1,432 research outputs found
A Study of the Winter Diatoms (Bacillariophyceae) Flora in Fall Creek, Indiana
The diatom flora was studied at four stations on Fall Creek upstream from its confluence with White River at Tenth Street, Indianapolis, Indiana, over a three month period, December through February 1961-2. The entire course of the Creek studied was classified as fairly clean water. Pollution was due largely to contamination by sanitary wastes. The water had an average temperature of 2.5ÂşC and an average of slightly alkaline reaction. The communities were composed of a few species well represented and many species sparsely represented
Historical Relationships of Atlantic Slope River Drainages
An analysis of the historical relationships of 19 river drainages (St. Lawrence to Altamaha) on the Atlantic slope of the Appalachian Mountains was conducted using the shared presence of 124 native species of cyprinid fishes. This analysis resulted in an area cladogram that suggests that the rivers of the southern Atlantic slope were historically connected to the drainage of three southern rivers (Flint, Chattahoochee, and Apalachicola) which drain into the Gulf of Mexico. The mid Atlantic and northern Atlantic slope rivers appear to be historically related in support of earlier hypotheses that the mid Atlantic region provided a refugium for fishes to disperse to the north following the retreat of the glacier and rising sea levels at the end of the Pleistocene. Methods for testing these conclusions are discussed
Facile O-atom insertion into C-C and C-H bonds by a trinuclear copper complex designed to harness a singlet oxene
Two trinuclear copper [CuICuICuI(L)]1+ complexes have been prepared with the multidentate ligands (L) 3,3'-(1,4-diazepane-1,4-diyl)bis(1-((2-(dimethylamino)ethyl)(methyl)amino)propan-2-ol) (7-Me) and (3,3'-(1,4-diazepane-1,4-diyl)bis(1-((2-(diethylamino) ethyl)(ethyl) amino)propan-2-ol) (7-Et) as models for the active site of the particulate methane monooxygenase (pMMO). The ligands were designed to form the proper spatial and electronic geometry to harness a "singlet oxene," according to the mechanism previously suggested by our laboratory. Consistent with the design strategy, both [CuICuICuI(L)]1+ reacted with dioxygen to form a putative bis(µ3-oxo)CuIICuIICuIII species, capable of facile O-atom insertion across the central C-C bond of benzil and 2,3-butanedione at ambient temperature and pressure. These complexes also catalyze facile O-atom transfer to the C-H bond of CH3CN to form glycolonitrile. These results, together with our recent biochemical studies on pMMO, provide support for our hypothesis that the hydroxylation site of pMMO contains a trinuclear copper cluster that mediates C-H bond activation by a singlet oxene mechanism
Teaching for learning with technology: a faculty development initiative at a research university
This paper reviews recent literature addressing the state of
technology in higher education as a backdrop for a faculty
development program offered annually at Northwestern. First,
we will present the state of technology related to teaching in
three areas: (1) the varied institutional interest in technology,
(2) the variance in faculty engagement with technology, and (3)
factors that influence faculty acceptance of technology. Next,
we will introduce Northwestern’s response to the need for
faculty development related to technology, the 5-day Teaching
and Learning with Technology workshop. Finally, we will
present data gathered over two years that demonstrates how
pedagogically-driven technology training can enhance teaching
and encourage faculty to embrace technology in teaching to
accomplish pedagogically-based learning objectives
The Computer Science Ontology: A Large-Scale Taxonomy of Research Areas
Ontologies of research areas are important tools for characterising, exploring, and analysing the research landscape. Some fields of research are comprehensively described by large-scale taxonomies, e.g., MeSH in Biology and PhySH in Physics. Conversely, current Computer Science taxonomies are coarse-grained and tend to evolve slowly. For instance, the ACM classification scheme contains only about 2K research topics and the last version dates back to 2012. In this paper, we introduce the Computer Science Ontology (CSO), a large-scale, automatically generated ontology of research areas, which includes about 26K topics and 226K semantic relationships. It was created by applying the Klink-2 algorithm on a very large dataset of 16M scientific articles. CSO presents two main advantages over the alternatives: i) it includes a very large number of topics that do not appear in other classifications, and ii) it can be updated automatically by running Klink-2 on recent corpora of publications. CSO powers several tools adopted by the editorial team at Springer Nature and has been used to enable a variety of solutions, such as classifying research publications, detecting research communities, and predicting research trends. To facilitate the uptake of CSO we have developed the CSO Portal, a web application that enables users to download, explore, and provide granular feedback on CSO at different levels. Users can use the portal to rate topics and relationships, suggest missing relationships, and visualise sections of the ontology. The portal will support the publication of and access to regular new releases of CSO, with the aim of providing a comprehensive resource to the various communities engaged with scholarly data
Social Studies Preservice Teachers’ Citizenship Knowledge and Perceptions of the U.S. Naturalization Test
Teacher educators from six states invited their social studies methodology students to complete an abbreviated version of the U.S. Citizenship and Immigration Services (USCIS) Naturalization Test. The preservice teachers were also asked to share their conceptions of citizenship and evaluate the naturalization test. The findings from this study indicated that although this sample of preservice teachers had limited conceptions of citizenship, most were able to get a satisfactory score on the test. The authors discuss the implications of these results and suggest ways to broaden citizenship education in teacher preparation programs
Survival After Sublobar Resection versus Lobectomy for Clinical Stage IA Lung Cancer An Analysis from the National Cancer Data Base
BackgroundRecent data have suggested possible oncologic equivalence of sublobar resection with lobectomy for early-stage non–smallcell lung cancer (NSCLC). Our aim was to evaluate and compare short-term and long-term survival for these surgical approaches.MethodsThis retrospective cohort study utilized the National Cancer Data Base. Patients undergoing lobectomy, segmentectomy, or wedge resection for preoperative clinical T1A N0 NSCLC from 2003 to 2011 were identified. Overall survival (OS) and 30-day mortality were analyzed using multivariable Cox proportional hazards models, logistic regression models, and propensity score matching. Further analysis of survival stratified by tumor size, facility type, number of lymph nodes (LNs) examined, and surgical margins was performed.ResultsA total of 13,606 patients were identified. After propensity score matching, 987 patients remained in each group. Both segmentectomy and wedge resection were associated with significantly worse OS when compared with lobectomy (hazard ratio: 1.70 and 1.45, respectively, both p < 0.001), with no difference in 30-day mortality. Median OS for lobectomy, segmentectomy, and wedge resection were 100, 74, and 68 months, respectively (p < 0.001). Finally, sublobar resection was associated with increased likelihood of positive surgical margins, lower likelihood of having more than three LNs examined, and significantly lower rates of nodal upstaging.ConclusionIn this large national-level, clinically diverse sample of clinical T1A NSCLC patients, wedge and segmental resections were shown to have significantly worse OS compared with lobectomy. Further patients undergoing sublobar resection were more likely to have inadequate lymphadenectomy and positive margins. Ongoing prospective study taking into account LN upstaging and margin status is still needed
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