91 research outputs found
Differential electrophysiological response during rest, self-referential, and non-self-referential tasks in human posteromedial cortex
The electrophysiological basis for higher brain activity during rest and internally directed cognition within the human default mode network
(DMN) remains largely unknown. Here we use intracranial recordings in
the human posteromedial cortex (PMC), a core node within the DMN,
during conditions of cued rest, autobiographical judgments, and
arithmetic processing. We found a heterogeneous profile of PMC
responses in functional, spatial, and temporal domains. Although the
majority of PMC sites showed increased broad gamma band activity
(30-180 Hz) during rest, some PMC sites, proximal to the retrosplenial
cortex, responded selectively to autobiographical stimuli. However, no
site responded to both conditions, even though they were located within
the boundaries of the DMN identified with resting-state functional
imaging and similarly deactivated during arithmetic processing. These
findings, which provide electrophysiological evidence for heterogeneity
within the core of the DMN, will have important implications for
neuroimaging studies of the DMN
Methane Mitigation:Methods to Reduce Emissions, on the Path to the Paris Agreement
The atmospheric methane burden is increasing rapidly, contrary to pathways compatible with the goals of the 2015 United Nations Framework Convention on Climate Change Paris Agreement. Urgent action is required to bring methane back to a pathway more in line with the Paris goals. Emission reduction from âtractableâ (easier to mitigate) anthropogenic sources such as the fossil fuel industries and landfills is being much facilitated by technical advances in the past decade, which have radically improved our ability to locate, identify, quantify, and reduce emissions. Measures to reduce emissions from âintractableâ (harder to mitigate) anthropogenic sources such as agriculture and biomass burning have received less attention and are also becoming more feasible, including removal from elevated-methane ambient air near to sources. The wider effort to use microbiological and dietary intervention to reduce emissions from cattle (and humans) is not addressed in detail in this essentially geophysical review. Though they cannot replace the need to reach ânet-zeroâ emissions of CO2, significant reductions in the methane burden will ease the timescales needed to reach required CO2 reduction targets for any particular future temperature limit. There is no single magic bullet, but implementation of a wide array of mitigation and emission reduction strategies could substantially cut the global methane burden, at a cost that is relatively low compared to the parallel and necessary measures to reduce CO2, and thereby reduce the atmospheric methane burden back toward pathways consistent with the goals of the Paris Agreement
Suppression of the 2010 Alexandrium fundyense bloom by changes in physical, biological, and chemical properties of the Gulf of Maine
Author Posting. © American Society of Limnology and Oceanography, 2011. This article is posted here by permission of American Society of Limnology and Oceanography for personal use, not for redistribution. The definitive version was published in Limnology and Oceanography 56 (2011): 2411-2426, doi:10.4319/lo.2011.56.6.2411.For the period 2005â2009, the abundance of resting cysts in bottom sediments from the preceding autumn was a first-order predictor of the overall severity of springâsummer blooms of Alexandrium fundyense in the western Gulf of Maine and southern New England. Cyst abundance off mid-coast Maine was significantly higher in autumn 2009 than it was preceding a major regional bloom in 2005. A seasonal ensemble forecast was computed using a range of forcing conditions for the period 2004â2009, suggesting that a large bloom was likely in the western Gulf of Maine in 2010. This did not materialize, perhaps because environmental conditions in springâsummer 2010 were not favorable for growth of A. fundyense. Water mass anomalies indicate a regional-scale change in circulation with direct influence on A. fundyense's niche. Specifically, near-surface waters were warmer, fresher, more stratified, and had lower nutrients than during the period of observations used to construct the ensemble forecast. Moreover, a weaker-than-normal coastal current lessened A. fundyense transport into the western Gulf of Maine and Massachusetts Bay. Satellite ocean color observations indicate the 2010 spring phytoplankton bloom was more intense than usual. Early season nutrient depletion may have caused a temporal mismatch with A. fundyense's endogenous clock that regulates the timing of cyst germination. These findings highlight the difficulties of ecological forecasting in a changing oceanographic environment, and underscore the need for a sustained observational network to drive such forecasts.We gratefully acknowledge support of the National Oceanic
Atmospheric Administration (grant NA06NOS4780245 for the
Gulf of Maine Toxicity (GOMTOX) program) and the Woods
Hole Center for Oceans and Human Health through National
Science Foundation grants OCE-0430724 and OCE-0911031 and
National Institute of Environmental Health Sciences grant 1P50-
ES01274201
A red tide of Alexandrium fundyense in the Gulf of Maine
Author Posting. © The Author(s), 2013. This is the author's version of the work. It is posted here by permission of Elsevier for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part II: Topical Studies in Oceanography 103 (2014): 174-184, doi:10.1016/j.dsr2.2013.05.011.In early July 2009, an unusually high concentration of the toxic dinoflagellate
Alexandrium fundyense occurred in the western Gulf of Maine, causing surface waters to appear
reddish brown to the human eye. The discolored water appeared to be the southern terminus of a
large-scale event that caused shellfish toxicity along the entire coast of Maine to the Canadian
border. Rapid-response shipboard sampling efforts together with satellite data suggest the water
discoloration in the western Gulf of Maine was a highly ephemeral feature of less than two
weeks in duration. Flow cytometric analysis of surface samples from the red water indicated the
population was undergoing sexual reproduction. Cyst fluxes downstream of the discolored water
were the highest ever measured in the Gulf of Maine, and a large deposit of new cysts was
observed that fall. Although the mechanisms causing this event remain unknown, its timing
coincided with an anomalous period of downwelling-favorable winds that could have played a
role in aggregating upward-swimming cells. Regardless of the underlying causes, this event
highlights the importance of short-term episodic phenomena on regional population dynamics of
A. fundyense.The R/V Tioga sampling effort was facilitated by event response funding from the
National Oceanic Atmospheric Administration (NOAA), National Ocean Service, Center for
Sponsored Coastal Ocean Research, through NOAA Cooperative Agreement NA17RJ1223.
Additional support for follow-up analysis and synthesis was provided by NOAA grant
NA06NOS4780245 for the Gulf of Maine Toxicity (GOMTOX) program and the Woods Hole
Center for Oceans and Human Health through National Science Foundation grants OCE-
0430724 and OCE-0911031 and National Institute of Environmental Health Sciences grant
1P50-ES01274201
Observations of storm-induced mixing and Gulf Stream Ring incursion over the southern flank of Georges Bank : winter and summer 1997
Author Posting. © American Geophysical Union, 2010. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 115 (2010): C08008, doi:10.1029/2009JC005706.High-resolution hydrographic measurements collected along the southern edge of Georges Bank during March and JuneâJuly 1997 focused on characterizing processes that drive fluxes of material between the slope and bank. Wintertime sampling characterized changes driven by a strong storm. A Scotian Shelf crossover event produced a ribbon of anomalously fresh water along the bank's southern flank that was diluted during the storm. Comparison of prestorm and poststorm sections shows that over the bank changes in heat and salt inventories are consistent with those expected solely from local surface fluxes. In deeper waters, advective effects, likely associated with frontal motion and eddies, are clearly important. Summertime surveys resolve the development of a massive intrusion of Gulf Stream-like waters onto the bank. East of the intrusion, a thin extrusion of bank water is drawn outward by the developing ring, exporting fresher water at a rate of about 7 Ă 104 m3/s. A large-amplitude Gulf Stream meander appears to initiate the extrusion, but it quickly evolves, near the bank edge, into a warm core ring. Ring water intrudes to approximately the 80 m isobath, 40 km inshore from the bank edge. The intrusion process seems analogous to the development of Gulf Stream shingles (a hydrodynamic instability) in the South Atlantic Bight. It appears that, once the intruded water is established on the bank, it remains there and dissipates in place. Although the intrusion is an extremely dramatic event, it is probably not actually a major contributor to shelf edge exchanges over a seasonal time scale.This work was supported by the National Science Foundation as part of the U.S. Global Ocean Ecosystems Dynamics (GLOBEC) program through grant OCE-9632349. Lee received additional support from OCE-0628379
Motion and Form Coherence Detection in Autistic Spectrum Disorder: Relationship to Motor Control and 2:4 Digit Ratio
Health economists, tobacco control and international development: On the economisation of global health beyond neoliberal structural adjustment policies
New genetic loci link adipose and insulin biology to body fat distribution.
Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (PÂ <Â 5Â ĂÂ 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms
Theorizing technologically mediated policing in smart cities: an ethnographic approach to sensing infrastructures in security practices
Smart digital infrastructures predicated on myriads of sensors distributed in the environment are often rendered as key to contemporary urban security governance to detect risky or suspicious entities before or during a criminal event takes place. At the same time, they often involve surveillance of urban environments, and thus not only criminals but also large groups of people and entities unrelated to criminal phenomena can end up under close inspection.This chapter makes its contribution on two levels. For one, it offers a theoretical framework to the research and conceptualization of the role of sensing infrastructures in urban security practices. It shows how insights from Philosophy of Technology and Science and Technology Studies can produce a nuanced understanding of the role of digital technologies in security practices, beyond standard conceptualizations of technology. Moreover, the chapter proposes a geological approach to enrich our repertoire of imagining and researching smart urban ecosystems.Secondly, the chapter contributes to a higher level of transparency of these practices by presenting the results of ethnographic research performed in a set of police organizations that employ sensing infrastructures and algorithmic profiling in their practices. The chapter draws empirically on research performed in the Dutch police, both at municipal and national levels with some additional material gathered in a constabulary in England. In these organizations, resource allocation decisions are often predicated on automated number plate recognition technology that processes data from an array of smart cameras distributed in the environment. In these ways together, the chapter highlights a set of normative issues with implications for the effectiveness and legitimacy of urban security (surveillance) practices in smart environments. Security and Global Affair
Changing perspectives on the internationalization of R&D and innovation by multinational enterprises: a review of the literature
Internationalization of R&D and innovation by Multinational Enterprises (MNEs) has undergone a gradual and comprehensive change in perspective over the past 50 years. From sporadic works in the late 1950s and in the 1960s, it became a systematically analysed topic in the 1970s, starting with pioneering reports and âfoundation textsâ. Our review unfolds the theoretical and empirical evolution of the literature from dyadic interpretations of centralization versus decentralization of R&D by MNEs to more comprehensive frameworks, wherein established MNEs from Advanced Economies still play a pivotal role, but new players and places also emerge in the global generation and diffusion of knowledge. Hence views of R&D internationalization increasingly rely on concepts, ideas and methods from IB and other related disciplines such as industrial organization, international economics and economic geography. Two main findings are highlighted. First, scholarly research pays an increasing attention to the network-like characteristics of international R&D activities. Second, different streams of literature have emphasized the role of location- specific factors in R&D internationalization. The increasing emphasis on these aspects has created new research opportunities in some key areas, including inter alia: cross-border knowledge sourcing strategies, changes in the geography of R&D and innovation, and the international fragmentation of production and R&D activities
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