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Using a historical institutionalist approach, I demonstrate how institutionalized norms stemming from the liberal tradition in America have informed its language regime by tracing the path dependency of language policy and the critical junctures when changing norms lead to policy shifts. In the early republic, liberal norms enshrined in the Constitution informed a minimalist language regime. At the turn of the 19th century, norms shifted to reflect rapid industrialization and mass immigration, informing attempts at restrictive language policies. At the critical juncture of the civil rights movement, the monolingual language regime was challenged by new norms of what constituted a liberal democratic society. Neoliberal norms of the Reagan presidency facilitated the success of the English-only movement in changing language policies at the state-level. Neoliberal cosmopolitanism of the new millennium re-introduced minimal multilingual policy initiatives. I conclude by suggesting that Trump’s election represents a shift to nationalist, albeit possibly illiberal, norms.
Newspaper text can be broadly divided in the classes ‘opinion’ (editorials, commentary, letters to the editor) and ‘neutral’ (reports). We describe a classification system for performing this separation, which uses a set of linguistically motivated features. Working with various English newspaper corpora, we demonstrate that it significantly outperforms bag-of-lemma and PoS-tag models. We conclude that the linguistic features constitute the best method for achieving robustness against change of newspaper or domain.
Introduction: Reducing the number of patients requiring cardiac monitoring would increase system capacity and improve emergency department (ED) patient flow. The Ottawa Chest Pain Rule helps physicians identify chest pain patients who do not require cardiac monitoring and is based on a ‘normal or non-specific’ ECG and being pain-free on initial physician assessment. Our objective was to measure the impact that the implementation of this decision rule would have on cardiac monitoring bed utilization in adult EDs in Calgary. Methods: A convenience sample of patients was prospectively obtained at each of the four Calgary adult emergency sites. All patients presenting with the Canadian Triage Acuity Scale chief complaint of “cardiac pain”, or “chest pain with cardiac features” were captured for inclusion in the study. Real time interviews and survey assessments were conducted with the primary nurse and physician involved in each patient’s care. Results: A total of 61 patients were captured by the study. Physicians identified cardiac as the primary rule-out pathology in 51% of these patients. The average Heart Score of all study patients was 4.2, and 30% of patients were ultimately admitted. Physicians believed that 39% of the 61 patients needed cardiac monitoring, while primary nurses believed that 59% needed monitoring. Of the 61 patients, 59% were triaged to areas providing cardiac monitoring. The application of the Ottawa Rule would have allowed 47% of patients triaged to cardiac monitoring to be taken off cardiac monitoring. This would translate to a total of greater than 74 hours saved or a reduction of 30% of the total cardiac monitored patient time. Conclusion: The Ottawa rule appears to be a low-risk emergency department flow intervention that has the potential to help reduce resource utilization in emergency departments. This change may result in increased emergency department capacity and improved overall patient flow. This simple rule based only on ECG findings and absence of chest pain can easily be applied and implemented without increasing physician workload or increasing risk to patients.
Our objective is to map dynamic provinces and investigate dynamic changes in Jakobshavn Isbræ, Greenland. We use an approach that combines structural glaciology and remote-sensing data analysis, facilitated by mathematical characterization of generalized spatial surface roughness that provides parameters related to ice dynamics, deformation and interaction of the ice with bed topography. The approach is applied to derive time series of elevation and roughness changes and to attribute changes during rapid retreat. Different dynamic types of fast- and slow-moving ice can be mapped from ICESat Geoscience Laser Altimeter System data (2003–09) and Airborne Topographic Mapper data, using spatial roughness characterization, validated with ASTER and bed-topographic data. Results of comparative analysis of elevation changes and roughness changes of Jakobshavn south ice stream indicate (1) surface lowering of 10–15 m a-1 between 2004 and 2009 and (2) no change in surface roughness and dynamic types. These findings are consistent with a front retreat as part of a fjord-glacier cycle or following warming of fjord water and with climatic warming, but not with an internal dynamic acceleration as a cause of the observed changes during rapid retreat. Relationships to changes in basal water pressure are discussed. All glaciodynamic changes appear to have initiated near the front and propagated up-glacier.
Renewable energy sources – including biomass, geothermal, ocean, solar, and wind energy, as well as hydropower – have a huge potential to provide energy services for the world. The renewable energy resource base is sufficient to meet several times the present world energy demand and potentially even 10 to 100 times this demand. This chapter includes an in-depth examination of technologies to convert these renewable energy sources to energy carriers that can be used to fulfill our energy needs, including their installed capacity, the amount of energy carriers they produced in 2009, the current state of market and technology development, their economic and financial feasibility in 2009 and in the near future, as well as major issues they may face relative to their sustainability or implementation.
Present uses of renewable energy
Since 1990 the energy provided from renewable sources worldwide has risen at an average rate of nearly 2% a year, but in recent years this rate has increased to about 5% annually (see Figure 11.1.) As a result, the global contribution of renewables has increased from about 74 EJ in 2005 to about 89 EJ in 2009 and represents now 17% of global primary energy supply (528 EJ, see Figure 11.2). Most of this renewable energy comes from the traditional use of biomass (about 39 EJ) and larger-scale hydropower (about 30 EJ), while other renewable technologies provided about 20 EJ.
Nanofibers (NFs) of Ga-doped ZnO (GZO) were prepared by electrospinning of polymer–salts solution. Sintering profiles reported in the literature led to loss of the fibrous structure. Hence, the morphology, thermal stability, and phase composition of green and sintered fibers were investigated as function of sintering conditions to elucidate this degradation process. Optimal results were obtained at 400 °C for 30 min. This low temperature sintering of GZO fibers has not been previously reported. The fibers were porous with a significant surface area, making it possible to test their sensitivity to environmental changes. In particular, the response of the GZO NFs to changes in humidity was demonstrated for the first time. The electrical and sensing properties of single NFs prepared at these conditions were studied using a field-effect transistor mode.
Nutrition-related health problems such as obesity are frequent among children and adolescents of Turkish descent living in Germany, yet data on their dietary habits are scarce. One reason might be the lack of validated assessment tools for this target group. We therefore aimed to validate protein and K intakes from one 24 h recall against levels estimated from one 24 h urine sample in children and adolescents of Turkish descent living in Germany.
Cross-sectional analyses comprised estimation of mean differences, Pearson correlation coefficients, cross-classifications and Bland–Altman plots to assess the agreement between the nutritional intake estimated from a single 24 h recall and a single 24 h urine sample collected on the previous day.
Data from forty-three study participants (aged 5–18 years; 26 % overweight) with a traditional Turkish background were included.
The 24 h recall significantly overestimated mean protein and K intake by 10·7 g/d (95 % CI of mean difference: 0·6, 20·7 g/d) and 344 mg/d (95 % CI 8, 680 mg/d), respectively. Correlations between intake estimates were r = 0·25 (P = 0·1) and 0·31 (P = 0·05). Both methods classified 70 % and 69 % of the participants into the same/adjacent quartile of protein and K intake and misclassified 7 % and 7 %, respectively, into the opposite quartile. Bland–Altman plots indicated a wide scattering of differences in both protein and K intake.
Among children and adolescents of traditional Turkish descent living in Germany, one 24 h recall may only be valid for categorizing subjects into high, medium or low consumers.
In this chapter, several applications of hybrid systems theory to benchmark process control problems are described, ranging from logic controller verification for an evaporation system to controller synthesis and optimization-based control of multiproduct batch plants and refrigerator systems.
Introduction to process control applications
While continuous feedback and feedforward control is certainly crucial for the safe, economic, and ecologically benign operation of processing plants of all kinds, the dominant part of the control software for such plants handles and generates signals and events that are discrete in nature. Logic controllers supervise and filter all inputs by the operators for their admissibility, trigger process alarms and partial or complete shut-downs, and switch between control configurations. Sequential controllers govern the start-up of devices, such as pumps and compressors, and of complete units, and the execution of batch recipes as well as shut-down sequences. Even inside continuous controllers, a lot of discrete logic is present, sensors are monitored and their signals are replaced by substitute values in case of errors, the controllers are switched between different modes, anti-windup functions are realized, etc. Exception handling is a major part of all software modules of the control system.
The correct function and economic performance of a plant thus depends on the correct interaction between a vast number of logic and discrete control functions on different layers, the continuous dynamics of the plant, and the continuous or quasicontinuous controllers.
This chapter gives an overview of tools and environments for the modeling, simulation, and optimization of hybrid systems. These tasks are based on different modeling formalisms some of which have already found their way to applications.
Introduction and overview
Although the techniques and tools for the algorithmic analysis and design of hybrid systems that have been presented in the previous chapters have already been applied successfully to a variety of industrial case studies, to this day the dominant industrial tool for computer-based system analysis and design is simulation. The main reason for this lies in the large complexity of many sophisticated technological systems such as cars or chemical plants – an accurate model of a large chemical plant often consists of tens of thousands of nonlinear equations. In addition, such systems may contain hundreds of low-level continuous and logic-based controllers that ensure efficient operation or system safety, and that implement sequential procedures such as production recipes, start-up, or shut-down. For such large-scale hybrid systems, sufficiently accurate piecewise linear or affine abstractions or approximations can often not be determined, or the resulting models are too complex for the application of the techniques described above.
In the last decades, a large number of modeling and simulation tools and environments for hybrid systems have been developed, ranging from rather prototypical academic tools that mostly serve as test beds for hybrid systems research to integrated modeling and simulation environments that are capable of the real-time simulation of highly complex models with tens or even hundreds of thousands of equations using modern computing hardware.
It is now well known that unaffected first-degree relatives of patients with alcohol disorder have electrophysiological abnormalities (less P3 amplitude). These abnormalities are associated with higher scores in impulsivity self-rating scales and are assumed to reflect central nervous system disinhibition and/or hyperexcitability. However very much less is known about the performance of this population in neuropsychological tests assessing executive functioning and in particular the inhibition process.
Thirty-five first-degree relatives of patients with alcohol dependence were compared to thirty-five healthy controls, matched in terms of age, gender and education level. They completed a self-rating scale of impulsiveness (Barratt Impulsiveness Scale) and a battery of neuropsychological tests. The test battery included the Wisconsin Card Sorting Test, a measure of overall executive functioning, and two performance measures of inhibition process (a Stroop task and a Go-No Go task).
As expected, the Barratt Impulsiveness Scale showed differences between the two groups, with first-degree relatives having higher overall scores and increased scores in the non-planning subscale. Results from neuropsychological testing indicated significant differences among the three tasks (WCST, Stroop task and Go-No Go).
Our findings are consistent with the view that unaffected first-degree relatives of patients with alcohol dependence show decrements in executive functioning and inhibition process. Studies are underway to identify genes associated with the underlying predisposition involved in disinhibitory disorders in this population.
To evaluate the reproducibility and workability of the in vivo test model of the European test standard EN 12791 regarding the effectiveness of surgical hand antiseptics and, as a secondary objective, to evaluate the power of the model to discriminate between the effectiveness of various formulations of surgical hand antiseptics.
Prospective, randomized, multicenter study with a Latin square design.
Five laboratories at 2 universities, 2 disinfectant manufacturers, and 1 private testing institution.
Twenty healthy adults in each laboratory.
Surgical hand antisepsis was performed by scrubbing with chlorhexidine gluconate 4% detergent (CHG) or by rubbing the hands with propan-2-OL (70% by volume; Iso 70) or ethanol 85% (E 85); rubbing the hands and forearms for 3 minutes with propan-1-OL (N 60) was used as the reference disinfection procedure. We deliberately chose to use these antiseptics at the given concentrations because they were intended to cover the range of typical antiseptics submitted for approval according to EN 12791.
In once-weekly tests, the immediate effects of the 4 antiseptics were established according to the method laid down in EN 12791 by assessing the release of skin flora from the fingertips as viable bacteria counts per milliliter of sampling fluids before treatment and viable bacteria counts immediately after treatment, separately for both hands, such that after 4 weeks each volunteer had used every formulation once.
The mean log reduction factor (RF) for the release of bacterial skin flora (the log RF was calculated as the log count before treatment minus the log count after treatment) and corresponding standard deviations for the 4 hand antisepsis formulations were as follows: for CHG, 1.1 ± 0.3 colony-forming units (cfu) per milliliter of sampled fluid; for Iso 70, 1.7 ± 0.3 cfu/mL; for E 85, 2.1 ± 0.3 cfu/mL; and for N 60, 2.4 ± 0.4 cfu/mL. The differences between these values proved significant (P<.001) by analysis of variance and in Tukey's “honestly significantly different” (HSD) post hoc test. Although, with regard to their immediate antibacterial activity, the same ranking of these antiseptics was found at all laboratories, the levels of efficacy were significantly different across laboratories (P<.001); no statistical difference was found between left and right hands (P>.01). Relating the log RF values of the other 3 formulations to those of the reference formulation (N 60) abolished differences between laboratories (P = .16); in addition, the interclass correlation coefficient decreased from 9.1% to 4.5%. With 20 volunteers, a minimum difference of 0.47 log between the mean log RFs of the reference formulation and an inferior test formulation will be detected as significant at an α of .05 (1-sided) and a 1 — β value of .8.
The test method described in EN 12791 yielded the same conclusion on the effectiveness of the tested formulations in every laboratory and proved, therefore, reproducible and workable.
Background and objective: Neurological dysfunction is a common problem after cardiac surgery with cardiopulmonary bypass (CPB). Cerebral ischaemia associated with the use of CPB may result in a release of neuronal–ischaemic markers and a subsequent cerebral inflammatory response which may additionally release inflammatory cytokines. In order to locate the origin and to quantify the release of neuronal–ischaemic markers and cytokines we investigated arterial–cerebral venous concentration gradients during and after CPB in a clinical setting.
Methods: In twenty-five patients scheduled for coronary artery bypass grafting surgery we measured the plasma concentration of neuron-specific enolase, S-100β protein as well as interleukins (IL) IL-6, IL-8 and IL-10 from arterial and cerebral venous blood samples prior to surgery (baseline), during hypothermic CPB at 32°C, after termination of bypass, as well as 2, 4 and 6 h after admission to the intensive care unit.
Results: Arterial–cerebral venous concentration gradients of neuron-specific enolase, S-100β, IL-6, IL-8 and IL-10 were neither detectable during nor after CPB. Compared to the baseline period, S-100β and neuron-specific enolase significantly increased during hypothermic CPB. After termination of CPB, neuronal–ischaemic markers as well as cytokines were increased and remained elevated during the investigated time course without reaching baseline values.
Conclusions: Although we found an overall increase in plasma concentrations of neuronal–ischaemic markers, IL-6, IL-8 and IL-10 during and after CPB, arterial–cerebral venous gradients were not detectable for any of these parameters. Our results suggest that the increase of investigated parameters associated with the use of CPB are not primarily caused by a cerebral inflammatory response but rather reflect a release from other sources in the systemic circulation.
Background and objective: The transcerebral double-indicator dilution technique is a recently developed method to measure global cerebral blood flow at bedside. It is based on bolus injection of ice-cold indocyanine green dye and simultaneous recording of resulting thermo- and dye-dilution curves in the aorta and the jugular bulb. However, with this method 40 mL of ice-cold solution is administered as a bolus. Therefore, this prospective clinical study was performed to elucidate the effects of repeated administration of indicator on absolute blood temperature and on cerebral blood flow and metabolism.
Methods: The investigation was performed in nine male patients scheduled for elective coronary artery bypass grafting. Absolute blood temperature was measured in the jugular bulb and in the aorta before and after repeated measurements using the transcerebral double-indicator dilution technique.
Results: During the investigated time course, the blood temperature in the jugular bulb, compared to the aorta, was significantly higher with a mean difference of 0.21°C. The administration of an ice-cold bolus reduced the mean blood temperature by 0.06°C in the jugular bulb as well as in the aorta. After the transcerebral double-indicator dilution measurements a temperature recovery to baseline conditions was not observed during the investigated time period. Cerebral blood flow and cerebral metabolism did not change during the investigated time period.
Conclusions: Repeated measurements with the transcerebral double-indicator dilution technique do not affect absolute jugular bulb blood temperatures negatively. Global cerebral blood flow and metabolism measurements remain unaltered. However, accuracy and resolution of this technique is not high enough to detect the effect of minor changes of physiological variables.
In the metallurgical industry, very few innovative processes reached
the industrial stage. The purpose of this article is to identify the key
principles for monitoring an industrialization process, and to assess
their validity. Mastering the industrialization process is a key to hopefully
succeed in developing efficiently an innovative and competitive process; according
to industry characteristics and past cases of process developments, there might
be a “virtuous” six-step industrialization process for metallurgy; the review
of present industrialization processes within two metallurgical routes tends
to confirm that point.
In November–December 2002, a joint airborne experiment by Centro de Estudios Cientifícos and NASA flew over the Antarctic ice sheet to collect laser altimetry and radio-echo sounding data over glaciers flowing into the Amundsen Sea. A P-3 aircraft on loan from the Chilean Navy made four flights over Pine Island, Thwaites, Pope, Smith and Kohler glaciers, with each flight yielding 1.5–2 hours of data. The thickness measurements reveal that these glaciers flow into deep troughs, which extend far inland, implying a high potential for rapid retreat. Interferometric synthetic aperture radar data (InSAR) and satellite altimetry data from the European Remote-sensing Satellites (ERS-1/-2) show rapid grounding-line retreat and ice thinning of these glaciers. Using the new thickness data, we have reevaluated glacier fluxes and the present state of mass balance, which was previously estimated using ice thicknesses deduced largely from inversion of elevation data assuming hydrostatic equilibrium. The revised total ice discharge of 241 ± 5km3 a–1 exceeds snow accumulation by 81 ± 17 km3 a–1 of ice, equivalent to a sea-level rise of 0.21 ± 0.04 mma–1. This magnitude of ice loss is too large to be caused by atmospheric forcing and implies dynamic thinning of the glaciers. This is confirmed by ice-flow acceleration observed with InSAR. We attribute the flow acceleration and ice thinning to enhanced bottom melting of the ice shelves by a warmer ocean, which reduces buttressing of the glaciers, and in turn accelerates them out of balance.
Background and objective The recently developed transcerebral double-indicator dilution technique has proven to be a feasible monitoring alternative to measure global cerebral blood flow at the bedside. However, the short-term repeatability of transcerebral double-indicator dilution measurements has not yet been investigated. The present study was designed to investigate the accuracy in terms of reliability for repeated transcerebral double-indicator dilution measurements to assess global cerebral blood flow during a definite carbon dioxide challenge in a clinical trial.
Methods The investigation was performed in 10 patients scheduled for elective coronary artery bypass grafting. After induction of anaesthesia, repeated cerebral blood flow measurements using transcerebral double-indicator dilution were performed during target normocapnia, hypocapnia and hypercapnia. For transcerebral double-indicator dilution measurements, a bolus injection of ice-cold indocyanine green was administered into a central vein. The resulting thermal dye dilution curves were recorded simultaneously in the aorta and the jugular bulb using combined fibreoptic thermistor catheters. Cerebral blood flow was calculated from the mean transit times of the indicators through the brain. Additionally, transcranial Doppler sonography was simultaneously performed to measure transient changes in the cerebral blood flow velocity.
Results Transcerebral double-indicator dilution measurements revealed a reasonable coefficient of repeatability with 9.1, 9.7 and 20.2 mL min−1100 g−1 during normo-, hypo- and hypercapnic conditions, respectively. However, a total of 20% of the administered measurements had to be rejected for methodological reasons.
Conclusions Repeated measurements with the transcerebral double-indicator dilution method show a reasonable repeatability. With consideration to the limitations of the transcerebral double-indicator dilution technique, this new method proves to be a reliable monitoring tool to measure global cerebral blood flow at the bedside.
Background and objective Assessment of cardiac preload is of major importance in the management of critically ill patients. Echocardiographic determined left ventricular end-diastolic area and indicator dilution derived intrathoracic blood volume are used as surrogates for cardiac preload. However, no controlled comparison studies on the relationship between induced changes in end-diastolic area and intrathoracic blood volume and concomitant changes in stroke volume index are available.
Methods The effects of a change in body position on these variables were investigated in 10 anaesthetized patients.
Results Intrathoracic blood volume and end-diastolic area decreased by 18 ± 11% and 27 ± 13% respectively. Stroke volume index concomitantly decreased by 19 ± 11%. Correlation analysis revealed a close relation between stroke volume index and intrathoracic blood volume (r = 0.75) and end-diastolic area (r = 0.76).
Conclusions Within the observed range of data, intrathoracic blood volume and end-diastolic area are equivalent indices of cardiac preload.
Research studies clearly indicate that age-related changes in cellular and tissue function are linked to
decreases in the anabolic hormones, growth hormone and insulin-like growth factor (IGF)-1. Although there
has been extensive research on the effects of these hormones on bone and muscle mass, their effect on
cerebrovascular and brain ageing has received little attention. We have also observed that in response to
moderate calorie restriction (a treatment that increases mean and maximal lifespan by 30–40%), age-related
decreases in growth hormone secretion are ameliorated (despite a decline in plasma levels of IGF-1)
suggesting that some of the effects of calorie restriction are mediated by modifying the regulation of the
growth hormone/IGF-1 axis. Recently, we have observed that microvascular density on the surface of the
brain decreases with age and that these vascular changes are ameliorated by moderate calorie restriction.
Analysis of cerebral blood flow paralleled the changes in vasculature in both groups. Administration of
growth hormone for 28 d was also found to increase microvascular density in aged animals and further
analysis indicated that the cerebral vasculature is an important paracrine source of IGF-1 for the brain. In
subsequent studies, administration of GHRH (to increase endogenous release of growth hormone) or direct
administration of IGF-1 was shown to reverse the age-related decline in spatial working and reference
memory. Similarly, antagonism of IGF-1 action in the brains of young animals impaired both learning and
reference memory. Investigation of the mechanisms of action of IGF-1 suggested that this hormone regulates
age-related alterations in NMDA receptor subtypes (e.g. NMDAR2A and R2B). The beneficial role of
growth hormone and IGF-1 in ameliorating vascular and brain ageing are counterbalanced by their well-recognised
roles in age-related pathogenesis. Although research in this area is still evolving, our results
suggest that decreases in growth hormone and IGF-1 with age have both beneficial and deleterious effects.
Furthermore, part of the actions of moderate calorie restriction on tissue function and lifespan may be
mediated through alterations in the growth hormone/IGF-1 axis.
The aim of the present multiple cross-over study was to compare the effects of biphasic positive airway pressure (BIPAP) ventilation with synchronized intermittent mandatory ventilation combined with pressure support ventilation (S-IMV/PSV) in sedated and awake patients after coronary artery bypass grafting (CABG) surgery. Twenty-four patients with no evidence of preoperative respiratory dysfunction and an uncomplicated intraoperative course were investigated. The patients were randomly assigned to one of two groups starting with either BIPAP or S-IMV/PSV mode. Haemodynamic measurements and blood gas analyses were performed during sedation with 2.0 mg kg−1 h−1 propofol in the primary mode, after switching to the alternative ventilatory mode, and in the primary mode again. The same sequence of measurements was repeated in awake patients who had reached extubation criteria. In awake patients, PSV was performed instead of S-IMV. Statistical analysis of data was performed using non-parametric tests. Inspiratory peak pressure increased significantly during S-IMV/PSV in sedated patients in both groups. Other ventilatory parameters did not differ significantly between BIPAP and S-IMV/PSV in both groups. Similarly, haemodynamic parameters and blood-gas analyses did not vary with the ventilatory mode. Our results demonstrate that BIPAP ventilation has comparable effects on haemodynamics and pulmonary gas exchange compared with S-IMV/PSV and PSV when used for short-term ventilatory support in patients after cardiac surgery.