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39 research outputs found

Germination and seedling establishment in cashew (Anacardium occidentale L.): An interaction between seed size, relative growth rate and seedling biomass

Author: M.G. Nayak and G.S. Mohana Babli Mog, J.D. Adiga
Publication venue: 'Scienceflora Publishers Pvt. Ltd.'
Publication date: 21/09/2017
Field of study

Seeds of cashew were used to determine the effect of seed mass (5.2 to 7.8 g) on germination, seedling emergence and growthunder nursery conditions. Germination percentage and germination time showed significant correlation with seed mass. Largesized seeds had higher germination percentage (81.6%) and produced more vigorous seedlings. Per cent seedling emergence wasrelated to seed mass with large sized seeds exhibited faster emergence. Seed mass significantly affected seedling survival andsurvival rate was high in seedlings arising from large sized seeds (62.9%). Seedling vigor expressed in terms of shoot and rootlength, leaf number, leaf area and total dry matter was significantly affected by seed mass. Seedlings that emerged from large sizedseeds showed better growth and produced heavier seedlings as compared to medium sized seeds. RGR showed significant variation(0.152 to 0.240 g g-1day-1) among two seed size classes positively correlated with seed mass, leaf area (LA), unit leaf rate per unitleaf area (ULRM), root to shoot ratio (R/S) and root mass ratio (RMR) and negatively with stem mass ratio (SMR). The studyconcluded that the seed mass and RGR have influence on seedling growth and success of seedling establishment in cashew

Update Publishing (E-Journals)

Impact of SARS-CoV-2 vaccination of children ages 5–11 years on COVID-19 disease burden and resilience to new variants in the United States, November 2021–March 2022: A multi-model study

Background: The COVID-19 Scenario Modeling Hub convened nine modeling teams to project the impact of expanding SARS-CoV-2 vaccination to children aged 5–11 years on COVID-19 burden and resilience against variant strains. Methods: Teams contributed state- and national-level weekly projections of cases, hospitalizations, and deaths in the United States from September 12, 2021 to March 12, 2022. Four scenarios covered all combinations of 1) vaccination (or not) of children aged 5–11 years (starting November 1, 2021), and 2) emergence (or not) of a variant more transmissible than the Delta variant (emerging November 15, 2021). Individual team projections were linearly pooled. The effect of childhood vaccination on overall and age-specific outcomes was estimated using meta-analyses. Findings: Assuming that a new variant would not emerge, all-age COVID-19 outcomes were projected to decrease nationally through mid-March 2022. In this setting, vaccination of children 5–11 years old was associated with reductions in projections for all-age cumulative cases (7.2%, mean incidence ratio [IR] 0.928, 95% confidence interval [CI] 0.880–0.977), hospitalizations (8.7%, mean IR 0.913, 95% CI 0.834–0.992), and deaths (9.2%, mean IR 0.908, 95% CI 0.797–1.020) compared with scenarios without childhood vaccination. Vaccine benefits increased for scenarios including a hypothesized more transmissible variant, assuming similar vaccine effectiveness. Projected relative reductions in cumulative outcomes were larger for children than for the entire population. State-level variation was observed. Interpretation: Given the scenario assumptions (defined before the emergence of Omicron), expanding vaccination to children 5–11 years old would provide measurable direct benefits, as well as indirect benefits to the all-age U.S. population, including resilience to more transmissible variants. Funding: Various (see acknowledgments)

Carolina Digital Repository

Evaluation of the US COVID-19 Scenario Modeling Hub for informing pandemic response under uncertainty

Author: Adiga A.
Ben Toh K.
Bents S.
Bhattacharya P.
Bi K.
Biggerstaff M.
Borchering R.K.
Bouchnita A.
Cadwell B.L.
Cavany S.
Chen J.
Chen S.
Chinazzi M.
Contamin L.
Davis J.T.
España G.
Espino J.
Fox S.J.
Galanti M.
Healy J.M.
Hill A.
Hladish T.
Hochheiser H.
Hoops S.
Howerton E.
Hulse J.D.
Hurt B.
Ivy J.S.
Janies D.
Johansson M.A.
Jung S.-M.
Kaminsky J.
Karlen D.
Kerr J.
Kinsey M.
Klahn B.
Lachmann M.
Lee E.C.
Lemaitre J.C.
Lessler J.
Levander J.
Lewis B.
Longini I. Jr.
Loo S.L.
Machi D.
Marathe M.
Mayorga M.E.
McKee C.D.
Meyers L.A.
Moore S.
Mortveit H.
Mu K.
Mullany L.C.
Outten J.
Pastore y Piontti A.
Paul R.
Pei S.
Perkins A.
Pillai A.
Porebski P.
Qin M.
Rainwater-Lovett K.
Reich N.G.
Rosenstrom E.T.
Runge M.C.
Shaman J.
Shea K.
Shin L.
Slayton R.B.
Smith C.P.
Srivastava A.
Swann J.L.
Tallaksen K.
Thill J.-C.
Truelove S.
van Panhuis W.G.
Venkatramanan S.
Vespignani A.
Viboud C.
Wilson A.
Wilson S.
Xiong X.
Yamana T.
Publication venue: Nature Research
Publication date: 01/01/2023
Field of study

Our ability to forecast epidemics far into the future is constrained by the many complexities of disease systems. Realistic longer-term projections may, however, be possible under well-defined scenarios that specify the future state of critical epidemic drivers. Since December 2020, the U.S. COVID-19 Scenario Modeling Hub (SMH) has convened multiple modeling teams to make months ahead projections of SARS-CoV-2 burden, totaling nearly 1.8 million national and state-level projections. Here, we find SMH performance varied widely as a function of both scenario validity and model calibration. We show scenarios remained close to reality for 22 weeks on average before the arrival of unanticipated SARS-CoV-2 variants invalidated key assumptions. An ensemble of participating models that preserved variation between models (using the linear opinion pool method) was consistently more reliable than any single model in periods of valid scenario assumptions, while projection interval coverage was near target levels. SMH projections were used to guide pandemic response, illustrating the value of collaborative hubs for longer-term scenario projections

Carolina Digital Repository