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Zircons, isotope ratios and element analyses from tonalite and oxide gabbro of the mid-ocean ridge from ODP Hole 176-735BA limiting factor in the accuracy and precision of U/Pb zircon dates is accurate correction for initial disequilibrium in the 238U and 235U decay chains. The longest-lived-and therefore most abundant-intermediate daughter product in the 235U isotopic decay chain is 231Pa (T1/2 = 32.71 ka), and the partitioning behavior of Pa in zircon is not well constrained. Here we report high-precision thermal ionization mass spectrometry (TIMS) U-Pb zircon data from two samples from Ocean Drilling Program (ODP) Hole 735B, which show evidence for incorporation of excess 231Pa during zircon crystallization. The most precise analyses from the two samples have consistent Th-corrected 206Pb/238U dates with weighted means of 11.9325 ± 0.0039 Ma (n = 9) and 11.920 ± 0.011 Ma (n = 4), but distinctly older 207Pb/235U dates that vary from 12.330 ± 0.048 Ma to 12.140 ± 0.044 Ma and 12.03 ± 0.24 to 12.40 ± 0.27 Ma, respectively. If the excess 207Pb is due to variable initial excess 231Pa, calculated initial (231Pa)/(235U) activity ratios for the two samples range from 5.6 ± 1.0 to 9.6 ± 1.1 and 3.5 ± 5.2 to 11.4 ± 5.8. The data from the more precisely dated sample yields estimated DPazircon/DUzircon from 2.2-3.8 and 5.6-9.6, assuming (231Pa)/(235U) of the melt equal to the global average of recently erupted mid-ocean ridge basaltic glasses or secular equilibrium, respectively. High precision ID-TIMS analyses from nine additional samples from Hole 735B and nearby Hole 1105A suggest similar partitioning. The lower range of DPazircon/DUzircon is consistent with ion microprobe measurements of 231Pa in zircons from Holocene and Pleistocene rhyolitic eruptions (Schmitt (2007; doi:10.2138/am.2007.2449) and Schmitt (2011; doi:10.1146/annurev-earth-040610-133330)). The data suggest that 231Pa is preferentially incorporated during zircon crystallization over a range of magmatic compositions, and excess initial 231Pa may be more common in zircons than acknowledged. The degree of initial disequilibrium in the 235U decay chain suggested by the data from this study, and other recent high precision datasets, leads to resolvable discordance in high precision dates of Cenozoic to Mesozoic zircons. Minor discordance in zircons of this age may therefore reflect initial excess 231Pa and does not require either inheritance or Pb loss.
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Madagascar Public Expenditure Review 2015Management of the primary education
 system in Madagascar follows a centralized model, supported
 by de-concentrated services. Education is divided into (a)
 preschool, (b) 5 years of primary education, (c) 4 years of
 lower secondary, (d) 3 years of upper secondary, and (e)
 higher education. An important feature of the Malagasy
 education system is the relatively well developed framework
 for school-based management. The school management
 committees (FAFs, Fiaraha-miombon’Antoka ho amin’ny
 Fampandrosoana ny sekoly) consist of parents, teachers, the
 school director, and representatives from the local
 community. They have been in existence in each school since
 2002, when the government started providing annual grants to
 schools on a per capita basis to cover part of schools’
 operating expenses. The FAFs are responsible for managing
 these grants, and play a critical role in improving
 accountability of service delivery and promoting community
 engagement and social dialogue among local stakeholders. The
 FAFs are also increasingly participating in the financing of
 school operations, including hiring and paying community
 teachers and financing basic supplies. Trends in
 contributions from school committees in the financing of
 education are examined in details later in the paper.
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Paleo-Productivity reconstruction based on Ba content in marine sedimentsProductivity changes in the tropical-subtropical East-Atlantic are reconstructed using a multiproxy approach. This involves comparing the barium content of the marine surface sediment and sediment core records with other export productivity proxies. Recent biogenic barium accumulation rates (Babio-AR) are shown to generally reflect export productivity (Pexp) in the modern East Atlantic. This relationship may also depend on the planktonic ecology of the surface water, which is dominated by the Ba-rich skeletons (celestite of acantharians) in the open marine environment. Coastal and open marine transfer functions are derived by calibrating Babio-AR with export productivity. However, the sedimentary Ba signal is found to decrease with depth below 1850 m, probably due to increased dissolution. Results also show that Ba preservation is not dependent on the amount of fine fraction (< 2µm). lt remains uncertain whether increased silica dissolution through open marine aeolian Fe-input (Bishop, 1988; Takeda, 1998) favours a decreased Ba-flux. Longterm Pexp-changes determined using the new Ba transfer functions significantly agree with those derived from other methods (i.e. TOC) in open marine locations in the northern margin of the North Atlantic subtropical gyre over the last 40 ka and the last 330 ka in the equatorial divergence zone. Export productivity is shown to be 2-3 times higher than today during cold periods in the equatorial high productivity zone and possibly up to 6 times higher during stages 6 and 8. Productivity cycles are evidently controlled by the lateral advection of nutrient-rich intermediate waters from high southern latitudes.