| 1. |
- Wang, Sheng-Jun, 1981-, et al.
(författare)
-
Influence of synaptic interaction on firing synchronization and spike death in excitatory neuronal networks
- 2008
-
Ingår i: Physical Review E. Statistical, Nonlinear, and Soft Matter Physics. - New York : American Physical Society through the American Institute of Physics. - 1063-651X .- 1095-3787. ; 78:6, s. 061906-
-
Tidskriftsartikel (refereegranskat)abstract
- We investigate the influence of efficacy of synaptic interaction on firing synchronization in excitatoryneuronal networks. We find spike death phenomena: namely, the state of neurons transits from the limit cycleto a fixed point or transient state. The phenomena occur under the perturbation of an excitatory synapticinteraction, which has a high efficacy. We show that the decrease of synaptic current results in spike deaththrough depressing the feedback of the sodium ionic current. In the networks with the spike death property thedegree of synchronization is lower and insensitive to the heterogeneity of neurons. The mechanism of theinfluence is that the transition of the neuron state disrupts the adjustment of the rhythm of the neuronsoscillation and prevents a further increase of the firing synchronization.
|
|
| 2. |
- Gidlund, Mikael, et al.
(författare)
-
Uplink Scheduling Algorithms for QoS Support in Broadband Wireless Access Networks
- 2009
-
Ingår i: Journal of Communications. - : Academy Publisher. - 1796-2021 .- 2374-4367. ; 4:2, s. 133-142
-
Tidskriftsartikel (refereegranskat)abstract
- In order to support different types of multimedia applications, the IEEE 802.16 standard defines different service classes with their associated Quality of Service (QoS) parameters. The scheduling algorithm is the crucial point in QoS provisioning over such broadband wireless access (BWA) network and it is important that the scheduling algorithm have a multi-dimensional objective of satisfying QoS requirements of the users, maximizing system utilization and ensuring fairness among users. In this article we present two different scheduling algorithms for the uplink (UL) connection. One is a combination of legacy scheduling algorithms earliest deadline first (EDF) and weighted fair queuing (WFQ). The other proposed algorithm is a cross-layer algorithm that pledges fairness among admitted connections and it also supports all service classes. The proposed scheduling algorithms are compared to several other scheduling algorithms for UL traffic under different mixes of traffic and for various characteristics of the IEEE 802.16 MAC layer such as UL burst preamble, frame length and bandwidth request mechanisms. Simulation results indicate that legacy scheduling algorithms are not suitable for the multi-class traffic in IEEE 802.16 since they do not explicitly incorporate the QoS parameters for the given standard.
|
|
| 3. |
- Huang, Zi-Gang, et al.
(författare)
-
Role of collective influence in promoting cooperation
- 2008
-
Ingår i: Europhysics letters. - Les Ulis : European Physical Society. - 0295-5075 .- 1286-4854. ; 84:5, s. 50008-
-
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.
|
|
| 4. |
- Klionsky, Daniel J., et al.
(författare)
-
Guidelines for the use and interpretation of assays for monitoring autophagy in higher eukaryotes
- 2008
-
Ingår i: Autophagy. - : Landes Bioscience. - 1554-8627 .- 1554-8635. ; 4:2, s. 151-175
-
Forskningsöversikt (refereegranskat)abstract
- Research in autophagy continues to accelerate,1 and as a result many new scientists are entering the field. Accordingly, it is important to establish a standard set of criteria for monitoring macroautophagy in different organisms. Recent reviews have described the range of assays that have been used for this purpose.2,3 There are many useful and convenient methods that can be used to monitor macroautophagy in yeast, but relatively few in other model systems, and there is much confusion regarding acceptable methods to measure macroautophagy in higher eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers of autophagosomes versus those that measure flux through the autophagy pathway; thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from fully functional autophagy that includes delivery to, and degradation within, lysosomes (in most higher eukaryotes) or the vacuole (in plants and fungi). Here, we present a set of guidelines for the selection and interpretation of the methods that can be used by investigators who are attempting to examine macroautophagy and related processes, as well as by reviewers who need to provide realistic and reasonable critiques of papers that investigate these processes. This set of guidelines is not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to verify an autophagic response.
|
|
| 5. |
- Li, Dong-gang, et al.
(författare)
-
Diffusion layer growth at Zn/Cu interface under uniform and gradient high magnetic fields
- 2008
-
Ingår i: Materials Science & Engineering. - : Elsevier BV. - 0921-5093 .- 1873-4936. ; 495:1-2, s. 244-248
-
Tidskriftsartikel (refereegranskat)abstract
- As a common phenomenon occurring in many material processes, diffusion may induce significant changes in composition and microstructure near the interface. In the present study, liquid/solid (Zn/Cu) interface diffusion experiments in high magnetic fields (up to 12 T) were conducted and the thickness changes of diffusion layer under different magnetic field conditions were examined. It was found that there were no noticeable effects of high magnetic fields on the formation of intermetallic phases at the interface. However, the magnetic flux density exerted a non-linear influence on the diffusion layer thickness. This phenomenon should be attributed to the effect of magnetic fields suppressing natural convection and inducing thermo-electromagnetic convection. In addition, the diffusion of Zn into Cu could be retarded by a magnetic field gradient. These results indicate that both the strength and the gradient of high magnetic fields can be used to control the diffusion behavior.
|
|
| 6. |
- Wang, J. H., et al.
(författare)
-
Thermodynamic reassessment of the Au-Te system
- 2006
-
Ingår i: Journal of Alloys and Compounds. - : Elsevier BV. - 0925-8388 .- 1873-4669. ; 407:1-2, s. 106-111
-
Tidskriftsartikel (refereegranskat)abstract
- The Au-Te binary system has been thermodynamically reassessed using the CALPHALD method. The excess Gibbs energy of the liquid phase was formulated with the Redlich-Kister expression and the AuTe2 intermetallic phase was treated as a stoichiometric compound. A set of self-consistent thermodynamic parameters for each phase has been obtained. Good agreement is reached between the calculated and experimental results. Additionally, the standard formation enthalpy and enthalpy of fusion of AuTe2 intermetallic phase have also been calculated.
|
|
| 7. |
- Xu, Min, et al.
(författare)
-
Ototoxicity on cochlear nucleus neurons following systemic application of gentamicin
- 2009
-
Ingår i: Acta Oto-Laryngologica. - : Informa UK Limited. - 1651-2251 .- 0001-6489. ; 129:7, s. 745-748
-
Tidskriftsartikel (refereegranskat)abstract
- Conclusion. The gentamicin-induced pathological alteration in the cochlear nucleus is not exclusively a secondary consequence of the damage in the cochlea. Instead, the toxic effect of gentamicin on the cochlear nucleus may occur simultaneously or even earlier than that on the cochlea. Objectives. To investigate the pathological alteration of cochlear nucleus neurons in guinea pigs following systemic application of gentamicin. Materials and methods. Guinea pigs were injected with gentamicin for I day, 3 days, I week, 2 weeks, and 3 weeks, respectively. In gentamicin-treated animals, the hearing function was evaluated by measuring the auditory brainstem response (ABR). The number and cross-sectional area of substance P-positive neurons in the cochlear nucleus were also measured. Results. The threshold of ABR and the number of substance P-positive neurons in the cochlear nucleus were significantly increased after I week and 3 days of injection of gentamicin, respectively. The cross-sectional area of substance P-positive neurons in the cochlear nucleus was significantly reduced after 1-day injection of gentamicin.
|
|
| 8. |
- Zeng, Xuezhi, et al.
(författare)
-
Silver Ink Patch Antenna for Passive RFID
- 2007
-
Ingår i: Proceedings of ISAP2007, Niigata, Japan. - : IEEE conference proceedings. - 9784885522239 ; , s. 612-615
-
Konferensbidrag (refereegranskat)
|
|
| 9. |
- Zeng, Xuezhi, et al.
(författare)
-
Slots in Metallic Label as RFID Tag Antenna
- 2007
-
Ingår i: IEEE Antennas and Propagation Society, AP-S International Symposium (Digest). - New York : IEEE conference proceedings. - 9781424408771 ; , s. 1600-1603
-
Konferensbidrag (refereegranskat)
|
|
| 10. |
- Zhang, Tingting, et al.
(författare)
-
Bioanalytical characterization of dioxin-like activity in sewage sludge from Beijing, China
- 2009
-
Ingår i: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 75:5, s. 649-653
-
Tidskriftsartikel (refereegranskat)abstract
- In this preliminary study, the bioanalytical characterization of dioxin-like activity in the sludge of all the nine municipal sewage treatment plants from Beijing city Was Studied using chemically activated luciferase gene expression (CALUX) assay. The influence of heating period in winter, sewage and sludge treatment processes on the occurrence of dioxin-like activity was also discussed. For the use of clean coal and natural gas, heating did not have significant influence on the occurrence level of PCDD/Fs and dioxin-like-PCBs in this study. Anaerobic-aerobic-anoxic sewage treatment process did not show a good performance in the reduction of dioxin-like activity which is useful in the removal of chemical oxygen demand (COD) and nitrogen. Anaerobic digestion of sludge increased the concentration of PCDD/Fs from 30.1 to 68.3 pg CALUX-TEQ g(-1) d.w., and total dioxin-like activity from 32.2 to 69.3 pg CALUX-TEQ g(-1) d.w. This cost-effective and quick test is useful for large developing countries like China in monitoring programs to obtain baseline data about the scale of contamination caused by dioxin-like activity. It is also a useful component in the monitoring capacity building of dioxins.
|
|
