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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.

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.

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.

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.

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.

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.

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.

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.

Using site-directed mutagenesis and steady-state kinetic measurements, the functional role of the conserved glycine 127 in a human vaccinia H1-related phosphatase (VHR) was investigated. The mutations of Gly127 to Ala and Pro resulted in a significant decrease in k(cat)/K(m), and increase in K(i) for arsenate, indicating that flexibility at the Gly127 site has a large effect on substrate binding and catalytic activity. No substantial decrease in k(cat)/K(m) and increase in K(i) values were observed for G127 deletion mutant. This showed the conformational flexibility of the PTP loop also affected the enzymatic activity of VHR. Our data suggest that the flexibility of the PTP loop in VHR is probably controlled by Gly127, and that even subtle changes in the loop flexibility may interfere with substrate binding and enzymatic reaction.

Transient left ventricular dysfunction can occur after hypothermic, hyperkalemic cardioplegic arrest and is associated with decreased beta-adrenergic receptor responsiveness. Occupancy of the beta-adrenergic receptor activates adenylate cyclase, which phosphorylates the L-type Ca2+ channel-enhancing myocyte contractility. The goal of this study was to identify potential mechanisms that contribute to the defects in the beta-adrenergic receptor signaling cascade after cardioplegic arrest.Isolated left ventricular porcine myocytes were assigned to one of two treatment groups: (1) cardioplegic arrest (24 mEq/L K+, 4 degrees C x 2 hours, then 5 minutes in 37 degrees C cell media; n = 130) or (2) normothermic control (cell media, 37 degrees C x 2 hours; n = 222). Myocyte contractility was assessed at baseline and after either beta-adrenergic receptor occupancy (25 nmol/L isoproterenol [INN: isoprenaline]), activation of adenylate cyclase (0.5 mumol forskolin), or direct activation of the L-type Ca(2+)-channel (10 nmol/L or 100 nmol/L (-)BayK 8644).Myocyte velocity of shortening (micron/sec) was increased with beta-adrenergic receptor occupancy or direct adenylate cyclase stimulation compared with baseline in the normothermic group (187.3 +/- 6.9, 181.7 +/- 10.2, and 73.9 +/- 2.9, respectively; p0.0001) and after cardioplegic arrest (128.6 +/- 8.9, 124.3 +/- 9.4, and 46.1 +/- 2.6, respectively; p0.0001). However, the response after cardioplegic arrest was significantly reduced compared with normothermic values under all conditions (p = 0.012). Direct activation of the L-type Ca(2+)-channel, which eliminates beta-adrenergic receptor-dependent events, increased myocyte contractility in the normothermic group (161.90 +/- 12.0, p0.0001) and after cardioplegic arrest (92.78 +/- 6.8, p0.0001), but the positive inotropic response appeared reduced compared with normothermic control values (p = 0.003).These findings suggest that contributory mechanisms for the reduced beta-adrenergic receptor-mediated response after hypothermic, hyperkalemic cardioplegic arrest lie downstream from these specific components of the transduction pathway and likely include defects in Ca2+ homeostasis, myofilament Ca2+ sensitivity, or both.

Campylobacter jejuni is a food-borne bacterial pathogen that possesses two distinct hemoglobins, encoded by the ctb and cgb genes. The former codes for a truncated hemoglobin (Ctb) in group III, an assemblage of uncharacterized globins in diverse clinically and technologically significant bacteria. Here, we show that Ctb purifies as a monomeric, predominantly oxygenated species. Optical spectra of ferric, ferrous, O(2)- and CO-bound forms resemble those of other hemoglobins. However, resonance Raman analysis shows Ctb to have an atypical nu(Fe)(-)(CO) stretching mode at 514 cm(-)(1), compared to those of the other truncated hemoglobins that have been characterized so far. This implies unique roles in ligand stabilization for TyrB10, HisE7, and TrpG8, residues highly conserved within group III truncated hemoglobins. Because C. jejuni is a microaerophile, and a ctb mutant exhibits O(2)-dependent growth defects, one of the hypothesized roles of Ctb is in the detoxification, sequestration, or transfer of O(2). The midpoint potential (E(h)) of Ctb was found to be -33 mV, but no evidence was obtained in vitro to support the hypothesis that Ctb is reducible by NADH or NADPH. This truncated hemoglobin may function in the facilitation of O(2) transfer to one of the terminal oxidases of C. jejuni or, instead, facilitate O(2) transfer to Cgb for NO detoxification.

Fe-S/γ-Al2O3 was prepared by thermally decomposing Fe(CO)5 onto γ-Al2O3 and subsequent sulphurisation with sublimed sulphur in a magnetically stirred autoclave and used as the catalyst for catalytic hydroconversion (CHC) of Lingwu bituminous coal (LBC). Non-catalytic hydroconversion (NCHC) and CHC of LBC were conducted in cyclohexane under 5 MPa of initial hydrogen pressure at 300°C. The reaction mixtures were extracted with petroleum ether and analysed with a gas chromatography/mass spectrometer. The results show that Fe-S/γ-Al2O3 significantly catalysed the formation of hydroarenes, arenes and arenols and completely removed 2,5-dimethylthiophene from LBC.

How glucose is metabolized can influence cell function, but whether differences in glucose metabolism reflect, or dictate, cell state is not clear and is of particular interest given the association of cancer with aerobic glycolysis. Studies on cancer cell lines have indicated that increased glucose uptake with lactate production regardless of oxygen concentration, a phenomenon also known as the Warburg effect, is promoted in part by expression of the M2 isoform of pyruvate kinase (PKM2) and the muscle form of lactate dehydrogenase A (LDHA). Normal somatic cells thought to also preferentially use glycolytic metabolism are tissue stem cells, particularly the self-renewing hematopoietic stem cells (HSC) resident in the hypoxic microenvironment of the bone marrow. It remains to be defined, however whether proliferating hematopoietic progenitor cells rely on aerobic glycolysis and whether malignant and normal hematopoietic cells are dependent on the same metabolic regulation. We observed that PKM2 and LDHA are the predominant isoforms expressed by all BM hematopoietic cells. To further understand the role of glycolytic metabolism in hematopoiesis and hematological malignancy, we utilized a mouse strain that allows conditional deletion of the PKM2 specific exon 10. Deletion of PKM2 in hematopoetic cells leads to expression of PKM1, accompanied with partial inhibition of lactate production and decreased glycolytic intermediates in the hematopoietic stem/progenitor cell (HSPC) population. Loss of PKM2 compromises the long-term repopulation capacity of HSPCs as revealed by serial transplantation assay. Interestingly, the repopulating defects resulting from PKM2 depletion appear to involve progenitors, perhaps due to inadequate biomass generation necessary for robust cell proliferation. To confirm that the effect of PKM2 deletion on HSPC function is due to metabolic changes rather than other putative PKM2 functions, we engineered a mouse strain that allowed conditional knockout of LDHA to more potently impair aerobic glycolysis. LDHA deletion completely inhibited lactate production, enhanced ROS levels in hematopoietic cells and impaired long-term BM repopulating activity. In contrast to PKM2 deletion that affects progenitor but not stem cells, LDHA depletion impacts both stem cell maintenance and progenitor cell proliferation. Deletion of either PKM2 or LDHA markedly suppressed leukemia initiation by either putative stem cell (BCR-ABL) or progenitor (MLL-AF9) transforming alleles. Therefore, modulating aeroblic glycolysis has effects on normal hematopoietic cells that depend upon cell state and negatively impacts leukemic growth regardless of cell state. The differential sensitivity of normal and malignant cells to modulation of aerobic glycolysis suggests a potential therapeutic opportunity for leukemia intervention. Disclosures: No relevant conflicts of interest to declare.