Identity development in career-changing beginning teachers : a qualitative study of professional scientists becoming school teachers

This qualitative study provides a critical case to analyse the identity development of professionals who already have a strong sense of identity as scientists and have decided to relinquish their professional careers to become teachers. The study followed a group of professionals who undertook a one-year teacher education course and were assigned to secondary and middle-years schools on graduation. Their experiences were examined through the lens of self-determination theory, which posits that autonomy, confidence and relationships are important in achieving job satisfaction. The findings indicated that those teachers who were able to achieve this sense of autonomy and confidence, and had established strong relationships with colleagues generated a positive professional identity as a teacher. The failure to establish supportive relationships was a decisive event that challenged their capacity to develop a strong sense of identity as a teacher

From Scientist to Science Teacher: A Career Change Teacher in Transition

One method of addressing the shortage of science and mathematics teachers is to train scientists and other science-related professionals to become teachers. Advocates argue that these career changers as discipline experts can relate the subject matter knowledge to various contexts and applications. In this paper, through interviews with a former scientist and her students, we examine how one career changer used her expertise in microbiology to teach microscopy. These interviews provided the basis for a description of the teacher’s instruction which was then analysed for components of domain knowledge for teaching. Consistent with the literature, the findings revealed that this career changer needed to develop her pedagogical knowledge. However, an interesting finding was that the teacher’s subject matter as a science teacher differed substantively from her knowledge as a scientist. This finding challenges the assumption that subject matter is transferable across professions and provides insight into how to better support career changers to transition from scientist to science teacher

The Effects of Low and High Gravity on Neurospora Crassa

We studied the effects of different gravity levels on Neurospora crassa and its morphology. This research was conducted by simulating low and high gravity effects in different operating procedures. For the low gravity simulation, the experiment was conducted by using a clinostat to constantly disorient the samples at a very slow rate. For the high gravity simulation, N. crassa was subjected to different amounts of g forces by placing the samples in a centrifuge and subjected the samples to increasing amounts of revolutions per minute. The results of these experiments conclude that in low-gravity situations, the N. crassa showed sparse growth and some cytoplasmic failure. In the high gravity situations, the samples showed that at around 1,000 to 2,000 RPMs, there were no changes in the morphology, but at higher RPMs like 3,000 or 4,000, there were some signs of cytoplasmic failure but no noticeable changes to morphology

African Entrepreneurs’ Perceptions on the Mentoring Provided by a Cross-cultural Professional Development Experience: Implications for Future Program

We conducted a multicase investigation to assess the impacts of a cross-cultural exchange program on Entrepreneur Fellows from Kenya, South Africa, and Uganda (8 women; 14 men) after they had returned home from the United States. Our assessment included the mentoring aspect of the program. Six questions and related probes guided semi-structured interviews with the 22 Fellows, the study’s quintain. The lead researcher transcribed the study’s interviews and verified accuracy and trustworthiness by sending her transcriptions to the Fellows for verification. Findings derived from the interviews or cases crystallized as themes representative of the quintain. The emergent themes, which included mentoring, inspired two theoretical lenses to guide our interpretation of the Fellows’ experiences: human capital theory and theory of planned behavior. Recommendations for practice include additional training of entrepreneur mentors and suggestions to facilitate high-quality field experiences. Additional research examining participants’ views about mentoring – protégés and their mentors – as an integral component of entrepreneurial training in cross-cultural settings, and how that can be improved, would likely enhance the learning outcomes of similar programs

Deformation Associated with Ghost Craters and Basins in Volcanic Smooth Plains on Mercury: Strain Analysis and Implications for Plains Evolution

Since its insertion into orbit about Mercury in March 2011, the MESSENGER spacecraft has imaged most previously unseen regions of the planet in unprecedented detail, revealing extensive regions of contiguous smooth plains at high northern latitudes and surrounding the Caloris basin. These smooth plains, thought to be emplaced by flood volcanism, are populated with several hundred ghost craters and basins, nearly to completely buried impact features having rims for which the surface expressions are now primarily rings of deformational landforms. Associated with some ghost craters are interior groups of graben displaying mostly polygonal patterns. The origin of these graben is not yet fully understood, but comparison with numerical models suggests that the majority of such features are the result of stresses from local thermal contraction. In this paper, we highlight a previously unreported category of ghost craters, quantify extensional strains across graben-bearing ghost craters, and make use of graben geometries to gain insights into the subsurface geology of smooth plains areas. In particular, the style and mechanisms of graben development imply that flooding of impact craters and basins led to substantial pooling of lavas, to thicknesses of ∼1.5 km. In addition, surface strains derived from groups of graben are generally in agreement with theoretically and numerically derived strains for thermal contraction

Galactic Globular and Open Clusters in the Sloan Digital Sky Survey. I. Crowded Field Photometry and Cluster Fiducial Sequences in ugriz

We present photometry for globular and open cluster stars observed with the Sloan Digital Sky Survey (SDSS). In order to exploit over 100 million stellar objects with r < 22.5 mag observed by SDSS, we need to understand the characteristics of stars in the SDSS ugriz filters. While star clusters provide important calibration samples for stellar colors, the regions close to globular clusters, where the fraction of field stars is smallest, are too crowded for the standard SDSS photometric pipeline to process. To complement the SDSS imaging survey, we reduce the SDSS imaging data for crowded cluster fields using the DAOPHOT/ALLFRAME suite of programs and present photometry for 17 globular clusters and 3 open clusters in a SDSS value-added catalog. Our photometry and cluster fiducial sequences are on the native SDSS 2.5-meter ugriz photometric system, and the fiducial sequences can be directly applied to the SDSS photometry without relying upon any transformations. Model photometry for red giant branch and main-sequence stars obtained by Girardi et al. cannot be matched simultaneously to fiducial sequences; their colors differ by ~0.02-0.05 mag. Good agreement (< ~0.02 mag in colors) is found with Clem et al. empirical fiducial sequences in u'g'r'i'z' when using the transformation equations in Tucker et al.Comment: 30 pages, 25 figures. Accepted for publication in ApJS. Version with high resolution figures available at http://www.astronomy.ohio-state.edu/~deokkeun/AnJohnson.pd

Ancient heat flow, crustal thickness, and lithospheric mantle rheology in the Amenthes region, Mars

Surface heat flow calculations for the Amenthes region of Mars can be independently performed using the depth to the brittle–ductile transition and the effective elastic thickness of the lithosphere estimated for the Late Noachian/Early Hesperian (equivalent to an estimated absolute age of ~3.6–3.8 Ga). This, along with crustal heat production rates estimated from heat-producing elements abundances, permits us to put constraints, for that particular place and time, on both the thermal and mechanical properties of the lithosphere and the crustal thickness. The depth to the brittle– ductile transition deduced from modeling of the topography of Amenthes Rupes is 27–35 km, and the associated surface heat flow is 26–37 mWm−2. On the other hand, the effective elastic thickness in this region is between 19 and 35 km: the surface heat flow deduced by considering crustal and lithospheric mantle contributions to the total lithospheric strength, as well as wet or dry olivine for lithospheric mantle rheology, is 31–49mWm−2. The relatively limited overlap among Te- andzBDT-based heat flowvalues implies a surface heat flowof 31–36mWm−2 (with a high fraction originated from crustal heat sources) and awet mantle rheology. The so obtained local crustal thickness is 43–74 km,which suggests an average thickness of~40–75 km for the Martian crust; for the frequently used crustal density of 2900 kgm−3, our results suggest a crustal thickness of 50–63km for theAmenthes region, and an average crustal thickness of ~45–65 km for Mars

Analysis of 8-oxo-7,8-dihydro-2′-deoxyguanosine by ultra high pressure liquid chromatography–heat assisted electrospray ionization–tandem mass spectrometry

Increased amounts of reactive oxygen species (ROS), generally termed oxidative stress, are frequently hypothesized to be causally associated with many diseases. Analyses of 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxo-dG) in DNA and urine are widely used biomarkers for oxidative stress. Over the years it became clear that analysis of 8-oxo-dG in DNA is challenging due to artifactual formation during sample work up. The present study demonstrates that 8-oxo-dG can be measured reliably and accurately when appropriate precautions are taken. First, the presence of an antioxidant, metal chelator, or free radical trapping agent during sample preparation improves reproducibility. Second, sample enrichment by HPLC fraction collection was used to optimize sensitivity. Third, heat assisted electrospray ionization (HESI) eliminated potential interferences and improved assay performance and sensitivity. Subsequently, the UPLC–HESI–MS/MS method was applied to show the biphasic dose response of 8-oxo-dG in H2O2-treated HeLa cells. Application of this method to human lymphocyte DNA (n = 156) gave a mean±SD endogenous amount of 1.57±0.88 adducts per 106 dG, a value that is in agreement with the suggested amount previously estimated by European Standard Committee on Oxidative DNA Damage (ESCODD) and others. These results suggest that the present method is well suited for application to molecular toxicology and epidemiology studies investigating the role of oxidative stress

The Distribution and Origin of Smooth Plains on Mercury

Orbital images from the MESSENGER spacecraft show that ~27% of Mercury's surface is covered by smooth plains, the majority (greater than 65%) of which are interpreted to be volcanic in origin. Most smooth plains share the spectral characteristics of Mercury's northern smooth plains, suggesting they also share their magnesian alkali-basalt-like composition. A smaller fraction of smooth plains interpreted to be volcanic in nature have a lower reflectance and shallower spectral slope, suggesting more ultramafic compositions, an inference that implies high temperatures and high degrees of partial melting in magma source regions persisted through most of the duration of smooth plains formation. The knobby and hummocky plains surrounding the Caloris basin, known as Odin-type plains, occupy an additional 2% of Mercury’s surface. The morphology of these plains and their color and stratigraphic relationships suggest that they formed as Caloris ejecta, although such an origin is in conflict with a straightforward interpretation of crater size-frequency distributions. If some fraction is volcanic, this added area would substantially increase the abundance of relatively young effusive deposits inferred to have more mafic compositions. Smooth plains are widespread on Mercury, but they are more heavily concentrated in the north and in the hemisphere surrounding Caloris. No simple relationship between plains distribution and crustal thickness or radioactive element distribution is observed. A likely volcanic origin for some older terrain on Mercury suggests that the uneven distribution of smooth plains may indicate differences in the emplacement age of large-scale volcanic deposits rather than differences in crustal formational process