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Most of the intrinsic photocatalysts with visible light response can only generate one active radical due to the limitation of their band structures, which is immediate cause limiting their photocatalytic degradation performance. In this work, ZnIn

The hydroxyl radical (˙OH) is one of the most important oxidizing species in air whose concentration indicates the air quality. In this work, an indirect method was developed to determine ˙OH based on the electrochemical signal of 2,5-dihydroxybenzoic acid (2,5-DHBA), a specific reaction product of salicylic acid and ˙OH. The molecular imprinting technique was introduced into this work to improve the selectivity and sensitivity of this method. 2,5-DHBA was imprinted on reduced graphene oxide (rGO) via a simple electrochemical method by using pyrrole as the functional monomer. rGO not only provides abundant active sites for 2,5-DHBA imprinting but also improves the conductivity and mass transportation and increases the accessibility of active sites for 2,5-DHBA recognition. The differential pulse voltammetry (DPV) signals of 2,5-DHBA were used to evaluate the performance of the molecularly imprinted polymer (MIP) based sensor. The linear range for the concentration of 2,5-DHBA was from 5.0 × 10−8 to 4.5 × 10−5 M and the detection limit was down to 2.74 × 10−9 M. A linearity for ˙OH concentration ranging from 8.4 × 106 to 7.5 × 109 molecules per cm3 was obtained. The low detection limit for ˙OH was down to 4.6 × 105 molecules per cm3 when using this sensor. The atmospheric ˙OH concentration in Yangzhou has been successfully detected by this method. This work extended the molecularly imprinted polymers to the indirect detection of ˙OH in the atmosphere with a simplified sample collection and detection process and good sensitivity.

The hydroxyl radical (•OH) plays important roles in environment and health problems. However, the short life time and low concentrations of •OH limited its detection. In this work, a simple method has been successfully performed for the sensitive detection of hydroxyl radical based on an activated glassy carbon electrode (AGCE).4-hydroxybenzoic acid (4-HBA) was used as a trapping agent for •OH radicals, leading to the production of electroactive 3,4-dihydroxybenzoic acid (3,4-DHBA). Different procedures including polarisation and cyclic voltammetry in acid or base solutions have been used to activate the glassy carbon electrodes. The electrochemical behaviours of 3,4-DHBA on these activated electrodes were studied and compared. Experimental results showed that the glassy carbon electrode polarised in H2SO4 (AGCE-P/H2SO4) has the greatest sensitivity and reproducibility to 3,4-DHBA. 3,4-DHBA performed a linear relationship from 1.0 × 10−7 to 1.0 × 10−4 M on the AGCE-P/H2SO4. The detection limit was...

Soil organic carbon (SOC) is an important component of the global carbon pool. It is a critical indicator of soil quality. We studied SOC content (SOCC) and SOC density (SOCD) of the Three Gorges Reservoir (TGR) area in China. Soil samples from 306 sites across the study area were assessed for SOCC, SOCD and bulk density. Total SOC stocks in the TGR area were estimated at 5.82 × 10 − 1 Pg. We examined relationships between SOCC and SOCD, and the environmental and land-use/land-cover (LULC) variables. The plow layer (0–0.3 m) had a significantly higher mean SOCC (20.6 g kg − 1 ) than the subsoil layer (16.5 g kg − 1 ); elevation, LULC, soil type and soil thickness were the most influential factors affecting SOCC in the plow layer. In the subsoil layer, elevation and soil thickness were dominant in determining SOCC and SOCD. To study the spatial variability of SOC, we used statistical modeling and GIS-based techniques to map the distribution of SOCC and SOCD of the study area. Both SOCC and SOCD in the plow layer showed patchy distribution and were positively correlated with elevation and vegetation coverage. Spatial variability of SOCD in the subsoil layer showed a gradual transition between LULC categories. The lower SOCC of farmland appeared to be related to the repeated removal of agricultural produce from the land. Preservation of permanent vegetation cover and changing of the traditional farming practices will help to improve SOC stock and increase soil productivity in the TGR area.

Multi-carbonyl macrocyclic compounds have recently attracted much attention due to their high performance relative to some short chain carbonyl compounds as the cathode active constituents for lithium-ion batteries (LIBs). However, little is known about the evolution mechanism of their electrochemical properties during charging and discharging processes. In this paper, the application of density functional calculations at the M06-2X/6-31G(d,p) level of theory is presented to study systematically the electrochemical properties of pillar[5]quinone (P5Q) as a cathode active material for LIBs. The optimized structures of P5Q accepting different number of electrons and binding different number of lithium atoms are obtained, respectively. The geometry structure, thermodynamics property, electronic structural property, solvent effect and redox potential are discussed in detail. The uneven-distribution of extra electrons in several P5Qn− anions can minimize the repulsive interactions as far as possible. The macrocyclic skeletons in P5QLin structures are distorted to different extents by the binding interactions between Li atoms and P5Q. More than eight intercalated lithium atoms into per P5Q molecule are confirmed in this work, indicating a high utilization ratio of carbonyl groups of P5Q as a cathode material. Compared with pillar[4]quinone and pillar[6]quinone, P5Q is predicted to have better cycling performance due to its higher structural stability.

This study aimed to develop a proper control strategy for a forced-circulation ice thermal storage system (ITSS) designed for a permanent refuge chamber with an accommodation capacity of 50 persons. The heat transfer characteristics of the ITSS were investigated through theoretical and experimental approaches. A quasi-steady one-dimensional mathematical model for predicting the transient discharging power was proposed. On this basis, a control strategy was proposed to fulfill the minimum cooling requirement in consideration of both effective discharging time and human comfort. The minimum required velocity of the ITSS was analyzed; from this, the effective working time of the ITSS was determined to be 64.57 h. Additionally, the heat load inside the chamber was found to be the main factor that affected the effective temperature control duration and the utilization ratio of the ice. Thus, a reserve factor, which is defined as a function of rated heat load and determined by the discharging performance model, is suggested for consideration during optimization.

In this paper, we report a novel imino bridged pillar[5]arene derivative ( P5N ) for the first time. Four conformers ( P5N0 , P5N1 , P5N12 , and P5N13 , arising due to the different orientation of N H bond of imino bridging group) are obtained by quantum chemical calculations at the CAM-B3LYP/6-31+G(d, p) level of theory. The geometries, energies, electronic structures, and absorption spectra of P5N conformers as well as pillar[5]arene ( P5 ) are discussed in detail. The inclusion complexes of paraquat ( Pq ) with P5N and P5 , respectively, are also obtained at the same level of theory. Compared to P5 , P5N exhibits better performance in inclusion complexation toward Pq .

The vibration signal of rolling bearing is complex, it is difficult to extract fault features and diagnose accurately. In this paper, a rolling bearing fault diagnosis method based on variational mode decomposition and GWO-LSSVM is proposed. The variational mode decomposition algorithm is used to decompose the bearing vibration signal, and the fuzzy entropy of each component signal is calculated. GWO is used to optimize the parameters of LSSVM. The least square support vector machine is used to identify the bearing fault.

Alpha-synuclein (α-Syn) is a major component of Lewy bodies, abnormal protein aggregates that are present in neurons of patients with Parkinson's disease and other neurological disorders. Despite intensive investigation, the in vivo role of α-Syn in physiological and pathological processes is not fully understood. This study addresses a current debate on the nuclear localization of α-Syn protein in the brain. To assess the specificity of various α-Syn antibodies, we compared their staining patterns in wild-type mouse brains with that of the α-Syn knock-out mice. Among five different α-Syn antibodies tested here, two generated intensive nuclear staining throughout the normal mouse brain. However, nuclear staining by these two antibodies was also present in neurons of the α-Syn knock-out mice. This provides evidence that the nuclear signal is not specifically related to the presence of α-Syn, but it rather results from the cross-reactivity of the two antibodies to some unknown antigens in neuronal nuclei. In mouse brain neurons, endogenous α-Syn proteins are primarily localized to neuronal processes and nerve terminals but present only at low levels in the cell bodies. This is different from a generally uniform distribution of exogenously expressed α-Syn in both cytoplasm and nuclei of heterologous cells and suggests that the neuritic enrichment of α-Syn in neurons may be mediated by their specific interactions with certain structural or molecular components in the neuropil.

The effects of cavity-dispersion noncoaxiality (CDN) on the generation of ultrabroadband femtosecond pulses in KLM Ti:sapphire laser were investigated theoretically and experimentally. It was predicted that when the laser sub-cavity works near the coaxial operation point, the limitation of CDN on the bandwidth broadening is minimum, which is favorable for ultrabroadband pulse generation. On the basis of this prediction, femtosecond pulses with bandwidth of 650 to 1000 nm were directly generated from a home built KLM Ti:sapphire laser. To our knowledge, they are the broadest bandwidth pulses produced from KLM Ti:sapphire laser with similar oscillator configuration and gain crystal length of 3 mm.

Being as one of China's largest oil and gas producer and suppliers, China National Petroleum Corporation (CNPC), with more than 1,500,000 employees, has about 90 large and medium subsidiary enterprises, and occupational hazard inevitably occur during the construction and production operation, which has the characteristics of wide geographic distributions, enormous employees contacting hazard factors and various hazard factors resulting in occupational diseases. According to the characteristics of occupational disease hazard factors in petroleum and petrochemical industry, and characteristics of occupational health hazards for oversea operations and field operations, CNPC has set up its own occupational health (OH) management models to control occupational disease hazards from the source. In recent years, 92–97% of the employees contacting hazard factors have passed occupational health examinations and there were no hazard accidents of occupational diseases. Therefore, the job concerning OH has obtained satisfactory results.

Polygonum cuspidatum Sieb. Et Zucc. (Polygonaceae) has been traditionally used in folk medicine to treat various diseases.This study investigates the ameliorative effects of physcion 8-O-β-glucopyranoside (PSG) isolated from P. cuspidatum on learning and memory in dementia rats induced by Aβ1-40.Dementia rats were prepared by intracerebroventricular injection of Aβ1-40. PSG (5, 10, 20, and 40 mg/kg/d, for 5 d) was administered orally. Ameliorative activity of PSG in dementia rats was evaluated by the Morris water maze (MWM) test, and its mechanisms were explored by evaluating AchE activity, levels of DA, NE, and 5-HT in hippocampus, and drebrin protein expressions in hippocampus.Our results indicated that PSG (5, 10, 20, and 40 mg/kg/d) significantly inhibited the prolonged latency in dementia rats (p 0.05), and inhibitory rates were 16.5, 22.7, 33.0, and 44.8% after 5 d of learning, indicating that PSG improves learning and memory of dementia rats. Furthermore, PSG significantly decreased AchE activity (10, 20, and 40 mg/kg/d; p 0.05), increased 5-HT (20 and 40 mg/kg/d, p 0.05), NE (10, 20, and 40 mg/kg/d; p 0.05), and DA levels (5, 10, 20, and 40 mg/kg; p 0.05) in the hippocampus. Additionally, PSG obviously decreased the Aβ contents in hippocampus (10, 20, and 40 mg/kg/d; p 0.05), and up-regulated drebrin protein expressions (5, 10, 20, and 40 mg/kg/d; p 0.05).PSG can significantly enhance learning and memory in Aβ1-40-induced dementia rats, and the mechanisms may be related to increase levels of Ach, 5-HT, NE, and DA, decrease Aβ contents, and up-regulation of drebrin proteins in hippocampus.

The anion recognitions of tetra-(2-formamido) phenyl porphyrin (APP), tetra-(2-ureido) phenyl porphyrin (UPP), and their zinc derivatives (ZnAPP and ZnUPP) to three anions (Cl−, H2PO4 −, CH3COO−) were studied using quantum mechanical calculations (QM) and molecular dynamics (MD) simulations. The density functional theory (DFT) calculations at M06-2X/6-31G (d, p) level indicated that the anion recognition ability of ZnAPP was better than that of APP, and the anion selectivity was in the order Cl−

The possible roles played by growth arrest and DNA damage-inducible gene 34 (GADD34) in Alzheimer’s disease (AD) are so far less understood. In this study, we found that GADD34 was increased in the brains of AD transgenic J20 mice. The deposition of β-amyloid (Aβ) peptide is the main component of neurotic plaques in AD brain. Thus, we examined the effect of Aβ in the expression of GADD34 in human SH-SY5Y cells in vitro. Amyloid β (Aβ1-42) treatment led to increased expression of GADD34. Pretreatment with 50 nmol/L of c-Jun N-terminal kinases (JNK) inhibitor SP600125 abolished the upregulation of GADD34. c-Jun silencing by transfection with c-Jun small-interfering RNA abolished the effects of Aβ1-42 on the expression of GADD34. Importantly, chromatin immunoprecipitation studies verified the ability of c-Jun to bind to the GADD34 promoter, and this ability was increased more than 3-fold by Aβ1-42. These data suggest that the induction of GADD34 by Aβ is mediated by JNK/c-Jun pathway. Finally, depletion of GADD34 significantly rescued Aβ-induced cell apoptosis as evidenced by a marked decrease in the number of terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling (TUNEL)-positive cells. Consistently, knockdown of GADD34 attenuated caspase 3 activation induced by Aβ1-42.

In this study, we established cell models for Parkinson's disease using rotenone. An RNA interference vector targeting Parkin-associated endothelin receptor-like receptor (Pael-R) was transfected into the model cells. The results of reverse-transcription polymerase chain reaction and western blot analysis showed that Pael-R expression was decreased after RNA interference compared with the control group (no treatment) and the model group (rotenone treatment), while the rate of apoptosis and survival of dopaminergic cells did not differ significantly between groups, as detected by flow cytometry and an MTT assay. These experimental findings indicate that the Pael-R gene has no role in the changes in rotenone-induced Parkinson's disease model cells.

Patients with generalized epilepsy exhibit cerebral cortical disinhibition. Likewise, mutations in the inhibitory ligand-gated ion channels, GABAA receptors (GABAARs), cause generalized epilepsy syndromes in humans. Recently, we demonstrated that heterozygous knock-out (Hetα1KO) of the human epilepsy gene, the GABAAR α1 subunit, produced absence epilepsy in mice. Here, we determined the effects of Hetα1KO on the expression and physiology of GABAARs in the mouse cortex. We found that Hetα1KO caused modest reductions in the total and surface expression of the β2 subunit but did not alter β1 or β3 subunit expression, results consistent with a small reduction of GABAARs. Cortices partially compensated for Hetα1KO by increasing the fraction of residual α1 subunit on the cell surface and by increasing total and surface expression of α3, but not α2, subunits. Co-immunoprecipitation experiments revealed that Hetα1KO increased the fraction of α1 subunits, and decreased the fraction of α3 subunits, that associated in hybrid α1α3βγ receptors. Patch clamp electrophysiology studies showed that Hetα1KO layer VI cortical neurons exhibited reduced inhibitory postsynaptic current peak amplitudes, prolonged current rise and decay times, and altered responses to benzodiazepine agonists. Finally, application of inhibitors of dynamin-mediated endocytosis revealed that Hetα1KO reduced base-line GABAAR endocytosis, an effect that probably contributes to the observed changes in GABAAR expression. These findings demonstrate that Hetα1KO exerts two principle disinhibitory effects on cortical GABAAR-mediated inhibitory neurotransmission: 1) a modest reduction of GABAAR number and 2) a partial compensation with GABAAR isoforms that possess physiological properties different from those of the otherwise predominant α1βγ GABAARs.

A framework of web services discovery and composition based on semantic is proposed to find appropriate web services according to the requests of user. Some service discovery and composition algorithms are used in this framework. The component of service description can transfer the services requirements of the user to semantic description. When a formal service request is defined, the service discovery component queries the service repository for a service that matches the service request. In case no match is found, the composition component creates a composite service that matches the request with optimal QoS. Index Terms - Web services; service composition; quality of service; knapsack problem

Alzheimer’s disease is an irreversible, progressive neurodegenerative disorder leading invariably to death, usually within 7–10 years after diagnosis and is the leading cause of dementia in the elderly. Not only is Alzheimer’s disease a tragic disease in which people suffer from neurodegeneration in the years to come, it also becomes an incredible burden on the public health system. However, there is currently no effective treatment to halt the progression or prevent the onset of Alzheimer’s disease. This is partly due to the fact that the complex pathophysiology of Alzheimer’s disease is not yet completely understood. Recently, Golgi apparatus is found to play an important role in Alzheimer’s disease. In this review, we discuss the changes of Golgi apparatus during clinical progression and pathological development of Alzheimer’s disease. First, changes of Golgi apparatus size in Alzheimer’s disease are summarized. We then address the role of Golgi apparatus in the neuropathology of Alzheimer’s disease. Finally, the role of Golgi apparatus in the pathogenesis of Alzheimer’s disease is discussed. Understanding the contribution of Golgi apparatus dysfunction to Alzheimer’s disease and its pathophysiological basis will significantly impact our ability to develop more effective therapies for Alzheimer’s disease.

The cavity dispersion noncoaxiality (CDN) effects on broadband few-cycle pulse generation of a Kerr-lens mode-locked Ti:sapphire laser is investigated theoretically and experimentally. It is found that the influence of CDN is comparable with that of self-focusing and self-phase-modulation in the frequency-dependent mode size (FDMS) effects. Spectra extending from 680 nm to 1020 nm with pulse duration shorter than three optical cycles are favorably generated under the minimum CDN in the vicinity of the coaxial point of the sub-cavity.