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951.
Madelene Lindkvist Mulugeta M. Zegeye Magnus Grenegrd Liza U. Ljungberg 《International journal of molecular sciences》2022,23(3)
Vascular endothelial cells express glycoprotein 130 (gp130), which is utilized as a signaling receptor by cytokines in the interleukin-6 (IL-6) family. Several IL-6 family cytokines can be found in the circulatory system during physiological or pathological conditions, and may influence endothelial function and response. This study evaluated and compared the cellular and molecular responses induced by IL-6 family cytokines in human endothelial cells. A proteomic analysis showed that IL-6 family cytokines induce the release of a range of proteins from endothelial cells, such as C-C motif chemokine ligand 23, hepatocyte growth factor, and IL-6. Pathway analysis indicated that gp130-signaling in endothelial cells regulates several functions related to angiogenesis and immune cell recruitment. The present investigation also disclosed differences and similarities between different IL-6 family cytokines in their ability to induce protein release and regulate gene expression and intracellular signaling, in regards to which oncostatin M showed the most pronounced effect. Further, this study showed that soluble gp130 preferentially blocks trans-signaling-induced responses, but does not affect responses induced by classic signaling. In conclusion, IL-6 family cytokines induce both specific and overlapping molecular responses in endothelial cells, and regulate genes and proteins involved in angiogenesis and immune cell recruitment. 相似文献
952.
W. Schfer U. Rosenfeld H. Zaschke H. Stettin H. Kresse 《Advanced Synthesis \u0026amp; Catalysis》1989,331(4):631-636
Liquid Crystalline 1,3,4-Thiadiazoles. II. 1,3,4-Thiadiazoles with Cyclohexanefragments Preparation and liquid crystalline properties of disubstituted 1,3,4-thiadiazoles (1 and 2) are described. The mesomorphic behaviour of the title compounds is compared with their benzoate analogues. The dielectric anisotropy of these compounds is negative. 相似文献
953.
Poya Kavianpour Madeleine C. M. Gemmell Dr. Jan U. Kahlert Prof. Louis M. Rendina 《Chembiochem : a European journal of chemical biology》2020,21(19):2786-2791
Histone deacetylase enzymes (HDACs) are responsible for the global silencing of tumour-suppressor genes. Treatment with a histone deacetylase inhibitor (HDACi) can reverse this process and restore normal cell function. Herein, we report a small series of boron-based (boronic acid, boronate ester and closo-1,2-carborane) HDAC2 inhibitors with IC50 values in the nanomolar range. The boronate ester 4 b was the most potent compound assessed in this study (IC50=40.6±1.5 nM), followed closely by the 1,2-closo-carborane (IC50=42.9±1.5 nM). Compound 4 b exceeds the potency of the related gold-standard HDAC pan-inhibitor vorinostat ( 1 ) toward this particular HDAC isoform. 相似文献
954.
Hugo R. Fernandes Anuraag Gaddam Dilshat U. Tulyaganov José M. F. Ferreira 《International Journal of Applied Ceramic Technology》2020,17(1):64-74
Recycling has emerged as an environmental key point due to the diminishing of natural resources and the generation of ever-increasing amounts of industrial solid wastes. Glass wastes are among the materials that attract great interest in the recycling concept. This work presents the results of foams production from four series of compositions. The first series comprises powders of a sodium-calcium-silicate sheet glass cullet as the main component, an alkali-earth aluminosilicate glass as an additive, and a reagent grade silicon carbide (SiC) powder as gassing agent. In the second series, the glass cullet was used in combination with fly ashes (FLA) as main components, while SiC waste from abrasive paper served as foaming agent. In the third and fourth series, carbonates (calcite and dolomite) were used for foaming powder mixtures composed of sheet glass cullet and FLA, and powdered cathode ray tube panel glasses, respectively. All the processing parameters, including the main components, the nature and content of foaming agents are shown to play a crucial role on the foaming ability and final properties of the glass foams. 相似文献
955.
U.-W. Grummt 《Advanced Synthesis \u0026amp; Catalysis》1995,337(1):520-520
956.
957.
Mass transfer and electrocrystallization analyses of nanocrystalline nickel production by pulse plating 总被引:4,自引:0,他引:4
R. T. C. Choo J. M. Toguri A. M. El-Sherik U. Erb 《Journal of Applied Electrochemistry》1995,25(4):384-403
A comparison between the experimental process parameters employed for the pulse plating of nanocrystalline nickel and the solution-side mass transfer and electrokinetic characteristics has been carried out. It was found that the experimental process parameters (on-time, off time and cathodic pulse current density) for cathodic rectangular pulses are consistent and within the physical constraints (limiting pulse current density, transition time, capacitance effects and integrity of the waveform) predicted from theory with the adopted postulates. This theoretical analysis also provides a means of predicting the behaviour of the process subject to a change in the system, kinetic and process parameters. The product constraints (current distribution, nucleation rate and grain size), defined as the experimental conditions under which nanocrystalline grains are produced, were inferred from electrocrystallization theory. High negative overpotential, high adion population and low adion surface mobility are prerequisites for massive nucleation rates and reduced grain growth; conditions ideal for nanograin production. Pulse plating can satisfy the former two requirements but published calculations show that surface mobility is not rate-limiting under high negative overpotentials for nickel. Inhibitors are required to reduce surface mobility and this is consistent with experimental findings. Sensitivity analysis on the conditions which reduce the total overpotential (thereby providing more energy for the formation of new nucleation sites) are also carried out. The following lists the effect on the overpotential in decreasing order: cathodic duty cycle, charge transfer coefficient, Nernst diffusion thickness, diffusion coefficient, kinetic parameter () and exchange current density.Nomenclature
A
constant employed in Fig. 8, (nFi0)/(RT
e
C
a)(s–1)
-
B
constant in Equation 38 (V2)
-
C
cation concentration (molcm–3)
-
C
a
capacitance of double layer (µFcm–2)
-
C
s
cation surface concentration (molcm–3)
-
C
s
*
dimensionless cation surface concentration, C
s/C
(–)
-
C
cation bulk concentration (molcm–3)
-
D
diffusion coefficient of cation (cm2s–1)
- E
total applied potential (V)
- E
0
standard cell potential (V)
-
F
Faraday constant (Cmol–1)
-
function defined in Appendix C(–)
-
Fr
frequency of waveform (Hz)
-
f
i,p
function defined in Appendix C for pth period (–)
-
f
i,
function defined in Appendix C for p period (–)
-
G
j
function defined in Appendix B (–)
-
gi
function defined in Appendix B (–)
-
i
current density (Acm¨)
-
i
ac
unsteady fluctuating a.c. current density (Acm–2)
-
i
c
capacitance current density (Acm–2)
-
i
dc
steady time-averaged d.c. current density (Acm–2)
-
i
F
Faradaic current density (Acm–2)
-
i
lim
limiting d.c. current density (Acm–2)
-
i
0
exchange current density (Acm–2)
-
i
PL
limiting pulse current density, i
1{Cs = 0 at t = (p – 1) T + t
1(Acm–2)
-
i
1
cathodic pulse current density (Acm–2)
-
i
2
relaxed or low current pulse current density (Acm–2)
-
iin
anodic pulse current density (Acm–2)
-
i
*
dimensionless current density, i/|i
lim| (–)
-
i
0
*
dimensionless exchange current density, i
dc/|i
lim| (–)
-
i
dc
*
dimensionless steady time-averaged d.c. current density, i
dc/|i
lim| (–)
-
i
PL
*
dimensionless limiting cathodic pulse current density, i
PL/|i
lim| (–)
-
i
PL,p
*
dimensionless limiting pulse current density at pth period, i
1(C
s = 0)/|i
lim| (–)
-
i
PL,
*
dimensionless limiting pulse current density for p , i
1(C
s = 0)/|i
lim| (–)
-
i
1
*
dimensionless cathodic pulse current density, i
1/|i
lim| (–) 相似文献
958.
Seely JF Szabo CI Feldman U Hudson LT Henins A Audebert P Brambrink E 《The Review of scientific instruments》2010,81(10):10E301
The transmission crystal spectrometer (TCS) is approved for taking data at the OMEGA-EP laser facility since 2009 and will be available for the OMEGA target chamber in 2010. TCS utilizes a Cauchois type cylindrically bent transmission crystal geometry with a source to crystal distance of 600 mm. Spectral images are recorded by image plates in four positions, one IP on the Rowland circle and three others at 200, 400, and 600 mm beyond the Rowland circle. An earlier version of TCS was used at LULI on experiments that determined the x-ray source size from spectral line broadening on one IP positioned behind the Rowland circle. TCS has recorded numerous backlighter spectra at EP for point projection radiography and for source size measurements. Hard x-ray source size can be determined from the source broadening of both K shell emission lines and from K absorption edges in the bremsstrahlung continuum, the latter being a new way to measure the spatial extent of the hard x-ray bremsstrahlung continuum. 相似文献
959.
介绍了第三代同步辐射高分辨率X射线衍射光束线的总体设计。给出了高分辨率衍射的基本原理并描述了获得确定光子能量的近平行高强度X射线光束线所必需的光学元件。特别是用X射线动力学理论,解释了双晶及四次反射晶体单色器。作为一个实例,介绍了将于2009年开始在德国汉堡运行的一个新的同步辐射源PETRAⅢ的高分辨率衍射(HighRes)光束线的设置情况。通过优化光学部件,对微米尺寸光束,q空间的分辨减小到Δq=10-5 nm-1,光通量大于1011 cts/s。 相似文献
960.
Efficiency of activated carbon to transform ozone into *OH radicals: influence of operational parameters 总被引:3,自引:0,他引:3
Based on previous findings (Jans, U., Hoigné, J., 1998. Ozone Sci. Eng. 20, 67-87), the activity of activated carbon for the transformation of ozone into *OH radicals including the influence of operational parameters (carbon dose, ozone dose, carbon-type and carbon treatment time) was quantified. The ozone decomposition constant (k(D)) was increased by the presence of activated carbon in the system and depending on the type of activated carbon added, the ratio of the concentrations of *OH radicals and ozone, the R(ct) value ([*OH]/[O3]), was increased by a factor 3-5. The results obtained show that the surface chemical and textural characteristics of the activated carbon determines its activity for the transformation of ozone into *OH radicals. The most efficient carbons in this process are those with high basicity and large surface area. The obtained results show that the interaction between ozone and pyrrol groups present on the surface of activated carbon increase the concentration of O2*- radicals in the system, enhancing ozone transformation into *OH radicals. The activity of activated carbon decreases for extended ozone exposures. This may indicate that activated carbon does not really act as a catalyst but rather as a conventional initiator or promoter for the ozone transformation into *OH radicals. Ozonation of Lake Zurich water ([O3] = 1 mg/L) in presence of activated carbon (0.5 g/L) lead to an increase in the k(D) and R(ct) value by a factor of 10 and 39, respectively, thereby favouring the removal of ozone-resistant contaminants. Moreover, the presence of activated carbon during ozonation of Lake Zurich water led to a 40% reduction in the content of dissolved organic carbon during the first 60 min of treatment. The adsorption of low concentrations of dissolved organic matter (DOM) on activated carbon surfaces did not modify its capacity to initiate/promote ozone transformation into *OH radicals. 相似文献