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During an exploration of plant pathogens in vegetables occuring in Zhejiang province, China, a novel fungal species, was found. Three strains ZJUP0033-4, ZJUP0038-3 and ZJUP0132 were isolated from black round lesions in the stems and leaves of Amaranthus sp. Phylogenetic analyses based on sequences from four genes including rDNA internal transcribed spacer (ITS), translation elongation factor 1-α (EF1-α), histone (HIS) and β-tubulin (TUB) indicated that D. sinensis clustered in a distinct clade closely related to D. neoarctii, D. angelicae, D. subordinaria, D. arctii, D. cuppatea, D. lusitanicae, D. novem, D. infecunda, D. ganjae and D. manihotia. Morphologically, D. sinensis is distinguished by brown, scattered, globose pycnidia and ellipsoid alpha conidia with bi- to multiguttulate.

To explore the value of unmeasurable enhancement pattern of residual cavity in predicting survival at early stage after gross-total resection in high-grade glioma (HGG) patients. This retrospective study enrolled consecutive 51 HGG patients with unmeasurable enhancement who underwent gross-total resection followed by concurrent chemoradiotherapy and adjuvant chemotherapy. We evaluated the enhancement patterns of residual cavity on contrast-T1WI made within 1 month after tumor resection (20 ± 3 days). The survival state of different enhancement was compared. Thin-linear, thick-linear and nodular enhancement were observed in 22 patients (43%), 10 patients (20%), and 19 patients (37%), respectively. The progression-free survival of patients with thin-linear (487, 151–887 days) was longer than those patients with thick-linear (277, 133–573 days), and nodular enhancement (210, 120–765 days) (P = 0.002). The overall survival of patients with thin-linear (774, 457–1343 days) was longer than those with thick-linear (462, 320–678 days), and nodular enhancement (326, 234–1393 days) (P = 0.002). There was no significant difference of orthogonal value between thick-linear and nodular enhancement (0.854), neither between grade III and IV with same enhancement patterns (P = 0.540, P = 0.720). The unmeasurable enhancement patterns in HGG patients within 1 month after gross-total resection, which might be better than the grade of tumor, holds a potential marker in survival state.

The oxygen reduction reaction (ORR) at iridium single crystalline electrodes, Ir(111) and Ir(332), in 0.1 M HClO 4 and 0.5 M H 2 SO 4 solution, was studied using cyclic voltammetry and potential step chronoamperometry under a hanging-meniscus rotating disk electrode configuration. The results are compared to the ORR behaviors observed on platinum single crystal electrodes with the same surface orientation. We found that i) The kinetics for ORR on Ir(111) are significantly slower than those on Pt(111), the onset potential and half-wave potential for ORR are ca. 100 mV and 370 mV more negative than those on Pt(111), respectively; ii) in 0.1 M HClO 4 only H 2 O 2 is formed on Ir(111) at E > 0.55 V, and when E 2 O, in 0.5 M H 2 SO 4 a significant amount of H 2 O 2 is produced even the potential is as low as 0.15 V; iii) Ir(332) exhibits lower ORR activity than Ir(111), with a half-wave potential that is ca. 30 mV more negative, and the diffusion-limited ORR current is not reached from 0.8 V down to 0.05 V, indicating that at Ir(332), incomplete reduction of O 2 to H 2 O 2 occurs in a wide potential region; iv) significant decay of ORR current with potential scan rate and reaction time in the current transient measurements are observed on both Ir(111) and Ir(332), similar to those observed on Pt(111) and Pt(332) electrodes. The structure-activity relationship of Ir(hkl) toward ORR is discussed.

Layered Cu2MoS4, consisting of earth-abundant elements, is regarded as a potential catalyst for the hydrogen evolution reaction (HER). Herein, we demonstrate a Cu2O-based template strategy to synthesise hierarchical hollow nanostructures of Cu2MoS4. The characterizations reveal that the electrochemically active surface of the hollow Cu2MoS4 is largely enhanced, in contrast to the nanosheet or nanoparticle structures. As the direct outcome, the designed hierarchical hollow structures display excellent HER activities with a low overvoltage and small Tafel slope. This study may provide new inspiration for the research of other ternary sulphide materials as well as subsequently accelerating their applications in the field of catalysis.

The kinetics of the oxidation and reduction of hydrogen peroxide (HPOOR, HPORR) at a Pt electrode in 0.1 M HClO4 + 2 mM H2O2 are investigated by Differential Electrochemical Mass Spectrometry (DEMS) in a flow cell. The O2 mass signal was recorded during cyclic voltammetry, and its potential dependence follows the shape of the cyclic voltammogram. Partial currents for HPOOR and HPORR are estimated based on the O2 mass signal and the total Faradaic current. The onset overpotential for HPORR at the Pt electrode is above 0.6 V. It is limited by the thermodynamics of OHad desorption, as is also the case with ORR. The onset overpotential for HPOOR is below 0.1 V, due to the faster consumption of H2O2 through HPORR at these potentials and the small bulk H2O2 concentration used. Keywords: Hydrogen peroxide oxidation reaction (HPOOR), Hydrogen peroxide reduction reaction (HPORR), Differential electrochemical mass spectrometry (DEMS), Mixed potential effect, Reaction kinetics

Shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) is employed to investigate the electrochemical behavior of adenine molecules on smooth Ag electrodes. To attain this goal, pinhole-free shell-isolated Ag nanoparticles (Ag SHINs) have been synthesized and then used as signal “amplifiers” in the gap-mode configuration (Ag SHINs are coupled with a Ag electrode surface). The as-prepared Ag SHINs exhibit remarkable plasmonic performance under 488, 532, and 633 nm excitations as revealed by finite-difference time-domain (FDTD) simulations and SHINERS experiments. Furthermore, wavelength-dependent SHINERS investigation of adenine on Ag electrodes is excellently combined with the electrochemical technique. With outstanding chemical stability and plasmonic property, the Ag SHINs are extraordinarily suitable for fundamental studies at various electrochemical interfaces.

A simple and green approach to synthesize highly active electro-catalysts for methanol oxidation reaction (MOR) without using any organic agents is described. Pt nanoparticles are directly deposited on the pre-cleaned and pre-oxidized multiwall carbon nanotubes (MWC-NTs) from Pt salt by using CO as the reductant. MOR activity has been characterized by both cyclic voltammetry and chronoamperometry, the current density and mass specific current at the peak potential (ca. 0.9 V vs. RHE) reaches 11.6 mA/cm2 and 860 mA/mgPt, respectively. After electro-deposition of Ru onto the Pt/MWCNTs surface, the catalysts show steady state mass specific current of 20 and 80 mA/mgPt at 0.5 and 0.6 V, respectively.

The interaction of CO, HCOOH, HCHO, and CH3OH molecules with a Pt surface initially covered with a layer of oxide under open circuit potential (OCP) is studied by combined infrared and mass spectroscopy. We found that after switching to the fuel containing solution and concomitantly switching off the electrode potential control at 1.2 V, (i) the OCP decays from 1.2 V down to values of 0.58 V (CO), 0.12 V (HCOOH), 0.08 V(HCHO) and 0.24 V(CH3OH); (ii) CO is the only adsorbate formed at the Pt surface from the fuels; (iii) the rates for the decay of OCP and for the buildup of COad adlayer decrease in the order of CO > HCHO > HCOOH > CH3OH; (iv) the rate of CO2 production and the total amount of CO2 produced decreases in the order of CO > HCOOH > HCHO > CH3OH; and (v) a significant amount of HCOOH is formed for the case with HCHO and the main by product from CH3OH is HCHO. Our results indicate that (i) the change in OCP is determined by the change of net charge at the electrode/electrolyte interface due to th...

O2 concentration near Pt surface during oxygen reduction reaction (ORR) in 0.1 M HClO4 has been monitored by rotating ring-disk electrodes system. At 0.8 V 400 rpm. At E > 0.8 V accumulation of Oad|OHad at Pt disk electrode with ORR time is evident, revealing that Oad|OHad formation rate is faster than that for the removal of OHad to H2O under such conditions. At relatively lower rotation speed and faster scan rate, the cathodic current during ORR in the negative-going scan can be larger than that in the positive-going scan with a current peak at ca. 0.8 V, which is attributed to the superimposition of ORR current increase due to change of O2 concentration near the surface and the additional reduction of Oad|OHad formed from decomposed O2 at higher potentials. Keywords: O2 concentration, Oxygen reduction reaction, Rotating ring-disk electrode, Electrocatalysis, Fuel cell

Cyanide adsorption at the Pt film electrode in 0.1 M HClO4 is examined by electrochemical in situ infrared spectroscopy under attenuated total reflection configuration. N-bound Pt–NC with —N≡C stretching frequency from 2060 to 2135 cm–1, C-bound Pt–CN with —C≡N stretching frequency between 2140 and 2160 cm–1, and a trans-(HN═CH) adsorbate with C═N stretching frequency at 1639 cm–1 are identified; the latter only adsorbs at 0.05 V. The evolution of the spectral features reveal that the initial adsorption state of cyanide is in the form of Pt–NCHad, and then it fast splits into Pt–NC; furthermore, Pt—N≡C will slowly reorient to Pt—C≡N at longer adsorption time. The orientation of cyanide adsorbate at the Pt electrode surface is further confirmed by (i) the fact that the Stark slope for the —N≡C band is ca. 3 times larger than that for —C≡N and (ii) the spectral behavior of coadsorption of CO onto the presaturated cyanide adlayer: for Pt—N≡C, coadsorbed CO causes a blue shift in C≡N stretching frequency with...

Thin film rotating disk electrode (TFRDE) method is commonly used for studying the kinetics of gases reactants at electrodes composed of metal nanoparticles, whose solubility in the aqueous solutions are rather low (

The temperature dependence of hydrogen evolution reaction (HER) at a quasi-single crystalline gold electrode in both 0.1 mol/L HClO4 and 0.1 mol/L KOH solutions was investigated by cyclic voltammetry. HER current displays a clear increase with reaction overpotential (η) and temperature from 278–333 K. In 0.1 mol/L HClO4 the Tafel slopes are found to increases slightly with temperature from 118 mV/dec to 146 mV/dec, while in 0.1 mol/L KOH it is ca. 153±15 mV/dec without clear temperature-dependent trend. The apparent activation energy (Ea) for HER at equilibrium potential is ca. 48 and 34 kJ/mol in 0.1 mol/L HClO4 and 0.1 mol/L KOH, respectively. In acid solution, Ea decreases with increase in η, from Ea=37 kJ/mol (η=0.2 V) to 30 kJ/mol (η=0.35 V). In contrast, in 0.1 mol/L KOH, Ea does not show obvious change with η. The pre-exponential factor (A) in 0.1 mol/L HClO4 is ca. 1 order higher than that in 0.1 mol/L KOH. Toward more negative potential, in 0.1 mol/L HClO4 A changes little with potential, while in 0.1 mol/L KOH it displays a monotonic increase with η. The change trends of the potential-dependent kinetic parameters for HER at Au electrode in 0.1 mol/L HClO4 and that in 0.1 mol/L KOH are discussed.

The redox reaction of hydrogen peroxide (O2 + 2H+ + 2e ⇄ H2O2) at an Au(100) electrode/0.1 M HClO4 interface and the kinetic H–D isotope effect for O2 reduction have been investigated. It was found that i) the kinetics for electrochemical oxidation of H2O2 to O2 are very fast, occurring at a potential very close to its equilibrium potential (EO2/H2O2eq); ii) the kinetics for O2 reduction to H2O2 are much slower than those for H2O2 oxidation, with a H–D kinetic isotope effect of above two; and iii) the onset overpotential of H2O2 + 2H+ + 2e → 2H2O is ca. 1.4 V. Mechanistic insight and the origin for the high overpotential at the onset for O2 reduction at Au(100) are discussed. Keywords: Hydrogen peroxide oxidation, Hydrogen peroxide reduction, Oxygen reduction, Au(100) electrode, Overpotential, Kinetics

Cionus latefasciatus Voss (Coleoptera: Curculionidae) is one of the most important insect pests on Scrophularia ningpoensis Hemsl. (Scrophulariales: Scrophuhrhceae), which is a well-known traditional Chinese medicine plant in southeast China. The biological characteristics and effects of temperature on the growth and development of C. latefasciatus were studied in nature, in the greenhouse, and in the laboratory. In the area studied, 9-12 generations of this weevil occurred per year depending on climatic conditions. The overwintered adults migrated to the plant-seeding fields in the earlier days of March, and adults of the last generation began to overwinter in early October. Female adults lived for 50-75 d and male adults for 50-65 d at 28 degrees C. Adults fed on leaves, buds, tender stems, and flower stalks during the entire developmental phase of the plant. Female adults began to lay eggs 2-4 d after emergence and laid an average of 330-390 eggs per female at 28 degrees C. The eggs were usually laid on the surface of the leaves or into the leaves. The larvae have four instars judging from the width of the cephalic capsule of the larvae. The larvae fed on leaves and buds of the plant. Under constant temperatures (17, 20, 25, 28, and 30 degrees C) and fixed humidity (75%), the development periods from egg to adult emergence were 36.91, 29.25, 19.11, 17.26, and 15.36 d, respectively, and 346.31 degree-days, in total, above a lower threshold of 7.7 degrees C was required; the survival rates from egg to adult emergence were 49.1, 62.5, 72.0, 78.7, and 50.0%, respectively. Laboratory experiments showed that the optimum temperature for the development from egg to adult emergence was 28 degrees C.

Cionus latefasciatus Voss (Coleoptera: Curculionidae) is one of the most important insect pests on Scrophularia ningpoensis Hemsl. (Scrophulariales: Scrophuhrhceae), which is a well-known traditional Chinese medicine plant in southeast China. The biological characteristics and effects of temperature on the growth and development of C. latefasciatus were studied in nature, in the greenhouse, and in the laboratory. In the area studied, 9-12 generations of this weevil occurred per year depending on climatic conditions. The overwintered adults migrated to the plant-seeding fields in the earlier days of March, and adults of the last generation began to overwinter in early October. Female adults lived for 50-75 d and male adults for 50-65 d at 28 degrees C. Adults fed on leaves, buds, tender stems, and flower stalks during the entire developmental phase of the plant. Female adults began to lay eggs 2-4 d after emergence and laid an average of 330-390 eggs per female at 28 degrees C. The eggs were usually laid on the surface of the leaves or into the leaves. The larvae have four instars judging from the width of the cephalic capsule of the larvae. The larvae fed on leaves and buds of the plant. Under constant temperatures (17, 20, 25, 28, and 30 degrees C) and fixed humidity (75%), the development periods from egg to adult emergence were 36.91, 29.25, 19.11, 17.26, and 15.36 d, respectively, and 346.31 degree-days, in total, above a lower threshold of 7.7 degrees C was required; the survival rates from egg to adult emergence were 49.1, 62.5, 72.0, 78.7, and 50.0%, respectively. Laboratory experiments showed that the optimum temperature for the development from egg to adult emergence was 28 degrees C.

AIM: To prepare chitosan-polyaspartic acid-5-fluorouracil (CTS-Pasp-5Fu) nanoparticles and investigate its anti-carcinoma effect and toxicity. METHODS: CTS-Pasp-5Fu nanoparticles were synthesized by ionic gelatification. Male BABL/c nude mice were injected with SGC-7901 gastric carcinoma cell line mass to establish a human gastric carcinoma model. They were randomly allocated into 4 groups: CTS-Pasp-5Fu (containing 5-Fu 1.25 mg/kg), 5-Fu (1.25 mg/kg), CTS-Pasp and normal saline groups. Tumor weight was measured and assay of colony forming unit-granulocyte and macrophage (CFU-GM) was performed. The structural change of cells and tissues was observed and the Bax and Bcl-2 genes were detected. RESULTS: Compared with normal saline, the inhibition rates of tumor growth for the CTS-Pasp, 5-Fu and CTS-Pasp-5Fu groups were 5.58%, 58.69% and 70.82%, respectively. The tumor inhibition rates for the CTS-Pasp, 5-Fu and CTS-Pasp-5Fu groups were 5.09%, 65.3% and 72.79%, respectively. There was a significant decrease in the number of CFU-GM formation and increase of total bilirubin, and alanine aminotransferase in the 5-Fu group, but no change in those of the other three groups. There was no change in white blood cell count and creatinine among the four groups. Pathological section of liver and nephridial tissues showed that the damage in the 5-Fu group was more severe than that in the CTS-Pasp-5Fu group. 5-Fu and CTS-Pasp-5Fu groups could both down-regulate the Bcl-2 expression and up-regulate the Bax expression to different extent, and the accommodate effect of CTS-Pasp-5Fu was more obvious than 5-Fu. CONCLUSION: The tumor inhibition rate of CTS-Pasp-5Fu nanoparticles is much higher than that of 5-Fu alone.

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