The Sustainability of Success: Distinguishing the Lucky from the Good in the Stacked Deck of Academic Accounting

Almost all accounting doctoral graduates strive to publish their dissertations in one of the top three journals in the academic accounting discipline. This study first replicates and extends prior work to show that students that earn their degrees from more prestigious programs and those that take faculty positions at more prestigious schools are more likely to succeed in this endeavor. Furthermore, this paper demonstrates that working with individuals that have been successful publishing in the top three journals provides the advantage of sustained research productivity in these mainstream journals. Implications for academic careers and employment are drawn

Moisture interaction and stability of ZOT (Zinc Orthotitanate) thermal control spacecraft coating

Two of the many performance requirements of the zinc orthotitanate (ZOT) ceramic thermal control paint covering parts of the Jupiter-bound Galileo spacecraft are that it be sufficiently electrically conductive so as to prevent electrostatic discharge (ESD) damage to onboard electronics and that it adhere to and protect the substrate from corrosion in terrestrial environments. The bulk electrical resistivity of ZOT on an aluminum substrate was measured over the ranges 22 C to 90 C and 0 percent RH to 100 percent RH, and also in soft (10 (minus 2) Torr) and hard (10 (minus 7) Torr) vacuums. No significant temperature dependence was evident, but measured resistivity values ranged over 9 orders of magnitude: 10 to the 5th power ohm-cm at 100 percent RH greater than 10 to the 12th power ohm-cm in a hard vacuum. The latter value violates the ESD criterion for a typical 0.019 cm thick coating. The corrosion study involved exposing typical ZOT substrate combinations to two moisture environments - 30 C/85 percent RH and 85 C/85 percent RH - for 2000 hours, during which time the samples were periodically removed for front-to-back electrical resistance and scratch/peel test measurements. It was determined that the ZOT/Al and ZOT/Mg systems are stable (no ZOT delamination), although some corrosion (oxide formation) and resistivity increases observed among the ZOT/Mg samples warrant that exposure of some parts to humid environments be minimized

Interrogation of alternative splicing events in duplicated genes during evolution

<p>Abstract</p> <p>Background</p> <p>Gene duplication provides resources for developing novel genes and new functions while retaining the original functions. In addition, alternative splicing could increase the complexity of expression at the transcriptome and proteome level without increasing the number of gene copy in the genome. Duplication and alternative splicing are thought to work together to provide the diverse functions or expression patterns for eukaryotes. Previously, it was believed that duplication and alternative splicing were negatively correlated and probably interchangeable.</p> <p>Results</p> <p>We look into the relationship between occurrence of alternative splicing and duplication at different time after duplication events. We found duplication and alternative splicing were indeed inversely correlated if only recently duplicated genes were considered, but they became positively correlated when we took those ancient duplications into account. Specifically, for slightly or moderately duplicated genes with gene families containing 2 - 7 paralogs, genes were more likely to evolve alternative splicing and had on average a greater number of alternative splicing isoforms after long-term evolution compared to singleton genes. On the other hand, those large gene families (contain at least 8 paralogs) had a lower proportion of alternative splicing, and fewer alternative splicing isoforms on average even when ancient duplicated genes were taken into consideration. We also found these duplicated genes having alternative splicing were under tighter evolutionary constraints compared to those having no alternative splicing, and had an enrichment of genes that participate in molecular transducer activities.</p> <p>Conclusions</p> <p>We studied the association between occurrences of alternative splicing and gene duplication. Our results implicate that there are key differences in functions and evolutionary constraints among singleton genes or duplicated genes with or without alternative splicing incidences. It implies that the gene duplication and alternative splicing may have different functional significance in the evolution of speciation diversity.</p

Membrane-based TBADT recovery as a strategy to increase the sustainability of continuous-flow photocatalytic HAT transformations

Photocatalytic hydrogen atom transfer (HAT) processes have been the object of numerous studies showcasing the potential of the homogeneous photocatalyst tetrabutylammonium decatungstate (TBADT) for the functionalization of C(sp(3))–H bonds. However, to translate these studies into large-scale industrial processes, careful considerations of catalyst loading, cost, and removal are required. This work presents organic solvent nanofiltration (OSN) as an answer to reduce TBADT consumption, increase its turnover number and lower its concentration in the product solution, thus enabling large-scale photocatalytic HAT-based transformations. The operating parameters for a suitable membrane for TBADT recovery in acetonitrile were optimized. Continuous photocatalytic C(sp(3))-H alkylation and amination reactions were carried out with in-line TBADT recovery via two OSN steps. Promisingly, the observed product yields for the reactions with in-line catalyst recycling are comparable to those of reactions performed with pristine TBADT, therefore highlighting that not only catalyst recovery (>99%, TON > 8400) is a possibility, but also that it does not happen at the expense of reaction performance

First-in-Human Phase I Study to Evaluate the Brain-Penetrant PI3K/mTOR Inhibitor GDC-0084 in Patients with Progressive or Recurrent High-Grade Glioma.

PurposeGDC-0084 is an oral, brain-penetrant small-molecule inhibitor of PI3K and mTOR. A first-in-human, phase I study was conducted in patients with recurrent high-grade glioma.Patients and methodsGDC-0084 was administered orally, once daily, to evaluate safety, pharmacokinetics (PK), and activity. Fluorodeoxyglucose-PET (FDG-PET) was performed to measure metabolic responses.ResultsForty-seven heavily pretreated patients enrolled in eight cohorts (2-65 mg). Dose-limiting toxicities included 1 case of grade 2 bradycardia and grade 3 myocardial ischemia (15 mg), grade 3 stomatitis (45 mg), and 2 cases of grade 3 mucosal inflammation (65 mg); the MTD was 45 mg/day. GDC-0084 demonstrated linear and dose-proportional PK, with a half-life (∼19 hours) supportive of once-daily dosing. At 45 mg/day, steady-state concentrations exceeded preclinical target concentrations producing antitumor activity in xenograft models. FDG-PET in 7 of 27 patients (26%) showed metabolic partial response. At doses ≥45 mg/day, a trend toward decreased median standardized uptake value in normal brain was observed, suggesting central nervous system penetration of drug. In two resection specimens, GDC-0084 was detected at similar levels in tumor and brain tissue, with a brain tissue/tumor-to-plasma ratio of &gt;1 and &gt;0.5 for total and free drug, respectively. Best overall response was stable disease in 19 patients (40%) and progressive disease in 26 patients (55%); 2 patients (4%) were nonevaluable.ConclusionsGDC-0084 demonstrated classic PI3K/mTOR-inhibitor related toxicities. FDG-PET and concentration data from brain tumor tissue suggest that GDC-0084 crossed the blood-brain barrier

Redox Switchable Thianthrene Cavitands

A redox activated vase-to-kite conformational change is reported for a new resorcinarene-based cavitand appended with four quinoxaline-fused thianthrene units. In its neutral state, the thianthrene-containing cavitand was shown by 1H NMR to adopt a closed vase conformation. Upon oxidation the electrostatic repulsion among the thianthrene radical cations promotes a kite conformation in the thianthrene-containing cavitand. The addition of acid produced a shoulder feature below 300 nm in the cavitand’s UV-Vis spectrum that we have assigned to the vase-to-kite conformation change. UV-Vis spectroelectrochemical studies of the cavitand revealed a development of a similar shoulder peak consistent with the oxidation-induced vase-to-kite conformation change. To support that the shoulder peak is diagnostic for a vase-to-kite conformation change, a model molecule constituting a single quinoxaline wall of the cavitand was synthesized and studied. As expected UV-Vis spectroelectrochemical studies of the cavitand arm did not display a shoulder peak below 300 nm. The oxidation-induced vase-to-kite conformation is further confirmed by the distinctive upfield shift in 1H chemical shift of the methine signal. Key words: redox active, thianthrene, resorcinarene cavitands, electrochemical switching, conformation changeNational Science Foundation (U.S.). Center for Energy Efficient Electronics Science (Award ECCS0939514)Singapore. Agency for Science, Technology and Research (Graduate Scholarship