-RAA was 100-fold higher than that of RT-PCR. Moreover, the RT-RAA reaction displayed flexibility in a temperature range of 24–49 °C, eliminating the need for expensive and complex temperature control equipment. Thus, this method could be utilized at ambient or even human body temperature. Within a short duration of 10 min at 39 °C, the target sequence of SrMV could be effectively amplified. Specificity analysis revealed no cross-reactivity between SrMV and other common sugarcane viruses detected via the RT-RAA. With its high sensitivity, rapid reaction time, and minimal equipment requirements, this method presents a promising diagnostic tool for the reliable and expedited detection of SrMV. Furthermore, it indicates broad applicability for successfully detecting other sugarcane viruses. Full article

The aim of this study was to identify the relationship between dry-land and in-water strength with performance and kinematic variables in short-distance, middle-distance, and repeated sprint swimming. Fifteen competitive swimmers applied a bench press exercise to measure maximum strength (MS), maximum power (P), strength corresponding to P (F@P), maximum velocity (MV), and velocity corresponding to P (V@P) using F–V and P–V relationships. On a following day, swimmers performed a 10 s tethered swimming sprint (TF), and impulse was measured (IMP). On three separate days, swimmers performed (i) 50 and 100 m, (ii) 200 and 400 m, and (iii) 4 × 50 m front crawl sprint tests. Performance time (T), arm stroke rate (SR), arm stroke length (SL), and arm stroke index (SI) were calculated in all tests. Performance in short- and middle-distance tests and in 4 × 50 m training sets were related to dry-land MS, P, TF, and IMP (r = 0.51–0.83; p < 0.05). MS, P, and TF were related to SR in 50 m and SI in 50 and 100 m (r = 0.55–0.71; p < 0.05). A combination of dry-land P and in-water TF variables explains 80% of the 50 m performance time variation. Bench press power and tethered swimming force correlate with performance in short- and middle-distance tests and repeated sprint swimming. Full article