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Phosphorus-doped ZnO films were grown by pulsed laser deposition using a ZnO:P2O5-doped target as the phosphorus source with the aim of producing p-type ZnO material. ZnO:P layers (with phosphorus concentrations of between 0.01 to 1 wt%) were grown on a pure ZnO buffer layer. The electrical properties of the films were characterised from temperature dependent Hall-effect measurements. The samples typically showed weak n-type conduction in the dark, with a resistivity of 70 Ω cm, a Hall mobility of μn0.5 cm2 V −1 s−1 and a carrier concentration of n3×1017 cm−3 at room temperature. After exposure to an incandescent light source, the samples underwent a change in conduction from n- to p-type, with an increase in mobility and decrease in concentration for temperatures below 300 K.  相似文献   
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We show that for below certain critical indices there are functions whose Jacobi or Laguerre expansions have almost everywhere divergent Cesàro and Riesz means of order .

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This paper investigates how three children provided mathematical explanations whilst playing with a set of glass jars in a Swedish preschool. Using the idea of semiotic bundles combined with the work on multimodal interactions, the different semiotic resources used individually and in combinations by the children are described. Given that the children were developing their verbal fluency, it was not surprising to find that they also included physical arrangements of the jars and actions to support their explanations. Hence, to produce their explanations of different attributes such as thin and sameness, the children drew on each other’s gestures and actions with the jars. This research has implications for how the relationship between verbal language and gestures can be viewed in regard to young children’s explanations.  相似文献   
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This abstract presents a model project aimed to train community lay health workers about genetics, increase cultural competency of genetic services providers, and provide local access to genetic services in primarily Hispanic communities in the state of Arizona. Health Start, a community-based prenatal outreach program, served as the basis for providing genetic education and services. A genetics training curriculum was developed and training of community lay health workers was provided. Cultural and Spanish language training was provided for all genetic services providers. Pediatric genetics outreach clinics were established in eight communities. Community-based lay health workers eagerly incorporate genetic information into their public health knowledge base, but this may not lead to acceptance of these personnel by local health care providers as sources of referrals for specialized health services such as genetics. Cultural competence training of genetic service providers is enthusiastically accepted and utilized in the provision of locally accessible genetics clinics.  相似文献   
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We present a localization theorem for expansions in eigenfunctions of the Laplace-Beltrami operator on a compact two-point homogeneous space.  相似文献   
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The crystalline, optical and electrical properties of N-doped ZnO thin films were measured using X-ray diffraction, photoluminescence and Hall effect apparatus, respectively. The samples were grown using pulsed laser deposition on sapphire substrates coated priorly with ZnO buffer layers. For the purpose of acceptor doping, an electron cyclotron resonance (ECR) plasma source operated as a low-energy ion source was used for nitrogen incorporation in the samples. The X-ray diffraction analyses indicated some deterioration of the ZnO thin film with nitrogen incorporation. Temperature-dependent Van der Pauw measurements showed consistent p-type behavior over the measured temperature range of 200–450 K, with typical room temperature hole concentrations and mobilities of 5×1015 cm−3 and 7 cm2/V s, respectively. Low temperature photoluminescence spectra consisted of a broad emission band centered around 3.2 eV. This emission is characterized by the absence of the green deep-defect band and the presence of a band around 3.32 eV.  相似文献   
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[structure: see text] The structure of spirastrellolide A, a novel macrolide isolated from the marine sponge Spirastrella coccinea, has been revised to accommodate new MS and chemical transformation data. Relative configurations of three major fragments of the molecule have been elucidated from ROESY and coupling constant data. Spirastrellolide A has been shown to be a potent and fairly selective inhibitor of protein phosphatase 2A.  相似文献   
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