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1.
Res High Educ ; 63(7): 1158-1203, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35341018

RESUMO

University athletics because of its reporting structure, regulation by the NCAA, and relationship to the academic enterprise of institutions, provides a unique look into postsecondary institutional behavior. Using a difference-in-difference design, this study tests the introduction of new television networks dedicated to college sports on institutional subsidy levels for athletics. Overall, our findings show that institutions are responsive to the introduction of new college-sports-dedicated television networks. When considering institutions in the Power Five athletic conferences, we find an average decline in subsidy levels of approximately $1.2 million. When considering different types of subsidies, we find significant declines in direct subsidies and student fees, but no significant change for indirect subsidies.

2.
Res High Educ ; 63(6): 899-932, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35125626

RESUMO

In 2015, Idaho adopted the nation's first direct admissions system and proactively admitted all high school graduates to a set of public institutions. This reimagination of the admissions process may reduce barriers to students' enrollment and improve access across geographic and socioeconomic contexts by removing many human capital, informational, and financial barriers in the college search and application process. Despite a lack of evidence on the efficacy of direct admissions systems, the policy has already been proposed or implemented in four other states. Using synthetic control methods, we estimate the first causal impacts of direct admissions on institutional enrollment outcomes. We find early evidence that direct admissions increased first-time undergraduate enrollments by 4-8% (50-100 students per campus on average) and in-state levels by approximately 8-15% (80-140 students) but had minimal-to-no impacts on the enrollment of Pell-eligible students. These enrollment gains were concentrated among 2-year, open-access institutions. We discuss these findings in relation to state contexts and policy design given the emergence of literature highlighting the varied efficacy of similar college access policies.

3.
Appl Environ Microbiol ; 87(17): e0079421, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34190607

RESUMO

Genome and proteome data predict the presence of both the reductive citric acid cycle (rCAC; also called the reductive tricarboxylic acid cycle) and the Calvin-Benson-Bassham cycle (CBB) in "Candidatus Endoriftia persephonae," the autotrophic sulfur-oxidizing bacterial endosymbiont from the giant hydrothermal vent tubeworm Riftia pachyptila. We tested whether these cycles were differentially induced by sulfide supply, since the synthesis of biosynthetic intermediates by the rCAC is less energetically expensive than that by the CBB. R. pachyptila was incubated under in situ conditions in high-pressure aquaria under low (28 to 40 µmol · h-1) or high (180 to 276 µmol · h-1) rates of sulfide supply. Symbiont-bearing trophosome samples excised from R. pachyptila maintained under the two conditions were capable of similar rates of CO2 fixation. Activities of the rCAC enzyme ATP-dependent citrate lyase (ACL) and the CBB enzyme 1,3-bisphosphate carboxylase/oxygenase (RubisCO) did not differ between the two conditions, although transcript abundances for ATP-dependent citrate lyase were 4- to 5-fold higher under low-sulfide conditions. δ13C values of internal dissolved inorganic carbon (DIC) pools were varied and did not correlate with sulfide supply rate. In samples taken from freshly collected R. pachyptila, δ13C values of lipids fell between those collected for organisms using either the rCAC or the CBB exclusively. These observations are consistent with cooccurring activities of the rCAC and the CBB in this symbiosis. IMPORTANCE Previous to this study, the activities of the rCAC and CBB in R. pachyptila had largely been inferred from "omics" studies of R. pachyptila without direct assessment of in situ conditions prior to collection. In this study, R. pachyptila was maintained and monitored in high-pressure aquaria prior to measuring its CO2 fixation parameters. Results suggest that ranges in sulfide concentrations similar to those experienced in situ do not exert a strong influence on the relative activities of the rCAC and the CBB. This observation highlights the importance of further study of this symbiosis and other organisms with multiple CO2-fixing pathways, which recent genomics and biochemical studies suggest are likely to be more prevalent than anticipated.


Assuntos
Gammaproteobacteria/fisiologia , Poliquetos/microbiologia , Simbiose , Animais , Processos Autotróficos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Ciclo do Ácido Cítrico , Gammaproteobacteria/classificação , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Fontes Hidrotermais/microbiologia , Fontes Hidrotermais/parasitologia , Fotossíntese , Poliquetos/fisiologia , Sulfetos/metabolismo , Enxofre/metabolismo
4.
FEMS Microbiol Lett ; 364(14)2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28854673

RESUMO

The genome sequence of the obligate chemolithoautotroph Hydrogenovibrio crunogenus paradoxically predicts a complete oxidative citric acid cycle (CAC). This prediction was tested by multiple approaches including whole cell carbon assimilation to verify obligate autotrophy, phylogenetic analysis of CAC enzyme sequences and enzyme assays. Hydrogenovibrio crunogenus did not assimilate any of the organic compounds provided (acetate, succinate, glucose, yeast extract, tryptone). Enzyme activities confirmed that its CAC is mostly uncoupled from the NADH pool. 2-Oxoglutarate:ferredoxin oxidoreductase activity is absent, though pyruvate:ferredoxin oxidoreductase is present, indicating that sequence-based predictions of substrate for this oxidoreductase were incorrect, and that H. crunogenus may have an incomplete CAC. Though the H. crunogenus CAC genes encode uncommon enzymes, the taxonomic distribution of their top matches suggests that they were not horizontally acquired. Comparison of H. crunogenus CAC genes to those present in other 'Proteobacteria' reveals that H. crunogenus and other obligate autotrophs lack the functional redundancy for the steps of the CAC typical for facultative autotrophs and heterotrophs, providing another possible mechanism for obligate autotrophy.


Assuntos
Carbono/metabolismo , Ciclo do Ácido Cítrico , Fontes Hidrotermais/microbiologia , Piscirickettsiaceae/metabolismo , Crescimento Quimioautotrófico , Glucose/metabolismo , Oxirredução , Filogenia , Piscirickettsiaceae/classificação , Piscirickettsiaceae/genética , Ácido Pirúvico/metabolismo
5.
J Appl Behav Anal ; 40(3): 541-4, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17970267

RESUMO

The present study extends the growing behavioral literature on indices of happiness for persons with developmental disabilities to the geriatric population. Data on indices of emotional affect (i.e., happiness) were collected prior to, during, and after each resident was exposed to environmental enhancement activities of various durations. Results showed that every activity improved each resident's level of happiness when compared to pre- and postactivity levels. These outcomes suggest that indexing affect may be as useful for nursing home residents as it has been for individuals with developmental disabilities.


Assuntos
Doença de Alzheimer/epidemiologia , Doença de Alzheimer/psicologia , Felicidade , Casas de Saúde/estatística & dados numéricos , Meio Social , Afeto , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Transtornos Mentais/psicologia , Variações Dependentes do Observador , Inquéritos e Questionários
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