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1.
The extracellular matrix (ECM) is an important regulator of excitability and synaptic plasticity, especially in its highly condensed form, the perineuronal nets (PNN). In patients with drug-resistant mesial temporal lobe epilepsy (MTLE), hippocampal sclerosis type 1 (HS1) is the most common histopathological finding. This study aimed to evaluate the ECM profile of HS1 in surgically treated drug-resistant patients with MTLE in correlation to clinical findings. Hippocampal sections were immunohistochemically stained for aggrecan, neurocan, versican, chondroitin-sulfate (CS56), fibronectin, Wisteria floribunda agglutinin (WFA), a nuclear neuronal marker (NeuN), parvalbumin (PV), and glial-fibrillary-acidic-protein (GFAP). In HS1, besides the reduced number of neurons and astrogliosis, we found a significantly changed expression pattern of versican, neurocan, aggrecan, WFA-specific glycosylation, and a reduced number of PNNs. Patients with a lower number of epileptic episodes had a less intense diffuse WFA staining in Cornu Ammonis (CA) fields. Our findings suggest that PNN reduction, changed ECM protein, and glycosylation expression pattern in HS1 might be involved in the pathogenesis and persistence of drug-resistant MTLE by contributing to the increase of CA pyramidal neurons’ excitability. This research corroborates the validity of ECM molecules and their modulators as a potential target for the development of new therapeutic approaches to drug-resistant epilepsy.  相似文献   
2.
As technology scales toward deep submicron, the integration of complete system-on-chip (SoC) designs consisting of large number of Intellectual Property (IP) blocks (cores) on the same silicon die is becoming technically feasible. Until recently, the design-space exploration for SoCs has been mainly focused on the computational aspects of the problem. However, as the number of IP blocks on a single chip and their performance continue to increase, a shift from computation-based to communication-based designs becomes mandatory. As a result, the communication architecture plays a major role in the area, performance and energy consumption of the overall systems [Pasricha S, Dutt N. On-chip communication architectures: system on chip interconnect. Amsterdam: Elsevier Inc.; 2008, Kim J, Verbauwhede I, Chang MCF. Design of an interconnect architecture and signaling technology for parallelism in communication. IEEE Trans VLSI Syst 2007;15(8):881-94].This article presents a structure of a wrapper as a component of Code Division Multiple Access, CDMA, based shared bus architecture in a SoC. Two types of wrappers can be identified, master and slave. A master wrapper is located between the arbiter and CDMA coded physical interconnect, while a slave connects the CDMA coded bus with memory/peripheral module. In the proposal, only bus lines that carry address and data signals are CDMA coded. We implemented a pair of master-slave wrapper described in VHDL and confirmed its functionality using testbenches. Also we synthesized wrappers using a Xilinx Spartan and Virtex devices to determine resource requirements in respect to a number of equivalent gates, communication bandwidth, latency and power consumption. Specifically we involved a Design_Quality, DQ, metric for wrapper performance evaluation. A pair of master-slave wrapper seems to occupy appropriate space, in average 2000 equivalent gates, considering CPU cost of about 30,000 gates, what is less than 8% of hardware overhead per CPU. We also present experimental results which show that benefits of involving CDMA coding relates both to decreasing a number of bus lines and accomplishing simultaneous multiple master-slave connections at relatively low-power consumption and high communication bandwidth. Convenient range indices RW and RR to determine data transfer rate for Write and Read operations in multiprocessor bus systems that use TDMA and CDMA data transfer techniques. The obtained results show that increased data transfer latencies involved by CDMA data transfer are compensated by simultaneous master-slave transfers.  相似文献   
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4.
A method for synthesis of digital bandpass and bandstop filters obtained by parallel connection of two allpass networks, is considered. A procedure is based on allpass network linear phase approximation at three levels in mini-max sense, which enables obtaining of selectivedigital filters in form of elliptic filters with linear phase in both passband and stopband.  相似文献   
5.
Columnar liquid crystals confined in cylindrical pores are known to orient perpendicular to the pore axis, although for potential nanoelectronic applications they would need to be aligned axially. The X‐ray diffraction study reveals that while in all three compounds examined, the columns arrange in concentric circles in circular pores, axial alignment is indeed achieved for the hexagonal phase of a discotic hexa‐peri‐hexabenzocoronene in “triangular pores,” and for the square phase of a T‐shaped amphiphile in “square pores.” For the third compound, a carbazole dendron with very soft hexagonal columns, a new three‐circle configuration is observed by atomic force microscopy (AFM) in triangular pores. The complex structure of domain walls in columnar liquid crystals is thus seen for the first time on the level of individual columns. A simple estimation of free energies confirms that it is the distortion of polygonal columnar lattice that prevents axial orientation in circular pores. The model also explains the appearance of the three‐circle arrangement of soft columns.  相似文献   
6.
The outage performance of the amplify‐and‐forward relaying strategies over mutually uncorrelated extended generalized‐K fading channels is addressed in this paper. The attention is dedicated to the analyses of the noise‐limited and also interference‐limited environment. The new analytical expression for outage probability of observed relaying system in the presence of thermal noise is derived using the method for approximating equivalent signal‐to‐noise ratio. In addition, the outage performance is studied for the dual‐hop system when only the single dominant co‐channel interference is inherent at the relay and destination node. The correctness of the proposed mathematical derivations is verified by simulations. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
7.
This article focuses on the electrophoretic co-deposition of SiC and MgO, which has not been previously reported. The EPD of SiC has been widely investigated, whilst the EPD of SiC with sintering additives is usually not taken into account since every compound added to the suspension seriously affects the zeta-potential and the conductivity, the two main parameters that should be optimized to achieve a good deposit. We comprehensively observed the effects of the individual compounds on the colloidal behaviour of a suspension suitable for co-deposition to achieve good homogeneity and the highest possible green density. The obtained green densities reached up to 1.92 g/cm3, which correspond to 60% of theoretical density, whilst after sintering in open air at 1350 °C the densities reached 2.33 g/cm3. SEM and TEM analyses revealed that the microstructure is composed of SiC grains embedded in a SiO2 matrix, whilst XRD confirmed that even though the sintering caused a partial oxidation and the appearance of an amorphous phase, the prevailing crystalline phase is still β-SiC. In the presence of MgO, SiO2 also appears in the crystalline form as cristobalite.  相似文献   
8.
Neural Computing and Applications - Successfully organizing the transport of hazardous materials and handling them correctly is a very important logistical task that affects both the overall flow...  相似文献   
9.
Iridium(III) complexes of the type [Ir(η5‐C5Me5)Cl2{Ph2PCH2CH2CH2S(O)xPh‐κP}] (x=0–2; 1 – 3 ) and [Ir(η5‐C5Me5)Cl{Ph2PCH2CH2CH2S(O)xPh‐κPS}][PF6] (x=0–1; 4 and 5 ) with 3‐(diphenylphosphino)propyl phenyl sulfide, sulfoxide, and sulfone ligands Ph2PCH2CH2CH2S(O)xPh were designed, synthesized, and characterized fully, including X‐ray diffraction analyses for complexes 3 and 4 . In vitro studies against human thyroid carcinoma (8505C), submandibular carcinoma (A253), breast adenocarcinoma (MCF‐7), colon adenocarcinoma (SW480), and melanoma (518A2) cell lines provided evidence for the high biological potential of the neutral and cationic iridium(III) complexes. Neutral iridium(III) complex 5 proved to be the most active, with IC50 values up to about 0.1 μM , representing activities of up to one order of magnitude higher than cisplatin. Using 8505C cells, apoptosis was shown to be the main mechanism through which complex 5 exerts its tumoricidal action. The described iridium(III) complexes represent potential leads in the search for novel metal‐based anticancer agents.  相似文献   
10.
Dehydrated MCM-41 (S1) was functionalized under nitrogen with 3-chloropropyltriethoxysilane (CPTS) and 3-aminopropyltriethoxysilane (APTS) by grafting in toluene at 80 °C over 48 h to give the corresponding materials S2 and S3, respectively. Subsequently, S2 and S3 were suspended in methanol and reacted in a nitrogen atmosphere with betulinic acid (BA) for 48 h at 65 °C (in the presence of the triethylamine of S2) to give the BA-functionalized materials S4 and S5. All materials studied were characterized by powder X-ray diffraction, X-ray fluorescence, nitrogen gas sorption, multinuclear MAS NMR spectroscopy, thermogravimetry, UV spectroscopy, IR, SEM, and TEM. To study the release of BA, S4 and S5 were suspended in solutions simulating various body pH conditions (pH 7.4, 5.5, and 3.0). Results of the quantification of BA release by HPLC for S4 show a pH-dependent and very slow BA release following a logarithmic tendency, while S5 behaves differently, also pH-dependent but, in this case, fast release of BA which requires only days for total release of the therapeutic compound. In addition, the cytotoxic activity of all synthesized materials against various cancer cell lines was studied. The results show the absence of an antiproliferative effect on the surfaces without BA S1-S3, while an antiproliferative effect was observed with S4 and S5 and was attributed to the release of BA in the medium.  相似文献   
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