Remote lab experiments: Opening possibilities for distance learning in engineering fields

Remote experimentation laboratories are systems based on real equipment, allowing students to perform practical work through a computer connected to the internet. In engineering fields lab activities play a fundamental role. Distance learning has not demonstrated good results in engineering fields because traditional lab activities cannot be covered by this paradigm. These activities can be set for one or for a group of students who work from different locations. All these configurations lead to considering a flexible model that covers all possibilities (for an individual or a group). An inter-continental network of remote laboratories supported by both European and Latin American institutions of higher education has been formed. In this network context, a learning collaborative model for students working from different locations has been defined. The first considerations are presented

A Mobile Portfolio to Support Communities of Practice in Science Education

Online Communities and Social Computing Second International Conference, OCSC 2007, Held as Part of HCI International 2007, Beijing, China, July 22-27, 2007. ProceedingsPractice activities are a key issue for science education students. Typically, these activities are carried out by a community of practice (practicing students and professors) using physical or centralized electronic portfolios. However, these alternatives are limited when the community members need to share the portfolio resources, any time and anywhere. This limitation is also present when support for high interactivity among these persons is required. This paper presents a new kind of portfolio which is able to work in autonomous, client-server, and peer-to-peer manners. This mobile portfolio is fully distributed; therefore, it improves the flexibility to conduct interactions or share portfolio resources among the members of a community of practice. The functionality and stability of the tool have been tested by the developers and the results obtained are encouraging. The use of this distributed portfolio is expected to help science students and professors to enhance practice activities, interactions and interchange of experiences and resources

S-Acyl Thioctic Acid Derivatives in Aerobacter Aerogenes andScenedesmus

1. Acetyl thioctic acid has been prepared chemically and i t s chromatographic and acetylating behavior i s described. 2. A C{sup 14} -containing substance has been found in Scenedesmus, photosynthesizing in the presence of a-C{sup 14}-pyruvate, which has properties suggesting that it i s acetyl thioctic acid. 3 . A C{sup 14}-containing substance has been found in Aerobacter aerogenes, metabolizing a-C{sup 14}-pyruvate, which shows the properties of a labile conjugate of thioctic acid with some relatively polar groups. 4. Acetyl thioctic acid i s formed in vitro when light acts on a solution of thioctic acid and pyruvate

The accretion history of high-mass stars: An ArTéMiS pilot study of Infrared Dark Clouds

The mass growth of protostars is a central element to the determination of fundamental stellar population properties such as the initial mass function. Constraining the accretion history of individual protostars is therefore an important aspect of star formation research. The goal of the study presented here is to determine whether high-mass (proto)stars gain their mass from a compact (<0.1 pc) fixed-mass reservoir of gas, often referred to as dense cores, in which they are embedded, or whether the mass growth of high-mass stars is governed by the dynamical evolution of the parsec-scale clump that typically surrounds them. To achieve this goal, we performed a 350μm continuum mapping of 11 infrared dark clouds, along side some of their neighbouring clumps, with the ArTéMiS camera on APEX. By identifying about 200 compact ArTéMiS sources, and matching them with Herschel Hi-GAL 70μm sources, we have been able to produce mass vs. temperature diagrams. We compare the nature (i.e. starless or protostellar) and location of the ArTéMiS sources in these diagrams with modelled evolutionary tracks of both core-fed and clump-fed accretion scenarios. We argue that the latter provide a better agreement with the observed distribution of high-mass star-forming cores. However, a robust and definitive conclusion on the question of the accretion history of high-mass stars requires larger number statistics

CMB-S4 Science Book, First Edition

This book lays out the scientific goals to be addressed by the next-generation ground-based cosmic microwave background experiment, CMB-S4, envisioned to consist of dedicated telescopes at the South Pole, the high Chilean Atacama plateau and possibly a northern hemisphere site, all equipped with new superconducting cameras. CMB-S4 will dramatically advance cosmological studies by crossing critical thresholds in the search for the B-mode polarization signature of primordial gravitational waves, in the determination of the number and masses of the neutrinos, in the search for evidence of new light relics, in constraining the nature of dark energy, and in testing general relativity on large scales

Green Infrastructure in the Space of Flows: An Urban Metabolism

Recent research demonstrates that urban metabolism studies hold ample scope for informing more sustainable urban planning and design. The assessment of the resource flows that are required to sustain the growth and maintenance of cities can allow gaining a clear picture of how cities operate to comply with environmental performance standards and to ensure that both human and ecosystem health are preserved. Green infrastructure (GI) plays a key role in enhancing both cities’ environmental performance and health. For example, GI interventions mitigate the Urban Heat Island effect (improved thermal comfort), reduce particulate matter concentration (healthier air quality), and sequestrate and store atmospheric carbon (climate change mitigation). Research on ecosystem services and the application of the concept in urban planning provides a growing evidence base that an understanding of provisioning and regulating services can facilitate more environmentally informed GI planning and design. The contribution of GI in enhancing human health and psychological wellbeing is also evidenced in recent studies valuing both material and immaterial benefits provided by urban ecosystems, including cultural ecosystem services. Therefore, the use of ecosystem service frameworks can help reveal and quantify the role of GI in fostering both urban environmental quality and the wellbeing of human populations. However, there remains little discussion of how health and wellbeing aspects can be integrated with environmental performance objectives. In this chapter, urban metabolism thinking is proposed as a way forward, providing analytical tools to inform environmentally-optimized strategies across the urban scales. Opportunities to foster integrated urban metabolism approaches that can inform more holistic GI planning are discussed. Finally, future research avenues to incorporate the multiple dimensions of human health and wellbeing into urban metabolism thinking are highlighted

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

North American monsoon and convectively coupled equatorial waves simulated by IPCC AR4 coupled GCMs

This study evaluates the fidelity of North American monsoon and associated intraseasonal variability in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) coupled general circulation models (CGCMs). Twenty years of monthly precipitation data from each of the 22 models' twentieth-century climate simulations, together with the available daily precipitation data from 12 of them, are analyzed and compared with Global Precipitation Climatology Project (GPCP) monthly and daily precipitation. The authors focus on the seasonal cycle and horizontal pattern of monsoon precipitation in conjunction with the two dominant convectively coupled equatorial wave modes: the eastward-propagating Madden-Julian oscillation (MJO) and the westward-propagating easterly waves. The results show that the IPCC AR4 CGCMs have significant problems and display a wide range of skill in simulating the North American monsoon and associated intraseasonal variability. Most of the models reproduce the monsoon rainbelt, extending from southeast to northwest, and its gradual northward shift in early summer, but overestimate the precipitation over the core monsoon region throughout the seasonal cycle and fail to reproduce the monsoon retreat in the fall. Additionally, most models simulate good westward propagation of the easterly waves, but relatively poor eastward propagation of the MJO and overly weak variances for both the easterly waves and the MJO. There is a tendency for models without undiluted updrafts in their deep convection scheme to produce better MJO propagation.open221

Barriers to Pharmacy-Based Syringe Purchase Among Injection Drug Users in Tijuana, Mexico: A Mixed Methods Study

Injection drug users (IDUs) may be denied purchase of sterile syringes even where purchase without a prescription is legal. This study examined barriers to over-the-counter (OTC) syringe purchase among IDUs in Tijuana, Mexico. A quantitative survey and subsequent focus groups were used to quantify barriers to purchase, identify their correlates and provide in-depth exploration of syringe purchase experiences. Of 627 IDUs, 81% purchased a syringe in the past 6 months and 16% were refused or overcharged. Factors independently associated with refusal/overcharging were homelessness, receptive syringe sharing, >5 uses per syringe, and number of lifetime abscesses. Few pharmacies sold syringes to IDUs, who adapted by limiting purchase attempts to pharmacies known to sell syringes consistently. Failed purchases occurred when drug withdrawal required purchase at unusual times or locations, often following release from jail. IDUs reported syringe sharing, syringe reuse, and searching through unsecured medical waste for syringes in response to failed purchase attempts. Interventions to expand OTC syringe sales to IDUs, particularly near detention facilities, will facilitate safer injection practices