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Lead-free dielectric energy storage ceramics have attracted much attention in the fields of medicine, electronic components and military because of their ultra-high efficiency and high energy storage density. In this study, (1-x)(Bi0.5Na0.5)0.7Ba0.3TiO3-xLiTa0.97Nb0.03O3 (BNBT-xLTN) lead-free relaxation energy storage ceramics have been prepared by solid-phase high-temperature sintering.XRD analysis confirms that all the components of BNBT-xLTN ceramics are in a single-phase chalcocite structure, and no heterogeneous phases are detected. With the increase of LTN doping, the relaxation and energy storage properties of the ceramics were significantly improved, while the microscopic morphology showed a dense state with uniform particle size and no pores, which improved the breakdown strength (Eb) of the ceramics. Analysis of the experimental results 0p showed that the LTN-doped ceramics displayed finer electric hysteresis return lines (P-E) as compared to the undoped BNBT (x = 0).The electrical performance of the ceramics is significantly enhanced at 30 kV/mm field strength when LTN doping x = 0.10. Its recoverable energy storage density is as high as Wrec = 4.95 J/cm3 and η = 93.2% with ultra-high energy storage efficiency. The ceramic also has an ultra-short discharge time of t0.9 = 0.38 μs. This study demonstrates the great potential of this ceramic system for practical applications. [ABSTRACT FROM AUTHOR]

While the macronutrient calcium (Ca) has been utilized to mitigate fluorine (F) toxicity in soils for plants, its role in alleviating phytotoxicity from atmospheric F exposure remains underexplored. This study investigates the effect of foliar-applied Ca on the growth, physio-biochemical characteristics, and F accumulation in Chinese cabbage (Brassica chinensis L.) following both foliar and root F exposure. Results show that foliar application of Ca (0.5 and 1.0 g L−1) significantly enhanced the root length, plant height, and biomass of plants exposed to foliar F at 20 mg L−1, in comparison to the control group, with no notable improvement observed in plants subjected to root F exposure. Foliar application of Ca at 0.5 g L−1 increased chlorophyll production, alleviated the oxidative impairment in leaves, and mediated protective responses specifically under atmospheric F stress, as evidenced by increased chlorophyll concentration and reduced MDA and proline levels. In seedlings with foliar F exposure, F concentration in leaves decreased by 19.9% following foliar application of 1.0 g L−1 Ca compared to the control group without Ca. Additionally, foliar application of Ca at 1.0 g L−1 showed potential in mitigating the health risks associated with consumption of the leafy vegetable grown in F-enriched atmospheres. These findings suggest that foliar Ca application is a promising strategy for mitigating the adverse effects of atmospheric F on leafy vegetables. [ABSTRACT FROM AUTHOR]

This study adopts a new approach to reassess the factors influencing urban energy intensity in China. Initially, the factors impacting energy intensity are classified into controllable and uncontrollable categories. Subsequently, employing a single-factor multi-stage method combined with the Adaboost method, 289 Chinese cities are categorized based on uncontrollable factors to eliminate the influence of inherent differences on energy intensity. Finally, panel data regression analyses are conducted using data from 289 Chinese cities between 2005 and 2016, individually for each city type, to evaluate the extent to which controllable factors contribute to energy intensity. The findings indicate that (1) heightened energy prices, an increased share of electricity consumption, and a greater proportion of centralized heating significantly influence the reduction of energy intensity across all city types; (2) to optimize energy consumption, each city type should adopt specific strategies. For instance, cities located in resource-rich heating regions with low economic outputs can reduce their energy intensity by increasing electricity consumption, while cities with high economic outputs can decrease their energy intensity by increasing natural gas consumption. The findings of this study carry substantial implications for the Chinese government in shaping targeted energy policies tailored to different city types. [ABSTRACT FROM AUTHOR]

Currently, in the modification methods of K0.5Na0.5NbO3(KNN) ceramics to enhance their piezoelectric performance, key parameters such as Curie temperature are usually sacrificed. However, this trade-off limits the practical application of piezoelectric materials. Thus, addressing the trade-off between different performance parameters of piezoelectric ceramics becomes a major challenge.The present research employs the conventional solid phase sintering process and utilizes controlled doping of (Bi0.5Li0.5)0.9Sr0.1ZrO3 to regulate the ceramic system, K0.44Na0.55Ag0.01Nb0.95Ta0.05O3, at its polycrystalline phase boundary, thereby achieving a trade-off between performance. The ceramic samples of the system formed a compact solid solution with a single-phase perovskite structure and formed orthorhombic-tetragonal and rhombohedral-tetragonal polycrystalline phase boundaries at 0.02 ≤ x ≤ 0.03 and 0.035 ≤ x ≤ 0.06, respectively, according to XRD, SEM, and EDS analysis. The electrical properties test results show that in the multiphase coexisting region of x = 0.035, the ceramics of the system show excellent electrical properties, respectively d33 = 312 pC/N, kp = 46.5%, εr = 1019, tanδ = 3.78%, Pr = 20.08 μC/cm2, Ec = 12.97 kV/cm, and TC = 342 ℃. These results show that the properties of the system ceramics have reached a relatively high level, which provides an effective strategy for the practical application of piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the context of inhomogeneous laser fields, laser field intensity plays a pivotal and indispensable role in shaping the photoelectron momentum distributions (PMDs). This theoretical exploration delves into the intricate relationship between laser field intensity and PMDs. As laser field intensity increases, a discernible transformation unfolds within the PMDs, leading to the emergence of distinctive regions. Remarkably, this increase in laser field intensity obfuscates the once-prominent holographic interference phenomena, rendering them imperceptible. The theoretical framework reveals that electron tunneling, particularly in proximity to the peak of the laser pulse within the inhomogeneous field, stands as the primary driver behind the formation of high-energy structures. Similarly, our inquiry extends to scrutinizing the influence of the inhomogeneous coefficient on these high-energy structures. We further embark on a comprehensive analysis of the initial momentum inherent in the electron wave packet. It becomes evident that PMDs exhibit a keen sensitivity to the initial momentum, thereby revealing yet another layer of complexity in this multifaceted phenomenon. As an intriguing revelation, we unveil the potential for attaining high-energy structures at comparatively lower laser field intensities through strategic modulation of the inhomogeneity coefficient. This nuanced interplay between laser field intensity, inhomogeneity coefficient, and initial momentum provides a comprehensive understanding of the intricate dynamics underpinning the photoelectron momentum distribution in inhomogeneous laser fields. [ABSTRACT FROM AUTHOR]

The effect of renal functional status on drug metabolism is a crucial consideration for clinicians when determining the appropriate dosage of medications to administer. In critically ill patients, there is often a significant increase in renal function, which leads to enhanced drug metabolism and potentially inadequate drug exposure. This phenomenon, known as augmented renal clearance (ARC), is commonly observed in pediatric critical care settings. The findings of the current study underscore the significant impact of ARC on the pharmacokinetics and pharmacodynamics of antimicrobial drugs in critically ill pediatric patients. Moreover, the study reveals a negative correlation between increased creatinine clearance and blood concentrations of antimicrobial drugs. The article provides a comprehensive review of ARC screening in pediatric patients, including its definition, risk factors, and clinical outcomes. Furthermore, it summarizes the dosages and dosing regimens of commonly used antibacterial and antiviral drugs for pediatric patients with ARC, and recommendations are made for dose and infusion considerations and the role of therapeutic drug monitoring. Conclusion: ARC impacts antimicrobial drugs in pediatric patients. What is Known: • ARC is inextricably linked to the failure of antimicrobial therapy, recurrence of infection, and subtherapeutic concentrations of drugs. What is New: • This study provides an updated overview of the influence of ARC on medication use and clinical outcomes in pediatric patients. • In this context, there are several recommendations for using antibiotics in pediatric patients with ARC: 1) increase the dose administered; 2) prolonged or continuous infusion administration; 3) use of TDM; and 4) use alternative drugs that do not undergo renal elimination. [ABSTRACT FROM AUTHOR]

In this experiment, a new lead-free energy storage ceramic (1-x)(Na0.5Bi0.5)0.935Sr0.065TiO3–xNa0.7Bi0.08La0.02NbO3 was prepared using a conventional solid-phase sintering process, and the influence of doping with Na0.7Bi0.08La0.02NbO3 on the relaxation and storage properties of this ceramic was systematically investigated. After multi-scale testing, the results demonstrate that the ceramic system forms a perovskite-structured solid solution with a dense single phase. The ceramic samples exhibit a homogeneous microstructure with smaller grain sizes as doping increases, which enhances the breakdown field strength (30 kV/mm), as detected by SEM. The ceramic in this system demonstrates good electrical qualities, with a recoverable energy storage density of Wrec = 7.44 J/cm3 and energy storage efficiency of η = 87.70% at a field strength of 30 kV/mm at x = 0.20, according to the findings of the electrical properties test. It also also exhibits good stability over a wide frequency range (5–100 Hz): Wrec = 7.2 ± 3% J/cm3, η = 86.1 ± 3.2%, and over a wide temperature range (30–170 °C): Wrec = 7.1 ± 5% J/cm3, η = 83.1 ± 4.3%. Additionally, it has a fast discharge rate of t0.9 = 0.35 µs. This excellent electrical property predicts that this system of ceramics has great application prospects in the field of energy storage capacitors in the future. [ABSTRACT FROM AUTHOR]

Phytochemical investigation of 70% EtOH extract of the seeds of Capsella bursa-pastoris led to the isolation of a new cyclobutane organic acid (1), and fourteen known compounds, including two organosulfur compounds (2, 3), two quinonoids (4, 5), five flavonoids (6-10), three sterols (11-13) and two other types (14, 15). The structures of the compounds were elucidated by extensive spectroscopic analyses as well as comparison of their spectroscopic data with those reported in the literature. The antioxidant capacities of all compounds and extractive fractions were evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging test and ferric reducing antioxidant power (FRAP) assay. Then the antioxidative substances were evaluated for their neuroprotective effects against H2O2-induced HT22 cell injury. The results indicated the strong scavenging ability to free radical of the extractive fractions and compounds 1-3, 8-10 and 13, and the ferric reducing antioxidant power of the extractive fractions and compounds 1-3, 8 and 10, which were close to or higher than that of the positive control trolox. The EtOAc fraction, n-BuOH fraction, and compounds 1, 3 and 8 can protect HT-22 cells from oxidative damage. [ABSTRACT FROM AUTHOR]

Fluorine (F) is not an essential element for vegetation and excessive F can be phytotoxic to plant growth, which can cause fluorosis to human beings by ingesting F-contaminated plant. Although there have been some studies focusing on the toxicity of F to plants and the retarding effect of Ca to F-stress plant, atmospheric F contamination to vegetation and the role of the application of foliar Ca are scantly reported. This study investigated several biochemical parameters to evaluate F toxicity under both F-exposure (root and leaf F-exposure) and the remedial effects of foliar Ca. The results showed that F concentration of pakchoi leaves was correlated with exogenous F level positively in both foliar and root F-exposure series, and F concentration of pakchoi roots was only changed under root F-exposure treatments. Ca supplement (0.5 g/L and 1 g/L) significantly decreased plant F concentration. Both F-exposure treatments caused lipid peroxidation in plants and exogenous Ca alleviated the toxicity of F to pakchoi. Meanwhile, chlorophyll-a concentration was decreased by foliar and root F, whereas chlorophyll-b concentration was only affected by foliar F, and chlorophyll-a concentration could be elevated by exogenous Ca but chlorophyll-b could not. It was concluded that both atmospheric and root F can impair pakchoi growth and disturb photosynthesis, and foliar Ca showed an ameliorative effect to F toxicity of pakchoi through alleviating chlorophyll decomposition, increasing protein content and alleviating oxidative damage. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) micro/nanofiber fabrics with good biodegradability and biocompatibility have wide applications in the medical protective field. However, the poor flexibility, high brittleness, and insufficient mechanical properties of PLA micro/nanofiber fabrics remain challenging. Herein, a polylactic acid/polyethylene glycol (PLA/PEG) micro/nanofiber fabric with aligned fibers was successfully prepared by an inexpensive and straightforward post-drafting melt blown process. The experimental results showed that PEG can reduce the Tg of PLA, improve the mobility of PLA molecular chains, reduce the complex viscosity of PLA/PEG blends, and play a role in plasticization. The PLA/PEG micro/nanofiber fabrics had an aligned micro/nanofibrous structure, and the average fiber diameter was easily adjusted from 10.7 to 4.9 μm by tailoring the melt blown process parameters, i.e., die temperature and hot air temperature. Moreover, the breaking tensile strength increased from 45.06 to 78.73 N in the machine direction (MD), while it increased from 11.87 to 21.89 N in the cross direction (CD), which means that the breaking tensile strength was enhanced significantly by adjusting the die temperature and hot air temperature. Furthermore, the prepared samples showed a high softness score of 82.7, a large synthetic blood contact angle of 125.7°, and an excellent bursting strength of 58.5 N. These PLA/PEG micro/nanofiber fabrics with aligned fibers are ideal candidates for medical protective applications such as surgical gowns, protection suits, masks, and medical bandages. [ABSTRACT FROM AUTHOR]

Purpose: To assess how expansion sphincter pharyngoplasty (ESP) impacts blood pressure (BP) and health-related quality of life (HRQOL) in hypertensive patients with obstructive sleep apnea (OSA). Methods: Patients were separated into two groups based upon whether or not they adhered to antihypertensive drug regimens. Patients underwent 24-h ambulatory BP monitoring before and at 6 months post-ESP, while clinical BP measurements and HRQOL questionnaires (SF-36) were conducted over the course of 24 months post-surgery. Results: We enrolled 62 patients, with 25 and 37 in the medicated and non-medicated groups, respectively. Mean 24-h BP differed significantly, with systolic and diastolic BP (SBP and DBP) decreases of 5.3 mmHg and 2.5 mmHg, respectively (P <0.01). Mean 24-h SBP and DBP decreases in the medicated group were 10.2 mmHg and 4.6 mmHg, respectively (P < 0.001), with significant decreases during the daytime of 8.6 mmHg, 3.0 mmHg, and nighttime of 12.3 mmHg, 7.7 mmHg (P <0.001). In the non-medicated treatment group, 24-h SBP and DBP decreases were 1.9 mmHg and 1.1 mmHg (P < 0.005) with significant decreases in mean nighttime BP values of 3.2 mmHg and 1.9 mmHg (P < 0.001). While pre- and postoperative SF-36 results differed significantly, no differences were observed between the two groups. Conclusion: ESP decreases BP and improves HRQOL in OSA patients with hypertension, particularly in combination with antihypertensive drugs. [ABSTRACT FROM AUTHOR]

Purpose: Although hypolimnetic anoxia is a common occurrence in deep lakes and reservoirs, understanding the processes of oxygen depletion in water columns and sediment is challenging. This study investigates oxygen depletion in both the hypolimnion and sediments in a stratified reservoir. The areal hypolimnetic oxygen demand (AHOD) and sediment oxygen demand (SOD) were evaluated to determine key factors of hypolimnetic anoxia. Materials and methods: To evaluate the characteristics of the AHOD in the Jinpen Reservoir (JPR), China, 4 years of field observations of dissolved oxygen (DO) and temperature datasets in the water column are analyzed. SOD was calculated as the sum of the sediment oxygen uptake ( J O 2 ) and the flux of reduced substances from deeper sediment layers into the overlying water (Fred), where J O 2 was obtained from DO profiles across the sediment–water interface (SWI) at a depth of approximately 94 m in the reservoir, and Fred was obtained from sediment cores. Results: The AHOD in the JPR varied from 0.299 to 1.451 g m−2 day−1 during the summer stratification between 2014 and 2017. The SOD, containing J O 2 and Fred, decreased from 0.534 to 0.386 g m−2 day−1 during stratification. Within the SOD, J O 2 decreased from 0.415 to 0.168 g m−2 day−1, whereas Fred increased from 0.119 to 0.218 g m−2 day−1. Conclusion: The increase in primary productivity (e.g., diatom blooms), inflows during rainfall, and oxygen concentrations can significantly increase AHOD. The relative importance of J O 2 at 40–70% of the SOD is high in the JPR; thus, oxic respiration of organic carbon is the dominant pathway of DO consumption. [ABSTRACT FROM AUTHOR]

Fluorine (F) is widely distributed in soils and is not an essential element for the normal growth of a plant, but in higher concentrations, it is toxic. However, the environmental toxicity of F in soils is still controversial. A pot experiment of broad bean and maize under the exposure to F was performed to elucidate F phytotoxicity and the response of the microbial community in soils. Six different levels (0, 200, 400, 600, 800, and 1000 mg kg–1) of sodium fluoride were spiked into the soil. The results revealed that the height of stem and root decreased with increasing concentration of F. Germination rate and fresh weight showed no difference in different treatments. At the treatment of 1000 mg kg−1 F, the degradation rates of pigments were 30.6%, 42.9%, and 35.7% for chlorophyll a, chlorophyll b, and total chlorophylls compared with control, respectively. All treatments showed a higher level of F accumulation in root than that in stem and leaf, and stem had a minimum F accumulation. Proteobacteria was the dominant species in bacteria and the relative abundance of Proteobacteria declined significantly with F exposure. Moreover, the number of microbial species both in bacteria and fungus was reduced for the increase of F. In general, our results revealed that high concentrations of F inhibited the growth of broad bean and maize but without visual symptom. The effect of fluorine on broad bean and maize is clarified in the present study which is instructive for agricultural safety. [ABSTRACT FROM AUTHOR]

Growth shapes soft tissues not only through mass addition or volume expansion but also through deformation instabilities and consequent morphological evolution. In this paper, we probe the torsion instability of an anisotropically growing tube with fiber reinforcement, which mimics many tubular organs in animals or plants. We derive the Stroh formulation for the incremental boundary value problem and numerically solve it using the surface impedance method. A linear stability analysis is conducted to investigate the critical condition for the onset of wrinkling. The thresholds of helical wrinkling are calculated in terms of growth ratio and external load. The effect of fibers on the critical state under axial stretching is examined. It is found that the tangential growth tends to enhance the critical torsion angle but has a weak influence on the critical longitudinal mode of wrinkling, which, however, can be remarkably affected by the axial growth. Our study can help understand the formation of helical morphologies in biological materials and provide cues for engineering desired structures or devices. [ABSTRACT FROM AUTHOR]

Smart hydrogels have received increasing attention for their great potential for the applications in many fields. Herein, we report a facile approach to prepare a class of dual-responsive hydrogels assembled from synthetic statistical/block thermal-responsive copoly(L-glutamate)s copolymerized with poly(ethylene glycol), which were prepared by ring-opening polymerization (ROP) and post-modification strategy. The incorporation of oligo(ethylene glycol) (OEG) and glutamic acid residues offers the gels with thermal- and pH-responsive properties simultaneously. We have systematically studied the influence of both temperature and pH on the gelation behaviors of these copolymers. It is found that the increase of glutamic acid content and solution pH values can significantly suppress the gelation ability of the samples. Circular dichroism (CD) results show that the α-helix conformation appears to be the dominant secondary conformation. More interestingly, the gelation property of the block copolymer with statistical thermal-responsive copoly(L-glutamate)s shows greater dependence on pH as compared to that with block segments due to the distinct morphology of the self-assemblies. The obtained hydrogels exhibit pH-dependent and thermal-responsive gelation behaviors, which enable them as an ideal smart hydrogel system for biomedical applications. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science B is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Polycystic ovary syndrome (PCOS) is a prevalent endocrinological disorder in reproductive-age women and is often associated with a metabolic syndrome. To investigate whether exercise intervention promotes PCOS prevention, a rat model was used. Polycystic ovary syndrome was induced by letrozole administration, and animals presented with obesity, sex hormone disorder, no ovulation, large cystic follicles, and increasing fasting insulin (FINS) and leptin levels. The intervention was set at 3 different intensities of swimming exercise: low (0.5 h/d), moderate (1 h/d), and high (2 h/d), and compared with a PCOS model group (letrozole administration without exercise intervention) and a control group. The exercise intervention in the low-intensity group did not produce changes in obesity, testosterone, progesterone (P), and follicle-stimulating hormone (FSH) levels. Moderate-intensity exercise reduced body weight, retained ovulation, and P levels were increased but remained lower than those in the control group. The FSH levels were significantly higher, and FINS and leptin levels were lower than in the model group (P < 0.05) but not in the control group. The high-intensity group demonstrated the greatest effect of PCOS prevention. Testosterone, luteinizing hormone, FINS, and leptin levels were significantly lower in the high-intensity group, and FSH and P levels were higher compared with the model group. These results suggest that high-intensity exercise intervention can effectively prevent PCOS development. [ABSTRACT FROM AUTHOR]

The fabric used for intimate apparel is widely required to have excellent antibacterial and comfort performances. In order to improve its antibacterial ability, this paper studied chitosan-silver finishing on the cotton knitted fabric. The study indicates that the chitosan-silver attached to the fabric exhibits excellent antibacterial action against the typical bacteria of Escherichia coli ( E. coli) and Staphylococcus aureus ( S. aureu). The anti-bacterial mechanism of chitosan-silver against E. coli and S. aureu were investigated. To guarantee its prominent comfort performance, measurements were made on the finished fabric of its air permeability, water vapor transmission, hydrophily, surface friction and bending ability against the control fabric, which is currently used for intimate apparel. The antibacterial and comfort performances were compared between the tested fabrics. The results show that the air permeability and the hydrophily of the finished cotton fabric are significantly better than the control one, while the water vapor transmission, the surface friction and the adjustable rate remain similar to each other. The bending rigidity of the finished fabric is slightly better due to the attachment of chitosan within accepted threshold. The dual compounding theory of chitosan-silver proves to be useful for a higher synergistic effect of anti-bacteria, lower whiteness degradation and overall optimization of comfort performance. This dual compounding theory of chitosan-silver is valuable for improving antibacterial and comfort performances of intimate apparel. [ABSTRACT FROM AUTHOR]