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  1. Elevated CO2 alters anatomy, physiology, growth, and reproduction of red mangrove (Rhizophora mangle L.)
    Farnsworth EJ, Ellison AM, Gong WK
    Oecologia, 1996 Dec;108(4):599-609.
    PMID: 28307791 DOI: 10.1007/BF00329032
    Mangroves, woody halophytes restricted to protected tropical coasts, form some of the most productive ecosystems in the world, but their capacity to act as a carbon source or sink under climate change is unknown. Their ability to adjust growth or to function as potential carbon sinks under conditions of rising atmospheric CO2 during global change may affect global carbon cycling, but as yet has not been investigated experimentally. Halophyte responses to CO2 doubling may be constrained by the need to use carbon conservatively under water-limited conditions, but data are lacking to issue general predictions. We describe the growth, architecture, biomass allocation, anatomy, and photosynthetic physiology of the predominant neotropical mangrove tree, Rhizophora mangle L., grown solitarily in ambient (350 μll(-1)) and double-ambient (700 μll(-1)) CO2 concentrations for over 1 year. Mangrove seedlings exhibited significantly increased biomass, total stem length, branching activity, and total leaf area in elevated CO2. Enhanced total plant biomass under high CO2 was associated with higher root:shoot ratios, relative growth rates, and net assimilation rates, but few allometric shifts were attributable to CO2 treatment independent of plant size. Maximal photosynthetic rates were enhanced among high-CO2 plants while stomatal conductances were lower, but the magnitude of the treatment difference declined over time, and high-CO2 seedlings showed a lower Pmax at 700 μll(-1) CO2 than low-CO2 plants transferred to 700 μll(-1) CO2: possible evidence of downregulation. The relative thicknesses of leaf cell layers were not affected by treatment. Stomatal density decreased as epidermal cells enlarged in elevated CO2. Foliar chlorophyll, nitrogen, and sodium concentrations were lower in high CO2. Mangroves grown in high CO2 were reproductive after only 1 year of growth (fully 2 years before they typically reproduce in the field), produced aerial roots, and showed extensive lignification of the main stem; hence, elevated CO2 appeared to accelerate maturation as well as growth. Data from this long-term study suggest that certain mangrove growth characters will change flexibly as atmospheric CO2 increases, and accord with responses previously shown in Rhizophora apiculata. Such results must be integrated with data from sea-level rise studies to yield predictions of mangrove performance under changing climate.
  2. Meroterpenes with toll-like receptor 3 regulating activity from the endophytic fungus Guignardia mangiferae
    Han WB, Dou H, Yuan WH, Gong W, Hou YY, Ng SW, et al.
    Planta Med, 2015 Jan;81(2):145-51.
    PMID: 25519918 DOI: 10.1055/s-0034-1383392
    The endophytic fungus Guignardia mangiferae isolated from Ilex cornuta leaves was shown to produce a family of meroterpenes with toll-like receptor 3 regulating activity (1-9), of which 1-3 possessed new structures. The absolute stereochemistry of 1-3 was assigned through a combination of nuclear magnetic resonance experiments, chemical derivation, CD spectra, and single-crystal X-ray diffraction analyses (CuK α ). The precursor labeled cultivation suggests that these meroterpenes are most likely assembled through terpenoid-shikimate pathways. Moreover, meroterpenes 1-3, 5-7, and 9 selectively upregulate, but 4 and 8 downregulate the toll-like receptor 3 expression in mouse dendritic cells at 10.0 µM.
  3. Expanding Access: Cost-effectiveness of Cochlear Implantation and Deaf Education in Asia
    Emmett SD, Sudoko CK, Tucci DL, Gong W, Saunders JE, Global HEAR (Hearing Loss Evaluation, Advocacy, and Research) Collaborative:, et al.
    Otolaryngol Head Neck Surg, 2019 10;161(4):672-682.
    PMID: 31210566 DOI: 10.1177/0194599819849917
    OBJECTIVE: To determine the cost-effectiveness of cochlear implantation (CI) with mainstream education and deaf education with sign language for treatment of children with profound sensorineural hearing loss in low- and lower-middle income countries in Asia.

    STUDY DESIGN: Cost-effectiveness analysis.

    SETTING: Bangladesh, Cambodia, India, Indonesia, Nepal, Pakistan, Philippines, and Sri Lanka participated in the study.

    SUBJECTS AND METHODS: Costs were obtained from experts in each country with known costs and published data, with estimation when necessary. A disability-adjusted life-years model was applied with 3% discounting and 10-year length of analysis. A sensitivity analysis was performed to evaluate the effect of device cost, professional salaries, annual number of implants, and probability of device failure. Cost-effectiveness was determined with the World Health Organization standard of cost-effectiveness ratio per gross domestic product (CER/GDP) per capita <3.

    RESULTS: Deaf education was cost-effective in all countries except Nepal (CER/GDP, 3.59). CI was cost-effective in all countries except Nepal (CER/GDP, 6.38) and Pakistan (CER/GDP, 3.14)-the latter of which reached borderline cost-effectiveness in the sensitivity analysis (minimum, maximum: 2.94, 3.39).

    CONCLUSION: Deaf education and CI are largely cost-effective in participating Asian countries. Variation in CI maintenance and education-related costs may contribute to the range of cost-effectiveness ratios observed in this study.

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