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Since the boiler water-coal ratio control system is a complex system with the characteristics of non-linearity and strong coupling, water-coal ratio control is one of the most difficult problems in the coal-fired power generation process control engineering, whose control strategy is of great importance. While, in order to achieve the control of water-coal ratio effectively during the coal-fired power generation process, the neural network inverse system scheme is proposed for the control of the water-coal ratio of ultrasupercritical units. Firstly, the model for the water-coal ratio system of an ultra-supercritical unit is presented in allusion to the characteristics of the water-coal ratio control system. Then the concept of the neural network based inverse system, the principle and method of the design of the neural network inverse controller are discussed. Finally, the control scheme is verified by establishing neural network inverse system on MATLAB toolbox. The experimental results show that the neural network based inverse system models has better control effect in terms of anti-interference ability, stability time than that of PID control system. [ABSTRACT FROM AUTHOR]

MuSK is a receptor tyrosine kinase (RTK) that plays essential roles in the formation and maintenance of the neuromuscular junction. Distinct from most members of RTK family, MuSK activation requires not only its cognate ligand agrin but also its coreceptors LRP4. However, how agrin and LRP4 coactivate MuSK remains unclear. Here, we report the cryo-EM structure of the extracellular ternary complex of agrin/LRP4/MuSK in a stoichiometry of 1:1:1. This structure reveals that arc-shaped LRP4 simultaneously recruits both agrin and MuSK to its central cavity, thereby promoting a direct interaction between agrin and MuSK. Our cryo-EM analyses therefore uncover the assembly mechanism of agrin/LRP4/MuSK signaling complex and reveal how MuSK receptor is activated by concurrent binding of agrin and LRP4. [ABSTRACT FROM AUTHOR]

The article presents a study on the mechanism of sphingolipid homeostasis revealed by structural analysis of Arabidopsis serine palmitoyltransferase orosomucoid1(SPT-ORM1) complex. Topics discussed include biochemical characterization of Arabidopsis SPT and SPT-ORM1 complexes, structural determination of the AtsPT-ORM1 complex, and protein expression and purification.

Besides descriptor designing, factoring out the categorical effects of affine transformations is also an effective way to match features. This paper proposed and demonstrated a hypothesis that any coplanar orientations have limited geometrical changes when observed in the camera screen under given ranges of 3D affine transformations. Confirmatory experiments are accomplished by Matlab simulations focusing on specific influences of 3D affine transformations on similarity biases between concerned orientation changes. Statistical analyses and results show that rotations about plane axes mainly affect the geometrical biases of orientation changes. A set of fit limits standing for the biggest influences of most affine transformations in specified ranges are numerically approximated by total sample space distribution and experimental extreme values. We use these Similarity Limits of Orientation Changes (SLOC) as optimization constraints in matching problems, and an application example of planar pattern matching is given. The effectiveness and efficiency of SLOC are proved by the experimental results in Mikolajczyk and HPatches testbed. [ABSTRACT FROM AUTHOR]

CotA protein from Bacillus subtilis is of laccase activity. The solubility of recombinant CotA is low, which hinders its application. In this study, histidine tag position optimization and hydrophilic engineering were applied to increase the yield and activity of CotA protein. The results showed that the protein yield of CotA with his tag at C-terminal (CH6-CotA) was four times of that of NH6- CotA (His tag at N-terminal). Then, 23 single mutants were constructed by substitutions of hydrophobic residues with hydrophilic amino acids. Among them, the protein yield of the mutant F207Y was increased by 30%; the catalytic activity (kcat/Km) of V403T and P455S was two and three times higher than that of CH6-CotA, respectively. Finally, triple mutant F2071Y/V403T/P455S with C-terminal his-tag (CH6-TSY) was constructed. When the proteins were expressed in microanaerobic condition, the activities of mutants CH6-P455S and CH6-TSY were enhanced about 48- and 42- folds compared to that of NH6-CotA in non-static culture. [ABSTRACT FROM AUTHOR]

Background: To assess the predictors for intravenous immunoglobulin (IVIG) resistance and coronary artery lesions (CALs) in Kawasaki disease (KD). Methods: A total of 560 KD patients were reviewed retrospectively, including 410 complete KD (cKD) and 150 incomplete KD (iKD) patients. The laboratory data were compared between the IVIG-resistant and IVIG-responsive groups, as well as between the coronary artery lesions (CALs+) and without coronary artery lesions (CALs-) groups. Results: In the cKD patients, C-reactive protein (CRP) levels had a sensitivity of 65.52% and a specificity of 62.7% for predicting IVIG-resistance at a cutoff point of >100 mg/L. When albumin <32 g/L, the sensitivity and specificity for predicting IVIG-resistance were 72 and 83.19%, respectively. N-terminal pro-brain natriuretic peptide (NT-proBNP) levels had a sensitivity of 73.91% and a specificity of 76.43% for predicting IVIG-resistance at a cutoff point of >1300 pg/ml. Interleukin-6 levels had a sensitivity of 76.19% and a specificity of 61.59% at a cutoff value of >45 pg/ml. Erythrocyte sedimentation rate (ESR) levels had a sensitivity of 53.26% and a specificity of 64.14% for predicting CALs at a cutoff point of >75 mm/h. In the iKD patients, the sensitivity and specificity for predicting IVIG-resistance were 80 and 54.1% when hemoglobin <110 g/L. When proportion of neutrophils >70%, the sensitivity and specificity for predicting IVIG-resistance were 68 and 66.94%, respectively. ESR levels had a sensitivity of 70.83% and a specificity of 65.81% for predicting IVIG-resistance at a cutoff point of >80 mm/h. NT-proBNP levels had a sensitivity of 78.57% and a specificity of 56.67% for predicting IVIG-resistance at a cutoff point of >360 pg/ml. Interleukin-6 levels had a sensitivity of 70.59% and a specificity of 66. 28% at a cutoff value of >25 pg/ml. Interleukin-10 levels had a sensitivity of 64.71% and a specificity of 74.42% for predicting IVIG-resistance at a cutoff value of >8 pg/ml. ESR levels had a sensitivity of 61.82% and a specificity of 65.12% for predicting CALs at a cutoff point of >75 mm/h. Conclusions: The white blood cell count, proportion of neutrophils, hemoglobin, CRP, ESR, albumin, NT-proBNP, interleukin-6 and 10 may be effective predictors for IVIG resistance and CALs in KD patients. [ABSTRACT FROM AUTHOR]

The effectiveness of different polymers, alone or in combination, in inhibiting the crystallization of celecoxib (CEX) fromamorphous solid dispersions (ASDs) exposed to different temperatures and relative humiditieswas evaluated. It was found that polyvinylpyrrolidone (PVP) and PVP-vinyl acetate formed stronger or more extensive hydrogen bonding with CEX than cellulose-based polymers. This, combined with their better effectiveness in raising the glass transition temperature (Tg) of the dispersions, provided better physical stabilization of amorphous CEX against crystallization in the absence of moisture when compared with dispersions formedwith cellulose derivatives. In ternary dispersions containing 2 polymers, the physical stabilitywas minimally impaired by the presence of a cellulose-based polymer when the major polymer present was PVP. On exposure tomoisture, stability of the CEX ASDswas strongly affected by both the dispersion hygroscopicity and the strength of the intermolecular interactions. Binary and ternary ASDs containing PVP appeared to undergo partial amorphouseamorphous phase separation when exposed 94% relative humidity, followed by crystallization, whereas other binary ASDs crystallized directly without amorphouseamorphous phase separation. [ABSTRACT FROM AUTHOR]

Crystallographicsurface-resolved examination of protein–ZnO interactions cangreatly enhance the fundamental understanding of protein adsorptionon these technologically important solid surfaces which, in turn,will be tremendously valuable for the emerging applications of ZnO-basedbiomaterials and biosensors. We examine experimentally and via computersimulations the intriguing differences in the adsorption preferencesand binding behavior of whole immunoglobulin G (IgG) proteins to various,low-index ZnO crystal surfaces at the individual biomolecule level.By performing direct atomic force microscopy imaging, we determinethat IgG predominantly binds to the ZnO plane of (101̅0) relativeto the other three low-index planes of (0001), (0001̅), and(112̅0). This phenomenon is highly unusual, particularly consideringthe fact that the average binding energy of amino acids (AAs) on theZnO (0001) facet is higher than that on the (101̅0) plane. Inconjunction with combined Monte Carlo–molecular dynamics simulations,we further explain the possible origins of our unusual experimentalfindings with critical factors such as the specific spatial locationsof strongly binding AAs in the protein and their spatial distributionson the exterior surface of the protein. [ABSTRACT FROM AUTHOR]

γ-Secretase is an intramembrane protease responsible for the generation of amyloid-β (Aβ) peptides. Aberrant accumulation of Aβ leads to the formation of amyloid plaques in the brain of patients with Alzheimer's disease. Nicastrin is the putative substrate-recruiting component of the γ-secretase complex. No atomic-resolution structure had been identified on γ-secretase or any of its four components, hindering mechanistic understanding of γ-secretase function. Here we report the crystal structure of nicastrin from Dictyostelium purpureum at 1.95-Å resolution. The extracellular domain of nicastrin contains a large lobe and a small lobe. The large lobe of nicastrin, thought to be responsible for substrate recognition, associates with the small lobe through a hy-drophobic pivot at the center. The putative substrate-binding pocket is shielded from the small lobe by a lid, which blocks substrate entry. These structural features suggest a working model of nicastrin function. Analysis of nicastrin structure provides insights into the assembly and architecture of the γ-secretase complex. [ABSTRACT FROM AUTHOR]

The influence of the vanadium substituted LiNi0.5Co0.2Mn0.3O2 (LNCM-532) cathode materials on the structure and electrochemical properties were investigated by means of X-ray diffraction, Rietveld refinement, scanning electron microscope, X-ray photoelectric spectroscopy, energy dispersive spectrometer, electrochemical impedance spectroscopy, cyclic voltammetry and galvanostatic charge/discharge tests. XRD, EDS, XPS results show that vanadium is successfully substituted for the transitional metal in LiNi0.5Co0.2Mn0.3O2 crystal lattice. Rietveld refinement results show that suitable vanadium substitution leads to low cation mixing. Electrochemical tests show that the discharge capacity of Li[Ni0.5Co0.2Mn0.3]0.97V0.03O2 at 5 C remains 72.2% of that at 0.1 C, while the capacity retention is only 58.9% for LiNi0.5Co0.2Mn0.3O2. LiNi0.5Co0.2Mn0.3O2 exhibits the capacity retention of 93.9% at 1 C after 50 cycles. After substituting, the capacity retention of Li[Ni0.5Co0.2Mn0.3]0.97V0.03O2 is increased to 96.3% at 1 C. EIS measurement indicates that vanadium substitution contributes to the better lithium ion diffusion and the lower charge transfer resistance. [ABSTRACT FROM AUTHOR]

Subclass III SnRK2s (SnRK2.6/2.3/2.2) are the key positive regulators of abscisic acid (ABA) signal transduction in Arabidopsis thaliana. The kinases, activated by ABA or osmotic stress, phosphorylate stress-related transcription factors and ion channels, which ultimately leads to the protection of plants from dehydration or high salinity. In the absence of stressors, SnRK2s are subject to negative regulation by group A protein phosphatase type 2Cs (PP2C), whereas the underlying molecular mechanism remains to be elucidated. Here we report the crystal structure of the kinase domain of SnRK2.6 at 2.6-Å resolution. Structure-guided biochemical analyses identified two distinct interfaces between SnRK2.6 and ABI1, a member of group A PP2Cs. Structural modeling suggested that the two interfaces lock SnRK2.6 and ABI1 in an orientation such that the activation loop of SnRK2.6 is posited to the catalytic site of ABI1 for dephosphorylation. These studies revealed the molecular basis for PP2Cs-mediated inhibition of SnRK2s and provided important insights into the downstream signal transduction of ABA. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates elemene's ability to pass through the blood-brain barrier and its effect on brain cancer. The study uses the G-422 tumour cell model in mice to examine the effectiveness of elemene in brain tumours treatment. Results show that the chemical can pass through the blood-brain barrier and is effective of treating cerebral malignancy.

Abstract  The frequency, type and distribution of simple sequence repeats (SSRs) in Porphyra haitanensis genomes was investigated using expressed sequence tag (EST) data deposited in public databases. A total of 3,489 non-redundant P. haitanensis ESTs were screened for SSRs using SSRhunter software. From those, 224 SSRs in 210 ESTs were identified; trinucleotides were the most common type of SSR (64.29%), followed by dinucleotides (33.48%). Tetranucleotides, pentanucleotides, and hexanucleotides were not common. Among all identified motif types, CGG/CCG had the highest frequency (33.9%), followed by TC/AG (24.6%). From these EST-SSRs, 37 SSR primer-pairs were designed and tested using common SSR reaction conditions with 15 P. haitanensis DNAs as templates. The results showed that 28 SSR primer-pairs gave good amplification patterns. These were used to conduct SSR analyses of genetic variations of the 15 germplasm strains of P. haitanensis. A total of 224 alleles were detected, with the number of alleles ranging from 4 to 15. The effective number of alleles, expected heterozygosity, and polymorphism information content of the 15 germplasm strains of P. haitanensis were 2.81, 0.64, and 0.57, respectively. All of these parameters indicate that the 15 germplasm strains of P. haitanensis harbor rich genetic variation. [ABSTRACT FROM AUTHOR]

Potassium antimonate was used to locate loosely bound calcium in the stigma and style of tobacco. The tobacco stigma is wet and covered by a thick layer of glycoprotein exudate at anthesis. The exudate contains abundant vesicles, which are densely labeled with calcium precipitates. When pollen grains arrive at the stigma, become hydrated, and as the pollen swells, Ca2+ precipitates accumulate at the aperture. Calcium precipitates that accumulate in pollen cytoplasm are initially concentrated within small vacuoles, but as germination proceeds these appear to fuse, forming prominent, densely labeled vesicles that preferentially accumulate near the proximal region of the growing tube. Although the stigma has abundant particles, few calcium precipitates are observed in the transmitting tissue from anthesis to 11 h after pollination. However, at 22 h after pollination, accumulation of calcium increases distally from the stigmatic interface with the transmitting tissue through the length of the style to the ovary. An examination of flowering plants with differing floral biology will be needed to understand the role of loosely bound calcium accumulation and its relationship to tissue-level changes in calcium uptake, maintenance of other calcium pools, including [Ca2+]cyt, and in pollen and style maturation during the progamic phase. [ABSTRACT FROM AUTHOR]

We give a new Hilbert's inequality with a best constant factor and some parameters. [ABSTRACT FROM AUTHOR]

We observed that curry leaf (Murraya koenigii) extract possesses the property to decrease blood cholesterol and blood glucose levels in diabetic ob/ob mice. Mice received daily intraperitoneal injections of 80 mg/kg curry leaf extract for 10 consecutive days. The extract significantly decreased blood cholesterol level from 277.6 ± 16.6 mg/d (day 0) to 182.0 ± 15.3 mg/d (day 10, p < 0.01 compared with the change in vehicle group). The extract also significantly decreased blood glucose level from 387.0 ± 15.6 mg/dl (day 0) to 214.0 ± 26.6 mg/dl (day 10, p < 0.01). In addition, body weight was reduced after extract treatment. Our data suggest that curry leaf may be proved to be of clinical importance in improving the management of high cholesterol level and type 2 diabetes. [ABSTRACT FROM AUTHOR]

Ginseng is a well-known medicinal plant used in traditional Oriental medicine. In recent decades, ginseng root has gained popularity as a dietary supplement in the United States. Ginseng has also been commonly used in Oriental medicine to treat diabetes-like conditions. The present review discusses the research on the anti-diabetic effects of ginseng and the possible mechanisms of its anti-diabetic actions. [ABSTRACT FROM AUTHOR]

Context: Shenxiang Suhe pill (SXSH), a traditional Chinese medicine, is clinically effective against coronary heart disease, but the mechanism of cardiac-protective function is unclear. Objective: We investigated the cardiac-protective mechanism of SXSH via modulating gut microbiota and metabolite profiles. Materials and methods: sprague-Dawley (SD) male rats were randomly divided into 6 groups (n = 8): sham, Model, SXSH (Low, 0.063 g/kg; Medium, 0.126 g/kg; High, 0.252 g/kg), and ato (atorvastatin, 20 mg/kg). Besides the sham group, rats were modelled with acute myocardial infarction (AMI) by ligating the anterior descending branch of the left coronary artery (laD). After 3, 7, 14 days' administration, ultrasound, H&E staining, serum enzymic assay, 16s rRNA sequencing were conducted to investigate the SXSH efficacy. Afterwards, five groups of rats: sham, Model, Model-ABX (AMI with antibiotics-feeding), SXSH (0.126 g/kg), SXSH-ABX were administrated for 14 days to evaluate the gut microbiota-dependent sXsh efficacy, and serum untargeted metabolomics test was performed. Results: 0.126 g/kg of sXsh intervention for 14 days increased ejection fraction (EF, 78.22%), fractional shortening (FS, 109.07%), and aortic valve flow velocities (AV, 21.62%), reduced lesion area, and decreased serum LDH (8.49%) and CK-MB (10.79%). Meanwhile, sXsh upregulated the abundance of Muribaculaceae (199.71%), Allobaculum (1744.09%), and downregulated Lactobacillus (65.51%). the cardiac-protective effect of sXsh was disrupted by antibiotics administration. SXSH altered serum metabolites levels, such as downregulation of 2-n-tetrahydrothiophenecarboxylic acid (THTC, 1.73%), and lysophosphatidylcholine (lysoPC, 4.61%). Discussion and conclusion: the cardiac-protective effect and suggested mechanism of sXsh could provide a theoretical basis for expanding its application in clinic. [ABSTRACT FROM AUTHOR]

Oil tankers carry large quantities of liquefied chemical cargoes that are flammable, explosive and/or toxic. Hence, a collision with a tanker that causes an oil spill poses a severe threat to the marine environment and human life. In order to quantify and analyze the risk factors of ship collision oil spill, this paper adopts a combination of knowledge element (KE) and dynamic Bayesian networks (DBN) to conduct an emergency scenario study based on the “scenario-response” model. Firstly, the key elements of “accident scenario state, human factors, emergency measures, and emergency goals” are selected to represent the accident. Then, the mechanism of accident evolution is analyzed according to the case, and DBN is used to build a scenario model of oil spills from tanker collisions. Finally, to verify the importance of human factors and the scientificity of emergency measures, the oil spill accident due to the collision between the two vessels known as MT “SANCHI” and MV “CF CRYSTAL” is used as an example for analysis. The accident model deduction results are in line with reality, and the research results help relevant decision makers to understand the deduction process of oil spills from tanker collisions, which is of great significance to enhance the safety of oil tanker shipping and marine environmental protection. [ABSTRACT FROM AUTHOR]

Rearranged during transfection (RET) rearrangement oncoprotein-mediated Ras/MAPK signaling cascade is constitutively activated in cancers. Here, we demonstrate a unique signal niche. The niche is a ternary complex based on the chimeric RET liquid-liquid phase separation. The complex comprises the rearranged kinase (RET fusion); the adaptor (GRB2), and the effector (SHC1). Together, they orchestrate the Ras/MAPK signal cascade, which is dependent on tyrosine kinase. CCDC6-RET fusion undergoes LLPS requiring its kinase domain and its fusion partner. The CCDC6-RET fusion LLPS promotes the autophosphorylation of RET fusion, with enhanced kinase activity, which is necessary for the formation of the signaling niche. Within the signal niche, the interactions among the constituent components are reinforced, and the signal transduction efficiency is amplified. The specific RET fusion-related signal niche elucidates the mechanism of the constitutive activation of the Ras/MAPK signaling pathway. Beyond just focusing on RET fusion itself, exploration of the ternary complex potentially unveils a promising avenue for devising therapeutic strategies aimed at treating RET fusion-driven diseases. [ABSTRACT FROM AUTHOR]

The mobility and the bioavailability of heavy metals in waste activated sludge were determined according to their total content and chemical speciation. A modified three-step sequential extraction procedure was used to determine the total content and metal speciation distribution pattern of various heavy metals (As, Cd, Cr, Cu, Ni, Pb, and Zn) pretreated at a temperature of 100 °C to 200 °C. It was found that the organics solubilization was enhanced at higher temperature, increased by 1.75, 183 and 3.03 folds over the soluble chemical oxygen demand (SCOD) at 100 C. The total contents of Cd, Pb and Zn exceeded the threshold value established in GB/T standard 23486 (2009), as a function of pH, due to the pollution from the local nonferrous metals industry. For most cases, the impacts of thermal pretreatment on the species distribution were limited and obscure. Cr was the only element showing a potential risk of metal mobilization, such that its residual fraction shifted towards oxidizable fraction at higher treatment temperature. The speciation distribution pattern of Ni, Cr, Cu, and Zn showed potential risks of contamination due to their bioavailability, mobility, or toxicity. [ABSTRACT FROM AUTHOR]

Purpose: Lifelong exercise is known to attenuate sarcopenia (age-associated reduction in muscle mass and function); however, the underlying molecular mechanisms remain unclear. As microRNAs are widely involved in the regulation of skeletal muscle growth and development, we aimed to evaluate the effects of lifelong regular exercise on age-related alterations in muscle microRNA expression profiles as well as on skeletal muscle atrophy, apoptosis, and mitochondria and autophagy dysfunction. Methods: Female 8-month-old Sprague-Dawley rats were divided into four groups; 1) 18 months of moderate-intensity continuous training (MICT) initiated at 8 months (adult-MICT, n = 12), 2) 8 months of MICT initiated at 18 months (presarcopenia-MICT, n = 12), 3) 8-month-old adult sedentary controls (adult-SED), and 4) 26-month-old aging sedentary controls (old- SED). Age skeletal muscles were then subjected to quantitative reverse transcription-polymerase chain reaction, Kyoto Encyclopedia of Genes and Genomes, immunoblotting, and miR-486 3' untranslated region luciferase reporter gene analyses. Results: Age-related loss of miR-486 expression was improved, skeletal muscle atrophy and apoptosis were downregulated, and mitochondrial activity and autophagy were upregulated in the adult-MICT group. Kyoto Encyclopedia of Genes and Genomes analysis revealed that the PI3K/Akt pathway was upregulated in adult-MICT rats compared with that in old-SED. In vitro analyses in rat skeletal muscle L6 cells further confirmed that miR-486 targets PTEN, not SAV1, thereby activating the PI3K/Akt pathway and indirectly inhibiting HIPPO signaling. Conclusions: Compared with presarcopenia-MICT rats, adult-MICT rats experienced greater beneficial effects regarding ameliorated age-related alterations in muscle miRNA expression profile, skeletal muscle atrophy, apoptosis, and mitochondria and autophagy dysfunction, which is potentially associated with the increased miR-486 expression and concomitant targeting of the PTEN/Akt signaling pathway. [ABSTRACT FROM AUTHOR]

Purpose RIOK1 has been proved to play an important role in cancer cell proliferation and migration in various types of cancers--such as colorectal and gastric cancers. However, the expression of RIOK1 in breast cancer (BC) and the relationship between RIOK1 expression and the development of BC are not well characterized. In this study, we assessed the expression of RIOK1 in BC and evaluated the mechanisms underlying its biological function in this disease context. Materials and Methods We used immunohistochemistry, western blot and quantitative real-time polymerase chain reaction to evaluate the expression of RIOK1 in BC patients. Then, knockdown or overexpression of RIOK1 were used to evaluate the effect on BC cells in vitro and in vivo. Finally, we predicted miR-204-5p could be a potential regulator of RIOK1. Results We found that the expression levels of RIOK1 were significantly higher in hormone receptor (HR)--negative BC patients and was associated with tumor grades (p=0.010) and p53 expression (p=0.008) and survival duration (p=0.011). Kaplan-Meier analysis suggested a tendency for the poor prognosis. In vitro, knockdown of RIOK1 could inhibit proliferation, invasion, and induced apoptosis in HR-negative BC cells and inhibited tumorigenesis in vivo, while overexpression of RIOK1 promoted HR-positive tumor progression. MiR-204-5p could regulate RIOK1 expression and be involved in BC progression. Conclusion These findings indicate that RIOK1 expression could be a biomarker of HR-negative BC, and it may serve as an effective prognostic indicator and promote BC progression. [ABSTRACT FROM AUTHOR]

Two non-canonical amino acids (ncAAs) with bio-orthogonal reactive groups, namely, p-azido-L-phenylalanine (p-AzF) and p-propargyloxy-L-phenylalanine (p-PaF), were genetically inserted into an aldo-keto reductase (AKR) and an alcohol dehydrogenase (ADH), respectively, at two preselected sites for each enzyme. The variants were expressed in the genome recoded bacterium Escherichia coli C321.ΔA. Supernatants of the individual cell lysates were subsequently mixed to produce orderly combi-crosslinked enzymes (O-CLEs) of AKR and ADH by co-polymerization of the two variants through their reactive bioorthogonal groups. The site-specific cross-linked enzymes (S-CLEs) and cross-linked enzyme aggregates (CLEAs) were produced using dibenzocycloocta-4a,6a-diene-5,11-diyne (DBA) and glutaraldehyde as the crosslinking agent, respectively. The catalytic efficiencies of the O-CLEs, S-CLEs and combi-CLEAs were determined using the water soluble dihydro-4, 4-dimethyl-2, 3-furandione as a surrogate substrate in aqueous solution at 37 °C. The O-CLEs exhibited the highest catalytic efficiency (Kcat/KM = 11.36 S-1 mM-1) that was 4.24 and 22.27 times that of S-CLEs and combi-CLEAs, respectively. In the asymmetric cascade synthesis of (R)-1-(2-chlorophenyl) ethanol the product yield after 14 h using the O-CLEs, S-CLEs and the combi-CLEAs was 93%, 55% and 16%, respectively. Moreover, high activities and selectivity (ee > 99.99%) were maintained at high substrate concentrations in prolonged operation. [ABSTRACT FROM AUTHOR]

The aroma indicator is an important factor in evaluating the quality and grade of black tea and is vital in preventing fraud and reducing financial losses. A rapid method for the characterization of Congou black tea is described using an electronic nose (EN) with grey wolf optimization (GWO) and chemometrics. First, the aroma qualities of the tea were determined by the EN for 700 samples of seven grades and converted into 10 characteristic values. The GWO algorithm was used to optimize the aroma indicators of the EN sensors. Discrimination models based upon the optimized odor sensor features and partial least squares discriminant analysis, k-nearest neighbor (KNN), extreme learning machine, and support vector machine were created to assess the quality of the samples. The results showed that the KNN model constructed with the five odor sensor response values optimized by the GWO algorithm performed best with an accuracy of 97.85%. The results demonstrate that the EN is suitable for the rapid assessment of the quality and grades of Congou black tea products. [ABSTRACT FROM AUTHOR]

Introduction: Postoperative pulmonary complications (PPCs) are prevalent in geriatric patients with hip fractures. Low oxygen level is one of the most important risk factors for PPCs. Prone position has been proven efficacy in improving oxygenation and delaying the progress of pulmonary diseases, especially in patients with acute respiratory distress syndrome induced by multiple etiologies. The application of awake prone position (APP) has also attracted widespread attention in recent years. A randomized controlled trial (RCT) will be carried out to measure the effect of postoperative APP in a population of geriatric patients undergoing hip fracture surgery. Methods: This is an RCT. Patients older than 65 years old admitted through the emergency department and diagnosed with an intertrochanteric or femoral neck fracture will be eligible for enrollment and assigned randomly to the control group with routine postoperative management of orthopedics or APP group with an additional prone position for the first three consecutive postoperative days (PODs). Patients receiving conservative treatment will not be eligible for enrollment. We will record the difference in the patient's room-air-breathing arterial partial pressure of oxygen (PaO2) values between the 4th POD (POD 4) and emergency visits, the morbidity of PPCs and other postoperative complications, and length of stay. The incidence of PPCs, readmission rates, and mortality rates will be followed up for 90 PODs. Discussion: We describe the protocol for a single-center RCT that will evaluate the efficacy of postoperative APP treatment in reducing pulmonary complications and improving oxygenation in geriatric patients with hip fractures. Ethics and dissemination: This protocol was approved by the independent ethics committee (IEC) for Clinical Research of Zhongda Hospital, Affiliated to Southeast University, and is registered on the Chinese Clinical Trial Registry. The findings of the trial will be disseminated through peer-reviewed journals. Ethics approval number: 2021ZDSYLL203-P01 Trial registration: ChiCTR ChiCTR2100049311. Registered on 29 July 2021. Trial status: Recruiting. Recruitment is expected to be completed in December 2024. [ABSTRACT FROM AUTHOR]

Microwaves have been widely used in the treatment of different materials. However, the existing adjustable power thermostatic reactors cannot be used to analyze materials characteristics under microwave effects. In this paper, a microwave thermostatic chemical reactor for processing liquid materials is proposed, by controlling the velocity of coolant based on PLC (programmable logic controller) in different liquid under different constant electric field intensity. A nonpolar coolant (Polydimethylsiloxane), which is completely microwave transparent, is employed to cool the liquid materials. Experiments are performed to measure the liquid temperature using optical fibers, the results show that the precision of temperature control is at the range of ±0.5 °C. Compared with the adjustable power thermostatic control system, the effect of electric field changes on material properties are avoided and it also can be used to detect the properties of liquid materials and special microwave effects. [ABSTRACT FROM AUTHOR]

A hydroponic experiment was conducted to investigate the effect of brassinosteroids (Br) and selenium (Se) on iron plaque (IP) formation and chromium (Cr) accumulation and uptake by Iris pseudacorus L. (yellow flag). Yellow flag seedlings (4 week old seedlings) were grown under 0.1 mg L-1 Br (24-epibrassinolide (Br24) or 28-homobrassinolide (Br28)) or 0.5 mg L-1 Se (Se(IV) or Se(VI)) for 2 weeks. Then seedlings with or without IP induction (60 mg Fe2+ L-1 for 3 days) were exposed to 5 mg L-1 hexavalent chromium [Cr(VI)] for 1 week. The results showed that Cr reduced Fe accumulation and uptake by yellow flag with or without IP; however, this effect was significantly neutralized by Br, but not by Se. IP significantly enhanced Cr accumulation in DCB extract and the whole yellow flag seedling, and increased Cr content by 36%. Br24 and Br28 significantly enhanced Cr accumulation and uptake by yellow flag and increased Cr enrichment by 36 and 51% in the absence of IP, and 7 and 21% in the presence of IP, respectively. Se(IV) markedly improved Cr accumulation in the root, but Cr accumulation and uptake in the shoot and DCB extract were not affected by Se(IV) and Se(VI). Our study suggests that Br24 and Br28 can alleviate Fe loss caused by Cr stress and increase Cr accumulation and uptake by yellow flag seedlings. [ABSTRACT FROM AUTHOR]

We study the problem of morphing two polygons of building footprints at two different scales. This problem frequently occurs during the continuous zooming of interactive maps. The ground plan of a building footprint on a map has orthogonal characteristics, but traditional morphing methods cannot preserve these geographic characteristics at intermediate scales. We attempt to address this issue by presenting a turning angle function-based morphing model (TAFBM) that can generate polygons at an intermediate scale with an identical turning angle for each side. Thus, the orthogonal characteristics can be preserved during the entire interpolation. A case study demonstrates that the model yields good results when applied to data from a building map at various scales. During the continuous generalization, the orthogonal characteristics and their relationships with the spatial direction and topology are well preserved. [ABSTRACT FROM AUTHOR]

Elemene is a second-line broad-spectrum anti-tumour drug that has been used in China for more than two decades. However, its main anti-tumour ingredient, β-elemene, has disadvantages, including excessive lipophilicity and relatively weak anti-tumour efficacy. To improve the anti-tumour activity of β-elemene, based on its minor molecular weight character, we introduced furoxan nitric oxide (NO) donors into the β-elemene structure and designed six series of new generation β-elemene NO donor hybrids. The synthesised compounds could effectively release NO in vitro, displayed significant anti-proliferative effects on U87MG, NCI-H520, and SW620 cell lines. In the orthotopic glioma model, compound Id significantly and continuously suppressed the growth of gliomas in nude mice, and the brain glioma of the treatment group was markedly inhibited (>90%). In short, the structural fusion design of NO donor and β-elemene is a feasible strategy to improve the in vivo anti-tumour activity of β-elemene. [ABSTRACT FROM AUTHOR]

A series of novel N-alkyl-N-hydroxyl carboximates derived from β-elemene were fortuitously discovered. Most of them showed more potent anti-proliferative activities than their lead compound β-elemene (1). Notably, compound 11i exhibited significant inhibitory effects on the proliferation of three lung cell lines (H1975, A549 and H460) and several other tumour cell lines (H1299, U87MG, MV4-11, and SU-DHL-2). Preliminary mechanistic studies revealed that compound 11i could significantly induce cell apoptosis. Further in vivo study in the H460 xenograft mouse model validated the anti-tumour activities of 11i with a greater tumour growth inhibition (TGI, 68.3%) than β-elemene and SAHA (50.1% and 55.9% respectively) at 60mg/kg ip dosing, without obvious body weight loss and toxicity. Thus, such N-alkyl-N-hydroxyl carboximate class of compounds exemplified as 11i demonstrated potent anticancer activities both in vitro and in vivo, and should warrant further investigation for potential anticancer therapy. [ABSTRACT FROM AUTHOR]

A high time resolution synchronous sampling method al ong with determination of stable carbon isotopes of gaseous water-soluble organic carbon (WSOCg) and particulate water-soluble organic carbon (WSOCp) was realized in this research through equipment modification and method improvement. It was found that WSOCg has significant higher concentration than WSOCp and a more depleted δ13C. Both concentrations of WSOCp and WSOCg have the seasonal variation characteristics of high in winter (WSOCp=15.7±3.9µg/m³; WSOCg=42.4±6.0µg/m³) and low in summer (WSOCp=5.9±1.8µg/m³; WSOCg=25.2±5.2µg/m³), with greater increase in WSOCp (167%) than that in WSOCg (68%). During wintertime, WSOCp and WSOCg had similar daily variation characteristics of concentration, and opposite daily variation characteristics of δ13C. WSOCp had a bimodal distribution with obvious low value at sunrise and sunset, while δ13C WSOCp had a unimodal distribution with low in daytime (-24.6±1.1‰) and high in nighttime (- 22.3±1.7‰). WSOCg and δ13C-WSOCg had same distribution with high in daytime and (49.3±8.8µg/m³; -27.9±1.1‰) low in nighttime (38.3±4.6µg/m³; -29.9±0.4‰). Combining the δ13C variation characteristics with the synchronous observation results of meteorological conditions, gaseous precursor pollutants, gaseous oxidants, gaseous acids and fine particle components, the restriction factors of WSOC gas-particle distribution mechanism were discussed. The presence of radiation rather than its intensity decided whether generations process of WSOCp and WSOCg are divided, for δ13C-WSOC of two phases showed significant correlation only during daytime. Meteorological conditions, gaseous precursor pollutants, gaseous oxidants and gaseous acids restrict the gas particle distribution of WSOC by affecting the aging process of WSOCp and WSOCg, gas particle conversion ratio of semi-volatile organic compounds (SVOC) and the gas phase and liquid phase generation ratio of WSOCp. At the same time, the gas-particle distribution process of WSOC is strongly related to the formation of secondary inorganic ions (nitrate, sulfate, ammonium), and the gas-particle distribution between gaseous nitrous acid and nitrite. [ABSTRACT FROM AUTHOR]

Leaf and tuber extracts of Curcuma wenyujin contain a mixture of curcuminoids. However, the curcuminoid constituents and their molecular mechanisms are poorly understood, and the relevant curcumin synthases remain unclear. In this study, we comprehensively compared the metabolite profiles of the leaf and tuber tissues of C. wenyujin. A total of 11 curcuminoid metabolites were identified and exhibited differentially changed contents in the leaf and tuber tissues. An integrated analysis of metabolomic and transcriptomic data revealed the proposed biosynthesis pathway of curcuminoid. Two candidate type III polyketide synthases (PKSs) were identified in the metabolically engineering yeasts, indicating that CwPKS1 and CwPKS2 maintained substrate and product specificities. Especially, CwPKS1 is the first type III PKS identified to synthesize hydrogenated derivatives of curcuminoid, dihydrocurcumin and tetrehydrocurcumin. Interestingly, the substitution of the glycine at position 219 with aspartic acid (G219D mutant) resulted in the complete inactivation of CwPKS1. Our results provide the first comparative metabolome analysis of C. wenyujin and functionally identified type III PKSs, giving valuable information for curcuminoids biosynthesis. [ABSTRACT FROM AUTHOR]

Background: Bacterial surface display technique enables the exogenous proteins or polypeptides displayed on the bacterial surface, while maintaining their relatively independent spatial structures and biological activities. The technique makes recombinant bacteria possess the expectant functions, subsequently, directly used for many applications. Many proteins could be used to achieve bacterial surface display, among them, autotransporter, a member of the type V secretion system of gram-negative bacteria, has been extensively studied because of its modular structure and apparent simplicity. However, autotransporter has not been widely used at present due to lack of a convenient genetic vector system. With our recently characterized autotransporter BrkA (Bordetella serum-resistance killing protein A) from Bordetella pertussis, we are aiming to develop a new autotransporter-based surface display system for potential wide application. Results: Here, we construct a bacterial surface display system named as BrkAutoDisplay, based on the structure of autotransporter BrkA. BrkAutoDisplay is a convenient system to host exogenous genes. In our test, this system is good to efficiently display various proteins on the outer membrane surface of Escherichia coli, including green fluorescent protein (GFP), various enzymes and single chain antibody. Moreover, the displayed GFP possesses green fluorescence, the enzymes CotA, EstPc and PalA exhibit catalytic activity 0.12, 6.88 and 0.32 mU (per 5.2 x 108 living bacteria cells) respectively, and the single chain antibody fragment (scFv) can bind with its antigen strongly. Finally, we showed that C41(DE3) is a good strain of E. coli for the successful functionality of BrkAutoDisplay. Conclusions: We designed a new bacterial display system called as BrkAutoDisplay and displayed various exogenous proteins on E. coli surface. Our results indicate that BrkAutoDisplay system is worthy of further study for industrial applications. [ABSTRACT FROM AUTHOR]

High-strength steel investigation is focused on the production of low carbon microalloying steel, particularly in the enhancement of steel strength through microstructure control, which is an urgent problem nowadays. This paper investigates the effect of various thermal mechanical control processing parameter on the properties and microstructures of Mn-Ti low carbon steels. The steel exhibited yield strength of 920 to 1069 MPa, elongation of approximately 10%, and impact absorbed energy between 16.7 and 45.3 J. At constant coiling temperature, more lath-shaped carbonless ferrites, retained austenitic films with finer width, and island-like twin martensites were generated. Strength and yield ratio increased with increase in finishing rolling temperature, but impact absorbed energy and total elongation decreased. When the finishing rolling temperature and coiling temperature were 860 and 220°C, respectively, the steel exhibited the highest strength and yield ratio but the lowest plasticity and toughness. At increased coiling temperature and unchanged finishing rolling temperature, more lath-shaped ferrites with greater width were generated and gradually changed from carbonless to low-bainite because of precipitations inside them. The width of the retained austenite increased with increase in coiling temperature. Thus, the strength and yield ratio decreased, but plasticity and impact toughness increased. [ABSTRACT FROM AUTHOR]

Lysine-specific demethylase 6A (KDM6A), also named UTX, is frequently mutated in bladder cancer (BCa). Although known as a tumor suppressor, KDM6A's therapeutic potential in the metastasis of BCa remains elusive. It also remains difficult to fulfill the effective up-regulation of KDM6A levels in bladder tumor tissues in situ to verify its potential in treating BCa metastasis. Here, we report a mucoadhesive messenger RNA (mRNA) nanoparticle (NP) strategy for the intravesical delivery of KDM6A-mRNA in mice bearing orthotopic Kdm6a-null BCa and show evidence of KDM6A's therapeutic potential in inhibiting the metastasis of BCa. Through this mucoadhesive mRNA NP strategy, the exposure of KDM6A-mRNA to the in situ BCa tumors can be greatly prolonged for effective expression, and the penetration can be also enhanced by adhering to the bladder for sustained delivery. This mRNA NP strategy is also demonstrated to be effective for combination cancer therapy with other clinically approved drugs (e.g., elemene), which could further enhance therapeutic outcomes. Our findings not only report intravesical delivery of mRNA via a mucoadhesive mRNA NP strategy but also provide the proof-of-concept for the usefulness of these mRNA NPs as tools in both mechanistic understanding and translational study of bladder-related diseases. [ABSTRACT FROM AUTHOR]

This study attempted to measure the total polyphenols contents in Fuzhuan tea by near-infrared (NIR) spectroscopy coupled with an appropriate multivariate calibration method. Partial least squares (PLS), synergy interval PLS (si-PLS), and genetic algorithm-based PLS (ga-PLS) were carried out comparatively to calibrate regression models. The root mean square error of prediction (RMSEP), determination coefficient (Rp2), and P-value between the true and predicted values of prediction set were used to evaluate the performance of the final model. The ga-PLS model showed the best performance compared with the PLS and si-PLS models. The optimal model obtained Rp2 = 0.9996 and RMSEP = 0.0488 for the prediction set using only 37 spectral data points. No significant difference was observed between the true and predicted tea polyphenol contents in the prediction set (P > 0.05). NIR spectroscopy together with the ga-PLS algorithm can be used to rapidly predict the total polyphenol contents in Fuzhuan tea. [ABSTRACT FROM AUTHOR]

This study proposed a comprehensive evaluation system to incorporate the contribution of both numerical simulation and statistical decision theory in ventilation performance assessment. A high-resolution model based on the finite volume approach was established to analyze the influence of rotation angles (i.e., side vent flip angle and roof vent flip angle) of the rack-and-pinion ventilated structure on the greenhouse microclimate. The water circulating system and tomato seeding canopies were considered. Heat removal efficiency and mean age of air were employed as quantitative attributes to reflect the internal thermal environment and the airflow organization in the sliding cover solar greenhouse. The simulation model was verified with the temperature profile measured and the average relative error was 1.74%. The results demonstrate that the rotating angles of ventilation schemes have a substantial impact on the microclimate and inhomogeneity of the tomato seeding canopies. The results suggest the average velocity and its inhomogeneity are the crucial predictors, and their entropy weight values are 0.231 and 0.218, respectively. The relative degree of membership of the side vent flip angle of 45° is 36% and 97% higher than that of the side vent flip angle of 35° and the side vent flip angle of 25°, respectively. This study can provide a reference to evaluate the ventilated strategies of the sliding cover solar greenhouse for the regional and central government. [ABSTRACT FROM AUTHOR]

The coronavirus disease 19 (COVID-19) caused by the novel coronavirus known as SARS-CoV-2 has caused a global public health crisis. As of 7 January 2021, 87,640,402 confirmed cases and 1,891,692 mortalities have been reported worldwide. Studies focusing on the epidemiological and clinical characteristics of COVID-19 patients have suggested a dysregulated immune response characterized by lymphopenia and cytokine storm in these patients. The exaggerated immune response induced by the cytokine storm causes septic shock, acute respiratory distress syndrome (ARDS), and/or multiple organs failure, which increases the fatality rate of patients with SARS-CoV -2 infection. Herein, we review the recent research progress on epidemiology, clinical features, and system pathology in COVID-19. Moreover, we summarized the recent therapeutic strategies, which are either approved, under clinical trial, and/or under investigation by the local or global health authorities. We assume that treatments should focus on the use of antiviral drugs in combination with immunomodulators as well as treatment of the underlying comorbidities. [ABSTRACT FROM AUTHOR]

Objective: In this study, we aimed to develop an amino-terminal fragment (ATF) peptide-targeted liposome carrying β-elemene (ATF24-PEG-Lipo-β-E) for targeted delivery into urokinase plasminogen activator receptor-overexpressing bladder cancer cells combined with cisplatin (DDP) for bladder cancer treatment. Methods: The liposomes were prepared by ethanol injection and high-pressure microjet homogenization. The liposomes were characterized, and the drug content, entrapment efficiency, and in vitro release were studied. The targeting efficiency was investigated using confocal microscopy, ultra-fast liquid chromatography, and an orthotopic bladder cancer model. The effects of ATF24-PEG-Lipo- β-E combined with DDP on cell viability and proliferation were evaluated by a Cell Counting Kit-8 (CCK-8) assay, a colony formation assay, and cell apoptosis and cell cycle analyses. The anticancer effects were evaluated in a KU-19-19 bladder cancer xenograft model. Results: ATF24-PEG-Lipo-β-E had small and uniform sizes (~79 nm), high drug loading capacity (~5.24 mg/mL), high entrapment efficiency (98.37 ± 0.95%), and exhibited sustained drug release behavior. ATF24-PEG-Lipo-β-E had better targeting efficiency and higher cytotoxicity than polyethylene glycol (PEG)ylated β-elemene liposomes (PEG-Lipo-β-E). DDP, combined with ATF24-PEGLipo- β-E, exerted a synergistic effect on cellular apoptosis and cell arrest at the G2/M phase, and these effects were dependent on the caspase-dependent pathway and Cdc25C/Cdc2/cyclin B1 pathways. Furthermore, the in vivo antitumor activity showed that the targeted liposomes effectively inhibited the growth of tumors, using the combined strategy. Conclusions: The present study provided an effective strategy for the targeted delivery of β-elemene (β-E) to bladder cancer, and a combined strategy for bladder cancer treatment. [ABSTRACT FROM AUTHOR]

In the recent 60 years, accompanied by the remarkable decline of its sediment into the sea, The Yellow River Delta has been experiencing severe erosion. Based on this, this paper attempts to propose a new type of open breakwater with good wave-dissipating performance, which can be used to protect the Yellow River Delta from extensive erosion (Wang et al., 2016a). In this study, a numerical model for the interactions between waves and plate-type open breakwaters are constructed using the finite volume method, and their correctness is validated by experimental results. The numerical results show that, by comprehensively considering Kt, Kr, the double arc-shaped plate-type (DAPT) open breakwater is found to exhibit the highest wave-dissipating performance among the double flat plate-type (DFPT), single arc-shaped plate-type (SAPT) open breakwater and double arc-shaped plate-type (DAPT) open breakwater. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to develop a new polyethylene glycol (PEG)ylated β-elemene liposome (PEG-Lipo-β-E) and evaluate its characterization, pharmacokinetics, antitumor effects and safety in vitro and in vivo. Methods: The liposomes were prepared by ethanol injection and high-pressure micro-jet homogenization. Characterization of the liposomes was conducted, and drug content, entrapment efficiency (EE), in vitro release and stability were studied by ultra-fast liquid chromatography (UFLC) and a liquid surface method. Blood was drawn from rats to establish the pharmacokinetic parameters. The anticancer effect was evaluated in a KU-19-19 bladder cancer xenograft model. Histological analyses were performed to evaluate safety. Results: The PEG-Lipo-β-E showed good stability and was characterized as 83.31 ± 0.181 nm in size, 0.279 ± 0.004 in polydispersity index (PDI), -21.4 ± 1.06 mV in zeta potential, 6.65 ± 0.02 in pH, 5.024 ± 0.107 mg/mL in β-elemene (β-E) content, and 95.53 ± 1.712% in average EE. The Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) indicated the formation of PEG-Lipo-β-E. Compared to elemene injection, PEG-Lipo-β-E demonstrated a 1.75-fold decrease in clearance, a 1.62-fold increase in half-life, and a 1.76-fold increase in area under the concentration-time curves (AUCs) from 0 hour to 1.5 hours (P < 0.05). PEG-Lipo-β-E also showed an enhanced anticancer effect in vivo. Histological analyses showed that there was no evidence of toxicity to the heart, kidney, liver, lung or spleen. Conclusions: The present study demonstrates PEG-Lipo-β-E as a new formulation with ease of preparation, high EE, good stability, improved bioavailability and antitumor effects. [ABSTRACT FROM AUTHOR]

The self-diffusion problem of Brownian particles under the constraint of quasi-one-dimensional (q1D) channel has raised wide concern. The hydrodynamic interaction (HI) plays an important role in many practical problems and two-body interactions remain dominant under q1D constraint. We measure the diffusion coefficient of individual ellipsoid when two ellipsoidal particles are close to each other by video-microscopy measurement. Meanwhile, we obtain the numerical simulation results of diffusion coefficient using finite element software. We find that the self-diffusion coefficient of the ellipsoid decreases exponentially with the decrease of their mutual distance X when , where X0 is the maximum distance of the ellipsoids to maintain their mutual influence, X0 and the variation rate are related to the aspect ratio p=a/b. The mean squared displacement (MSD) of the ellipsoids indicates that the self-diffusion appears as a crossover region, in which the diffusion coefficient increases as the time increases in the intermediate time regime, which is proven to be caused by the spatial variations affected by the hydrodynamic interactions. These findings indicate that hydrodynamic interaction can significantly affect the self-diffusion behavior of adjacent particles and has important implications to the research of microfluidic problems in blood vessels and bones, drug delivery, and lab-on-chip. [ABSTRACT FROM AUTHOR]

In this paper, we adopted thermally stable HfOxNy as gate dielectric for TiN/HfOxNy/AlGaN/GaN heterostructure field-effect transistors (HFETs) application. It demonstrated that the surface morphologies, composition, and optical properties of the HfOxNy films were dependent on oxygen flow rate in the O2/N2/Ar mixture sputtering ambient. The obtained metal–oxide–semiconductor heterostructure field-effect transistors by depositing HfO2 and HfOxNy dielectric at different oxygen flow rates possessed a small hysteresis and a low leakage current. After post deposition annealing at 900 °C, the device using HfOxNy dielectric operated normally with good pinch-off characteristics, while obvious degradation are observed for the HfO2 gated one at 600 °C. This result shows that the HfOxNy dielectric is a promising candidate for the self-aligned gate process. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented about an investigation of spargana infection in frogs, the second intermediate host of Spirometra, in Guangdong, China.

The four-component intramembrane protease γ-secretase is intricately linked to the development of Alzheimer's disease. Despite recent structural advances, the transmembrane segments (TMs) of γ-secretase remain to be specifically assigned. Here we report a 3D structure of human γ-secretase at 4.32-Å resolution, determined by single-particle, electron cryomicroscopy in the presence of digitonin and with a T4 lysozyme fused to the amino terminus of presenilin 1 (PS1). The overall structure of this human γ-secretase is very similar to that of wild-type γ-secretase determined in the presence of amphipols. The 20 TMs are unambiguously assigned to the four components, revealing principles of subunit assembly. Within the transmembrane region, PS1 is centrally located, with its amino-terminal fragment (NTF) packing against Pen-2 and its carboxyl- terminal fragment (CTF) interacting with Aph-1. The only TM of nicastrin associates with Aph-1 at the thick end of the TM horseshoe, and the extracellular domain of nicastrin directly binds Pen-2 at the thin end. TM6 and TM7 in PS1, which harbor the catalytic aspartate residues, are located on the convex side of the TM horseshoe. This structure serves as an important framework for understanding the function and mechanism of γ-secretase. [ABSTRACT FROM AUTHOR]

Early trials have demonstrated great potential for the use of duckweed (family Lemnaceae) as the next generation of energy plants for the production of biofuels. Achieving this technological advance demands research to develop novel bioengineering microorganisms that can ferment duckweed feedstock to produce higher alcohols. In this study, we used relevant genes to transfer five metabolic pathways of isoleucine, leucine and valine from the yeast Saccharomyces cerevisiae into the bioengineered microorganism Corynebacterium crenatum. Experimental results showed that the bioengineered strain was able to produce 1026.61 mg/L of 2-methyl-1-butanol by fermenting glucose, compared to 981.79 mg/L from the acid hydrolysates of duckweed. The highest isobutanol yields achieved were 1264.63 mg/L from glucose and 1154.83 mg/L from duckweed, and the corresponding highest yields of 3-methyl-1-butanol were 748.35 and 684.79 mg/L. Our findings demonstrate the feasibility of using bioengineered C. crenatum as a platform to construct a bacterial strain that is capable of producing higher alcohols. We have also shown the promise of using duckweed as the basis for developing higher alcohols, illustrating that this group of plants represents an ideal fermentation substrate that can be considered the next generation of alternative energy feedstocks. [ABSTRACT FROM AUTHOR]

Arginine-Glycine-Aspartic (RGD), is the specific recognition site of integrins with theirs ligands, and regulates cell-cell and cell-extracellular matrix interactions. The RGD motif can be combined with integrins overexpressed on the tumor neovasculature and tumor cells with a certain affinity, becoming the new target for imaging agents, and drugs, and gene delivery for tumor treatment. Further, RGD as a biomimetic peptide can also promote cell adherence to the matrix, prevent cell apoptosis and accelerate new tissue regeneration. Functionalizing material surfaces with RGD can improve cell/biomaterial interactions, which facilitates the generation of tissue-engineered constructs. This paper reviews the main functions and advantages of RGD, describes the applications of RGD in imaging agents, drugs, gene delivery for tumor therapy, and highlights the role of RGD in promoting the development of tissue engineering (bone regeneration, cornea repair, artificial neovascularization) in recent years. [ABSTRACT FROM AUTHOR]

High-density polyethylene (HDPE)/Mg2 Al--layered double hydroxide (Mg2 Al--LDH) nanocomposites with an ethylene-acrylic acid random copolymer (EAA)/Mg2 Al--LDH master batch were prepared by melt-mixing. The structure of the nanocomposites was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results demonstrate the formation of the nanocomposites with exfoliated/intercalated layered double hydroxides well distributed in the HDPE matrix. The nonisothermal crystallization behaviour of master batch-based HDPE nanocomposites was studied by using differential scanning calorimetry (DSC). The crystallization behaviour of HDPE/Mg2 Al--LDH nanocomposites was well defined by the Avrami analysis and Jeziorny method, as well as the combined Avrami and Ozawa analysis (MO's model). The results reveal that a very small amount of Mg2 Al--LDH (1%) accelerates the crystallization process in comparison with the neat HDPE, and the high crystallization rate is attributed to the nucleating effect of the exfoliated nanoparticles. Overall, the exfoliated Mg2 Al--LDH particles act as the nucleating agent, and therefore distinctly change the type of nucleation, growth and geometry of HDPE crystals. [ABSTRACT FROM AUTHOR]