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Some constructs in motivation science are certainly underdeveloped and some motivation researchers may work with underspecified constructs, as suggested by Murayama and Jach (M&J). However, this is not indicative of a general problem in motivation science. Many motivation theories focus on specific mechanisms underlying motivated behavior and thus have already adopted the computational process perspective that M&J call for.
Experimental studies on the sloshing of fluid layers are usually performed in rectangular tanks with fixed boundaries. In contrast, the present study uses a 4.76-m-long circular channel, a geometry with open periodic boundaries. Surface waves are excited by means of a submerged hill that, together with the tank, performs a harmonic oscillation. Laboratory measurements are made using 18 ultrasonic probes, evenly distributed over the channel to track the wave propagation. It is shown that a two-dimensional long-wave numerical model derived via the Kármán–Pohlhausen approach reproduces the experimental data as long as the forcing is monochromatic. The sloshing experiments imply a highly complex surface wave field. Different wave types such as solitary waves, undular bores and antisolitary waves are observed. For order one $\delta _{hill} = h_{hill}/h_0$, where $h_0$ is the mean water level and $h_{hill}$ the obstacle's height, the resonant reflections of solitary waves by the submerged obstacle give rise to an amplitude spectrum for which the main resonance peaks can be explained by linear theory. For smaller $\delta _{hill}$, wave transmissions lead to major differences with respect to the more common cases of sloshing with closed ducts having fully reflective ends for which wave transmission through the end walls is not possible. This ultimately results in more complex resonance diagrams and a pattern formation that changes rather abruptly with the frequency. The experiments are of interest not only for engineering applications but also for tidal flows over bottom topography.
A survey was conducted among Canadian tertiary neonatal intensive care units. Of the 27 sites who responded, 9 did not have any form of antimicrobial stewardship, and 11 used vancomycin for empirical coverage in late-onset-sepsis evaluations. We detected significant variations in the diagnostic criteria for urinary tract infection and ventilator-associated pneumonia.
The unique environment of space is characterized by several stress factors, including intense radiation, microgravity, high vacuum and extreme temperatures, among others. These stress conditions individually or in-combination influence genetics and gene regulation and bring potential evolutionary changes in organisms that would not occur under the Earth's gravity regime (1 × g). Thus, space can be explored to support the emergence of new varieties of microbes and plants, that when selected for, can exhibit increased growth and yield, improved resistance to pathogens, enhanced tolerance to drought, low nutrient and disease, produce new metabolites and others. These properties may be more difficult to achieve using other approaches under 1 × g. This review provides an overview of the space microgravity and ionizing radiation conditions that significantly influence organisms. Changes in the genomics, physiology, phenotype, growth and metabolites of organisms in real and simulated microgravity and radiation conditions are illustrated. Results of space biological experiments show that the space environment has significant scientific, technological and commercial potential. Combined these potentials can help address the future of life on Earth, part of goal e of astrobiology.
The present approach estimates the strength of intensifiers in Dutch by computing their information values in a language corpus, that is, contextual information content (Cohen Priva, 2008; Piantadosi, Tily, & Gibson, 2011) and Shannon Information (Shannon & Weaver, 1948), to respectively explain the use value and the expressive value of intensifiers when they intensify a predicative adjective. Conflicting strength values help in understanding the high number of intensifiers commonly available in particular languages and the constant need for adding new ones. Our approach underlines the relevance of two measures of information content (IC) for ranking intensifiers: (i) IC in context: the more combinatorial or transitional options an intensifier has, the higher its contextual information content and consequently its use value; and (ii) IC in relation to all alternative intensifiers: the higher the surprisal value that the occurrence of an intensifier evokes, the higher its expressive value. We shall investigate the validity of these two measures by researching a large corpus of Dutch tweets and shall test whether the values of these two measures can predict the stacking order in sequences of intensifiers.
After the Portuguese discovered the Cape Verde Islands in AD 1456 they divided its main island, Santiago, into two governing captaincies. The founding settlement in the south-west, Cidade Velha, soon became the Islands’ capital and a thriving trade centre; in contrast, that in the east, Alcatrazes, only lasted as an official seat from 1484–1516 and is held to have ‘failed’ (see Richter 2015).
Dormant states of organisms are easier to store than the living state because they tolerate larger variations in temperature, light, storage space etc., making them attractive for laboratory culture stocks and also for experiments under special circumstances, especially space flight experiments. Like several other organisms, Euglena gracilis is capable of forming desiccation tolerant resting states in order to survive periods of unfavourable environmental conditions. In earlier experiments it was found that dormant Euglena cells must not become completely desiccated. Some residual moisture is required to ensure recovery of the resting states. To analyse the water demand in recovery of Euglena resting states, cells were transferred to a defined amount of cotton wool (0.5 g). Subsequently different volumes of medium (1, 2, 3, 4, 5, 8, 10 and 20 ml) were added in order to supply humidity; a control was set up without additional liquid. Samples were sealed in transparent 50 ml falcon tubes and stored for 9 months under three different conditions:
• Constant low light conditions in a culture chamber at 20°C,
• In a black box, illuminated with short light emitting diode-light pulses provided by joule thieves and
• In darkness in a black box.
After 9 months, cells were transferred to fresh medium and cell number, photosynthetic efficiency and movement behavior was monitored over 3 weeks. It was found that cells recovered under all conditions except in the control, where no medium was supplied. Transcription levels of 21 genes were analysed with a Multiplex-polymerase chain reaction. One hour after rehydration five of these genes were found to be up-regulated: ubiquitin, heat shock proteins HSP70, HSP90, the calcium-sensor protein frequenin and a distinct protein kinase, which is involved in gravitaxis. The results indicate a transient general stress response of the cells.
We welcome the development of a new model on effort and performance and the critique on existing resource-based models. However, considering the vast evidence for the significant impact of experienced task demand on resource allocation, we conclude that Kurzban et al.'s opportunity cost model is only valid for one performance condition: if task demand is unknown or unspecified.
An overview about the German cluster project Cool Silicon aiming at increasing the energy efficiency for semiconductors, communications, sensors and software is presented. Examples for achievements are: 1000 times reduced gate leakage in transistors using high-fc (HKMG) materials compared to conventional poly-gate (SiON) devices at the same technology node; 700 V transistors integrated in standard 0.35 μm CMOS; solar cell efficiencies above 19% at < 200 W/m2 irradiation; 0.99 power factor, 87% efficiency and 0.088 distortion factor for dc supplies; 1 ns synchronization resolution via Ethernet; database accelerators allowing 85% energy savings for servers; adaptive software yielding energy reduction of 73% for e-Commerce applications; processors and corresponding data links with 40% and 70% energy savings, respectively, by adaption of clock frequency and supply voltage in less than 20 ns; clock generator chip with tunable frequency from 83-666 MHz and 0.62-1.6 mW dc power; 90 Gb/s on-chip link over 6 mm and efficiency of 174 fJ/mm; dynamic biasing system doubling efficiency in power amplifiers; 60 GHz BiCMOS frontends with dc power to bandwidth ratio of 0.17 mW/MHz; driver assistance systems reducing energy consumption by 10% in cars
This article studies the issues surrounding the assessment of several home diagnostic tests. First, the authors review the current data and proper use of fecal occult blood and pregnancy tests. Second, they evaluate the roles of blood and urine glucose monitoring in the management of diabetes mellitus and home pressure monitoring in the management of hypertension. The authors conclude that while home measurement of blood pressure or blood sugar can be recommended to improve compliance with medical programs, home fecal occult blood testing, while helpful, has not been fully investigated.
We investigated the effect of seasonality on tree phenology in the tropical montane rain forest of southern Ecuador and analysed possible triggering factors. Two hypotheses were tested: (1) Interspecific synchronization of flowering and fruiting phenology is higher at study sites with pronounced rainfall seasonality compared with sites within perhumid forests. (2) Proximate causes for flowering in closely situated seasonal and perhumid sites are either photoperiodicity or climatic factors. Two nearby study sites with contrasting precipitation patterns were selected at the same altitude east and west of the western Cordillera. Eighty trees from 13 species were observed over a 2.5-y period. Three species were common to both study sites. Phenological and climate data were collected and cross-correlated by conducting a time-series analysis. At the perhumid site, very clear annual patterns of phenological behaviour could be observed for most of the selected rain-forest tree species, but with a poor interspecific synchronization. On the nearby seasonal site in contrast, most species showed high synchrony in their phenological behaviour coinciding with the dry season. There is strong evidence that flowering is induced not by one factor alone: we identified photoperiodic control, radiation and precipitation as possible proximate causes for both sites. Our results confirm studies which state that these factors are closely linked to each other in the tropics.
Microfabricated biochips are developed to continuously monitor cellular phenotype dynamics in a non-invasive manner. In the presented work we describe the novel combination of contact-less micro-dielectric sensors and microfluidics for quantitative cell analysis. The cell chip consists of a polymeric fluidic (PDMS) system bonded to a glass wafer containing the electrodes while temperature and fluid flow are controlled by external heating and pumping stations. Additionally, the cell chip contains an integrated reference arm providing a low-noise detection environment by eliminating background signals and interferences. The high-density interdigitated capacitors (µIDC) are designed to monitor living cells in a space of approximately 10 nL volume by controlling critical electrode characteristics, such as size, shape and passivation composition as well as thickness. The integrated µIDCs are isolated by a 300 nm multi-passivation layer of defined dielectric property and provide non-invasive, stable, robust and non-drifting measurement conditions. The performance of this detector is evaluated using various bacterial, yeast and mammalian cells.
A basic observation is that case-based reasoning has roots in different disciplines: cognitive science, knowledge representation and processing, machine learning and mathematics. As a consequence, there are foundational aspects from each of these areas. We briefly discuss them and comment on the relations between these types of foundations.
This commentary summarizes case-based reasoning (CBR) research applied to image processing. It includes references to the systems, workshops, and landmark publications. Image processing includes a variety of image formats, from computer tomography images to remote sensing and spatial data sets.
This brief article describes the content of the December 2003 issue of MRS Bulletin on New Frontiers in the Application of Neutron Scattering to Materials Science. New techniques, new instrumentation, and new sources are providing exciting opportunities for the use of neutron scattering in materials research at a time when the pace of research and development is accelerating while the complexity of the issues governing materials use is increasing. At a time such as this, it is critical to use the best tool for the job, and neutron scattering is evolving into a tool that can be used with many others, rather than a technique only for the specialist. It is also providing unprecedented resolution in energy to allow the study of the slow dynamics characteristic of many problems in soft matter and to probe surfaces and interfaces in a unique way. In this issue, we have chosen three areas to emphasize these trends: neutron reflectivity as a probe of surfaces and interfaces, the use of neutrons to study complex fluids, and high-resolution neutron scattering studies of dynamics. We also give a view of the future of neutron sources, with an article outlining the opportunities to be provided by sources proposed or under construction in Europe, Japan, and the United States. It is our hope that this sampling of new opportunities in neutron scattering will encourage wider use of these techniques to help solve the challenging materials research problems of today and tomorrow.