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1.
We studied 17 pedigrees with 108 affected males with X-linked juvenile retinoschisis (RS; McKusick No. 31270) and have analyzed all of the known polymorphic markers in the RS region of Xp22.1-p22.2 between DXS987 and DXS41. By haplotype analyses we found 7 individuals who showed crossovers in this interval surrounding RS. We previously reported AFM291wf5 as the centromeric boundary, and this remains unchanged in the present study. A new recombination was identified on the telomeric side at (DXS1195, DXS418). Our data support the locus order Xpter--(DXS987, DXS207, DXS1053, DXS43)--(DXS1195, DXS418)--(RS, DXS257, DXS999)--(AFM291wf5, DXS443)--DXS1052--(DXS1226, DXS274, DXS41)--Xcen; loci grouped in parentheses could not be mutually ordered by our genetic data. Physical mapping has indicated a distance of at most 900-1,000 kb between (DXS1195, DXS418) and AFM291wf5. No recombination was observed between RS and DXS257 which lies in our new interval of interest, but one critical individual was not informative with this marker. Our data now define the smallest RS inclusion interval. This interval is contained on a single YAC from which we have identified expressed sequences as candidate genes for RS.  相似文献   
2.
Kinetic studies of swelling of cotton cellulose with 75% (w/w) EDA solution have been carried out. Three rates of the reaction were observed in the temperature range 10–35°C: first, the very fast rate (k1) lasting for about 10 s; second, the extremely slow rate (k2) lasting for 30–50 s; and third, once again a fast rate (k3), k1 being faster than k3. k1 was attributed to the swelling action of EDA–monohydrate in amorphous regions of cellulose; k2 was assigned to the penetration of swelling species into crystallities accompanied by breakage of H bonds in these regions; and k3 was assigned to the opening up of the crystallites. Activation energy values confirmed this trend. At higher temperatures (35–55°C), the middle rate k2 merged with k3, giving only two rates, k1 and k2+3, as the higher temperatures brought about simultaneous diffusion of swelling agent into, and decrystallization of, the crystalline portions of cellulose. EDA solution of 65% (w/w) concentration gave only two rates: the initial fast rate assigned to the swelling of the amorphous portion, followed by a slow one, operating in mesomorphous regions of cellulose, without any appreciable decrystallization. This was atributed to the important fact, viz., the absence of EDA–monohydrates in the solution.  相似文献   
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Nano crystalline Zn-substituted Ni ferrite films with compositions of Ni1?xZnxFe2O4 (x = 0.25, 0.50, 0.75) were synthesized by sol–gel spin coating method. The synthesized films were characterized for their structural, morphology, optical, electric, and magnetic properties using x-ray diffraction, scanning electron microscope, UV-Vis spectrometer, two probe resistivity, and vibrating sample magnetometer techniques, respectively. The corresponding results indicate that zinc content has significant effect on physical, magnetic, and optical properties of the ferrite. X-ray diffraction studies of thin films showed that the samples have pure cubic spinel phase. The crystallite size is of the nanoparticles estimated using Debey-Scherrer’s method was found to be in the range of 10.27 to 14.97 nm. The lattice parameter was found to be increased from 8.35 to 8.40 Å with increasing Zn2+ contents. The morphology of the thin films depicted the formation of well-developed nano-sized clusters with homogeneous and agglomerated. The optical absorption seen to be affected due to the presence of Zn in Ni-Zn ferrite thin films. Ni-Zn ferrite thin films possess small coercivity and remnant magnetization, which indicates the soft magnetic nature of the material. Electrical resistivity of the films decreases with increasing temperature, suggesting the semiconducting nature of the samples.  相似文献   
5.
Nickel oxide (NiO) thin films have been synthesized by simple and inexpensive chemical bath deposition at low temperature. The synthesized thin films were annealed at 623 K and used for further characterization. Structural and morphological properties of the NiO thin film were characterized using X-ray diffraction and scanning electron microscope (SEM), respectively. The structural study shows the simple cubic formation of NiO thin films with average crystallite size of 9 nm. Honeycomb like surface morphology with porous structure was observed from the SEM study. NiO thin film electrode has been used as a counter electrode in dye sensitized solar cell. Finally, photovoltaic parameters such as short circuit current density (Jsc), open circuit voltage (Voc), Fill Factor (FF) and efficiency (η) have been studied.  相似文献   
6.
Nowadays, the web service has become the emerging communication technology where the interaction of each user is performed through the World Wide Web. However, the performance of the web service mechanism is degraded due to security flaws that occur throughout the Internet.. The user or service requester may not attain the relevant web service for their requirement. To overcome this problem, the newly developed multi-objective based Cuckoo Search (MCS) algorithm is proposed in this article. Initially, the input query model was built by the query keyword that is provided by the service requester. Then, the given query is matched with the database that hosts the web services that relates to input query. Among the various services, the user has to select the appropriate web service using the proposed algorithm. The MCS algorithm is newly designed by combining the Cuckoo Search algorithm and the QoS parameter based multiple objectives. Additionally, the new mathematical model of fitness is evaluated by the multi-objective parameters. Finally, the proposed algorithm exploits the fitness value to select the relevant web service for the user query. The experimental results are validated and performance is analyzed by the parameters of precision, recall, and F-measure. Thus, 86.6% of precision value was obtained by the proposed method, which ensured provision of the appropriate web service.  相似文献   
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Nanocomposites of CdS nanocrystals with conducting polyaniline doped with camphor sulfonic acid (CSA) have been prepared by spin coating technique and investigated by X-ray diffraction, field emission scanning electron microscopy (FESEM), fourier transform infra red spectroscopy (FTIR), UV–visible spectroscopy and electrical transport method. The X-ray diffraction patterns showed broad peaks due to formation of nanoparticles of CdS in polyaniline matrix. FESEM showed that the transformation of morphology from agglomeration to nanopetals. The FTIR spectra confirmed the interaction between CSA and polyaniline (PANi)–CdS nanocomposite. The UV–visible spectrums revealed the enhancement of doping level for the PANi–CdS nanocomposites which is assigned to the existence of greater number of charges on the polymer backbone. DC electrical conductivity studies showed an increase in conductivity of PANi–CdS nanocomposites from 6.9?×?10?6 to 3.14?×?10?4 due to addition of CSA (10–50?%).  相似文献   
9.
Nanocomposites are a new class of polymeric materials which include organic or inorganic nano‐phase materials. These nanocomposite films can show interesting properties which have many applications for wavelength conversion and energy saving. In this paper, we present polyolefin based nanocomposite films prepared using wavelength‐converting red ‘phosphors’ such as Y2O3: Eu3+ and LiAl5O8:Fe3+ and blue ‘phosphor’ CaMgSi2O6: Eu2+. The durability of the polymer chain is unaffected by incorporation of inorganic nanoparticles as there is no direct interaction between them. The addition of surfactant in the nanocomposite film helps to improve the dispersion ability of the nanoparticles and increase the flexibility of the polymer film. Wavelength‐converting ‘nanophosphors’ incorporated in a polymer matrix help to increase the tensile strength of the film. The films show excellent wavelength conversion ability of UV light into the visible and near IR range. These nanocomposite films have great application in energy saving devices. Copyright © 2012 Society of Chemical Industry  相似文献   
10.
Here we report a successful preparation of nanostructured calcium silicate by wet chemical approach. The synthesized sample was characterized by various physico-chemical methods. Thermal stability was investigated using thermo-gravimetric and differential thermal analysis (TG-DTA). Structural characterization of the sample was carried out by the X-ray diffraction technique (XRD) which confirmed its single phase hexagonal structure. Transmission electron microscopy (TEM) was used to study the nanostructure of the ceramics while homogeneous grain distribution was revealed by scanning electron microscopy studies (SEM). The elemental analysis data obtained from energy dispersive X-ray spectroscopy (EDAX) were in close agreement with the starting composition used for the synthesis. Superhydrophilic nature of CaSiO3 was investigated at room temperature by sessile drop technique. Effect of porous nanosized CaSiO3 on early adhesion and proliferation of human bone marrow mesenchymal stem cells (BMMSCs) and cord blood mesenchymal stem (CBMSCs) cells was measured in vitro. MTT cytotoxicity test and cell adhesion test showed that the material had good biocompatibility and promoted cell viability and cell proliferation. It has been stated that the cell viability and proliferation are significantly affected by time and concentration of CaSiO3. These findings indicate that the CaSiO3 ceramics has good biocompatibility and that it is promising as a biomaterial.  相似文献   
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