192 research outputs found
Master of Arts
thesisRecent controversy en the nation's college campuses has focused the attention of the American people on the Reserve Officers Training Program and the role it plays in providing commissioned officers for the armed forces of the United States. Caught up in the midst of this controversy is the AROTC Instructor whose presence on the University campus is not only being questioned, but also the position he occupies and the recognition he receives. It was the purpose of this study to examine the AROTC Instructor at the University of Utah, his selection and assignment to the faculty, and the response of the students at the University to the instruction lr/hich they received. A review of both official military publications and unofficial sources provided the information concerning the selection and assignment of Army officers as instructors in the AROTe program. Student response was measured by extracting the results of student course evaluations, student opinion polls, and official University studies as they related to this study. Additional information concerning the instructor traits of the AROTC instructors was obtained by evaluating them on the basis of a list of traits developed to form an image for the "Ideal" instructor
Laboratory course on Streptomyces genetics and secondary metabolism
The "Streptomyces genetics and secondary metabolism" laboratory course gives an introduction to the versatile soil dwelling Gram-positive bacteria Streptomyces and their secondary metabolism. The course combines genetic modification of Streptomyces; growing of the strain and protoplast preparation, plasmid isolation by alkaline lysis and phenol precipitation, digestions, and ligations prior to protoplast transformation, as well as investigating the secondary metabolites produced by the strains. Thus, the course is a combination of microbiology, molecular biology, and chemistry. After the course the students should understand the relationship between genes, proteins, and the produced metabolites. 2016 by The International Union of Biochemistry and Molecular Biology, 44(5):492-499, 2016. 2016 The International Union of Biochemistry and Molecular Biology.</p
Can models for forest attributes based on airborne laser scanning be generalized for different silvicultural management systems?
In Finland, interest in continuous cover forestry (CCF) has increased rapidly in recent years. During those years CCF has been examined from various viewpoints but not from the perspective of forest inventories. This holds especially true for applications based on remote sensing. Conversely, airborne laser scanning (ALS) data have been widely used to predict forest characteristics such as size distribution and vertical forest structure, which are closely related to the forest information needs of CCF. In this study we used the area-based approach to predict a set of stand attributes from ALS data (5 pulses per m2) in a CCF forest management experiment in Katajama & BULL;ki, eastern Finland. In addition to the CCF stands, the experiment included shelterwood stands and untreated stands. The predicted attributes included volume, biomass, basal area, number of stems, mean diameter, Lorey's height, dominant height, standing dead wood volume, parameters of the theoretical stem diameter distribution model, understory height and number of understory stems. Our main aim was to test whether the same model could be used across different management systems. The accuracy of the attributes predicted for the CCF stands was compared with the predictions for the other management systems in the same experiment. We also compared and discussed our results in relation to the even-aged stand attribute predictions that were conducted by using separate operational forest data collected from sites surrounding Katajama & BULL;ki. The results showed that forest data from the different management systems could be combined into a single model of a stand attribute, i.e., ALS metrics were found to be suitable for comparing different management systems in regard to differences in forest structure. The accuracy of the predicted attributes in the CCF plots was comparable to that of the other management alternatives in the experiment. The accuracy was also comparable to that of even-aged forests. The results of this study were promising; the stand attributes of CCF-managed forests could be predicted analogously to those of other management systems. This indicates that for the purposes of forest inventories there may not be a need to stratify forest lands by management system. It should be noted, however, that the study area was relatively small, that the forest stands were harvested in the 1980 s, and that the attributes may not have been completely exhaustive for CCF
Transparent dense sodium
Under pressure, metals exhibit increasingly shorter interatomic distances.
Intuitively, this response is expected to be accompanied by an increase in the
widths of the valence and conduction bands and hence a more pronounced
free-electron-like behaviour. But at the densities that can now be achieved
experimentally, compression can be so substantial that core electrons overlap.
This effect dramatically alters electronic properties from those typically
associated with simple free-electron metals such as lithium and sodium, leading
in turn to structurally complex phases and superconductivity with a high
critical temperature. But the most intriguing prediction - that the seemingly
simple metals Li and Na will transform under pressure into insulating states,
owing to pairing of alkali atoms - has yet to be experimentally confirmed. Here
we report experimental observations of a pressure-induced transformation of Na
into an optically transparent phase at 200 GPa (corresponding to 5.0-fold
compression). Experimental and computational data identify the new phase as a
wide bandgap dielectric with a six-coordinated, highly distorted
double-hexagonal close-packed structure. We attribute the emergence of this
dense insulating state not to atom pairing, but to p-d hybridizations of
valence electrons and their repulsion by core electrons into the lattice
interstices. We expect that such insulating states may also form in other
elements and compounds when compression is sufficiently strong that atomic
cores start to overlap strongly.Comment: Published in Nature 458, 182-185 (2009
Spatially-resolved electronic and vibronic properties of single diamondoid molecules
Diamondoids are a unique form of carbon nanostructure best described as
hydrogen-terminated diamond molecules. Their diamond-cage structures and
tetrahedral sp3 hybrid bonding create new possibilities for tuning electronic
band gaps, optical properties, thermal transport, and mechanical strength at
the nanoscale. The recently-discovered higher diamondoids (each containing more
than three diamond cells) have thus generated much excitement in regards to
their potential versatility as nanoscale devices. Despite this excitement,
however, very little is known about the properties of isolated diamondoids on
metal surfaces, a very relevant system for molecular electronics. Here we
report the first molecular scale study of individual tetramantane diamondoids
on Au(111) using scanning tunneling microscopy and spectroscopy. We find that
both the diamondoid electronic structure and electron-vibrational coupling
exhibit unique spatial distributions characterized by pronounced line nodes
across the molecular surfaces. Ab-initio pseudopotential density functional
calculations reveal that the observed dominant electronic and vibronic
properties of diamondoids are determined by surface hydrogen terminations, a
feature having important implications for designing diamondoid-based molecular
devices.Comment: 16 pages, 4 figures. to appear in Nature Material
The scattering and extinction properties of nanodiamonds
The study of scattering and extinction properties of possible nanodiamond
grains in the ISM are reported. Calculations using Discrete Dipole
Approximation (DDA) for varying ellipsoidal shapes and sizes from 2.5 to are considered. Nanodiamonds show negligible extinction from IR to near-UV
and very sharp far-UV rise. Comparison with observations rule out possibility
of independent nanodiamond dust but point towards possibility of nanodiamonds
as a component in the ISM. Radiation induced transformations may lead to
carbonaceous grains with different core and mantles. So calculations are also
performed for a core-mantle target model with nanodiamond core in graphite
mantles. The graphite extinction features get modified with the peak at 2175
\AA{} being lowered, broadened, blue shifted and accompanied by enhanced
extinction in the far-UV. Such variations in the 2175 \AA{} band and
simultaneous far-UV rise are observed along some sources. A three component
dust model incorporating silicate, graphite and graphite with nanodiamond core
is also considered. The model extinction compares very well with the average
galactic extinction in the complete range from 0.2 to . The best
fit requires small size and small number of nanodiamonds.Comment: Accepted for publication in MNRAS; 8 Figure
Strong-correlation effects in Born effective charges
Large values of Born effective charges are generally considered as reliable
indicators of the genuine tendency of an insulator towards ferroelectric
instability. However, these quantities can be very much influenced by strong
electron correlation and metallic behavior, which are not exclusive properties
of ferroelectric materials. In this paper we compare the Born effective charges
of some prototypical ferroelectrics with those of magnetic, non-ferroelectric
compounds using a novel, self-interaction free methodology that improves on the
local-density approximation description of the electronic properties. We show
that the inclusion of strong-correlation effects systermatically reduces the
size of the Born effective charges and the electron localization lengths.
Furthermore we give an interpretation of the Born effective charges in terms of
band energy structure and orbital occupations which can be used as a guideline
to rationalize their values in the general case.Comment: 10 pages, 4 postscript figure
Assessing the benefits and usefulness of Schwartz Centre Rounds in Second-Year Medical Students using Clinical Educator-Facilitated Group Work Session: not just “A Facilitated Moan”!
Background
An experiential curriculum exposing medical students to the clinic early has many benefits but comes with the emotional stress this environment engenders. Schwartz rounds (SR) are an effective means to combat emotional stress and increasingly used in UK and USA hospitals. Recent studies show that the SR format may also provide benefits for medical students. This study aimed to investigate whether the guidance of SR in second year medical students provides the same benefits as to healthcare professionals.
Methods
SR assessment involved 83 second year MBChB students in facilitated groupwork sessions. Topics discussed were “change and resilience” and “duty of candour”. Students completed a Likert Scale questionnaire evaluating outcomes proffered by the Point of Care Foundation in collaboration with the Schwartz Foundation, with freeform feedback.
Results
There was an 86% completion rate with 25% providing written feedback. Participants were more likely to agree than disagree that SR were beneficial. SR effectiveness in enhancing students’ working relationship awareness and skills was strongly correlated with understanding the purpose of, and engagement with, the SR (P<0.001). Similarly, engagement with the SR was strongly correlated with self-reporting of enhanced patient-centredness (P < 0.001). Freeform feedback could be grouped into five themes that revolved around understanding of the SR and engagement with the process. Many positive comments regarded the SR as a forum not only to “learn experientially” but to so in a “safe environment”. Many negative comments stemmed from students not seeing any benefits of engagement with the SR, in that sharing experiences was “unbeneficial”, “empathy is inherent and not learnt”, or that sharing emotional problems is simply “moaning”.
Conclusion
SRs are an effective way of fostering empathy and understanding towards patients and colleagues. However, for the students to benefit fully from the SR it is necessary for them to engage and understand the process. Therefore, for the successful implementation of SR into pre-clinical medical education, it is important to help students realise that SR are not merely a “facilitated whinge”
The Effect of Treating Bacterial Vaginosis on Preterm Labor
Objective: Multiple studies suggest that bacterial vaginosis (BV) causes preterm labor; yet its routine treatment remains controversial. In order to help to elucidate this controversy, we performed a thorough review of studies with levels of evidence ranging from I to II–II. Methods: We searched for all of the studies from the years 1994 to 2001 via Medline’s database, including MD Consult and Ovid Mednet. Results: Several trials discovered a decrease in the incidence of preterm labor when BV was treated, but most of those trials were performed on women with a history of preterm labor. However, the majority of trials reviewed advise against treatment of a general low-risk obstetric population, as there was no significant decrease in preterm labor. Conclusions: Therefore, based on the above studies and the current guidelines of the Centers for Disease Control and Prevention (CDC), treating pregnant women in high-risk populations who are diagnosed with BV provides the clinician with an opportunity to possibly prevent preterm labor in this population. In nulliparous women without a history of preterm birth, treatment is recommended if other risk factors are present (e.g. gonorrhea or chlamydia). However, in the general low-risk populations, routine screening is not indicated
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