229 research outputs found
Molecular outflows in the young open cluster IC348
We present a wide-field survey of the young open cluster IC348 for molecular
H2 outflows. Outflow activity is only found at its south-western limit, where a
new subcluster of embedded sources is in an early phase of its formation. If
the IC348 cluster had been built up by such subclusters forming at different
times, this could explain the large age-spread that Herbig (1998) found for the
IC348 member stars. In addition to several compact groups of H2 knots, our
survey reveals a large north-south oriented outflow, and we identify the newly
discovered far-infrared and mm-object IC348MMS as its source. New deep images
in the 1-0 S(1) line of molecular hydrogen trace the HH211 jet and counterjet
as highly-collimated chains of knots, resembling the interferometric CO and SiO
jets. This jet system appears rotated counter-clockwise by about 3 degrees with
respect to the prominent H2 bow shocks. Furthermore, we resolve HH211-mm as a
double point-like source in the mm-continuum.Comment: 10 pages, 9 figures, accepted for publication in Ap
Microclimat sous bâche à plat et son impact sur une culture de pomme de terre
Deux traitements ont été effectués dans un dispositif en blocs aléatoires complets avec quatre répétitions. Le premier sans bâche sert de témoin et le second utilise la bâche à plat comme couverture de la culture. La bâche en film polyéthylène perforé a été installée quinze jours après la plantation d’une culture de pomme de terre (Solanum tuberosum cv. Nicola) ayant reçu un traitement préventif contre le mildiou. La bâche a été retirée juste avant la récolte de la pomme de terre. Sous bâche à plat, les températures et les hygrométries de l’air ainsi que les températures du sol ont été supérieures à celles de l’extérieur. Les gouttelettes de condensation formées sous bâche ont réduit considérablement la transmission lumineuse. Les résultats agronomiques sont, par conséquent, affectés par ces conditions climatiques. Une nette amélioration de la croissance végétative de la pomme de terre a été observée sous bâche, mais l’attaque du mildiou a été plus importante sous bâche à plat que dans les parcelles témoins non couvertes qui ont été bien traitées. Ceci a affecté le rendement de pomme de terre sous bâche qui a enregistré une perte de 23% par rapport au témoin non couvert
A Study of the Luminosity and Mass Functions of the Young IC 348 Cluster using FLAMINGOS Wide-Field Near-Infrared Images
We present wide-field near-infrared (JHK) images of the young, 2 Myr IC 348
cluster taken with FLAMINGOS. We use these new data to construct an infrared
census of sources, which is sensitive enough to detect a 10 Mjup brown dwarf
seen through an extinction of Av=7mag. We examine the cluster's structure and
relationship to the molecular cloud and construct the cluster's K band
luminosity function. Using our model luminosity function algorithm, we derive
the cluster's initial mass function throughout the stellar and substellar
regimes and find that the IC 348 IMF is very similar to that found for the
Trapezium Cluster with both cluster IMFs having a mode between 0.2 - 0.08 Msun.
In particular we find that, similar to our results for the Trapezium, brown
dwarfs constitute only 1 in 4 of the sources in the IC 348 cluster. We show
that a modest secondary peak forms in the substellar IC 348 KLF, corresponding
to the same mass range responsible for a similar KLF peak found in the
Trapezium. We interpret this KLF peak as either evidence for a corresponding
secondary IMF peak at the deuterium burning limit, or as arising from a feature
in the substellar mass-luminosity relation that is not predicted by current
theoretical models. Lastly, we find that IC 348 displays radial variations of
its sub-solar (0.5 - 0.08 Msun) IMF on a parsec scale. Whatever mechanism that
is breaking the universality of the IMF on small spatial scales in IC 348 does
not appear to be acting upon the brown dwarf population, whose relative size
does not vary with distance from the cluster center.Comment: 53 pages, 20 figures, AASTeX5.0. Color version of Figure 1 made
available in jpg format. Figure(s) 2,3,5 are reduced in resolution. Accepted
14 Jan 2003 to the Astronomical Journa
International multicentre observational study to assess the efficacy and safety of a 0·5 mg kg−1 per day starting dose of oral corticosteroids to treat bullous pemphigoid
BackgroundEuropean guidelines propose a 0 center dot 5 mg kg(-1) per day dose of oral prednisone as initial treatment for bullous pemphigoid (BP). We assessed the safety and efficacy of this regimen depending on BP extent and general condition of the patients.MethodsIn a prospective international study, we consecutively included all patients diagnosed with BP. Patients received a 0 center dot 5 mg kg(-1) per day dose of prednisone, which was then gradually tapered 15 days after disease control, with the aim of stopping prednisone or maintaining minimal treatment (0 center dot 1 mg kg(-1) per day) within 6 months after the start of treatment. The two coprimary endpoints were control of disease activity at day 21 and 1-year overall survival. Disease severity was assessed according to the Bullous Pemphigoid Disease Area Index (BPDAI) score.ResultsIn total, 198 patients were included between 2015 and 2017. The final analysis comprised 190 patients with a mean age of 80 center dot 9 (SD 9 center dot 1) years. Control of disease activity was achieved at day 21 in 119 patients [62 center dot 6%, 95% confidence interval (CI) 55 center dot 3-69.5]; 18 of 24 patients (75%, 95% CI 53 center dot 3-90 center dot 2), 75 of 110 patients (68 center dot 8%, 95% CI 59 center dot 2-77 center dot 3) and 26 of 56 patients (46.4%, 95% CI 33 center dot 0-60 center dot 3) had mild, moderate and severe BP, respectively (P = 0 center dot 0218). A total of 30 patients died during the study. The overall Kaplan-Meier 1-year survival was 82 center dot 6% (95% CI 76 center dot 3-87 center dot 4) corresponding to 90 center dot 9%, 83 center dot 0% and 80 center dot 0% rates in patients with mild, moderate and severe BP, respectively (P = 0 center dot 5). Thresholds of 49 points for BPDAI score and 70 points for Karnofsky score yielded maximal Youden index values with respect to disease control at day 21 and 1-year survival, respectively.ConclusionsA 0 center dot 5 mg kg(-1) per day dose of prednisone is a valuable therapeutic option in patients with mild or moderate BP whose general condition allows them to be autonomous.</p
Could Fidicina mannifera (Hemiptera: Cicadoidea: Fidicinini) promote a resource pulse in two Brazilian Cerrado vegetation classes?
Characterisation of proteins in excretory/secretory products collected from salmon lice, Lepeophtheirus salmonis
Background The salmon louse, Lepeophtheirus salmonis, is an ectoparasitic copepod which feeds on the mucus, skin and blood of salmonid fish species. The parasite can persist on the surface of the fish without any effective control being exerted by the host immune system. Other ectoparasitic invertebrates produce compounds in their saliva, excretions and/or secretions which modulate the host immune responses allowing them to remain on or in the host during development. Similarly, compounds are produced in secretions of L. salmonis which are thought to be responsible for immunomodulation of the host responses as well as other aspects of crucial host-parasite interactions. Methods In this study we have identified and characterised the proteins in the excretory/secretory (E/S) products of L. salmonis using LC-ESI-MS/MS. Results In total 187 individual proteins were identified in the E/S collected from adult lice and pre-adult sea lice. Fifty-three proteins, including 13 serine-type endopeptidases, 1 peroxidase and 5 vitellogenin-like proteins were common to both adult and pre-adult E/S products. One hundred and seven proteins were identified in the adult E/S but not in the pre-adult E/S and these included serine and cysteine-type endopeptidases, vitellogenins, sphingomyelinase and calreticulin. A total of 27 proteins were identified in pre-adult E/S products but not in adult E/S. Conclusions The assigned functions of these E/S products and the potential roles they play in host-parasite interaction is discussed
Structures of (5′S)-8,5′-Cyclo-2′-deoxyguanosine Mismatched with dA or dT
pubs.acs.org/cr
The impact of ENSO on Southern African rainfall in CMIP5 ocean atmosphere coupled climate models
We study the ability of 24 ocean atmosphere global coupled models from the Coupled Model Intercomparison Project 5 (CMIP5) to reproduce the teleconnections between El Niño Southern Oscillation (ENSO) and Southern African rainfall in austral summer using historical forced simulations, with a focus on the atmospheric dynamic associated with El Niño. Overestimations of summer rainfall occur over Southern Africa in all CMIP5 models. Abnormal westward extensions of ENSO patterns are a common feature of all CMIP5 models, while the warming of the Indian Ocean that happens during El Niño is not correctly reproduced. This could impact the teleconnection between ENSO and Southern African rainfall which is represented with mixed success in CMIP5 models. Large-scale anomalies of suppressed deep-convection over the tropical maritime continent and enhanced convection from the central to eastern Pacific are correctly simulated. However, regional biases occur above Africa and the Indian Ocean, particularly in the position of the deep convection anomalies associated with El Niño, which can lead to the wrong sign in rainfall anomalies in the northwest part of South Africa. From the near-surface to mid-troposphere, CMIP5 models underestimate the observed anomalous pattern of pressure occurring over Southern Africa that leads to dry conditions during El Niño years
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