Carbon-supported PdNi catalysts for the ethanol oxidation reaction in alkaline direct ethanol fuel cells are successfully synthesized by the simultaneous reduction method using NaBH
4 as reductant. ...X-ray diffraction characterization confirms the formation of the face-centered cubic crystalline Pd and Ni(OH)
2 on the carbon powder for the PdNi/C catalysts. Transmission electron microscopy images show that the metal particles are well-dispersed on the carbon powder, while energy-dispersive X-ray spectrometer results indicate the uniform distribution of Ni around Pd. X-ray photoelectron spectroscopy analyses reveal the chemical states of Ni, including metallic Ni, NiO, Ni(OH)
2 and NiOOH. Cyclic voltammetry and chronopotentiometry tests demonstrate that the Pd
2Ni
3/C catalyst exhibits higher activity and stability for the ethanol oxidation reaction in an alkaline medium than does the Pd/C catalyst. Fuel cell performance tests show that the application of Pd
2Ni
3/C as the anode catalyst of an alkaline direct ethanol fuel cell with an anion-exchange membrane can yield a maximum power density of 90
mW
cm
−2 at 60
°C.
Summary Objective Disruptions of extracellular matrix (ECM) homeostasis are key events in the pathogenesis of osteoarthritis (OA). MicroRNA-140 (miRNA-140) is expressed specifically in cartilage and ...regulates ECM-degrading enzymes. Our objective in this study was to determine if intra-articular injection of miRNA-140 can attenuate OA progression in rats. Design miRNA-140 levels in human normal and OA cartilage derived chondrocytes and synovial fluid were assessed by polymerase chain reaction (PCR). After primary human chondrocytes were transfected with miRNA-140 mimic or inhibitor, PCR and western blotting were performed to quantify Collagen II, MMP-13, and ADAMTS-5 expression. An OA model was induced surgically in rats, and subsequently treated with one single intra-articular injection of miRNA-140 agomir. At 4, 8, and 12 weeks after surgery, OA progression were evaluated macroscopically, histologically, and immunohistochemically in these rats. Results miRNA-140 levels were significantly reduced in human OA cartilage derived chondrocytes and synovial fluid compared with normal chondrocytes and synovial fluid. Overexpressing miRNA-140 in primary human chondrocytes promoted Collagen II expression and inhibited MMP-13 and ADAMTS-5 expression. miRNA-140 levels in rat cartilage were significantly higher in the miRNA-140 agomir group than in the control group. Moreover, behavioural scores, chondrocyte numbers, cartilage thickness and Collagen II expression levels in cartilage were significantly higher, while pathological scores and MMP-13 and ADAMTS-5 expression levels were significantly lower in the miRNA-140 agomir group than in the control group. Conclusion Intra-articular injection of miRNA-140 can alleviate OA progression by modulating ECM homeostasis in rats, and may have potential as a new therapy for OA.
With the aim of gathering temporal trends on bacterial epidemiology and resistance from multiple laboratories in China, the CHINET surveillance system was organized in 2005. Antimicrobial ...susceptibility testing was carried out according to a unified protocol using the Kirby-Bauer method or automated systems. Results were analyzed according to Clinical and Laboratory Standards Institute (CLSI) 2014 definitions. Between 2005 and 2014, the number of bacterial isolates ranged between 22 774 and 84 572 annually. Rates of extended-spectrum β-lactamase production among Escherichia coli isolates were stable, between 51.7 and 55.8%. Resistance of E. coli and Klebsiella pneumoniae to amikacin, ciprofloxacin, piperacillin/tazobactam and cefoperazone/sulbactam decreased with time. Carbapenem resistance among K. pneumoniae isolates increased from 2.4 to 13.4%. Resistance of Pseudomonas aeruginosa strains against all of antimicrobial agents tested including imipenem and meropenem decreased with time. On the contrary, resistance of Acinetobacter baumannii strains to carbapenems increased from 31 to 66.7%. A marked decrease of methicillin resistance from 69% in 2005 to 44.6% in 2014 was observed for Staphylococcus aureus. Carbapenem resistance rates in K. pneumoniae and A. baumannii in China are high. Our results indicate the importance of bacterial surveillance studies.
A theoretical and experimental perspective on the role of titanium impurities in hematite (α-Fe
2
O
3
) nanostructured photoelectrodes for solar fuel synthesis devices is provided. Titanium ...incorporation is a known correlate to efficiency enhancement in α-Fe
2
O
3
photoanodes for solar water oxidation; here the relevant literature and the latest advances are presented and various proposed mechanisms for enhancement are contrasted. Available experimental evidence suggests that Ti incorporation increases net electron carrier concentrations in electrodes, most likely to the extent that (synthesis-dependent) charge compensating cation vacancies are not present. However, electron conductivity increases alone cannot quantitatively account for the large associated photoelectrochemical performance enhancements. The magnitudes of the effects of Ti incorporation on electronic and magnetic properties appear to be highly synthesis-dependent, which has made difficult the development of consistent and general mechanisms explaining experimental and theoretical observations. In this context, we consider how the electronic structure correlates with Ti impurity incorporation in α-Fe
2
O
3
from the perspective of synchrotron-based soft X-ray absorption spectroscopy measurements. Measurements are performed on sets of electrodes fabricated by five relevant and unrelated chemical and physical techniques. The effects of titanium impurities are reflected in the electronic structure through several universally observed spectral characteristics, irrespective of the synthesis techniques. Absorption spectra at the oxygen K-edge show that Ti incorporation is associated with new oxygen 2p-hybridized states, overlapping with and distorting the known unoccupied Fe 3d-O 2p band of α-Fe
2
O
3
. This is an indication of mixing of Ti s and d states in the conduction band of α-Fe
2
O
3
. A comparison of spectra obtained with electron and photon detection shows that the effects of Ti incorporation on the conduction band are more pronounced in the near-surface region. Titanium L
2,3
-edge absorption spectra show that titanium is incorporated into α-Fe
2
O
3
as Ti
4+
by all fabrication methods, with no long-range titania order detected. Iron L
2,3
-edge absorption spectra indicate that Ti incorporation is not associated with the formation of any significant concentrations of Fe
2+
, an observation common to many prior studies on this material system.
A thorough literature review and the investigation by soft X-ray absorption spectroscopy at synchrotron facilities of Ti-Hematite photoelectrodes are provided.
High-temperature copper oxide superconductors consist of stacked CuO
planes, with electronic band structures and magnetic excitations that are primarily two-dimensional
, but with superconducting ...coherence that is three-dimensional. This dichotomy highlights the importance of out-of-plane charge dynamics, which has been found to be incoherent in the normal state
within the limited range of momenta accessible by optics. Here we use resonant inelastic X-ray scattering to explore the charge dynamics across all three dimensions of the Brillouin zone. Polarization analysis of recently discovered collective excitations (modes) in electron-doped copper oxides
reveals their charge origin, that is, without mixing with magnetic components
. The excitations disperse along both the in-plane and out-of-plane directions, revealing its three-dimensional nature. The periodicity of the out-of-plane dispersion corresponds to the distance between neighbouring CuO
planes rather than to the crystallographic c-axis lattice constant, suggesting that the interplane Coulomb interaction is responsible for the coherent out-of-plane charge dynamics. The observed properties are hallmarks of the long-sought 'acoustic plasmon', which is a branch of distinct charge collective modes predicted for layered systems
and argued to play a substantial part in mediating high-temperature superconductivity
.
Cancer patients are regarded as a highly vulnerable group in the current Coronavirus Disease 2019 (COVID-19) pandemic. To date, the clinical characteristics of COVID-19-infected cancer patients ...remain largely unknown.
In this retrospective cohort study, we included cancer patients with laboratory-confirmed COVID-19 from three designated hospitals in Wuhan, China. Clinical data were collected from medical records from 13 January 2020 to 26 February 2020. Univariate and multivariate analyses were carried out to assess the risk factors associated with severe events defined as a condition requiring admission to an intensive care unit, the use of mechanical ventilation, or death.
A total of 28 COVID-19-infected cancer patients were included; 17 (60.7%) patients were male. Median (interquartile range) age was 65.0 (56.0–70.0) years. Lung cancer was the most frequent cancer type (n = 7; 25.0%). Eight (28.6%) patients were suspected to have hospital-associated transmission. The following clinical features were shown in our cohort: fever (n = 23, 82.1%), dry cough (n = 22, 81%), and dyspnoea (n = 14, 50.0%), along with lymphopaenia (n = 23, 82.1%), high level of high-sensitivity C-reactive protein (n = 23, 82.1%), anaemia (n = 21, 75.0%), and hypoproteinaemia (n = 25, 89.3%). The common chest computed tomography (CT) findings were ground-glass opacity (n = 21, 75.0%) and patchy consolidation (n = 13, 46.3%). A total of 15 (53.6%) patients had severe events and the mortality rate was 28.6%. If the last antitumour treatment was within 14 days, it significantly increased the risk of developing severe events hazard ratio (HR) = 4.079, 95% confidence interval (CI) 1.086–15.322, P = 0.037. Furthermore, patchy consolidation on CT on admission was associated with a higher risk of developing severe events (HR = 5.438, 95% CI 1.498–19.748, P = 0.010).
Cancer patients show deteriorating conditions and poor outcomes from the COVID-19 infection. It is recommended that cancer patients receiving antitumour treatments should have vigorous screening for COVID-19 infection and should avoid treatments causing immunosuppression or have their dosages decreased in case of COVID-19 coinfection.
•We retrospectively studied clinical features of 28 severe Coronavirus Disease 2019 (COVID-19)-infected cancer patients from three hospitals in Wuhan, China.•We analysed risk factors associated with occurrence of admission to an intensive care unit, usage of mechanical ventilation, or death.•COVID-19-infected cancer patients presented poor outcomes with high occurrence of clinically severe event and mortality.•Antitumour treatment within 14 days of COVID-19 diagnosis increased the risk of developing severe events.
We report the first results of a light weakly interacting massive particles (WIMPs) search from the CDEX-10 experiment with a 10 kg germanium detector array immersed in liquid nitrogen at the China ...Jinping Underground Laboratory with a physics data size of 102.8 kg day. At an analysis threshold of 160 eVee, improved limits of 8×10^{-42} and 3×10^{-36} cm^{2} at a 90% confidence level on spin-independent and spin-dependent WIMP-nucleon cross sections, respectively, at a WIMP mass (m_{χ}) of 5 GeV/c^{2} are achieved. The lower reach of m_{χ} is extended to 2 GeV/c^{2}.
Motivated by the idea that a monometal catalyst can become more stabilized with the incorporation of gold due to its unique electron-withdrawing effect to neighboring primary metal atoms, in this ...work we prepare Pd–Au alloy electrocatalysts for the ethanol oxidation reaction in an alkaline medium with the dimethylformamide co-reduction method under an ultrasonic process. The atomic ratio of Pd to Au is varied from 7:1 to 3:1 and 1:1 on the basis of a crystal cell of the face-centered cubic. Electrochemical characterizations indicate that in terms of the peak current density, the prepared catalyst samples are in sequence of Pd/C
>
Pd
3Au/C
>
Pd
7Au/C
>
PdAu/C, but the stability tests demonstrate that the catalyst samples are sequenced in PdAu/C
>
Pd
3Au/C
>
Pd
7Au/C
>
Pd/C. On the compromise between the activity and stability, it turns out that the Pd
3Au/C can exhibit an enhanced catalytic stability while maintain the comparable catalytic activity for the ethanol oxidation reaction as compared with the monometallic Pd/C catalyst.
We characterize one transcription factor of DRE-binding proteins (TaDREB1) that was isolated from a drought-induced cDNA library of wheat (Triticum aestivum L.). TaDREB1 contains one conserved ...EREBP/AP2 domain, and shows similarity with Arabidopsis thaliana DREB family members in both overall amino-acid sequences and the secondary structure arrangement within the DNA-binding motifs. In yeast one-hybrid system, TaDREB1, can specially activate the genes fused with the promoter containing three tandemly repeated copies of the wild-type DRE sequence: TACCGACAT. In different wheat cultivars, the Ta DREB1 gene is induced by low temperature, salinity and drought; and the expression of Wcs120 that contains DRE motifs in its promoter is closely related to the expression of TaDREB1. These results suggest that TaDREB1 functions as a DRE-binding transcription factor in wheat. We also observed the dwarf phenotype in transgenic rice (T0) overexpressing TaDREB1.
We present results on light weakly interacting massive particle (WIMP) searches with annual modulation (AM) analysis on data from a 1-kg mass p-type point-contact germanium detector of the CDEX-1B ...experiment at the China Jinping Underground Laboratory. Datasets with a total live time of 3.2 yr within a 4.2-yr span are analyzed with analysis threshold of 250 eVee. Limits on WIMP-nucleus (χ-N) spin-independent cross sections as function of WIMP mass (m_{χ}) at 90% confidence level (C.L.) are derived using the dark matter halo model. Within the context of the standard halo model, the 90% C.L. allowed regions implied by the DAMA/LIBRA and CoGeNT AM-based analysis are excluded at >99.99% and 98% C.L., respectively. These results correspond to the best sensitivity at m_{χ}<6 GeV/c^{2} among WIMP AM measurements to date.
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