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Objectives: The present study aimed to simulate the influence of palatal extensions for custom-made mouthguards (MGs) on protecting dentoalveolar structures and to provide a theoretical basis for designing a comfortable MG. Materials and methods: Based on finite element analysis (3D-FEA), five groups of maxillary dentoalveolar models of wearing MGs were established: no MG on palatal side (NP), on palatal gingival margin (G0), 2 mm from the palatal gingival margin (G2), 4 mm from the palatal gingival margin (G4), 6 mm from the palatal gingival margin (G6), and 8 mm from the palatal gingival margin (G8). A cuboid was created to simulate the solid ground impacted in falls, a gradually increasing force was applied from 0 to 500 N on the vertical ground, and the distribution and peak values of the Critical modified von-Mises stress, maximum principal stress, and displacement of dentoalveolar models were calculated. Results: Stress distribution range, stress, and deformation peak value of dentoalveolar models increased as the impact strength increased, at 500 N. Maximum critical modified von-Mises stress, peak maximum principal stress and maximum displacement of dentoalveolar models G4, G3, G2, G1, G0, and NP were 154.5 MPa, 154.5 MPa, 154.4 MPa, 154.7 MPa, 154.4 MPa, and 154.7 MPa; 191.65 MPa, 192.11 MPa, 191.62 MPa, 191.81 MPa, 191.56 MPa, and 191.62 MPa; and 88.78 μm, 88.57 μm, 88.19 μm, 88.67 μm, 88.43 μm, and 89.04 μ, respectively. However, the position of the MG palatal edge had little effect on stress distribution, stress, and deformation peak values of the dentoalveolar models. Conclusions: Different extension ranges of the MG palatal edge have little effect on the protective effects of MGs on maxillary teeth and maxilla. An MG with palatal extension on the gingival margin is more appropriate than other models and may help dentists to design a suitable MG and increase its usage. Clinical relevance: MGs with palatal extensions on the gingival margin may provide a more comfortable wearing experience for individuals involved in sports and encourage increased MG usage. [ABSTRACT FROM AUTHOR]

Ligand–RNA interaction assay provides the basis for developing new RNA-binding small molecules. In this study, fluorescent copper nanoclusters (CuNCs) were first prepared using two kinds of HIV-1 RNA targets, rev-responsive element (RRE) and transactivator response element (TAR) RNA, as new templates, and it was found that the fluorescence of the single RNA-templated CuNCs was negligible. Using neomycin as a model drug, the fluorescence could be augmented (approximately 6 times) for the neomycin/RNA-templated CuNCs. Thus, a novel method was developed for ligand–RNA interactions by observing the fluorescence changes in CuNCs prepared using RNA before and after the addition of ligands. The preparation parameters of neomycin/RNA-CuNCs were optimized. The as-prepared CuNCs were characterized using UV–vis spectroscopy, fluorescence spectroscopy, and high-resolution transmission electron microscope. Circular dichroism spectral analysis showed that RRE and TAR were inclined to form a double-stranded structure after interaction with neomycin, which was more conducive to the formation of CuNCs. The interactions of neomycin and three test drugs (amikacin, gentamicin, and tobramycin) with RNA were investigated using the proposed method, and the binding constants and number of binding sites were obtained through theoretical calculations. This study provides a novel approach for ligand–RNA interaction assays. • HIV-1 RNA-templated fluorescent CuNCs were prepared for the first time. • Fluorescence enhancement of ligand/RNA-templated CuNCs was discovered. • A novel method was developed for ligand–RNA interactions based on RNA-templated CuNCs. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new oxygen vacancy-rich B-Ni/CP is fabricated via a simple electrodeposition method. • The Ni2+ center has a low oxygen coordination with a pyramidal symmetry. • The B-Ni/CP exhibits high electrocatalytic activity for OER. Ni-based compounds represent promising candidates as high-performance electrocatalysts for the oxygen evolution reaction (OER) in alkaline media. Here, a new Ni oxide electrocatalyst developed via a simple electrodeposition method is reported, exhibiting enhanced catalytic activity for OER. Structural and activity analysis of the fresh and post-reaction samples reveals that the Ni2+ center has low coordination with pyramidal symmetry (NiO 5). The bulk metallic Ni readily undergoes oxidation under OER conditions to generate more low-coordinated Ni2+ and high-valence state Ni (Ni3+) species, thereby facilitating the OER reaction. This study provides new insight into the active structure of Ni-based oxide electrocatalysts and offers a simple pathway for the design and development of cost-effective and high-performance electrocatalysts for applications in OER. [ABSTRACT FROM AUTHOR]

Abstract Profound progress has been made in bio-rejuvenators to enhance aged asphalt's low temperature performance and reduce its high temperature viscosity. However, limitation still exists in the knowledge how long service life of rejuvenated asphalt is and whether regeneration is effective since aging behavior of rejuvenated asphalt is neglected. Furthermore, aging evaluation is based on different tests dependent on temperature, which may lead to various results. This study aims to evaluate the aging behavior of bio-rejuvenated Pen70 and SBS modified asphalts using internal aging indexes that characterize the physical property. Original Pen70 and SBS asphalts under identical aging conditions were set as the control group. Fourier transform infrared spectroscopy test (FTIR) was conducted to quantify aging extent through oxidation aging functional groups. Activation energy was achieved through rotational viscometer (RV). Dynamic shear modulus was acquired through dynamic shear rheological test (DSR) and characterized by two springs, two parabolic elements, and one dashpot (2S2P1D) model. For both Pen70 and SBS, the two potential aging indexes related with activation energy and viscosity of dashpot separately were found linearly correlated with related chemical aging functional groups. Through comparison, it indicates that bio-rejuvenation was a process of physical blending. It couldn't restore the crosslinking structures of SBS polymers. Besides, the physical property of bio-rejuvenated Pen70 degenerated faster, while that of bio-rejuvenated SBS stayed stable. A benefit period was proposed for the rejuvenation of Pen70 while the rejuvenation of SBS was not bound by time. Further work is needed to validate findings in the present study. Graphical abstract Image 10385 [ABSTRACT FROM AUTHOR]

Atherosclerosis is a chronic disease characterized by the accumulation of lipids and fibrous elements in the large arteries, which is the principal cause of coronary artery disease. Dysregulated exosomal microRNA (miRNA) levels in serum have been identified in patients with various diseases, including CAD. In the present study, nine candidate miRNAs were detected in the plasma exosome from 42 patients with coronary atherosclerosis, and a higher expression of miR-30e and miR-92a was identified in patients. Following bioinformatics analysis and confirmation through immunoblotting, it was demonstrated that ATP binding cassette (ABC)A1 is a direct target of miR-30e, and miR-92a. Furthermore, a negative correlation was identified between plasma miR-30e and ABCA1, or miR-30e and cholesterol. Thus, the results of the present study suggest that the miR-30e level in exosomes from serum may have the potential to be a novel diagnostic biomarker for coronary atherosclerosis. [ABSTRACT FROM AUTHOR]

[Display omitted] The collection efficiency (N eff) of rotating ring-disc electrode is diffusion- and reaction-dependent. The collection process at ring electrode can be used to assess the transient binding of redox intermediate with electrode surface, more specifically, the intermediate-electrode interaction within the double layer. The ability to capture the behavior of redox intermediate will facilitate understanding of electrocatalytic process on electrode surface • Revealed the fundamental dependence of the collection efficiency on diffusion. • Established a new affinity index for redox intermediate-electrode interaction. • Formulated an analytical solution to surface kinetics with practical application. • Benefits and limitations of the steady-state analytical model discussed in depth. The interaction of redox intermediate with electrode surface is a seldom explored realm yet an interesting facet in electrocatalysis. This work demonstrates, for the first time, the analytical use of rotating ring-disc electrode to measure the intermediate-electrode interaction in a double-layer model. Our solution to the electro-kinetics reveals the intrinsic dependence of the collection efficiency on the extent of intermediate-electrode interaction, as validated by two redox couples typical of 'outer-sphere' (Fe(CN) 6 3–/Fe(CN) 6 4–) and 'inner-sphere' (dopamine/ dopaminoquinone) nature on Pt and Au electrodes. The experiment with the model systems validates the applicability of the theory, allowing semi-quantitative comparison of the transient binding with different electrode surfaces, while the limitations of the method are also discussed at insightful depth. As a proxy to better understand redox intermediates, the method is set to provide a practical tool and an inspiration to expand the analytical toolset for materials research. [ABSTRACT FROM AUTHOR]

Abstract: Pt nanoparticles (NPs) immobilized on a core–shell hybrid carbon support allow the efficient direct dehydrogenation of n‐butane at low temperatures. The hybrid carbon support is composed of a nanodiamond core and a reinforced ultrathin graphene shell (ND@G), which improves the stability of the anchored Pt NPs against sintering under the reaction conditions. The as‐prepared Pt/ND@G catalyst demonstrates excellent catalytic performance (≈25 % conversion with >95 % selectivity toward olefins) at 450 °C for over 10 h as a result of strong metal–support interactions. The catalyst can also be fully regenerated by postoxidative thermal treatment. [ABSTRACT FROM AUTHOR]

A heterogeneous medium-Mn steel with ultra-high ductility and good strength was designed, which displayed yield strength of 752 MPa, ultimate tensile strength of 1068 MPa, total elongation of 72.4%, and strength-elongation product of 77.3 GPa·%. A unique pre-existing austenite + martensite lamella structure was introduced by warm rolling followed by cold rolling. During annealing, it transformed into a heterogeneous duplex-phase (ferrite and austenite) microstructure with multiple morphologies (lath-like, granular, and block) and a dispersed grain size distribution. The relationships between the microstructural evolution and Mn segregation, deformation mechanisms, and mechanical behavior were characterized. The heterogeneous austenite structure yielded different austenite-stability gradients, which triggered multi-stage transformation-induced plasticity (TRIP) effects during the tensile test, accompanied by the twinning-induced plasticity (TWIP) and microband-induced plasticity (MBIP) effects. Therefore, the synergy of multiple strengthening mechanisms significantly improved the steel ductility without affecting its strength, resulting in better mechanical properties than other medium-Mn steels. • The formation and deformation mechanism of heterogeneous microstructure were investigated in Medium Mn steel. • Mn-lean martensite bands transformed to small granular/lath-like austenite grains and Mn-rich austenite bands transformed to large block austenite grains. • The multiple deformation mechanisms including TRIP effect, TWIP effect and MBIP effect were triggered during deformation. • The product of tensile strength and total elongation of hetero-structured medium Mn steel was up to 77.3 GPa%. [ABSTRACT FROM AUTHOR]

A novel concept of microstructure design involving warm rolling and low-temperature annealing has been proposed to greatly improve the strength-ductility combination of medium Mn steel. The unique transformation induced plasticity has been triggered by firstly microbands and secondly deformation twins, enhancing the ductility significantly and the reasonable dislocation density in non-recrystallized austenite grains increases the yield strength greatly. The individual contribution of solid solution strengthening, grain boundary strengthening, V-precipitates strengthening and dislocation strengthening to yield strength is discussed by constitutive models, in which the tangled dislocation plays a dominant role. Best strength-ductility combination with yield strength (1239MPa), ultimate tensile strength (1341MPa), total elongation (41.8%) and product of strength and elongation (56.1GPa·%) has been obtained, which are comparable and superior to the reported medium-Mn steels. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: LaMnO3+δ and La0.7Ca0.3MnO3 were synthesized from La2O3(La(OH)3), CaCO3 and MnO2 powder mixture with solid-state reaction technique. X-ray diffraction and thermal analysis were employed in the present study on the process of synthesizing of the two compound powders. The kinetic study on solid-state reaction between La2O3 and MnO2 in the powder mixture was isothermally carried out for LaMnO3+δ formation. The result showed that the reaction process was controlled by three-dimensional solid-ionic diffusion. Both Jander and Ginstling-Brounstein model can be used to describe the reaction kinetics satisfactorily. The relevant apparent activation energy values obtained were as great as 205±11 and 189±8kJ/mol. The reaction process of La0.7Ca0.3MnO3 preparation from La2O3, SrCO3 and MnO2 powder mixture was also studied using X-ray diffraction and thermal analysis. The result indicated that the following steps composed the overall reaction: the decomposition of the reactant; the formation of La1−x Ca x MnO3+δ ; La2O3 and Mn3O4 reacted with La1−x Ca x MnO3 to form final La0.7Ca0.3MnO3 phase. The latest step was the most time-consuming one among others in the overall reaction. [Copyright &y& Elsevier]

Abstract: The high-temperature behavior of O-orthorhombic LaMn0.95O3.02 in air was studied by using high-temperature XRD combined with TG/DSC analysis. A phase transition from O-orthorhombic to rhombohedral was found between 573 and 773K. TG/DSC curves showed a weight gain and no DSC peaks within the temperature range of the phase transition. The phase transition is attributed to the change of oxygen content in LaMn0.95O3.02. The lattice thermal expansion coefficients of rhombohedral LaMn0.95O3.02 were calculated using lattice parameters. [Copyright &y& Elsevier]

Abstract: La1−x Sr x Co1−y Ga y O3−δ (x =0.3 and 0.5, y =0.1) were synthesized using solid-state reaction technique, and the phases formed during synthesis processes were investigated by powder XRD measurements. LaSrGa3O7 and the rhombohedral phase coexisted at 1473 K for the system with a molar ratio of La/Sr/Co/Ga equal to 0.7/0.3/0.9/0.1. For the system with molar ratio of La/Sr/Co/Ga equal to 0.7/0.3/0.7/0.3, LaSrGa3O7 and the rhombohedral phase coexisted at 1673 K, while LaSrGaO4 and the rhombohedral phase coexisted at 1873 K. Crystal structural parameters of La0.7Sr0.3Co0.9Ga0.1O3−δ and La0.5Sr0.5Co0.9Ga0.1O3−δ were obtained through a route of Rietveld refinement performed using X-ray powder diffraction data, the results showed that they are rhombohedral distorted perovskite with R3¯c symmetry. [Copyright &y& Elsevier]

Depressed patients often suffer from sleep disturbance, which has been recognized to be responsible for glymphatic dysfunction. The purpose of this study was to investigate the coupling strength of global blood‑oxygen-level-dependent (gBOLD) signals and cerebrospinal fluid (CSF) inflow dynamics, which is a biomarker for glymphatic function, in depressed patients and to explore its potential relationship with sleep disturbance by using resting-state functional MRI. A total of 138 depressed patients (112 females, age: 34.70 ± 13.11 years) and 84 healthy controls (29 females, age: 36.6 ± 11.75 years) participated in this study. The gBOLD-CSF coupling strength was calculated to evaluate glymphatic function. Sleep disturbance was evaluated using the insomnia items (item 4 for insomnia-early, item 5 for insomnia-middle, and item 6 for insomnia-late) of The 17-item Hamilton Depression Rating Scale for depressed patients, which was correlated with the gBOLD-CSF coupling strength. The depressed patients exhibited weaker gBOLD-CSF coupling relative to healthy controls (p = 0.022), possibly due to impairment of the glymphatic system. Moreover, the gBOLD-CSF coupling strength correlated with insomnia-middle (r = 0.097, p = 0.008) in depressed patients. Limitations This study is a cross-sectional study. Our findings shed light on the pathophysiology of depression, indicating that cerebral waste clearance system deficits are correlated with poor sleep quality in depressed patients. • All participants had a strong gBOLD-CSF coupling, which correlated with their age. • Depressed patients had significantly weaker gBOLD-CSF coupling than healthy controls. • Strength of gBOLD-CSF coupling correlated with insomnia-middle in depressed patients. [ABSTRACT FROM AUTHOR]

• Four different layers were found in the asphalt phase of SFP through microscale tests. • A micromechanical model considering interlocking and stiffening effect was proposed for SFP. • The equivalent modulus of asphalt phase considering interlocking effect was cross-checked with NI test. Semi-flexible pavement (SFP) has been promoted to apply in pavement engineering mainly for its excellent performance in rutting resistance. However, due to the material characteristics of three-phase heterogeneous phase and the structural characteristics of dense skeleton interlocking structure, the microstructure of semi-flexible pavement material is complicated, greatly influencing the mechanical properties of the material. This research aims to identify the two characteristics of SFP employing micromechanical models as well as nano-techniques, including nanoindentation (NI), Scanning Electron Microscope (SEM) and energy dispersive spectrum analysis (EDS). Two interlocking factors were introduced in the three-phase micromechanical model to characterize the interlocking effect. Identification of the asphalt mastic phase in SFP was implemented as the basis of stiffening correction in the micromechanical model. Because four different layers were found in the asphalt phase of SFP that was difficult to simulate, a general stiffening correction was used in the improved micromechanical model. The final model considering the interlocking and asphalt stiffening effects can characterize the property of SFP well. It was found that grouting cement has an enhancement function on the viscoelastic interlocking effect while does little on the elastic interlocking effect. Meanwhile, more grouting cement will lead to more asphalt-cement stiffening effect. An equivalent dynamic modulus of the asphalt phase-phase from the micromechanical model was proposed in the end, which has been proven corresponding to the experimental results of NI test. [ABSTRACT FROM AUTHOR]

Background: As global aging intensifies, older adults with chronic diseases are of increasing concern. Home and community-based services (HCBSs) have been proven to promote self-rated health (SRH) in older adults, but no research explored the associations between the use of overall HCBSs, three different types of HCBSs (health care, daily care, and social support services) and SRH among older adults with chronic diseases. Consequently, this study applies a national publicly available database to examine these associations among older adults with chronic diseases. Methods: 8,623 older adults with chronic diseases (≥ 60 years old) were included in this study. SRH was evaluated applying a concise question with a 1 − 5 scale. HCBSs utilization was assessed through the question, "What kind of HCBSs were used in the community?". Univariate general linear regression models aimed to compare the mean values of SRH in terms of HCBSs utilization in each group. This study is a cross-sectional study design and the relationship between HCBSs utilization and SRH was assessed by multilevel linear regression. Results: The mean score for SRH among the respondents was 3.19, of whom 20.55% used one or more HCBSs, 19.47% utilized health care services, 2.44% utilized social support services, and only 0.55% utilized daily care services. The use of HCBSs was found to be linked to SRH among older adults with chronic diseases (β = 0.085, SE = 0.025, p < 0.001). SRH among older adults with chronic diseases was strongly linked to the use of health care and social support services (β = 0.068, SE = 0.025, p < 0.001; β = 0.239, SE = 0.063, p < 0.001, respectively). However, there was no significant association between the use of daily care services and SRH among older adults with chronic diseases. Conclusion: This study revealed that HCBSs utilization was positively and significantly linked to SRH in Chinese older adults with chronic diseases. Furthermore, this study supposes the low utilization of social support and daily care services may be due to a mismatch between supply and demand. The government should offer the targeted HCBSs for older adults with chronic diseases according to their unique features to enhance their health status. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The 2S2P1D model is suitable for SFP. • A larger porosity in PA means a greater effect of skeleton interlock on loss modulus. • Grouting cement had a negative effect on the loss modulus at low temperatures. • Physiochemical stiffening effect and imperfect interface exist between PA and cement skeletons. • A larger porosity leads to a more stable interlock effect with the frequency increasing. Abstract Semi-flexible pavement (SFP) has been promoted to apply in pavement engineering mainly for its excellent performance in rutting resistance. Since the reinforcing mechanism of its stiffness and strength is still ambiguous, this paper aims to investigate the reinforcing mechanisms of SFP at meso-scale. SFP was regarded as a double skeleton structure (open graded asphalt skeleton and grouting cement skeleton) and three main reinforcing mechanisms were characterized on the basis of the Mori-Tanaka model (M-T), including matrix modulus, cement filling effect and double structure interlock. During the process, the matrix of SFP was redefined as asphalt mixture without effect of cement-filling air voids. The behavior of the imaginary matrix was obtained through back-calculation in M-T model. The two springs, two parabolic elements, and one dashpot (2S2P1D) model was utilized to characterize viscoelastic behavior and two interlock factors were established to amend interlock effect. The results may demonstrate the existence of physiochemical stiffening effect of grouting cement and imperfect interphase between the two skeletons. SFP with matrix of three different original porosities were compared during the prediction process. It was found that the reinforcing rate was positively related with original porosity. While the dynamic modulus value of SFP, meaning specially storage modulus value, depended more on the matrix gradation than porosity. And grouting cement had a negative effect on the holistic loss modulus at high frequencies. [ABSTRACT FROM AUTHOR]

Background: Studies have shown a close association between home and community-based healthcare services (HCBHS) utilization and depressive symptoms in older adults. However, no studies have explored the underlying mechanism of this relationship in rural China. This study was designed to evaluate the roles of instrumental activities of daily living (IADL) and marital status in the association between HCBHS utilization and depressive symptoms in Chinese rural older adults. Methods: Data were obtained from the 2018 China Health and Retirement Longitudinal Study, and 5,981 rural respondents (≥ 60 years old) were included. Depression scores were calculated using the ten-item Center for Epidemiological Studies Depression Scale. Moderated mediation analysis was carried out applying Hayes' PROCESS macro (Model 7). Results: HCBHS utilization had a direct and negative effect on depressive symptoms. Furthermore, marital status moderated the association between HCBHS utilization and IADL, which belonged to the indirect influence of the first half on the association between HCBHS utilization and depressive symptoms. HCBHS utilization was associated with IADL in single but not in married respondents. Conclusion: The results demonstrated that marital status moderated the indirect relationship between HCBHS utilization and depressive symptoms, with HCBHS utilization being negatively associated with IADL among single but not married respondents. The government should focus on rural older adults, especially those who are single and have poor IADL function, and improve the provision of HCBHS to alleviate depressive symptoms. [ABSTRACT FROM AUTHOR]

Hybrid materials consisting of few-layer sp 2 carbon supported on Al 2 O 3 can potentially display comparable performance with nanodiamonds for the oxidative dehydrogenation of ethylbenzene. The hybrid structure could be easily prepared by fast coking method using ethanol as a precursor and ɣ-Al 2 O 3 with high specific surface areas as a template. In this case, ɣ-Al 2 O 3 plays the role of 3D support for depositing few-layer graphene-like structure. The hybrid structure exhibiting similar structure with nanodiamonds calcined at high temperature is further used as a metal-free catalyst for the oxidative dehydrogenation of ethylbenzene to styrene. The yield rate of styrene normalized by the specific area on Al 2 O 3 @C is 0.044 mmol m −2 h −1 (TOF = 4.13 h −1 ) which is two times of that on nanodiamonds (0.020 mmol m −2 h −1 , TOF = 3.27 h −1 ). Considering the low cost process and good catalytic performance, the hybrid nanostructure may be a promising candidate to be applied in the oxidative dehydrogenation of ethylbenzene. [ABSTRACT FROM AUTHOR]

MgO–rGO hybrid catalysts with a sandwich structure have been successfully prepared through a simple “solid–solid” method. Obviously enhanced reactivity is observed on the hybrid catalysts in ethylbenzene dehydrogenation reactions, which is attributed to the sandwich structure and the synergistic effect between MgO and rGO. [ABSTRACT FROM AUTHOR]

Abstracts Use of bio-binder could address depletion of petroleum oil, pollution from residue waste, greenhouse gases emissions, and development of sustainable asphalt pavement that is both economically and environmentally friendly. This study investigated the physical and chemical properties of bio-oil rejuvenated asphalt with a series of test. A pre-treatment procedure was introduced to upgrade the biodiesel residue produced from waste cooking oil. Aged asphalt was prepared with a laboratory short-term aging method. The optimal content of the bio-oil was determined by conventional tests and related index, such as penetration, softening point, and ductility, to rejuvenate aged asphalt to its virgin level. Rheological properties, including viscosity, high-temperature rutting resistance, and low-temperature cracking resistance, of virgin, aged, and bio-oil rejuvenated asphalts were then investigated. Afterward, asphalt fraction components, functional groups, and microstructures of virgin, aged and bio-oil rejuvenated asphalts, together with the molecular information of bio-oil, were analyzed with the aid of micro testing techniques. Finally, the moisture susceptibilities were evaluated by conducting micro mechanical experiments. Results clearly demonstrate that bio-oil could soften aged asphalt and improve its low-temperature cracking resistance. Workability was improved due to the reduction of viscosity. Moreover, bio-oil was found to be a complex organic mixture with low molecular weight. Bio-oil was able to compensate aged asphalt for the loss of light components and may also interact with polymer in modified asphalt. Meanwhile, the aggregation of polar components after aging can be mitigated. Thus, the properties of aged asphalt would be enhanced with the addition of bio-oil rejuvenator. However, the anti-moisture performance of bio-oil rejuvenated base (Pen50) asphalt needs to be further improved due to the presence of hydrophilic functional groups and components. In sum, this paper presents the superiorities and potential application challenges of using biodiesel-residue-based bio-oil to rejuvenate aged asphalt. [ABSTRACT FROM AUTHOR]

The present paper reports the first stage of the study by the present group on the thermal decomposition of La2Mo2O9 under lower oxygen partial pressure. The stability of La2Mo2O9 at 1473 K in an oxygen partial pressure $$ (p_{{{\rm O}_{2} }} ) $$ ranges from 2.44 × 10 to 4.33 × 10 Pa was studied by XRD. The results showed that La2Mo2O9 could remain stable in a $$ p_{{{\rm O}_{2} }} $$ range greater than 2.44 × 10Pa. While below this $$ p_{{{\rm O}_{2} }} $$, the formation of several reduced and crystallized molybdates were found. By means of XRD, TEM, SAED, and EDS, the decomposition process of La2Mo2O9 at 1473 K under $$ p_{{{\rm O}_{2} }} $$ of 9.75 × 10Pa was investigated. The intermediate and final products formed during the thermal decomposition were characterized. It was found that the La2Mo2O9 decomposition consisted of two steps. La2Mo2O9 first decomposed to intermediate products like LaMo2O5, La5Mo4O14, and La12Mo6O35 and then to final products like La5Mo3O16 and a new Mo-rich compound. Tilt series of SAED patterns of this new structure were recorded. These measurements were used for the reconstruction of the reciprocal space. The cell attained was monoclinic with parameters: a ≈ 1.195 nm, b ≈ 4.133 nm, c ≈ 1.314 nm, and β ≈ 95°. [ABSTRACT FROM AUTHOR]

Abstract: The effect of oxygen partial pressure () on the electrical conductivity of La2Mo2− x W x O9−δ (x = 0.0, 0.5, 0.7) was investigated from 873 to 1073 K using AC impedance spectroscopy in oxygen, air, argon, and CO–CO2 mixtures with CO volume percentages, 0.5%, 9%, 33% and 50% used for producing lower oxygen partial pressures. The results have shown that the electrical conductivity increases slowly with the decreasing when the CO content is not greater than 0.5 vol.%. has more significant influence on the electrical conductivity of W-doped La2Mo2O9 than on that of undoped La2Mo2O9. For La2Mo1.3W0.7O9, the logσ attained in all atmospheres except oxygen and CO–CO2 mixture with 50 vol.% CO, exhibits a good linear relationship with log . The corresponding slopes attained are as large as 0.019–0.021, much lower than 1/4, suggesting that the enhancement of total electrical conductivity could be mainly due to the increase of ionic conductivity when decreases. XRD and XPS analyses for La2Mo2−x W x O9−δ have confirmed that a small amount of Mo6+ has been reduced to Mo4+ during the electrical conductivity measurements in CO–CO2 mixture with 9 vol.% CO, and further decreasing causes the formation of La7Mo7O30. This may lead to the remarkable changes in their electrical conductivities. A critical value for each compound at a specified temperature between 873 and 1073 K has been found, and below this value the compound would become unstable. The critical values attained at 973 K are as follows: 10−12, 10−15 and 10−17 Pa for La2Mo2O9, La2Mo1.5W0.5O9 and La2Mo1.3W0.7O9 respectively. [Copyright &y& Elsevier]

Abstract: La2−x Ba x Mo2O9−x/2 (x ≤0.18) have been prepared by solid state reaction method. The lattice parameter of La2−x Ba x Mo2O9−x/2 (x ≤0.18) determined by XRD data refinement shows a linear dependence on the dopant Ba content x. For the specimen with a La/Ba molar ratio of 0.18–0.2, additional reflection of secondary phase exists in the XRD pattern, so the value of solubility limit for Ba in La2Mo2O9 is defined in range of 0.18< x <0.2. As the replacement degree of La3+ by Ba2+ increases, the bulk conductivity of La2−x Ba x Mo2O9−x/2 (x ≤0.18) decreases initially and then increases, a minimum value at La1.9Ba0.1Mo2O8.95 exists. Hebb–Wagner studies in argon atmosphere, which use an oxide-ion blocking electrode, show that La2−x Ba x Mo2O9−x/2 (x ≤0.18) are predominantly oxide-ion conducting in the temperature ranging from 773 to 1173K. The average thermal expansion coefficient of La1.84Ba0.16Mo2O8.92 determined by high-temperature XRD was deduced as great as 17.5×10−6 K−1 between 298 and 1173K. [Copyright &y& Elsevier]

Hexagonal CePO4 nanowires with a high aspect ratio were controllably synthesized through an oxalate-induced hydrothermal route. The hexagonal CePO4 and CePO4:Tb nanowires exhibited highly enhanced photoluminescence. The organic ligand oxalate was found to play a role for the oriented growth of the nanowires, as well as the structure evolution. The synthesis of nanostructured CePO4 with hexagonal and monoclinic structures was controlled by varying the molar ratios. A formation mechanism of the morphology and crystal structure was proposed. [Copyright &y& Elsevier]

The relationship between crystallographic orientation, microstructure characteristic and mechanical properties in 3.5Mn transformation induced plasticity (TRIP) steel that subjected to different cold rolling reduction and annealing time was elucidated. Before the hot-rolled plates were cold rolled to different thicknesses, large-fractioned Mn-enriched cementite particles dispersed in ferrite matrix were deliberately prepared to enhance Mn-partitioning and improve austenite stability. The evolution of microstructure was performed by electron probe micro-analyzer (EPMA), electron backscatter diffraction (EBSD), transmission electron microscopy (TEM) and X-ray diffraction (XRD), and the mechanical properties of the intercritical annealed samples were evaluated by uniaxial tensile test at room temperature. The results show that the cementite dissolution, ferrite recrystallization and austenite formation are strongly coupled and interdependent, resulting in a complex ultra-fine microstructure composed of retained austenite, ferrite and cementite in the intercritical annealed samples. Moreover, the Schmid factor (SF) distribution within the range of 0.25–0.5 was studied to understand its correlation with the crystallographic orientation and mechanical property of the test steel. It is concluded that the mechanical properties of 3.5Mn TRIP steel can be improved when the annealing period, orientation and austenite stability are optimized. [ABSTRACT FROM AUTHOR]

A series of 2-arylidene-N-(quinolin-6-yl)hydrazine-1-carboxamides 5a–5o were synthesized and characterized. The synthesized compounds (5a–5o) were screened in vitro against three breast cancer cell lines: SKBR3, MDA-MB-231, and MCF-7 cancer cell lines by the MTT assay. According to MTT results, compounds 5k and 5l showed better antiproliferative activities over MCF-7 cell lines with IC50 values of 8.50 and 12.51 μM. Colony formation assay indicated 5k/5l treatment obviously inhibited the growth of MCF-7 cells and 5k/5l-induced cell cycle was arrested in the G2-M phase. Moreover, 5k/5l significantly increased the level of cleaved PARP and induced the apoptosis in MCF-7 cells. In addition, compared to Hela cells, MCF-7 cells were more sensitive to 5k/5l treatment. [ABSTRACT FROM AUTHOR]

• The heterogeneity and interlocking effect were evaluated in SFP's stiffness and strength. • Strain related strength theory should be used for SFP in engineering. • The addition of fiber can restrain the trend of accelerated shear failure along interface. Semi-flexible pavement (SFP) material has been promoted to apply in pavement engineering mainly for its excellent performance in rutting resistance. But its mechanical behavior is complicated due to its heterogeneity and interlocking structure. According to the present study, the damage process of SFP (with and without fiber), as well as its porous asphalt (PA) matrix, under uniaxial compression test was detected employing acoustic emission (AE) technique. The heterogeneity and the interlocking effect were varied by changing the matrix porosity and the gradation, respectively. The stress-strain curves reveal that cement grouting could decrease the material's failure strain distinctly, while the addition of fiber made no effect on the results. Nevertheless, both the cement grouting and the addition of fiber caused medium and high amplitude (50–65 dB) AE signals during the AE detection. Besides, the Rise Angle (RA) value and energy distribution both illustrate that there was increasing trend in the amounts of shear cracking in SFP during compression, which was different from asphalt mixtures. And the addition of fiber could restrain the shear cracking to improve the crack resistance. Quantificationally, heterogeneity was characterized by standard deviation of compositions' modulus and an interlocking index was extracted from a modulus micromechanical model to characterize the interlocking effect. The Weibull distribution was adopted to characterize the damage evolution, where the cumulative AE energy was chosen as the damage variable. The result shows the two Weibull parameters m , n had obviously positive correlation with the matrix porosity and the interlocking index, respectively. [ABSTRACT FROM AUTHOR]

Abstract MicroRNA-520d-3p (miR-520d-3p) is a novel cancer-related miRNA and functions as a tumor suppressor in human cancers. However, the expression patterns and mechanisms of miR-520d-3p involved in hepatocellular carcinoma (HCC) remain rarely known. Here, we found that the expression levels of miR-520d-3p in HCC tissues and cells were significantly lower than in tumor-adjacent tissues and L02 cells. Decreased level of miR-520d-3p was relevant to poor overall survival, whereas miR-520d-3p up-regulation resulted in a marked inhibition of cell growth, migration and invasion. In addition, the long non-coding RNA, myocardial infarction associated transcript (MIAT) was up-regulated in both HCC tissues and cell lines. MIAT suppressed the expression and function of miR-520d-3p. Moreover, erythropoietin-producing hepatocellular A2 (EPHA2) was speculated and confirmed as a direct target of miR-520d-3p. We also demonstrated that MIAT may function as a sponge competitive endogenous RNA for miR-520d-3p, and thus regulate the molecular expression of EPHA2. In summary, our study has identified a novel signaling pathway through which miR-520d-3p exerts its anticarcinogenic roles and suggested that the MIAT/miR-520d-3p/EPHA2 may be a new target for HCC therapy. [ABSTRACT FROM AUTHOR]

The gas-phase selective oxidation of ethanol to acetaldehyde is a promising alternative to current Wacker process in which ethylene is catalyzed to acetaldehyde by palladium and copper chlorides in strong acidic solutions. The supported gold catalyst has been reported and showed excellent catalytic performance in gas-phase oxidation of ethanol. But its high price stimulates the studies to focus on non-noble-metal catalysts, or non-metal catalysts. Here, we report that nitrogen-doped carbon nanotubes as a bifunctional catalyst exhibits robust performance in the selective oxidation of ethanol to acetaldehyde. A stable catalytic performance with ethanol conversion of 72% and acetaldehyde selectivity of 90% at 270 °C was obtained. The substantial enhancement of acetaldehyde yield was ascribed to the synergistic effect of synchronously promoting the dissociative adsorption of O 2 and ethanol adsorption when incorporating graphite-like and pyridine-like nitrogen species. The kinetic analysis indicates that the introduction of nitrogen species can significantly decrease the activation energy of the reaction. The study of this bifunctional carbocatalyst may also provide guidance for the design of new carbon-based catalytic systems for the selective oxidation of alcohols via regulating the adsorption and activation ability of catalyst to reactants. [ABSTRACT FROM AUTHOR]

A novel ultra-high strength transformation induced plasticity (TRIP)-assisted steel with a better combination of ductility and stretch flangeability was fabricated by introducing a banded structure into the resulting microstructure. The corresponding relationships between microstructures and mechanical properties were studied in detail by the tensile test and the hole expansion test. These tests reveal that some pancake-like ferrite grains obtained in cold rolling are retained during intercritical annealing and finally form a banded structure together with martensite/austenite (M-A) islands along the rolling direction. The steel can be further strengthened in the subsequent punching process, while uniformly-distributed bainite matrix with fine M-A islands dominates the overall microstructure after annealing at higher annealing temperatures. The banded structure of the soft ferrite phase will promote crack propagation along the rolling direction rather than in the thickness direction, thereby favoring improvement of the hole expansion ratio (HER). Instead, the mixed bainite-M-A islands microstructure led to increased micro-voids density at the edge of the shear affected zone (SAZ) after the hole punching process and a great number of cracks rapidly propagated through the thickness direction in the matrix, which is responsible for a decrease in HER. Excellent mechanical properties were obtained in the low-temperature annealed sample with an HER of 29–35%, elongation of 21–26%, tensile strength of 941–1016 MPa, and yield strength of 426–566 MPa. [ABSTRACT FROM AUTHOR]

Abstract: A method is developed for the determination of trace mercury in biological samples using photo chemical vapor generation (PVG) and isotope dilution inductively coupled plasma mass spectrometry (ID ICPMS) detection. Biological tissues were solubilized in formic acid. Subsequently, the sample solutions were exposed to an ultraviolet (UV) source for the reduction of mercury into vapor species prior to ICPMS measurements. The formic acid served not only as a tissue solubilizer in the sample preparation procedure, but also as a photochemical reductant for mercury in the PVG process. The problem arising from the opaque formic acid digested solution was efficiently solved by using ID method. The optimum conditions for sample treatment and PVG were investigated. A limit of detection (LOD) of 0.5pgg-1, based on an external calibration, provided 350-fold improvement over that obtained by utilizing conventional pneumatic nebulization sample introduction. Method validation was demonstrated by the determination of total mercury in several biological tissue certified reference materials (CRMs). The results were in good agreement with the certified values. [Copyright &y& Elsevier]

The tetragonal TbPO was controlled synthesized via a simple solvothermal route by using glycol as solvent. The structures and micromorphologies of the as-synthesized TbPO have been investigated by means of X-ray powder diffraction (XRD) and field-emission scanning electronic microscopy (FE-SEM). The results showed that the tetragonal TbPO are composed of square-like particles about 200 nm in diameter. The photoluminescence spectra exhibited that the emission spectra of the sample could be divided into two parts, representing the D → F (J = 6, 5, 4, 3) transitions and D → F (J = 6, 5, 4, 3) transitions of Tb. [ABSTRACT FROM AUTHOR]

• The impact of mucoid phenotype for A. baumannii was evaluated. • The mucoid A. baumannii isolates were more hypervirulent than nonmucoid strains. • The prevalence of multi-resistant A. baumannii strains in Anhui may be ST2 clone. • No biofilm formation ability was observed for mucoid A. baumannii. • Several genes were associated with virulence regulation of mucoid A. baumannii. Mucoid phenotype is an important adaptive defense response for Acinetobacter baumannii (A. baumannii). The aim of this study was to analyze the impact of mucoid phenotype for the molecular characteristics and virulence of A. baumannii. We observed that the colonies of mucoid A. baumannii were moist, with an elevated surface, and the wire drawing result was positive. Transmission electron microscopy data showed that the outer wall of the mucoid colonies was not smooth, had protruding pseudopodia, and was surrounded by a layer of unknown material. Antibiotic susceptibility testing showed that the mucoid strains were multidrug resistant. Notably, the mucoid phenotype and antibiotic resistance were not correlated with the amount of biofilm produced by A. baumannii. MLST data demonstrated that the mucoid A. baumannii strains belonged to type ST2. Most (82.6 %, 38/46) of the multidrug-resistant nonmucoid strains also belonged to the molecular type ST2 and to other types, including ST129, ST158, ST195, ST80 and ST3. Moreover, mucoid A. baumannii strains were more virulent than nonmucoid isolates in a mouse model. The comparative transcriptomic data indicated that 15 genes, especially IX87_RS16955 (acnA), IX87_RS10800 (XanP), IX87_RS12875 (GlmM), IX87_RS00885 and IX87_RS12395 (bfr), were possibly associated with the phenotype and virulence of mucoid A. baumannii. In conclusions, the study comprehensively describes the molecular characteristics and virulence regulatory mechanism of mucoid A. baumannii, and provides novel insights for the prevention and treatment of infections associated with these strains. [ABSTRACT FROM AUTHOR]

The widespread nature of several viruses is greatly credited to their rapidly altering RNA genomes that enable the infection to persist despite challenges presented by host cells. Within the RNA genome of infections is RNA-dependent RNA polymerase (RdRp), which is an essential enzyme that helps in RNA synthesis by catalysing the RNA template-dependent development of phosphodiester bonds. Therefore, RdRp is an important therapeutic target in RNA virus-caused diseases, including SARS-CoV-2. In this review, we describe the promising RdRp inhibitors that have been launched or are currently in clinical studies for the treatment of RNA virus infections. Structurally, nucleoside inhibitors (NIs) bind to the RdRp protein at the enzyme active site, and nonnucleoside inhibitors (NNIs) bind to the RdRp protein at allosteric sites. By reviewing these inhibitors, more precise guidelines for the development of more promising anti-RNA virus drugs should be set, and due to the current health emergency, they will eventually be used for COVID-19 treatment. Image 1 • This article provides an overview of RdRp inhibitors that have been launched or are in clinical studies for the treatment of RNA virus infections, including COVID-19. • Nucleoside inhibitors (NIs) exhibit broad-spectrum antiviral activity but pose a more serious toxicity risk than non-nucleoside inhibitors (NNIs) because high dosages of NIs result in accumulation in plasma. • Structurally diverse NNIs are endowed with high potential activities but tend to induce drug resistance due to the RdRp allosteric site. [ABSTRACT FROM AUTHOR]

• Effective coarse aggregate-grouting cement contacts were distinguished from non-effective ones. • A fast contact calculation method was proposed. • A good linear relationship was found between the mechanical and morphological interlocking indexes. Semi-flexible pavement (SFP) material has been proven to have more interlocking effect than its Porous Asphalt (PA) matrix because of the secondary skeleton consisting of interconnected grouting cement. However, because of the irregular, elongated and concave shapes conflicting with the requirement of aggregates, together with a stiffness much higher than that of asphalt binder (which can bear and transfer most of the load), it is hard to define whether cement grouted into air voids works mainly as a role of another aggregate or binder. Based on the X-ray computed tomography and digital image process method, this study aims to distinguish effective coarse aggregate-grouting cement contacts (cement working as aggregates) from noneffective ones (cement working only as binder). A contact classification method, as well as a fast contact calculation method, was proposed. The characteristics of different types of contacts were analyzed and two morphological interlocking indexes were established based on the concept of contact points and contact lines, respectively. A mechanical interlocking index was also back-calculated from a micromechanical model as a reference. The result reveals that there exists a good linear relationship between the mechanical and morphological interlocking indexes, verifying the validity of the contact classification method. Additionally, with a larger quantity than that of contacts between coarse aggregates, only one-sixth of aggregate-cement contacts are effective ones, the number of which is half of the coarse aggregates' contacts. As for contact lines, while the average length of effective aggregate-cement contacts is the same as that of aggregate contacts, the length of the noneffective ones is only the half. [ABSTRACT FROM AUTHOR]