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This paper aims to study the Galerkin finite element method (FEM) of both the semi-discrete and the fully-discrete schemes with linear triangular element for the time-dependent Joule heating problem. Through some new estimating approaches such as the different mathematical induction assumption, the mean-value technique and the special characters of this element, the superclose and superconvergence estimates for the related variables in the H 1 -norm are derived under lower regularities of the solutions of the considered problem rigorously, which simply the proof process and improve the corresponding results in the existing literature. Finally, numerical results are provided to confirm the theoretical analysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • A ZIF-8 enhanced PVDF/PEO blending polymer gel membrane (PPZ) is designed. • The PPZ with the dense framework exhibits the rapid Na+ migration, superior mechanical property, which is conductive to regulate the Na+ ion flux with the uniform Na plating. • The Na/PPZ-GPE/Na cell delivered the stable cycling for 250 h with almost constant voltage hysteresis of 150 mV. • The SPAN/PPZ-GPE/Na cell exhibited the high capacity of 1585.4 mA h g−1 with the capacity retain of 97 % of third cycle after 465 cycles. Ambient-temperature sodium-sulfur (Na-S) battery with high energy density and low cost has been considered as the promising energy density system. However, its commercial application is limited by the rapid capacity decay of the sulfur electrode and the instability of sodium dendrites with the safety issues. Herein, a ZIF-8 enhanced PVDF/PEO blending polymer gel membrane (PPZ) is reported for stable and safe quasi-solid-state Na-S battery with sulfurized polyacrylonitrile (SPAN) cathode and Na metal anode. The optimized gel polymer membrane with the dense framework exhibited the rapid Na+ migration, superior mechanical property with the tensile strength of 16.5 MPa and the elongation-at-break of 171 %, which is conductive to regulate the Na+ ion flux with the uniform Na plating and prevent the dendritic growth. The assembled symmetric Na/PPZ-GPE/Na cell delivered the stable cycling for 250 h with almost constant voltage hysteresis of 150 mV. Benefited from the superior interfacial stability between PPZ-GPE and Na as well as PPZ-GPE and SPAN, the SPAN/PPZ-GPE/Na cell exhibited the high capacity of 1585.4 mA h g−1 with the capacity retain of 97 % of third cycle after 465 cycles. This work offers exemplary electrolyte design that concurrently and effectively tackles the problems in Na-S battery and presents an excellent quasi-solid sodium-sulfur battery with the high capacity and long cycling. [ABSTRACT FROM AUTHOR]

In this paper, the discontinuous Galerkin method (DGM) of nonconforming Wilson element is studied for the semi-linear parabolic problem. The global superconvergence with respect to the mesh size are derived in the modified H 1 -norm for the semi-discrete scheme and two fully discrete schemes, in which the usual extrapolation and interpolation post-processing approaches are not involved, and the error estimates are one order higher than that of the traditional Galerkin finite element method (FEM). Therefore, the corresponding results in the existing literature are improved. Finally, some numerical results are provided to confirm the theoretical analysis. [ABSTRACT FROM AUTHOR]

Aims: Chondrosarcoma (CS) is a high-morbidity, relatively common bone malignancy without well-established biomarkers. The proteins EAAT1, DHFR, and fetuin-A have been investigated in many cancers, but their specific relationship to CS has not been reported. The present study examined EAAT1, DHFR, and fetuin-A expression in CS and the clinicopathological significance of these proteins in CS pathogenesis, progression, and prognosis. Methods: EAAT1, DHFR, and fetuin-A protein levels in 80 CS and 25 chondroma specimens were measured by immunohistochemistry and related to histological and clinical factors with chi-squared tests. Following univariate survival analysis, ROC curves calculation, and multivariate analysis. Results: EAAT1, DHFR, and fetuin-A expression levels were significantly higher in the CS group than in the chondroma group (p < 0.05). Their immunopositivity rates were significantly greater in tissues with moderate or poor tumor differentiation, AJCC stage III or IV, Enneking stage II or III, and metastasis (p<0.05 or p<0.01 or p<0.001). Kaplan–Meier survival analysis showed significantly shorter survival in patients with moderately or poorly differentiated tumors, AJCC stage III or IV CS, Enneking stage II or III CS, metastasis, invasion, or EAAT1, DHFR, and fetuin-A immunopositivity (p < 0.05 or p < 0.001). Cox regression analysis showed that moderate or poor tumor differentiation, AJCC stage III or IV, Enneking stage II or III, metastasis, invasion, and EAAT1, DHFR, or fetuin-A immunopositivity correlated negatively with postoperative survival and positively with mortality (p < 0.05). The AUCs for EAAT1, DHFR, and fetuin-A were 0.654 (95% CI: 0.532–0.776, p = 0.025), 0.638 (95% CI: 0.519–0.756, p = 0.039), and 0.670 (95% CI: 0.556–0.784, p = 0.011), respectively. Conclusion: EAAT1, DHFR, and fetuin-A may be important biomarkers of the pathogenesis and progression of CS and predictors of its prognosis. [ABSTRACT FROM AUTHOR]

Abstract An H 1 -Galerkin mixed finite element method (MFEM) is developed for the Benjamin–Bona–Mahony (BBM) equation with the bilinear element and zero order Raviart–Thomas element pair (Q 11 ∕ Q 10 × Q 01). Then based on the special interpolation properties of the above two elements and the mean-value technique, the supercloseness and superconvergence results of order O (h 2) for the semi-discrete scheme and of order O (h 2 + (Δ t) 2) for the Crank–Nicolson fully-discrete scheme are deduced for the original variable u in H 1 -norm and the flux p → in H (d i v , Ω) -norm, respectively. Finally, a numerical example is carried out to demonstrate the theoretical analysis. [ABSTRACT FROM AUTHOR]

A Galerkin finite element method (FEM) is developed for nonlinear Poisson–Nernst–Planck (PNP) equations. Based on the combination technique of the element's interpolation and Ritz projection together with the special mean value approach, the superclose and superconvergence estimates with order O (h 2) are derived under weaker regularity requirements of the exact solution. Some numerical results are provided to confirm the theoretical analysis. [ABSTRACT FROM AUTHOR]

Background Long-term care residents were among the most vulnerable during the COVID-19 pandemic. We estimated vaccine effectiveness of mRNA COVID-19 vaccines in Medicare nursing home residents aged ≥65 years during pre-Delta and high Delta periods. Methods We conducted a retrospective cohort study from 13 December 2020 to 20 November 2021 using Medicare claims data. Exposures included 2 and 3 doses of Pfizer-BioNTech and Moderna COVID-19 vaccines. We used inverse probability weighting and Cox proportional hazards models to estimate absolute and relative vaccine effectiveness. Results Two-dose vaccine effectiveness against COVID-19–related death was 69.8% (95% CI, 65.9%‒73.3%) during the pre-Delta period and 55.7% (49.5%‒61.1%) during the high Delta period, without adjusting for time since vaccination. We observed substantial waning of effectiveness from 65.1% (54.2%‒73.5%) within 6 months from second-dose vaccination to 45.2% (30.6%‒56.7%) ≥6 months after second-dose vaccination in the high Delta period. Three doses provided 88.7% (73.5%‒95.2%) vaccine effectiveness against death, and the incremental benefit of 3 vs 2 doses was 74.6% (40.4%‒89.2%) during high Delta. Among beneficiaries with a prior COVID-19 infection, 3-dose vaccine effectiveness for preventing death was 78.6% (50.0%‒90.8%), and the additional protection of 3 vs 2 doses was 70.0% (30.1%‒87.1%) during high Delta. Vaccine effectiveness estimates against less severe outcomes (eg, infection) were lower. Conclusions This nationwide real-world study demonstrated that mRNA COVID-19 vaccines provided substantial protection against COVID-19–related death. Two-dose protection waned after 6 months. Third doses during the high Delta period provided significant additional protection for individuals with or without a prior COVID-19 infection. [ABSTRACT FROM AUTHOR]

The number, size, and composition of lipid droplets can be influenced by dietary changes that shift energy substrate availability. This diversification of lipid droplets can promote metabolic flexibility and shape cellular stress responses in unique tissues with distinctive metabolic roles. Using Drosophila, we uncovered a role for myocyte enhancer factor 2 (MEF2) in modulating diet‐dependent lipid droplet diversification within adult striated muscle, impacting mortality rates. Muscle‐specific attenuation of MEF2, whose chronic activation maintains glucose and mitochondrial homeostasis, leads to the accumulation of large, cholesterol ester‐enriched intramuscular lipid droplets in response to high calorie, carbohydrate‐sufficient diets. The diet‐dependent accumulation of these lipid droplets also correlates with both enhanced stress protection in muscle and increases in organismal lifespan. Furthermore, MEF2 attenuation releases an antagonistic regulation of cell cycle gene expression programs, and up‐regulation of Cyclin E is required for diet‐ and MEF2‐dependent diversification of intramuscular lipid droplets. The integration of MEF2‐regulated gene expression networks with dietary responses thus plays a critical role in shaping muscle metabolism and function, further influencing organismal lifespan. Together, these results highlight a potential protective role for intramuscular lipid droplets during dietary adaptation. [ABSTRACT FROM AUTHOR]

Background: HMGB1 and ER stress have been considered to participate in the progression of pulmonary artery hypertension (PAH). However, the molecular mechanism underlying HMGB1 and ER stress in PAH remains unclear. This study aims to explore whether HMGB1 induces pulmonary artery smooth muscle cells (PASMCs) functions and pulmonary artery remodeling through ER stress activation. Methods: Primary cultured PASMCs and monocrotaline (MCT)-induced PAH rats were applied in this study. Cell proliferation and migration were determined by CCK-8, EdU and transwell assay. Western blotting was conducted to detect the protein levels of protein kinase RNA-like endoplasmic reticulum kinase (PERK), activating transcription factor-4 (ATF4), seven in absentia homolog 2 (SIAH2) and homeodomain interacting protein kinase 2 (HIPK2). Hemodynamic measurements, immunohistochemistry staining, hematoxylin and eosin staining were used to evaluate the development of PAH. The ultrastructure of ER was observed by transmission electron microscopy. Results: In primary cultured PASMCs, HMGB1 reduced HIPK2 expression through upregulation of ER stress-related proteins (PERK and ATF4) and subsequently increased SIAH2 expression, which ultimately led to PASMC proliferation and migration. In MCT-induced PAH rats, interfering with HMGB1 by glycyrrhizin, suppression of ER stress by 4-phenylbutyric acid or targeting SIAH2 by vitamin K3 attenuated the development of PAH. Additionally, tetramethylpyrazine (TMP), as a component of traditional Chinese herbal medicine, reversed hemodynamic deterioration and vascular remodeling by targeting PERK/ATF4/SIAH2/HIPK2 axis. Conclusions: The present study provides a novel insight to understand the pathogenesis of PAH and suggests that targeting HMGB1/PERK/ATF4/SIAH2/HIPK2 cascade might have potential therapeutic value for the prevention and treatment of PAH. [ABSTRACT FROM AUTHOR]

Purpose. To evaluate the rate of presumed endophthalmitis (EO) after intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections performed in an operating room (OR) under sterile conditions in mainland China. Methods. Retrospective single-center study between September 2012 and December 2017 at Beijing Tongren Eye Center, Beijing, China. Intravitreal injection database was reviewed. All anti-VEGF injections were performed using a standardized sterile technique in an OR. Injection protocols included antibiotics for 3 days pre-injection, topical 5% povidone-iodine rinsing before the procedure, and post-injection antibiotics for 3 days. Results. A total of 37,830 intravitreal injections were performed at Beijing Tongren Eye Center. Three cases were managed as presumed EO (0.0079%). Positive cultures were documented in 2 of 3 cases. EO incidence following ranibizumab and conbercept administration was 0.0088% (3 in 33,930) and 0% (0 in 3,900), respectively. No significant difference was detected between the two drugs (P = 0.745). Conclusions. Very low EO rates were seen in mainland China using a standardized sterile technique in an OR. However, EO could not be completely avoided. [ABSTRACT FROM AUTHOR]

SnS 2 nanosheet (NS), SnS 2 nanoflower (NF) and SnS 2 NF@reduced graphene oxide (rGO) were synthesized by hydrothermal method. When used as anode materials for lithium-ion batteries (LIBs), SnS 2 NF@rGO exhibits reversible specific capacities of 525 mAh/g at 0.5C after 360 cycles and 412.5 mAh/g at 2.0C, which are significantly enhanced Li storage performance over SnS 2 NS and SnS 2 NF. The detailed electrochemical impedance spectroscopy (EIS) analysis were found that SnS 2 NF@rGO nanocomposite exhibits much reduced internal resistance originated from the decreasing Warburg factor. The electronic conductivity of the cycled SnS 2 NF@rGO is about three times more than that of cycled SnS 2 NS and SnS 2 NF. More importantly, the Li+ diffusion coefficients D L i + were calculated using the galvanostatic intermittent titration technique (GITT) method, indicating SnS 2 NF@rGO demonstrated much enhanced Li+ diffusion kinetics than that of electrodes without rGO additives. This means that SnS 2 NF@rGO is more suitable to be applied as anode materials for LIBs because the electrochemical performance was enhanced by the improved ionic transport properties, resulting from the increased electronic conductivity by the addition of two-dimensional layer structure rGO with superior electronic conductivity. This study could help us understanding how electronic conductivity contributed to ionic transport kinetics in electrochemical energy storage and conversion (EESC). • SnS 2 NF@rGO nanocomposite was synthesized by hydrothermal method. • SnS 2 NF@rGO exhibits reduced internal resistance leads to improved electrochemical performance. • The rGO additives leads to improved Li+ diffusion kinetics of SnS 2 NF@rGO. [ABSTRACT FROM AUTHOR]

• RNA interference (RNAi) is of great value in plant functional genomics. However, the absence of RNAi phenotypes and the lack of uniform level of RNAi silencing has complicated gene identification. Here, the penetrance and expressivity of RNAi-mediated silencing of the phytoene desaturase ( PDS) gene in Arabidopsis thaliana were examined quantitatively to provide a reference for the likely severity and distribution of silencing effects. • Arabidopsis plants were transformed with an RNAi construct targeting PDS. Transgenic plants were examined for frequency of RNAi-mediated silencing and various silencing phenotypes. mRNA depletion level and RNAi expressivity were assayed by relative reverse transcription polymerase chain reaction (RT-PCR). • High penetrance and variable expressivity of RNAi were demonstrated. An inverse correlation between PDS mRNA level and RNAi phenotype was seen. No direct relationship between copy number for the RNAi-generating transgene and phenotype was evident. Decreased RNAi penetrance in T2 plants was observed. • It is suggested that variability in RNAi expressivity and postmeiotic decrease in RNAi penetrance constitute barriers for high throughput plant gene characterization. New Phytologist (2005) doi: 10.1111/j.1469-8137.2005.01454.x © New Phytologist (2005) [ABSTRACT FROM AUTHOR]

C-doped Fe 2 MnGaC x (x = 0, 0.05, 0.1 and 0.2) alloys have been synthesized and the influence of carbon on the structure and magnetic properties of Fe 2 MnGa has been investigated. The doping of C can expand the lattice of Fe 2 MnGa, suggesting that it enters the interstitial site of FCC lattice. The ferromagnetic coupling in Fe 2 MnGaC x can be strongly enhanced with increasing C content. The ferromagnetic to antiferromagnetic transition in undoped Fe 2 MnGa is suppressed by C-doping and disappears when x = 0.1 and 0.2. The saturation magnetization M s and Curie temperature T C also increase with C-doping. Large coercivity and exchange bias can be observed in the magnetic hysteresis loops of Fe 2 MnGa, due to the coexistence of FM and AFM states. But in Fe 2 MnGaC 0.2 , both of them disappear and a pure ferromagnetic character is observed. All this suggests that C-doping can be a possible way to adjust the magnetic properties of Fe 2 MnGa and other related alloys. • Fe 2 MnGaC x alloys were synthesized successfully. • Effect of C-doping on structure and magnetism of Fe 2 MnGa was studied. • Ferromagnetic state in Fe 2 MnGa can be strongly enhanced by C-doping. • A possible way to adjust the magnetic structure of Fe 2 MnGa is proposed. [ABSTRACT FROM AUTHOR]