3,795 research outputs found
Signatures of strong correlation effects in RIXS on Cuprates
Recently, spin excitations in doped cuprates are measured using the resonant
inelastic X-ray scattering (RIXS). The paramagnon dispersions show the large
hardening effect in the electron-doped systems and seemingly
doping-independence in the hole-doped systems, with the energy scales
comparable to that of the antiferromagnetic magnons. This anomalous hardening
effect was partially explained by using the strong coupling t-J model but with
a three-site term(Nature communications 5, 3314 (2014)). However we show that
hardening effect is a signature of strong coupling physics even without
including this extra term. By considering the t-t'-t"-J model and using the
Slave-Boson (SB) mean field theory, we obtain, via the spin-spin
susceptibility, the spin excitations in qualitative agreement with the
experiments. These anomalies is mainly due to the doping-dependent bandwidth.
We further discuss the interplay between particle-hole-like and paramagnon-like
excitations in the RIXS measurements.Comment: 7 pages, 6 figure
Joint and Cross-border Patents as Proxies for International Technology Diffusion
With the advent of globalization, economic and financial interactions among countries have become widespread. Given technological advancements, the factors of production can no longer be considered to be just labor and capital. In the pursuit of economic growth, every country has sensibly invested in international cooperation, learning, innovation, technology diffusion and knowledge, and outward direct investment. In this paper, we use a panel data set of 40 countries from 1981 to 2008 and a negative binomial model, using a novel set of cross-border patents and joint patents as proxy variables for technology diffusion, in order to investigate such diffusion. The empirical results suggest that, if it is desired to shift from foreign to domestic technology, it is necessary to increase expenditure on R&D for business enterprises and higher education, exports and technology. If the focus is on increasing bilateral technology diffusion, it is necessary to increase expenditure on R&D for higher education and technology. It is also found that outward foreign direct investment has no significant impact on either joint or cross-border patents, whereas inward foreign direct investment has a significant negative impact on cross-border patents but no impact on joint patents. Moreover, government expenditure on higher education has a significant impact on both cross-border and joint patents
International Technology Diffusion of Joint and Cross-border Patents (Revised version)
With the advent of globalization, economic and financial interactions among countries have become widespread. Given technological advancements, the factors of production can no longer be considered to be just labor and capital. In the pursuit of economic growth, every country has sensibly invested in international cooperation, learning, innovation, technology diffusion and knowledge. In this paper, we use a panel data set of 40 countries from 1981 to 2008 and a negative binomial model, using a novel set of cross-border patents and joint patents as proxy variables for technology diffusion, in order to investigate such diffusion. The empirical results suggest that, if it is desired to shift from foreign to domestic technology, it is necessary to increase expenditure on R&D for business enterprises and higher education, exports and technology. If the focus is on increasing bilateral technology diffusion, it is necessary to increase expenditure on R&D for higher education and technology
International Technology Diffusion of Joint and Cross-border Patents
With the advent of globalization, economic and financial interactions among countries have become widespread. Given technological advancements, the factors of production can no longer be considered to be just labor and capital. In the pursuit of economic growth, every country has sensibly invested in international cooperation, learning, innovation, technology diffusion and knowledge. In this paper, we use a panel data set of 40 countries from 1981 to 2008 and a negative binomial model, using a novel set of cross-border patents and joint patents as proxy variables for technology diffusion, in order to investigate such diffusion. The empirical results suggest that, if it is desired to shift from foreign to domestic technology, it is necessary to increase expenditure on R&D for business enterprises and higher education, exports and technology. If the focus is on increasing bilateral technology diffusion, it is necessary to increase expenditure on R&D for higher education and technology
GPER-induced signaling is essential for the survival of breast cancer stem cells.
G protein-coupled estrogen receptor-1 (GPER), a member of the G protein-coupled receptor (GPCR) superfamily, mediates estrogen-induced proliferation of normal and malignant breast epithelial cells. However, its role in breast cancer stem cells (BCSCs) remains unclear. Here we showed greater expression of GPER in BCSCs than non-BCSCs of three patient-derived xenografts of ER- /PR+ breast cancers. GPER silencing reduced stemness features of BCSCs as reflected by reduced mammosphere forming capacity in vitro, and tumor growth in vivo with decreased BCSC populations. Comparative phosphoproteomics revealed greater GPER-mediated PKA/BAD signaling in BCSCs. Activation of GPER by its ligands, including tamoxifen (TMX), induced phosphorylation of PKA and BAD-Ser118 to sustain BCSC characteristics. Transfection with a dominant-negative mutant BAD (Ser118Ala) led to reduced cell survival. Taken together, GPER and its downstream signaling play a key role in maintaining the stemness of BCSCs, suggesting that GPER is a potential therapeutic target for eradicating BCSCs
Proteomic analysis of rhein-induced cyt: ER stress mediates cell death in breast cancer cells
Rhein is a natural product purified from herbal plants such as Rheum palmatum, which has been shown to have anti-angiogenesis and anti-tumor metastasis properties. However, the biological effects of rhein on the behavior of breast cancers are not completely elucidated. To evaluate whether rhein might be useful in the treatment of breast cancer and its cytotoxic mechanism, we analyzed the impact of rhein treatment on differential protein expression as well as redox regulation in a non-invasive breast cancer cell line, MCF-7, and an invasive breast cancer cell line, MDA-MB-231, using lysine- and cysteine-labeling two-dimensional difference gel electrophoresis (2D-DIGE) combined with MALDI-TOF/TOF mass spectrometry. This proteomic study revealed that 73 proteins were significantly changed in protein expression; while 9 proteins were significantly altered in thiol reactivity in both MCF-7 and MDA-MB-231 cells. The results also demonstrated that rhein-induced cytotoxicity in breast cancer cells mostly involves dysregulation of cytoskeleton regulation, protein folding, the glycolysis pathway and transcription control. A further study also indicated that rhein promotes misfolding of cellular proteins as well as unbalancing of the cellular redox status leading to ER-stress. Our work shows that the current proteomic strategy offers a high-through-put platform to study the molecular mechanisms of rhein-induced cytotoxicity in breast cancer cells. The identified differentially expressed proteins might be further evaluated as potential targets in breast cancer therapy
Joint and Cross-border Patents as Proxies for International Technology Diffusion
With the advent of globalization, economic and financial interactions among countries have become widespread. Given technological advancements, the factors of production can no longer be considered to be just labor and capital. In the pursuit of economic growth, every country has sensibly invested in international cooperation, learning, innovation, technology diffusion and knowledge, and outward direct investment. In this paper, we use a panel data set of 40 countries from 1981 to 2008 and a negative binomial model, using a novel set of cross-border patents and joint patents as proxy variables for technology diffusion, in order to investigate such diffusion.
The empirical results suggest that, if it is desired to shift from foreign to domestic technology, it is necessary to increase expenditure on R&D for business enterprises and higher education, exports and technology. If the focus is on increasing bilateral technology diffusion, it is necessary to increase expenditure on R&D for higher education and technology. It is also found that outward foreign direct investment has no significant impact on either joint or cross-border patents, whereas inward foreign direct investment has a significant negative impact on cross-border patents but no impact on joint patents. Moreover, government expenditure on higher education has a significant impact on both cross-border and joint patent
International Technology Diffusion of Joint and Cross-border Patents
__Abstract__
With the advent of globalization, economic and financial interactions among countries
have become widespread. Given technological advancements, the factors of production
can no longer be considered to be just labor and capital. In the pursuit of economic
growth, every country has sensibly invested in international cooperation, learning,
innovation, technology diffusion and knowledge. In this paper, we use a panel data set
of 40 countries from 1981 to 2008 and a negative binomial model, using a novel set of
cross-border patents and joint patents as proxy variables for technology diffusion, in
order to investigate such diffusion. The empirical results suggest that, if it is desired to
shift from foreign to domestic technology, it is necessary to increase expenditure on
R&D for business enterprises and higher education, exports and technology. If the
focus is on increasing bilateral technology diffusion, it is necessary to increase
expenditure on R&D for higher education and technology
ATP-Binding Cassette Transporter VcaM from Vibrio cholerae is Dependent on the Outer Membrane Factor Family for Its Function.
Vibrio cholerae ATP-binding cassette transporter VcaM (V. cholerae ABC multidrug resistance pump) has previously been shown to confer resistance to a variety of medically important drugs. In this study, we set to analyse its properties both in vitro in detergent-solubilised state and in vivo to differentiate its dependency on auxiliary proteins for its function. We report the first detailed kinetic parameters of purified VcaM and the rate of phosphate (Pi) production. To determine the possible functional dependencies of VcaM on the tripartite efflux pumps we then utilized different E. coli strains lacking the principal secondary transporter AcrB (Acriflavine resistance protein), as well as cells lacking the outer membrane factor (OMF) TolC (Tolerance to colicins). Consistent with the ATPase function of VcaM we found it to be susceptible to sodium orthovanadate (NaOV), however, we also found a clear dependency of VcaM function on TolC. Inhibitors targeting secondary active transporters had no effects on either VcaM-conferred resistance or Hoechst 33342 accumulation, suggesting that VcaM might be capable of engaging with the TolC-channel without periplasmic mediation by additional transporters. Our findings are indicative of VcaM being capable of a one-step substrate translocation from cytosol to extracellular space utilising the TolC-channel, making it the only multidrug ABC-transporter outside of the MacB-family with demonstrable TolC-dependency
Potassium {4-[(3S,6S,9S)-3,6-dibenzyl-9-isopropyl-4,7,10-trioxo-11–oxa-2,5,8-triazadodecyl]phenyl}trifluoroborate
[[abstract]]The reported compound 4 was synthesized and fully characterized by 1H NMR, 13C NMR, 11B NMR, 19F NMR, and high resolution mass spectrometry.[[booktype]]電子版[[countrycodes]]CH
- …
