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Abstract The current research on noncircular hobbing mainly focuses on the linkage model and motion realization. However, the intermittent cutting characteristics of hobbing would increase uncertainties in the manufacturing process. In this paper, a hobbing machining model with tool-shifting characteristics was proposed to solve the problems of cutting force fluctuation and inconsistency of tooth profile envelope accuracy at different positions of the pitch curve in noncircular gear hobbing. Based on the unit cutting force coefficient method, the undeformed chip volume generated by interrupted cutting was used to characterize the fluctuation trend of the hobbing force. The fluctuation characteristics of the cutting force generated by different hobbing models were compared and analyzed. Using the equivalent gear tooth and hob slotting numbers, an analysis model of the tooth profile envelope error of the noncircular gear was constructed. Subsequently, the tooth profile envelope errors at different positions of the pitch curve were compared and analyzed based on the constructed model. The transmission structure of the electronic gearbox was constructed based on the proposed hobbing model, and the hobbing experiment was conducted based on the self-developed noncircular gear CNC hobbing system. This paper proposes a hobbing method that can effectively suppress the fluctuation of the peak and whole circumference cutting force and reduce the maximum envelope error of the whole circumference gear teeth.

Topological modification of gear surface is used to achieve better meshing transmission performance and accuracy. However, in the traditional gear modification grinding process, the topological modified tooth surface is usually simplified to the control of profile modification and lead modification, which is difficult to achieve the coincidence of machining and design. To solve this problem, a flexible topology flank modification method based on polynomial interpolation function is proposed in this paper. Based on the gear meshing principle and polynomial interpolation technology, the method realizes a topological modification of the gear by controlling multiple axes’s position on the machine tool. Firstly, a gear grinding model of worm grinding wheel with controllable grinding precision is established. Then the axial, radial and tangential motions of worm grinding wheel is expressed as fifth order polynomials, and the polynomial coefficients is optimized by particle swarm optimization algorithm. Finally, numerical simulation was used to compare the proposed method with the sensitivity matrix method, and the results showed that the proposed method had better optimization effect. The new flexible topological modification method can realize the topological modification machining by controlling the motion of each axis of the tool, and the problem that the topological modification machining does not match the design is solved.

Squirrels of temperate zones commonly store nuts or seeds under leaf litter, in hollow logs, or even in holes in the ground; however, in the humid rainforests of Jianfengling in Hainan, South China, we show that some flying squirrels cache elliptical or oblate nuts by hanging them securely in vegetation. These small flying squirrels were identified as Hylopetes phayrei electilis (G. M. Allen, 1925) and Hylopetes alboniger (Hodgson, 1870), in video clips captured of their behavior around focal nuts. Squirrels chewed grooves encircling ellipsoid nuts or distributed on the bottoms of oblate nuts, and then used these grooves to fix nuts tightly between small twigs 0.1–0.6 cm in diameter that were connected at angles of 25–40°. The grooves carved on the nuts (concave structure) connected with Y-shaped twigs (convex structure) and thus firmly affixed the nuts to the plant in a way similar to a mortise-tenon joint used in architecture and carpentry. Cache sites were on small plants located 10–25 m away from the closest potentially nut-producing tree, a behavior that likely reduces the discovery and consumption of the nuts by other animals. The adaptive squirrel behavior that shapes and fits nuts between twigs seems to be directed at providing more secure storage that increases food supply during dry periods in a humid tropical rainforest. In addition to providing such benefits for the squirrels, we suggest that this behavior also impacts the distribution of tree species in the forest.

Intracranial hemorrhage (ICH), the second most common subtype of stroke, exacerbates the disruption of the blood-brain barrier (BBB), leading to vasogenic edema, plasma protein extravasation, and infiltration of neurotoxic substances. The clearance capacity of the brain plays a crucial role in maintaining BBB homeostasis and facilitating patient recovery after hemorrhage. This study aimed to investigate the effect of circadian rhythms on BBB function, neuronal damage, and clearance capabilities. The transwell model and hemoglobin were co-cultured to simulate the BBB environment after ICH. After intervention with different light groups, neuronal apoptosis was determined, glial phagocytosis was analyzed, the expression of endogenous clearing-related proteins aquaporin 4 (AQP4) and low-density lipoprotein receptor-related protein 1 (LRP1) was detected by western blotting and immunofluorescence dual standard method, and the expression of the tight junction protein occludin and melatonin receptor 1A (MTNR1A) was quantitatively analyzed. Circadian rhythms play a key role in maintaining the integrity of the BBB, reducing oxidative stress-induced neuronal damage, and improving microglial phagocytosis. Meanwhile, the expression of occludin and MTNR1A in neurovascular unit (NVU) co-cultured with hemoglobin improved the expression of AQP4 and LRP1, the key proteins in the NVU's endogenous brain clearance system. Circadian rhythm (alternating black and white light) protects the NVU BBB function after ICH, promotes the expression of proteins related to the clearance of the hematoma, provides new evidence for the clinical treatment of patients recovering from ICH, and improves the circadian rhythm to promote brain metabolism and hematoma clearance. [ABSTRACT FROM AUTHOR]

Gear flank twist occurs when threaded wheel grinds crowning lead modified helical gears, which reduces gear machining accuracy. To overcome this problem, a flank twist compensation method based on flexible electronic gearbox is proposed in this paper, the method can reduce the degree of twist and improve gear machining accuracy. Firstly, flank equations of gear and threaded wheel are established, coordinates and normal vectors of gear flank are used to represent twist. Secondly, coordinate transformation matrix between workpiece and tool coordinate system is established based on multi-body system theory and homogeneous coordinate transformation, and relationship between coordinates and normal vectors of gear flank and master-slave axis (B-axis, C-axis, X-axis, Y-axis, Z-axis) movement amount is obtained by inverse kinematics and electronic gearbox, then master-slave axis movement compensation amount between crowning lead modified flank and twisted flank is obtained. Finally, twist is compensated by compensating for master-slave axis movement amount, and flank contact analysis based on KISSsoft is carried out to observe normal force and contact stress of flanks. This paper uses inverse kinematics and electronic gearbox to realize flank twist compensation, which makes up for long period and high cost of traditional flank twist compensation by changing shape of threaded wheel. Simulation results show that this method can effectively compensate for flank twist and improve accuracy and efficiency when threaded wheel grinds crowning lead modified helical gears.

Seeds from two odd-polyploid Ulmus americana L., both open-pollinated from surrounding tetraploid trees, were analyzed for nuclear genome size by using flow cytometry. Seeds from the triploid were predominantly aneuploid, with DNA content intermediate between triploid and tetraploid levels, but substantial numbers of tetraploid and pentaploid seeds were observed. No seeds of even ploidy were found in progeny of the pentaploid; seeds of the pentaploid were pentaploid, aneuploid with DNA content intermediate between tetraploid and pentaploid levels, or aneuploid with DNA content intermediate between pentaploid and hexaploid levels. Seeds from both trees often gave two peaks via flow cytometry, indicating the presence of two genetically distinct embryos in the same seed. The frequency of polyembryony in the sample is much higher than the frequency of seeds that yield multiple seedlings, suggesting that the formation of two genetically distinct embryos, followed by abortion of one embryo, is common in elms.

Extensive and high residue variations in enrofloxacin (ENR) exist in different aquatic products. A novel quantitative method for measuring ENR using high-performance liquid chromatography–tandem mass spectrometry was developed employing enrofloxacin-d5 (ENR-d5) and enrofloxacin-d3 (ENR-d3) as isotope surrogates. This reduced the deviation of detected values, which results from the overpass of the linear range and/or the large difference in the residue between the isotope standard and ENR, from the actual content. Furthermore, high residue levels of ENR can be directly diluted and re-calibrated by the corresponding curve with the addition of high levels of another internal surrogate without repeated sample preparation, avoiding the overflow of the instrument response. The validation results demonstrated that the method can simultaneously determine ENR residues from MQL (2 µg/kg) to 5000 × MQL (method quantification limit) with recoveries between 97.1 and 106%, and intra-precision of no more than 2.14%. This method realized a wide linear calibration range with dual deuterated isomers, which has not been previously reported in the literature. The developed method was successfully applied to the analysis of ENR in different aquatic products, with ENR residue levels varying from 108 to 4340 μg/kg and an interval of precision in the range of 0.175~6.72%. These results demonstrate that batch samples with a high variation in ENR residues (over the linear range with a single isotope standard) can be detected by the dual isotope surrogates method in a single sample preparation process.

This paper proposes a method to study the machining error when one is generating gear grinding based on the mapping relationship between the grinding wheel surface and the tooth flank. The profile of the grinding wheel after grinding is collected, and the theoretical tooth flank is derived according to a model of generating gear grinding. By comparing the normal deviation of the theoretical tooth flank with the measured tooth flank, the machining error characteristics are identified. Firstly, the mathematical model of generating gear grinding is established according to a multi-body theory and coordinate transformation. Secondly, the experiments of the lead modification for helical gear were performed on a YW7232 CNC gear grinding machine. The tooth flank twist compensation function was turned off in experiments No. 1–No. 3, and it was turned on in experiments No. 4–No. 6, while the other process parameters kept the same. Then, the corresponding theoretical tooth flank data were derived from the grinding wheel surface which were measured using the laser profilometer LJ-V7000. Finally, the machining error characteristics were obtained by analyzing the difference between the theoretical and measured tooth flank deviations. The result of this paper can provide theoretical and practical references for the improvement of the gear grinding accuracy and gear modification design.

Mosquitoes historically threatened human health; the major mosquito-related global health issues include malaria, dengue fever, yellow fever, and Zika, as well as several other vector-borne outbreaks. Here, the EtOAc extract of the mangrove sediment fungus Penicillium brefeldianum ABC190807 exerted larvicidal activities against the third instar larvae of Aedes aegypti with an LC50 of 0.089 mg/mL. One new purinyl-steroid (ergosta-4,6,8(14),22-tetraen-3-(6-amino-9H-purin-9-yl) (1)), along with six (2–7) known compounds, were isolated from the EtOAc extract of Penicillium brefeldianum ABC190807. Structures of the compounds were elucidated via 1D/2D NMR and HR-ESI-MS data. Respective spectral data were compared with those of known compounds. Among all compounds whose larvicidal activity against the third instar larvae of Aedes aegypti was evaluated, compounds 2 and 7 showed larvicidal activity with respective LC50 values of 0.452 and 0.337 mg/mL.

To improve the stability and accuracy of non-circular gear transmission, a beveloid non-circular gear transmission scheme was developed to reduce the meshing impact and achieve backlash adjustment. When using the beveloid rack as the medium, the instantaneous contact line of the beveloid non-circular gear pair was shown to be a straight line, and the tooth surface was shown to be a ruled surface based on the transmission relationship between the rack centerline and the non-circular pitch curve. The zero-modification method was employed to develop the beveloid non-circular gear. Further, the generation method for the tooth profile of the modified non-circular gear was reviewed, and a digital solid model was developed for the beveloid non-circular gear. The physical contact simulation method was used to analyze the meshing backlash, and the influence of the axial displacement adjustment on the meshing backlash of the gear pair was obtained. By considering a pair of beveloid elliptic gears as an example, machining and transmission experiments were conducted, with results showing smooth gear-pair meshing and the anticipated backlash adjustment effect.

In the silicone material extrusion (MEX) process, product profile error and performance defects are common problems due to changes in strand shape. A process optimization method considering strand morphology, denoted as SMO, which allows adjustment of the strand shape by adjusting process parameters during the printing process is presented. The relation between process parameters (extrusion speed, moving speed, nozzle height, and nozzle radius) and the geometric parameters (strand width and strand height) of the cross-section, as well as the relationship between strand spacing, layer height, and process parameters in no void constraint is discussed and verified. SMO was utilized to produce specimens with tunable strand width and strand height. Tensile tests and profile scans were performed to compare SMO with other methods to verify its feasibility. Specimens fabricated using the SMO method have up to a 7% increase in tensile strength, up to a 10% reduction in processing time, and about a 60% reduction in strand height error over unused ones. The results show that the SMO method with adjustable strand width can effectively balance efficiency and mechanical properties compared to uniform infill, and the SMO method with adjustable strand height can provide higher accuracy compared to uniform strand height. The proposed method is validated and improves the efficiency and accuracy of silicone MEX.

In the Asian corn borer (ACB), Ostrinia furnacalis (Guenée), diapause is governed by a multigenetic constitution that responds to daylength and temperature with seasonality. The ACB displays uni- or multivoltinism, depending on its geographic specificity. Hence, warmer temperatures may result in alternation of voltinism in the ACB, which will help in understanding the ecological consequences of climate warming on insects. In the present study, we investigated the voltinism in two natural populations from Harbin (H) and Gongzhuling (G) as well as a laboratory (L) population (established from the H population in 2017) of the ACB, at ambient and elevated atmospheric CO2 (aCO2 390 μL/L and eCO2 750 μL/L) and temperature (aT and Et = At + 2 °C). From the diapause response, both the uni- and multivoltine ecotypes were coexisting in the H population. The neonate occurrence date of 50% individuals that induced diapause was ca. 10 days later in the G population than in the H population, but it was about 10 days earlier than in the L population. Comparing to the dates of onset and the peak of diapause induction, the G and L populations were less variable than the H population in response to a short and/or shortening daylength in the field. The univoltine individuals could not be eliminated completely after 19 generations of selection. Diapause incidence decreased with a climate-warming scenario, which was temporally specific and could be overridden by significantly low daily average temperatures. The eCO2 did not directly impact the voltinism. On the basis of voltinism, the H population was sympatric for uni- and multivoltine ecotypes, with multivoltinism being dominant. The univoltinism trait was recessive. Climate warming could significantly override the effect of photoperiod, which was yearly dependent. Warmer temperatures and a decreased latitude (shortened daylength), and their interaction, would drive ACB evolution toward diapause homogeneity for multivoltinism.

Background:. Obstructive sleep apnea (OSA) syndrome has a negative impact on the health of millions of adolescents and youth. The aim of this study was to evaluate the associations of OSA syndrome with obesity and cardiometabolic risk factors among adolescents and youth at risk for metabolic syndrome (MS). Methods:. A total of 558 subjects aged 14-28 years were recruited from the Beijing Child and Adolescent Metabolic Syndrome Study. Each underwent a 2-h oral glucose tolerance test (OGTT), echocardiography, and liver ultrasonography. Anthropometric measures, blood levels of glucose, lipids, and liver enzymes were assessed. Subjects with high or low risk for OSA were identified by Berlin Questionnaire (BQ). Results:. Among the subjects in obesity, 33.7% of whom were likely to have OSA by BQ. Subjects with high risk for OSA had higher neck and waist circumference and fat mass percentage compared to those with low risk for OSA (P < 0.001). Moreover, significant differences in levels of lipids, glucose after OGTT, and liver enzymes, as well as echocardiographic parameters were found between the two groups with high or low risk for OSA (P < 0.05). The rates of nonalcoholic fatty liver disease (71.0% vs. 24.2%), MS (38.9% vs. 7.0%), and its components in high-risk group were significantly higher than in low-risk group. Conclusions:. The prevalence of OSA by BQ was high in obese adolescents and youth. A high risk for OSA indicates a high cardiometabolic risk. Mechanisms mediating the observed associations require further investigation.

Both adenosine triphosphate (ATP) and glucose are important to human health, and their abnormal levels are closely related to angiocardiopathy and hypoglycaemia. Therefore, the simultaneous determination of ATP and glucose with a single test mode is highly desirable for disease diagnostics and early recognition. Herein, a new fluorescence on/off switch sensing platform is developed by carbon nanodots (CNDs) to detect ATP and glucose simultaneously. The fluorescence of CNDs can be quenched by Cu2+ and hydrogen peroxide (H2O2), due to the formation of hydroxyl radicals (·OH) produced in the Cu-Fenton reaction. Based on the high affinity of Cu2+ with ATP, the fluorescence of CNDs will recover effectively after adding ATP. Additionally, glucose can be efficiently catalyzed by glucose oxidase (GOx) to generate H2O2, so the platform can also be utilized to analyze glucose. Under optimum conditions, this sensing platform displays excellent sensitivity and the linear ranges are from 0.1 to 7 μM for ATP with a limit of detection (LOD) of 30.2 nM, and from 0.1 to 7 mM for glucose with a LOD 39.8 μM, respectively. Benefiting from the high sensitivity and selectivity, this sensing platform is successfully applied for simultaneous detection of ATP and glucose in human serum samples with satisfactory recoveries.

Currently, functional single-stranded oligonucleotide probes, termed aptamers, generated by an iterative technology, Systematic Evolution of Ligands by Exponential Enrichment (SELEX), are utilized to selectively target molecules or cells with high affinity. Aptamers hold considerable promise as multifunctional molecules or conjugates for challenging nanotechnologies or bioapplications now and in the future. In this review, we first describe recent endeavors to select aptamers towards live cancer cells via cell-SELEX. We then introduce several characteristic applications of selected aptamers, especially in imaging, drug delivery and therapy. In part, these advances have been made possible via synthesis of aptamer-based nanomaterials, which, by their sizes, shapes, and physicochemical properties, allow such aptamer-nanomaterial complexes to function as signal reporters or drug carriers. We also describe how these aptamer-based molecular tools contribute to cancer biomarker discovery through high-affinity recognition of membrane protein receptors.

Purpose: Type 2 diabetes mellitus (T2DM) is a common risk factor for cardiovascular disease which increases the risk of heart failure. This study aimed to determine whether clinical characteristics and subclinical cardiovascular disease (CVD) features are correlated with echocardiographic morpho-functional parameters of T2DM patients. Patients and Methods: Two hundred and fifty-five T2DM patients without a history of coronary heart disease were enrolled in this cross-sectional study. The demographic characteristics, glucose and lipid levels were assessed for each patient. Carotid ultrasonography and peripheral artery examination were performed to measure carotid intima-media thickness (cIMT), carotid plaque, ankle-brachial index (ABI), brachial artery pulse wave velocity (baPWV), and carotid-femoral pulse wave velocity (cfPWV). Furthermore, echocardiography was conducted to evaluate cardiac morphology and systolic and diastolic function. The relationship between clinical characteristics, subclinical cardiovascular diseases, and cardiac morpho-functional parameters was explored with the Pearson and stepwise multivariable linear regression analyses. Results: A total of 255 subjects aged 18– 80 years were enrolled in the study. Multiple regression analysis revealed that left ventricular mass index (LVMI) was correlated with age (β=0.463, p = 0.000) and systolic blood pressure (SBP) (β=0.179, p = 0.003). Relative wall thickness (RWT) was related to cfPWV (β=0.006, p = 0.007) and homeostasis model assessment of insulin resistance (HOMA-IR) (β=0.000, p = 0.036). In contrast, left ventricular ejection fraction (LVEF) was inversely related to cIMT (β=− 0.925, p = 0.019). The ratio of the peak flow velocity of early diastole to atrial contraction (peak E/A) was correlated with age (β=− 0.014, p = 0.000), diastolic blood pressure (DBP) (β=− 0.006, p = 0.001) and cfPWV (β=− 0.025, p = 0.044). Conclusion: In preclinical stage A/B heart failure adults with T2DM, age, BP, HOMA-IR, cfPWV and cIMT are correlated with cardiac morpho-functional parameters. [ABSTRACT FROM AUTHOR]

In traditional processing, a large number of G01 blocks are adopted to discretize free surface or curve for NC machining. But, the continuity of G01 line segments is only C0, which may lead to discontinuity of axis acceleration, resulting in the frequent fluctuation of tool motion at the junctions in high-speed machining, deteriorating the quality of work piece, and reducing processing efficiency. To solve this problem, a local smoothing interpolation method is proposed in this paper. At first, the analytic relationship between the continuity of the trajectory and the continuity of the axes motion is first systematically described by formula. Based on this relationship, a local smoothing algorithm and a feed-rate scheduling method are proposed to generate a C2 continuous tool path motion with axis-acceleration continuity. The local smoothing algorithm smoothes the corners of G01 blocks by the cubic B-spline according to the cornering error tolerance specified by the user. After the feed rate at critical points of smoothed tool path was determined by a modified bidirectional scanning algorithm by considering constrains of chord error and kinematic property, an iterative S-shape feed rate scheduling is employed to minimize residual distance caused by round of time while ensuring the continuity of feed rate and acceleration. Then, a look-ahead interpolation strategy combined with smoothing algorithm and feed-rate scheduling as mentioned is proposed for real-time interpolation of short line segments. At last, simulations are conducted to verify the effectiveness of the proposed methods. Compared with the traditional G01 interpolation, it can significantly improve the processing efficiency and shorten the processing time within error tolerance. [ABSTRACT FROM AUTHOR]

Elms (Ulmus spp.) are iconic street and landscape trees, but their use is currently limited by susceptibility to disease, especially Dutch elm disease (DED). Improved access to disease-resistant germplasm will be of great benefit for ongoing breeding and selection programs, but these programs have been limited historically by uncertain relationships among Ulmus species, especially the North American species and their putative Old World relatives. Estimates of genome size from 28 species representing both subgenera of Ulmus (subg. Ulmus and subg. Oreoptelea) and six species in the related small genera Zelkova, Hemiptelea, and Planera were estimated using flow cytometry. Genome-size estimates were calibrated using seven elms with known chromosome counts. Results strongly supported the subgeneric classification of Wiegrefe et al. Monoploid genome size was found to be quite constant within the subgenera of Ulmus they recognized and within the small genera, and polyploidy is uncommon in these plants. However, there are consistent differences in genome size between the subgenera of Ulmus and between them and the smaller genera, and these differences can be used to place species in their proper taxon, knowledge which can be useful in identifying disease-resistant germplasm that may be compatible with Ulmus americana and other North American taxa. Two Asian species that have sometimes been considered to be related to North American species now placed in subg. Oreoptelea were tested. The Himalayan Ulmus villosa has a much smaller genome than either of the subgenera, indicating that its relationship with other elms is rather remote. It may be a source of novel genes in Ulmus, but our results indicate it is not close to U. americana or other New World species. In contrast, results from the rare Chinese species Ulmus elongata support its placement in subg. Oreoptelea. It is the only close relative of the North American elms that is native to Asia, where DED is believed to have originated, and its response to DED infection should be evaluated. [ABSTRACT FROM AUTHOR]

Objective. To investigate the changes in serum Myeloid-Related Protein 8/14 (MRP8/14) and Eosinophil Cationic Protein (ECP) levels in patients with different types of coronary artery diseases (CAD) and assess the value of MRP8/14 and ECP detection in predicting CAD. Methods. 178 patients were divided into CAD group including unstable angina pectoris (UAP), acute myocardial infarction (AMI), and stable angina pectoris (SAP). Thirty-six individuals with normal coronary artery served as the control group. Serum MRP8/14 and ECP were measured by ELISA. The severity of coronary artery stenosis was assessed by the numbers of involved coronary artery branches and the sum of Gensini scores. Results. The MRP8/14 levels were significantly higher in AMI and UAP group than SAP and control group (𝑃 < 0.05). The levels of MRP8/14 in AMI group were also obviously higher than UAP group (𝑃 < 0.05). The ECP levels were obviously increased in AMI group, but there was no difference between SAP and UAP group (𝑃 > 0.05). The ECP was significantly increased in three impaired coronary arteries and obviously correlated with Gensini score (𝑃 < 0.01), whereas the MRP8/14 was obviously positively correlated with CRP (𝑃 < 0.01). Conclusions. Increased MRP8/14 levels suggest the instability of the atherosclerotic plaque. ECP reflects the severity of coronary arteries stenosis, predicting atherosclerosis burden. They may become the new biomarkers of CAD. [ABSTRACT FROM AUTHOR]

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Slope approximation method is generally used in numerical simulation of SKM that contains channel cases with vertical wall. However, systemic study on the influences to the precision of SKM method by slope approximation can be hardly found. In order to tackle the issue, sensitivity analysis by using slope approximation method with different approximated angles has been conducted. The result showed that impact on the velocity distribution by the approximated angle is local, but disparity of the velocity distribution in main channel is obvious. It comes to the conclusion that slopping approximation algorithm neither solves the discontinuity at interface with vertical wall nor obtains accurate depth-averaged velocity and shear stress distribution in lateral direction. [ABSTRACT FROM AUTHOR]

A rapid and sensitive method was optimized and validated for the separation and quantification of derivatized monosaccharides in polysaccharide from Potentilla anserine L. using 1-naphthyl-3-methyl-5-pyrazolone (NMP) as precolumn derivatization reagent by capillary zone electrophoresis (CZE). On the basis of the optimum conditions, nine NMP-derivatized monosaccharides achieve baseline resolution within 16 min. The developed method has been successfully applied to analyze component monosaccharides of three Potentilla anserine L. samples, which were obtained by gradational precipitation with 50, 70, and 90% aqueous ethanol, respectively. The polysaccharide precipitated from 50% ethanol solvent was composed of fucose, mannose, xylose, glucuronic acid, glucose, rhamnose, galacturonic acid, galactose, arabinose in molar proportion of 1:1.65:1.99:5.08:7.38:8.14:13.05:27.41:39.02; the corresponding molar proportions for polysaccharide obtained from 70% ethanol solvent were 1:1.64:1.65:4.52:13.96:9.13:26.30:10.52:18.00; fucose and galacturonic acid were not found in the polysaccharide precipitated from 90% ethanol solvent, and mannose, xylose, glucuronic acid, glucose, rhamnose, galactose and arabinose were determined with molar proportion of 1:0.87:1.77:2.78:1.69:2.58:2.49. Quantitative recoveries of the component monosaccharides in the polysaccharide were in the range of 93.3–105.1% and the relative standard deviation (RSD) values fell within 3.4–6.3%, respectively. The results demonstrated that the proposed CZE method was precise and sensitive for the analysis of the composition of polysaccharide. [ABSTRACT FROM AUTHOR]

Abstract: An improved r-factor algorithm for TVD schemes on structured and unstructured grids within a finite volume method framework is proposed for numerical approximation to the convective term. The new algorithm is tested by a problem of pure convection with a double-step profile in an oblique uniform velocity field. The computational results are then compared with the results of Darwish’s r-factor algorithm using Superbee and Osher limiters on both structured and unstructured grids. The numerical results show that the new algorithm can mitigate the oscillation behavior efficiently while still maintaining the boundedness of the solutions. When using a deferred correction technique to handle the non-linear term arising from the high resolution schemes, the proposed algorithm showed a smoother and faster convergence history on structured grids than Darwish’r-factor algorithm, while on unstructured grids the presented one is more accurate with a similar convergence history. [Copyright &y& Elsevier]

Simple Summary: The Asian corn borer (ACB), Ostrinia furnacalis, is an important economic pest of corn and other crops, and is widely distributed in China. Depending on the climate, ACB may have one or up to seven generations each year, from north to south, respectively. The degree of crop damage is closely related to its phenology and number of generations per year (voltinism). Climate warming may result in an alternation of voltinism in the ACB. In the present study, we investigated the voltinism of different populations under different simulated environments. From the diapause response, both the uni- and multivoltine ecotypes were coexisting in the Harbin (H) population collected from action sites of ACB moths in Harbin, Heilongjiang Province, China. Diapause incidence declined given the climate-warming scenario, which was temporally specific and could be overridden by significantly low daily average temperatures. Elevated CO2 did not directly impact voltinism. On the basis of voltinism, the H population reflected sympatric uni- and multivoltine ecotypes, with multivoltinism being dominant. The univoltinism trait was recessive. Climate warming could significantly override photoperiod effects. Warmer temperatures and declining latitude (reduced daylength), and their interaction, are estimated to drive ACB evolution to increased homogeneity and multivoltinism. In the Asian corn borer (ACB), Ostrinia furnacalis (Guenée), diapause is governed by a multigenetic constitution that responds to daylength and temperature with seasonality. The ACB displays uni- or multivoltinism, depending on its geographic specificity. Hence, warmer temperatures may result in alternation of voltinism in the ACB, which will help in understanding the ecological consequences of climate warming on insects. In the present study, we investigated the voltinism in two natural populations from Harbin (H) and Gongzhuling (G) as well as a laboratory (L) population (established from the H population in 2017) of the ACB, at ambient and elevated atmospheric CO2 (aCO2 390 μL/L and eCO2 750 μL/L) and temperature (aT and Et = At + 2 °C). From the diapause response, both the uni- and multivoltine ecotypes were coexisting in the H population. The neonate occurrence date of 50% individuals that induced diapause was ca. 10 days later in the G population than in the H population, but it was about 10 days earlier than in the L population. Comparing to the dates of onset and the peak of diapause induction, the G and L populations were less variable than the H population in response to a short and/or shortening daylength in the field. The univoltine individuals could not be eliminated completely after 19 generations of selection. Diapause incidence decreased with a climate-warming scenario, which was temporally specific and could be overridden by significantly low daily average temperatures. The eCO2 did not directly impact the voltinism. On the basis of voltinism, the H population was sympatric for uni- and multivoltine ecotypes, with multivoltinism being dominant. The univoltinism trait was recessive. Climate warming could significantly override the effect of photoperiod, which was yearly dependent. Warmer temperatures and a decreased latitude (shortened daylength), and their interaction, would drive ACB evolution toward diapause homogeneity for multivoltinism. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effect of aspirin on fractalkine (FKN) in rats with pulmonary embolism (PE). Methods: Sprague Dawley rats were divided into control group, sham operation group, PE model group and PE + aspirin group. PE was established by injecting self-embolus into the right jugular vein of the rats. Aspirin was administered orally 1 day and 40 min before PE surgery, and daily thereafter. At 4 and 72 h following embolism, the rat lung tissues were obtained for hematoxylin-eosin (HE) staining as well as measurement of mRNA expression of FKN, TNF-a and IL-1ß. Additionally, serum FKN, IL-8, TNF-a, and IL-1ß were measured by enzyme linked immunosorbent assay (ELISA). Results: The serum levels of FKN, IL-8, TNF-a and IL-1ß were significantly decreased by treatment with aspirin compared with the PE group (p < 0.05). Furthermore, mRNA expressions of lung FKN, TNF- a and IL-1ß in PE group were markedly decreased by treatment with aspirin compared with that in PE group. PE-induced lung injury was alleviated by treatment with aspirin based on the results of pathological examination. Conclusion: Aspirin has protective effects against PE-induced lung injuries, which is probably mediated by the suppression of the expression of IL-8, TNF-a, IL-1ß, and FKN. [ABSTRACT FROM AUTHOR]

Background: Though the prevalence of diabetes is set to increase, most serious game solutions typically target patient self-management and education. Few games target health care professions education, and even fewer consider the factors that may increase their efficacies. The impact of facilitation, a prominent feature of health professions education, is examined in the context of a rehearsal-based diabetes management serious game., Objective: In this mixed methods, open-label, superiority randomized controlled trial, we compare student performance, attitudes, and perceptions of a rehearsal-based diabetes management game for health care professionals., Methods: Student participants were randomized into 2 groups to play a diabetes management game. The control group played the game alone, and the intervention group played the same game alongside a facilitator tasked to moderate overall challenge levels and address queries. Both groups were administered the Flow Short Scale, a 13-item measure rated on a 7-point Likert scale ranging from 1 ("not at all") to 7 ("very much") immediately after the game. Students were then invited to voluntary focus group discussions to elicit their attitudes and perceptions of the game. Findings were subject to between-group comparisons and inductive thematic analysis respectively., Results: A total of 48 (26 control, 22 intervention) clinical-year undergraduates from the Lee Kong Chian School of Medicine in Singapore participated in this study, with 18 continuing to the focus group discussions. Flow Short Scale results indicated the superiority of the intervention group for overall flow (t 46 =-2.17, P=.04) and the absorption subdomain (t 46 =-2.6, P=.01). Qualitative results indicated students viewed facilitation as helpful and appropriate, and were able to identify improvable elements of the game's theoretical foundations and overall design., Conclusions: While serious games are efficacious means of rehearsing previously learned knowledge, facilitation allows for their efficiency to be greatly increased. Such increases are likely crucial in the coming years with the increased digitization of health care professions education and the prevalence of diabetes., Trial Registration: ClinicalTrials.gov NCT05637749; https://www.clinicaltrials.gov/study/NCT05637749., (©Jun Wen Tan, Gabriel Tan, Xia Lian, Darren Kai Siang Chong, Preman Rajalingam, Rinkoo Dalan, Sreenivasulu Reddy Mogali. Originally published in JMIR Serious Games (https://games.jmir.org), 17.07.2024.)

Background: Obstructive sleep apnea (OSA) syndrome has a negative impact on the health of millions of adolescents and youth. The aim of this study was to evaluate the associations of OSA syndrome with obesity and cardiometabolic risk factors among adolescents and youth at risk for metabolic syndrome (MS)., Methods: A total of 558 subjects aged 14-28 years were recruited from the Beijing Child and Adolescent Metabolic Syndrome Study. Each underwent a 2-h oral glucose tolerance test (OGTT), echocardiography, and liver ultrasonography. Anthropometric measures, blood levels of glucose, lipids, and liver enzymes were assessed. Subjects with high or low risk for OSA were identified by Berlin Questionnaire (BQ)., Results: Among the subjects in obesity, 33.7% of whom were likely to have OSA by BQ. Subjects with high risk for OSA had higher neck and waist circumference and fat mass percentage compared to those with low risk for OSA (P < 0.001). Moreover, significant differences in levels of lipids, glucose after OGTT, and liver enzymes, as well as echocardiographic parameters were found between the two groups with high or low risk for OSA (P < 0.05). The rates of nonalcoholic fatty liver disease (71.0% vs. 24.2%), MS (38.9% vs. 7.0%), and its components in high-risk group were significantly higher than in low-risk group., Conclusions: The prevalence of OSA by BQ was high in obese adolescents and youth. A high risk for OSA indicates a high cardiometabolic risk. Mechanisms mediating the observed associations require further investigation.

Receptor protein tyrosine kinases (RPTKs) play important roles in the regulation of a variety of cellular processes including cell migration, proliferation, and protection from apoptosis. Here, we report the identification and characterization of a novel RPTK-like molecule that has a critical role in induction of tumorigenesis and metastasis and is termed Novel Oncogene with Kinase-domain (NOK). NOK contains a putative single transmembrane domain and a conserved intracellular tyrosine kinase domain that shares homology with members of the platelet-derived growth factor/fibroblast growth factor receptor superfamily. NOK was exclusively located in the cytoplasm. NOK mRNAs were detected in limited human organs and expressed with the highest abundance in the prostate. A variety of tumor cells also expressed the NOK mRNAs. We demonstrated that NIH3T3 and BaF3 cells could be strongly transformed by the expression of the NOK gene as examined by colony formation experiment. In addition, BaF3 cells with the stable expression of NOK induced rapid tumorigenesis in nude mice. Interestingly, these NOK-expressing tumor cells could promptly invade and spread into various distinct organs and form metastatic foci, eventually leading to the rapid death of these animals. Moreover, molecular mechanism studies indicated that NOK could concomitantly activate both MAP kinase and phosphatidylinositol 3'-kinases (PI3K) pathways in stable BaF3 cells. Thus, our results both in vitro and in vivo suggest that NOK is a novel oncogene with the capacity of promoting cell transformation, tumorigenesis, and metastasis.