431 research outputs found
Modulation of Adult Neurogenesis in the Olfactory Bulb in an Acute Mouse Model of ParkinsonĀ“s Disease
Hyposmia, often preceding the cardinal motor symptoms, such as bradykinesia, rigidity, tremor at rest and postural instability, is frequently reported in PD. This symptom appears to be related to an increased number of dopamine neurons in the periglomerular layer (PGL) of the OB. In the histological study, we have investigated the survival and neuronal differentiation of NPC in the OB, following L-DOPA and/or Selegiline in a unilateral, intranigral 6-OHDA lesion model in mice. Our data show that the number of NPC in the SVZ is decreased after 6-OHDA lesion, while there is no difference from control in lesioned mice with Selegiline or L-DOPA treatment. Moreover, the monoamine oxidase-B inhibitor, Selegiline, is able to normalize the number of dopamine neurons by increasing the number of TUNEL+ cell and reverses the dopaminergic differentiation to control in the PGL, while L-DOPA treatment sustains the increased number, by increasing the survival of NPC and upregulating 2-fold dopaminergic differentiation observed in 6-OHDA lesioned animals. In the behavioral study, to understand the olfactory function after 6-OHDA lesion and the effects of Selegiline treatment, six different experimental groups were investigated and performed an olfactory discrimination test. The data show that a delayed olfactory deficit was first appeared 12 weeks post 6-OHDA lesion and the recovery of olfactory function followed a daily, chronic treatment of Selegiline for additional 12 weeks. However, the olfactory dysfunction of the animals relapses again after a 4-week withdrawal of Selegiline treatment.
To combine the findings of our studies, we conclude that there is a distinct modulation of newly generated dopamine neurons of the OB after L-DOPA and/or Selegiline treatment. Furthermore, a delayed olfactory deficit was detected after a downregulation of adult neurogenesis, and only a chronic, continuous treatment of Selegiline can reverse the olfactory dysfunction in an acute mouse model of PD.
Our findings provide practical implications and stimulate further clinical and preclinical research, bridging the basic knowledge of hyposmia of PD from bench to bedside. Although the relationship of hyposmia and an increased number of dopamine neurons in the OB of PD patients is not well defined yet, the evidence in this study may offer the explanation, that the dysregulation of adult neurogenesis might be one of reasons to cause hyposmia of PD. Moreover, the effects of Selegiline on olfactory function could be a consideration for clinical application. However, further studies are needed to show whether the interaction of dopamine depletion and drug treatment plays a role in olfactory function in PD patients
Transactive Energy and Flexibility Provision in Multi-microgrids using Stackelberg Game
Aggregating the demand side flexibility is essential to complementing the inflexible and variable renewable energy supply in achieving low carbon energy systems. Sources of demand side flexibility, e.g., dispatchable generators, storages, and flexible loads, can be structured in a form of microgrids and collectively provided to utility grids through transactive energy in local energy markets. This paper proposes a framework of local energy markets to manage the transactive energy and facilitate the flexibility provision. The distribution system operator aims to achieve local energy balance by scheduling the operation of multi-microgrids and determining the imbalance prices. Multiple microgrid traders aim to maximise profits for their prosumers through dispatching flexibility sources and participating in localised energy trading. The decision making and interactions between a distribution system operator and multiple microgrid traders are formulated as the Stackelberg game-theoretic problem. Case studies using the IEEE 69-bus distribution system demonstrate the effectiveness of the developed model in terms of facilitating the local energy balance and reducing the dependency on the utility grids
The relationship between velocity utilization rate and pole vault performance
In the pole vault event, the velocity of approach is a highly vital factor. As velocity of approach improvements highly impact performance improvements. This study analysed the relationships between sprint runningās speed (SR), pole running (PR, without jump), and the pole vault approach (PVA, with real jump). Analysed too were the relationships between both the approach and performanceās respective running distance, velocity, and velocity utilization rates. Methods: Ten male pole vaulters were recruited. Measured was each 5-meter segmentās average velocity of his respective SR, PR, and PVA, along with the distance to maximum velocity. Results: The maximum average velocity of the PRās 5m segments altogether was significantly positively correlated with pole vault (PV) performance; The maximum average velocity of the PRās 5m segments altogether was significantly positively correlated with the last 5m PVA average velocity; The PVA velocityās utilization rate was significantly negatively correlated with the difference between the distance to the PRās maximum velocity and the PVAās distance. Conclusion: The PR segmentās maximum speed capability can evaluate both a pole vaulterās potential and pole vault-specific abilities. This studyās recruited pole vaultersā respective approach distances were generally insufficient that resulted in a lower velocity utilization rate. Suggested is that in training, the pole vaulter could first find the distance required to reach the highest velocity upon starting from the PR test. Thus, this subsequently known distance could be applied in tandem with the pole vaultās approach to both improve the PVAās utilization rate and reach the individual highest speed level
Single-crystalline Ī“-Ni2Si nanowires with excellent physical properties
[[abstract]]In this article, we report the synthesis of single-crystalline nickel silicide nanowires (NWs) via chemical vapor deposition method using NiCl2Ā·6H2O as a single-source precursor. Various morphologies of Ī“-Ni2Si NWs were successfully acquired by controlling the growth conditions. The growth mechanism of the Ī“-Ni2Si NWs was thoroughly discussed and identified with microscopy studies. Field emission measurements show a low turn-on field (4.12 V/Ī¼m), and magnetic property measurements show a classic ferromagnetic characteristic, which demonstrates promising potential applications for field emitters, magnetic storage, and biological cell separation.[[notice]]č£ę£å®ē¢[[incitationindex]]SCI[[booktype]]é»åē[[booktype]]ē“
DEVELOPMENT AND VALIDATION OF THE TAIWAN CHILDRENāS ENVIRONMENTAL ACTION INDEX
In this study, we use Smith-Sebasto & Fortnerās (1994) Environmental Action Internal Control Index (EAICI) as a framework to develop, and validate a useful instrument for assessing environmental attitudes and behavior among elementary and middle school children within the Taiwanese context. We dub the new instrument the Taiwan Childrenās Environmental Action Index (TCEAI). Our findings suggest that the TCEAI displays substantial internal consistency (Cronbach's alpha=.92), moderately positive correlations with self-report measures of environmentally responsible behavior (R = .35 to .46, p < .01), and few threats to validity by age or gender. The results suggest that the TCEAI may be used to elicit important dimensions of environmental attitudes and to predict environmentally responsible behavior for elementary and middle school children in Taiwan. Practical implications are discussed
Epigallocatechin-3-gallate-mediated cardioprotection by Akt/GSK-3Ī²/caveolin signalling in H9c2 rat cardiomyoblasts
Background: Epigallocatechin-3-gallate (EGCg) with its potent anti-oxidative capabilities is known for its beneficialeffects ameliorating oxidative injury to cardiac cells. Although studies have provided convincing evidence tosupport the cardioprotective effects of EGCg, it remains unclear whether EGCg affect trans-membrane signalling incardiac cells. Here, we have demonstrated the potential mechanism for cardioprotection of EGCg againstH2O2-induced oxidative stress in H9c2 cardiomyoblasts.Results: Exposing H9c2 cells to H2O2 suppressed cell viability and altered the expression of adherens and gapjunction proteins with increased levels of intracellular reactive oxygen species and cytosolic Ca2+. These detrimentaleffects were attenuated by pre-treating cells with EGCg for 30 min. EGCg also attenuated H2O2-mediated cell cyclearrest at the G1-S phase through the glycogen synthase kinase-3Ī² (GSK-3Ī²)/Ī²-catenin/cyclin D1 signalling pathway.To determine how EGCg targets H9c2 cells, enhanced green fluorescence protein (EGFP) was ectopically expressedin these cells. EGFP-emission fluorescence spectroscopy revealed that EGCg induced dose-dependent fluorescencechanges in EGFP expressing cells, suggesting that EGCg signalling events might trigger proximity changes of EGFPexpressed in these cells.Proteomics studies showed that EGFP formed complexes with the 67 kD laminin receptor, caveolin-1 and -3,Ī²-actin, myosin 9, vimentin in EGFP expressing cells. Using in vitro oxidative stress and in vivo myocardial ischemiamodels, we also demonstrated the involvement of caveolin in EGCg-mediated cardioprotection. In addition,EGCg-mediated caveolin-1 activation was found to be modulated by Akt/GSK-3Ī² signalling in H2O2-induced H9c2cell injury.Conclusions: Our data suggest that caveolin serves as a membrane raft that may help mediate cardioprotectiveEGCg transmembrane signalling
Oxidized-monolayer Tunneling Barrier for Strong Fermi-level Depinning in Layered InSe Transistors
In 2D-semiconductor-based field-effect transistors and optoelectronic
devices, metal-semiconductor junctions are one of the crucial factors
determining device performance. The Fermi-level (FL) pinning effect, which
commonly caused by interfacial gap states, severely limits the tunability of
junction characteristics, including barrier height and contact resistance. A
tunneling contact scheme has been suggested to address the FL pinning issue in
metal-2D-semiconductor junctions, whereas the experimental realization is still
elusive. Here, we show that an oxidized-monolayer-enabled tunneling barrier can
realize a pronounced FL depinning in indium selenide (InSe) transistors,
exhibiting a large pinning factor of 0.5 and a highly modulated Schottky
barrier height. The FL depinning can be attributed to the suppression of metal-
and disorder-induced gap states as a result of the high-quality tunneling
contacts. Structural characterizations indicate uniform and atomically thin
surface oxidation layer inherent from nature of van der Waals materials and
atomically sharp oxide-2D-semiconductor interfaces. Moreover, by effectively
lowering the Schottky barrier height, we achieve an electron mobility of 2160
cm/Vs and a contact barrier of 65 meV in two-terminal InSe transistors. The
realization of strong FL depinning in high-mobility InSe transistors with the
oxidized monolayer presents a viable strategy to exploit layered semiconductors
in contact engineering for advanced electronics and optoelectronics
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