212 research outputs found
Effects of prosodically modulated sub-phonetic variation on lexical competition
Eye movements were monitored as participants followed spoken instructions to manipulate one of four objects pictured on a computer screen. Target words occurred in utterance-medial (e.g., Put the cap next to the square) or utterance-final position (e.g., Now click on the cap). Displays consisted of the target picture (e.g., a cap), a monosyllabic competitor picture (e.g., a cat), a polysyllabic competitor picture (e.g., a captain) and a distractor (e.g., a beaker). The relative proportion of fixations to the two types of competitor pictures changed as a function of the position of the target word in the utterance, demonstrating that lexical competition is modulated by prosodically conditioned phonetic variation
Meervoudige overheidssturing in open, dynamische en lerende netwerken, Een essay over de nieuwe rol van het ministerie van Economische Zaken in de energieke netwerksamenleving
Wat betekent het voor een overheid als mensen steeds meer een actieve positie innemen en zelf hun doelen en bijbehorende acties vaststellen, als er horizontale netwerken ontstaan, zonder eenduidig aanspreekpunt of formele representativiteit? Op welke manier kan de overheid in deze context nog sturen? Er is behoefte aan een overheid die meer tussen de mensen komt, die aansluiting zoekt bij de nieuwe dynamiek van de netwerksamenleving, een overheid die bindend vermogen ontwikkelt. Het natuurbeleid (onder meer soortenbeleid en het beleid voor de Ecologische Hoofdstructuur) wordt van oudsher echter vooral gekenmerkt door een hiërarchische wijze van sturing met een grote nadruk op regelgeving. Daarom heeft de directie Natuur & Biodiversiteit aan Alterra Wageningen UR gevraagd om op basis van zowel leerervaringen van eerdere trajecten in het groene domein, als de recente literatuur met betrekking tot de verhouding overheid en netwerksamenleving, een bijdrage te leveren aan de discussie, met als uitgangspunt een aantal simpele vragen: ‘Wat betekent de transitie naar een netwerksamenleving voor de positie en rol van EZ binnen het groene domein? Hoe kan EZ zich effectief bewegen in de netwerksamenleving?
A review of blood transfusions in a trauma unit for young children
Background. Trauma is the leading cause of mortality and morbidity worldwide. Blood transfusions play an incremental role in the acute phase, yet practice varies owing to variations in transfusion thresholds and concerns about potential complications, especially in children.Objectives. To evaluate protocol adherence to blood transfusion thresholds in paediatric trauma patients and determine the degree of blood product wastage, as defined by discarded units.Methods. A retrospective, descriptive study of trauma patients (age 0 - 13 years) who received a blood transfusion in the trauma unit at Red Cross War Memorial Children’s Hospital, Cape Town, South Africa, over a 5.5-year period (1 January 2009 - 1 July 2014). Haemoglobin (Hb) transfusion thresholds were defined as 10 g/dL for neurotrauma patients and patients requiring skin grafting or a musculocutaneous flap (group 1). All other trauma patients had an Hb transfusion threshold of 7 g/dL (group 2).Results. A total of 144 patients were included (mean age 5.2 years (standard deviation (SD) 3.3), 68.1% male). The mean Hb increase after transfusion was 3.5 g/dL (SD 1.7). Adherence to the transfusion Hb threshold protocol was 96.7% for group 1 v. 34.0% for group 2. No complications were reported. Average blood wastage was 3.5 units per year during the study period.Conclusions. Adherence to paediatric blood transfusion protocol was low in the Hb threshold group <7 g/dL. However, transfusion-related complications and wastage were minimal. Further prospective research is required to determine optimal blood transfusion guidelines for paediatric trauma patients
Bacterial evolution: Resistance is a numbers game
Plasmids are well known for spreading antibiotic-resistance genes between bacterial strains. Recent experiments show that they can also act as catalysts for evolutionary innovation, promoting rapid evolution of novel antibiotic resistance
Sequence–function–stability relationships in proteins from datasets of functionally annotated variants: The case of TEM β-lactamases
AbstractA dataset of TEM lactamase variants with different substrate and inhibition profiles was compiled and analyzed. Trends show that loops are the main evolvable regions in these enzymes, gradually accumulating mutations to generate increasingly complex functions. Notably, many mutations present in evolved enzymes are also found in simpler variants, probably originating functional promiscuity. Following a function-stability tradeoff, the increase in functional complexity driven by accumulation of mutations fosters the incorporation of other stability-restoring substitutions, although our analysis suggests they might not be as “global” as generally accepted and seem instead specific to different networks of protein sites. Finally, we show how this dataset can be used to model functional changes in TEMs based on the physicochemical properties of the amino acids
Envelope structure of deeply embedded young stellar objects in the Serpens Molecular Cloud
Aperture synthesis and single-dish (sub) millimeter molecular lines and
continuum observations reveal in great detail the envelope structure of deeply
embedded young stellar objects (SMM1, SMM2, SMM3, SMM4) in the densely
star-forming Serpens Molecular Cloud. Resolved millimeter continuum emission
constrains the density structure to a radial power law with index -2.0 +/- 0.5,
and envelope masses of 8.7, 3.0, and 5.3 M_sol for SMM1, SMM3, and SMM4. The
core SMM2 does not seem to have a central condensation and may not have formed
a star yet. The molecular line observations can be described by the same
envelope model, if an additional, small amount of warm (100 K) material is
included. This probably corresponds to the inner few hundred AU of the envelope
were the temperature is high. In the interferometer beam, the molecular lines
reveal the inner regions of the envelopes, as well as interaction of the
outflow with the surrounding envelope. Bright HCO+ and HCN emission outlines
the cavities, while SiO and SO trace the direct impact of the outflow on
ambient gas. Taken together, these observations provide a first comprehensive
view of the physical and chemical structure of the envelopes of deeply embedded
young stellar objects in a clustered environment on scales between 1000 and
10,000 AU.Comment: 46 pages, incl. 12 postscript figures, uses ApJ latex and psfig
macro
Investigating the Electromechanical Behavior of Unconventionally Ferroelectric Hf0.5Zr0.5O2-Based Capacitors Through Operando Nanobeam X-Ray Diffraction
Understanding various aspects of ferroelectricity in hafnia-based nanomaterials is of vital importance for the development of future nonvolatile memory and logic devices. Here, the unconventional and weak electromechanical response of epitaxial La0.67Sr0.33MnO3/Hf0.5Zr0.5O2/La0.67Sr0.33MnO3 ferroelectric capacitors is investigated, via the sensitivity offered by nanobeam X-ray diffraction experiments during application of electrical bias. It is shown that the pristine rhombohedral phase exhibits a linear piezoelectric effect with piezoelectric coefficient (|d33|) ≈ 0.5–0.8 pmV−1. It is found that the piezoelectric response is suppressed above the coercive voltage. For higher voltages, and with the onset of DC conductivity throughout the capacitor, a second-order effect is observed. The work sheds light into the electromechanical response of rhombohedral Hf0.5Zr0.5O2 and suggests its (un)correlation with ferroelectric switching
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Small States in the Rearview Mirror: Legitimacy in the Management of Economy and Society
Small States in World Markets is about political efficacy and legitimation rather than scoring who is ahead in the economic sweepstakes. Its case for democratic corporatism rests on norms, particularly stability, rather than on narrow measures of economic efficiency. But stability and the efficacious management of the economy and social problems requires a degree of technocracy that undermines the legitimacy of the management process itself by helping to produce populist revolts
Computational Methodologies and Physical Insights into Electronic Energy Transfer in Photosynthetic Light-Harvesting Complexes
We examine computational techniques and methodologies currently in use to
explore electronic excitation energy transfer in the context of
light-harvesting complexes in photosynthetic antenna systems, and comment on
some new insights into the underlying physics. Advantages and pitfalls of these
methodologies are discussed, as are some physical insights into the
photosynthetic dynamics. By combining results from molecular modelling of the
complexes (structural description) with an effective non-equilibrium
statistical description (time evolution), we identify some general features,
regardless of the particular distribution in the protein scaffold, that are
central to light-harvesting dynamics and, that could ultimately be related to
the high efficiency of the overall process. Based on these general common
features, some possible new directions in the field are discussed.Comment: Invited Perspective Article for Phys. Chem. Chem. Phy
A review of blood transfusions in a trauma unit for young children
Background. Trauma is the leading cause of mortality and morbidity worldwide. Blood transfusions play an incremental role in the acute phase, yet practice varies owing to variations in transfusion thresholds and concerns about potential complications, especially in children. Objectives. To evaluate protocol adherence to blood transfusion thresholds in paediatric trauma patients and determine the degree of blood product wastage, as defined by discarded units. Methods. A retrospective, descriptive study of trauma patients (age 0 - 13 years) who received a blood transfusion in the trauma unit at Red Cross War Memorial Children’s Hospital, Cape Town, South Africa, over a 5.5-year period (1 January 2009 - 1 July 2014). Haemoglobin (Hb) transfusion thresholds were defined as 10 g/dL for neurotrauma patients and patients requiring skin grafting or a musculocutaneous flap (group 1). All other trauma patients had an Hb transfusion threshold of 7 g/dL (group 2). Results. A total of 144 patients were included (mean age 5.2 years (standard deviation (SD) 3.3), 68.1% male). The mean Hb increase after transfusion was 3.5 g/dL (SD 1.7). Adherence to the transfusion Hb threshold protocol was 96.7% for group 1 v. 34.0% for group 2. No complications were reported. Average blood wastage was 3.5 units per year during the study period. Conclusions. Adherence to paediatric blood transfusion protocol was low in the Hb threshold group <7 g/dL. However, transfusion-related complications and wastage were minimal. Further prospective research is required to determine optimal blood transfusion guidelines for paediatric trauma patients
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