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Colorectal cancer is the third leading cause of cancer-related deaths in the United States and the third most common cancer in men and women. Around 20% colon cancer cases are closely linked with colitis. Both environmental and genetic factors are thought to contribute to colon inflammation and tumor development. However, the genetic factors regulating colitis and colon tumorigenesis remain elusive. Since reactive oxygen species (ROS) is vitally involved in tissue inflammation and tumorigenesis, here we employed a genome-wide CRISPR knockout screening approach to systemically identify the genetic factors involved in the regulation of oxidative stress. Next generation sequencing (NGS) showed that over 600 gRNAs including the ones targeting LGALS2 were highly enriched in cells survived after sublethal H2O2 challenge. LGALS2 encodes the glycan-binding protein Galectin 2 (Gal2), which is predominantly expressed in the gastrointestinal tract and downregulated in human colon tumors. To examine the role of Gal2 in colitis, we employed the dextran sodium sulfate (DSS)-induced acute colitis model in mice with (WT) or without Lgals2 (Gal2-KO) and showed that Gal2 deficiency ameliorated DSS-induced colitis. We further demonstrated that Gal2-KO mice developed significantly larger tumors than WT mice using Azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced colorectal cancer model. We found that STAT3 phosphorylation was significantly increased in Gal2-deficient tumors as compared to those in WT mice. Gal2 overexpression decreased the proliferation of human colon tumor epithelial cells and blunted H2O2-induced STAT3 phosphorylation. Overall, our results demonstrate that Gal2 plays a suppressive role in colon tumor growth and highlights the therapeutic potential of Gal2 in colon cancer.

A collector with high perveance, efficient recuperation, and low secondary emissions is required for the 450-keV electron cooler in the HIAF accelerator complex. To optimize the collection efficiency of the collector, a simulation program, based on the Monte Carlo simulations, was developed in the world’s first attempt to calculate the electron collection efficiency. In this program, the backscattering electrons and secondary electrons generated on the collector surface are calculated using a Monte Carlo approach, and all electron trajectories in the collector region are tracked by the Runge–Kutta method. In this paper, the features and structure of our program are described. The backscattering electron yields, with various collector surface materials, are calculated using our program. Moreover, the collector efficiencies for various collector structures and electromagnetic fields are simulated and optimized. The measurement results of the collection efficiency of the HIAF collector prototype and the CSRm synchrotron are also reported. These experimental results were in good agreement with the simulation results of our program.

Integrated circuits (ICs) and optoelectronic chips are the foundation stones of the modern information society. The IC industry has been driven by the so-called “Moore’s law” in the past 60 years, and now has entered the post Moore’s law era. In this paper, we review the recent progress of ICs and optoelectronic chips. The research status, technical challenges and development trend of devices, chips and integrated technologies of typical IC and optoelectronic chips are focused on. The main contents include the development law of IC and optoelectronic chip technology, the IC design and processing technology, emerging memory and chip architecture, brain-like chip structure and its mechanism, heterogeneous integration, quantum chip technology, silicon photonics chip technology, integrated microwave photonic chip, and optoelectronic hybrid integrated chip.

Interest Flooding Attack (IFA) is one of the main security threats for the Named Data Networking (NDN). Most of its existing countermeasures enable intermediate routers near the attackers to independently detect the attack and consider the typical attack scenario in which attackers directly send malicious Interests at a constant and relatively high rate after the attack starts. Moreover, they may also throttle legitimate Interests when enforcing the existing defense measures at intermediate routers as it is still difficult for them to distinguish the Interests issued by attackers from those issued by legitimate consumers. Instead, this work aims at a more sophisticated attack scenario in which attackers start the attack at a relatively lower rate but gradually speed up to keep the Pending Interest Tables (PITs) of the victims increasing to finally deplete the PIT resources for legitimate consumers. It is relatively difficult for intermediate routers to independently and timely detect such a sophisticated IFA. To solve this problem, we propose a mechanism to detect and mitigate the sophisticated IFA from the network-wide view, dubbed as DMNWV. In DMNWV, a central controller monitors the network and makes a comprehensive and prompt decision on whether there is an ongoing IFA based on the overall state of the whole network collected from the abnormity information reports sent by the first-hop routers of attackers. Attack sources can be directly located after an IFA is determined, and then the routers directly connected to attackers (i.e., access routers) can take targeted measures based on the located attackers to prevent malicious Interest from entering the network without throttling legitimate Interests. We conduct an experimental study to evaluate the performance of DMNWV, explore the parameter settings of the attack detection algorithm at access routers, and measure the communication overhead of the central controller. The experimental results validate that DMNWV can timely detect and mitigate the sophisticated IFA without throttling requests from legitimate consumers with significantly low communication overhead of the central controller, which will not bring about too much burden to the network.

The anaerobic oxidation of ammonium (anammox) process plays a critical role in the loss of nitrogen (N) in paddy soils, yet the response of anammox to different fertilization is not well documented. In this study, three different fertilized (control, CK; soil treated with inorganic fertilizers, NPK; soil treated with inorganic fertilizer and involving the incorporation of straw, NPKS) paddy soils were selected to investigate the activity, functional gene abundance, diversity, and composition of anammox bacterial community using isotope-tracing technique, quantitative PCR assays, and Illumina sequencing. The anammox rate in the NPKS treatment was 2.4 nmol N g−1 soil h−1, significantly higher than that in CK and NPK treatments (1.7 and 1.8 nmol N g−1 soil h−1, respectively). Potential anammox contributed 6.2–7.8% to total N loss with the remainder being due to denitrification. Significant differences in the number of hydrazine synthase β-subunit (hzsB) gene were observed in three treatments with the highest value being observed in the NPK treatment. The anammox rate of per functional gene in the NPKS treatment (11.4 fmol day−1) was higher than that in CK and NPK treatments (8.3 and 7.0 fmol day−1, respectively). Three genera of anammox bacteria were identified: Candidatus Brocadia, Candidatus Anammoxoglobus, and Candidatus Scalindua, with Candidatus Brocadia being the dominant. Anammox bacteria diversity was significantly lower in the NPK than in CK and NPKS treatments as shown by Shannon, Simpson, Chao 1, and ACE indices (p

We reported an unprecedented chemiluminescence (CL) behavior of polyamine-functionalized carbon dots induced by Fe3+–H2O2 Fenton-like system. The first-step CL intensity increased with the increasing of the concentration of H2O2 and Fe3+, when the Fe3+ concentration came to 10−3 M, the unprecedented two-step CL behavior appeared. The CL intensity of BPEI-CDs induced by Fenton-like system was about 10 times stronger than that of naked CDs. The possible two-step CL mechanism was speculated based on the photoluminescence spectra, CL emission spectra, and the effects of radical scavengers on the CL intensity. Radiative recombination of the injected holes by strong oxidant perferrate formed through Fe3+–H2O2 reaction and the ·OH generated from successive Fenton reaction with the thermally excited electrons was proposed, which further facilitate full understanding about the optical properties of carbon dots.

Reaumuria trigyna is a highly xeric small shrub and is a rare wild plant in Mediterranean areas. The flavonoid biosynthesis pathway in R. trigyna is strongly activated under salt stress, and many genes related to this pathway showed significant differences in transcript abundance under salt stress in a previous transcriptomic profiling analysis. The F3H gene, which encodes flavanone-3-hydroxylase, is an essential gene in the flavonoid biosynthetic pathway. The transcript levels of two F3H genes, RtF3H1 and RtF3H2, were increased in R. trigyna not only under salt stress but also under drought and cold stresses, and by abscisic acid. We measured the transcript levels of the two genes in different organs. There were high transcript levels of RtF3H1 in stems, and high transcript levels of RtF3H2 in roots and stems. The full-length cDNAs for RtF3H1 (Accession No. AB850638) and RtF3H2 (Accession No. AB850639) were cloned and were found to encode 353- and 358-amino-acid proteins, respectively. Escherichia coli overexpressing RtF3H1 or RtF3H2 showed better growth than that of a control E. coli line under various stress treatments. The survival rate of the recombinant E. coli strain expressing RtF3H2 was higher than that of the strain expressing RtF3H1 under salt and drought stresses.

Rapid improvement in the efficiency of GaN-based LEDs not only speed up its applications for general illumination, but offer the possibilities for data transmission. This review is to provide an overview of current progresses of GaN-based LEDs for light communications. The modulation bandwidth of GaN-based LEDs has been first improved by optimizing the LED epilayer structures and the modulation bandwidth of 73 MHz was achieved at the driving current density of 40 A/cm2 by changing the multi-quantum well structures. After that, in order to increase the current density tolerance, different parallel flip-chip micro-LED arrays were fabricated. With a high injected current density of ~7900 A/cm2, a maximum modulation bandwidth of ~227 MHz was obtained with optical power greater than 30 mW. Besides the increase of carrier concentrations, the radiative recombination coefficient B was also enhanced by modifying the photon surrounding environment based on some novel nanostructures such as resonant cavity, surface plasmon, and photonic crystals. The optical 3 dB modulation bandwidth of GaN-based nanostructure LEDs with Ag nanoparticles was enhanced by 2 times compared with GaN-based nanostructure LEDs without Ag nanoparticles. Our results demonstrate that using the QW-SP coupling can effectively help to enhance the carrier spontaneous emission rate and also increase the modulation bandwidth for LEDs, especially for LEDs with high intrinsic IQE. In addition, we discuss the progress of the faster color conversion stimulated by GaN-based LEDs.

Fanconi anemia (FA) is a rare cancer-predisposing genetic disease mostly caused by improper regulation of the monoubiquitination of Fanconi anemia complementation group D2 (FANCD2). Genetic studies have indicated that ubiquitin conjugating enzyme UBE2T and HHR6 could regulate FANCD2 monoubiquitination through distinct mechanisms. However, the exact regulation mechanisms of FANCD2 monoubiquitination in response to different DNA damages remain unclear. Here we report that UBE2W, a new ubiquitin conjugating enzyme, could regulate FANCD2 monoubiquitination by mechanisms different from UBE2T or HHR6. Indeed, UBE2W exhibits ubiquitin conjugating enzyme activity and catalyzes the monoubiquitination of PHD domain of Fanconi anemia complementation group L (FANCL) in vitro. UBE2W binds to FANCL, and the PHD domain is both necessary and sufficient for this interaction in mammalian cells. In addition, over-expression of UBE2W in cells promotes the monoubiquitination of FANCD2 and down-regulated UBE2W markedly reduces the UV irradiation-induced but not MMC-induced FANCD2 monoubiquitination. These results indicate that UBE2W regulates FANCD2 monoubiquitination by mechanisms different from UBE2T and HRR6. It may provide an additional regulatory step in the activation of the FA pathway.

A micro-plate magnetic chemiluminescence immunoassay was developed for rapid and high throughput detection of carcinoembryonic antigens (CEA) in human sera. This method was based on a sandwich immunoreaction of fluorescein isothiocyanate (FITC)-labeled anti-CEA antibodies, CEA antigens, and horseradish peroxidase (HRP)-conjugated anti-CEA antibodies in micro-plate. The immunomagnetic particles coated with anti-FITC antibodies were used as the solid phase for the immunoassay. The separation procedure was carried out by a magnetic plate adaptor and the luminol-hydrogen peroxide (H2O2)-HRP system was employed for the chemiluminescence detection. The proposed method combined the advantages of the micro-plate reactor and magnetic particle separation technology with the linear range of 5–250 ng·mL−1. The detection limit of CEA was 0.61 ng·mL−1. The coefficient of the variation was less than 7% and 13% for intra-assay and inter-assay precision, respectively. Compared with the commercial micro-plate chemiluminescent kit, the proposed method showed a good correlation.

Ten highly potent estrogens including estrone (E(1)), 17 beta-estradiol (E(2)), estriol (E(3)), 4-hydroxyestrone (4-OHE(1)), 2-hydroxyestradiol (2-OHE(2)), 16 alpha-hydroxyestrone (16 alpha-OHE(1)), 2-methoxyestrone (2-MeO-E(1)), 2-methoxyestradiol (2-MeO-E(2)), diethylstilbestrol (DES), 17 alpha-ethynylestradiol (EE(2)) were identified and quantified by solid-phase extraction followed by liquid chromatography-mass spectrometry. An improved two-step SPE process was employed in this work. C18 cartridge was used for both enrichment of all target estrogens and retention of some nonpolar impurities, and then a polar florisil cartridge was subsequently used to separate the interested estrogens from the polar impurities. After this pretreatment for water samples, the results showed clean chromatograms without interference from matrix effects. Besides, this method was accurate (recovery percentages between 70.4 and 106.8% for river water and 73.4 and 101.3% for raw sewage, except 4-OHE(1) and 2-OHE(2)), and precise (RSD varying between 1.3 and 17.8% for river water and 3.4 and 16.7% for raw sewage). In the optimized condition, this method was used to verify the presence of the target analytes in the Qinghe River and influent of sewage treatment plant in the northwest of Beijing, China. Some estrogens were detected in the river water and sewage water samples at a relatively high concentration. The developed method proved to be effective for analyzing estrogen compounds in complex matrices. Moreover, the achieved results demonstrated that a great concern should be addressed to the potential risk of the presence of estrogens in the aquatic environment.

2,4,6-Trichlorophenol (2,4,6-TCP)-imprinted micro- and submicrospheres prepared by precipitation polymerization were compared with templated materials obtained by conventional bulk polymerization. The influence of the type and amount of functional monomer, the type and amount of cross-linker, polymerization temperature, porogen, and the ratio of template molecule and functional monomer to cross-linker on the size of the obtained particles were investigated. UV-Vis spectrophotometer experiments revealed that the microsphere polymers provided higher affinity to the template in contrast to imprinted polymers prepared by bulk polymerization. The binding properties of the microspheres, including binding isotherms and affinity distribution, were studied via Freundlich isotherm affinity distribution (FIAD) analysis. The obtained results indicated that microspheres prepared by precipitation polymerization provided superior rebinding properties during equilibrium binding in contrast to bulk polymers and submicrosphere polymers. Moreover, release experiments showed that 80% of rebound 2,4,6-TCP was released from the imprinted microspheres within the first 2 h, while more intimately bound 2,4,6-TCP molecules were released in the following 40 h. The morphologies and porosities of the resulting imprinted materials were characterized by scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis, respectively. The microsphere polymers exhibited a regular spherical shape with a high degree of monodispersity to the corresponding bulk polymers. Furthermore, the micro- and submicrospheres were characterized by narrow distribution of pores in contrast to a heterogeneity index of m = 0.6647 for the microsphere imprinted polymer.

Novel Ti-containing wormlike mesoporous silica (Ti-WMS) had been synthesized through assembly of preformed titanosilicate-1 precursors with long-chain alkylamines at room temperature. The structural and catalytic properties of prepared material were characterized by a variety of techniques including powder X-ray diffraction, transmission electron microscopy, infrared spectroscopy, UV–Visible spectroscopy, N2 physical adsorption and oxidative desulfurization reactions. The hydrothermal stability of Ti-WMS in steam and boiling water was investigated with comparing to the conventional Ti-HMS. It has been shown that Ti-WMS, relative to Ti-HMS, possesses disordered mesostructure, thicker porous walls, improved amount of micropores and higher catalytic activities, which can be attributed to the existence of zeolitic building units in it. However, there is no enhancement in hydrothermal stability of Ti-WMS assembled from zeolite precursors relative to Ti-HMS prepared through conventional process.

Highly sensitive flow-injection chemiluminescence (CL) combined with molecularly imprinted solid-phase extraction (MISPE) has been used for determination of 2,4-dichlorophenol (2,4-DCP) in water samples. The molecularly imprinted polymer (MIP) for 2,4-DCP was prepared by non-covalent molecular imprinting methods, using 4-vinylpyridine (4-VP) and ethylene glycol dimethacrylate (EGDMA) as the monomer and cross-linker, respectively. 2,4-DCP could be selectively adsorbed by the MIP and the adsorbed 2,4-DCP was determined by its enhancing effect on the weak chemiluminescence reaction between potassium permanganate and luminol. The enhanced CL intensity was linear in the range from 1 x 10(-7) to 2 x 10(-5) g mL(-1). The LOD (S/N = 3) was 1.8 x 10(-8) g mL(-1), and the relative standard deviation (RSD) was 3.0% (n = 11) for 1.4 x 10(-6) g mL(-1). The proposed method had been successfully applied to the determination of 2,4-DCP in river water.

In the presence of carbonate and uranine, the chemiluminescent intensity from the reaction of luminol with hydrogen peroxide was dramatically enhanced in a basic medium. Based on this fact and coupled with the technique of flow-injection analysis, a highly sensitive method was developed for the determination of carbonate with a wide linear range. The method provided the determination of carbonate with a wide linear range of 1.0 x 10(-10)-5.0 x 10(-6) mol L(-1) and a low detection limit (S/N = 3) of carbonate of 1.2 x 10(-11) mol L(-1). The average relative standard deviation for 1.0 x 10(-9)-9.0 x 10(-7) mol L(-1) of carbonate was 3.7% (n = 11). Combined with the wet oxidation of potassium persulfate, the method was applied to the simultaneous determination of total inorganic carbon (TIC) and total organic carbon (TOC) in water. The linear ranges for TIC and TOC were 1.2 x 10(-6)-6.0 x 10(-2) mg L(-1) and 0.08-30 mg L(-1) carbon, respectively. Recoveries of 97.4-106.4% for TIC and 96.0-98.5% for TOC were obtained by adding 5 or 50 mg L(-1) of carbon to the water samples. The relative standard deviations (RSDs) were 2.6-4.8% for TIC and 4.6-6.6% for TOC (n = 5). The mechanism of the chemiluminescent reaction was also explored and a reasonable explanation about chemical energy transfer from luminol to uranine was proposed.

A nonaqueous capillary electrophoresis (NACE) method, 30 mM ammonium acetate in methanol as background electrolyte (BGE), was developed for separation of the organomercury species without complexing reagents. The effects of different solutes and solvents in BGE were studied. Three species of organomercury, methylmercury, ethylmercury and phenylmercury, were separated well and all the number of theoretical plates were over 106. The present NACE method was also coupled with sample stacking and electrokinetic injection techniques to enhance the detection sensitivity. Under the optimum conditions, the limit of detection (S/N = 3) is 18 ng mL−1 and the linear relation range from 40 to 750 ng mL−1 were obtained for methylmercury.

Cytotoxic activities of jadomycin B and five new jadomycin derivatives against four cancer cell lines (HepG2, IM-9, IM-9/Bcl-2 and H460) were evaluated. Jadomycin S was most potent against HepG2, IM-9 and IM-9/Bcl-2 while jadomycin F was most potent against H460. Their potencies correlated with the degrees of apoptosis induced. Structure-activity-relationship analyses clearly demonstrate that the side chains of the oxazolone ring derived from the incorporated amino acids make a significant impact on biological activity. Therefore, jadomycin offers an ideal scaffold to manipulate structure and could be exploited to make many novel bioactive compounds with altered activities.

Using As2 as an arsenic source together with other appropriate growth and annealing procedures, we have improved the electrical and magnetic properties of GaMnAs films and obtained Curie temperatures as high as 159 K. For Mn concentrations up to 7%, we have demonstrated that the compensation previously observed in such films is mainly due to Mn interstitials, which can be removed by using appropriate annealing procedures for thin films. For the Mn concentrations >7%, we suggest that additional AsGa defects also cause compensation, which cannot be removed by our present annealing procedure.

Large quantities of gallium nitride (GaN) nanorods have been synthesized via direct reaction of metallic gallium vapor with flowing ammonia at 970 °C in a quartz tube. The nanorods have been confirmed as crystalline wurzite GaN by powder X-ray diffraction, selected-area electron diffraction and X-ray photoelectron spectrometry. Transmission electron microscopy and scanning electron microscopy reveal that the nanorods are straight and uniform, with diameters ranging from 40 nm to 150 nm and lengths up to hundreds of micrometers. The growth mechanism is discussed briefly. Photoluminescence measurements on bulk GaN nanorods at room temperature show two strong peaks at 377 nm (3.28 eV) and 360 nm (3.44 eV) attributed to the zero-phonon donor-acceptor pair transition and the donor-bound exciton, respectively.

Background 5,10-methylenetetrahydrofolate reductase (MTHFR) variants, C677T and A1298C, have been reported to be associated with decreased risk of acute lymphoblastic leukemia (ALL). However, results derived from individually underpowered studies are conflicting. We carried out an updated meta-analysis on the association between MTHFR polymorphisms and ALL risk. Methods Relevant publications were searched through PUBMED and EMBASE databases. The associations between MTHFR C677T and A1298C polymorphisms and the risk of ALL were evaluated by odds ratios (ORs). The heterogeneity and publication bias were estimated. Meta-regression analysis was performed to evaluate the potential sources of heterogeneity. Results C677T polymorphism was associated with a reduced risk of ALL (allele contrast: ORRE = 0.91, 95% CI: 0.83-0.99). Subgroup analysis showed MTHFR C677T variant was associated with decreased susceptibility to ALL in children and Caucasians. Meta-regression showed the logOR for the association between T allele and ALL increased as sex ratio (M/F) in the case group increased (P = 0.01). Regarding A1298C polymorphism, no significant association was observed (allele contrast: ORRE = 1.01, 95% CI: 0.91-1.11). There was no publication bias for C677T or A1298C polymorphism. Conclusions The present meta-analysis suggests that the C677T polymorphism, not A1298C, in MTHFR gene is associated with a decreased risk of ALL, particularly among children and Caucasians subjects. Our findings suggest that the influence of the C677T polymorphism on ALL susceptibility is modified by sex ratio in cases (M/F). Since folate intake may be a possible confounding factor, including this factor in future prospective studies is warranted. Further meta-analysis studies should be at least stratified for folate levels and gender to give more powerful and informative results.

A new oral delivery system, polybutylcyanoacrylate nanoparticles (PBCNs), was introduced to improve the oral bioavailability of curcumin (CUR), a poorly soluble drug. The formulation was optimized by orthogonal design and the optimal PBCNs loading CUR exhibited a spherical shape under transmission electron microscopy with a range of 40–400 nm. Physicochemical state of CUR in PBCN was investigated by X-ray diffraction and the possible structure changes occurring in CUR after conjugating with polybutylcyanoacrylate were studied with FTIR. The results indicated that CUR in PBCN was in a non-crystalline state and CUR was encapsulated in PBCN without chemical reaction. The oral pharmacokinetic study was conducted in rats and the relative bioavailability of CUR encapsulated PBCNs to the crude CUR was more than 800%. The in situ absorption experiment in rat intestine indicated the absorption was first order with passive diffusion mechanism. The absorption results in various segments of intestine showed that the main absorption sites were ileum and colon. It can be concluded that PBCNs as an oral carrier can significantly improve the oral absorption of a poorly soluble drug.

The influence of sample orientation and polarity on the blue emission from As-doped GaN layers grown by plasma-assisted molecular beam epitaxy (PA-MBE) was investigated. Arsenic doped GaN layers were grown under identical PA-MBE conditions on several types of substrates including c-plane (0001) sapphire and polar and non-polar GaN templates grown by metal-organic vapour phase epitaxy (MOVPE). Non-polar GaN MOVPE templates were grown on aplane (11–20) sapphire and LiAlO2 (100). The orientation and polarity have a strong influence on the morphology and the optical properties of As-doped GaN layers. Strong blue emission from As-doped GaN was observed only in the case of (000–1) oriented N-polarity layers.

GaN layers periodically-doped with arsenic were grown by plasma-assisted molecular beam epitaxy on sapphire substrates. Secondary ion mass spectroscopy studies using different secondary ions clearly confirmed the existence of As-modulation in the GaN/GaN:As periodically-doped structures, however, the degree of As-modulation is still under discussion. The use of modulation doping with As has a strong influence on the optical properties of GaN/GaN:As structures.