The Rumsfeld Effect: The unknown unknown

A set of studies tested whether people can use awareness of ignorance to provide enhanced test consistency over time if they are allowed to place uncertain items into a “don’t know” category. For factual knowledge this did occur, but for a range of other forms of knowledge relating to conceptual knowledge and personal identity, no such effect was seen. Known unknowns would appear to be largely restricted to factual kinds of knowledge

A line confusion-limited millimeter survey of Orion KL. III. Sulfur oxide species

We present a study of the sulfur-bearing species detected in a line confusion-limited survey towards Orion KL performed with the IRAM 30m telescope in the range 80-281 GHz. The study is part of an analysis of the line survey divided into families of molecules. Our aim is to derive accurate physical conditions and molecular abundances in the different components of Orion KL from observed SO and SO2 lines. First we assumed LTE conditions obtain rotational temperatures. We then used a radiative transfer model, assuming either LVG or LTE excitation to derive column densities of these molecules in the different components of Orion KL. We have detected 68 lines of SO, 34SO, 33SO, and S18O and 653 lines of SO2, 34SO2, 33SO2, SO18O and SO2 v2=1. We provide column densities for all of them and also upper limits for the column densities of S17O, 36SO, 34S18O, SO17O and 34SO2 v2=1 and for several undetected sulfur-bearing species. In addition, we present 2'x2' maps around Orion IRc2 of SO2 transitions with energies from 19 to 131 K and also maps with four transitions of SO, 34SO and 34SO2. We observe an elongation of the gas along the NE-SW direction. An unexpected emission peak appears at 20.5 km/s in most lines of SO and SO2. A study of the spatial distribution of this emission feature shows that it is a new component ~5" in diameter, which lies ~4" west of IRc2. We suggest the emission from this feature is related to shocks associated to the BN object. The highest column densities for SO and SO2 are found in the high-velocity plateau (a region dominated by shocks) and in the hot core. These values are up to three orders of magnitude higher than the results for the ridge components. We also find high column densities for their isotopologues in both components. Therefore, we conclude that SO and SO2 are good tracers, not only of regions affected by shocks, but also of regions with warm dense gas.Comment: Paper (ref AA/2013/21285) accepted for publication by A&A. 52 Pages, 26 figures, 13 table

Extended warm gas in Orion KL as probed by methyl cyanide

In order to study the temperature distribution of the extended gas within the Orion Kleinmann-Low nebula, we have mapped the emission by methyl cyanide (CH3CN) in its J=6_K-5_K, J=12_K-11_K, J=13_K-12_K, and J=14_K-13_K transitions at an average angular resolution of ~10 arcsec (22 arcsec for the 6_K-5_K lines), as part of a new 2D line survey of this region using the IRAM 30m telescope. These fully sampled maps show extended emission from warm gas to the northeast of IRc2 and the distinct kinematic signatures of the hot core and compact ridge source components. We have constructed population diagrams for the four sets of K-ladder emission lines at each position in the maps and have derived rotational excitation temperatures and total beam-averaged column densities from the fitted slopes. In addition, we have fitted LVG model spectra to the observations to determine best-fit physical parameters at each map position, yielding the distribution of kinetic temperatures across the region. The resulting temperature maps reveal a region of hot (T > 350 K) material surrounding the northeastern edge of the hot core, whereas the column density distribution is more uniform and peaks near the position of IRc2. We attribute this region of hot gas to shock heating caused by the impact of outflowing material from active star formation in the region, as indicated by the presence of broad CH3CN lines. This scenario is consistent with predictions from C-shock chemical models that suggest that gas-phase methyl cyanide survives in the post-shock gas and can be somewhat enhanced due to sputtering of grain mantles in the passing shock front.Comment: 24 pages, 20 figures, accepted for publication in A&

A combined IRAM and Herschel/HIFI study of cyano(di)acetylene in Orion KL: tentative detection of DC3N

We present a study of cyanoacetylene (HC3N) and cyanodiacetylene (HC5N) in Orion KL, through observations from two line surveys performed with the IRAM 30m telescope and the HIFI instrument on board the Herschel telescope. The frequency ranges covered are 80-280 GHz and 480-1906 GHz. We model the observed lines of HC3N, HC5N, their isotopologues (including DC3N), and vibrational modes, using a non-LTE radiative transfer code. To investigate the chemical origin of HC3N and DC3N in Orion KL, we use a time-dependent chemical model. We detect 40 lines of the ground state of HC3N and 68 lines of its 13C isotopologues. We also detect 297 lines of six vibrational modes of this molecule (nu_7, 2nu_7, 3nu_7, nu_6, nu_5, and nu_6+nu_7) and 35 rotational lines of the ground state of HC5N. We report the first tentative detection of DC3N in a giant molecular cloud with a DC3N/HC3N abundance ratio of 0.015. We provide column densities and isotopic and molecular abundances. We also perform a 2x2" map around Orion IRc2 and we present maps of HC3N lines and maps of lines of the HC3N vibrational modes nu_6 and nu_7. In addition, a comparison of our results for HC3N with those in other clouds allows us to derive correlations between the column density, the FWHM, the mass, and the luminosity of the clouds. The high column densities of HC3N obtained in the hot core, make this molecule an excellent tracer of hot and dense gas. In addition, the large frequency range covered reveals the need to consider a temperature and density gradient in the hot core in order to obtain better line fits. The high D/H ratio (comparable to that obtained in cold clouds) that we derive suggests a deuterium enrichment. Our chemical models indicate that the possible deuterated HC3N present in Orion KL is formed during the gas-phase. This fact provides new hints concerning the processes leading to deuteration.Comment: 50 pages, 33 figures, 13 tables. Accepted for publication in A&

The hot core towards the intermediate mass protostar NGC7129 FIRS 2: Chemical similarities with Orion KL

NGC 7129 FIRS 2 (hereafter FIRS 2) is an intermediate-mass (2 to 8 Msun) protostar located at a distance of 1250 pc. High spatial resolution observations are required to resolve the hot core at its center. We present a molecular survey from 218200 MHz to 221800 MHz carried out with the IRAM Plateau de Bure Interferometer. These observations were complemented with a long integration single-dish spectrum taken with the IRAM 30m telescope. We used a Local Thermodynamic Equilibrium (LTE) single temperature code to model the whole dataset. The interferometric spectrum is crowded with a total of ~300 lines from which a few dozens remain unidentified yet. The spectrum has been modeled with a total of 20 species and their isomers, isotopologues and deuterated compounds. Complex molecules like methyl formate (CH3OCHO), ethanol (CH3CH2OH), glycolaldehyde (CH2OHCHO), acetone (CH3COCH3), dimethyl ether (CH3OCH3), ethyl cyanide (CH3CH2CN) and the aGg' conformer of ethylene glycol (aGg'-(CH2OH)_2) are among the detected species. The detection of vibrationally excited lines of CH3CN, CH3OCHO, CH3OH, OCS, HC3N and CH3CHO proves the existence of gas and dust at high temperatures. In fact, the gas kinetic temperature estimated from the vibrational lines of CH3CN, ~405 K, is similar to that measured in massive hot cores. Our data allow an extensive comparison of the chemistry in FIRS~2 and the Orion hot core. We find a quite similar chemistry in FIRS 2 and Orion. Most of the studied fractional molecular abundances agree within a factor of 5. Larger differences are only found for the deuterated compounds D2CO and CH2DOH and a few molecules (CH3CH2CN, SO2, HNCO and CH3CHO). Since the physical conditions are similar in both hot cores, only different initial conditions (warmer pre-collapse phase in the case of Orion) and/or different crossing time of the gas in the hot core can explain this behavior.Comment: 30 pages, 9 figure

RECYCLING BROILER LITTER AND CAPRINE RUMEN CONTENT AS LOW COST BY PRODUCT FEEDING STUFFS FOR GOAT PRODUCTION

Experiments were conducted to evaluate the potentials of broiler litter (BL) and caprine rumen content (CRC) as low cost by product feeding stuffs for goats. Twenty (20) West African Dwarf goats (WAD) with average weight of 10kg were randomly assigned to five dietary treatments of 0%CRC/30%BL, 10%CRC/20%BL, 20%CRC/10%BL, 30%CRC/0BL% and 0BL%/0%CRC (control) for diets A to E, respectively. Results indicated that dry matter (DM) intake of goats decreased (p>0.05) with increasing level of CRC in the diets. Goats on diet A had the best performance in terms of daily gain (g/day) and feed: gain ratio with goats on diet D having the least (p<0.05) performance.  The DM and CP digestibilities followed the same trend across the dietary treatments with goats fed diet D having significantly (p<0.05) lower digestibility compared to the other treatments.  Blood parameters monitored fell within the range required for goats and varied (p<0.05) across the treatments with exception of total protein and blood glucose. The carcass characteristics of WAD goats as a result of feeding BL with CRC were not influenced (p>0.05) by the dietary treatments, while the meat composition varied (p<0.05) in the CP and fat contents. It is concluded that supplementing BL in CRC diets at 20 and 30%BL, respectively, has the potential of improving feed intake, weight gain, digestibility and carcass quality in WAD goats for profitable performance.Â

Transport urbain au Benin et pollution atmosphérique: évaluation quantitative de certains polluants chimiques de Cotonou

L’atmosphère dans la ville de Cotonou au Bénin en Afrique de l’Ouest, se caractérise par la présence de poussières soulevées au cours de la circulation sur toutes les voies et presque partout dans cette ville, par d’épaisses fumées opaques, en particulier au niveau des grandes artères et des carrefours. Ce phénomène est lié à une utilisation des moto à deux roues notamment les taxis–moto appelés « Zémidjan » dont le nombre en 2005 est estimé à 96.095 selon les statistiques de la mairie de Cotonou. Le présent article vise l’évaluation quantitative de certains polluants chimiques supposés nocifs et ayant fait l’objet de réglementation au niveau du Bénin. Il met en relief le rôle joué par le transport dans l’émission de ces polluants gazeux. A cet effet, les taux dans l’air du monoxyde de carbone (CO), du dioxyde d’azote (NO2), du dioxyde de soufre (SO2) et du plomb ont été déterminés. Le monoxyde de carbone et le dioxyde d’azote donnent des taux dépassant souvent le seuil retenu par la réglementation Béninoise. Le carrefour du grand marché Tokpa de Cotonou présente les plus forts taux mesurés avec un maximum de 214,7 mg/m3 de CO. La quantité du plomb fixée varie avec le temps d’exposition. Le travail a confirmé le rôle principal de pollution de l’air joué par le transport urbain à Cotonou. © 2013 International Formulae Group. All rights reserved.Mots clés: Transport urbain, Pollution atmosphérique, Evaluation quantitative, polluants chimiques, Cotonou

EVALUATION OF THE AGRONOMIC PERFORMANCE AND NUTRITIVE VALUES OF TEPHROSIA BRACTEOLATA GUILL. & PERR. AND GMELINA ARBOREA ROXB PRUNNINGS AT DIFFERENT STAGES OF GROWTH

This study was carried out to investigate the growth, dry matter yield and chemical composition of Tephrosia bracteolata and Gmelina arborea at Teaching and Research Farm, Federal University of Agriculture, Abeokuta, Nigeria. The objective of this study was to evaluate the effect of different stages of growth of T. bracteolata and G. arborea on their agronomic performance, herbage yield and nutritive value in the humid zone of Nigeria. Data were collected at 8, 12, 16 and 20 weeks after planting (WAP). Results showed that T. bracteolata attained the height of 161 cm at 20 WAP, though not significantly different from the height at 16 WAP. The leaf number (24), branch number (7) and dry matter yield of T. bracteolata were recorded highest at 16 WAP. The height of G. arborea was on constant increase throughout the experimental period. The crude protein (CP) and ether extract (EE) contents of the two browse plants were highest at 8 WAP and thereafter, declined throughout the experimental period. Fibre fractions, the neutral detergent fibre (NDF), acid detergent fibre (ADF) and acid detergent lignin (ADL) had a least value for both browse species at 8 WAP and highest values at 20 WAP. From the study, considering the dry matter yield and nutritive value, T. bracteolata being an annual species, can be harvested at 16 WAP when the quality and quantity will support livestock productivity and can be conserved to be fed to ruminant animals during dry season when feed availability and quality are extremely low. However, planting of G. arborea should be encouraged being a perennial browse plant that will support livestock productivity during the dry season in the tropics. In conclusion, T. bracteolata and G. arborea grow rapidly and are recommended as forage of high nutritive values that meet ruminant animal protein requirements especially during the dry season

Elasmobranch spatial segregation in the western Mediterranean

Basic information on the distribution and habitat preferences of ecologically important species is essential for their management and protection. This study focuses on the depth related trends and the geographic patterns that shape the community of the elasmobranch species in the Balearic Islands (Mediterranean Sea) using data collected from 2001 to 2009. Non-metric Multi-Dimensional Scaling (MDS) ordination was used to detect zonation patterns in the community. Generalized Additive Models (GAMs) were applied to analyse spatial and temporal variation in elasmobranch community descriptors (abundance, biomass, mean fish weight, number of species and diversity), as well as the abundance and mean length of the four individual species (S. canicula, G. melastomus, R. clavata, R. miraletus). Depth was the main factor determining the assemblage composition, and the MDS analysis identified four main groups with 60% of the similarity found to correspond to the continental shelf, shelf break, upper slope and middle slope of the surveyed area. GAM analysis identified spatial patterns that were independent of the bathymetric distribution preference. Although depth was a strong predictor for all the analyses performed, the geographic variation in the elasmobranch abundance was also important. The results also show a reduction in the mean length of the elasmobranch species in the areas with high fishing intensity. Our study evidences a clear spatial segregation of the main species throughout the ontogeny because the geographic and bathymetric effects were highly size dependent, with clear differences between the bathymetric distributions of juveniles and adults but no clear spatial overlapping. This study sheds new light on the spatial distribution of the elasmobranch species off the Balearic Islands, which is essential information for protecting marine organisms along with their habitats and promoting ecosystem based managementPublicado