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In this work, we use models constructed with the Eggleton code for stellar evolution, along with the photometric data of the super-rich globular cluster ω -Centauri (Sollima et al., 2004), to put a constraint on the magnetic dipole moment of neutrinos. We begin with a review of the idea proposed by Raffelt and Dearborn (1988), in which, as a consequence of a non-zero magnetic dipole moment, the tip-RGB luminosity of low mass stars gets increased over its standard value. First, we measure the dependence of the He-core mass and bolometric luminosity, at the tip-RGB, on the existing fits to characterize plasmon decay into neutrinos, namely those from Itoh et al. (1992), Haft et al. (1994), and the more recent results from Kantor and Gushakov (2007). Then, stating our definition of the tip-RGB, we revise multiple theoretical aspects: the consequences of non-standard neutrino emission on the internal structure of stellar models, its impact on the calibration of the Reimers mass-loss rate and later evolutionary phases and the influence of initial Helium abundance, metallicity, convection theory and opacities. Finally, we consider the specific case of ω -Cen. Using our tip-RGB models, and the bolometric correction obtained by the PHOENIX code for stellar atmospheres, to estimate the luminosity for canonical and non-standard evolution, also measuring the impact of the reported chemical spread in ω -Cen on our results. We find that the upper limit μ ν ≤ 2.2 × 10 - 12 μ B is already well constrained by observations. This result compares with the one obtained by Viaux et al. (2013), μ ν ≤ 2.6 × 10 - 12 μ B , from photometric study of the globular cluster M5.

We obtained a time series of spectra covering the secondary maximum in the I-band of the bright Type Ia supernova 2014J in M82 with the TIGRE telescope. Comparing the observations with theoretical models calculated with the time dependent extension of the PHOENIX code, we identify the feature that causes the secondary maximum in the I-band light curve. Fe II 3d6(3D)4s-3d6(5D)4p and similar high excitation transitions produce a blended feature at 7500 {\AA}, which causes the rise of the light curve towards the secondary maximum. The series of observed spectra of SN 2014J and archival data of SN 2011fe confirm this conclusion. We further studied the plateau phase of the Rband light curve of SN 2014J and searched for features which contribute to the flux. The theoretical models do not clearly indicate a new feature that may cause the Rband plateau phase. However, Co II features in the range of 6500 - 7000 {\AA} and the Fe II feature of the I-band are clearly seen in the theoretical spectra, but do not appear to provide all of the flux necessary for the R-band plateau., Comment: 7 pages, 8 figures, accepted for publication in MNRAS

PROBLEM/CONDITION Suicide is a public health problem and one of the top 10 leading causes of death in the United States. Substantial geographic variations in suicide rates exist, with suicides in rural areas occurring at much higher rates than those occurring in more urban areas. Understanding demographic trends and mechanisms of death among and within urbanization levels is important to developing and targeting future prevention efforts. REPORTING PERIOD 2001-2015. DESCRIPTION OF SYSTEM Mortality data from the National Vital Statistics System (NVSS) include demographic, geographic, and cause of death information derived from death certificates filed in the 50 states and the District of Columbia. NVSS was used to identify suicide deaths, defined by International Classification of Diseases, 10th Revision (ICD-10) underlying cause of death codes X60-X84, Y87.0, and U03. This report examines annual county level trends in suicide rates during 2001-2015 among and within urbanization levels by select demographics and mechanisms of death. Counties were collapsed into three urbanization levels using the 2006 National Center for Health Statistics classification scheme. RESULTS Suicide rates increased across the three urbanization levels, with higher rates in nonmetropolitan/rural counties than in medium/small or large metropolitan counties. Each urbanization level experienced substantial annual rate changes at different times during the study period. Across urbanization levels, suicide rates were consistently highest for men and non-Hispanic American Indian/Alaska Natives compared with rates for women and other racial/ethnic groups; however, rates were highest for non-Hispanic whites in more metropolitan counties. Trends indicate that suicide rates for non-Hispanic blacks were lowest in nonmetropolitan/rural counties and highest in more urban counties. Increases in suicide rates occurred for all age groups across urbanization levels, with the highest rates for persons aged 35-64 years. For mechanism of death, greater increases in rates of suicide by firearms and hanging/suffocation occurred across all urbanization levels; rates of suicide by firearms in nonmetropolitan/rural counties were almost two times that of rates in larger metropolitan counties. INTERPRETATION Suicide rates in nonmetropolitan/rural counties are consistently higher than suicide rates in metropolitan counties. These trends also are observed by sex, race/ethnicity, age group, and mechanism of death. PUBLIC HEALTH ACTION Interventions to prevent suicides should be ongoing, particularly in rural areas. Comprehensive suicide prevention efforts might include leveraging protective factors and providing innovative prevention strategies that increase access to health care and mental health care in rural communities. In addition, distribution of socioeconomic factors varies in different communities and needs to be better understood in the context of suicide prevention.

Homicide is one of the leading causes of death for women aged ≤44 years.* In 2015, homicide caused the death of 3,519 girls and women in the United States. Rates of female homicide vary by race/ethnicity (1), and nearly half of victims are killed by a current or former male intimate partner (2). To inform homicide and intimate partner violence (IPV) prevention efforts, CDC analyzed homicide data from the National Violent Death Reporting System (NVDRS) among 10,018 women aged ≥18 years in 18 states during 2003-2014. The frequency of homicide by race/ethnicity and precipitating circumstances of homicides associated with and without IPV were examined. Non-Hispanic black and American Indian/Alaska Native women experienced the highest rates of homicide (4.4 and 4.3 per 100,000 population, respectively). Over half of all homicides (55.3%) were IPV-related; 11.2% of victims of IPV-related homicide experienced some form of violence in the month preceding their deaths, and argument and jealousy were common precipitating circumstances. Targeted IPV prevention programs for populations at disproportionate risk and enhanced access to intervention services for persons experiencing IPV are needed to reduce homicides among women.

We present the solar S-index record of cycle 24, obtained by the TIGRE robotic telescope facility and its high-resolution spectrograph HEROS (R$\approx$20,000), which measures the solar chromospheric Ca II H&K line emission by using moonlight. Our calibration process uses the same set of standard stars as introduced by the Mt. Wilson team, thus giving us a direct comparison with their huge body of observations taken between 1966 and 1992, as well as with other cool stars. Carrington cycle 24 activity started from the unusually deep and long minimum 2008/09, with an S-index average of only 0.154, by 0.015 deeper than the one of 1986 (=0.169). In this respect,the chromospheric radiative losses differ remarkably from the variation of the coronal radio flux F10.7cm and the sunspot numbers. In addition, the cycle 24 S-amplitude remained small, 0.022 (cycles 21 and 22 averaged: 0.024), and so resulted a very low 2014 maximum of =0.176 (cycles 21 and 22 averaged: 0.193). We argue that this find is significant, since the Ca II H&K line emission is a good proxy for the solar far-UV flux, which plays an important role in the heating of the Earth's stratosphere, and we further argue that the solar far-UV flux changes change s with solar activity much more strongly than the total solar output., 8 pages, 12 figure, accepted by MNRAS

We present results of our dense spectroscopic monitoring of Nova V5668 Sgr. Starting on March 19 in 2015, only a few days after discovery, we have obtained a series of spectra with the TIGRE telescope and its HEROS echelle spectrograph which offers a resolution of R = 20,000 and covers the optical wavelength range from 3800 to 8800 {\AA}. We performed a line identification of the discernible features for four spectra which are representative for the respective phases in the light curve evolution of that nova. By simultaneously analysing the variations in the visual light curve and the corresponding spectra of Nova V5668 Sgr, we found that during the declining phases of the nova the absorption features in all hydrogen and many other lines had shifted to higher expansion velocities of -2000 km s^-1. Conversely, during the rise towards the following maximum, these observed absorption features had returned to lower expansion velocities.We found that the absorption features of some Fe II lines displayed the same behaviour, but in addition disappeared for a few days during some declining phases. Features of several N I lines also disappeared while new N II lines appeared in emission for a few days during some of the declining phases of the light curve of Nova V5668 Sgr. The shape of the emission features is changing during the evolution and shows a clear double peak structure after the deep minimum., Comment: 13 pages, 11 figures, accepted for publication in AN

We explore the general astrobiological significance of F-type main-sequence stars with masses between 1.2 and 1.5 Msun. Special consideration is given to stellar evolutionary aspects due to nuclear main-sequence evolution. DNA is taken as a proxy for carbon-based macromolecules following the paradigm that extraterrestrial biology may be most likely based on hydrocarbons. Consequently, the DNA action spectrum is utilized to represent the impact of the stellar UV radiation. Planetary atmospheric attenuation is taken into account based on parameterized attenuation functions. We found that the damage inflicted on DNA for planets at Earth-equivalent positions is between a factor of 2.5 and 7.1 higher than for solar-like stars, and there are intricate relations for the time-dependence of damage during stellar main-sequence evolution. If attenuation is considered, smaller factors of damage are obtained in alignment to the attenuation parameters. This work is motivated by earlier studies indicating that the UV environment of solar-type stars is one of the most decisive factors in determining the suitability of exosolar planets and exomoons for biological evolution and sustainability., 37 pages, 12 figures, 4 tables; International Journal of Astrobiology (in press)

The role of computational mathematics on the study of the fundamental properties of neutrinos and axions and their impact on the energy loss within stellar structure is illustrated in this work. The theoretical predictions, done with the aid of a numerical code for simulating stellar evolution, are used in three cases of interest: the number of neutrinos reaching our planet from the closest stellar system, calculated by modelling its two main stars and their corresponding neutrino spectrum; the magnitude of the neutrino magnetic dipole moment and the axion-electron coupling constant is estimated by comparing stellar models to the tip-RGB of fifty globular clusters; and, finally, the survival of the Earth, after the Sun becomes a red giant is tested for an scenario in which axions and neutrinos are being simultaneously produced within the solar core.

Offers guidelines to aid school officials in planning school construction projects and choosing an architect. (JG)

Socio-political forecasting, a new dimension to university planning that can provide universities time to prepare for the impact of social and political changes, is examined. The four elements in the process are scenarios of the future, the probability/diffusion matrix, the profile of significant value-system changes, and integration and application. (JMD)

The effect of carbon nanotube (CNT) integration in polymer matrixes (two-phase) and fibre reinforced composites (three-phase) was studied. Simulations for CNT/polymer composites (nanocomposites) and CNT/fibre/polymer composites (multiscale) were carried out by combining micromechanical theories applied to nanoscale and woven fibre micromechanic theories. The mechanical properties (Young’s modulus, Poisson’s ratio and shear modulus) of a multiscale composite were predicted. The relationships between the mechanical properties of nano- and multiscale composite systems for various CNT aspect ratios were studied. A comparison was made between a multiscale system with CNTs infused throughout and one with nanotubes excluded from the fabric tows. The mechanical properties of the composites improved with increased CNT loading. The influence of CNT aspect ratio on the mechanical properties was more pronounced in the nanocomposites than in the multiscale composites. Composites with CNTs in the fibre strands ...

Multiwalled carbon nanotube (MWNT) reinforced epoxy resin composites were fabricated and characterised. Several process variables were investigated using design of experiments. The MWNTs (0·5 wt-%) were dispersed in Epon 862 epoxy resin under various sonication conditions. Young’s modulus, energy to failure, glass transition temperature Tg and storage modulus E′ were assessed. The first three were selected in a design of experiment optimisation study. The results indicated that as the sonication intensity and the duration of sonication were increased, the material response of the MWNT/epoxy composite, specifically Young’s modulus, energy and Tg, was enhanced. The fracture surfaces of the composites were examined using scanning electron microscopy. Improved dispersion was observed in samples fabricated with increased sonication intensities. The Mori–Tanaka model was used to predict the mechanical properties of the MWNT/epoxy composites and was found to be in reasonable agreement with experimental d...

Summary 1. Despite non-point-source (NPS) pollution being perhaps the most ubiquitous stressor affecting urban streams, there is a lack of research assessing how urban NPS pollution affects stream ecosystems. We used a natural experimental design approach to assess how stream macroinvertebrate community structure, secondary production and trophic structure are influenced by urban NPS pollution in six streams. 2. Differences in macroinvertebrate community structure and secondary production among sites were highly correlated with stream-water specific conductivity and dissolved inorganic phosphorus (DIP) concentrations. Macroinvertebrate richness, the Shannon diversity index and the Shannon evenness index were all negatively correlated with specific conductivity. These patterns were driven by differences in the richness and production of EPT and other intolerant taxa. Production of the five most productive taxa, tolerant taxa, non-insect taxa and primary consumers were all positively correlated with stream-water DIP. 3. Despite the positive correlation between primary consumer production and DIP, there was no correlation between macroinvertebrate predator production and either total or primary consumer macroinvertebrate production. This was observed because DIP was positively correlated with the production of non-insect macroinvertebrate taxa assumed to be relatively unavailable for macroinvertebrate predator consumption. After removing production of these taxa, we observed a strong positive correlation between macroinvertebrate predator production and production of available prey. 4. Our results suggest that urban NPS pollution not only affects macroinvertebrate community structure, but also alters secondary production and trophic-level dynamics. Differences in taxon production in our study indicate the potential for altered energy flow through stream food webs and potential effects on subsidies of aquatic insect prey to riparian food webs.

PROBLEM/CONDITION In 2013, more than 57,000 persons died in the United States as a result of violence-related injuries. This report summarizes data from CDC's National Violent Death Reporting System (NVDRS) regarding violent deaths from 17 U.S. states for 2013. Results are reported by sex, age group, race/ethnicity, marital status, location of injury, method of injury, circumstances of injury, and other selected characteristics. REPORTING PERIOD COVERED 2013. DESCRIPTION OF SYSTEM NVDRS collects data from participating states regarding violent deaths obtained from death certificates, coroner/medical examiner reports, law enforcement reports, and secondary sources (e.g., child fatality review team data, supplemental homicide reports, hospital data, and crime laboratory data). This report includes data from 17 states that collected statewide data for 2013 (Alaska, Colorado, Georgia, Kentucky, Maryland, Massachusetts, North Carolina, New Jersey, New Mexico, Ohio, Oklahoma, Oregon, Rhode Island, South Carolina, Utah, Virginia, and Wisconsin). NVDRS collates documents for each death and links deaths that are related (e.g., multiple homicides, a homicide followed by a suicide, or multiple suicides) from a single incident. RESULTS For 2013, a total of 18,765 fatal incidents involving 19,251 deaths were captured by NVDRS in the 17 states included in this report. The majority (66.2%) of deaths were suicides, followed by homicides (23.2%), deaths of undetermined intent (8.8%), deaths involving legal intervention (1.2%) (i.e., deaths caused by law enforcement and other persons with legal authority to use deadly force, excluding legal executions), and unintentional firearm deaths (

Seasonal changes in macroinvertebrate taxon abundances that are related to life history introduce temporal variation into macroinvertebrate community structure that can potentially confound bioassessments. In this study, macroinvertebrates from three rural and three urban streams were sampled monthly to assess temporal variability in community structure, determine how taxon life-cycle seasonality affects this variability, and determine if this temporal variability confounds biotic index interpretations. Temporal variation in taxon abundances was higher in the rural streams than in the urban streams, and 17 of 23 indicator taxa from rural streams exhibited, or are known to exhibit, either fast- or slow-seasonal life cycles. Conversely, five taxa were identified as indicators for urban streams, but only two of these taxa exhibited seasonal life cycles. Further, the life-cycle seasonality of many rural stream indicator taxa appeared to be linked to the seasonality of environmental conditions such as hydrologic permanence and benthic leaf detritus availability. Macroinvertebrate bioassessment index (MBI) scores were higher in the rural streams than in the urban streams during all months except June, July, and October when no difference was detected. We attribute the reduced discriminatory power of the MBI in the summer and early autumn to the life-cycle of a single taxon ( Stenelmis sp.), and its effects on % Clingers – a component metric of the MBI. Stenelmis sp. exhibited a non-seasonal life cycle with a larval development time of approximately 12 months with considerable overlapping of cohorts present during the summer and early autumn when an extended first instar recruitment period was evident. During this overlap period, urban stream MBI values increased resulting in no statistical difference in the MBI between urban and rural streams in June, July, and October. Analyses of temporal variability in taxon abundances and life-history characteristics, as completed in this study, can greatly contribute to the creation and/or validation of bioassessment protocols.

Objective To describe the National Violent Death Reporting System (NVDRS). This is a surveillance system for monitoring the occurrence of homicides, suicides, unintentional firearm deaths, deaths of undetermined intent, and deaths from legal intervention (excluding legal executions) in the US. Design This report provides information about the history, scope, data variables, processes, utility, limitations, and future directions of the NVDRS. Results The NVDRS currently operates in 32 states, with the goal of future expansion to all 50 states, the District of Columbia, and US territories. The system uses existing primary data sources (death certificates, coroner/medical examiner reports, and law enforcement reports), and links them together to provide a comprehensive picture of the circumstances surrounding violent deaths. Conclusions This report provides an overview of the NVDRS including a description of the system, discussion of its expanded capability, the use of new technologies as the system has evolved, how the data are being used for violence prevention efforts, and future directions.

The T box antiterminator RNA element is an important component of the T box riboswitch that controls the transcription of vital genes in many Gram-positive bacteria. A series of 1,4-disubstituted 1,2,3-triazoles was screened in a fluorescence-monitored thermal denaturation assay to identify ligands that altered the stability of antiterminator model RNA. Several ligands were identified that significantly increased or decreased the melting temperature (Tm) of the RNA. The results indicate that this series of triazole ligands can alter the stability of antiterminator model RNA in a structure-dependent manner.

This research presents an experimental and theoretical investigation on the effects of carbon nanotube (CNT) integration within neat epoxy resin (nanocomposites) and a carbon fabric–epoxy composite (multiscale composites). An approach is presented for the prediction of mechanical properties of multiscale composites. This approach combines woven fibre micromechanics (MESOTEX) with the Mori-Tanaka model which was used for the prediction of mechanical properties of nanocomposites in this research. Nanocomposite and multiscale composite samples were manufactured using cast moulding, resin infusion, and hand lay-up process. The CNT concentrations in the composite samples were from 0 to 5 wt-%. The samples were characterised using tensile, shear and flexural tests. The discrepancy between the theoretical predictions and the experimental observations was hypothesised to be due to dispersion and bonding issues and SEM images are presented in support of the hypothesis.

Mountaintop removal and valley fill (MTR/VF) coal mining has altered the landscape of the Central Appalachian region in the USA. Among the changes are large-scale topographic recontouring, burial of headwater streams, and degradation of downstream water quality. The goals of our study were to: 1) compare the structure and function of natural and constructed stream channels in forested and MTR/VF catchments across ephemeral, intermittent, and perennial flow regimes and 2) assess the relationship between leaf litter breakdown and structural measures, such as the habitat assessments currently used by regulatory agencies. Specific conductance of stream water was, on average, 36 to 57× higher at perennial reaches below valley fills than at perennial reaches in forested catchments, whereas pH was circumneutral in both catchment types. Channel habitat and invertebrate assemblages in litter bags differed between forested streams and constructed channels in VF catchments. Invertebrate density, diversity, a...

The decay rate of cellulose filters and associated chemical and biological characteristics were compared with those of white oak (Quercus alba) leaves to determine whether cellulose filters could be a suitable standardized material for assessing deciduous leaf breakdown in headwater streams. The comparison was done across reaches draining mixed deciduous forest and post-coal mining catchments, in natural and constructed channels, and ranged in flow duration from ephemeral to perennial. Decay rates of leaves and filters were predicted to differ at a given site, but the decay rates and associated characteristics of leaf and filter litterbags would be positively related. Filter decay rates did not differ across channel type or flow permanence class. Oak leaves decayed ca 2·5× faster than cellulose filters and there was no relationship between decay rates (R2 = 0·02). Ergosterol concentration, total invertebrate density, shredder density, total invertebrate biomass and taxa richness were significantly higher in oak litterbags than in filter litterbags across four sampling dates over 306 days. The biomass of invertebrate shredders colonizing litterbags did not differ between the substrate types. The C:N content was higher for filters than for oak leaves, but the mean difference between substrates decreased by ∼10-fold over the 306-day study. In contrast, mean differences in ergosterol concentration between substrates increased threefold over the study. Although characteristics associated with filter litterbags were positively related to those of oak leaf litterbags, most relationships had low explanatory power (R2⩽0·3); however, stronger relationships existed for total invertebrate density, shredder density and taxa richness (R2 = 0·78). Although a standardized material would be useful for incorporating litter breakdown in stream assessments, because of the strong differences in decay rate and associated characteristics, we cannot recommend cellulose filters as a suitable substrate to represent the natural breakdown of leaf material. Published in 2010. This article is a US Government work and is in the public domain in the USA.

The role of hematopoietic cytokines in lineage commitment remains uncertain. To gain insight into the contribution of cytokine signaling to myeloid lineage specification, we compared granulocyte colony-stimulating factor (G-CSF) and macrophage colony-stimulating factor (M-CSF) signaling in Ba/F3 cells expressing both the G-CSF and M-CSF receptors and in lineage-negative murine marrow cells. G-CSF and M-CSF serve as prototypes for additional cytokines that also influence immature myeloid cells. G-CSF specifically activated signal transducer and activator of transcription 3 and induced Src homology region 2 domain-containing phosphatase 2 (SHP2) phosphorylation, whereas M-CSF preferentially activated phospholipase Cγ2, and thereby extracellular signal-regulated kinase (ERK), to stabilize c-Fos and stimulate CCAAT/enhancer-binding protein (C/EBP)α(S21) phosphorylation. In contrast, activation of Jun kinase or c-Jun was similar in response to either cytokine. Inhibition of ERK prevented induction of c-Fos by M-CSF and reduced C/EBPα phosphorylation and formation of colony-forming unit–monocytes. SHP2 inhibition reduced ERK activation in G-CSF, but not M-CSF, and reduced colony-forming unit–granulocytes, underscoring divergent pathways to ERK activation. Phorbol ester mimicked the effect of M-CSF, activating ERK independent of SHP2. In summary, M-CSF activates ERK more potently than G-CSF, and thereby induces higher levels of c-Fos and phospho-C/EBPα(S21), which may directly interact to favor monopoiesis, whereas G-CSF activates signal transducer and activator of transcription 3 and SHP2, potentially shifting the balance to granulopoiesis via gene induction by C/EBPα homodimers and via effects of SHP2 on regulators besides ERK.

W. Reid Hastie, the fifth president (1957-1959) of the National Art Education Association, promoted the need for a scholarly venue devoted entirely to issues and research in art education and a place where related research results could be presented on a regular basis to the field of art education, as well as the larger field of education. His vision led to the initiation of Studies in Art Education, a journal of issues and research in art education. The first issue was published in the Fall of 1959. Hasties vision, practice, and support of research are examined within the context of the history of research in art education and the rapidly changing world of higher education following World War II.When Studies in Art Education was introduced to the field of art education in 1959 as a journal for professional and critical dialogue about issues and research related to art and art education, it was a landmark. For die first time ever, there was a scholarly venue devoted entirely to issues and research related to art education. The fact that it has survived and flourished is a testament to the vision of W. Reid Hastie, the National Art Education Association (NAEA) president (1957-1959) under whose leadership Studies in Art Education was established. It is also a testament to the need for a forum where art education researchers could share the results of their work and engage in a dialogue with professional colleagues throughout the world (Beelke, 1972).Research Trends in Art EducationWhile there is an established history of research in art education predating the beginning of Studies, most related research prior to 1 940 was conducted by individuals outside the discipline. Those few individuals, both art educators and non-art educators, who published their work did so in a variety of educational, psychological, and sociological journals (Davis, 1967). The earliest known piece of published research with a relationship to art education was a study conducted by the legendary leader of the child study movement, G. Stanley Hall. In May of 1883, he published a report on a study of the contents of children's minds on entering schools in the Princeton Review (Hall, 1883).In her thesis, A Summary ofScientific Investigations Relatingto Art, Mary Strange (1940) presented a systematic look at scientific research in art and art education prior to that time, identifying all published research that she could locate. She reported that during the 57-year period between 1883 and 1939, 162 studies were published in books and in a wide variety of educational and psychological journals such as Pedagogical Seminary, American Journal ofPsychohgy, and the British Journal of Psychology. These publications grouped themselves into four general categories: (a) color and color vision, (b) drawing and/or graphic ability, (c) picture preference and appreciation, and (d) tests and measurements. An examination of this work reveals that most of it was conducted by individuals outside the field of art education, primarily by psychologists and sociologists. In many cases, it appears that art was being used as a means to an end, without any foundational basis in aesthetics, creativity, or artistic processes (Davis, 1967). For example, the focus of many of the studies was not on art but on other topics such as mental development, intelligence, special talents and defects, differences in males and females on various traits, and school success. Art was simply used as a vehicle to examine the phenomenon being investigated.Following World War II, the United States experienced unprecedented growth in higher education with the returning veterans and support of their education by the G.I. Bill. Art education was not excluded, and educational opportunities in die field were characterized by phenomenal growth, especially at the graduate level. More researchers who were art educators emetged, bringing about more research in art education. The field of art education was developing to a point that more research was necessary if continued growth were to occur. …

Aims. We present first results and tests of a time-dependent extension to the general purpose model atmosphere code PHOENIX. We aim to produce light curves and spectra of hydro models for all types of supernovae. Methods. We extend our model atmosphere code PHOENIX to solve time-dependent non-grey, NLTE, radiative transfer in a special relativistic framework. A simple hydrodynamics solver was implemented to keep track of the energy conservation of the atmosphere during free expansion. Results. The correct operation of the new additions to PHOENIX were verified in test calculations. Conclusions. We have shown the correct operation of our extension to time-dependent radiative transfer and will be able to calculate supernova light curves and spectra in future work., 7 pages, 12 figures

Daphnia lumholtzi has been very successful in colonizing North America since its appearance in Texas in 1990. Although previous studies have sought to link its success as an invasive species with various aspects of its population biology, there is little experimental data linking the invasion success of D. lumholtzi with its autecology, specifically its reproduction strategy. In this study we sought to link food quality and quantity to diapause in D. lumholtzi through a variation in phosphorus (P) content of algae, food quantity, and light level. We also assessed the effect of Daphnia peak population densities on reproductive rates and production of resting eggs. We found that when food is abundant, per capita ephippia production may be limited by P, but under food limitation conditions, there is no significant effect of food quality on ephippia production. Our results suggest that a combination of food quality/quantity and population density may work together to induce the production of resting eggs in this invasive species.

T box bacterial genes utilize a riboswitch mechanism to regulate gene expression at the transcriptional level. Complementary base pairing of the 5′-untranslated mRNA with uncharged cognate tRNA stabilizes formation of an antiterminator element and permits complete transcription. In the absence of tRNA, a mutually exclusive RNA terminator element forms and results in transcription termination. This regulatory mechanism requires divalent metal ions at the antitermination event. The structural effects of Mg2+ binding to antiterminator model RNA were investigated to ascertain if this requirement is due to the presence of a specific metal ion binding site in the antiterminator. Spectroscopic analysis identified the presence of a hydrated, diffuse Mg2+ binding site. The results indicate that the mechanistic requirement for divalent metal ions is not due to Mg2+-induced pre-formation of a functional antiterminator receptor; rather, Mg2+ binds in a helical region of high phylogenetic sequence conservation adjacent to the tRNA binding site.