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Ceria-doped tetragonal zirconia polycrystal (Ce-TZP) ceramics possess significant toughness and aging resistance, while their strength is relatively limited due to the high tendency of grain growth, which has long hindered their versatile applications. This work demonstrates an effective method to combine stereolithography with pre-sintering and hot isostatic pressing (HIP) to obtain dense Ce-TZP ceramics with a reduced grain size of about 420 nm. In addition to the contribution of smaller grains, the Ce-rich phase Ce 0.75 Zr 0.25 O 2 precipitates at the grain boundaries during HIP hinders grain growth and strengthens the grain boundaries, together leads to a transgranular-dominant fracture mode. As a result, the achieved Ce-TZP ceramic simultaneously reaches a high flexural strength of 770.90 ± 76.06 MPa and an excellent fracture toughness of 11.96 ± 1.31 MPa·m1/2, which are 48% and 29% higher, respectively, compared to the pressureless-sintered samples. This method is expected to enable broader applications of pure Ce-TZP ceramics and to be further extended for designing and manufacturing densified and fine-grained components with complex structures. • Densified pure Ce-TZP ceramics with nanograins of about 420 nm is successfully achieved without introducing other dopants. • High strength of 770.90 ± 76.06 MPa and high toughness of 11.96 ± 1.31 MPa·m1/2 are simultaneously achieved in pure Ce-TZP. • The combination of stereolithography and sinter-HIP can be a universal way for dense, nanosized oxide ceramic parts design. [ABSTRACT FROM AUTHOR]

DC microgrids, considered building blocks of smart grid technologies, are subjected to small-signal instability due to the extensive introduction of power electronics devices. Therefore, in this paper, a sequence Virtual Filter (VF) controller, which considers not only the longitudinal virtual parameters but also the lateral capacitance and resistance, is first developed to increase the flexibility of system stability adjustment compared to the Virtual Impedance (VI) controller. Then, as distribution feeders are normally unbalanced and the application of the proposed sequence VF controller may amplify the distortion of imbalances on DC voltage, a novel Reference Current Generation (RCG) strategy considering the VF controller is proposed for Grid-Connected Converter (GCC) to improve DC microgrid power quality. The double-frequency fluctuation of the DC-link voltage is eliminated by regulating the oscillation of the active power flowing into the converter instead of the Point of Common Coupling (PCC) to 0. The PSCAD simulation results illustrate that the sequence VF controller can enhance the stability adjustment since, in some cases, the system can only be stabilized by adjusting lateral parameters. On the other hand, the proposed RCG strategy can significantly reduce DC voltage fluctuations compared to the traditional approach. Furthermore, incorporating the proposed strategy with the sequence VF controller offers greater flexibility in reducing the negative-sequence current while maintaining a power transfer capacity for GCCs in a master–slave-based DC microgrid, comparable to that of the traditional strategy. • Develop a sequence VF controller for GCC operating under unbalanced conditions to increase the flexibility of stability adjustment compared to the VI controller. • Propose a novel RCG strategy considering the sequence VF controller to improve the power quality of DC microgrids interconnected with unbalanced grids. • Simulation results demonstrate the effectiveness of the proposed controllers. Furthermore, the proposed controllers offer greater flexibility in reducing the negative-sequence current while maintaining power transfer capacities for GCCs in a master-slave-based DC microgrid, comparable to that of the traditional strategy. [ABSTRACT FROM AUTHOR]

• A risk model for cognitive impairment in the older Chinese inpatients was built. • Age, diabetes, depression and educational level were included in this model. • The prediction model had a high sensitivity (86.2%) and a low specificity (59.4%). • It is helpful to "identify" high risk patients rather than "rule out" those at low risk. Early diagnosis of cognitive impairment is important but difficult. Prediction models may work as an efficient way to identify high risk individuals for this disease. This study aimed to develop a simple and convenient model to identify high-risk individuals of cognitive impairment in the older Chinese inpatients. We enrolled 1300 inpatients aged 60 years or above from the department of geriatrics of the First Affiliated Hospital of Chongqing Medical University during 2013 to 2017. The model for cognitive impairment was established in the developing cohort of 1100 participants and tested in another validating cohort of 200 participants. Logistic regression analyses were used to identify the candidate variables of cognitive impairment. Receiver operating curve was adopted to validate the model. Logistic regression analyses showed that increasing age, diabetes, depression and low educational level were independently associated with cognitive impairment. The model was generated in the following way: P model = ey/(1 + ey), where y = −6.874 + 0.088 * age + 0.317 * diabetes + 0.647 * depression + 0.345 * education level. The value of P model indicates the probability of cognitive impairment for each patient. The present model proved to be a reliable marker for identifying people at high risk of cognitive impairment (area under curve = 0.790, 95% CI = 0.728–0.852, p < 0.001). It had a high sensitivity (86.2%) but a relatively low specificity (59.4%). It may be helpful to "recognize" those at high risk of cognitive impairment rather than "rule out" those at low risk of this disease. [ABSTRACT FROM AUTHOR]

• Intravenous tirofiban can significantly improve mortality and functional outcomes at 90 days. • Intravenous tirofiban is safe, whatever monotherapy or combined intravenous with intra-arterial tirofiban. • Mechanical thrombectomy can reduce mortality, but the outcome is not significant in ballooning or stenting. The role of continuous intravenous administration of tirofiban in endovascular therapy is still unclear. This meta-analysis aims to evaluate the 90-day functional prognosis in acute ischemic stroke patients (AIS) treated by endovascular treatment and intravenous administration of tirofiban. We searched PubMed, Embase, and CENTRAL databases with the subject terms "tirofiban", "brain ischemia", and some related free words. Inclusion criteria were: (1) cohort study or randomized control trials; (2) AIS patients who received endovascular therapy; (3) the intervention or exposure was intravenous tirofiban monotherapy or combined with intra-arterial tirofiban; (4) containing data on modified Rankin Scale at 90 days and including at least one of the following indicators: mortality, symptomatic intracranial hemorrhage (sICH), intracranial hemorrhage (ICH), and recanalization. A summary odds ratio was calculated. Twelve eligible studies, consisting of 3268 AIS participants, were identified. There was a significant trend of favorable outcomes (measured by mRS at three months) in the tirofiban group (ORs = 1.36; 95% CI = 1.09–1.70). In addition, compared with the non-tirofiban group, intravenous tirofiban was significantly associated with decreased risk of 90-day mortality (ORs = 0.73; 95% CI:0.59–0.89) and increased recanalization rate (ORs = 1.50; 95% CI:1.08–2.09) but no significant difference in rates of sICH (ORs = 0.93; 95% CI = 0.70–1.24) or ICH (ORs = 0.84; 95% CI = 0.62–1.15). Intravenous tirofiban appears to be safe and effective when used following intra-arterial tirofiban or as monotherapy in AIS patients treated by endovascular therapy, which can improve the 90-day functional outcome, decrease the 90-day mortality and increase the possibility of early recanalization without increasing rates of sICH and ICH. [ABSTRACT FROM AUTHOR]

• The antifreeze PVA/CNF-H 2 SO 4 gel electrolyte was constructed through hydrogen bond crosslinking, and the resulting material exhibited a significant reduction in its freezing point, reaching −77.35 °C. • The construction of a two-dimensional porous Ti 3 C 2 T x electrode enhances the rate performance and pseudocapacitance behaviour of MXene material at low temperatures. • The maximum areal energy and power densities of our C7-SSC achieve 113 μWh cm-² and 0.4 μW cm-² at −50 °C, respectively, exceeding the performance of the majority of state-of-the-art devices. The electrochemical performance of aqueous electrolytes at low temperatures is frequently suboptimal due to their low freezing point (0 °C). In this study, we constructed MXene-based ultra-low temperature polyvinyl alcohol/nanocellulose-H 2 SO 4 (PVA/CNF-H 2 SO 4) hydrogel electrolytes utilising hydrogen bonding between water molecules and nanocellulose. The process results in a reduction in the amount of free water present in the hydrogel electrolyte, lowering its freezing point to -77.35 °C. PVA/CNF-H 2 SO 4 -based solid-state supercapacitors (C7-SSC) demonstrate a capacitance of up to 813 mF cm-2 at -50 °C, exhibiting high-rate performance at low temperatures. The capacitance remains at 45 F g-¹ at a current density of 20 A g-¹. The maximum areal energy and power densities of our C7-SSC achieve 113 μWh cm-² and 0.4 μW cm-² at -50 °C, respectively, surpassing the majority of state-of-the-art devices. This work provides new insights into MXene-based hydrogel manufacturing and expands the range of potential applications for such materials. [Display omitted] [ABSTRACT FROM AUTHOR]

• The hollow cubic octahedral structure of Fe 3 O 4 were successfully prepared by a simple template method. • The hollow cubic octahedral structure of Fe 3 O 4 exhibits improved electromagnetic wave properties compared with previous works. • The mechanism of EMW absorption was explored by experimental and theoretical study. The unique nanostructure combined with high dielectric and magnetic losses is essential for electromagnetic wave (EMW) attenuation in microwave-absorbing materials (MAM). In this paper, using cubic octahedral Cu 2 O as a template, we synthesized hollow cubic octahedral Fe(OH) 3 at first. After annealing at 450 °C, the hollow cubic octahedral structure Fe 3 O 4 could be obtained. When the filling ratio was 40 %, the minimum reflection loss (RL min) reached -66.08 dB, and the maximum effective absorption bandwidth (EAB) was 5.38 GHz at a thickness of 1.84 mm, exhibiting improved EMW properties compared with previous works. The hollow cubic octahedral structure of Fe 3 O 4 enhances EMW absorption characteristics, which is attributed to abundant dipole polarization, interface polarization, and good conduction loss. These results indicate that Fe 3 O 4 with the hollow cubic octahedral structure can be used as potential candidates for efficient and broadband EMW absorbers. [Display omitted] [ABSTRACT FROM AUTHOR]

Graphical abstract Fe 3 O 4 -C 3 N 4 -Ag 2 MoO 4 ternary system showed superior hydroxyl radical productivity and considerable photocatalytic performance. Highlights • Novel Fe 3 O 4 -C 3 N 4 -Ag 2 MoO 4 ternary system was successfully synthesized. • Fe 3 O 4 -C 3 N 4 -Ag 2 MoO 4 ternary system showed superior hydroxyl radical productivity. • Fe 3 O 4 -C 3 N 4 -Ag 2 MoO 4 ternary system efficiently facilitated the separation of charge carriers. • Fe 3 O 4 -C 3 N 4 -Ag 2 MoO 4 ternary system remarkably enlarged the light absorption range. • The possible OH generate procedure of superior photocatalyst was discussed. Abstract Novel Fe 3 O 4 -C 3 N 4 -Ag 2 MoO 4 series photocatalysts were designed and successfully synthesized. UV–vis diffuse reflectance spectra (DRS) indicated that the Fe 3 O 4 -C 3 N 4 -Ag 2 MoO 4 ternary system efficiently enlarged the light absorption range from 360 nm to 550 nm in comparison with that of pristine Ag 2 MoO 4. The hydroxyl radicals (OH) probe experiment suggested that the formation of C 3 N 4 -Ag 2 MoO 4 heterojunction efficiently produced the powerful OH, and the load of Fe 3 O 4 further increased the amount of OH. The photocatalytic performances of as-prepared samples were evaluated by degrading 4-Chlorophenol (4-CP), which only can be degraded in the presence of OH radicals. The degradation results suggested that Fe 3 O 4 -C 3 N 4 -Ag 2 MoO 4 ternary system showed outstanding photocatalytic performance in comparison with that of C 3 N 4 -Ag 2 MoO 4 , and inactive Ag 2 MoO 4. The mechanism of enhanced OH productivity was also discussed. This study proved that novel Fe 3 O 4 -heterojunction system could efficiently enhance the light harvesting and the productivity of OH, which could be a potential strategy for enhancing the photocatalytic performance. [ABSTRACT FROM AUTHOR]

This paper describes a 12–27 GHz VGA with low phase shift variation and dB-linear gain. A pre-distortion technique for extending the gain tuning range is employed to allow a dB-linear dynamic range of 31 dB, and a compensation structure for reducing the phase shift variation is adopted to make the phase shift varies less than 4° within the entire gain range. Besides, a DAC cell is innovatively introduced to achieve the dB linearity and low phase shift variation balance. A fourth-order LC-ladder filter is used for input matching and a peak inductor technique is used to broaden bandwidth of the VGA. The proposed variable gain amplifier operating in Ku and K bands is implemented in 0.18 μm BiCMOS technology. The simulation results show that the input and output return loss are less than −10 dB in the whole work frequency band, an IIP3 of −2.8 dBm, an IP 1dB of −12 dBm and a power consumption of 62.1 mW are achieved at maximum gain mode in center frequency. [ABSTRACT FROM AUTHOR]

Long-term exposure experiments with single and combined pollutants of copper (Cu)/perfluorooctane sulfonate (PFOS) were conducted to explore the influence on activated sludge in SBRs. Compared with the control, the removal of organics, nitrogen and phosphorus in the presence of PFOS exhibited no apparent difference, but reduced in different degrees when Cu and Cu/PFOS existed. PFOS exposure deteriorated the settling performance of activated sludge with SVI value and amount of extracellular polymeric substance (EPS) increasing, but posed little impacts on microbial activity (dehydrogenase, protease) and antioxidant activity (SOD, CAT). Under Cu and Cu/PFOS loading, dehydrogenase and protease activity were observed to decrease as well as SOD and CAT activity. The sequencing results revealed that bacterial richness and community diversity reduced under Cu and Cu/PFOS exposure. Overall, adverse effect of combined pollution was lower than that of single Cu in long-time due to antagonistic effect existed between Cu and PFOS. [ABSTRACT FROM AUTHOR]

Background: The effectiveness and safety of the infusion of ice-cold fluids for prehospital hypothermia in cardiac arrest victims are unclear. This study assessed its effects in adult victims of out-of-hospital cardiac arrest.Methods: An online search of PubMed and Cochrane Library databases was performed. Cooling methods were limited to ice-cold fluid perfusion. Randomized controlled trials were included in this review. The main outcomes were body temperature at hospital arrival, survival to hospital discharge, neurological recovery, incidence of pulmonary edema, and the rate of rearrest.Results: Among 1155 citations, 5 studies were included in this meta-analysis. The pooled analysis of these studies revealed no differences in survival to hospital discharge, favorable neurological outcomes, and incidence of pulmonary edema between the treatment group and control group. There were significant differences in body temperature at hospital arrival (I2 = 0.0%, χ2 = 2.58, MD = -0.760, 95% confidence interval = -0.938 to -0.581, P < .001) and the rate of rearrest (I2 = 0.0%, χ2 = 0.69, 95% confidence interval = 1.109 to 1.479, P = .031).Conclusions: Prehospital therapeutic hypothermia induced by intravenous infusion of ice-cold fluids in patients with out-of-hospital cardiac arrest decreased body temperature at hospital arrival but did not improve survival to hospital discharge and favorable neurological outcomes. Ice-cold fluid infusion did not increase the incidence of pulmonary edema but increased the incidence of rearrests. [ABSTRACT FROM AUTHOR]

This study put forward a one-step carbonization method by concentrated sulfuric acid to prepare garlic peel derived biochar, and the synthetic conditions were optimized by L 16 (45) orthogonal experiments. Notably, in order to study the differences between the proposed synthetic method and the conventional pyrolysis method, the concentrated sulfuric acid carbonized garlic peels biochar (CSGPB) was compared with pyrolysis derived garlic peel biochar (HTGPB) in characterization and adsorption capacities for Enrofloxacin (ENR). Results showed that CSGPB exhibited more graphite-like structures with more active functional groups on the surface, and the equilibrium adsorption capacity of CSGPB (142.3 mg g−1) was 13.7 times of HTGPB (10.4 mg g−1) under identical conditions. Moreover, the adsorption behaviors including adsorption kinetics, isotherms and thermodynamics of CSGPB for ENR were fully investigated and discussed. Based on the above experiments, density functional theory (DFT) simulations were performed to reveal the interfacial interaction and adsorption mechanism. Results showed π-π interaction between quinolone moieties of ENR and graphite-like structures in CSGPB might be the dominant mechanism. As for the functional groups, the adsorption energies were −40.46, −15.21 and −5.96 kJ mol−1 for –SO 3 H, –OH and –COOH, respectively, which indicated –SO 3 H was the most active functional groups on the surface of CSGPB. This study provided a new sustainable perspective for the design of efficient biochars, and explored the interfacial interaction mechanism of antibiotics removal on biochars. [Display omitted] • A one-step carbonization method was proposed to prepare garlic peel (GP) biochar. • The synthetic conditions were optimized by L 16 (45) orthogonal experiments. • Concentrated H 2 SO 4 carbonized GP biochar was compared with pyrolyzed GP biochar. • DFT simulations were performed to reveal the interfacial interaction mechanism. • The π-π interaction between Enrofloxacin and CSGPB might be the dominant mechanism. [ABSTRACT FROM AUTHOR]

Small-signal stability analysis is essential for the safe operation and parameter design of power electronic-dominated grids. Unbalanced conditions introduce more frequency-coupling terms, which are unneglectable in the stability assessment. This paper proposes a novel Linear Time-Periodic (LTP) theory-based stability analysis method and focuses on grid-connected voltage-source converters (VSCs) without improved unbalancing controls. Firstly, the analysis of fundamental solutions of the LTP system reveals that each LTP mode is characterized by a unique damping factor and multiple oscillation frequencies, defined by LTP eigenvalues and related transformation vectors, i.e., (λ i , V i (t)). Then, a method for calculating (λ i , V i (t)) is proposed using the characteristic matrix of the Harmonic State-Space (HSS) model. An iterative sorting method based on the time-domain interpretation of HSS eigenvalues/eigenvectors is proposed to determine accurate (λ i , V i (t)) in the case of the minimum truncation order. Finally, generalized definitions and calculation methods of the widely used indicators for modal analysis are presented to assess system stability and guide the parameter design. Numerical and simulation results verify the proposed stability analysis method and indicate its advantages compared to the existing Floquet and HSS methods. • Proposes a novel LTP theory-based time-domain stability analysis method. • Fundamental solutions of the LTP system are analyzed, revealing that each LTP mode is characterized by a unique damping factor and multiple oscillation frequencies, defined by LTP eigenvalues and related transformation vectors. • A method for computing LTP eigenvalues and related transformation vectors is proposed using the characteristic matrix of the HSS model. • Generalized definitions and calculation methods of the damping ratio, PFs, and EPSs for LTP systems are proposed for the guidance of parameter design. [ABSTRACT FROM AUTHOR]

The triple-doped Yb/Er/Pr-Bi 2 WO 6 photocatalyst presented the optimal degradation performance under visible light irradiation. The enhanced catalytic property mechanism was ascribed to the abundant superoxide anions and hydroxyl radicals production and the inhibition of charge carriers recombination. Yb/Er/Pr-BWO + hv → e- + h±. O 2 + e- → O 2 − 2e- + h± + O 2 − → HO 2. HO 2 + e- → HO 2 − HO 2 − + h± → H 2 O 2. Pr3+ + H 2 O 2 → Pr4+ + OH− + OH. H 2 O 2 + OH → HO 2 + H 2 O. Pr4+ + HO 2 → Pr3+ + O 2 + H±. H 2 O + h± → OH + H±. [Display omitted] • A novel Yb/Er/Pr-Bi 2 WO 6 catalyst was synthesized using one-step hydrothermal method. • TUnder visible light illumination, the Yb/Er/Pr triple-doped Bi 2 WO 6 exhibited outstanding photocatalytic activity. • The photo-degradation efficiency of 2.0%Yb/2.0%Er/2.0%Pr-Bi 2 WO 6 was 8.1 times for Congo Red than that of individual Bi 2 WO 6. • The mechanism of enhanced photocatalytic performance was due to thepromoted reactive oxide species production and photocarrier separation. • Provides a feasible strategy for improving photocatalytic activity of catalysts and deducing the possible mechanism. Superoxide anions (O 2 −) and hydroxyl radicals (OH) are vital reactive oxide species (ROS) in the photocatalytic process. In this study, a novel triple-doped bismuth tungstate (Yb/Er/Pr-Bi 2 WO 6) superior photocatalyst was constructed using hydrothermal method. The yield of O 2 − and OH are concurrently boosted by the synergistic effect for Yb/Er/Pr triple-doping. The X-ray photo-electron spectra confirmed the existence of oxygen vacancy and Pr4+/Pr3+ redox center, which can act as trap electron center to produce more O 2 − and promote electron-holes pairs separation. Meanwhile, Yb and Er doping observably regulated the valence band position of Bi 2 WO 6 from 2.39 V to 2.63 V, which is beneficial to produce more OH. Comprehensive characterization illustrate that Yb/Er/Pr-Bi 2 WO 6 shows superior performance in photocatalytic activity, photocarrier separation and light absorption efficiency compared with the pristine Bi 2 WO 6 , single-doped Bi 2 WO 6 and co-doped Bi 2 WO 6. The research provides a simple and valid method for enhancing the visible-light-responding photocatalytic property and exploring the possible enhanced photocatalytic performance mechanism. [ABSTRACT FROM AUTHOR]

• The Yb3+/Nd3+ - Bi 2 WO 6 was synthesized using hydrothermal method. • The degradation efficiency of 1.5%Yb3+/0.5%Nd3+-Bi 2 WO 6 was 3.7 times than that of Bi 2 WO 6. • The mechanism of improved photocatalytic proporty was ascribed to the extension range of visible light and the synergistic effect of oxygen vacancies and Yb3+/Yb2+ redox center. • Provide a new concept rational design and acquirement of visible-light-driven photocatalyst. A novel Yb3+/Nd3+-Bi 2 WO 6 photocatalyst with oxygen vacancies was synthesized through one-step hydrothermal method. The 1.5%Yb3+/0.5%Nd3+-Bi 2 WO 6 exhibited an outstanding performance, whose decomposition efficiency of Rhodamine B was 3.7 times higher than that of bare Bi 2 WO 6. The crystal structure, morphology, chemical state and optical properties were systematically investigated to reveal the mechanism of its enhanced photocatalytic performance. Its excellent visible light absorption and an absorption peak at 584 nm due to the excitation of Nd3+ were confirmed by the UV-Vis diffuse reflectance spectra of composite samples. Meanwhile, not only the existence of dopants was confirmed by the X-ray spectroscopy, but the in-built Yb3+/Yb2+ redox center was also revealed. Moreover, the formation of oxygen vacancies and Yb3+/Yb2+ redox center could effectually restrict the recombination of photo-generated electron-hole pairs, which could be demonstrated by photoluminescence characterization. Consequently, the mechanism of an enhanced photocatalytic performance was speculated about the extension range of visible light and the synergistic effect of oxygen vacancies as well as the redox center. This study provides a new concept, a rational design and the acquirement of a high-efficiency visible-light-driven photocatalyst. [ABSTRACT FROM AUTHOR]