674 research outputs found
Ultraviolet cometary spectrophotometry
During the 13 shifts dedicated to observations of Comet Bradfield (including the two European shifts), five high dispersion exposures were obtained with the LWR camera, 27 low dispersion images with the LWR camera, and 36 low dispersion images with the SWP camera of which 5 were observations of the geocoronal background and 4 were taken in a serendipity mode while the nucleus of the comet was centered on the large aperture of the LWR camera
Correlated Ground-based and IUE Observations
The value of coordination among different observers particularly, those working in different wavelength regions is highlighted. This coordination is more important among observers of comets than among observers of almost any other class of astronomical object. The basic reason for this is that comets are highly time-variable, often erratically so, and observations of a particular comet usually cannot be repeated. As a result, some uncoordinated observations cannot be interpreted at all while others are susceptible to misinterpretation. Several specific examples of coordinated observations are discussed
Ground-based photometry of comets in the spectral interval 3000 to 3500 angstrom
Abundances and production rates of CN, C3, and C2 for fifteen comets were determined and the variation of these parameters with helicentric distance for two comets were monitored. While these measurements provide much information about the similarities and differences among comets, only a small fraction of the total material in any of the comets observed was sampled
The 13 November 1984 occultation of BD +08 deg 0471 by (1) Ceres
The 13 November 1984 occultation of BD +08 deg 0471 was discovered during a photographic search carried out with the 0.5 meter Carnegie Double Astrograph at Lick Observatory and the Lowell Observatory PDS microdensitometer. Such a search was stimulated by the curious fact that few favorably located occultations of AGK3 or SAO catalog starts by Ceres will occur during the 1980s. The occultation on 13 November, however, is a particularly good event. The star is 1000 cubic M in V, yielding a predicted drop at occultation of about 10%. Such a drop can be detected by small telescopes equipped with photoelectric photometers, but is too small to be seen visually. The track was predicted to cross the Caribbean, Florida, southern Texas, and Mexico. Based on this prediction, preparations were made to observe the event in Mexico using four portable occultation data systems
The Value of Literacy Practices
The concepts of literacy events and practices have received considerable attention in educational research and policy. In comparison, the question of value, that is, ‘which literacy practices do people most value?’ has been neglected. With the current trend of cross-cultural adult literacy assessment, it is increasingly important to recognise locally valued literacy practices. In this paper we argue that measuring preferences and weighting of literacy practices provides an empirical and democratic basis for decisions in literacy assessment and curriculum development and could inform rapid educational adaptation to changes in the literacy environment. The paper examines the methodological basis for investigating literacy values and its potential to inform cross-cultural literacy assessments. The argument is illustrated with primary data from Mozambique. The correlation between individual values and respondents’ socio-economic and demographic characteristics is explored
Occurrence and population densities of yeast species in a fresh-water lake
Quantitative studies of yeasts present in surface and deep water samples from a fresh water body (Douglas Lake, Michigan) revealed 12 species ( Candida parapsilosis, C. pulcherrima, Cryptococcus albidus, Cr. diffluens, Cr. gastricus, Cr. laurentii, Rhodotorula glutinis, R. pilimanae, R. rubra, Trichosporon cutaneum, Debaryomyces sp., “black yeasts”). In two regions of surface sampling the population densities averaged 39.6 and 5.5 cells per 100 ml respectively, whereas the average deep water count was 40.3 cells per 100 ml. Yeasts of the genus Rhodotorula predominated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41778/1/10482_2005_Article_BF02046074.pd
Attention Performance in an Epidemiological Sample of Urban Children: The Role of Gender and Verbal Intelligence
We administered a comprehensive attentional battery to an epidemiologically defined sample of 435 first and second-grade children to assess the influence of gender and verbal intelligence on attention. The battery included three versions of the continuous performance test (CPT), two digit cancellation tasks, three subtests from the WISC-R, and the Wisconsin Card Sorting Test. The results indicated that both gender and intelligence had an impact on attentional performance. Girls performed better than boys; they made fewer errors on the CPT and obtained higher scores on the digit cancellation task and the Coding subtest of the WISC-R. Children with higher verbal intelligence also performed better on the attentional tests, but this advantage was not observed across measures or levels of performance. For example, children with limited verbal skills performed significantly worse than their peers only in measures with high processing demands(the degraded CPT and the distraction version of the digit cancellation task)
Herders and hazards: covariate dzud risk and the cost of risk management strategies in a Mongolian subdistrict
Studies of mobile pastoralist livelihoods have shown that a variety of sociotechnical practices have been developed to achieve reliable outputs from livestock in variable arid and semi-arid environments. This paper builds upon the concept of pastoralists as high-reliability seekers rather than risk-averse and makes a case for understanding Mongolian herders as well adapted to livestock production in highly variable climatic conditions within a certain threshold of risk and uncertainty. This system fails, however, during instances of high uncertainty and covariate risk such as in cases of the natural hazard dzud, which requires individual households to make significant cash investments in risk management. It forwards the idea that investing in local government—soum and bag level— administrative capacity and infrastructure is needed to build system resilience to covariate risk. Based on ethnographic research in rural Bayankhongor, this paper interrogates how dzud interfaces with socio-economic factors amongst pastoralists in central west Mongolia
Intramyocellular lipid saturation as a new metabolic biomarker
Background: Endurance trained athletic healthy volunteers (Athl-HV) and type 2 diabetes patients (T2D) have higher levels of lipids in their skele- tal myocytes compared to healthy controls. Despite apparently similar metabolic storage, they are at opposite ends of insulin sensitivity and cardio-metabolic risk. Purpose: We investigated if the degree of saturation of the IntraMyoCel- lular Lipids (IMCL) will differentiate Athl-HV from T2D; and explored if an exercise intervention will induce changes in the IMCL saturation. Methods: Male, age matched Athl-HV and T2D were enrolled (n=25/group). Athl-HV had ≥ 5 years endurance training, T2D were seden- tary. Subjects were studied at baseline and after an exercise intervention (4 week deconditioning in Athl-HV and supervised bike training at ≥ 65% of peakVO2, 5 hours/week x 8 weeks in T2D). All subjects underwent cardio-pulmonary exercise testing (CPET), blood sampling for insulin sen- sitivity (QUICKI*) and single voxel 1H-magnetic resonance spectroscopy (1H-MRS) of the right vastus lateralis. 1H-MRS was acquired on 3T Philips Achieva with a 16-channel coil, point-resolved spectroscopy, variable pulse power and optimized relaxation delay water suppression and analysed in LCModel. We derived fractional lipid mass (fLM) and fractions of saturated (fSL) and unsaturated (fUL) lipids. Data were analysed by t tests, shown as mean±SEM, statistical significance p < 0.05. Results: CPET and insulin sensitivity are presented in Table 1. T2D had higher fLM in the skeletal muscle compared to Athl-HV, at base- line (p=0.003) and after the exercise intervention (p=0.009), Figure 1A. At baseline, T2D had a different phenotype with a lower fSL and higher fUL compared to Athl-HV (82±3 vs 88±1% and 18±3 vs 12±1%, p=0.02 for both). Whilst deconditioning did not attract any significant changes in either fSL or fUL in Athl-HV (88±1 to 86±1% and 12±1 to 14±1, p=0.2), in contrast, with exercise training T2D significantly increased fSL (82±3 to 88±1%) and decreased their fUL (18±3 to 12±1%) (both p=0.01). Figure 1B and 1C. Conclusion: We demonstrate for the first time, in vivo, significant differ- ences in the IMCL amount and saturation between Athl-HV and T2D. IMCL saturation was changed by exercise training in T2D to mirror the phenotype seen in Athl-HV uncovering a new, independent biomarker of improved cardio-metabolic health
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The FANCM:p.Arg658* truncating variant is associated with risk of triple-negative breast cancer.
Breast cancer is a common disease partially caused by genetic risk factors. Germline pathogenic variants in DNA repair genes BRCA1, BRCA2, PALB2, ATM, and CHEK2 are associated with breast cancer risk. FANCM, which encodes for a DNA translocase, has been proposed as a breast cancer predisposition gene, with greater effects for the ER-negative and triple-negative breast cancer (TNBC) subtypes. We tested the three recurrent protein-truncating variants FANCM:p.Arg658*, p.Gln1701*, and p.Arg1931* for association with breast cancer risk in 67,112 cases, 53,766 controls, and 26,662 carriers of pathogenic variants of BRCA1 or BRCA2. These three variants were also studied functionally by measuring survival and chromosome fragility in FANCM -/- patient-derived immortalized fibroblasts treated with diepoxybutane or olaparib. We observed that FANCM:p.Arg658* was associated with increased risk of ER-negative disease and TNBC (OR = 2.44, P = 0.034 and OR = 3.79; P = 0.009, respectively). In a country-restricted analysis, we confirmed the associations detected for FANCM:p.Arg658* and found that also FANCM:p.Arg1931* was associated with ER-negative breast cancer risk (OR = 1.96; P = 0.006). The functional results indicated that all three variants were deleterious affecting cell survival and chromosome stability with FANCM:p.Arg658* causing more severe phenotypes. In conclusion, we confirmed that the two rare FANCM deleterious variants p.Arg658* and p.Arg1931* are risk factors for ER-negative and TNBC subtypes. Overall our data suggest that the effect of truncating variants on breast cancer risk may depend on their position in the gene. Cell sensitivity to olaparib exposure, identifies a possible therapeutic option to treat FANCM-associated tumors
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