| 1. |
- Huang, Zi-Gang, et al.
(författare)
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Role of collective influence in promoting cooperation
- 2008
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Ingår i: Europhysics letters. - Les Ulis : European Physical Society. - 0295-5075 .- 1286-4854. ; 84:5, s. 50008-
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Tidskriftsartikel (refereegranskat)abstract
- The collective influence on the individuals' behavior have attracted much attention, and interesting phenomena such as social facilitation and social loafing have been studied. In this paper, we consider how the collective influence affects the evolution of cooperation in a structured population of individuals who nourish and benefit from public goods in groups. Individuals are supposed to distribute endowments to different groups to nourish the corresponding public goods. The collective influence is indicated by a tunable parameter α, with larger α corresponding to the players' higher preference to contribute more to the larger groups, which is similar to the social-facilitation effect in the real world, whereas, with smaller α corresponding to individuals' contrary preference, i.e., the social-loafing effect. Interestingly, we find that the heterogeneity of public-goods setting favors cooperation. Furthermore, the system where social loafing occurs performs better than that with social facilitation, in the case of heterogeneous formation.
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| 2. |
- Gao, Bin, et al.
(författare)
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Spectral identification of fullerene C82 isomers
- 2007
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Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 127:16, s. 164314-1-164314-8
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Tidskriftsartikel (refereegranskat)abstract
- Ultraviolet photoelectron spectra (UPS) of C-82 isomers have been calculated using hybrid density functional theory in combination with the Gelius model [Proceedings of the International Conference on Electron spectroscopy, edited by D. A. Shirley (North-Holland, Amsterdam, 1972), p. 311; J. Electron Spectrosc. Relat. Phenom. 5, 985 (1974)]. The calculated UPS spectra are found to be isomer dependent and in good agreement with the experimental counterparts. Near-edge x-ray absorption fine structure (NEXAFS), x-ray photoelectron spectroscopy (XPS), x-ray emission spectroscopy, and the resonant inelastic x-ray scattering (RIXS) spectra of three important isomers [3(C-2), 6(C-s), and 9(C-2v)] have also been simulated. Strong isomer dependence has also been found for NEXAFS, XPS, and RIXS spectra.
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| 3. |
- Liu, Lei, et al.
(författare)
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The structural determination of endohedral metallofullerene Gd@C-82 by XANES
- 2008
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Ingår i: Chemical Communications. - : Royal Society of Chemistry (RSC). - 1359-7345 .- 1364-548X. ; :4, s. 474-476
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Tidskriftsartikel (refereegranskat)abstract
- Although the Gd ion in Gd@C-82 has been shown to lie above the C-C bond on the C-2 axis as an anomalous structure from the MEM/Rietveld analysis, the present XANES study reveals that it lies above the hexagon on the C-2 axis as a normal structure, and Gd oscillates around its equilibrium position with an amplitude increasing with temperature increase.
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| 4. |
- Nordberg, Gunnar F, et al.
(författare)
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Prevalence of kidney dysfunction in humans - relationship to cadmium dose, metallothionein, immunological and metabolic factors.
- 2009
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Ingår i: Biochimie. - : Elsevier BV. - 1638-6183 .- 0300-9084. ; 91:10, s. 1282-5
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Tidskriftsartikel (refereegranskat)abstract
- Long term cadmium (Cd) exposure in occupational and general environments may give rise to kidney dysfunction. This effect is usually considered to be the critical effect, i. e. the effect that occurs at relatively low level of exposure. The present review focused on studies of the prevalence of cadmium-related kidney dysfunction among population groups residing in cadmium contaminated areas in China. Dose-response relationships were shown between UCd and the prevalence of increased levels of biomarkers in urine of renal tubular dysfunction such as urinary beta-2-microglobulin or N-acetyl-beta-d-glucosaminidase - NAG or urinary albumin, a biomarker of glomerular kidney dysfunction. Factors that influence these dose-response relationships include: 1) Metallothionein mRNA levels in peripheral blood lymphocytes, used as a biomarker of the ability of each person, to synthesize metallothionein (a protein known to provide intracellular protection against cadmium toxicity). 2) The occurrence of increased levels in blood plasma of autoantibodies against metallothionein. 3) Concomitant changes in glucose metabolism i e Type II diabetes. 4) Concomitant exposure to other nephrotoxic agents such as inorganic arsenic. Increased susceptibility in diabetics has been shown also in population groups in Europe. In persons with type II diabetes and increased levels of autoantibodies against metallothionein in blood plasma or in persons with concomitant exposure to environmental inorganic arsenic, indications of Cd-related kidney dysfunction was observed at UCd levels around 1 microg/g creatinine, levels found among "unexposed" population groups in many countries.
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| 5. |
- Orrú, Valeria, et al.
(författare)
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A loss-of-function variant of PTPN22 is associated with reduced risk of systemic lupus erythematosus
- 2009
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Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 18:3, s. 569-579
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Tidskriftsartikel (refereegranskat)abstract
- A gain-of-function R620W polymorphism in the PTPN22 gene, encoding the lymphoid tyrosine phosphatase LYP, has recently emerged as an important risk factor for human autoimmunity. Here we report that another missense substitution (R263Q) within the catalytic domain of LYP leads to reduced phosphatase activity. High-resolution structural analysis revealed the molecular basis for this loss of function. Furthermore, the Q263 variant conferred protection against human systemic lupus erythematosus, reinforcing the proposal that inhibition of LYP activity could be beneficial in human autoimmunity.
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| 6. |
- Wu, Xunwei, et al.
(författare)
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Renal effects evolution in a Chinese population after reduction of cadmium exposure in rice.
- 2008
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Ingår i: Environmental research. - : Elsevier BV. - 1096-0953 .- 0013-9351. ; 108:2, s. 233-8
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Tidskriftsartikel (refereegranskat)abstract
- Cadmium is a well-known nephrotoxic agent with extremely long biological half-time of 10-30 years in human. To investigate the evolution of cadmium-induced renal effects in the population, a number of 148 residents who lived in cadmium-polluted area were followed-up for 3 years after the reduction of cadmium exposure in rice. Urinary cadmium (UCd), beta(2)-microglobulin (B2M) and albumin (ALB) were analyzed in 1995 and 1998, respectively. The results demonstrated that the changes of renal effects of residents depended on the levels of UCd before inflow of cadmium to human body declined. In cases where UCd were less than 10 microg/g creatinine in 1995, evidence was found indicating significant decreases in proteinuria (i.e., B2M and ALB) 3 years later, whereas, in cases where the excretion of UCd exceeded 10 microg/g creatinine in 1995, progression was observed. The study of dose-response relationships between UCd and B2M or ALB also showed that the cadmium-induced renal dysfunction might be reversible if UCd concentration was low-level before exposure decreasing, otherwise it might be irreversible or aggravated.
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| 7. |
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| 8. |
- You, Lei, et al.
(författare)
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Dynamic Control and Resource Allocation in Wireless-Infrastructured Distributed Cellular Networks with OFDMA
- 2009
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Ingår i: 2009 INTERNATIONAL CONFERENCE ON PARALLEL PROCESSING WORKSHOPS (ICPPW 2009). - 9781424449231 ; , s. 337-343
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Konferensbidrag (refereegranskat)abstract
- In this paper, we consider joint optimization of end-to-end data transmission and resource allocation for Wireless-Infrastructured Distributed Cellular Networks (WIDCNs), where each base station (BS) in a cell is connected with its neighboring BSs via wireless links, and a mobile station (MS) can access one or multiple adjacent BSs simultaneously through time-varying OFDMA channels. The communications between a source MS and a destination MS are carried out with the help of BSs in the multi-hop, distributed manner. To achieve the joint optimization for such WIDCNs, a Stochastic Network Utility Maximization (SNUM) problem is formulated under the constraints of OFDMA sub-channel allocation on time-varying access links (both uplink and downlink), as well as routing and scheduling on forwarding links among BSs. By decomposing the corresponding dual problem, transforming it into a stochastic convex optimization problem and solving it by quasi-gradient method, we obtain distributed dynamic control algorithms for end-to-end data transmission. The algorithm can adapt to the OFMDA channel variation and converges asymptotically to the optimal solution. We also develop a distributed algorithm for OFDMA sub-channel allocation and link coordination between BSs. The simulation results show that the data rates of the flows can converge to optimal solution approximately, queues of the network is stable under the proposed distributed dynamic algorithm, and the multi-receiver scheme outperforms the single-receiver scheme due to diversity.
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| 9. |
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