Search

This paper presents an elastoplastic model to estimate the hydromechanical behavior of unsaturated soils based on state boundary hypersurface. Through mechanical hypersurface, the influence of saturation on yield stress can be expressed in a full form rather than an incremental form. Two hydraulic hypersurfaces and one mechanical hypersurface are proposed to establish the model. Two hydraulic hypersurfaces, composed of degree of saturation, void ratio and matrix suction, define the plastic hydraulic boundary. The elastic hydraulic behavior of unsaturated soils can be represented by scanning lines between these two hydraulic hypersurfaces. The mechanical hypersurface, composed of degree of saturation, void ratio and effective stress, defines the plastic mechanical boundary. The elastic mechanical behavior of unsaturated soils can be represented by scanning lines below the mechanical hypersurfaces. A large number of laboratory tests are used to validated the proposed model, showing that it can reasonably capture important features of the hydromechanical behavior of unsaturated soils. [ABSTRACT FROM AUTHOR]

During the construction of supramolecular polymers of smaller nanoparticles/nanoclusters bearing hierarchy and homochirality, the mechanism understanding via intuitive visualization and precise cross-scale chirality modulation is still challenging. For this goal, a cooperative self-assembly strategy is here proposed by using ionic complexes with uniform chemical composition comprising polyanionic nanocluster cores and surrounded chiral cationic organic components as monomers for supramolecular polymerization. The single helical polymer chains bearing a core-shell structure at utmost length over 20 μm are demonstrated showing comparable flexibility resembling covalent polymers. A nucleation-elongation growth mechanism that is not dealt with in nanoparticle systems is confirmed to be accompanied by strict chiral self-sorting. A permeable membrane prepared by simple suction of such supramolecular polymers displays high enantioselectivity (e.e. 98% after four runs) for separating histidine derivatives, which discloses a benefiting helical chain structure-induced functionalization for macroscopic supramolecular materials in highly efficient racemate separation. Understanding the mechanism for supramolecular polymer assembly from nanoclusters bearing hierarchy and homochirality is challenging. Here, the authors report a cooperative self-assembly strategy using ionic complexes with chiral surfactants through a nucleation-elongation growth mechanism with chiral self-sorting and prepare a permeable membrane for the separation of histidine derivatives. [ABSTRACT FROM AUTHOR]

Emerging adulthood is a pivotal period for romantic relationships, yet the specific mechanisms through which attachment anxiety influences relationship dynamics and psychological outcomes in this phase are poorly understood. Particularly, in the context of romantic dyads, understanding how partners' behaviors and emotional patterns reciprocally influence each other remains underexplored. This study utilizes the Actor-Partner Interdependence Model and Actor-Partner Interdependence Mediator Model to explore the relationship between attachment anxiety,relational aggression (both perpetration and victimization), and depressive symptoms among emerging adults. A sample of 138 mixed-sex emerging adulthood couples from China, was recruited (Mage = 21.40, SD = 2.54; 50% female, 62.6% reporting that this relationship was ongoing for more than a year). Attachment anxiety significantly predicted relational aggression in both partners, with male attachment anxiety also significantly predicted female relational aggression. Significant indirect effects of both partners' relational aggression perpetration and victimization on their own and each other's relationship between attachment anxiety and depressive symptoms. These findings contribute to understanding the intricate dynamics of attachment anxiety and relational aggression in romantic relationships during emerging adulthood, emphasizing the need for targeted interventions to mitigate these risks. [ABSTRACT FROM AUTHOR]

Highlights: This review systematically compares the different effects of O2-type and O3-type structures on voltage decay for Li-rich layered oxide (LRLO) cathode. The development of O2-type materials and the corresponding mechanisms for addressing voltage decay are comprehensively reviewed. The perspectives and challenges for designing high-performance O2-type LRLO cathodes without voltage decay are proposed. Li-rich layered oxide (LRLO) cathodes have been regarded as promising candidates for next-generation Li-ion batteries due to their exceptionally high energy density, which combines cationic and anionic redox activities. However, continuous voltage decay during cycling remains the primary obstacle for practical applications, which has yet to be fundamentally addressed. It is widely acknowledged that voltage decay originates from the irreversible migration of transition metal ions, which usually further exacerbates structural evolution and aggravates the irreversible oxygen redox reactions. Recently, constructing O2-type structure has been considered one of the most promising approaches for inhibiting voltage decay. In this review, the relationship between voltage decay and structural evolution is systematically elucidated. Strategies to suppress voltage decay are systematically summarized. Additionally, the design of O2-type structure and the corresponding mechanism of suppressing voltage decay are comprehensively discussed. Unfortunately, the reported O2-type LRLO cathodes still exhibit partially disordered structure with extended cycles. Herein, the factors that may cause the irreversible transition metal migrations in O2-type LRLO materials are also explored, while the perspectives and challenges for designing high-performance O2-type LRLO cathodes without voltage decay are proposed. [ABSTRACT FROM AUTHOR]

Introduction: Adrenal hemorrhage (AH) is a rare condition and severe cases can lead to acute adrenal insufficiency with potentially life-threatening consequences. AH can be caused by a variety of etiologic factors, including systemic lupus erythematosus and antiphospholipid syndrome (APS). The early identification and treatment of these patients improves their prognosis. Objective: The aims of this study were to analyze and summarize the clinical characteristics of systemic lupus erythematosus patients with AH. Methods: The clinical characteristics of 6 systemic lupus erythematosus patients complicated with AH admitted to Peking Union Medical College Hospital and Beijing Shijitan Hospital from May 2004 to April 2022 were retrospectively analyzed. Results: The diagnosis of AH was based on computed tomography (CT) findings. Two patients had bilateral lesions, and the other 4 patients had unilateral lesions. The symptoms of adrenal insufficiency were observed in 2 patients. The frequent presenting symptoms were abdominal pain, lower abdominal distension, vomiting, weakness, fever, arthrodynia, and skin rash. Four patients had APS. Five patients (4 patients with APS and 1 patient without APS) had thromboembolic events. All patients received glucocorticoid and immunosuppressant therapy. Five patients were treated with anticoagulant therapy. Follow-up imaging examinations showed a partial or total regression of the lesions after treatment. Conclusions: In the proper clinical setting, having high clinical suspicion for AH, early diagnosis and timely management is crucial to avoid life-threatening adrenal insufficiency. Key Points • AH is a rare condition and severe cases may lead to death. It can be caused by a variety of etiologic factors, including SLE. • In patients with SLE, especially combined with APS, if they complain of abdominal pain, particularly when common gastrointestinal involvement is difficult to explain, a high index of clinical suspicion is needed for the diagnosis of AH. • Early identification of AH in SLE patients can improve their prognosis. [ABSTRACT FROM AUTHOR]

Tunnel seismic advance prediction can effectively reduce the construction risk during tunnel excavation. Compared with the 2-D method, the 3-D method is more conducive to describing the spatial characteristics of the geological body by adding the seismic data in the vertical direction. However, some drawbacks still need improvement in the current 3-D tunnel seismic prediction method. (1) The geometry is complex, which is destructiveness, high cost, and time-consuming, and will delay the tunnel construction schedule. (2) Illumination of the anomalous body is insufficient, and the precision of migration imaging is low. (3) Shot points are far away from the tunnel face, the energy loss at the shot points is more serious. (4) The received signals at the tunnel wall have the surface wave with strong energy when the shot points are placed on the tunnel wall. (5) The geometry is not linear, so the directional filtering method cannot be used to extract the reflection wave. To overcome the drawbacks of the current prediction method, a new 3-D symmetrical tunnel seismic prediction method is proposed. Six geophones are installed on the tunnel wall, two on the left side, two on the right side, and two on the top side. Twenty-four shot points are placed on the tunnel face and near both sides of the tunnel wall, twelve shot points on the left side and twelve shot points on the right side. The shot points will move along with the forward excavation of the tunnel. The wavefield analysis, illumination statistics, and 3-D reverse time migration imaging are used to evaluate the proposed method. The result of modeled data indicates that the proposed 3-D geometry has some advantages: (1) the geometry is simple and the geophone installation time is short; (2) it has high illumination energy, wide illumination range, and can improve the prediction distance and imaging accuracy; (3) the proposed 3-D method can better estimate the velocity of surrounding rock and is more conducive to extracting the reflection wave with high resolution. [ABSTRACT FROM AUTHOR]

Despite extensive research on the psychological impacts of digital technology, the nuanced dynamics between adolescent loneliness and problematic smartphone use, particularly across different educational levels and genders, remain underexplored. This study aims to fill this gap by employing a Random Intercept Cross-Lagged Panel Model to dissect the bidirectional relationship between loneliness and problematic smartphone use among adolescents, with a focus on the moderating roles of educational levels and gender. Engaging 3132 students from various educational institutions in China, the research conducted a three-wave longitudinal analysis across 2022–2023. The final number of participants included 1120 adolescents (53.5% female; age in 2022: M = 14.57 years, SD = 1.57). Results reveal that loneliness significantly predicts problematic smartphone use, but not vice versa, highlighting a unidirectional influence. The study uncovers crucial differences across educational levels and gender, emphasizing the stronger effect of loneliness on problematic smartphone use among junior high students and female adolescents. These findings underscore the complexity of adolescent loneliness and its relationship with digital behavior, suggesting a need for tailored interventions considering both gender and developmental stages. [ABSTRACT FROM AUTHOR]

Objective: The original 24-item School Refusal Assessment Scale-Revised (SRAS-R) assesses four functions/conditions regarding school refusal behavior (SRB), bridging assessments, and treatments of SRB. No validated Chinese versions are available. Methods: To validate the Chinese version of the SRAS-R, an anonymous cross-sectional survey was conducted from February to March 2022 among 1108 secondary school students in Taizhou, China. Results: Confirmatory factor analysis (CFA) did not support the original 4-factor model. Three items were thus removed in the exploratory factor analysis performed in the first half-spilt subsample, yielding a 5-factor model which was confirmed by CFA in the second subsample. The resulting 21-item scale/subscales of the Chinese SRAS-R generally demonstrated measurement invariance across sex and student types and satisfactory internal consistency, absence of ceiling effect and floor effect, and concurrent validity with the two external variables of preference of not going to school and depressive symptoms. Significant sex and student type differences in subscale scores were found. Conclusions: The 21-item and 5-factor Chinese version of the SRAS-R showed satisfactory psychometric properties and can be applied to research on SRB among Chinese adolescents. Future studies should validate it in other countries. [ABSTRACT FROM AUTHOR]

Problematic smartphone use (PSU) is a prevalent behavioral problem in young people. Notably, levels of PSU positively correlate with levels of social anxiety. However, the mechanism underlying the relationship between social anxiety and PSU has not been fully elucidated. Coping style and friend support are potential factors involved in such a mechanism. In this study, we collected a battery of surveys in a group of college students (n = 512). Then, we used the Interaction of Person-Affect-Cognition-Execution (I-PACE) model to examine the possible mediating role of coping style in the relationship between social anxiety and PSU, and further tested the possible moderating role of perceived friend support. We built a structural equation model and found a positive relationship between social anxiety and PSU, as well as finding that coping style partially mediated said relationship. Further, perceived friend support moderated the association between social anxiety and coping style. This relationship became stronger for college students with higher levels of friend support. Our findings are important in understanding why individuals with social anxiety are prone to PSU, and why individuals with better friend support are resistant to such behavior. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the longitudinal and reciprocal relationships among problematic smartphone use (PSU), depressive symptoms (DS), and suicidal ideation (SI) in Chinese university students. Using a cross-lagged design, the Mobile Phone Addiction Inventory Scale, the Center for Epidemiologic Studies Depression Scale, and the Self-Rating Idea of Suicide Scale as research instruments, 194 university students completed a questionnaire four consecutive times. June of Year 1, December of Year 2, June of Year 2, and December of Year 3 of their college study. We refer to these as the Time 1 (T1), Time 2 (T2), Time 3 (T3), and Time 4 (T4) assessments, respectively. The levels of PSU and DS fluctuated significantly over time. DS at T1 was significantly predicted to influence SI at T2 (β = 0.17, p <.05); DS at T3 was significantly predicted by PSU and by SI at T2 (respectively, β = 0.30, p <.05; β = 0.21, p <.05); DS at T2 significantly predicted PSU at T3 (β = 0.14, p <.05); and DS at T3 significantly predicted SI at T4 (β = 0.14, p <.05) in the cross-lagged pathway. DS at T3 fully mediated the relationship between PSU at T2 and SI at T4 (indirect effect: β = 0.133, 95% CI = [0.063, 0.213]). The results suggest that there is a reciprocal relationship between PSU and DS and, furthermore, that DS plays an important mediating role between PSU and SI. Our results suggest the importance of early identification and treatment of SI. Timely reduction of PSU and improvement of DS among university students may help prevent SI. [ABSTRACT FROM AUTHOR]

Currently, the common way for structural investigation is to confirm the amorphous state of the quenched slag by XRD prior to Raman analysis. However, if the slag precipitates a few nanocrystals during quenching, XRD may not recognize them, but the slag structure has been changed. Therefore, this paper proposes to combine TEM with XRD and Raman for analyzing the slag structure and to verify it with blast furnace slag obtained by different quenching methods. The results show that the XRD curves of the slags obtained by quenching in water or on a stainless steel plate show amorphous states, but the deconvolution results of Raman spectra are significantly different. The TEM analysis finds a few crystals in the slag obtained by the latter, which is responsible for the structural differences. Therefore, it is necessary to confirm the amorphous state of the slag by both XRD and TEM before studying the structure. [ABSTRACT FROM AUTHOR]

Coal measure strata are composed of many kinds of rock layers with different properties, and the energy accumulation ability of each rock layer is different, which causes the uneven distribution of energy. In order to explore the accumulation layer of rock burst energy in coal–rock system, based on the structural characteristics and mechanical properties of coal and rock, the mechanical model of coal–rock combined body was constructed, and the calculation formula of energy distribution of coal–rock combined body was deduced. The axial compression tests of coal–rock combined body under five confining pressures (0, 5, 10, 15 and 20 MPa) were designed and carried out. The results show that: 1) Under five confining pressures, the average compressive strength of the specimens was 18.74 MPa, 20.75 MPa, 24.68 MPa, 28.02 MPa and 32.05 MPa, respectively. With the increase in confining pressure, the compressive strength also increased linearly; 2) Under the five confining pressures, the pre-peak accumulated energy of the specimens was 0.106 kJ, 0.244 kJ, 0.591 kJ, 0.758 kJ and 1.602 kJ. With the continuous increase in the confining pressure, the pre-peak accumulated energy increased exponentially; 3) With the increase in confining pressure, the coal component accumulation energy increased exponentially, followed by 0.069 kJ, 0.182 kJ, 0.440 kJ, 0.630 kJ and 1.419 kJ, and the proportion of coal component accumulation energy was 65.14%, 71.63%, 76.72%, 82.89% and 87.07%, respectively, which were all greater than 50%. Combined bodies accumulated more energy under loading conditions, most of which were accumulated on coal components, and coal components were the main carriers of energy accumulation, which played a leading role in the destruction of combined bodies; 4) The energy distribution test method was discussed and analyzed. The energy distribution test method of coal–rock combined body based on single specimen method could effectively avoid the influence of size effect and coal–rock individual difference on energy accumulation. At the same time, the test time was shortened, the test workload was reduced, and the calculation accuracy was improved; 5) The rationality and reliability of the two methods for direct and indirect determination of coal–rock component energy were demonstrated. The error rates of the two methods were 2.936%, 1.846%, 3.125%, 3.412% and 0.862%, which were less than 5%. The error had little effect on the test results. The research results have reference significance for exploring the key strata of rock burst energy accumulation and the precise prevention and control of rock burst. [ABSTRACT FROM AUTHOR]

In our previous work, a recombinant aflatoxin-degrading enzyme derived from Myxococcus fulvus (MADE) was reported. However, the low thermal stability of the enzyme had limitations for its use in industrial applications. In this study, we obtained an improved variant of recombinant MADE (rMADE) with enhanced thermostability and catalytic activity using error-prone PCR. Firstly, we constructed a mutant library containing over 5000 individual mutants. Three mutants with T50 values higher than the wild-type rMADE by 16.5 °C (rMADE-1124), 6.5 °C (rMADE-1795), and 9.8 °C (rMADE-2848) were screened by a high-throughput screening method. Additionally, the catalytic activity of rMADE-1795 and rMADE-2848 was improved by 81.5% and 67.7%, respectively, compared to the wild-type. Moreover, structural analysis revealed that replacement of acidic amino acids with basic amino acids by a mutation (D114H) in rMADE-2848 increased the polar interactions with surrounding residues and resulted in a threefold increase in the t1/2 value of the enzyme and made it more thermaltolerate. Key Points: • Mutant libraries construction of a new aflatoxins degrading enzyme by error-prone PCR. • D114H/N295D mutant improved enzyme activity and thermostability. • The first reported enhanced thermostability of aflatoxins degrading enzyme better for its application. [ABSTRACT FROM AUTHOR]

The presence of water in sandstone joints affects the shear characteristics of the joints, which is of considerable importance to the stability evaluations of rock slopes or tunnels subjected to water fluctuations. A series of direct shear tests with three immersion durations (30, 180, and 360 d) in water were conducted on the sandstone joint specimens collected from the reservoir area of the Three Gorges hydropower station, China. To perform duplicate tests, three-dimensional (3D) optical scanning and 3D rigid engraving were coupled to produce sandstone joints with the same surface morphology. The shear curves of the dry and immersed sandstone joints were divided into the three stages of sliding, shear-breaking, and post-peak wearing. The damaged area of the immersed joints decreased with the increased immersion duration under the same normal loading. The immersion duration did not affect the shear mode of the joints, and the peak and residual shear strengths of the sandstone joints decreased by approximately 10–28% and 2.9–26.4%, respectively, after the 360-d immersion. Experimental results pointed to the lubricant effect as the dominant mechanism for a water-induced reduction in the shear strength of the joints, followed by the chemical dissolution effect. Given the lubricant and chemical dissolution effects, a semi-empirical shear strength criterion was proposed to predict the peak shear strength of the rock joints subjected to the immersion durations. Validation against experimental shear data obtained in this study and from related literature indicated satisfactory accuracy of the proposed criterion for predicting the peak shear strength after the immersion. An engineering example of the Jianchuandong unstable rock mass located in the Three Gorges reservoir was used to demonstrate the function of wetting in lowering its safety factor. Highlights: 3D scanning and 3D engraving were coupled to produce sandstone joints. Direct shear tests with different immersion durations were conducted on joints. A novel shear strength criterion was developed considering immersion duration. [ABSTRACT FROM AUTHOR]

In geotechnical engineering, jointed rock mass is often affected by water-rock interaction and confining pressure effect. Axial compression tests were carried out on intermittent jointed sandstones with different inclinations under different immersion times and different confining pressures. The results show that (1) with the increase of immersion time, the compressive strength and elastic modulus gradually decreases. With the increase of the confining pressure, the compressive strength and the amplitude also increases. With the increase of the joint inclination, the compressive strength and elastic modulus changes in a “V-shaped” shape, and the compressive strength and elastic modulus are the smallest when the joint inclination is 60°. (2) With the increase of immersion time, the number of secondary cracks increases, and the angle between the crack and the radial direction of the sample is about 0~45°, which belongs to plastic failure. (3) With the increase of the confining pressure, the cracks become shorter and the number increases, the angle between the crack and the radial direction of the sample becomes smaller. The plastic failure gradually occurs in the sample. (4) The deterioration of the mechanical properties of the intermittent jointed sandstone is essentially the external manifestation of the physical and chemical action of the sample under the water-rock action and the effect of confining pressure, and it is a process of continuous accumulation of damage. [ABSTRACT FROM AUTHOR]

Synthetic framework materials have been cherished as appealing candidates for separation membranes in daily life and industry, while the challenges still remain in precise control of aperture distribution and separation threshold, mild processing methods, and extensive application aspects. Here, we show a two-dimensional (2D) processible supramolecular framework (SF) by integrating directional organic host-guest motifs and inorganic functional polyanionic clusters. The thickness and flexibility of the obtained 2D SFs are tuned by the solvent modulation to the interlayer interactions, and the optimized SFs with limited layers but micron-sized areas are used to fabricate the sustainable membranes. The uniform nanopores allow the membrane composed of layered SF to exhibit strict size retention for substrates with the rejection value of 3.8 nm, and the separation accuracy within 5 kDa for proteins. Furthermore, the membrane performs high charge selectivity for charged organics, nanoparticles, and proteins, due to the insertion of polyanionic clusters in the framework skeletons. This work displays the extensional separation potentials of self-assembled framework membranes comprising of small-molecules and provides a platform for the preparation of multifunctional framework materials due to the conveniently ionic exchange of the counterions of the polyanionic clusters. Synthetic framework materials are appealing candidates for the fabrication of separation membranes but realizing precise control of aperture distribution and separation threshold remains challenging. Here, the authors show a two-dimensional processible supramolecular framework which can be used in the fabrication of separation membranes by integrating directional organic host-guest motifs and inorganic functional polyanionic clusters. [ABSTRACT FROM AUTHOR]

This paper presents three-dimensional numerical simulations with the established realizable k−ε model to clarify the underlying and interacting mechanisms between the film cooling and the internal cooling. On the one hand, the effects of three different internal cooling channels, i.e., smooth channel, continuous ribbed channel, and truncated ribbed channel, on the film cooling effectiveness and the discharge coefficients are investigated. On the other hand, the influences of three different film cooling holes, i.e., cylindrical hole, two elliptical holes and two circular-to-elliptical holes, on the heat transfer performances and pressure loss of the internal cooling channel are revealed. Especially, the suction effects of the film cooling holes are analyzed through setting up baselines with only internal cooling channels. Results show that the placement of ribs in the internal channel has different influences on the film cooling effectiveness with respect to different hole shapes depending on the blowing ratio. The discharge coefficient of the film hole can be improved by introducing ribs to the internal channel. Suction of film hole is helpful for enhancing the heat transfer performance and reducing the pressure loss of the internal channel. Besides, ribs instead of the suction effect of film hole play a major role to enhance the heat transfer performance in the internal cooling channel. [ABSTRACT FROM AUTHOR]

Existing hyperspectral remote sensing image classification methods have separate feature extraction and classifiers. At the same time, separate training will increase network complexity and be very time-consuming. Therefore, a deep learning space-spectrum combined with hyperspectral remote sensing image classification algorithm is proposed. First, mathematical transformation is used to stabilize the growth rate of remote sensing image radiation value, and reduce the standard deviation of spatial distribution characteristics of GIS information DN value, so as to increase the growth rate of remote sensing spectral radiation value in suburban areas. Then, a band combination strategy LSTM algorithm that focuses on global features is selected to regroup the bands of the spectral vector of each pixel of the hyperspectral data, which can effectively extract the context features between adjacent spectra. Finally, principal component analysis is performed on the satellite remote sensing image, and retain the first few principal components to achieve dimensionality reduction; the multiscale convolutional neural network is applied to extract the spatial features of the satellite remote sensing image after dimensionality reduction. The end-to-end structure is used to extract spectral features and spatial features simultaneously to realize satellite remote sensing image analysis. The simulation experiment proves that the calculation accuracy of the urban pattern change trend of the algorithm in this paper is high, and the calculation results are more convergent, which can provide more accurate trends of the urban pattern change and play a guiding role in the future construction of the city. [ABSTRACT FROM AUTHOR]

In this paper we prove the tail variational principle for actions of countable amenable groups. This allows us to extend some characterizations of asymptotic h-expansiveness from ℤ-actions to actions of countable amenable groups. [ABSTRACT FROM AUTHOR]

Recent research has identified a relationship between online gaming addiction (OGA) and depressive symptoms. However, little is known regarding the underlying mechanisms. The present study aims to test the moderating effect of flow experience in the association between OGA and depressive symptoms via affect balance. A total of 1050 game players of the Glory of the King completed measures of online gaming addiction, depressive symptoms, affect balance, and flow experience. Results showed that OGA was positively associated with depressive symptoms, and affect balance mediated that association. Flow experience exacerbated the negative relationships between OGA and affect balance while tempered the positive impact of affect balance on depressive symptoms. This study contributes to a better understanding of how OGA increases the risk of depressive symptoms, and reveals the dark side of flow experience among online game players. The importance of enhancing affect balance and reducing flow experience in preventing depressive symptoms is highlighted. [ABSTRACT FROM AUTHOR]

To study the mechanism and evolution process of water inrush geohazards under the complex geological environment of the karst cave-fractured zone, a large-scale physical three-dimensional (3D) model test was first performed. Then the conceptual model for the evolution process of water inrush geohazards and the simplified theoretical model for the critical hydraulic pressure were both established based on the main characteristics of the water inrush geohazard in the engineering background and that in the model test. A new method was developed for modeling the geological environment of the karst cave-structural plane, and two formulae describing the critical water pressure of water inrush geohazards under two failure models of tensile-shear fracture failure and compression-shear fracture failure were also deduced based on fracture mechanics. The results showed that: (1) the evolution process of the water inrush geohazard can be divided into four stages, which include the initial balance, the propagation of original cracks, the formation of the dominant water inrush channel, and the instability of the waterproof rock mass; (2) the suddenness of water inrush geohazards becomes stronger with the increase of the hydraulic pressure; (3) the calculated critical hydraulic pressure of water inrush geohazards is similar to the measured critical hydraulic pressure in the model test, which validated the accuracies of the theoretical model, and the failure model of water inrush geohazards in this research is compression-shear fracture failure. [ABSTRACT FROM AUTHOR]

In water-rich mines, water conservancy, and hydropower projects, the rock mass is immersed in water for a long time, which leads to changes in its mechanical properties and affects the safety and stability of the engineering rock mass. Based on the long-term immersion of rock mass with intermittent joints by water, uniaxial compression tests were carried out on prefabricated intermittent jointed sandstone with five inclinations (0°, 30°, 45°, 60°, 90°) and three connectivity ratios (0.25, 0.50, 0.75) under different immersion times to study sandstone with intermittent joints' mechanical response and deterioration mechanism. The research shows that: (1) With the increase of the joint inclination, the compressive strength and elastic modulus of the sandstone with intermittent joints first decreased and then increased, showing a U-shaped distribution. The compressive strength and elasticity of the sample with an inclination of 60° reach the minimum value; at the initial stage of immersion, the deterioration effect of the sample is more significant, and the deterioration effect decreases gradually with the increase in immersion time; in the initial stage of water immersion, the deterioration effect of the sample is more significant, and with the increase of the immersion time, the deterioration effect gradually weakens. (2) Immersion time and joint inclination have a great influence on the included angle, number, and mode of failure cracks. With the increase in immersion time, the plastic characteristics of the sample increase obviously, showing the characteristics of loose and weak; with the increase in joint inclination, the failure mode of the sample gradually changes from tension failure to tension shear failure, and tension failure. The influence degree of joints on failure is weak-induction-control-induction. (3) Under the water–rock action, the cement between mineral particles of the sample is gradually dissolved, the cementation of mineral particles is weakened, and the mineral particles develop into layered and flake structure, which gradually evolves from dense structure to porous loose structure. (4) The deterioration mechanism of the mechanical properties of the sandstone with intermittent joints under the water–rock action was analyzed from the perspectives of physics, chemistry, and mechanics. The deterioration of the mechanical properties of the sample is a process of gradual accumulation of damage. [ABSTRACT FROM AUTHOR]

In the present work, a new type of pH-responsive drug delivery system was successfully designed that is based on Fe3O4 magnetic nanoparticles functionalized with cucurbit[6]uril by thiol-ene click reaction. Various characterization experiments, such as SEM, TEM, FT-IR, XRD, XPS, and VSM, were performed to research the microstructure, morphology, composition, and physicochemical property of the prepared materials in detail. Then, the prepared cucurbit[6]uril-functionalized Fe3O4 magnetic nanoparticles were used to research the loading efficiency, loading capacity, and release percentage of doxorubicin. In the meantime, the influence of sample volume, loading time, pH, temperature, sample concentration, and carrier dosage on the loading efficiency was assessed and in vitro drug release behavior of doxorubicin in phosphate buffer solution with different pH values (3.0, 5.5, and 7.4) was examined. The results demonstrated that the developed drug delivery system based on cucurbit[6]uril-functionalized Fe3O4 magnetic nanoparticles showed high loading efficiency and pH-responsive controlled release behavior. [ABSTRACT FROM AUTHOR]

ZrC and ZrB2 are both typical ultra-high temperature ceramics, which can be used in the hyperthermal environment. In this study, a method for preparing ultrafine ZrC-ZrB2 composite powder was provided, by using the raw materials of nano ZrO2, carbon black, B4C, and metallic Ca. It is worth pointing out that ZrC-ZrB2 composite powder with any proportion of ZrC to ZrB2 could be synthesized by this method. Firstly, a mixture of ZrC and C was prepared by carbothermal reduction of ZrO2. By adjusting the addition amount of B4C, ZrC was boronized by B4C to generate ZrC-ZrB2 composite powder with different compositions. Using this method, five composite powders with different molar ratios of ZrC and ZrB2 (100ZrC, 75ZrC-25ZrB2, 50ZrC-50ZrB2, 25ZrC-75ZrB2, and 100ZrB2) were prepared. When the temperature of boronization and decarburization process was 1473 K, the particle size of product was only tens of nanometres. Finally, the oxidation characteristics of different composite powders were investigated through oxidation experiments. The oxidation resistance of ZrC-ZrB2 composite powder continued to increase as the content of ZrB2 increased. [ABSTRACT FROM AUTHOR]

After the coal mine disaster, the collapsed accumulation body blocked the roadway and interrupted the rescue route, which seriously affected the development of rescue. Based on the post-disaster blockage rescue route of the collapsed accumulation body, the morphology and structural characteristics of the accumulation body were analyzed, and the process of excavating the rescue channel in the collapsed accumulation body in the mining roadway was simulated using CDEM software, and the moving mode of accumulation body fragments was discussed. The study found that: the formation of the accumulation body is the process of continuous "self-organization" adjustment of the rock fragments; the accumulation body along the direction of the roadway axis is divided into three areas: pre-sorting accumulation area, post-sorting accumulation area, and non-sorting accumulation area; the particle size of the accumulation body-particle content conforms to the normal distribution; the harder the rock fragments constituting the accumulation body is, the particle size of the fragments is more different; the number of contact points of the fragments of the tightly accumulation body is more than that of the loose accumulation body; the excavation of the rescue channel is accompanied by the random "self-organization" movement of the accumulated body; the settlement and deformation of the accumulated body is actually the continuous collapse of the old arch structure, and the process of continuous formation of a new arch structure; the initial force of the rescue channel excavation is small, then it increases sharply, and finally stabilizes; the fragment adjustment forms are mainly divided into horizontal movement adjustment, vertical movement adjustment, rotation movement adjustment, and multi-directional movement adjustment. The research conclusion has certain guiding significance for the rescue channel excavation under the condition that the collapsed accumulation body blocks the roadway after the coal mine disaster. [ABSTRACT FROM AUTHOR]

The carbothermic reduction of vanadium titanomagnetite concentrate (VTC) with the assistance of Na2CO3 was conducted in an argon atmosphere between 1073 and 1473 K. X-ray diffraction and scanning electron microscopy were used to investigate the phase transformations during the reaction. By investigating the reaction between VTC and Na2CO3, it was concluded that molten Na2CO3 broke the structure of titanomagnetite by combining with the acidic oxides (Fe2O3, TiO2, Al2O3, and SiO2) to form a Na-rich melt and release FeO and MgO. Therefore, Na2CO3 accelerated the reduction rate. In addition, adding Na2CO3 also benefited the agglomeration of iron particles and the slag—metal separation by decreasing the viscosity of the slag. Thus, Na2CO3 assisted carbothermic reduction is a promising method for treating VTC at low temperatures. [ABSTRACT FROM AUTHOR]

The study aimed to investigate the bioaccessibility and the stability of purified ethanol extracts (PEE) from Cudrania cochinchinensis roots, and the changes in antioxidant activity and enzyme inhibition activity and cytotoxicity by in vitro digestion. No compounds were lost during the gastrointestinal digestion (GID) process, 15 compounds were tentatively identified using UPLC-TOF-MS/MS technology, including five phenolic and ten flavonoid compounds. After the gastric digestion (GD), the bioaccessibility of phenolic and flavonoid compounds was 55.66% and 52.44%, respectively. After the intestinal digestion (ID), the bioaccessibility of phenolic and flavonoid compounds reduced to 39.70% and 33.36%, respectively. The gastrointestinal digestion (GID) decreased the bioaccessibility of phenolic compounds. All compounds were affected throughout the gastrointestinal digestion (GID), among which the more affected compounds were 4-hydroxybenzoic acid, eriodictyol-7-O-glucoside, resveratrol and 3,6,3',4'-tetrahydroxyflavone (compared with the peak intensity of the undigested PEE). Furthermore, there was a reduction in the antioxidant activity, inhibition activity against α-glucosidase and tyrosinase, and cytotoxicity toward HepG2 cells of the PEE after GID. There was a significantly positive correlation between the bioactivity and the total phenolic/flavonoid contents. The results showed that in vitro digestion had significant effects on the phenolic content and bioactivity. Although phenolic contents were decreased during GID, C. cochinchinensis roots is still a good source of bioactive compounds for the development of functional foods with health benefits. [ABSTRACT FROM AUTHOR]

The diagnosis of drug-induced anaphylactic death is an important component of forensic medicine. The purpose of this study was to explore the expression of FcεRIα and tryptase in human lung tissue during drug-induced anaphylactic death and its value for forensic medicine. The expression of FcεRIα and tryptase in lung tissues of the drug-induced anaphylactic death group (n = 30) and control group (who died due to sudden cardiac death, falling from a height, or traffic accidents, n = 30) was detected by immunohistochemistry and immunofluorescence staining. The difference in FcεRIα and tryptase expression in the lung tissue between the drug-induced anaphylactic death group and the control group was statistically significant (p < 0.05). The levels of FcεRIα and tryptase expression greatly increased in the lung tissue of the drug-induced anaphylactic death group, which may provide morphological evidence and a reference for the diagnosis of drug-induced anaphylactic death in forensic medicine. [ABSTRACT FROM AUTHOR]

The lobula giant movement detector (LGMD) is the movement-sensitive, wide-field visual neuron positioned in the third visual neuropile of lobula. LGMD neuron can anticipate collision and trigger avoidance efficiently owing to the earlier occurring firing peak before collision. Vision chips inspired by the LGMD have been successfully implemented in very-large-scale-integration (VLSI) system. However, transistor-based chips and single devices to simulate LGMD neurons make them bulky, energy-inefficient and complicated. The devices with relatively compact structure and simple operation mode to mimic the escape response of LGMD neuron have not been realized yet. Here, the artificial LGMD visual neuron is implemented using light-mediated threshold switching memristor. The non-monotonic response to light flow field originated from the formation and break of Ag conductive filaments is analogue to the escape response of LGMD neuron. Furthermore, robot navigation with obstacle avoidance capability and biomimetic compound eyes with wide field-of-view (FoV) detection capability are demonstrated. Development of real-time sensing capability in artificial vision system requires an integration that allow sensing, computation, and storage, whilst remain energy efficient and compact. Here, the authors mimic the lobula giant movement detector to achieve this objective via light-mediated threshold switching memristor. [ABSTRACT FROM AUTHOR]

Background: Postoperative nausea and vomiting (PONV) occur in up to 30 percent of patients after breast cancer surgery despite routine administration of antiemetic prophylaxis. A history of nausea and vomiting during pregnancy (NVP) has been reported as a risk factor of intraoperative nausea and vomiting in caesarean delivery. Nevertheless, whether a history of severe nausea and vomiting during pregnancy (SNVP) is associated with a higher occurrence of PONV remains unclear. Methods: In this study, 121 sequential female patients who were scheduled to undergo breast cancer surgery were assigned to study group (30 cases, with SNVP) or control group (91 cases, with mild NVP (MNVP)). The incidence of PONV and the need for rescue antiemetic were recorded in post-anesthesia care unit (PACU), at 6 h, 12 h, 24 h, and 36 h after operation. Moreover, postoperative pain, level of satisfaction, and the relationship of ER/PR status in breast cancer tissue with SNVP and PONV were also investigated. Results: Data from 115 patients were analyzed. The incidence of PONV in the SNVP group was significantly higher than that in the MNVP group at 6 h (P < 0.005), 12 h (P < 0.05), and 24 h after the operation (P < 0.05). The incidence of PONV in the MNVP group was approximately 30% lower than in the SNVP group. Besides, more severe PONV, a larger number of demands for rescue antiemetic, fewer patient satisfaction scores, and more dizziness were observed in the SNVP group. Yet, no relationship was found between ER/PR status of breast cancer tissue and SNVP or PONV. Conclusions: Compared to patients with MNVP, those with a history of SNVP experienced a higher incidence of PONV and severe PONV, presented with a larger number of requirements for postoperative antiemetic and a lower level of satisfaction. [ABSTRACT FROM AUTHOR]

Collapse is a major geological disaster that occurs during mountain tunnel construction. However, the accuracy of collapse risk assessment is generally restricted by evaluation factors or methods. This paper proposes a novel integrated collapse risk evaluation method for mountain tunnels based on case-based reasoning, rough set theory, and unascertained measure-set pair analysis (UM-SPA) theory. First, the risk surroundings and risk factors involved in tunnel collapse are summarized by the analytic hierarchy process, and a preliminary risk evaluation index system is established. Then, an attribute reduction algorithm based on the conditional information entropy of a rough set is proposed and applied to cases with similar attribute characteristics as those of the tunnel to be evaluated, to remove the relatively insignificant or redundant indices and improve the reliability of risk assessment. Finally, taking the relationship between tunnel collapse and its evaluation indices as an unascertained system, Set Pair Analysis (SPA) theory is introduced to optimize the credible degree recognition criteria of unascertained measure theory (UMT). Combined with the modified entropy weight method, a UM-SPA model for tunnel collapse risk evaluation is established to calculate the level of collapse risk quantitatively and predict the development trend of risk dynamically. Taking Xiucun Tunnel passing through fault F18 as an example, collapse risk is evaluated and compared with the evaluation results of traditional UMT and field status. The results demonstrate the feasibility and efficiency of the proposed approach and provide a new idea for collapse risk prediction while constructing mountain tunnels. [ABSTRACT FROM AUTHOR]

Ketamine is a recreational drug that causes emotional and cognitive impairments, but its specific mechanisms of action are still unclear. Recent evidence suggests that Tau protein phosphorylation and targeted delivery to the postsynaptic area are closely related to its neurotoxicity, and our recent studies have shown that long-term ketamine administration causes excessive Tau protein phosphorylation. However, the regulatory mechanism of Tau protein phosphorylation induced by ketamine has not been clarified. In the present study, we administered a single ketamine injection and long-term (6 months) ketamine injections in C57BL/6 mice, to investigate the effects of different doses of ketamine on the expression levels of Tau protein and its phosphorylation, the expression levels and activities of the related protein phosphokinases GSK-3β and CDK5, and the expression levels and activities of the related protein phosphatases PP2A and PP2B in the mouse hippocampus. Our results showed that both single-dose and long-term ketamine administration induced excessive phosphorylation of the Tau protein at ser202/thr205 and ser396. A single ketamine administration caused an increase in the activity of GSK-3β (at high doses) and a decrease in the activity of PP2A. On the other hand, long-term ketamine administration resulted in an increase in the activities of GSK-3β (at high doses) and CDK5, and a decrease in the activity of PP2A. Our results indicate that GSK-3β, CDK5, and PP2A may be involved in ketamine-induced Tau protein phosphorylation. [ABSTRACT FROM AUTHOR]

The line and slope fine-tuning is the process of optimizing the horizontal and longitudinal sections to meet the requirements of building clearance, which is an indispensable step in the building engineering. The traditional line and slope fine-tuning, which is manually completed by designers, depends heavily on the domain knowledge of designers. The more experienced the designer is, the better the effect of line and slope fine-tuning will be. This paper makes a first attempt to apply the evolutionary algorithm to the process of line and slope fine-tuning. The main work includes: a new denoising method for tunnel point cloud data is proposed to remove noisy and redundant data from point cloud; an objective function is given to measure the deviation between the design tunnel and the real tunnel; and a learning model of the line and slope fine-tuning is built based on the point cloud data and evolutionary algorithm. A dataset from a length of the real metro tunnel is used for model testing. The testing results show that, in comparison with the traditional manually-adjusting method, our approach based on the evolutionary algorithm can significantly reduce the deviation between the adjusted tunnel and the real tunnel. [ABSTRACT FROM AUTHOR]

Nanoporous structures constructed by small molecular components exhibited vigorous materials potentials. While maintianing uniform porosity and functional properties, more applicable processing methods for the solid powders need to be considered and the improvement of binding interactions represents a preferable approach for structural flexibility. Here, by combining ionic interaction and host-guest inclusion, we constructed flexible supramolecular frameworks composing of inorganic polyanionic clusters, cationic organic hosts, and a bridging guest. The formed layer framework structure assemblies grew into nano-fibers and then supramolecular gels, donating highly convenient processability to porous materials. A simple spin-coating generated a new type of liquid separation membranes which showed structural stability for many liquids. The surface properties can be facilely modulated via filling a joystick liquid and then a hydrophilic/hydrophobic liquid into the porous frameworks, providing in-situ consecutive switchings for cutting liquids. This strategy extends the potential of flexible supramolecular frameworks for responsive materials in the laboratory and in industry. Porous materials show potential in various technological fields but processing of these materials remains challenging which hampers their application. Here the authors demonstrate an organic/inorganic framework composed of a supramolecular gel as processable porous material. [ABSTRACT FROM AUTHOR]

Recent genome-wide association studies (GWAS) in European descent population have identified more than 30 independent single-nucleotide polymorphisms (SNPs) associated with Alzheimer's disease (AD). In the present study, we genotyped 39 AD-risk SNPs in 499 sporadic AD patients and 760 matched healthy controls of Mongolian ethnicity from the Inner Mongolia, China. Further, we investigated whether genetic risk score (GRS) combining multiple AD-risk loci confirmed in our study population could improve AD prediction. Two approaches were used for GRS calculation: a simple risk allele count (cGRS) and a weighted approach (wGRS). The area under the receiver operating characteristic curve (AUC) was used to compare the discriminatory ability of the GRS models. Seven SNPs were confirmed associated with AD and four SNPs were associated with AD risk independent of APOE genotypes in our population. GRS based on either seven SNPs or four APOE-independent SNPs were significantly associated with AD risk (P = 2.3E−17~2.0E−6). The AUC for wGRS was significantly greater than for cGRS (0.6416 versus 0.6339, P = 0.0049 for seven SNPs; 0.5857 versus 0.5765, P = 0.0047 for four APOE-independent SNPs). Furthermore, we found that wGRS combining four APOE-independent SNPs and APOE E4 genotypes reached AUC 0.7023, significantly better than the discriminate ability of APOE E4 genotypes alone (AUC = 0.6699, P = 0.0379). The combined model, with an AUC of 0.6989, significantly higher than that of APOE E4 alone (0.6529) (P = 0.0284), for subjects in a validation cohort comprising 250 cases and 380 controls, randomly selected from our original cohort. In summary, we found that wGRS based on four APOE-independent AD risk SNPs may supplement APOE E4 for better assessing individual risk for AD in Mongolian population in China. [ABSTRACT FROM AUTHOR]

Recent research has identified some risk factors for smartphone addiction. However, scarce research has examined the potential influence of sensation seeking on smartphone addiction, and little is known regarding the mediating mechanisms underlying this relationship. The present study examined the predictive role of sensation seeking on adolescent smartphone addiction and investigated whether fear of missing out (FoMO) and procrastination sequentially mediated the relation between sensation seeking and adolescent smartphone addiction. A sample of 794 adolescents completed questionnaires regarding demographics, sensation seeking, FoMO, procrastination, and smartphone addiction. After controlling for demographic covariates, the results indicated that (a) sensation seeking was positively associated with smartphone addiction; (b) both FoMO and procrastination partially mediated the relation between sensation seeking and adolescent smartphone addiction; and (c) FoMO and procrastination sequentially mediated the relation between sensation seeking and adolescent smartphone addiction. This study highlights the underlying mechanisms between sensation seeking and adolescent smartphone addiction, which has important implications for the preventions and interventions of adolescent problematic smartphone use in this digital era. [ABSTRACT FROM AUTHOR]

Fatal subarachnoid hemorrhage (SAH) caused by anterior communicating artery (ACoA) rupture is a rare event in medicolegal practice. Anatomical variations of the ACoA tend to make its anatomical structure, and as a result, blood flow through it, more complicated, which may increase hemodynamic stress and cause weak spots in the affected blood vessels. Variant ACoAs are prone to rupture in the event of a blunt-force trauma. Here, we report a fatal case of SAH caused by the rupture of a variant ACoA when the victim's head was struck from behind, causing the head to rotate and the victim to fall forward onto the ground. A medicolegal autopsy revealed diffuse basal SAH and ACoA duplication. The smaller of the two variant ACoA branches had ruptured near its junction with the right anterior cerebral artery. No basal aneurysms or other fatal diseases or injuries were found. This case highlights the significance of anatomical variation in forensic pathology. [ABSTRACT FROM AUTHOR]

A partition of unity (PU) based four-node tetrahedral element with continuous nodal stress (Tetr4-CNS) was recently proposed for static analysis of three-dimensional solids. By simply using the same mesh as the classical four-node tetrahedral (Tetr4) element, high order global approximation function in the Tetr4-CNS element can be easily constructed without extra nodes or nodal DOFs. In this paper, the Tetr4-CNS element is further applied in the analysis of three dimensional dynamic problems. A series of free vibration and forced vibration problems are solved using the Tetr4-CNS element. The numerical results show that, for regular meshes, accuracy obtained using the Tetr4-CNS element is superior to that obtained using the Tetr4 and eight-node hexahedral (Hexa8) elements. For distorted meshes, the Tetr4-CNS element has better mesh-distortion tolerance than both the Tetr4 and Hexa8 elements. [ABSTRACT FROM AUTHOR]

Dynamical compactness with respect to a family as a new concept of chaoticity of a dynamical system was introduced and discussed in Huang et al. (J Differ Equ 260(9):6800-6827, 2016). In this paper we continue to investigate this notion. In particular, we prove that all dynamical systems are dynamically compact with respect to a Furstenberg family if and only if this family has the finite intersection property. We investigate weak mixing and weak disjointness by using the concept of dynamical compactness. We also explore further difference between transitive compactness and weak mixing. As a byproduct, we show that the ωF-limit and the ω-limit sets of a point may have quite different topological structure. Moreover, the equivalence between multi-sensitivity, sensitive compactness and transitive sensitivity is established for a minimal system. Finally, these notions are also explored in the context of linear dynamics. [ABSTRACT FROM AUTHOR]

To unravel the ecological function played by pioneer plants in the practical restoration of mine tailings, it is vital to explore changes of soil characteristics and microbial communities in rhizosphere and bulk soil following the adaptation and survival of plants. In the present study, the diversity and structure of rhizospheric bacterial communities of three pioneer plants in copper mine tailings were investigated by Illumina MiSeq sequencing, and the effects of pioneer plants on soil properties were also evaluated. Significant soil improvement was detected in rhizospheric samples, and Alnus cremastogyne showed higher total organic matter, total nitrogen, and available phosphorus than two other herbaceous plants. Microbial diversity indices in rhizosphere and bulk soil of reclaimed tailings were significantly higher than bare tailings, even the soil properties of bulk soil in reclaimed tailings were not significantly different from those of bare tailings. A detailed taxonomic composition analysis demonstrated that Alphaproteobacteria and Deltaproteobacteria, Chloroflexi, Acidobacteria, and Gemmatimonadetes showed significantly higher relative abundance in rhizosphere and bulk soil. In contrast, Gammaproteobacteria and Firmicutes were abundant in bare tailings, in which Bacillus, Pseudomonas, and Lactococcus made up the majority of the bacterial community (63.04%). Many species within known heavy metal resistance and nutrient regulatory microorganism were identified in reclaimed tailings, and were more abundant among rhizospheric microbes. Hierarchical clustering and principal coordinate analysis (PCoA) analysis demonstrated that the bacterial profiles in the rhizosphere clustered strictly together according to plant types, and were distinguishable from bulk soil. However, we also identified a large shared OTUs that occurred repeatedly and was unaffected by highly diverse soil properties in rhizosphere and bulk samples. Redundancy analysis indicated that water content and Cu and As concentrations were the main environmental regulators of microbial composition. These results suggest that the interactive effect of pioneer plants and harsh soil environmental conditions remodel the specific bacterial communities in rhizosphere and bulk soil in mine tailings. And A. cremastogyne might be approximate candidate for phytoremediation of mine tailings for better soil amelioration effect and relative higher diversity of bacterial community in rhizosphere. [ABSTRACT FROM AUTHOR]

The objective of this study was to unveil insights into the effects of Saccharomyces cerevisiae on the development of volatile compounds and metabolites during the dough fermentation in making Chinese steamed bread. Changes in gluten structure under the influence of baker’s yeast were studied using scanning electron micrographs (SEM). A unique aroma profile was found comprising some previously reported aromatic compounds and some unreported aromatic aldehydes ((E)-2-Decenal and 2-Undecenal) and ketones (2-Heptanone and 2-Nonanone) in the baker’s yeast fermentation. Among metabolites, the most preferred sugar for this yeast (glucose) showed a significant decrease in contents during the initial few hours of the fermentation and at last an increase was observed. However, most of the amino acids increased either slightly or decreased by the fermentation time. SEM of fermented dough showed that the yeast had a very little effect on starch stability. This study provided some fermentation features of the bakers’ yeast which could be used for the tailored production of steamed bread. [ABSTRACT FROM AUTHOR]

Inflammatory damage aggravates the progression of Alzheimer’s disease (AD) and the mechanism of inflammatory damage may provide a new therapeutic window for the treatment of AD. Toll-like receptor 4 (TLR4)-mediated signaling can regulate the inflammatory process. However, changes in TLR4 signaling pathway induced by beta-amyloid (Aβ) have not been well characterized in brain, especially in the hippocampus. In the present study, we explored the changes of TLR4 signaling pathway induced by Aβ in the hippocampus and the role of atorvastatin in modulating this signal pathway and neurotoxicity induced by Aβ. Experimental AD rats were induced by intrahippocampal injection of Aβ1-42, and the rats were treated with atorvastatin by oral gavage from 3 weeks before to 6 days after injections of Aβ1-42. To determine the spatial learning and memory ability of rats in the AD models, Morris water maze (MWM) was performed. The expression of the glial fibrillary acidic protein (GFAP), ionized calcium binding adapter molecule-1 (Iba-1), TLR4, tumor necrosis factor receptor-associated factor 6 (TRAF6), and nuclear transcription factor (NF)-κB (NF-κB) protein in the hippocampus was detected by immunohistochemistry and Western blot. Compared to the control group, increased expression of TLR4, TRAF6, and NF-κB was observed in the hippocampus at 7 days post-injection of Aβ (P < 0.01). Furthermore, atorvastatin treatment significantly ameliorated cognitive deficits of rats, attenuated microglia and astrocyte activation, inhibited apoptosis, and down-regulated the expression of TLR4, TRAF6, and NF-κB, both at the mRNA and protein levels (P < 0.01). TLR4 signaling pathway is thus actively involved in Aβ-induced neuroinflammation and atorvastatin treatment can exert the therapeutic benefits for AD via the TLR4 signaling pathway. [ABSTRACT FROM AUTHOR]

Caspase-3 activation and apoptosis are associated with various neurodegenerative disorders. Calcium activation is an important factor in promoting apoptosis. We, therefore, assessed the role of intracellular calcium in ethanol-induced activation of caspase-3 in H4 human neuroglioma cells and the protective effect of the NMDA receptor antagonist, memantine, on ethanol-induced apoptosis in H4 cells. H4 cells were treated with 100 mM EtOH (in culture medium) for 2 days. For interaction studies, cells were treated with memantine (4 μM), EDTA (1 mM), or BAPTA-AM (10 μM) before treatment with EtOH. Knockdown of the gene encoding the NR1 subunit of the NMDA receptor was performed using RNAi. Apoptosis was detected by Annexin V-FITC/PI staining and flow cytometry. Cell viability was detected using an MTS cell proliferation kit. Fluorescence dual wavelength spectrophotometry was used to determine the intracellular calcium concentration. The levels of NR1, caspase-3, IP3R1, and SERCA1 proteins were detected by western blotting. NR1, IP3R1, and SERCA1 mRNA levels were detected by qPCR. We observed increased expression of NR1, IP3R1, SERCA1, and increased intracellular levels of calcium ions in H4 cells exposed to ethanol. In addition, the calcium chelators, EDTA and BAPTA, and RNAi disruption of the NMDA receptor reduced ethanol-induced caspase-3 activation in H4 cells. Memantine treatment reduced the ethanol-induced increase of intracellular calcium, caspase-3 activation, apoptosis, and the ethanol-induced decrease in cell viability. Our results indicate that ethanol-induced caspase-3 activation and apoptosis are likely to be dependent on cytosolic calcium levels and that they can be reduced by memantine treatment. [ABSTRACT FROM AUTHOR]

A new terbium sensitized spectrofluorimetric method was developed for the determination of trace amounts of dopamine (DA) using ethylenediaminetetraacetic acid as co-ligand and cetyltrimethylammonium chloride as sensitizer. UV absorption and fluorescent spectra were used to investigate the photophysical properties of the ternary complex. Under the optimum conditions, the enhanced fluorescence intensities of the Tb(III) complexes increased linearly with the concentration of DA over the ranges 8 × 10-5 × 10 M and the limit of detection for DA was found to be 2.4 × 10 M. The proposed method has been applied for the quantitative determination of DA in a pharmaceutical preparation and urine samples. The possible energy transfer mechanisms in the lanthanide complexes were discussed. [ABSTRACT FROM AUTHOR]

In this study, bacterial community compositions in seven different estuarine sediments of Poyang Lake were analyzed using 16S rRNA gene-targeted metagenomic approach. Remarkable differences in the bacterial diversity were observed in these different estuarine sediments. Le, Chang and Rao river samples exhibited the higher bacterial diversity; the Fu river sample showed the less diversity. Bacterial richness and diversity were positively regulated by sediment inorganic phosphorus, and nitrite nitrogen, total phosphorus and inorganic phosphorus were found to be important drivers for bacterial community compositions. Proteobacteria, Acidobacteria, Firmicutes, Chloroflexi, Bacteroidetes, Planctomycetes, Gemmatimonadetes, Actinobacteria, Nitrospirae, and Verrucomicrobia were the major components of sediment bacterial communities. Among them, Proteobacteria was the most dominant phylum, followed by Acidobacteria and Firmicutes. Our study gives a comprehensive insight into the structure of bacterial community of the different estuarine sediments of Poyang Lake, indicating that the environmental factors played a key role in influencing the bacterial community composition in the freshwater ecosystem. [ABSTRACT FROM AUTHOR]

Single particle mass spectrometry has been widely used to determine the size and chemical compositions of atmospheric aerosols; however, it is still rarely used for the microphysical properties measurement. In this study, two methods were developed for determining aerosol effective density by a single particle aerosol mass spectrometer (SPAMS). Method I retrieved effective density through comparison between measured light scattering intensities and Mie theoretical modelled partial scattering cross section. Method II coupled a differential mobility analyzer (DMA) with SPAMS to simultaneously determine the electric mobility and vacuum aerodynamic diameter, and thus the effective density. Polystyrene latex spheres, ammonium sulfate and sodium nitrate were tested by these methods to help validate their effectiveness for determining the aerosol effective density. This study effectively extends SPAMS measurements to include particle size, chemical composition, light scattering, and effective density, and thus helps us better understand the environment and climate effects of aerosols. [ABSTRACT FROM AUTHOR]