A Novel QoS Guarantee Mechanism in IEEE 802.16 Mesh Networks

IEEE 802.16 defines perfect QoS (Quality of Service) guarantee mechanism in PMP (Point to Multi-Point) mode and denotes mesh mode cannot provide this capability. To resolve this problem of WiMAX Mesh network, a novel QoS guarantee mechanism including protocol process and minislot allocation algorithm is proposed. This mechanism uses existing service classes in original standard. Protocol processes that manage dynamic service flow are defined. WiMAX MAC layer is re-designed to support service classification in mesh mode. Using extended distributed scheduling messages, the delivery method of dynamic service management messages in WiMAX mesh networks is implemented. Minislot allocation algorithm is given to support data scheduling of various services. Service establishment time is analyzed in this paper. The simulation result shows that the mechanism can provide QoS in WiMAX mesh networks effectively

Changes of plasma fibroblast growth factor-21 (FGF-21) in oral glucose tolerance test and effects of metformin on FGF-21 levels in type 2 diabetes mellitus

Wstęp: Badanie przeprowadzono w celu ustalenia, czy czynnik wzrostu fibroblastów-21 (FGF-21) uczestniczy w regulacji stężenia glukozy i czy zastosowanie metforminy u chorych na cukrzycę wpływa na stężenie FGF-21. Materiał i metody: Do badania włączono 43 osoby, w tym 27 chorych z nowo rozpoznaną cukrzycą typu 2 (nT2DM). U wszystkich przeprowadzono test doustnego obciążenia 75 g glukozy (OGTT). Próbki krwi pobrano w 0., 60.,120. i 180. minucie testu. Osobom z nT2DM zaproponowano udział w dalszych badaniach; zastosowano u nich metforminę w dawce 1,0 g/dobę przez tydzień. Wyniki: Zmiany stężenia FGF-21 w osoczu podczas OGTT zaobserwowano tylko w grupie chorych na nT2DM; w grupie kontrolnej stężenie FGF-21 pozostało niezmienione. Nie stwierdzono, by stężenia FGF-21 w poszczególnych punktach czasowych różniły się w zależności od płci badanych (p < 0,05). Zastosowanie metforminy u osób z nT2DM spowodowało istotne zmniejszenie stężeń glukozy i FGF-21 we wszystkich punktach czasowych OGTT oraz zmniejszenie stężenia insuliny w 60. i 180. minucie, co wskazuje na obniżenie wskaźnika HOMA-IR. Wnioski: FGF-21 nie uczestniczy w krótkoterminowej regulacji glikemii u ludzi, a zmiany jego stężenia podczas OGTT są opóźnione w T2DM. Być może FGF-21 bierze udział w metabolizowaniu metforminy, zwiększając wrażliwość na glukozę i insulinę. (Endokrynol Pol 2013; 64 (3): 220&#8211;224)Introduction: The objectives of our study were to investigate whether fibroblast growth factor-21 (FGF-21) is involved in short-term regulation of glucose and the change of FGF-21 after metformin use in diabetic subjects. Material and methods: 43 subjects were recruited in the study, including 27 new-onset type 2 diabetes patients (nT2DM). A 75 g oral glucose tolerance test (OGTT) was administered to them. Blood samples were taken at 0, 60 ,120 and 180 minute of OGTT. nT2DM subjects were invited for further investigation, metformin was administered in a dose of 1.0 g every day for 1 week. Results: Plasma FGF-21 changed significantly in the nT2DM group during the OGTT administration but not in the control group. No gender differences were observed at different time points in FGF-21 levels (p < 0.05). Administration of metformin for nT2DM resulted in a significant decrease in both glucose and FGF-21 at all OGTT times and in insulin at 60 min and 180 min, indicative of a decrease in HOMA-IR. Conclusion: FGF-21 does not seem to be involved in short-term regulation of glycaemia in human subjects, and the change in OGTT delayed in T2DM. FGF-21 may participate in the processing of metformin, improving glucose and insulin sensitivity. (Pol J Endocrinol 2013; 64 (3): 220&#8211;224

A phase transition driven by subtle distortion without broken symmetry on spin, charge and lattice in Layered LnCu4-{\delta}P2(Ln=Eu, Sr)

In the scenario of Landau phase transition theory in condensed matter physics, any thermal dynamic phase transition must be subject to some kind of broken symmetries, that are relative to its spin, charge, orbital and lattice. Here we report a rare phase transition at Tp ~120 K or 140 K in layered materials LnCu4-{\delta}P2 (Ln=Eu, Sr) driven by a subtle structural-distortion without any broken symmetry on charge, spin and lattice. The variations of the lattice parameters, ({\Delta}Lc/Lc) ~ 0.013% or 0.062%, verified by thermal expansion, is much less than that for a typical crystalline phase transition (~0.5-1%), but the significant anomaly in heat capacity provides clear evidence of its intrinsic nature of thermodynamic transition.Comment: 13 pages, 4 figure

Photodynamic therapy combined with the Sanqi Panax Notoginseng for patients with age-related macular degeneration and choroidal neovascularization

AIM: To investigate the clinical effect of photodynamic therapy(PDT)combined with Traditional Chinese medicine Sanqi Panax Notoginseng therapy for age-related macular degeneration(AMD)and choroidal neovascularization(CNV). <p>METHODS: Seventeen patients(17 eyes)with AMD and CNV were diagnosed by visual acuity, ocular pressure, fundus fluorescein angiography(FFA), idocyanine green angiography(ICGA)and optic coherence tomography(OCT), and male 7 cases, female 10 cases, age 53-72 years old. PDT was performed using the recommended standard procedure. The patients were treated with PDT for 5 days, and Sanqi Panax Notoginseng 500mg injection by intravenous drip for 10 days, once a day, 15 days as one course. One month, 3, 6 months of follow-up after treatment. <p>RESULTS: Of 17 patients after 6 months treatment, visual acuity improved in 8 cases(47%, 8/17), remained stable in 6 cases(35%), and decreased in 3 cases(18%); and 12 cases(71%)with CNV closure and leakage stopped completely, 5 cases(29%)with most of the CNV's closure, 1 patient experienced blurred vision. <p>CONCLUSION: The results show that PDT combined with traditional Chinese medicine Sanqi Panax Notoginseng in treatment of ADM-CNV is simple and has reliable effect, it can be used in clinical application

An Evaluation on Bridge Bearing Capacity under Scour and Re-occurrence of Strong Earthquake

Plagued by frequent calamities, Bridge No.3 encountered magnitude-8 earthquake on May 12, 2008 and several years later its pile foundation was intensively scoured. The smallest scour depth was 4.5 meters and the largest scour depth was 9.2 meters. Considering intense scour and re-occurrence of strong earthquake, the Chinese existing standard and seismic response analysis are used to study bearing capacity and seismic performance of pier and pile foundation of Bridge No.3 before and after scour. It is proved by calculation that the bridge is stable before scour and can hardly bear strong earthquake and intense scour after scour, therefore consolidation is required. The study result may serve as an important reference for the bridge affected by serious scour and strong earthquake

Mechanism underlying synergic activation of Tyrosinase promoter by MITF and IRF4

Background: The transcription factor interferon regulatory factor 4 (IRF4) was identified to be involved in human pigmentation by genome-wide association studies (GWASs). The rs12203592-[T/C], which is located in intron 4 of IRF4, shows the strongest link to these pigmentation phenotypes including freckling, sun sensitivity, eye and hair color. Previous studies indicated a functional cooperation of IRF4 with Microphthalmia-associated transcription factor (MITF), a causing gene of Waardenburg syndrome (WS), to synergistically trans-activate Tyrosinase (TYR). However, the underlying mechanism is still unknown. Methods: To investigate the importance of DNA binding in the synergic effect of IRF4. Reporter plasmids with mutant TYR promoters was generated to locate the IRF4 DNA binding sites in the Tyrosinase minimal promoter. By building MITF and IRF4 truncated mutations plasmids, the necessary regions of the synergy functions of these two proteins were also located. Results: The cooperative effect between MITF and IRF4 was specific for TYR promoter. The DNA-binding of IRF4 was critical for the synergic function. IRF4 DNA binding sites in TYR promoter were identified. The Trans-activation domains in IRF4 (aa134-207, aa300-420) were both important for the synergic function, whereas the auto-mask domain (aa207-300) appeared to mask the synergic effect. Mutational analysis in MITF indicated that both DNA-binding and transcriptional activation domains were both required for this synergic effect. Conclusions: Here we showed that IRF4 potently synergized with MITF to activate the TYR promoter, which was dependent on DNA binding of IRF4. The synergic domains in both IRF4 and MITF were identified by mutational analysis. This identification of IRF4 as a partner for MITF in regulation of TYR may provide an important molecular function for IRF4 in the genesis of melanocytes and the pathogenic mechanism in WS

Biosynthesis of arsenolipids by the cyanobacterium Synechocystis sp. PCC 6803

Although methylated arsenic and arsenosugars have been verified in various freshwater organisms, lipid-soluble arsenic compounds have not been identified. Here, we report investigations with the model organism cyanobacterium Synechocystis sp. PCC 6803 wild type and arsM (arsenic(III) S-adenosylmethionine methyltransferase) mutant strain, which lacks the enzymes for arsenic methylation cultured in various concentrations of arsenate (As-V). Although Synechocystis accumulated higher arsenic concentrations at the higher exposure levels, the bioaccumulation factor decreased with increasing As-V. The accumulated arsenic in the cells was partitioned into water-soluble and lipid-soluble fractions; lipid-soluble arsenic was found in Synechocystis wild type cells (3-35% of the total depending on the level of arsenic exposure), but was not detected in Synechocystis arsM mutant strain showing that ArsM was required for arsenolipid biosynthesis. The arsenolipids present in Synechocystis sp. PCC 6803 were analysed by high performance liquid chromatography-inductively coupled plasma-mass spectrometry, high performance liquid chromatography-electrospray mass spectrometry, and high resolution tandem mass spectrometry. The two major arsenolipids were characterised as arsenosugar phospholipids based on their assigned molecular formulas C47H88O14AsP and C47H90O14AsP, and tandem mass spectrometric data demonstrated the presence of the phosphate arsenosugar and acylated glycerol groups