Showing papers by "Jun Lu published in 2014"
TL;DR: This work reports on the fabrication of ∼1 × 1 cm2 Ti3C2 films by selective etching of Al, from sputter-deposited epitaxial Ti3AlC 2 films, in aqueous HF or NH4HF2, and opens the door for the use of MXenes in electronic, photonic, and sensing applications.
Abstract: Since the discovery of graphene, the quest for two-dimensional (2D) materials has intensified greatly. Recently, a new family of 2D transition metal carbides and carbonitrides (MXenes) was discovered that is both conducting and hydrophilic, an uncommon combination. To date MXenes have been produced as powders, flakes, and colloidal solutions. Herein, we report on the fabrication of ∼1 × 1 cm2 Ti3C2 films by selective etching of Al, from sputter-deposited epitaxial Ti3AlC2 films, in aqueous HF or NH4HF2. Films that were about 19 nm thick, etched with NH4HF2, transmit ∼90% of the light in the visible-to-infrared range and exhibit metallic conductivity down to ∼100 K. Below 100 K, the films’ resistivity increases with decreasing temperature and they exhibit negative magnetoresistance—both observations consistent with a weak localization phenomenon characteristic of many 2D defective solids. This advance opens the door for the use of MXenes in electronic, photonic, and sensing applications.
1,015 citations
TL;DR: The feasibility of tungsten disulfide nanotubes/graphene sandwich-type architecture as anode for lithium-ion batteries for the first time is demonstrated and the relatively high density of this hybrid is beneficial for high capacity per unit volume.
Abstract: Transition metal dichalcogenides (TMD), analogue of graphene, could form various dimensionalities. Similar to carbon, one-dimensional (1D) nanotube of TMD materials has wide application in hydrogen storage, Li-ion batteries, and supercapacitors due to their unique structure and properties. Here we demonstrate the feasibility of tungsten disulfide nanotubes (WS2-NTs)/graphene (GS) sandwich-type architecture as anode for lithium-ion batteries for the first time. The graphene-based hierarchical architecture plays vital roles in achieving fast electron/ion transfer, thus leading to good electrochemical performance. When evaluated as anode, WS2–NTs/GS hybrid could maintain a capacity of 318.6 mA/g over 500 cycles at a current density of 1A/g. Besides, the hybrid anode does not require any additional polymetric binder, conductive additives, or a separate metal current-collector. The relatively high density of this hybrid is beneficial for high capacity per unit volume. Those characteristics make it a potential ...
255 citations
TL;DR: The surface-doped lithium manganate demonstrates enhanced electrochemical performance and provides encouraging evidence that surface doping could be a promising alternative to improve the cycling performance of lithium-ion batteries.
Abstract: The capacity fade of lithium manganate-based cells is associated with the dissolution of Mn from cathode/electrolyte interface due to the disproportionation reaction of Mn(III), and the subsequent deposition of Mn(II) on the anode. Suppressing the dissolution of Mn from the cathode is critical to reducing capacity fade of LiMn2O4-based cells. Here we report a nanoscale surface-doping approach that minimizes Mn dissolution from lithium manganate. This approach exploits advantages of both bulk doping and surface-coating methods by stabilizing surface crystal structure of lithium manganate through cationic doping while maintaining bulk lithium manganate structure, and protecting bulk lithium manganate from electrolyte corrosion while maintaining ion and charge transport channels on the surface through the electrochemically active doping layer. Consequently, the surface-doped lithium manganate demonstrates enhanced electrochemical performance. This study provides encouraging evidence that surface doping could be a promising alternative to improve the cycling performance of lithium-ion batteries.
246 citations
TL;DR: There is a circuit substrate through which GABAergic PZ neurons can potently trigger SWS and modulate the cortical EEG, regardless of the time of day, and this circuit uniquely and potently initiatedSWS and EEG SWA.
Abstract: Work in animals and humans has suggested the existence of a slow wave sleep (SWS)-promoting/electroencephalogram (EEG)-synchronizing center in the mammalian lower brainstem. Although sleep-active GABAergic neurons in the medullary parafacial zone (PZ) are needed for normal SWS, it remains unclear whether these neurons can initiate and maintain SWS or EEG slow-wave activity (SWA) in behaving mice. We used genetically targeted activation and optogenetically based mapping to examine the downstream circuitry engaged by SWS-promoting PZ neurons, and we found that this circuit uniquely and potently initiated SWS and EEG SWA, regardless of the time of day. PZ neurons monosynaptically innervated and released synaptic GABA onto parabrachial neurons, which in turn projected to and released synaptic glutamate onto cortically projecting neurons of the magnocellular basal forebrain; thus, there is a circuit substrate through which GABAergic PZ neurons can potently trigger SWS and modulate the cortical EEG.
245 citations
TL;DR: In this paper, the application of ultrasonic-assisted technology to the leaching of cobalt and lithium from the cathode active materials of spent LIBs was reported, and three acids were tested for the leach process: two inorganic acids (H2SO4 and HCl) and one organic acid (C6H8O7·H2O).
218 citations
TL;DR: High-power, long-life carbon-coated TiO2 microsphere electrodes were synthesized by a hydrothermal method for sodium ion batteries, and the electrochemical properties were evaluated as a function of carbon content.
Abstract: High-power, long-life carbon-coated TiO2 microsphere electrodes were synthesized by a hydrothermal method for sodium ion batteries, and the electrochemical properties were evaluated as a function of carbon content. The carbon coating, introduced by sucrose addition, had an effect of suppressing the growth of the TiO2 primary crystallites during calcination. The carbon coated TiO2 (sucrose 20 wt % coated) electrode exhibited excellent cycle retention during 50 cycles (100%) and superior rate capability up to a 30 C rate at room temperature. This cell delivered a high discharge capacity of 155 mAh g(composite)(-1) at 0.1 C, 149 mAh g(composite)(-1) at 1 C, and 82.7 mAh g(composite)(-1) at a 10 C rate, respectively.
211 citations
TL;DR: The authors showed that a pulse of CCAAT/enhancer binding protein-α (C/EBPα) followed by overexpression of the Yamanaka 'OSKM' reprogramming factors leads to fast and very efficient B-cell precursors to induced pluripotent stem (iPS) cells.
Abstract: A pulse of C/EBPα followed by overexpression of the transcription factors Oct4, Sox2, Klf4 and Myc leads to fast and very efficient reprogramming of B cell precursors to induced pluripotent stem cells; C/EBPα facilitates transient chromatin accessibility and accelerates expression of pluripotency genes through a mechanism that involves activation of the Tet2 enzyme. A new study by Thomas Graf and colleagues describes how a pulse of C/EBPα (the transcription factor CCAAT/enhancer binding protein-α) followed by overexpression of the Yamanaka 'OSKM' reprogramming factors leads to fast and very efficient reprogramming of B-cell precursors to induced pluripotent stem (iPS) cells. The authors found that C/EBPα facilitates chromatin accessibility and accelerates expression of pluripotency genes through a mechanism that involves activation of the Tet2 enzyme. This demonstration of highly efficient and fast reprogramming of B cells into iPS cells provides a model for the study of the reprogramming process and may also have clinical relevance. CCAAT/enhancer binding protein-α (C/EBPα) induces transdifferentiation of B cells into macrophages at high efficiencies and enhances reprogramming into induced pluripotent stem (iPS) cells when co-expressed with the transcription factors Oct4 (Pou5f1), Sox2, Klf4 and Myc (hereafter called OSKM)1,2. However, how C/EBPα accomplishes these effects is unclear. Here we find that in mouse primary B cells transient C/EBPα expression followed by OSKM activation induces a 100-fold increase in iPS cell reprogramming efficiency, involving 95% of the population. During this conversion, pluripotency and epithelial–mesenchymal transition genes become markedly upregulated, and 60% of the cells express Oct4 within 2 days. C/EBPα acts as a ‘path-breaker’ as it transiently makes the chromatin of pluripotency genes more accessible to DNase I. C/EBPα also induces the expression of the dioxygenase Tet2 and promotes its translocation to the nucleus where it binds to regulatory regions of pluripotency genes that become demethylated after OSKM induction. In line with these findings, overexpression of Tet2 enhances OSKM-induced B-cell reprogramming. Because the enzyme is also required for efficient C/EBPα-induced immune cell conversion3, our data indicate that Tet2 provides a mechanistic link between iPS cell reprogramming and B-cell transdifferentiation. The rapid iPS reprogramming approach described here should help to fully elucidate the process and has potential clinical applications.
187 citations
183 citations
TL;DR: The deposition of subnanometre silver clusters of exact size and number of atoms on passivated carbon to study the discharge process in lithium-oxygen cells reveal dramatically different morphologies of the electrochemically grown lithium peroxide dependent on the size of the clusters.
Abstract: Lithium-oxygen batteries have the potential needed for long-range electric vehicles, but the charge and discharge chemistries are complex and not well understood. The active sites on cathode surfaces and their role in electrochemical reactions in aprotic lithium-oxygen cells are difficult to ascertain because the exact nature of the sites is unknown. Here we report the deposition of subnanometre silver clusters of exact size and number of atoms on passivated carbon to study the discharge process in lithium-oxygen cells. The results reveal dramatically different morphologies of the electrochemically grown lithium peroxide dependent on the size of the clusters. This dependence is found to be due to the influence of the cluster size on the formation mechanism, which also affects the charge process. The results of this study suggest that precise control of subnanometre surface structure on cathodes can be used as a means to improve the performance of lithium-oxygen cells.
175 citations
TL;DR: The data demonstrate that the stochastic nature of reprogramming can be overcome in a privileged somatic cell state and suggest that cell-cycle acceleration toward a critical threshold is an important bottleneck for reprograming.
171 citations
TL;DR: Investigation of LiODFB as an organic electrolyte additive to improve the cycling performance of Li-S batteries showed that it promotes the formation of a LiF-rich passivation layer on the lithium metal surface, which not only blocks the polysulfide shuttle, but also stabilizes the lithium surface.
Abstract: Lithium oxalyldifluoroborate (LiODFB) has been investigated as an organic electrolyte additive to improve the cycling performance of Li–S batteries. Cell test results demonstrate that an appropriate amount of LiODFB added into the electrolyte leads to a high Coulombic efficiency. Analyses by energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and the density functional theory showed that LiODFB promotes the formation of a LiF-rich passivation layer on the lithium metal surface, which not only blocks the polysulfide shuttle, but also stabilizes the lithium surface.
TL;DR: In this article, the genomes of four different mudskipper species were sequenced and genetic changes that may have had an evolutionary role in the water-to-land transition of vertebrates were highlighted.
Abstract: Mudskippers are amphibious fishes that have adapted to live on mudflats. Here, the authors sequence the genomes of four different mudskipper species and highlight genetic changes that may have had an evolutionary role in the water-to-land transition of vertebrates.
TL;DR: The piperidine analog 3 (MK-7655) effectively restored imipenem's activity against imipanem-resistant Pseudomonas and Klebsiella strains at clinically achievable concentrations.
TL;DR: In this article, the design and development of a 32 T, 32 mm cold bore superconducting magnet with high field REBCO inner coils are underway at the NHMFL.
Abstract: The design and development of a 32 T, 32 mm cold bore superconducting magnet with high field REBCO inner coils are underway at the NHMFL. The two nested REBCO coils that form the high field section are dry wound, with uninsulated conductor and insulated stainless steel cowind reinforcement. Active quench protection uses distributed protection heaters. As part of the development activity, prototype coils of the two REBCO coils with full scale radial dimensions and final design features, but with reduced axial length are being constructed. The first of these prototype coils was tested in a 15 T resistive background field magnet. The coil has inner and outer winding diameters of 40 mm and 140 mm, respectively, and consists of six double pancakes with a total conductor length of roughly 900 m. The construction of this prototype coil is described, including the protection heaters. Coil test results are reported including coil critical current, coil ramping characteristics, thermal stability, joint, and terminal resistance with field cycling. The corresponding operating stress in the windings is calculated. Importantly, the performance characteristics of the protection heaters will be measured including activation time.
TL;DR: In this paper, the authors review results on the growth of metastable Ti1−xAlxN alloy films by hybrid high-power pulsed and dc magnetron co-sputtering (HIPIMS/DCMS) using the time domain to apply substrate bias either in synchronous with the entire HIPIMS pulse or just the metal-rich portion of the pulse in mixed Ar/N2 discharges.
Abstract: We review results on the growth of metastable Ti1−xAlxN alloy films by hybrid high-power pulsed and dc magnetron co-sputtering (HIPIMS/DCMS) using the time domain to apply substrate bias either in synchronous with the entire HIPIMS pulse or just the metal-rich portion of the pulse in mixed Ar/N2 discharges. Depending upon which elemental target, Ti or Al, is powered by HIPIMS, distinctly different film-growth kinetic pathways are observed due to charge and mass differences in the metal-ion fluxes incident at the growth surface. Al+ ion irradiation during Al–HIPIMS/Ti–DCMS at 500 °C, with a negative substrate bias Vs = 60 V synchronized to the HIPIMS pulse (thus suppressing Ar+ ion irradiation due to DCMS), leads to single-phase NaCl-structure Ti1−xAlxN films (x ≤ 0.60) with high hardness (> 30 GPa with x > 0.55) and low stress (0.2–0.8 GPa compressive). Ar+ ion bombardment can be further suppressed in favor of predominantly Al+ ion irradiation by synchronizing the substrate bias to only the metal-ion-rich portion of the Al–HIPIMS pulse. In distinct contrast, Ti–HIPIMS/Al–DCMS Ti1 − xAlxN layers grown with Ti+/Ti2 + metal ion irradiation and the same HIPIMS-synchronized Vs value, are two-phase mixtures, NaCl-structure Ti1−xAlxN plus wurtzite AlN, exhibiting low hardness (≃ 18 GPa) with high compressive stresses, up to − 3.5 GPa. In both cases, film properties are controlled by the average metal-ion momentum per deposited atom transferred to the film surface. During Ti–HIPIMS, the growing film is subjected to an intense flux of doubly-ionized Ti2+, while Al2+ irradiation is insignificant during Al–HIPIMS. This asymmetry is decisive since the critical limit for precipitation of w-AlN, 135 [eV-amu]1/2, is easily exceeded during Ti–HIPIMS, even with no intentional bias. The high Ti2 + ion flux is primarily due to the second ionization potential (IP2) of Ti being lower than the first IP (IP1) of Ar. New results involving the HIPIMS growth of metastable Ti1−xAlxN alloy films from segmented TiAl targets are consistent with the above conclusions.
TL;DR: The results can be a guide for future studies and control of the sulfur species and meanwhile a baseline for approaching the theoretical capacity of the Li-S battery.
Abstract: Understanding and controlling the sulfur reduction species (Li2Sx, 1 ≤ x ≤ 8) under realistic battery conditions are essential for the development of advanced practical Li–S cells that can reach their full theoretical capacity. However, it has been a great challenge to probe the sulfur reduction intermediates and products because of the lack of methods. This work employed various ex situ and in situ methods to study the mechanism of the Li–S redox reactions and the properties of Li2Sx and Li2S. Synchrotron high-energy X-ray diffraction analysis used to characterize dry powder deposits from lithium polysulfide solution suggests that the new crystallite phase may be lithium polysulfides. The formation of Li2S crystallites with a polyhedral structure was observed in cells with both the conventional (LiTFSI) electrolyte and polysulfide-based electrolyte. In addition, an in situ transmission electron microscopy experiment observed that the lithium diffusion to sulfur during discharge preferentially occurred at...
TL;DR: In this article, it was found that the ZnO shell formed by a reaction of Na2S with ZnNPs followed by the formation of ZnS nano-crystals by the reaction of N2S and ZnCl2 at a later stage of the growth.
Abstract: ZnO nanoparticles were synthesized by co-precipitation with no capping agent followed by covering with ZnS using a solution-based chemical method at low temperature By variation of the solution concentrations it was found that the fully-covering ZnS shell forms by a reaction of Na2S with ZnO NPs followed by the formation of ZnS nano-crystals by the reaction of Na2S with ZnCl2 The mechanism that led to full coverage of the ZnO core is proposed to be the addition of ZnCl2 at a later stage of the growth which guarantees a continuous supply of Zn ions to the core surface Moreover, the ZnS nanocrystals that uniformly cover the ZnO NPs show no epitaxial relationship between the ZnO core and ZnS shell The slow atomic mobility at the low reaction temperature is attributed to the non-epitaxial uniform ZnS shell growth The rough surface of the ZnO grains provides initial nucleation positions for the growth of the ZnS shell nano-crystals The low growth temperature also inhibits the abnormal growth of ZnS grains and results in the homogeneous coverage of ZnS nano-crystals on the ZnO core surface The as-synthesized ZnO@ZnS core–shell nanoparticles were used as a photocatalyst to decompose Rose Bengal dye at three different pH values ZnO@ZnS core–shell nanoparticles perform as a more active photocatalyst at a pH of 4, while pure ZnO nanoparticles are more efficient at a pH of 7
TL;DR: The crystal structure and chemical bonding of magnetron-sputtering deposited nickel carbide Ni₁-xCx thin films have been investigated and it is shown that the resistivity is not only governed by the amount of carbon, but increases by more than a factor of two when the samples transform from crystalline to amorphous.
Abstract: The crystal structure and chemical bonding of magnetron-sputtering deposited nickel carbide Ni1−xCx (0.05≤x≤0.62) thin films have been investigated by high-resolution x-ray diffraction, transmissio ...
TL;DR: In this article, a carbon-containing nickel carbide thin film was investigated using high-resolution X-ray diffraction, transmission electron microscopy, Xray photoelectron spectroscopy, Raman spectroscopic analysis, and soft Xray absorption spectra.
Abstract: The crystal structure and chemical bonding of magnetron-sputtering deposited nickel carbide Ni$_{1-x}$C$_{x}$ (0.05$\leq$x$\leq$0.62) thin films have been investigated by high-resolution X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and soft X-ray absorption spectroscopy. By using X-ray as well as electron diffraction, we found carbon-containing hcp-Ni (hcp-NiC$_{y}$ phase), instead of the expected rhombohedral-Ni$_{3}$C. At low carbon content (4.9 at\%) the thin film consists of hcp-NiC$_{y}$ nanocrystallites mixed with a smaller amount of fcc-NiC$_{x}$. The average grain size is about 10-20 nm. With the increase of carbon content to 16.3 at\%, the film contains single-phase hcp-NiC$_{y}$ nanocrystallites with expanded lattice parameters. With further increase of carbon content to 38 at\%, and 62 at\%, the films transform to X-ray amorphous materials with hcp-NiC$_{y}$ and fcc-NiC$_{x }$ nanodomain structures in an amorphous carbon-rich matrix. Raman spectra of carbon indicate dominant $sp^{2}$ hybridization, consistent with photoelectron spectra that show a decreasing amount of C-Ni phase with increasing carbon content. The Ni $3d$ - C $2p$ hybridization in the hexagonal structure gives rise to the salient double-peak structure in Ni $2p$ soft X-ray absorption spectra at 16.3 at\% that changes with carbon content. We also show that the resistivity is not only governed by the amount of carbon, but increases by more than a factor of two when the samples transform from crystalline to amorphous.
TL;DR: Li-rich layered oxide Li1.2Co0.13Ni0.54O2 has been successfully re-synthesized using the ascorbic acid leaching solution of spent lithium-ion batteries as the raw materials as discussed by the authors.
TL;DR: General applicability of the models was indicated by good performance in cross-species validations and major improvements over established algorithms in predictions of both seed and seedless sites.
Abstract: STarMir web server predicts microRNA (miRNA) binding sites on a target ribonucleic acid (RNA). STarMir is an implementation of logistic prediction models developed with miRNA binding data from crosslinking immunoprecipitation (CLIP) studies (Liu,C., Mallick, B., Long, D., Rennie, W.A., Wolenc, A., Carmack, C.S. and Ding, Y. (2013). CLIP-based prediction of mammalian microRNA binding sites. Nucleic Acids Res., 41(14), e138). In both intra-dataset and inter-dataset validations, the models showed major improvements over established algorithms in predictions of both seed and seedless sites. General applicability of the models was indicated by good performance in cross-species validations. The input data for STarMir is processed by the web server to perform prediction of miRNA binding sites, compute comprehensive sequence, thermodynamic and target structure features and a logistic probability as a measure of confidence for each predicted site. For each of seed and seedless sites and for all three regions of a mRNA (3' UTR, CDS and 5' UTR), STarMir output includes the computed binding site features, the logistic probability and a publication-quality diagram of the predicted miRNA:target hybrid. The prediction results are available through both an interactive viewer and downloadable text files. As an application module of the Sfold RNA package (http://sfold.wadsworth.org), STarMir is freely available to all at http://sfold.wadsworth.org/starmir.html.
TL;DR: In this paper, the aluminum-containing solid solution Mn+1AXn phases were synthesized using Rietveld analysis of powder X-ray diffraction patterns to calculate the lattice parameters and phase fractions.
Abstract: We synthesized the following previously unreported aluminum-containing solid solution Mn+1AXn phases: (Ti0.5, V0.5)3AlC2, (Nb0.5, V0.5)2AlC, (Nb0.5, V0.5)4AlC3 and (Nb0.8, Zr0.2)2AlC. Rietveld analysis of powder X-ray diffraction patterns was used to calculate the lattice parameters and phase fractions. Heating Ti, V, Al and C elemental powders—in the molar ratio of 1.5:1.5:1.3:2—to 1, 450°C for 2 h in flowing argon, resulted in a predominantly phase pure sample of (Ti0.5, V0.5)3AlC2. The other compositions were not as phase pure and further work on optimizing the processing parameters needs to be carried out if phase purity is desired.
TL;DR: This "dual-arm", U-shaped, multicontact binding mode of kibdelomycin is unique and distinctively different from binding modes of other known gyrase inhibitors (e.g., coumarins and quinolones), which explains its lack of cross-resistance and low frequency of resistance.
Abstract: Bacterial resistance to antibiotics continues to pose serious challenges as the discovery rate for new antibiotics fades. Kibdelomycin is one of the rare, novel, natural product antibiotics discovered recently that inhibits the bacterial DNA synthesis enzymes gyrase and topoisomerase IV. It is a broad-spectrum, Gram-positive antibiotic without cross-resistance to known gyrase inhibitors, including clinically effective quinolones. To understand its mechanism of action, binding mode, and lack of cross-resistance, we have co-crystallized kibdelomycin and novobiocin with the N-terminal domains of Staphylococcus aureus gyrase B (24 kDa) and topo IV (ParE, 24 and 43 kDa). Kibdelomycin shows a unique “dual-arm”, U-shaped binding mode in both crystal structures. The pyrrolamide moiety in the lower part of kibdelomycin penetrates deeply into the ATP-binding site pocket, whereas the isopropyl-tetramic acid and sugar moiety of the upper part thoroughly engage in polar interactions with a surface patch of the protein...
TL;DR: In this paper, a combination of experiments and density functional theory was used to demonstrate the first example of vacancy-induced toughening, in this case for epitaxial pseudobinary NaCl-structure substoichiometric V0.5Mo 0.5Nx alloys.
TL;DR: Novel bacterial topoisomerase inhibitors are described, which are a new class of gyrase and topo IV inhibitors and consist of three distinct structural moieties and led to discovery of potent broad-spectrum NBTIs with reduced off-target activity and improved physical properties.
Abstract: Bacterial resistance is eroding the clinical utility of existing antibiotics necessitating the discovery of new agents. Bacterial type II topoisomerase is a clinically validated, highly effective, and proven drug target. This target is amenable to inhibition by diverse classes of inhibitors with alternative and distinct binding sites to quinolone antibiotics, thus enabling the development of agents that lack cross-resistance to quinolones. Described here are novel bacterial topoisomerase inhibitors (NBTIs), which are a new class of gyrase and topo IV inhibitors and consist of three distinct structural moieties. The substitution of the linker moiety led to discovery of potent broad-spectrum NBTIs with reduced off-target activity (hERG IC50 > 18 μM) and improved physical properties. AM8191 is bactericidal and selectively inhibits DNA synthesis and Staphylococcus aureus gyrase (IC50 = 1.02 μM) and topo IV (IC50 = 10.4 μM). AM8191 showed parenteral and oral efficacy (ED50) at less than 2.5 mg/kg doses in a S....
TL;DR: The results show that functionally competent K+ channels are present in human atrial and ventricular TCs and their modulation may have significant implications in myocardial physiopathology.
Abstract: Telocytes (TCs) with exceptionally long cellular processes of telopodes have been described in human epicardium to act as structural supporting cells in the heart. We examined myocardial chamber-specific TCs identified in atrial and ventricular fibroblast culture using immunocytochemistry and studied their electrophysiological property by whole-cell patch clamp. Atrial and ventricular TCs with extended telopodes and alternating podoms and podomers that expressed CD34, c-Kit and PDGFR-β were identified. These cells expressed large conductance Ca2+-activated K+ current (BKCa) and inwardly rectifying K+ current (IKir), but not transient outward K+ current (Ito) and ATP-sensitive potassium current (KATP). The active channels were functionally competent with demonstrated modulatory response to H2S and transforming growth factor (TGF)-β1 whereby H2S significantly inhibited the stimulatory effect of TGF-β1 on current density of both BKCa and IKir. Furthermore, H2S attenuated TGF-β1-stimulated KCa1.1/Kv1.1 (encode BKCa) and Kir2.1 (encode IKir) expression in TCs. Our results show that functionally competent K+ channels are present in human atrial and ventricular TCs and their modulation may have significant implications in myocardial physiopathology.
TL;DR: New Zealand U. pinnatifida sporophyll had a high level of beneficial lipids and could potentially be further processed as a source of functional food lipids instead of being discarded as a waste product.
TL;DR: In this article, a hybrid deposition process consisting of reactive high-power pulsed and dc magnetron cosputtering (HIPIMS and DCMS) from Ti and Al targets is used to grow Ti 1− x Al x N alloys.
TL;DR: In this paper, solid solution alloys of magnesium were exploited as a way to destabilize magnesium hydride thermodynamically, and the equilibrium pressures were determined by pressure-composition-isothermal (PCI) measurements.
Abstract: Thermodynamic destabilization of magnesium hydride is a difficult task that has challenged researchers of metal hydrides for decades. In this work, solid solution alloys of magnesium were exploited as a way to destabilize magnesium hydride thermodynamically. Various elements were alloyed with magnesium to form solid solutions, including: indium (In), aluminum (Al), gallium (Ga), and zinc (Zn). Thermodynamic properties of the reactions between the magnesium solid solution alloys and hydrogen were investigated. Equilibrium pressures were determined by pressure–composition–isothermal (PCI) measurements, showing that all the solid solution alloys that were investigated in this work have higher equilibrium hydrogen pressures than that of pure magnesium. Compared to magnesium hydride, the enthalpy (ΔH) of decomposition to form hydrogen and the magnesium alloy can be reduced from 78.60 kJ/(mol H2) to 69.04 kJ/(mol H2), and the temperature of 1 bar hydrogen pressure can be reduced to 262.33 °C, from 282.78 °C, fo...
TL;DR: Results from this study provide evidence that fucoidan, especially from U. pinnatifida grown in New Zealand, possesses great potential to be used as a functional food to reduce cancer risk or supplement cancer treatment.
Abstract: Undaria pinnatifida is a species of brown seaweed known to contain rich amounts of fucoidan, a sulphated polysaccharide known to possess various biological activities. We isolated crude fucoidan (F0) from the sporophylls of U. pinnatifida grown in the Marlborough Sounds, New Zealand. Sulphate content, uronic acid content and molecular weight of F0 were 15.02%, 1.24% and >150 kDa, respectively. F0 was fractionated to yield three further fractions: F1, F2 and F3. Cytotoxicity of two major fractions was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The algal fucoidans specifically suppressed the proliferation of three cancer cell lines with less cytotoxicity against the normal cells. Selective cytotoxicity could relate to the distinctive structures of each fucoidan fraction. Results from this study provide evidence that fucoidan, especially from U. pinnatifida grown in New Zealand, possesses great potential to be used as a functional food to reduce cancer risk or supplement cancer treatment.