138 research outputs found
A CASSCF Study of Various Rotamers of the Hexatriene Radical Cation
Results are presented from ab initio calculations on the ground and two low-lying excited states of the hexatriene radical cation in a variety of stable conformations of the electronic ground state of the molecule. We have performed Hartree-Fock geometry optimizations using the STO-3G and 6-31g basis sets and have performed vibrational analyses for all stable conformers in the 6-31G basis. In addition, we have performed geometry optimizations in both basis sets using CASSCF wave functions where the five π electrons are correlated. No new geometrical information is obtained at this level of treatment. Excitation energies to the two lowest-lying doublet π excited states for the six stable ground-state geometries were also calculated using CASSCF wave functions. These excitation energies are compared with previous experimental assignments of observed transitions in photolytically generated hexatriene radical cations
Resonance Raman Investigation of the Radical Cation of 1,3,5-Hexatriene
The resonance Raman spectrum of the 1,3,5-hexatriene radical cation generated by v-irradiation in a Freon glass is reported. The spectrum is excited at 395 nm in resonance with the second absorption band. Identical spectra are obtained from ionized (E)- and (Z)-1,3,5-hexatriene. The presence of more than one rotamer has to be assumed to account for all the observed resonance Raman bands. The bands are assigned to a mixture of the two rotamers, calculated at lowest energy, the ttt an tct rotamers, on the basis of ab initio ROHF/6-31G calculated harmonic frequencies. The spectrum indicates that the ttt and tct rotamers are formed in a ratio in the range 0.4./0.6-0.6/0.4. Two possible mechanisms are proposed to explain the presence of these two rotamers
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Use of the i2b2 research query tool to conduct a matched case–control clinical research study: advantages, disadvantages and methodological considerations
Background: A major aim of the i2b2 (informatics for integrating biology and the bedside) clinical data informatics framework aims to create an efficient structure within which patients can be identified for clinical and translational research projects. Our objective was to describe the respective roles of the i2b2 research query tool and the electronic medical record (EMR) in conducting a case-controlled clinical study at our institution. Methods: We analyzed the process of using i2b2 and the EMR together to generate a complete research database for a case–control study that sought to examine risk factors for kidney stones among gastrostomy tube (G-tube) fed children. Results: Our final case cohort consisted of 41/177 (23%) of potential cases initially identified by i2b2, who were matched with 80/486 (17%) of potential controls. Cases were 10 times more likely to be excluded for inaccurate coding regarding stones vs. inaccurate coding regarding G-tubes. A majority (67%) of cases were excluded due to not meeting clinical inclusion criteria, whereas a majority of control exclusions (72%) occurred due to inadequate clinical data necessary for study completion. Full dataset assembly required complementary information from i2b2 and the EMR. Conclusions: i2b2 was critical as a query analysis tool for patient identification in our case–control study. Patient identification via procedural coding appeared more accurate compared with diagnosis coding. Completion of our investigation required iterative interplay of i2b2 and the EMR to assemble the study cohort
Genome-wide analysis of lectin receptor-like kinases in Populus
Transcript level of C-type PtLecRLK gene in 24 different datasets from the Populus Gene Atlas Study. RNA-seq data were collected from the Populus Gene Atlas Study in Phytozome v11.0 ( http://phytozome.jgi.doe.gov/pz/portal.html ). The transcript level was expressed as FPKM. The sheet labeled as “whole_set” contains the original FPKM values from Gene Atlas. The data of four different tissues under standard condition are sorted in the data sheet labeled as “standard”. (XLSX 10 kb
Teaching assistants, computers and classroom management: evidence from a randomised control trial
Many students still leave school without a good grasp of basic literacy, despite the negative implications for future educational and labour market outcomes. We evaluate a programme that involves changing how resources are used within classrooms to reinforce the teaching of literacy. Specifically, the programme involves training teaching assistants to deliver a tightly structured package of materials to groups of young children. Further, we compare the effectiveness of computer-aided instruction using available software with the paper equivalent. We implement the experiment in the context of a Randomised Control Trial in English schools. Both interventions have a short-term impact on children’s reading scores, although the effect is bigger for the paper intervention and more enduring in the subsequent year. This paper shows how teaching assistants can be used to better effect within schools, and at a low cost
Patient experiences of anxiety, depression and acute pain after surgery: a longitudinal perspective
This study sought to explore the impact of the psychological variables anxiety and depression, on pain experience over time following surgery. Eighty-five women having major gynaecological surgery were assessed for anxiety, depression and pain after surgery. To gain further understanding, 37 patients participated in a semi-structured taped telephone interview 4–6 weeks post-operatively.
Pre-operative anxiety was found to be predictive of post-operative anxiety on Day 2, with patients who experienced high levels of anxiety before surgery continuing to feel anxious afterwards. By Day 4 both anxiety and depression scores increased as pain increased and one-third of the sample experienced levels of anxiety in psychiatric proportions whilst under one-third experienced similar levels of depression.
These findings have significant implications for the provision of acute pain management after surgery. Future research and those managing acute pain services need to consider the multidimensional effect of acute pain and the interface between primary and secondary care
On the making and taking of professionalism in the further education workplace
This paper examines the changing nature of professional practice in English further education. At a time when neo-liberal reform has significantly impacted on this under-researched and over-market-tested sector, little is known about who its practitioners are and how they construct meaning in their work. Sociological interest in the field has tended to focus on further education practitioners as either the subjects of market and managerial reform or as creative agents operating within the contradictions of audit and inspection cultures. In challenging such dualism, which is reflective of wider sociological thinking, the paper examines the ways in which agency and structure combine to produce a more transformative conception of the further education professional. The approach contrasts with a prevailing policy discourse that seeks to re-professionalise and modernise further education practice without interrogating either the terms of its professionalism or the neo-liberal practices in which it resides
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