The Extraordinary Infrared Spectrum of NGC 1222 (Mkn 603)

The infrared spectra of starburst galaxies are dominated by the low-excitation lines of [NeII] and [SIII], and the stellar populations deduced from these spectra appear to lack stars larger than about 35 Msun. The only exceptions to this result until now were low metallicity dwarf galaxies. We report our analysis of the mid-infrared spectra obtained with IRS on Spitzer of the starburst galaxy NGC 1222 (Mkn 603). NGC 1222 is a large spheroidal galaxy with a starburst nucleus that is a compact radio and infrared source, and its infrared emission is dominated by the [NeIII] line. This is the first starburst of solar or near-solar metallicity, known to us, which is dominated by the high-excitation lines and which is a likely host of high mass stars. We model the emission with several different assumptions as to the spatial distibution of the high- and low-excitation lines and find that the upper mass cutoff in this galaxy is 40-100 Msun.Comment: accepted, Astronomical Journal. 29 pp, 4 figures. In replacement version an acknowledgment to NRAO is adde

Picard group of hypersurfaces in toric 3-folds

We show that the usual sufficient criterion for a generic hypersurface in a smooth projective manifold to have the same Picard number as the ambient variety can be generalized to hypersurfaces in complete simplicial toric varieties. This sufficient condition is always satisfied by generic K3 surfaces embedded in Fano toric 3-folds.Comment: 14 pages. v2: some typos corrected. v3: Slightly changed title. Final version to appear in Int. J. Math., incorporates many (mainly expository) changes suggested by the refere

Computation of Dancoff Factors for Fuel Elements Incorporating Randomly Packed TRISO Particles

A new method for estimating the Dancoff factors in pebble beds has been developed and implemented within two computer codes. The first of these codes, INTRAPEB, is used to compute Dancoff factors for individual pebbles taking into account the random packing of TRISO particles within the fuel zone of the pebble and explicitly accounting for the finite geometry of the fuel kernels. The second code, PEBDAN, is used to compute the pebble-to-pebble contribution to the overall Dancoff factor. The latter code also accounts for the finite size of the reactor vessel and for the proximity of reflectors, as well as for fluctuations in the pebble packing density that naturally arises in pebble beds

APPLICATION OF THE STOCHASTIC TRANSPORT THEORY TO REACTIVITY MEASUREMENTS IN A SUBCRITICAL ASSEMBLY DRIVEN BY A PULSED SOURCE

ABSTRACT Using the stochastic transport theory formalism developed by Muñoz-Cobo for a radioactive source and for a spallation source, we derive an expression for the Cross Power Spectral Density (CPSD) for a subcritical system driven by an external pulsed neutron source. The derivation of this expression has been done in a rigorous and general way including the energy and spatial dependency. The CPSD shows some peaks at the source frequency together with its harmonics. The final expression containing some approximations (fundamental mode analysis; Dirac delta pulses for the source) is compared with calculations using a Monte Carlo code. In the future, comparisons with measurements in the MUSE project are planned

Double adjoint method for determining the contribution of composition to reactivity at different times

a b s t r a c t The double adjoint method uses the adjoint reactivity and transmutation problems to describe how the system composition is related to the system reactivity at different points in time. Values of the contribution to the reactivity are determined using the adjoint reactivity problem, and these are then used as the source function for the adjoint transmutation problem. The method is applied to the problem of determining the contribution of the beginning of cycle composition to the end of cycle reactivity. It is tested in both fast and thermal systems by comparing the behaviour of the multiplication factor at the end of cycle in calculations with perturbed initial compositions to that predicted by the double adjoint method. The results from the fast system are good, while those from the thermal system are less favourable. This is believed to be due to the method neglecting the coupling between the composition and the flux, which plays a more significant role in thermal systems than fast ones. The importance of correcting for the effects of the fuel compound is also established. The values found are used in calculations to determine the appropriate fuel reloading of the systems tested, with the aim of duplicating the behaviour of the multiplication factor of the original system. Again the fast system gives good results, while the thermal system is less accurate. The double adjoint method is also used for a definition of breeding ratio, and some of the features of this definition are illustrated by examining the effects of different feed materials and reprocessing schemes. The method is shown to be a useful tool for the comparison of the reactivity behaviour of different fuel compositions, particularly its inclusion of the effects of the feed and fuel compound materials. The breeding ratio definition can be applied to non-equilibrium cycles, a significant advantage over many existing definitions

Rangelands Vegetation Mapping at Species Composition Level Using the \u3cb\u3eSPiCla\u3c/b\u3e Method: \u3cb\u3eS\u3c/b\u3eDM Based \u3cb\u3ePi\u3c/b\u3exel \u3cb\u3eCla\u3c/b\u3essification and Fuzzy Accuracy. A New Approach of Map Making

Vegetation maps have been made since centuries. The vegetation cover was represented as homogeneous mapping units (polygons), representing different vegetation types, where each type consists a combination of different plant species (floristic composition). More recent, with the use of satellite imagery, the polygons have been replaced by pixels with similar content as the polygon maps. In both approaches, field-observations were linked to the mapping units (polygons or pixels) often resulting in a complex of different vegetation types per mapping unit. In our new approach field data (sample points) on presence and abundance of individual grass species are spatially extrapolated based on a set of environmental layers, using the species distribution modelling approach (SDM). When combined, each pixel will contain its own set of information about the vegetation structure and its floristic composition. This new methodology (SPiCla) results in a very accurate and detailed vegetation map at pixel level, allowing extraction of very detailed, accurate and easy to update spatial information on e.g., forage production and quality (palatability) for rangelands management. As no exact boundaries exist, but only gradients, we introduced fuzzy accuracy. The resolution mainly depends on the resolution of (or one of) the environmental layers used, scale of interest and workability. The methodology is generic and applicable to any other region in the world

Dispatched Homolog 2 is targeted by miR-214 through a combination of three weak microRNA recognition sites

MicroRNAs (miRNAs) regulate gene expression by inhibiting translation of target mRNAs through pairing with miRNA recognition elements (MREs), usually in 3′ UTRs. Because pairing is imperfect, identification of bona fide mRNA targets presents a challenge. Most target recognition algorithms strongly emphasize pairing between nucleotides 2–8 of the miRNA (the ‘seed’ sequence) and the mRNA but adjacent sequences and the local context of the 3′ UTR also affect targeting. Here, we show that dispatched 2 is a target of miR-214. In zebrafish, dispatched 2 is expressed in the telencephalon and ventral hindbrain and is essential for normal zebrafish development. Regulation of dispatched 2 by miR-214 is via pairing with three, noncanonical, weak MREs. By comparing the repression capacity of GFP reporters containing different dispatched 2 sequences, we found that a combination of weak sites, which lack canonical seed pairing, can effectively target an mRNA for silencing. This finding underscores the challenge that prediction algorithms face and emphasizes the need to experimentally validate predicted MREs

Parents' expectations of the outpatient care for daytime urinary incontinence in children:A qualitative study

INTRODUCTION: Daytime urinary incontinence (UI) can have an enormous impact on a child's life, lowering both self-esteem and quality of life. Although most children start therapy after their first visit to our outpatient clinic, no studies have reported on parents' or patients' expectations of care for daytime UI in this setting. OBJECTIVE: We aimed to explore the expectations of the parents of children referred to an outpatient clinic for daytime UI. STUDY DESIGN: This was a qualitative study that involved performing semi-structured interviews with the parents of children who had been referred for daytime UI (with or without nocturnal enuresis). Interviews took place between July 2018 and October 2018 and continued until saturation was reached. The results were transcribed verbatim and analyzed according to Giorgi's strategy of phenomenological data analysis. RESULTS: Nine parents of children, aged 5-12 years old, were interviewed, revealing "(Experienced) Health," Self-management," and "Social Impact" as the main themes that influenced parental expectations. All parents wanted to know if there was a medical explanation for UI, some were satisfied when diagnostics revealed no underlying condition, and others wanted treatment. Parents expressed no preferences about diagnostics or the content and duration of treatment, but they hoped that any previously attempted ineffective steps would not be repeated. Some parents defined treatment success as their child becoming completely dry, but most stated that learning coping strategies was more important. DISCUSSION: This is the first study to explore the expectations of parents when attending outpatient care for children with daytime UI. We employed a strong theoretical framework with a clear interview guide. The main limitations are that we only interviewed parents and that this was a qualitative study, precluding the drawing of firm conclusions. Nevertheless, our results point to the need for quantitative evaluation. CONCLUSION: Expectations seem to be influenced by (experienced) health, efforts at self-management, and the social impact of UI, making it critical that these themes are addressed. It was interesting to note that parents do not always attend outpatient departments with the goal of completely resolving daytime UI. Instead, some only want to know if there is an underlying medical condition or want to reduce the social impact by learning coping mechanisms. Excluding underlying medical conditions may therefore stimulate acceptance of watchful waiting without the need to start treatment