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Background: No consensus has been concluded with regarding to the scope of lymph node (LN) dissection for Siewert type II and III adenocarcinoma of the esophagogastric junction (AEG). This study aimed to explore risk factors for lower perigastric LN (LPLN) metastases (including no. 4d, 5, 6, and 12a LN stations) and analyze the indications for LPLN dissection. Methods: In total, 302 consecutive patients with Siewert type II and III AEG who underwent total gastrectomy (TG) were enrolled. The logistic regression model was used to perform uni- and multivariate analyses of risk factors for LPLN metastases. Kaplan–Meier curves were used for survival analysis, and log-rank tests were used for group comparisons. Basing on the guidelines of Japanese Gastric Cancer Association, the LN metastases (LNM) as well as the efficiency index (EI) of each LN station was further evaluated. Results: The independent risk factors for LPLN metastases in patients with Siewert type II and III AEG were distance from the esophagogastric junction (EGJ) to the distal end of the tumor (> 4.0 cm), preoperative carcinoembryonic antigen (CEA) ( +), pT4 stage, and HER-2 ( +). LPLN metastases was an independent risk factor for overall survival following TG. The LNM and EI of LPLN were 8.6% and 2.31%, respectively. The LNM of LPLN > 10% under the stratification of the distance from the EGJ to the distal end of the tumor (> 4.0 cm), pT4, preoperative CEA ( +), and HER-2 ( +) exhibited EI values of 3.55%, 2.09%, 2.51%, and 3.64%, respectively. Conclusions: LPLN metastases was a malignant factor for the prognosis of patients with Siewert type II and III AEG. For patients with preoperative CEA ( +), pT4 stage, HER-2 ( +), and the distance from the EGJ to the distal end of the tumor (> 4.0 cm), TG with LPLN dissection is prioritized for clinical recommendation.

An efficient Ni-catalyzed four-component 1,4-carbocarbonylation of 1,3-enynes with activated alkyl halides and arylboronic acids under atmospheric pressure of CO is presented. By tuning the electronic and steric effects of alkyl radicals, both electron-rich and electron-deficient 1,3-enynes were compatible with this cascade. This protocol features mild conditions, broad substrate scope, excellent functional group compatibility and facile gram-scale synthesis, providing a practical approach to the quaternary carbon center-containing allenyl ketones. Mechanistic study revealed that the acyl-NiIIspecies plays an important role in both the coupling and the alkyl radical generation processes.

Fluorinated compounds have found widespread applications in pharmaceuticals, agrochemicals, and materials science. Precise construction of α-difluoromethylene ether (CF2–O) moiety in organic molecules is of high demand. Herein, a visible light-promoted reaction protocol for the synthesis of α-difluoromethylene ether from gem-difluorocyclopropane is described. The key ring-opening step is induced by hyperconjugative interaction of cyclopropane with photo-oxidized aromatic rings. This reaction is easy scale-up, and the products bearing a synthetic handle enable their further manipulation.

Natural seawater is a kind of sustainable source to provide uranium in the future. Uranium extraction from seawater faces great challenges, including weak mechanical strength, poor selectivity and severe fouling. In this paper, based on the principle of additive manufacturing technology, poly(amidoxime)-loaded hollow spheres (3D-PAO) with multilayer skeleton structures were prepared via 3D printing method. The adsorption process matched the Langmuir isotherm model better and the calculated maximum U(VI) uptake on 3D-PAO was 78.01 mg/g. In addition, 3D-PAO presented high selectivity to U(VI) against other coexisted metal ions. In addition, the regeneration efficiency of 3D-PAO reached a high value of 71.63% after six-time regeneration, and 3D-PAO still displayed great reusability with the coexistence of different oils. This work provided a feasible strategy to improve the selectivity, mechanical strength and antifouling performance of uranium adsorbents and opens a new avenue for oceanic uranium extraction.

Microplastic (MP) contamination is a serious global environmental problem. Plastic contamination has attracted extensive attention during the past decades. While physiochemical weathering may influence the properties of MPs, biodegradation by microorganisms could ultimately mineralize plastics into CO2. Compared to the well-studied marine ecosystems, the MP biodegradation process in riverine ecosystems, however, is less understood. The current study focuses on the MP biodegradation in one of the world’s most plastic contaminated rivers, Pearl River, using micropolyethylene (mPE) as a model substrate. Mineralization of 13C-labeled mPE into 13CO2provided direct evidence of mPE biodegradation by indigenous microorganisms. Several Actinobacteriotagenera were identified as putative mPE degraders. Furthermore, two Mycobacteriaceaeisolates related to the putative mPE degraders, Mycobacteriumsp. mPE3 and Nocardiasp. mPE12, were retrieved, and their ability to mineralize 13C-mPE into 13CO2was confirmed. Pangenomic analysis reveals that the genes related to the proposed mPE biodegradation pathway are shared by members of Mycobacteriaceae. While both Mycobacteriumand Nocardiaare known for their pathogenicity, these populations on the plastisphere in this study were likely nonpathogenic as they lacked virulence factors. The current study provided direct evidence for MP mineralization by indigenous biodegraders and predicted their biodegradation pathway, which may be harnessed to improve bioremediation of MPs in urban rivers.

ABSTRACTLong non-coding RNAs (lncRNAs) have been demonstrated to influence the chemoresistance of colorectal cancer (CRC). Therefore, the study is designed to investigate the regulatory function and mechanism of Taurine up-regulated gene 1 (TUG1) in the cisplatin resistance of CRC. qRT-PCR checked the expressions of TUG1, Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2), and miR-195-5p in CRC tissues and cells. The TUG1 or miR-195-5p overexpression model was engineered in CRC cells, followed by treatment with DDP or the autophagy inhibitor (Chloroquine, CQ). CCK8 (Cell Counting Kit-8) and the colony formation experiment monitored cell proliferation. Flow cytometry examined apoptosis, Transwell tracked migration and invasion, and Western blot ascertained the protein profiles of autophagy proteins (LC3I/LC3II and Beclin1) and the HDGF/DDX5/β-catenin pathway. Dual-luciferase gene reporter assay and RNA immunoprecipitation confirmed the binding correlation between TUG1 and miR-195-5p and between miR-195-5p and HDGF. Furthermore, in-vivoexperiments in nude mice probed the function and mechanism of IGF2BP2 in CRC cell growth. The profiles of TUG1 and IGF2BP2 were elevated in CRC tissues, and IGF2BP2 enhanced TUG1’s expression in CRC cells. TUG1 activated autophagy to facilitate CRC cells’ resistance to DDP. TUG1 targets miR-195-5p, and miR-195-5p targets HDGF. Overexpression of miR-195-5p abated the cancer-promoting function of TUG1 and curbed the profile of the HDGF/DDX5/β-catenin axis. TUG1 stabilized by IGF2BP2 boosted CRC cell proliferation, migration, migration, and autophagy via the miR-195-5p/HDGF/DDX5/β-catenin axis, hence enhancing CRC cell’s resistance to DDP.

In this study, we present a novel approach to fabricate a granular ceramic material utilizing a composite of nano zero-valent iron (nZVI), carbon, and kaolin. The optimal mass ratio of the prepared material was kaolin, nZVI, activated carbon, and appropriate additives = 40%:40%:10%:10%. The resulting composite demonstrated microelectrolysis effects, enhancing its reactivity for pollutant removal. Activated carbon within the composite significantly increased the interlayer spacing of kaolin, and improved material performance. Furthermore, the addition of activated carbon proved effective in preventing the agglomeration of nZVI, and ensuring a stable and efficient pollutant removal process. The results of 40-day column experiments showed that nano iron-carbon-kaolin micro-electrolysis particles (NIMP) consistently demonstrated stable trichloroethane (TCE) removal with an average removal rate of 88.15 ± 3.24%. Batch experiments confirmed that the synthesized material can achieve complete dechlorination of TCE, which was consistent with density functional theory calculations. The developed material exhibited a robust soil structure and high reactivity for pollutant reduction, making it a promising substrate filler for efficiently degrading refractory organic pollutants. It holds great potential for applications in areas such as water treatment and soil remediation.

Vanadium (V) is an important metal with critical industrial and medical applications. Elevated V contamination, however, can be a threat to the environment and human health. Microorganisms can reduce the more toxic and mobile VVto the less toxic and immobile VIV, which could be a detoxification and energy metabolism strategy adopted by V-reducing bacteria (VRB). The limited understanding of microbial responses to V contamination and the mechanisms for VVreduction, however, hamper our capability to attenuate V contamination. This study focused on determining the microbial responses to elevated V concentration and the mechanisms of VVreduction in V tailings. The bacterial communities were characterized and compared between the V tailings and the less contaminated adjacent mineral soils. Further, VV-reducing enrichments indicated that bacteria associated with Polaromonas, a genus belonging to the family Burkholderiaceae, were potentially responsible for VVreduction. Retrieved metagenome-assembled genomes (MAGs) suggested that the Polaromonasspp. encoded genes (cymA, omcA, and narG) were responsible for VVreduction. Additionally, Polaromonasspp. was metabolically versatile and could use both organic and inorganic electron donors. The metabolic versatility of Polaromonasspp. may be important for its ability to flourish in the V tailings.

The widespread application of sewage sludge produced from wastewater treatment plants for agricultural use has been regarded as a primary source of microplastics (MPs) into soils. However, little is known regarding MPs in sludge-based fertilizers and their relevant fate in soils as being applied in agriculture. We comprehensively investigated the abundance, polymer size, type, and morphology of MPs in dewatered sludge, sewage sludge composts, sludge-based fertilizer-amended soils, and earthworms by stereoscopy and micro Fourier transform infrared (μ-FTIR) spectrometry methods. The results clearly showed that the quantity of MPs in soils exhibited a close correlation with the application rate of sludge-based fertilizers. The total abundances of MPs were 545.9 and 87.6 items/kg in soils after annual amendment with 30 (field A) and 15 t/ha (field B) of sludge composts, which is significantly higher than that without compost application (field C, 5.0 items/kg). Correspondingly, MPs were found in earthworms with low quantities of 1.8 and 0.4 items/individual in fields A and B, respectively, while no MP was detected in field C. We speculate that sludge composts may act as a vehicle of MPs into soils and then enter soil biota and in turn influence the spread of MPs in the environment.

Nitrogen‐rich compounds involving the cyclo‐pentazole anion (cyclo‐N5−) have attracted extensive attention due to higher energy release and environmental friendliness than traditional high energy density materials (HEDMs). However, the synthesis of stable HEDMs with cyclo‐N5−is still a challenge. In this study, the effect of nine solvents on the geometrical and electronic structures and solvation energies of Zn(N5)2, one of the recently synthesized nitrogen‐rich compounds, was studied using the density functional theory and the polarized continuum model. The results indicated an increase in the stability of Zn(N5)2in the solution phase compared to the vacuum phase, and the stability of Zn(N5)2increases with increasing dielectric constants. The energy gap of frontier molecular orbitals and the absolute value of total energy in water are the largest, revealing that Zn(N5)2is more stable in water than in other solvents. To understand the stabilization mechanism of Zn(N5)2by water, further studies were performed with the natural bond orbital (NBO) analysis and the quantum theory of atoms in molecules (QTAIM) analysis using the explicit solvent model. The charge transfer and the hydrogen bonds are observed between Zn(N5)2and water, which are beneficial to improvement of the stability of Zn(N5)2. This may indicate the solvents that have strong interactions with the cyclo‐N5−candidate may improve the possibility of success of synthesis. The effect of nine solvents on Zn(N5)2was studied using the density functional theory and the polarized continuum model. The results indicated the stability of Zn(N5)2increases with increasing dielectric constants. To understand the stabilization mechanism of Zn(N5)2by water, further studies were performed using the explicit solvent model.

An efficient synthesis of cyanoalkylated heteroarenes via iron-catalyzed direct C–H cyanoalkylation of heteroarenes has been developed. Structurally diverse cyanoalkyl motifs generated through C–C bond cleavage of cyclobutanone oxime esters have been introduced into quinoxalin-2(1H)-ones, flavone, benzothiazoles, and caffeine in good to excellent yields. Remarkably, less-strained cyclopentanone and unstrained cyclohexanone oxime esters were also amenable substrates in this cyanoalkylation reaction.

Mine tailings are extremely oligotrophic environments frequently contaminated with elevated As and Sb, making As(III) and Sb(III) oxidation potentially important energy sources for the tailing microbiome. Although they have been proposed to share similar metabolic pathways, a systemic comparison of the As(III) and Sb(III) oxidation mechanisms and energy utilization efficiencies requires further elucidation. In this study, we employed a combination of physicochemical, molecular, and bioinformatic analyses to compare the kinetic and genetic mechanisms of As(III) and Sb(III) oxidation as well as their respective energy efficiencies for fueling the key nutrient acquisition metabolisms. Thiobacillusand Rhizobiumspp. were identified as functional populations for both As(III) and Sb(III) oxidation in mine tailings by DNA-stable isotope probing. However, these microorganisms mediated As(III) and Sb(III) oxidation via different metabolic pathways, resulting in preferential oxidation of Sb(III) over As(III). Notably, both As(III) and Sb(III) oxidation can facilitate nitrogen fixation and phosphate solubilization in mine tailings, with Sb(III) oxidation being more efficient in powering these processes. Thus, this study provided novel insights into the microbial As(III) and Sb(III) oxidation mechanisms and their respective nutrient acquisition efficiencies, which may be critical for the reclamation of mine tailings.

A sustainable, cyanide-free synthesis of alkyl nitriles via the aerobic oxidative deconstruction of unstrained cycloalkanones with ammonium salts has been developed. Using inexpensive and stable ammonium salts as the nitrogen source, a variety of alkyl nitriles containing a distal carbonyl group were obtained in good yields under visible-light-promoted iron catalysis. This protocol is characterized by mild conditions, abundant and environmentally benign materials, and high atom and step economy with minimal waste generation. The primary mechanism study revealed that 1O2is likely to be involved in this reaction.

An iron-catalyzed decarboxylative olefination of unstrained carbon–carbon bonds via alkoxyl radical induced C–C bond cleavage is presented. This protocol features mild conditions (room temperature, redox-neutral), good substrate scope and functional group compatibility, as well as excellent stereoselectivity, thus providing a facile access to the distal alkenyl ketones.

Environmentally persistent free radicals (EPFRs) are emerging contaminants occurring in combustion-borne particulates and atmospheric particulate matter, but information on their formation and behavior on fly ash from municipal solid waste (MSW) incinerators is scarce. Here, we have found that MSW-associated fly ash samples contain an EPFR concentration of 3–10 × 1015spins g–1, a line width (ΔHp-p) of ∼8.6 G, and a g-factor of 2.0032–2.0038. These EPFRs are proposed to be mixtures of carbon-centered and oxygen-centered free radicals. Fractionation of the fly ash-associated EPFRs into solvent-extracted and nonextractable radicals suggests that the solvent-extracted part accounts for ∼45–73% of the total amount of EPFRs. Spin densities of solvent-extracted EPFRs correlate positively with the concentrations of Fe, Cu, Mn, Ti, and Zn, whereas similar correlations are comparatively insignificant for nonextractable EPFRs. Under natural conditions, these two types of EPFRs exhibit different stabilization that solvent-extracted EPFRs are relatively unstable, whereas the nonextractable fraction possesses a long life span. Significant correlations between concentrations of solvent-extracted EPFRs and generation of hydroxyl and superoxide radicals are found. Overall, our results suggest that the fractionated solvent-extracted and nonextractable EPFRs may experience different formation and stabilization processes and health effects.

The efficient copper-catalyzed cyanoalkylation of amines via C–C bond cleavage has been demonstrated. Distinctive features of this procedure involves mild conditions, broad range of nitrogen nucleophiles, high selectivity, and good functional group tolerance, thus providing a useful approach for the C(sp3)–N bond formations. Most importantly, this protocol is applicable to the late-stage functionalization of natural products, amino acid esters, and drugs. Mechanistic studies suggest that a radical intermediate was involved in this transformation.

An efficient iron-catalyzed intermolecular remote C(sp3)–H heteroarylation of alkyl ketones has been developed via an iminyl radical-triggered 1,5-hydrogen-atom transfer (HAT) cascade. This protocol was amenable to a wide variety of alkyl ketones and heteroaryls, thus providing a straightforward method for the late-stage functionalization of alkylketones and heteroaryls.

A three-component coupling of aryl bromides, arylboron reagents, and alkenylarenes is presented. The method tolerates a variety of substitution patterns on all of the components. In particular, 1,2-disubstituted alkenylarenes are suitable and undergo highly diastereoselective diarylation.

An iron-catalyzed redox-neutral, decarboxylative olefination of cycloketone oxime esters with α,β-unsaturated carboxylic acids has been developed. This reaction involves an iminyl radical mediated C–C bond cleavage/radical addition/decarboxylation cascade. This protocol is highlighted by its low-cost catalytic system and readily accessible starting materials, as well as broad substrate scope, thus providing facile access to structurally diverse cyano-containing alkenes.

Extracellular polymeric substances (EPS) were extracted from biofilms in a continuously running biological aerated filter (BAF) reactor by five different methods, including heating treatment at 60°C, cation exchange resin (CER), EDTA, sodium hydroxide (NaOH), and sulfuric acid (H2SO4). Highspeed centrifugation was used as a control method. The results showed that the extraction method played a great role on EPS yields and chemical compositions, whereas no remarkable difference in their structural characteristics was observed. Heating treatment was determined as the most effective protocol with the highest EPS recovery and lowest cell damage. The total amount of the extracted EPS was 131.6 mg/g volatile suspended solids (VSS), while the DNA content only accounted for 7.0%. The intensity of absorption bands in the UV-visible (UV-vis) spectra was in agreement with chemical compositions of the extracted EPS. In addition, the Fourier transform infrared (FT-IR) results indicated that no noticeable effect was found on EPS structures extracted by different methods. However, both UV-vis and FT-IR spectroscopic analyses revealed that chemical reagents used during extraction processes might contaminate the extracted EPS, and then interfered with the determination of proteins in EPS.

A concise Fe-catalyzed alkylazidation of α-trifluoromethylalkenes via a C–C bond cleavage/radical addition/azidation cascade is described. This protocol features a broad substrate scope, excellent functional group compatibility, and the ability to be performed on a gram scale, thus offering a practical and step-economic approach to the synthetically useful tertiary α-trifluoromethyl azides.

An array of redox-neutral alkylation/cyclization cascade reactions of N-functionalized acrylamides with cycloalkyl hydroperoxides were achieved via the alkoxyl radical-triggered C–C bond cleavage. Through adjusting the radical acceptors on the Natom, a variety of keto-alkylated chain-containing azaheterocycles, including indolo[2,1-a]isoquinolin-6(5H)-ones, quinoline-2,4-diones, and pyrido[4,3,2-gh]phenanthridines were constructed by a one-pot procedure with good yields and excellent functional group tolerance.

Objective Intracorporeal esophagojejunostomy remains a challenging technique in totally laparoscopic total gastrectomy (TLTG) because of the lack of an established standard anastomosis method. However, π-shaped esophagojejunostomy in TLTG is reportedly safe and feasible. Therefore, we evaluated the short-term surgical outcomes of our modified π-shaped esophagojejunostomy in TLTG.Methods This study involved patients without neoadjuvant therapy diagnosed with gastric cancer who underwent TLTG by the same surgeon with modified π-shaped esophagojejunostomy from April 2018 to October 2019. Clinicopathologic data were collected and retrospectively analyzed.Results Forty patients diagnosed with gastric cancer were included. The mean operative time and estimated blood loss were 264.6 ± 56.9 minutes and 68.5 ± 53.3 mL, respectively. Postoperative flatus occurred at 4.6 ± 1.7 days. The mean time to resumption of diet was 7.4 ± 1.7 days postoperatively. One patient was diagnosed with anastomotic leakage and managed with conservative therapy. Pleural effusion was the most common complication, occurring in four (10%) patients. One patient developed intra-abdominal bleeding that required reoperation. Other complications were atrial fibrillation and wound infection. No mortality occurred during the 6-month follow-up.Conclusions Modified π-shaped esophagojejunostomy is safe and feasible for intracorporeal anastomosis in TLTG and showed favorable surgical outcomes in this study.

An efficient iron‐catalyzed allylation of cycloalkyl hydroperoxides with allylic sulfones via C−C bond cleavage is presented. This protocol provides an efficient approach to a wide range of distally allylated ketones with good functional group tolerance and high regioselectivity under redox‐neutral conditions. Preliminary mechanistic study implies a radical process might be involved in this reaction. An efficient iron‐catalyzedallylation of cycloalkyl hydroperoxides with allylic sulfones via the alkoxy radical‐mediated C−C bond cleavage under redox‐neutral conditions is presented. Structurally diverse cycloalkyl hydroperoxides such as five‐, six‐, seven‐, eight‐ and even twelve‐membered ring proceeded β‐scission successfully to furnish a series of distally allylated ketones.

An efficient copper catalysis system for the chloroamination of alkynes with chlorosulfonamide at room temperature is described, providing a highly regio‐ and stereoselective procedure for the synthesis of (E)‐β‐chloro‐enesulfonamides in moderate to good yields.

The hydrophobic association properties of a modified polyacrylamide (HMPAM) solution are attributed to the composition of the solution and environmental factors. In this study, the hydrophobic association of fluorocarbon-modified polyacrylamide aqueous solutions has been investigated on a mesoscopic level by considering the variation of root mean square (RMS) end-to-end distances using dissipative particle dynamics (DPD) simulations. The hydrophobic association depends on the hydrophobic behavior of the groups incorporated, the environmental temperature, the addition of salts and the shear. The embedded fluorocarbon units in the polyacrylamide chains are trifluoroethyl methacrylate, hexafluorobuyl methacrylate and dodecafluoroheptyl methacrylate, respectively, and the corresponding copolymers are expressed as P(AM-AANa-3F), P(AM-AANa-6F) and P(AM-AANa-12F). The modeling results show that P(AM-AANa-12F) has the strongest hydrophobic interactions among the three copolymers. The hydrophobic association of P(AM-AANa-12F) solutions in pure water is lower than that of corresponding salt-water solutions and shows stronger positive salinity sensitivity. P(AM-AANa-12F) can maintain its hydrophobic association in aqueous solution at high temperature, and its three-dimensional network can be reformed after shear. These conclusions are consistent with the experimental and theoretical results.

Bioassay-guided fractionation of an EtOAc extract of the leaves of Rosa laevigataafforded two new 19-oxo-18,19-seco-ursane-type triterpenes (1and 3), a new ursane-type nortriterpene (2), a new ursane-type triterpene lactone saponin (4), and two new oleanane-type triterpenoids (5and 6), together with eight known triterpenoids (7−14). Compound 1, a 19-oxo-18,19-seco-28-norursane, possesses a conjugated diene between C-12 and C-17. Several of the isolated compounds (1, 5, 7, 11, and 13) exhibited moderate activities in anti-inflammatory assays in vitro.

To the analysis and further development of straight-racket-hit skill of table tennis, visual simulation is established to help finding its character through comparing with straight racket backhand skill. To overcome such flaws as unable to exert enough force and difficult to determine a strike point, an optimal angle to achieve the skill is got through analyzing force of different angle of wrist and forearm. Through analyzing the visual simulation of mechanical arm, a systematic theory is established to orient the training of straight-racket-hit skill.

Resol crosslinked polyacrylamide (PAM) hydrogel can be used as the chemical flooding agent in enhanced oil recovery because of its excellent temperature- and salt-resistant properties. It is known that crosslinking reactions, including ortho–ortho, ortho–para and para–para polycondensation of resols and ortho and para polycondensation between PAM and resol, are involved in the researched system, but the extent and activity of the reactions are still not clear. In this study, these crosslinking reactions were all investigated by a combination of molecular simulation and X-ray photoelectron spectroscopy (XPS) techniques. When propionamide was investigated as the model compound of PAM, the Gibbs-free energy and energy barrier of the reactions were calculated by density-functional theory. The atomistic model of the crosslinked PAM network was constructed by molecular mechanics and molecular dynamics, and the density of crosslinked PAM and the amount of active crosslinking sites were obtained. The results show that these reactions occurred spontaneously at 353?K because of thermodynamics. The ortho condensation between PAM and resol is the main kinetic reaction, and the reacted amidocyanogen reached 60% of the total amount, which is consistent with the XPS analysis.

Switchable in situSO2capture and CF3migration of enol triflates with peroxyl compounds under iron catalysis are presented. By regulating the structure of peroxides, a variety of keto-functionalized dialkyl sulfones and α-trifluoromethyl ketones were selectively synthesized in good yields under mild conditions.

Remediation of arsenic (As)-contaminated wastewater by treatment wetlands (TWs) remains a technological challenge due to the low As adsorption capacity of wetland substrates and the release of adsorbed As to pore water. This study investigated the feasibility of using immobile iron-rich particles (IIRP) to promote As retention and to regulate As biotransformation in TWs. Iron-rich particles prepared were immobilized in the interspace of a gravel substrate. TWs with IIRP amendment (IIRP-TWs) achieved a stable As removal efficiency of 63 ± 4% over 300 days, while no As removal or release was observed in TWs without IIRP after 180 days of continuous operation. IIRP amendment provided additional adsorption sites and increased the stability of adsorbed As due to the strong binding affinity between As and Fe oxides. Microbially mediated As(III) oxidation was intensified by iron-rich particles in the anaerobic bottom layer of IIRP-TWs. Myxococcusand Fimbriimonadaceaewere identified as As(III) oxidizers. Further, metagenomic binning suggested that these two bacterial taxa may have the capability for anaerobic As(III) oxidation. Overall, this study demonstrated that abiotic and biotic effects of IIRP contribute to As retention in TWs and provided insights into the role of IIRP for the remediation of As contamination.

The paper examines a seller’s offering of free add-ons in services. We build a stylized model where the seller decides the level of add-on provision to enhance its core service, and consumers make discrete choices between the seller and an outside option. When the seller supplies its service through a single channel, we show that the optimal add-on provision is unimodal in the difference between the seller’s service quality and the outside option, comparable with the existing literature. When the service is supplied through multiple channels, we show that the seller may make nonidentical add-on provisions among channels. If the cost of add-on provision is low, the seller should adopt a differentiation strategy. If the cost is high, the seller should adopt a homogenization strategy. Various extensions are considered to establish the robustness of our results.

We compared two reflection-mode negative electron affinity (NEA) GaAs photocathode samples that are grown by molecular beam epitaxy with p-type beryllium doping. One sample is uniform doping, and another is gradient doping. Experimental curves of spectral response sensitivity and quantum efficiency are obtained. The thicknesses of the two cathodes are both 2.6 μm. The integrated sensitivity of the uniform doping one is 1966 μA/lm, and that of the gradient-doping one is 2421 μA/lm. The escape probability and diffusion length are fitted from the spectral response curves. For the uniform-doping sample, the escape probability is 0.45 and the diffusion length is 5 μm. For the gradient-doping sample, the escape probability is 0.55 and the diffusion length is 5.5 μm.

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The filling process of plastic precise gear is simulated by CAE software and the factors that influence injection molding accuracy in single cavity mold are discussed in this paper. With the assistant of visualization technology, the mechanism of filling unbalance which influences efficient injection molding was especially studied. The model of filling unbalance was supposed that was verified experimentally by visualization technique. It is clarified that the mechanism of filling unbalance results from dissymmetrical temperature distribution on the cross-section of runner, which is strongly influenced by the shear heat and the cooling process in the runner. At the same time, a new method was proposed for improving the filling imbalance by applying appropriate injection molding process without any changes in runner shape of multi-cavity mold.

The geometries of four isomers of the trimethylsilyl substituted phthalocyanine (Pc)—I, II, III, and IV—have been optimized at the B3LYP/3-21G level of density functional theory. Normal-mode vibrational analyses have been performed and their standard thermodynamic functions, molar fractions, and electronic absorption spectra calculated. Single-point energies have been calculated at the B3LYP/6-311G* level for all isomers to evaluate the heats of formation from an isodesmic reaction. It is found that substitution has little influence on the geometry and electronic structures of the Pc framework. The corresponding geometric parameters in various isomers are close. According to the B3LYP/6-311G*//B3LYP/3-21G results, substitution at the peripheral position of the isoindole with an inner hydrogen is most favorable. The energies increase in the order of IV < II < III < I, and the energy difference between IV and I is 5.75 kJ/mol. The molar fractions of IV, II, III, and I are 0.80, 0.17, 0.02, and 0.02 and the heats of formation are 2009.96, 2010.10, 2015.85, and 2016.52 kJ/mol, respectively. This indicates that nonperipheral substituted Pcs have higher energy and little production because they are not stable under the considered conditions. The electronic spectra of the substituted Pcs calculated using the ZINDO method have two strong Q absorption bands around 700 nm and one B band around 300 nm that are slightly shifted compared with those in Pc. The ratios of the oscillator strength of the B band to the Q bands are much lowered by trimethylsilyl substitution. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002

Objective To explore the risk factors associated with esophagojejunal anastomotic leakage (EJAL) after curative total gastrectomy combined with D2 lymph node dissection for gastric cancer.Methods We reviewed the data for 390 consecutive patients undergoing Roux-en-Y esophagojejunostomy reconstruction after total gastrectomy. Multivariate analysis was performed using a logistic regression model to identify the independent risk factors for EJAL.Results Of the 390 patients enrolled in this study, EJAL occurred in 10 patients (2.6%), and one patient (1/10) with EJAL died. Univariate analysis identified age, alcohol consumption, pulmonary insufficiency, and intraoperative blood loss as risk factors for EJAL. Of these four risk factors, age and alcohol consumption were retained as independent risk factors by multivariate analysis.Conclusion Surgeons should be very careful regarding anastomotic leakage after esophagojejunal anastomosis, perioperatively, especially in patients with advanced age and a history of alcohol consumption. Pulmonary insufficiency and intraoperative blood loss, although not identified as independent risk factors, should also be considered.

With the development of tea production, treating tea waste has become a problem that cannot be ignored. Here, we reprocessed tea waste to create a new kind of biomass material and named it "CHAMU". We found that tea waste is a good fiber raw material and can improve the degradation rate of PLA composites in the soil. Based on the above findings, we established a tea waste recycling system. During the processing, it was found that tea stems, tea residue had better plasticity than wood-shaving materials. According to this characteristic, we designed a series of "CHAMU products" to explore "CHAMU" materials in product design.

This paper proposes and explains the concept of "Chinese Pinyin of tea and wood (CHAMU)" and the establishment of the "Tea Waste Recycling System" for mitigating the problem of tea waste disposal in the tea production process. Based on the "reuse of fully biodegradable waste" proposed in the "Tea Waste Recycling System," this paper investigates existing biodegradation studies related to plant materials and analyzes the factors that contribute to the degradation of plant material. This paper analyzes the composition of tea waste and establishes a theoretical basis for the biodegradation of tea waste. The soil-buried method was used to test the degradation performance of samples prepared from polylactic acid (PLA) and tea waste composites made by injection molding.This paper mainly focuses on the experiment and discussion of the biodegradability of "CHAMU" materials and considers a theoretical basis to assist in the establishment of a tea waste recycling system.

This Charpy impact toughness and microstructure evolution of simulated heat affected zone (HAZ) for E40 ship plate steel have been investigated in this experiment. Simulation of large heat input welding was conducted by thermal simulator to research microstructure evolution of HAZ at 1400degC peak temperature. Results show that microstructure at HAZ was mainly composed of high intensity of acicular ferrite (AF) and intragranular ferrite (IGF), and grain boundaries ferrite (GBF). Hardness of HAZ decreases with heat input (HI) increasing. Impact toughness for steel specimens with HI of 500 kJ/cm was 141 J. TiN precipitates nucleation and growth at HAZ was analyzed by TEM, indicating that TiN size increases and the number of TiN decreases at HAZ with HI increasing. The reason is that the specimens with HI of 400 kJ/cm has longer cooling time from 800degC to 500degC than 120 kJ/cm, which is favorable to growth of TiN particle at HAZ.

Raman spectroscopy has been widely used as an important clinical tool for real-time in vivo cancer diagnosis. Raman information can be obtained from whole organisms and tissues, at the cellular level and at the biomolecular level. The aim of this paper is to review the newest developments of Raman spectroscopy in the field of breast cancer diagnosis and treatment. Raman spectroscopy can distinguish malignant tissues from noncancerous/normal tissues and can assess tumor margins or sentinel lymph nodes during an operation. At the cellular level, Raman spectra can be used to monitor the intracellular processes occurring in blood circulation. At the biomolecular level, surface-enhanced Raman spectroscopy techniques may help detect the biomarker on the tumor surface as well as evaluate the efficacy of anticancer drugs. Furthermore, Raman images reveal an inhomogeneous distribution of different compounds, especially proteins, lipids, microcalcifications, and their metabolic products, in cancerous breast tissues. Information about these compounds may further our understanding of the mechanisms of breast cancer.

The carmine spider mite, Tetranychus cinnabarinus (Boisduval), is a major agriculture pest. It can be found worldwide, has an extensive host plant range, and has shown resistance to pesticides. Organophosphate and carbamate insecticides account for more than one-third of all insecticide sales. Insecticide resistance and the toxicity of organophosphate and carbamate insecticides to mammals have become a growing concern. Acetylcholinesterase (AChE) is the major targeted enzyme of organophosphate and carbamate insecticides. In this study, we fully cloned, sequenced and characterized the ace1 gene of T. cinnabarinus, and identified the differences between T. cinnabarinus AChE1, Tetranychus urticae Koch AChE1, and human AChE1. Resistance-associated target-site mutations were displayed by comparing the AChE amino acid sequences and their AChE three-dimensional (3D) structures of the insecticide-susceptible strains of T. cinnabarinus and T. urticae to that of a T. urticae-resistant strain. We identified variation in the active-site gorge and the sites interacting with gorge residues by comparing AChE1 3D structures of T. cinnabarinus, T. urticae, and humans, though their 3D structures were similar. Furthermore, the expression profile of T. cinnabarinus AChE, at the different developmental stages, was determined by quantitative real-time polymerase chain reaction; the transcript levels of AChE were higher in the larvae stage than in other stages. The changes in AChE expression between different developmental stages may be related to their growth habits and metabolism characteristics. This study may offer new insights into the problems of insecticide resistance and insecticide toxicity of nontarget species.

Substitutions at the benzene ring of the indole substrates are well tolarated, whereas with a 3‐substituted indole no corresponding product is obtained.

The structures of two new sesquiterpene lactones, 11,13β-dihydroixerin Z (1) and Ixerin Z2 (2) isolated from Ixeris sonchifoliawere determined to be 3-hydroxy-1(10),3-guaiadiene-12,6-olide-2-one-3-O-β-D-glucopyranoside and 1(10),3,11 (13)-guaiatriene-12,6-olide-2-one-3-O-[6′-(4″-hydroxybenzyl lactyl)]-β-D-glucopyranoside, respectively on the basis of detailed spectral analysis.