Strongly aligned molecules inside helium droplets in the near-adiabatic regime

Iodine (I$_2$) molecules embedded in He nanodroplets are aligned by a 160 ps long laser pulse. The highest degree of alignment, occurring at the peak of the pulse and quantified by $\langle \cos^2 \theta_{2D} \rangle$, is measured as a function of the laser intensity. The results are well described by $\langle \cos^2 \theta_{2D} \rangle$ calculated for a gas of isolated molecules each with an effective rotational constant of 0.6 times the gas-phase value, and at a temperature of 0.4 K. Theoretical analysis using the angulon quasiparticle to describe rotating molecules in superfluid helium rationalizes why the alignment mechanism is similar to that of isolated molecules with an effective rotational constant. A major advantage of molecules in He droplets is that their 0.4 K temperature leads to stronger alignment than what can generally be achieved for gas phase molecules -- here demonstrated by a direct comparison of the droplet results to measurements on a $\sim$ 1 K supersonic beam of isolated molecules. This point is further illustrated for more complex system by measurements on 1,4-diiodobenzene and 1,4-dibromobenzene. For all three molecular species studied the highest values of $\langle \cos^2 \theta_{2D} \rangle$ achieved in He droplets exceed 0.96.Comment: 11 pages, 8 figure

The abrasive wear resistance of austempered spheroidal graphite irons

Bibliography: pages 103-107.A study has been made of the structure and abrasive wear resistance of two austempered commercial spheroidal cast irons. Heat treatments have been carried out for different times between 2 and 120 minutes for a range of austenitising temperatures between 850°C and 950°C and austempering temperatures between 250°C and 450°C. The morphology and constitution of the resulting dual phase ferrite/austenite structure has been examined using optical and scanning electron microscopy and x-ray analysis. The maximum quantity of retained austenite in the structure has been shown to vary up to 50% and to be strongly dependent on heat treatment parameters and the composition of the iron. Laboratory abrasive wear testing has been carried out on these austempered irons and compared with the results of similar tests on a range of abrasion resistant carbon steels. All the austempered irons were found to have better abrasion resistance than proprietary abrasion resistant steels. These austempered irons derive their outstanding properties from the morphology of the dual phase ferritic/austenitic matrix coupled to the high work hardening characteristics brought about by the stress induced austenite to martensite transformation during abrasion. The influence of microstructure and mechanically induced transformation has been studied as a function of austempering temperature and time

Project-based science for general education college students and seventh graders: Pitfalls and pointers

We teach a general-education science course for honors students, who in turn mentor disadvantaged seventh graders through a water quality investigation of a local stream. Activities for both groups involve all aspects of a scientific project: scientific background, local context, project design, data collection and analysis, and communication of scientific results. On successive weeks, we first lead our college students through each step in the process then the honors students mentor middle school students through those same steps. College and middle school teachers act as facilitators, and each honors student is responsible for about 6 to 8 middle schoolers. The college students and 7th graders often form strong bonds during their work together. The project explores nutrient (ammonium, NH4; nitrate, NO3, phosphate, PO4) and fecal microbe (Escherichia coli) contamination within the stream, as well as macroinvertebrate distribution and abundance, which is affected by overall water quality. Both student groups are responsible for documenting project activities in a project notebook. Once we establish background principles and context, both college and middle school students sample stream water and fauna. Selected students measure nutrient and E. coli concentrations in water samples, whereas all students pick and identify macroinvertebrates from 4 stations. Students then analyze all data to identify probable contamination sources and to assess water quality using established macroninvertebrate indices. Honors students give oral group presentations on their project findings in class. The project culminates when the 7th graders come to campus and present their work with oral and poster presentations. We invite parents, interested water-quality experts, and local dignitaries to the presentation event. Coordination of supporting college class content, supporting middle school class content, and project activities for both student groups - especially the middle school sampling trip to the stream - requires careful planning, shuffling of middle school schedules, and enthusiastic support by all instructors and administrative educators. Also, preparatory instruction and practice for college students in project activities is key, so they feel more comfortable in mentoring 7th graders

Project-oriented science instruction involving general-education undergraduates serving as mentors to underprivileged middle-students students

We report results from a novel, project-based science course funded by the NSF for general-education students in the EKU Honors Program and for middle school students. Key aspects of the course are: (1) instruction in the natural sciences adopting a regional context; (2) investigation of the water quality of a local stream involving all portions of a scientific study from planning to data collection and analysis to presentation; and (3) direct mentoring of underprivileged, seventh-grade students by honors students in project activities, including trips to campus for laboratory work and presentations. The course is meant to provide high-quality scientific instruction and serve as an improved model for general-education science courses, while teaching project-based science to all students. Moreover, we train our college students to become self-directed learners by giving them responsibility in engaging and mentoring at-risk, middle-school students while promoting STEM. The deep involvement of middle-school teachers in planning and implementation is crucial. The course instructs and promotes science at several different levels. We engage honors students using experiments, simulations, and field trips to illustrate fundamental scientific concepts while exploring geological and biological aspects particular to eastern Kentucky. The project is an investigation of the water chemistry and ecosystem of a typical stream, which experiences anthropogenic contamination by nutrients and fecal microbes as determined by land use. We first lead college students through each step of the project over a period of 8 weeks, and then they lead middle school students serially through those same steps. A key aspect of the project is travel to a local stream where every student engages in sampling activities. For our college students, the project culminates in a report written as a scientific paper. The seventh graders form groups and present oral and poster presentations to regional watershed experts and parents. We use pre- and post-course tests, attitudinal surveys, and focus groups to examine the efficacy of the course in fostering understanding of science concepts, increasing understanding of the environmental problems of a geographic region, and improving attitudes toward science for college and middle-school students

Rotational coherence spectroscopy of molecules in helium nanodroplets: Reconciling the time and the frequency domains

Alignment of OCS, CS$_2$ and I$_2$ molecules embedded in helium nanodroplets is measured as a function of time following rotational excitation by a non-resonant, comparatively weak ps laser pulse. The distinct peaks in the power spectra, obtained by Fourier analysis, are used to determine the rotational, B, and centrifugal distortion, D, constants. For OCS, B and D match the values known from IR spectroscopy. For CS$_2$ and I$_2$, they are the first experimental results reported. The alignment dynamics calculated from the gas-phase rotational Schr\"{o}dinger equation, using the experimental in-droplet B and D values, agree in detail with the measurement for all three molecules. The rotational spectroscopy technique for molecules in helium droplets introduced here should apply to a range of molecules and complexes.Comment: ASC and LC contributed equally. 7 pages, 3 figure

Culture, government, and spatiality: re-assessing the 'Foucault effect' in cultural-policy studies

This article critically discusses the reconceptualization of culture and governmentality in recent Australian ‘cultural–policy studies’. It argues that the further development of this conceptualization requires a more careful consideration of the complex relations between culture, power and the different spatialities of social practices. The assumptions of this literature regarding social-democratic public institutions and the nation-state are critically addressed in the light of contemporary processes of globalization. It is argued that the use made of Foucault in this paradigm privileges a model of disciplinary power which is dependent on a particular spatialization of social subjects and technologies of the self. As a result, an uncritical application of this model to all cultural practices supports a far too coherent image of practices of ‘government’ in producing sought-after subject-effects. It is suggested that the different articulations of spatio-temporal presence and absence in cultural technologies require a less totalizing understanding of the forms of power exercised through governmental practices

Development of a patient-reported outcome measure for gastrointestinal recovery after surgery (PRO-diGI)

Background After major abdominal surgery, patients may experience significant gastrointestinal dysfunction, including postoperative ileus. Many clinical tools are used to measure this dysfunction, but there is no patient-reported outcome measure (PROM) specific to this group. The aim of this study was to develop a new PROM for this common condition. Methods A four-stage approach was undertaken. Stage 1 used semi-structured interviews with 29 patients to explore experiences of gastrointestinal recovery and develop a draft questionnaire. Stage 2 solicited feedback from 18 patients and 15 clinical experts on the face validity of the proposed tool using the Questionnaire on Questionnaires (QQ-10). Stage 3 recruited 297 patients to complete the questionnaire. Principal component analysis reduced the items and identified the domain structure. Test-retest reliability and a pilot assessment of responsiveness were assessed in stage 4 in a sample of 100 patients and in a sample of 68 patients respectively. Results The interviews generated 26 subthemes across gastrointestinal recovery and general well-being. An initial questionnaire containing 44 items was developed. The QQ-10 demonstrated high value and low burden, supporting face validity. Tests to reduce the items and identify the domain structure resulted in a 15-item questionnaire across four domains (nausea, eating, well-being, and bowels). Test-retest reliability showed intraclass correlation coefficient values ≥0.7 for all domains. Pilot responsiveness was demonstrated through differences in pre- and post-surgical scores. Conclusion PRO-diGI is a PROM for gastrointestinal dysfunction after major abdominal surgery that shows good psychometric properties and demonstrates face validity, reliability, and responsiveness. This now needs external validation to facilitate broader implementation