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| 1 | Wood density and carbon concentration of coarse woody debris in native forests,Brazil显示文摘Background: With the objective of increasing knowledge on biomass and carbon stocks, and thus improving the accuracy of published estimates, the present study explored wood density and carbon concentration of coarse woody debris (diameter≥10) by decay class in a Seasonal Semi-deciduous Forest (SSF) area in the Atlantic Rain Forest and in a Cerrado sensu-stricto (CSS) area (Brazilian savanna), in Brazil. Two strata were identified in each area and ten sampling units were systematic located in each stratum. Data were collected according to the line intersect sampling method. Each tallied element, the diameter, length, and perpendicular width were recorded at the transect intersection point. Each element was classified into a decay class, and the species was identified when possible. Sample discs were cut from each element, from which cylindrical samples were extracted and oven-dried to determine density. These cylinders were milled and analyzed using a LECO-C632 to determine carbon concentration as percentage of mass. Results: In both areas, wood density decreased as the decay class increased. For SSF the mean carbon concentration of all analyzed samples was 49.8% with a standard deviation of 3.3, with a range of 27.9–57.0% across 506 observations. For CSS the general mean was 49.6% with a standard deviation of 2.6, with a range of 31.2–54.5% over 182 observations. Carbon concentration barely change between decay classes. Carbon stock was estimated at 3.3 and 0.7 MgC/ha for the SSF and the CSS, respectively. Similar results were obtained when using a 50% conversion constant. Conclusions: The present study concludes that wood density decreases as the woody debris becomes more decomposed, a pattern found in many previous studies. The carbon concentration, however, barely changes between decay classes, and that result is consistent with most of the literature reviewed. Our carbon concentrations are very close to the 50% used most commonly as a conversion factor. We strongly recommend that future studies of CWD evaluate wood density and carbon concentration by decay class to address the uncertainty still found in the literature. | Andrea B.Moreira Timothy G.Gregoire Hilton Thadeu Z.do Couto | 2019 | Forest Ecosystems2019，6，2： | 3 |
| 2 | The neurosphere assay:an effective in vitro technique to study neural stem cells显示文摘Neural stem cells(NSCs)are known to be present in the adult mammalian brain where they constitutively differentiate into the neuronal,astroglial,and oligodendroglial lineages,in defined processes termed neurogenesis,ast rogl iogenesis and oligodendrogenesis,respectively(reviewed in Braun and Jessberger,2014).During brain development,NSCs are present throughout the brain,becoming progressively restricted to defined brain regions.In the adult brain,NSCs are mainly present in areas classically known as neurogenic niches,i.e.the subventricular zone(SVZ),along the lateral walls of the lateral ventricles,and the subgranular zone,located in the dentate gyrus(DG)of the hippocampus. | Rita Soares Filipa F.Ribeiro Diogo M.Lourenço Rui S.Rodrigues João B.Moreira Ana M.Sebastião Vanessa A.Morais Sara Xapelli | 2021 | Neural Regeneration Research2021，16，11： | 1 |
| 3 | MicroRNA‐143 reduces viability and increases sensitivity to 5‐fluorouracil in HCT116 human colorectal cancer cells显示文摘 | Pedro M.Borralho Betsy T.Kren Rui E.Castro Isabel B.Moreira da Silva Clifford J.Steer Cecília M. P.Rodrigues | 2009 | FEBS Journal2009，，22： | 1 |
| 4 | NF‐κB and apoptosis in colorectal tumourigenesis显示文摘 | M. M.Aranha P. M.Borralho P.Ravasco I. B.Moreira da Silva L.Correia A.Fernandes M. E.Camilo C. M. P.Rodrigues | 2007 | European Journal of Clinical Investigation2007，，5： | 1 |
| 5 | Effects of lime addition on geotechnical properties of sedimentary soil in Curitiba,Brazil显示文摘The soil of the Guabirotuba geological formation(Paraná Basin, Brazil) has physico-mechanical properties which are not suitable for its utilization in pavement construction, in protection of hillsides and slopes, or as shallow foundation support. Treatment of this soil by lime addition would improve its usability. The present context intends to determine the ratio between the splitting tensile strength(q_t)and the unconfined compressive strength(q_u) of clayey soil in the metropolitan region of Curitiba City,which has been treated with different lime contents and curing times. The control parameters evaluated include lime content(L), curing time(t), moisture content(w), and ratio of porosity to volumetric lime content(η/L_v). It was observed that the q_t/q_u ratio is between 0.17 and 0.2 in relation to the curing time,and an exponential relation exists between them. Meanwhile, the unconfined compressive strength of lime-treated soil was found to be approximately four times the initial value. | Jair A.Baldovino Eclesielter B.Moreira Wagner Teixeira Ronaldo L.S.Izzo Juliana L.Rose | 2018 | Journal of Rock Mechanics and Geotechnical Engineering2018，10，1： | 1 |
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