126 research outputs found

    Synthesis of agglomerate-free YAG: Ce3+ phosphors by co-precipitation and low temperature spray pyrolysis

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    Conference Name:2011 International Symposium on Advanced Packaging Materials, APM 2011. Conference Address: Xiamen, China. Time:October 25, 2011 - October 28, 2011.Y3-xCexAl5O12 (YAG: Ce 3+) phosphor particles were prepared by a new method called co-precipitation and low temperature spray pyrolysis (CP-LTSP) with oxalic acid and ammonia as precipitant. It corresponds to the first-step chemical liquid reaction, the second step dehydration and partial decomposition of precipitation droplets at 250°C and then heating at 1100°C or above. Spherical as-prepared particles and agglomerate-free YAG: Ce3+ phosphor particles were obtained respectively. Pure YAG phase could be formed after LTSP at 250°C and then annealing at 1100°C for 4 h. The emission spectra and XRD patterns of YAG: Ce3+ phosphor particles indicated that the optimum doping concentration of Ce3+ was 0.06. The emission intensity increased with the increase of annealing temperature. As a result, the YAG: Ce3+ phosphor particles without optimization annealed at 1550°C for 4 h had the similar emission intensity (96%) of the commercial phosphor by the solid-state method. ? 2011 IEEE

    Peran Daya Dukung Wilayah Terhadap Pengembangan USAha Peternakan Sapi Madura

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    Research conducted on the island of Madura. The aim of the research was analyzed the area-based development of beef cattle in Madura island. Primary research data was sourced from statistics in the Madura district in figures. Data was analyzed using Location Quotient (LQ) method. Data procesing conducted whith spreadsheet from Excel on Microsoft Windows 7. The results showed that the basis for the development of Madura cattle each regency were Pamekasan (sub-district Larangan, Pasean, Batumamar, Palengan, Proppo, Tlanakan, and Pegantenan), Sumenep (sub-district Gayam, Nonggunong and Batuputih), Bangkalan (subdistrict Kokop, Geger, Galis, Tanah Merah, and Blega) and Bangkalan (sub-district Ketapang, Sokobanah, Kedungdung, Sampang, Banyuates, Robatal, and Omben. Conclusion of the research was the development of Madura cattle concentrated in the base region of Madura cattle

    Nodular and diffuse spindle cell infiltration in keloidal scleroderma: a case report

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    Keloidal scleroderma is a variant of scleroderma that presents as firm keloidal nodules or plaques. Due to the similarity in morphology and pathology, it is often distinguished from a hypertrophic scar or keloid. We report a case of keloidal scleroderma with rare nodular and diffuse spindle cell infiltration in histopathology. Recognition of this unusual histopathological feature may help clinicians improve their knowledge and avoid misdiagnosis

    One-pot Synthesis of Lactams Using Domino Reactions: Combination of Schmidt Reaction with Sakuri and Aldol Reaction

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    A series of domino reactions in which the intramolecular Schmidt reaction is combined with either a Sakurai reaction, an aldol reaction, or both is reported. The Sakurai reaction of an allylsilane with an azido-containing enone under Lewis acidic conditions followed by protonation of the resulting titanium enolate species allowed for a subsequent intramolecular Schmidt reaction. Alternatively, the intermediate titanium enolate could undergo an aldol reaction, followed by the intramolecular Schmidt reaction to form lactam products with multiple stereogenic centers. The stereochemical features of the titanium enolate aldol reaction with several 3-azidoaldehyde substrates during this domino process is discussed

    The role of aryl hydrocarbon receptor in vitiligo: a review

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    Vitiligo is an acquired autoimmune dermatosis characterized by patchy skin depigmentation, causing significant psychological distress to the patients. Genetic susceptibility, environmental triggers, oxidative stress, and autoimmunity contribute to melanocyte destruction in vitiligo. Due to the diversity and complexity of pathogenesis, the combination of inhibiting melanocyte destruction and stimulating melanogenesis gives the best results in treating vitiligo. The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that can regulate the expression of various downstream genes and play roles in cell differentiation, immune response, and physiological homeostasis maintenance. Recent studies suggested that AhR signaling pathway was downregulated in vitiligo. Activation of AhR pathway helps to activate antioxidant pathways, inhibit abnormal immunity response, and upregulate the melanogenesis gene, thereby protecting melanocytes from oxidative stress damage, controlling disease progression, and promoting lesion repigmentation. Here, we review the relevant literature and summarize the possible roles of the AhR signaling pathway in vitiligo pathogenesis and treatment, to further understand the links between the AhR and vitiligo, and provide new potential therapeutic strategies

    Deficiency in Silicon Transporter Lsi1 Compromises Inducibility of Anti-herbivore Defense in Rice Plants

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    Silicon (Si) application can significantly enhance rice resistance against herbivorous insects. However, the underlying mechanism is elusive. In this study, silicon transporter mutant OsLsi1 and corresponding wild-type rice (WT) were treated with and without Si to determine Si effects on rice resistance to leaffolder (LF), Cnaphalocrocis medinalis (Guenée) (Lepidoptera: Pyralidae). Si application on WT plants significantly promoted rice plant growth, upregulated expression level of OsLsi1 and increased Si accumulation in the leaves and roots, as well as effectively reduced LF weight gain, while it showed only marginal or no effect on the mutant plants. Furthermore, upon LF infestation, transcript levels of OsLOX, OsAOS2, OsCOI1a, OsCOI1b, and OsBBPI, and activity of catalase, superoxide dismutase, peroxidase, and polyphenol oxidase were significantly higher in Si-treated than untreated WT plants. However, OsLsi1 mutant plants displayed higher susceptibility to LF, and minimal response of defense-related enzymes and jasmonate dependent genes to Si application. These results suggest that induced defense plays a vital role in Si-enhanced resistance and deficiency in silicon transporter Lsi1 compromises inducibility of anti-herbivore defense in rice plants

    Aboveground herbivory does not affect mycorrhiza-dependent nitrogen acquisition from soil but inhibits mycorrhizal network-mediated nitrogen interplant transfer in maize

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    Arbuscular mycorrhizal fungi (AMF) are considered biofertilizers for sustainable agriculture due to their ability to facilitate plant uptake of important mineral elements, such as nitrogen (N). However, plant mycorrhiza-dependent N uptake and interplant transfer may be highly context-dependent, and whether it is affected by aboveground herbivory remains largely unknown. Here, we used 15N labeling and tracking to examine the effect of aboveground insect herbivory by Spodoptera frugiperda on mycorrhiza-dependent N uptake in maize (Zea mays L.). To minimize consumption differences and 15N loss due to insect chewing, insect herbivory was simulated by mechanical wounding and oral secretion of S. frugiperda larvae. Inoculation with Rhizophagus irregularis (Rir) significantly improved maize growth, and N/P uptake. The 15N labeling experiment showed that maize plants absorbed N from soils via the extraradical mycelium of mycorrhizal fungi and from neighboring plants transferred by common mycorrhizal networks (CMNs). Simulated aboveground leaf herbivory did not affect mycorrhiza-mediated N acquisition from soil. However, CMN-mediated N transfer from neighboring plants was blocked by leaf simulated herbivory. Our findings suggest that aboveground herbivory inhibits CMN-mediated N transfer between plants but does not affect N acquisition from soil solutions via extraradical mycorrhizal mycelium

    A novel red phosphor NaLa4(SiO4)(3)F Eu3+

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    通讯作者地址: Feng, G (通讯作者), Xiamen Univ, Dept Mat Sci & Engn, Xiamen 361005, Peoples R China 地址: 1. Xiamen Univ, Dept Mat Sci & Engn, Xiamen 361005, Peoples R China 2. Jingdezhen Ceram Inst, Sch Mat Sci & Engn, Jingdezhen 333001, Peoples R ChinaA novel red phosphor NaLa4(SiO4)(3)F Eu3+ was synthesized by the conventional solid-state reaction at 950 C for the first time The luminescence properties of NaLa4(SiO4)(3)F Eu3+ were investigated and the critical concentration of the activator concentration (Eu3+) was found to be 0 1 mol per formula unit The phosphor presented red luminescence under the ultraviolet excitation of 254 or 395 nm attributed to the transitions from D-5(0) excited states to F-7(J) (J=0-4) ground states of Eu3+ ions The results indicated that this newly developed phosphor could find applications in tricolor fluorescent lamp phosphor-liquid crystal displays and white lighting devices utilizing GaN-based excitation in the near UV (C) 2010 Elsevier BV All rights reserve
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