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In this paper, we demonstrate an intensity-tunable THz bandpass filter by introducing liquid crystal (LC) integrated with asymmetric frequency selective surface (FSS) and subwavelength metal gratings. Here, the tunable THz filter is derived from the inner polarization state conversion in composited devices, and the incident linear polarization can be converted into 90° orthogonal components. By controlling the LC orientation under the applied electric field with the metamaterial electrodes, the polarization conversion process can be actively modulated; thus, the polarization-dependent and tunable THz bandpass filter is achieved. Based on the multilayer design and the inner Fabry–Perot-like resonance mechanism, the LC-integrated metamaterials filter presents better filtering performance than the single FSS filter, and the Q -value is improved from 7.7 to 13.8 at the working frequency. Our simulated work paves the way for the design of new and efficient THz filters.

Toroidal dipole response in metamaterials was usually based on a complex structure with special arrangements or symmetries. In this paper, we propose an asymmetric double-disk metamaterial to numerically and experimentally demonstrate the toroidal dipole response in microwave frequency range. When the upper disk has an offset angle θ ranging from 0 to 100 degrees with respect to the lower one, the toroidal dipole resonance always plays the decisive role, which has been proved by calculating the scattered power in terms of the multipole scattering theory. Besides, the dependence of toroidal dipole response on structural parameters has been explored. Our works enrich the research of toroidal moment and, meanwhile, present more application potentials in meta-devices from microwave to optical regime.

Taking advantage of the flexible customization of dynamic and Pancharatnam–Berry phases on meta-atoms, spin-decoupled multifunctional metasurfaces have been realized for optical beams of orthogonal circularly polarized lights, which promotes the diverse development of nanophotonic devices. To date, spin-decoupled metasurfaces can only spatially split and deflect beams in coplanar directions not in non-coplanar, limiting further applications. Here, a single metasurface is proposed to experimentally as well as numerically demonstrate the spin-decoupled omnidirectional anomalous refraction. The results indicate that the three-dimensionally omnidirectional dual-beam refractions are attributed to arbitrary engineering of spin-independent phase gradients along any in-plane orientations of the single metasurface. It is believed that the proposed spin-decoupled omnidirectional metasurfaces are promising candidates for multifunctional applications in compact spin-based nanophotonic systems, such as polarized beam splitting, steering, and polarimeter.

Background Toxoplasma gondii is an intracellular protozoan that can infect humans and other animals, including cattle. Cattle are one of the world’s main sources of meat, and people who consume raw or undercooked meat and milk of cattle infected with T. gondii can become infected. In this study, a total of 5292 dairy cattle serum samples, collected from 17 cities (Henan Province, China) from January 2015 to September 2017, were screened for antibodies against T. gondii. Results Antibodies to T. gondii were found in 1.93% (102/5292) (95% CI, 1.56–2.30) of dairy cattle using a modified agglutination test (cut-off 1:100). The results showed that geographic location and season may be risk factors for T. gondii infection of cattle (P

A bi-layer continuous omega-shaped metamaterial was proposed and fabricated to measure the asymmetric transmission (AT) effect of a linearly polarized light at near-infrared region. The metamaterial was fabricated by the electron-beam lithography method, and the AT effect was demonstrated by the difference between total transmittances in the two opposite propagation directions for x-/y-polarized incident light. The experimental results were confirmed by the full-wave simulated results. Importantly, we also experimentally demonstrated that the AT effect is robust against the misalignments between the first and the second omega-shaped layers. Accordingly, the successfully prepared sample and its characterization provide a bright future for applications in light-controlled switchers and optical diodes in on-chip optical systems and information communication systems.

We experimentally and theoretically investigate Fano-like resonance in a large-area Au/SiO2/Au nano-patches meta-structure, which originates from the coupling between Fabry–Perot resonance and magnetic dipole resonance modes. A highly sensitive refractive index sensor based on the lineshape analysis is obtained. The extracted wavelength shift with the amount of substance of Hg2+ changing from 10–3 pmol to 1 nmol has a linear dependence, and the sensitivity can reach to ultra-low limit of detection (LOD) as 10–3 pmol. This study may provide an approach for the development and modification in sensing.

This study proposes a bi-layer windmill-shaped metamaterial that consists of resonators, with similar shapes, on both sides of a dielectric substrate. In this study, the second layer is rotated clockwise around the substrate normal at 90° and thereafter flipped in the first layer. Due to the introduction of a windmill-like shape, the resonant structures result in new resonant modes and thus can achieve multi-band high-efficiency cross-polarization conversions and asymmetric transmissions (ATs) for a linearly polarized incident plane wave with a maximum asymmetric parameter of 0.72. Depending on the geometric parameters of our windmill-shaped structures, the AT effect scan be flexibly modulated in a broad multi-band from 160 THz to 400 THz, which has not been reported in previous studies. These outstanding AT effects provide potential applications in optical diodes, polarization control switches, and other nano-devices.

Survival and outcome of cardiac arrest (CA) are dismal despite improvements in cardiopulmonary resuscitation (CPR). Salvianolic acid B (Sal B), extracted from Salvia miltiorrhiza, has been investigated for its cardioprotective properties in cardiac remodeling and ischemic heart disease, but less is known about its role in CA. The aim of this study was to learn whether Sal B improves cardiac and neurologic outcomes after CA/CPR in mice. Female C57BL/6 mice were subjected to eight minutes of CA induced by an intravenous injection of potassium chloride (KCl), followed by CPR. After 30 seconds of CPR, mice were blindly randomized to receive either Sal B (20 mg/kg) or vehicle (normal saline) intravenously. Hemodynamic variables and indices of left ventricular function were determined before CA and within three hours after CPR, the early postresuscitation period. Sal B administration resulted in a remarkable decrease in the time required for the return of spontaneous circulation (ROSC) in animals that successfully resuscitated compared to the vehicle-treated mice. Myocardial performance, including cardiac output and left ventricular systolic (dp/dtmax) and diastolic (dp/dtmin) function, was clearly ameliorated within three hours of ROSC in the Sal B-treated mice. Moreover, Sal B inhibited CA/CPR-induced cardiomyocyte apoptosis and preserved mitochondrial morphology and function. Mechanistically, Sal B dramatically promoted Nrf2 nuclear translocation through the downregulation of Keap1, which resulted in the expression of antioxidant enzymes, including HO-1 and NQO1, thereby counteracted the oxidative damage in response to CA/CPR. The aforementioned antiapoptotic and antioxidant effects of Sal B were impaired in the setting of gene silencing of Nrf2 with siRNA in vitro model. These improvements were associated with better neurological function and increased survival rate (75% vs. 40%, p<0.05) up to 72 hours postresuscitation. Our findings suggest that the administration of Sal B improved cardiac function and neurological outcomes in a murine model of CA via activating the Nrf2 antioxidant signaling pathway, which may represent a novel therapeutic strategy for the treatment of CA.

Extraction residue from Geting bituminous coal (ER GBC ) via ultrasonic extraction with isometric carbon disulfide/acetone binary solvent was subjected to thermal dissolution (TD), thermal dissolution under pressurized nitrogen (TDN), non-catalytic hydroconversion (NCHC), and catalytic hydroconversion (CHC) in cyclohexane at 300 °C for 3 h. The catalyst was prepared by thermally decomposing Fe(CO) 5 and Ni(CO) 4 onto γ-Al 2 O 3 . The reaction mixtures from TD, TDN, NCHC, and CHC were sequentially extracted with petroleum ether, carbon disulfide, methanol, acetone, and isometric acetone/carbon disulfide binary solvent to afford extracts 1–5 (E 1 –E 5 ). Detailed characterizations of the extracts were performed with a gas chromatography/mass spectrometer (GC/MS) and Fourier transform infrared spectrometer. The results show that the yields of E 1 and E 3 from CHC are appreciably higher than those from others, suggesting the great influence of CHC on the breakage of -CH 2 - and -O- linkages connected to condensed aromatic rings. According to analysis with GC/MS, alkanes and arenes are the most abundant species in each E 1 , in which most of the arenes are methylarenes. Arenols and phthalates are the predominant oxygen-containing organic compounds. Arenes with 1 or 2 ring(s) markedly increase by using H 2 , especially in the presence of the catalyst. The H . catalytically generated over FeNi–S/γ-Al 2 O 3 and the stabilizing effect of H 2 on the generated radicals could play crucial roles in cleaving bridged linkages connected to condensed aromatic rings and thereby enhance the yields of alkylarenes through NCHC and CHC. Related mechanisms for the formation of some species derived from NCHC and CHC of ER GBC are discussed.

Tracking transplanted stem cells is necessary to clarify cellular properties and improve transplantation success. In this study, we designed and synthesized melanin-based gadolinium3+ (Gd3+ )-chelate nanoparticles (MNP-Gd3+ ) of ∼7 nm for stem cell tracking in vivo. MNP-Gd3+ possesses many beneficial properties, such as its high stability and sensitivity, shorter T1 relaxation time, higher cell labeling efficiency, and lower cytotoxicity compared with commercial imaging agents. We found that the T1 relaxivity (r1 ) of MNP-Gd3+ was significantly higher than that of Gd-DTPA; the nanoparticles were taken up by bone mesenchymal stem cells (BMSCs) via endocytosis and were broadly distributed in the cytoplasm. Based on an in vitro MTT assay, no cytotoxicity of labeled stem cells was observed for MNP-Gd3+ concentrations of less than 800 µg/mL. Furthermore, we tracked MNP-Gd3+ -labeled BMSCs in vivo using 3.0T MRI equipment. After intramuscular injection, MNP-Gd3+ -labeled BMSCs were detected, even after four weeks, by 3T MRI. We concluded that MNP-Gd3+ nanoparticles at appropriate concentrations can be used to effectively monitor and track BMSCs in vivo. MNP-Gd3+ nanoparticles have potential as a new positive MRI contrast agent in clinical applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 131-137, 2017.

Shaerhu subbituminous coal (SSBC) and Mengdong lignite (ML) were extracted with petroleum ether under ultrasonication at room temperature to obtain ESSBC and EML, respectively. The extracts were analyzed with a gas chromatograph/mass spectrometer and a positive-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometer to characterize biomarkers and oxygen-containing species. The biomarkers consist of a homologous series of alkanes and sterenes. The biomarker distributions provide important information on the main origins and microorganism degradation of organic matter in SSBC and ML. Oxygen-containing species, including O2–O4, O2N2, and O1N2 class species, are predominant in the extracts with double bond equivalent (DBE) values of 2–28 and carbon numbers (CNs) of 15–50. The oxygen atoms exist in furan rings, R–O–R′, RCOOR′, and RCOR′ (R and R′ denote an alkyl or aryl group). The species in EML have more varied DBE values and CNs compared with those in ESSBC. Most of the OxN2 (x = 1–2) class species have larger DBE values and CNs than the Ox class species, which might be an evidence for more abundant intermolecular associations, such as hydrogen bonds, among the OxN2 class species than among the Ox class species.

We experimentally investigate the linear polarization conversion for terahertz (THz) waves in liquid crystal (LC) integrated metamaterials, which consist of an LC layer sandwiched by two orthogonally arranged sub-wavelength metal gratings. A Fabry–Perot-like cavity is well constructed by the front and rear gratings, and it shows a strong local resonance mechanism, which greatly enhances the polarization conversion efficiency. Most importantly, the Fabry–Perot-like resonance can be actively tuned by modulating the refractive index of the middle LC layer under the external field. As a result, the integrated metamaterial achieves multi-band tunable linear polarization conversion.

Regulation of STAT3 activation is critical for normal and malignant hematopoietic cell proliferation. Here, we have reported that the endogenous transmembrane protein upstream-of-mTORC2 (UT2) negatively regulates activation of STAT3. Specifically, we determined that UT2 interacts directly with GP130 and inhibits phosphorylation of STAT3 on tyrosine 705 (STAT3Y705). This reduces cytokine signaling including IL6 that is implicated in multiple myeloma and other hematopoietic malignancies. Modulation of UT2 resulted in inverse effects on animal survival in myeloma models. Samples from multiple myeloma patients also revealed a decreased copy number of UT2 and decreased expression of UT2 in genomic and transcriptomic analyses, respectively. Together, these studies identify a transmembrane protein that functions to negatively regulate cytokine signaling through GP130 and pSTAT3Y705 and is molecularly and mechanistically distinct from the suppressors of cytokine signaling (SOCS) family of genes. Moreover, this work provides evidence that perturbations of this activation-dampening molecule participate in hematologic malignancies and may serve as a key determinant of multiple myeloma pathophysiology. UT2 is a negative regulator shared across STAT3 and mTORC2 signaling cascades, functioning as a tumor suppressor in hematologic malignancies driven by those pathways.

The structural features of Zhundong subbituminous coal (ZSBC) were investigated by ruthenium ion-catalyzed oxidation (RICO) and subsequent analyses with a gas chromatograph/mass spectrometer and an atmospheric-pressure solid analysis probe/time of flight-mass spectrometer (ASAP/TOF-MS). The results suggest that condensed aromatic rings linked by short polymethylene bridged linkages, long side chains, and oxygen-containing groups are predominant in ZSBC. Aliphatic bridged linkages connecting 3 aromatic rings also exist in ZSBC. Several heterocyclic carboxylic acids were produced from RICO of ZSBC. The heterocyclic moieties include tetrahydrofuran, pyridine, pyrazole, benzo[b]thiophene, and dithiole rings, suggesting the existence of oxygen-, nitrogen-, and sulfur-containing building blocks in ZSBC. According to analysis with ASAP/TOF-MS, a series of heavier arenecarboxylic acids were detected in the products from RICO of ZSBC and aromatic rings of the heavier arenepolycarboxylic acids include naphthalene, biphenyl, anthracene, phenylnaphthalene, and methyl(phenyl)tetrahydroanthracene, implying that ZSBC contains highly condensed aromatic rings. The existence of chlorine- and bromine-containing moieties was confirmed by the identification of chlorine- and bromine-containing species produced from RICO of ZSBC.

Ruthenium ion-catalyzed oxidation (RICO) of Yanshan petroleum coke (YPC) was performed to characterize condensed aromatics and heteroatomic species in YPC. The analysis with gas chromatograph/mass spectrometer mainly offers information on the distributions of side chain groups and bridged linkages, while the analyses with atmospheric pressure solid analysis probe/time-of-flight mass spectrometer and direct analysis in real time ion source coupled to time-of-flight mass spectrometer complement information on heteroatomic species and highly condensed aromatic moieties in YPC. The results indicate that YPC is rich in highly condensed aromatic moieties with tiny portions of alkyl/alkenyl side chains and alkyl/cycloalkyl bridged linkages. The organic oxygen, nitrogen, and sulfur exist in different aromatic rings (including isobenzofuran-1,3-dione, dioxoisoindoline, phenylquinoline, pyridine, and thiophene rings) and different functional groups (including methoxy, epoxy, nitro, and cyano groups). The formation of fluorine- and chlorine-containing species reveals the existence of fluorine- and chlorine-containing moieties in YPC. In addition, a series of heavier arenecarboxylic acids were produced from RICO of YPC. Their possible aromatic rings could be naphthalene, biphenyl, anthracene, phenanthrene, dihydroanthracene, dihydrophenanthrene, phenylnaphthalene, and methyl(phenyl)tetrahydroanthracene, further confirming the existence of highly condensed aromatic rings in YPC. This investigation provides an effective approach both for value-added utilization and for understanding the structural features of YPC.

Elimination of malignant cells is an unmet challenge for most human cancer types even with therapies targeting specific driver mutations. Therefore, a multi-pronged strategy to alter cancer cell biology on multiple levels is increasingly recognized as essential for cancer cure. One such aspect of cancer cell biology is the relative apoptosis resistance of tumor-initiating cells. Here, we provide an overview of the mechanisms affecting the apoptotic process in tumor cells emphasizing the differences in the tumor-initiating or stem-like cells of cancer. Further, we summarize efforts to exploit these differences to design therapies targeting that important cancer cell population.

FeNi/γ-Al 2 O 3 was prepared by thermally decomposing iron pentacarbonyl and nickel tetracarbonyl onto γ-Al 2 O 3 . Geting bituminous coal (GBC) was subjected to noncatalytic hydroconversion (NCHC) and catalytic hydroconversion (CHC) in the presence of FeNi/γ-Al 2 O 3 and sulfur at 300 °C for 3 h. The reaction mixtures from both NCHC and CHC were fractionated to extracts 1–5 (E 1 –E 5 ) by sequential extraction. The molecular compositions of E 1 –E 5 were characterized with a Fourier transform infrared spectrometer, gas chromatography/mass spectrometer (GC/MS), and atmospheric solid analysis probe/time of flight-mass spectrometer (ASAP/TOF-MS). The results show that the yields of E 1 –E 5 from CHC of GBC are obviously higher than those from NCHC. According to GC/MS analysis, the group components in E 1 from the CHC are dominated by alkanes, arenes, and arenols in remarkable higher yields than those from NCHC, and most of the arenes and arenols are alkyl-substituted ones. The addition of active hydrogen atoms catalytically generated over FeNi–S/γ-Al 2 O 3 to the ipso -position of condensed aromatic rings (CARs) in GBC could play a crucial role in cleaving–CH 2 − and–O − linkages connected to the CARs and thereby enhanced the yields of alkylarenes and alkylarenols through CHC. Meanwhile, the partial hydrogenation of some CARs during CHC could promote the radical hydrogen transfer along with thermal rupture of some relatively strong bonds to produce soluble molecules. According to ASAP/TOF-MS analysis, the soluble species from both NCHC and CHC have molecular mass distributions ranging from 100 to 500 u . A series of polar and/or involatile organic species.

Two Chinese coals, Shengli lignite and Shenmu–Fugu subbituminous coal, were subjected to non-catalytic hydroconversion (NCHC) and catalytic hydroconversion (CHC) in cyclohexane at 300 °C for 3 h under pressurized hydrogen using a solid acid as the catalyst, which was prepared by impregnating isometric pentachloroantimony and trimethylsilyl trifluoromethanesulfonate into an activated carbon. The reaction mixtures from both NCHC and CHC were sequentially extracted with petroleum ether, carbon disulfide, methanol, acetone, and isometric acetone/carbon disulfide mixed solvent to afford extracts 1–5 (E 1 –E 5 ). The results show that both E 1 and total extract yields from CHC are appreciably higher than those from NCHC of each coal. E 1 from either NCHC or CHC of each coal was analyzed with a gas chromatograph/mass spectrometer (GC/MS) and an atmospheric solids analysis probe/time of flight mass spectrometer (ASAP/TOF-MS). GC/MS analysis shows that each E 1 consists of alkanes, arenes, and oxygen-containing organic compounds (OCOCs), and most of the arenes are methyl-substituted ones, whereas alkenyl groups only appear on benzene ring; most of the OCOCs are arenols, especially alkylarenols. According to ASAP/TOF-MS analysis, organic compounds with molecular masses ranging from 500 to 950 u appear in E 1 from CHC of both coals.

Production of the cells that ultimately populate the thymus to generate α/β T cells has been controversial, and their molecular drivers remain undefined. Here, we report that specific deletion of bone-producing osteocalcin (Ocn)-expressing cells in vivo markedly reduces T-competent progenitors and thymus-homing receptor expression among bone marrow hematopoietic cells. Decreased intrathymic T cell precursors and decreased generation of mature T cells occurred despite normal thymic function. The Notch ligand DLL4 is abundantly expressed on bone marrow Ocn+ cells, and selective depletion of DLL4 from these cells recapitulated the thymopoietic abnormality. These data indicate that specific mesenchymal cells in bone marrow provide key molecular drivers enforcing thymus-seeding progenitor generation and thereby directly link skeletal biology to the production of T cell–based adaptive immunity.

Optical activity has been demonstrated by twisting cascading multilayer anisotropic metamaterials with cross-polarization conversions, for which the x-(y-) polarized light is significantly transformed to a y-(x-) polarized one with enhanced transmittance in a unidirectional manner. Here, we design a twisted tri-layer anisotropic metamaterial with the twisted angle θ = 22.5° to present the unidirectional optical activity by linear-to-circular polarization conversions. When the structure is illuminated by x-polarized incident, the x-polarized light is converted to a right-circularly polarization for forward transmission at 175.5 THz. But for backward transmission, the x-polarized light is converted to a left-circularly polarization at 350THz. This phenomenon is attributed to the chiral structural arrangement and anisotropic resonance of nanobars. We verify our design at optical frequencies and show potential application in unidirectional circular polarizer and other nanodevices.

The far-field radiation of a single dipolar emitter can be controlled by coupling to toroidal dipole resonance attached to metallic double flat rings, realizing a conversion from non- to super-radiating. The underlying physical mechanism is the hybridization interference of toroidal and electric dipoles under an asymmetric configuration by introducing a radial displacement of the dipolar emitter. By embedding gain medium in the gap spacer between double flat rings, the directional far-field super-radiating power can achieve a tremendous enhancement with a moderate requirement on the gain coefficient, promoting light-matter interaction manipulation.

Xilihaote lignite (XL) and Geting bituminous coal (GBC) were extracted using isometric carbon disulfide/acetone binary solvent at 45°C under microwave irradiation. The raw coals and residues were analyzed with a Fourier transform infrared spectrometer and the extracts with a gas chromatograph/mass spectrometer. The results show that the extract yield of GBC is much higher than that of XL lignite and the molecular composition of the extract from XL is significantly different of that from GBC.

A highly dispersive Fe/ZSM-5 as the precursor of Fe–S/ZSM-5 was prepared by decomposing Fe(CO)5 onto ZSM-5 zeolite at 250 °C. Shengli lignite (SL) was isolated to extractable portion (EP) and extraction residue (ER) by exhaustive extraction with isometric carbon disulfide/acetone mixed solvent (IMCDSAMS) under ultrasonic irradiation. The EP and ER were analyzed with a direct analysis in real time ionization source coupled to ion trap mass spectrometer. Both of them and SL were analyzed with a Fourier transform infrared spectrometer. The ER was subjected to non-catalytic hydroconversion (NCHC) and catalytic hydroconversion (CHC) over Fe–S/ZSM-5, which was formed by in situ reaction of Fe/ZSM-5 with sulfur added, in cyclohexane under pressurized hydrogen at 300 °C. The reaction mixtures were sequentially extracted with petroleum ether, carbon disulfide, methanol, acetone, and IMCDSAMS to afford extracts 1–5 (E1–E5), which were analyzed with a gas chromatography/mass spectrometer (GC/MS). As model reactions, the CHCs of di(1-naphthyl)methane (DNM) and diphenylmethane (DPM) over Fe–S/ZSM-5 were also conducted in cyclohexane at 300 °C. The results show that more than 50% of organic matter in the ER was converted to a soluble portion by the CHC, whereas the yield of soluble portion from the NCHC is only 10.52%. GC/MS-detectable species only appear in the E1, which mainly consists of alkanes, arenes, and arenols either from the NCHC or from the CHC. DNM was selectively hydrocracked to naphthalene and 1-methylnaphthalene over Fe–S/ZSM-5, while DPM hydrocracking did not proceed, indicating that Fe–S/ZSM-5 catalyzed the formation of radical hydrogen from molecular hydrogen and subsequent radical hydrogen transfer (RHT) to the ipso-position of naphthalene ring in DNM. Some CH2 and O in the ER could be connected to condensed aromatic rings (CARs). Analogously, RHT to the ipso-position of CARs in the ER resulted in the release of arenes and phenols from the ER.

The balance between oxidative and non-oxidative glucose metabolism is essential for a number of pathophysiological processes. By deleting enzymes that affect aerobic glycolysis with different potencies, we examine how modulating glucose metabolism specifically affects hematopoietic and leukemic cell populations. We find that deficiency in the M2 pyruvate kinase isoform (PKM2) reduces levels of metabolic intermediates important for biosynthesis and impairs progenitor function without perturbing hematopoietic stem cells (HSC), whereas lactate dehydrogenase-A (LDHA) deletion significantly inhibits the function of both HSC and progenitors during hematopoiesis. In contrast, leukemia initiation by transforming alleles putatively affecting either HSC or progenitors is inhibited in the absence of either PKM2 or LDHA, indicating that the cell state-specific responses to metabolic manipulation in hematopoiesis do not apply to the setting of leukemia. This finding suggests that fine-tuning the level of glycolysis may be therapeutically explored for treating leukemia while preserving HSC function., National Institutes of Health (U.S.) (Grants P30CA147882 and R01CA168653), Smith Family Foundation, Burroughs Wellcome Fund, Virginia and D.K. Ludwig Fund for Cancer Research, Damon Runyon Cancer Research Foundation

Ruthenium ion-catalyzed oxidation (RICO) of Huolinguole lignite (HL) was performed to understand the structural features of macromolecular aromatic species in HL by analyzing the resulting soluble species (SSs) with a gas chromatography/mass spectrometer and atmospheric-pressure solids-analysis probe/time of flight-mass spectrometer. The results show that in the SSs, alkanedioic acids are predominantly abundant and most of them are succinic acid and glutaric acid, indicating that HL is rich in bridged linkages (BLs) and CH2CH2 and CH2CH2CH2 are the main BLs connecting aromatic rings. The total yield of benzenecarboxylic acids with less carboxylic groups (CGs) (the number of CGs

Rice husk powder was oxidized in aqueous sodium hypochlorite solution under mild conditions with different reaction times. Fourier transform infrared spectroscopy, gas chromatography-mass spectrometry (GC-MS), and direct analysis in real time-mass spectrometry (DART-MS) were used to analyze the oxidation products. Results showed that oxidation was a feasible way to depolymerize the macromolecules in the biomass and convert hydroxyl groups to carboxyl groups. In total, 113 organic compounds in oxidation products with molecular mass less than 500 Da were identified using GC-MS. As an ambient ionization technique, DART-MS was applied to the determination of biomass derivatives and revealed mass distribution and molecular structure information for the rice husk oxidation products.

This study is to construct a rapid and effective method for identification of wild and cultivated Glycyrrhiza uralensis (hereinafter referred to as Glycyrrhizae Radix et Rhizoma) from Ningxia by comparison of the difference in chromatography identification based on index components and near-infrared spectroscopy identification. HPLC and UV methods were used to determine the content of liquiritin, glycyrrhizate and total flavonoids for 9 wild Glycyrrhizae Radix et Rhizoma and 14 cultivated Glycyrrhizae Radix et Rhizoma samples,and the near-infrared spectroscopy was also,collected. The results illustrated that the chromatography identification based on index components could not identify wild and cultivated Glycyrrhizae Radix et Rhizoma from Ningxia, while near-infrared spectroscopy could quickly and effectively achieve it. It provides an effective method for the growth pattern identification and application of Glycyrrhizae Radix et Rhizoma.

Tracking transplanted stem cells is necessary to clarify cellular properties and improve transplantation success. In this study, we designed and synthesized melanin-based gadolinium

Three catalysts were prepared by impregnating the same volume of pentachloroantimony (PCA), trimethylsilyl trifluoromethanesulfonate (TMSTFMS), or isometric PCA and TMSTFMA into an activated carbon (AC). Di(1-naphthyl)methane (DNM) was used as a coal-related model compound to evaluate their catalytic activity. The results show that C ar C alk bond in DNM can be specifically cleaved over each catalyst to afford naphthalene and 1-methylnaphthalene under pressurized hydrogen at temperatures up to 300 °C, but as a new solid acid (NSA), PCA–TMSTFMS/AC is significantly more active for DNM hydrocracking than the other two catalysts. FTIR and SEM analyses reveal the strong interactions among PCA, TMSTFMS, and the AC in the NSA. NH 3 -TPD analysis suggests that the NSA should exhibit appreciably stronger acidity than the other two catalysts. The strong interactions may result in the appreciably stronger acidity of the NSA than that of the other two catalysts and thereby facilitate DNM hydrocracking. It is presumed that H 2 was heterolytically cleaved to immobile H − and mobile H + . The addition of mobile H + to ipso -position of DNM should be crucial step for DNM hydrocracking.

with the rapid development of national economy, the construction of our country and technical personnel requirements also produced corresponding changes, the demand for interdisciplinary talents gradually increased to the higher education has put forward higher requirements. The direction of the civil engineering course reform is changed to "large civil specialty” as the basic starting point, combine with the reform of talented person training mode, adjust the students' knowledge structure. The task of introduction to civil engineering is to cultivate the students' awareness of civil engineering major, make low grade students understand the civil engineering involved in the field of the content, methods, achievements and development situation about civil engineering comprehensive from the visual angle of safe academics, social and security technology, economy and management unity. The new understanding of civil engineering specialty, enhances the student to study the interest of engineering knowledge, broaden their knowledge. According to the positioning of the course, in the teaching process optimization of teaching materials, reasonable allocation of hours, adopt the suitable way of teaching organization teaching, and achieve good teaching results

The water conservancy hydroelectric construction engineering major is establishing an operate in the reform in education and the course, should develop craft advantage, the tapping has the development scheme of the talented person of oneself special feature and quickly takes occupation capability as the course system of nucleus to construct and reform to practice teaching system, intensifies a student to practice to begin capability development and arouses a completely developing of the reform in education; Set up to practice the teaching mass guarantee system, intensify the construction of solid Xun matrix, the reform fulfillment teaching investigates a method, values to produce to learn wedge bonding and speeds the construction of high character teacher's troops. The teaching plans the reform of teaching mode talented person the key of development mode reform at, come out an and profession close correlation, foster a deluxe application person just new road son

The generation of a B cell repertoire involves producing and subsequently purging autoreactive B cells. Receptor editing, clonal deletion and anergy are key mechanisms of central B cell tolerance. Somatic mutation of antigen-activated B cells within the germinal center produces a second wave of autoreactivity; but the regulatory mechanisms that operate at this phase of B cell activation are poorly understood. We recently identified a post germinal center tolerance checkpoint, where receptor editing is re-induced to extinguish autoreactivity that is generated by somatic hypermutation. Re-induction of the recombinase genes RAG1 and RAG2 in antigen-activated B cells requires antigen to engage the B cell receptor and IL-7 to signal through the IL-7 receptor. We demonstrate that this process requires IL-6 to upregulate IL-7 receptor expression on post germinal center B cells. Diminishing IL-6 by blocking antibody or haplo-insufficiency leads to reduced expression of the IL-7 receptor and RAG and increased titers of anti-DNA antibodies following immunization with a peptide mimetope of DNA. The dependence on IL-6 to initiate receptor editing is B cell intrinsic. Interestingly, estradiol decreases IL-6 expression thereby increasing the anti-DNA response. Our data reveal a novel regulatory cascade to control post germinal center B cell autoreactivity.

How self tolerance is maintained during B cell development in the bone marrow has been a focal area of study in immunology. Receptor editing, anergy and clonal deletion all play important roles in the regulation of autoimmunity in the immature population. The mechanisms of tolerance induction in the periphery, however, are less well characterized. Overexpression of the apoptosis inhibitor Bcl-2 rescues autoreactive B cells from deletion and can contribute to the development of autoimmune disease in certain genetic backgrounds. Using a peptide induced autoimmunity model, we recently identified a peripheral tolerance checkpoint in antigen-activated B cells that have undergone class switching and somatic hypermutation. At this checkpoint, receptor editing, induced by antigen engagement, dampened the autoantibody response. In this study, we show that receptor editing fails to be induced in antigen activated DNA-reactive B cells that overexpress Bcl-2 (Bcl-2 Tg). The failure to induce RAG and receptor editing is likely due, at least partially, to the lack of self antigen. First, the levels of circulating DNA and of apoptotic bodies in the spleen of Bcl-2 Tg mice are significantly lower than in control mice. Second, in Bcl-2 Tg mice, RAG can be induced in a population of antigen-activated B cells by providing exogenous soluble antigen. These data suggest that, in addition to its anti-apoptotic activity, Bcl-2 may indirectly inhibit tolerance induction in B cells acquiring anti-nuclear antigen reactivity after peripheral activation by limiting the availability of self antigen.

A new catalyst with two active constituents interacting with activated carbon was prepared. As a model reaction for coal liquefaction, the hydrocracking of di(1-naphthyl)methane (DNM) was investigated under different reaction conditions over the catalyst. The results show that the catalyst converts DNM hydrocraking into 1-methylnaphthalene and naphthalene with high selectively, without any hydrogenation product. Kinetic analysis indicates that DNM hydrocracking in the temperature range of 170-300 °C could be considered as a first order reaction. The activation energy E and pre-exponential factor A for DNM hydrocracking for different reaction times were calculated.

There are many kinds of Ecological-type revetment, including types of Natural vegetation, Masonry, Eco-Concrete and so on. What is more, the engineering characteristics, economic cost, suitable condition of application are all different. Therefore we should choose appropriate types of ecological-type revetment in the construction of river channel for small cities and towns. This article includes the overview of the progress of ecological-type revetment rectification measures, the types and characteristics of ecological-type revetment. Selection principles of economics, security, aesthetics as well as the consideration of the idea of harmonious coexistence between man and water in ecological-type revetment construction are proposed.

In this paper, based on the theoretical analysis and reasonable simplification, one-dimensional mathematical model is presented for the counter-current oxidation of ventilation air methane. The process of counter-current oxidation reaction is simulated by applying the computational fluid dynamics (CFD) software (Fluent), and the effect of the dominating working parameters (such as flow velocity and equivalence ratio and half cycle) are discussed on the temperature and rate of reaction within the counter-current oxidation reaction. The distribution of the temperature field and the reaction rate are simulated when half cycle is 30s, the equivalence ratio is 0.2 and the velocity 0.06 m/s, 0.1m/s and 0.2 m/s. The combustion characteristics are summarized for the device of counter-current oxidation reaction, and the effects of working parameters are analyzed on the burning characteristics. It is so important to increase the combustion efficiency and energy utilization.