65 research outputs found
Close temporal coupling of neuronal activity and tissue oxygen responses in rodent whisker barrel cortex
Neuronal activity elicits metabolic and vascular responses, during which oxygen is first consumed and then supplied to the tissue via an increase in cerebral blood flow. Understanding the spatial and temporal dynamics of blood and tissue oxygen (To(2)) responses following neuronal activity is crucial for understanding the physiological basis of functional neuroimaging signals. However, our knowledge is limited because previous To(2) measurements have been made at low temporal resolution (>100 ms). Here we recorded To(2) at high temporal resolution (1 ms), simultaneously with co-localized field potentials, at several cortical depths from the whisker region of the somatosensory cortex in anaesthetized rats and mice. Stimulation of the whiskers produced rapid, laminar-specific changes in To(2). Positive To(2) responses (i.e. increases) were observed in the superficial layers within 50 ms of stimulus onset, faster than previously reported. Negative To(2) responses (i.e. decreases) were observed in the deeper layers, with maximal amplitude in layer IV, within 40 ms of stimulus onset. The amplitude of the negative, but not the positive, To(2) response correlated with local field potential amplitude. Disruption of neurovascular coupling, via nitric oxide synthase inhibition, abolished positive To(2) responses to whisker stimulation in the superficial layers and increased negative To(2) responses in all layers. Our data show that To(2) responses occur rapidly following neuronal activity and are laminar dependent
Twenty-first century vaccinomics innovation systems: capacity building in the global South and the role of Product Development Partnerships (PDPs)
The availability of sequence information from publicly available complete genomes and data intensive sciences, together with next-generation sequencing technologies offer substantial promise for innovation in vaccinology and global public health in the beginning of the 21st century. This article presents an innovation analysis for the nascent field of vaccinomics by describing one of the major challenges in this endeavor: the need for capacities in âvaccinomics innovation systemsâ to support the developing countries involved in the creation and testing of new vaccines. In particular, we discuss the need for understanding how institutional frameworks can enhance capacities as intrinsic to a systems approach to health technology development. We focus our attention on the global South, meaning the technically less advanced and developing nations in Africa, Asia, and Latin America. This focus is timely and appropriate because the challenge for innovation in postgenomics medicine is markedly much greater in these regions where basic infrastructures are often underresourced and new or the anticipated institutional relationships can be fragile. Importantly, we examine the role of Product Development Partnerships (PDPs) as a 21st century organizational innovation that contributes to strengthening fragile institutions and capacity building. For vaccinomics innovation systems to stand the test of time in a context of global public health, local communities, knowledge, and cultures need to be collectively taken into account at all stages in programs for vaccinomics-guided vaccine development and delivery in the global South where the public health needs for rational vaccine development are urgent
Managing groundwater supplies subject to drought: perspectives on current status and future priorities from England (UK)
Effective management of groundwater resources during drought is essential. How is groundwater currently managed during droughts, and in the face of environmental change, what should be the future priorities? Four themes are explored, from the perspective of groundwater management in England (UK): (1) integration of drought definitions; (2) enhanced fundamental monitoring; (3) integrated modelling of groundwater in the water cycle; and (4) better information sharing. Whilst these themes are considered in the context of England, globally, they are relevant wherever groundwater is affected by drought
Spin-orbit-driven magnetic structure and excitation in the 5d pyrochlore Cd2Os2O7
Much consideration has been given to the role of spin-orbit coupling (SOC) in 5d oxides,
particularly on the formation of novel electronic states and manifested metal-insulator
transitions (MITs). SOC plays a dominant role in 5d5 iridates (Ir4ĂŸ), undergoing MITs both
concurrent (pyrochlores) and separated (perovskites) from the onset of magnetic order.
However, the role of SOC for other 5d configurations is less clear. For example, 5d3
(Os5ĂŸ) systems are expected to have an orbital singlet with reduced effective SOC. The
pyrochlore Cd2Os2O7 nonetheless exhibits a MIT entwined with magnetic order phenomenologically
similar to pyrochlore iridates. Here, we resolve the magnetic structure in
Cd2Os2O7 with neutron diffraction and then via resonant inelastic X-ray scattering determine
the salient electronic and magnetic energy scales controlling the MIT. In particular, SOC plays
a subtle role in creating the electronic ground state but drives the magnetic order and
emergence of a multiple spin-flip magnetic excitation
Beauty in the Eye of the Home-Owner: Aesthetic Zoning and Residential Property Values
This article empirically confirms one core motivation for architectural zoning: Shape homogeneity among neighboring homes increases the value of residential buildings. Drawing on large-scale shape and transaction data, this study first develops a data-driven measure of architectural similarity, condensing three-dimensional shapes to univariate shape distributions. These algorithm-based similarity estimates are good predictors of human perceptions of shape similarity and are linked to property attributes and transaction prices. For the city of Rotterdam, a price premium of approximately 3.5% is estimated for row houses within very homogeneous ensembles over buildings facing heterogeneous neighbors
A Randomised Trial Evaluating the Safety and Immunogenicity of the Novel Single Oral Dose Typhoid Vaccine M01ZH09 in Healthy Vietnamese Children
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Risk management activities at the DOE Class A reactor facilities
The probabilistic risk assessment (PRA) and risk management group of the Association for Excellence in Reactor Operation (AERO) develops risk management initiatives and standards to improve operation and increase safety of the DOE Class A reactor facilities. Principal risk management applications that have been implemented at each facility are reviewed. The status of a program to develop guidelines for risk management programs at reactor facilities is presented
Hamstring muscles: Architecture and innervation
Knowledge of the anatomical organization of the hamstring muscles is necessary to understand their functions, and to assist in the development of accurate clinical and biomechanical models. The hamstring muscles were examined by dissection in six embalmed human lower limbs with the purpose of clarifying their gross morphology. In addition to obtaining evidence for or against anatomical partitioning ( as based on muscle architecture and pattern of innervation), data pertaining to architectural parameters such as fascicular length, volume, physiological cross-sectional area, and tendon length were collected. For each muscle, relatively consistent patterns of innervation were identified between specimens, and each was unique with respect to anatomical organization. On the basis of muscle architecture, three regions were identified within semimembranosus. However, this was not completely congruent with the pattern of innervation, as a primary nerve branch supplied only two regions, with the third region receiving a secondary branch. Semitendinosus comprised two distinct partitions arranged in series that were divided by a tendinous inscription. A singular muscle nerve or a primary nerve branch innervated each partition. In the biceps femoris long head the two regions were supplied via a primary nerve branch which divided into two primary branches or split into a series of branches. Being the only muscle to cross a single joint, biceps femoris short head consisted of two distinct regions demarcated by fiber direction, with each innervated by a separate muscle nerve. Architecturally, each muscle differed with respect to parameters such as physiological cross-sectional area, fascicular length and volume, but generally all partitions within an individual muscle were similar in fascicular length. The long proximal and distal tendons of these muscles extended into the muscle bellies thereby forming elongated musculotendinous junctions. Copyright (C) 2005 S. Karger AG, Basel
Waste, Industry and Romantic Leisure: Veblen's Theory of Recognition
types: ArticleVeblenâs work contains a neglected, since for the most part implicit, theory of recognition centred on his concepts of waste and workmanship. This article tries to develop this theory in order to shed new light on the theorem of conspicuous leisure and consumption. The legitimacy of violence at the âpredatory stageâ of culture has been partly superseded by a legitimacy of industrial efficiency, so that the leisure classes need to disguise their conspicuous waste as socially useful productive endeavours. At the same time waste remains a powerful symbol of legitimate status, so that even the industrial classes turn to it in order to assert their social worth and demand social recognition. Waste - which is far more central in Veblenâs theory than is emulation - becomes an ambiguous symbol which can stand for both unproductive privilege and industrial efficiency. The utilitarian urge for efficiency and the meaninglessness of a struggle for recognition through conspicuous waste produce a desire for a romantic escape, also acknowledged by Veblen, but often overlooked in his sharp criticism of consumerism
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