2,108 research outputs found
Do Indirect Cost Rates Matter?
This study addresses the relationship between a university\u27s indirect cost rate and its level of federal research funding. Both direct and indirect cost funding are examined. The data used in the analyses include unpublished institutional level data for all doctoral and research universities on funding and indirect cost rates obtained from the National Science Foundation for the fiscal years 1988 to 1997 period. Our major finding is that higher indirect cost rates are associated with higher levels of direct and indirect cost funding for institutions that initially are among the largest recipients of federal funding. In contrast, for universities initially in the lower tail of funding recipients, higher indirect cost rates are associated with lower levels of direct and indirect cost funding.
This pattern of results is hypothesized to be based upon an institution\u27s indirect cost rate serving primarily as a price of research for lesser institutions but serving primarily as a proxy for the quality of the institution\u27s research infrastructure for the major recipients of federal funds. Our findings are consistent with the observation that since 1990 both indirect cost rates and shares of research funding for major private research universities have tended to decline. We find no evidence that faculty at major research universities are disadvantaged in their quests for external research funding by high indirect cost rates
Atomistic Insight into the Role of Threonine 127 in the Functional Mechanism of Channelrhodopsin-2
Channelrhodopsins (ChRs) belong to the unique class of light-gated ion channels. The structure of channelrhodopsin-2 from Chlamydomonas reinhardtii (CrChR2) has been resolved, but the mechanistic link between light-induced isomerization of the chromophore retinal and channel gating remains elusive. Replacements of residues C128 and D156 (DC gate) resulted in drastic effects in channel closure. T127 is localized close to the retinal Schiff base and links the DC gate to the Schiff base. The homologous residue in bacteriorhodopsin (T89) has been shown to be crucial for the visible absorption maximum and dark–light adaptation, suggesting an interaction with the retinylidene chromophore, but the replacement had little effect on photocycle kinetics and proton pumping activity. Here, we show that the T127A and T127S variants of CrChR2 leave the visible absorption maximum unaffected. We inferred from hybrid quantum mechanics/molecular mechanics (QM/MM) calculations and resonance Raman spectroscopy that the hydroxylic side chain of T127 is hydrogen-bonded to E123 and the latter is hydrogen-bonded to the retinal Schiff base. The C=N–H vibration of the Schiff base in the T127A variant was 1674 cm−1, the highest among all rhodopsins reported to date. We also found heterogeneity in the Schiff base ground state vibrational properties due to different rotamer conformations of E123. The photoreaction of T127A is characterized by a long-lived P2380 state during which the Schiff base is deprotonated. The conservative replacement of T127S hardly affected the photocycle kinetics. Thus, we inferred that the hydroxyl group at position 127 is part of the proton transfer pathway from D156 to the Schiff base during rise of the P3530 intermediate. This finding provides molecular reasons for the evolutionary conservation of the chemically homologous residues threonine, serine, and cysteine at this position in all channelrhodopsins known so far
Rapid colour changes in Euglena sanguinea (Euglenophyceae) caused by internal lipid globule migration
The accumulation of red pigments under chronic stress is a response observed in most
groups of oxygenic photoautotrophs. It is thought that the red pigments in the cell shield
the chlorophyll located underneath from the light. Among these red pigments, the
accumulation of carotenoids is one of the most frequent cases. However, the synthesis
or degradation of carotenoids is a slow process and this response is usually only
observed when the stress is maintained over a period of time. In the Euglenophyte
Euglena sanguinea, this is due to the accumulation of a large amount of free and
esterified astaxanthin (representing 80% of the carotenoid pool). While reddening is a
slow and sometimes irreversible process in other phototrophs, reducing the efficiency of
light harvesting by chlorophyll, in E. sanguinea it is highly dynamic, capable of shifting
from red to green (and vice-versa) in 10-20 min. This change is not due to de novo
carotenogenesis, but to the relocation of cytoplasmic lipid globules where astaxanthin
accumulates. Thus, red globules migrate from the centre of the cell to peripheral
locations when photoprotection is demanded. This protective system seems to be so
efficient that other classical mechanisms are not operative in this species. For example,
despite the presence and operation of the diadino-diatoxanthin cycle, nonphotochemical
quenching (NPQ) is almost undetectable. Since E. sanguinea forms
extensive floating colonies, reddening can be observed at much greater scale than at a
cellular level, the mechanism described here being one of the fastest and most dramatic
colour changes attributable to photosynthetic organisms at cell and landscape level. In
sum, these data indicate an extremely dynamic and efficient photoprotective mechanism
based on organelle migration more than on carotenoid biosynthesis that prevents excess
light absorption by chlorophylls reducing the need for other protective processes related
to energy dissipation.This work was supported by the Basque Government [UPV/EHU-GV IT-1018-16] [UPV/EHU PPG17/67 – GV IT-1040-16], and by the Spanish Ministry of Economy and Competitiveness (MINECO) and the European Research and Development Foundation (FEDER) through (i) [CTM2014-53902-C2-2-P] national grant and (ii) a “Juan de la Cierva-Incorporación” postdoctoral grant [IJCI-2014-22489] to BFM
Hindered Aluminum Plating and Stripping in Urea/NMA/Al(OTF) as a Cl-Free Electrolyte for Aluminum Batteries
Conventional electrolytes for aluminum metal batteries are highly corrosive because they must remove the AlO layer to enable plating and stripping. However, such corrosiveness impacts the stability of all cell parts, thus hampering the real application of aluminum-metal batteries. The urea/NMA/Al(OTF) electrolyte is a non-corrosive alternative to the conventional [EMImCl]: AlCl ionic liquid electrolyte (ILE). Unfortunately, this electrolyte demonstrates poor Al plating/stripping, probably because (being not corrosive) it cannot remove the AlO passivation layer. This work proves that no plating/stripping occurs on the Al electrode despite modifying the Al surface. We highlight how urea/NMA/Al(OTF) electrolyte and the state of the Al electrode surface impact the interphase layer formation and, consequently, the likelihood and reversibility of Al plating/stripping. We point up the requirement for carefully drying electrolyte mixture and components, as water results in hydrogen evolution reaction and creation of an insulating interphase layer containing Al(OH), AlF, and re-passivated Al oxide, which finally blocks the path for the possible Al plating/stripping
Magnetic properties of the Kagom mixed compounds CoxNi1 x 3V2O8
The magnetic properties of the mixed compounds CoxNi1 x 3 V2O8 CNVO investigated by magnetization and neutron diffraction measurements are presented. Unlike their parent compounds Ni3V2O8 NVO and Co3V2O8 CVO , only one magnetic phase transition into an antiferromagnetic phase was detected for powder samples with x 0.27, 0.52, and 0.76. The magnetic structures are modulated according to a propagation vector k delta,0,0 with delta being dependent on the composition parameter x. Furthermore, magnetization data of a CVO single crystal is featured, which is qualitatively different from previous publications and exhibits a controversial aspect concerning the behavior of the curve under an applied magnetic field along the b axi
Do Indirect Costs Matter?
This study addresses the relationship between a university's indirect cost rate and its level of federal research funding. Both direct and indirect cost funding are examined. The data used in the analyses include unpublished institutional level data for all doctoral and research universities on funding and indirect cost rates obtained from the National Science Foundation for the fiscal years 1988 to 1997 period. Our major finding is that higher indirect cost rates are associated with higher levels of direct and indirect cost funding for institutions that initially are among the largest recipients of federal funding. In contrast, for universities initially in the lower tail of funding recipients, higher indirect cost rates are associated with lower levels of direct and indirect cost funding. This pattern of results is hypothesized to be based upon an institution's indirect cost rate serving primarily as a price' of research for lesser institutions but serving primarily as a proxy for the quality of the institution's research infrastructure for the major recipients of federal funds. Our findings are consistent with the observation that since 1990 both indirect cost rates and shares of research funding for major private research universities have tended to decline. We find no evidence that faculty at major research universities are disadvantaged in their quests for external research funding by high indirect cost rates.
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