414 research outputs found

    Herschel, Spitzer and Magellan infrared observations of the star-forming region RCW 121 (IRAS 17149−3916)

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    We present new deep near-infrared broad- and narrow-band imaging and low-resolution spec-troscopy of the star formation region RCW 121 (IRAS 17149−3916) which we analyse incombination withHerschel(70, 160, 250, 350 and 500ÎŒm) andSpitzer(3.6, 4.5, 5.8 and 8ÎŒm)images. The near-infrared photometry reveals the presence of a stellar cluster of approximatesize of 92 arcsec which is composed of at least 264 members, approximately 25 per cent ofthese showing excess emission atλ>2.0ÎŒm, indicative of circumstellar discs. Isochronescorresponding to ages 0.5–1.0 Myr andAV=7.8 fit well the position of a large fraction of likelycluster members in theKsversusH−Ksdiagram. We find three massive star-forming coreslocated in the boundaries of an expanding HIIregion ionized by a central O-type star. Fromtheir far-infrared spectral energy distributions (SEDs) we derive masses and temperatures ofthe dense cores. When these young stellar objects (YSOs) have warm emission components,the 1.2–500ÎŒm SEDs are fitted with Robitaille et al.’s star–disc-envelope model to obtain theirphysical parameters. The masses of the three YSOs are between 8 and 10 M . The youngestsite (core I) is undetected atλ<100ÎŒm and is at the earliest evolutionary stage that cancurrently be detected. The other two cores (II and III) contain YSOs of similar masses andhave near-infrared counterparts, which imply a more advanced evolutionary stage. The YSOat core II has been found to have associated a jet, with strong H2line emission, co-existingwith an H2O maser source. RCW 121 is another example of multiple star formation beingtriggered by the expansion of a single HIIregion.Fil: Tapia, M.. Universidad Nacional AutĂłnoma de MĂ©xico; MĂ©xicoFil: Persi, P.. Istituto Astrofisica e Planetologia Spaziale. Roma; ItaliaFil: Roth, Markus Albert. Las Campanas Observatory. La Serena; ChileFil: Elia, D.. Istituto Astrofisica e Planetologia Spaziale. Roma; ItaliaFil: Molinari, S.. Istituto Astrofisica e Planetologia Spaziale. Roma; ItaliaFil: Saldaño, Hugo Pablo. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Gomez, Mercedes Nieves. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; Argentin

    The interstellar extinction in the open clusters Tr 14, Tr 15, Tr 16/Cr 232 and Cr 228 in NGC 3372 : New near-infrared photometry

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    Near-infrared JHKL photometry of more than 200 stars, members of the open clusters Tr 14, Tr 15, Tr 16, Cr 228 and Cr 232 in the Carina Nebula are presented. From comparing these results with the available visual photometry and spectroscopy, it is found that, except in Tr 15, the intracluster reddening is characterized by a ‘normal’ extinction law at λ>0.5ÎŒm but is highly anomalous and variable in the U- and B-bands. This behaviour may be explained by the presence of intracluster interstellar grains ‘processed’ by shock waves presumably associated with the explosive history of ƞ Carinae. All clusters are found to be at the same distance from the Sun at d=2.4±0.2kpcorV0−Mv=11.9±0.2⁠. The total amount of reddening, though, differs significantly from cluster to cluster.Facultad de Ciencias AstronĂłmicas y GeofĂ­sica

    Typing linear algebra : a biproduct-oriented approach

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    Interested in formalizing the generation of fast running code for linear algebra applications, the authors show how an index-free, calculational approach to matrix algebra can be developed by regarding matrices as morphisms of a category with biproducts. This shifts the traditional view of matrices as indexed structures to a type-level perspective analogous to that of the pointfree algebra of programming. The derivation of fusion, cancellation and abide laws from the biproduct equations makes it easy to calculate algorithms implementing matrix multiplication, the central operation of matrix algebra, ranging from its divide-and-conquer version to its vectorization implementation. From errant attempts to learn how particular products and coproducts emerge from biproducts, not only blocked matrix algebra is rediscovered but also a way of extending other operations (e.g. Gaussian elimination) blockwise, in a calculational style, is found. The prospect of building biproduct-based type checkers for computer algebra systems such as MatlabTM is also considered.Fundação para a CiĂȘncia e a Tecnologia (FCT

    The metabolic adaptation evoked by arginine enhances the effect of radiation in brain metastases

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    Selected patients with brain metastases (BM) are candidates for radiotherapy. A lactatogenic metabolism, common in BM, has been associated with radioresistance. We demonstrated that BM express nitric oxide (NO) synthase 2 and that administration of its substrate l-arginine decreases tumor lactate in BM patients. In a placebo-controlled trial, we showed that administration of l-arginine before each fraction enhanced the effect of radiation, improving the control of BM. Studies in preclinical models demonstrated that l-arginine radiosensitization is a NO-mediated mechanism secondary to the metabolic adaptation induced in cancer cells. We showed that the decrease in tumor lactate was a consequence of reduced glycolysis that also impacted ATP and NAD+ levels. These effects were associated with NO-dependent inhibition of GAPDH and hyperactivation of PARP upon nitrosative DNA damage. These metabolic changes ultimately impaired the repair of DNA damage induced by radiation in cancer cells while greatly sparing tumor-infiltrating lymphocytes.Fil: Marullo, Rossella. Cornell University; Estados UnidosFil: Castro, Monica. Universidad de Buenos Aires; ArgentinaFil: Yomtoubian, Shira. Cornell University; Estados UnidosFil: Nieves Calvo Vidal, M.. Cornell University; Estados UnidosFil: Revuelta, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Krumsiek, Jan. Cornell University; Estados UnidosFil: Nicholas, Andrew P.. Cornell University; Estados UnidosFil: Cresta Morgado, Pablo. Universidad de Buenos Aires; ArgentinaFil: Yang, ShaoNing. Cornell University; Estados UnidosFil: Medina, Vanina Araceli. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; ArgentinaFil: Roth, Berta María Cristina. Universidad de Buenos Aires; ArgentinaFil: Bonomi, Marcelo. Ohio State University; Estados UnidosFil: Keshari, Kayvan R.. Memorial Sloan Kettering Cancer Center; Estados UnidosFil: Mittal, Vivek. Cornell University; Estados UnidosFil: Navigante, Alfredo Hugo. Universidad de Buenos Aires; ArgentinaFil: Cerchietti, Leandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; Argentin

    Radiofrequency multipole traps: Tools for spectroscopy and dynamics of cold molecular ions

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    Multipole radiofrequency ion traps are a highly versatile tool to study molecular ions and their interactions in a well-controllable environment. In particular the cryogenic 22-pole ion trap configuration is used to study ion-molecule reactions and complex molecular spectroscopy at temperatures between few Kelvin and room temperatures. This article presents a tutorial on radiofrequency ion trapping in multipole electrode configurations. Stable trapping conditions and buffer gas cooling, as well as important heating mechanisms, are discussed. In addition, selected experimental studies on cation and anion-molecule reactions and on spectroscopy of trapped ions are reviewed. Starting from these studies an outlook on the future of multipole ion trap research is given

    Panorama view of Innovation in Brazilian Small Businesses

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    The ALI Program of the Brazilian Micro and Small Business Support Service (SEBRAE) has monitored over 150,000 small businesses throughout Brazil over the last few years. Within this setting, this article aims to demonstrate the panorama of innovation and management of Brazilian micro and small businesses (MSBs) that were in the initial phase of the ALI program. The data collected, between the years of 2015 and 2016, allowed to assess the average of points in each of the thirteen dimensions of the Innovation Radar (IR) and the eight dimensions of the Excellence Management Model (EMM). The analysis of the 21 dimensions was performed in a sample of 27,422 small businesses from all over Brazil, which was extracted from the Management and Monitoring System of the ALI - SistemAli Program of Sebrae. Regarding IR results, four dimensions stand out as their means are higher than the others: Brand (3.1), Platform (2.9), Offer (2.7), and Client Relationship (2.7). Besides, the results of the Excellence Management Model (EMM) show that Brazilian MSBs still need to improve, since no dimension evaluated has reached the average value of the scale

    Psychological impact of anti-VEGF treatments for wet macular degeneration-a review.

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    To review the current literature on the psychological impact of anti-VEGF treatments for wet age-related macular degeneration (wAMD), in terms of patients' experiences of receiving these treatments, and the impact of these treatments for patients' mental health and quality of life.We critically analyzed current literature evaluating psychological impact of anti-VEGF treatments for wAMD. Primary searches of PubMed, Science Direct, and Web of Science were conducted in July and August of 2015. We reviewed all papers on the topic published until August 5, 2015.Our literature search found 14 papers addressing the psychological impact of anti-VEGF treatments for wAMD. Results highlighted potential anxieties and experiences of pain caused by receiving regular intravitreal injections. A positive visual outcome of anti-VEGF therapy is associated with positive vision-related QOL outcomes, although such association seems to be dependent on improvements on visual acuity. In the literature reviewed, patients receiving anti-VEGF treatments showed a prevalence rate of depression between 20 and 26 %.Although anti-VEGF treatments can cause some anxiety and being experienced as a stressful event, especially in the beginning of the treatment, preliminary findings suggest a potential benefit for long-term vision-related quality of life. Further longitudinal and qualitative research should bring more evidence on the positive and negative effects of these treatments on patients' long-term mental health

    The state of the Martian climate

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    60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

    The impact of individual Cognitive Stimulation Therapy (iCST) on cognition, quality of life, caregiver health, and family relationships in dementia: a randomized controlled trial

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    Background: Cognitive Stimulation Therapy (CST) is a well-established group psychosocial intervention for people with dementia. There is evidence that homebased programmes of cognitive stimulation delivered by family caregivers may benefit both the person and the caregiver. However, no previous studies have evaluated caregiver-delivered CST. This study aimed to evaluate the effectiveness of a home-based, caregiver-led individual Cognitive Stimulation Therapy (iCST) program in (i) improving cognition and quality of life (QoL) for the person with dementia and (ii) mental and physical health (wellbeing) for the caregiver. Methods and Findings: A single-blind, pragmatic randomized trial (RCT) at eight study sites across the UK. The intervention and blinded assessment of outcomes were conducted in participants’ homes. 356 people with mild to moderate dementia and their caregivers recruited from memory services, and community mental health teams. Participants were randomly assigned to iCST (75, 30 minute sessions) or treatment as usual (TAU) control over 25 weeks. iCST sessions consisted of themed activities designed to be mentally stimulating and enjoyable. Caregivers delivering iCST received training and support from an unblind researcher. Primary outcomes were cognition (Alzheimer’s Disease Assessment Scale cognitive [ADAS-Cog]) and self-reported quality of life (QoL) (Quality of Life Alzheimer’s Disease [QoL-AD]) for the person with dementia, and general health status (Short Form-12 [SF-12]) for the caregiver. Secondary outcomes included: quality of the caregiving relationship from the perspectives of the person and of the caregiver (Quality of the Carer Patient Relationships Scale), and health-related QoL (EQ5D) for the caregiver. Intention to treat (ITT) analyses were conducted. At the post-test (26 weeks), there were no differences between the iCST and TAU groups in the outcomes of cognition (MD = -0·55, 95% CI -2·00 to 0·90; p=0·45), and self-reported quality of life (QoL) (MD = -0·02, 95% CI -1·22 to 0·82; p= 0·97) for people with dementia, or caregivers’ general health status (MD=0·13, 95% CI -1·65 to 1·91; p=0·89). However, people with dementia receiving iCST rated the relationship with their caregiver more positively (MD = 1·77, 95% CI 0·26 to 3·28; p=0·02) and iCST improved QoL for caregivers (EQ-5D, MD = 0·06, 95% CI 0·02 to 0·10; p=0·01). Forty percent (72/180) of dyads allocated to iCST completed at least two sessions per week, with 22% (39/180) completing no sessions at all. Study limitations include low adherence to the intervention. Conclusions: There was no evidence that iCST has an effect on cognition or QoL for people with dementia. However, participating in iCST appeared to enhance the quality of the caregiving relationship and caregivers’ QoL
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