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Direct intra-abdominal pressure monitoring via piezoresistive pressure measurement: a technical note

Direct intra-abdominal pressure monitoring via piezoresistive pressure measurement: a technical note

regard [4-6]. But it has inherent problems with regard to intrinsic bladder wall tension, reference level [7], body position, discontinuity and indirectness [8]. In a previously described porcine model two different devices capable of automatic continuous piezoresistive pressure reading measurement (PRM) were used for direct IAP measurement. Both, a probe to be connected to a handheld reading device and the other with the ability to perform a reset to the atmospheric pressure showed a high precision and a good agreement with bladder pressure measurement[9,10]. Although direct intraabdominal pressure measurement is routinely used to validate indi- rect methods [11-14] it has not yet been systematically evaluated whether these PRM techniques can be per- formed safely and reliably in the postoperative monitor- ing of patients.
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Continuous wrist blood pressure measurement with ultrasound

Continuous wrist blood pressure measurement with ultrasound

A new method for blood pressure measurement uses the radial artery at the wrist. The measurement principle is based on the R IVA -R OCCI and the P EŇÁZ principle [3]. In the R IVA -R OCCI method a cuff is used to compress the upper arm arteries and measure the blood pressure by detecting the pulsation of blood through the vessel. In contrast to the traditional measurement, a small pressure balloon occludes the radial artery on the wrist. The radial artery is a small, superficial artery where only a small volume is needed to occlude the blood flow making the method more comfortable for the patient.
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Direct intra-abdominal pressure monitoring via piezoresistive pressure measurement: a technical note

Direct intra-abdominal pressure monitoring via piezoresistive pressure measurement: a technical note

regard [4-6]. But it has inherent problems with regard to intrinsic bladder wall tension, reference level [7], body position, discontinuity and indirectness [8]. In a previously described porcine model two different devices capable of automatic continuous piezoresistive pressure reading measurement (PRM) were used for direct IAP measurement. Both, a probe to be connected to a handheld reading device and the other with the ability to perform a reset to the atmospheric pressure showed a high precision and a good agreement with bladder pressure measurement[9,10]. Although direct intraabdominal pressure measurement is routinely used to validate indi- rect methods [11-14] it has not yet been systematically evaluated whether these PRM techniques can be per- formed safely and reliably in the postoperative monitor- ing of patients.
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Disagreement of the two oscillometric blood pressure measurement devices, Datascope Accutorr Plus and Omron HEM-705CP II, and bidirectional conversion of blood pressure values.

Disagreement of the two oscillometric blood pressure measurement devices, Datascope Accutorr Plus and Omron HEM-705CP II, and bidirectional conversion of blood pressure values.

Disagreement of the two oscillometric blood pressure measurement devices, Datascope Accutorr Plus and Omron HEM-705CP II, and bidirectional conversion of blood pressure values (2014) B[r]

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Effect of blood pressure and total
cholesterol measurement on risk prediction
using the Systematic COronary Risk
Evaluation (SCORE)

Effect of blood pressure and total cholesterol measurement on risk prediction using the Systematic COronary Risk Evaluation (SCORE)

Measures Self-reported data on sex, age and current smoking status were collected within the SP. TC and BP were assessed during both, the SP and the EP. TC was determined from blood samples using standard methodology at the Institute of Clinical Chemistry at the University Medicine Greifs- wald. A single blood pressure reading of the right arm in the seated position was taken during the SP. During the EP, blood pressure measurement was performed according to a standardized protocol by a certified nurse [ 12 ]. The first reading was taken after a 5-min rest. In total, three readings of the right arm and one reading of the left arm were taken at 3-min intervals. For all blood pressure mea- surements, an Omron 705IT blood pressure monitor (Omron Corporation, Tokyo, Japan) was used.
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Clinical evaluation of an air-capsule technique for the direct measurement of intra-abdominal pressure after elective abdominal surgery

Clinical evaluation of an air-capsule technique for the direct measurement of intra-abdominal pressure after elective abdominal surgery

Conclusion Direct, intraabdominal measurement of IAP was safely performed in 30 patients after elective abdominal surgery for up to 5 days. Beeing aware of relatively low pressure ranges (<17 mmHg), agreement with standard IVP was acceptable in the underlaying study. Direct measurement could be indicated in patients after abdominal surgery who are at risk for the development of IAH e.g. after liver- transplantation, after decompression for ACS and prior to closure of abdominal walls after laparostomy. Although direct intraabdominal pressure measurement appears to be feasible in selected surgical patients, prospective clini- cal studies are needed to confirm IAP thresholds already known from bladder pressure measurement.
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Clinical evaluation of an air-capsule technique for the direct measurement of intra-abdominal pressure after elective abdominal surgery

Clinical evaluation of an air-capsule technique for the direct measurement of intra-abdominal pressure after elective abdominal surgery

The amount of measurement volume has also been ques- tioned [26]. Malbrain and De Waele investigated the effect of measurement volume on bladder pressure and observed a significant increase with a volume of 25 ml. In the investigation of Malbrain, the increase of IVP only became clinically relevant at a volume of 75 ml for most of the patients and it was concluded that larger instillation volumes than the usually recommended 50 ml to estimate IAP by bladder pressure may cause clinically relevant over- estimation of IAP. Kimball recently published a study in which bladder pressure measurement in critically ill patients using 50 ml displayed high reproducibility and reliability [27]. Consequently, the 50 ml used as measure- ment volume for IVP in the patients of the underlying study appear to be appropriate.
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Contextual analysis of the measurement of blood pressure in clinical practice

Contextual analysis of the measurement of blood pressure in clinical practice

After more than a century, the indirect method with auscultatory technique is the most used resource for blood pressure measurement in clinical practice. The mercury manometers are considered the most reliable in any comparison made experimentally with other instruments. However, the day-to-day, aneroid devices are mostly used due to its lower price and size, despite showing lower accuracy. For this reason, it is important that certain precautions are observed, in order to increase confidence in the values found using these devices. 4
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Telemetric Measurement of Intraocular Pressure via an Implantable Pressure Sensor—12-Month Results from the ARGOS-02 Trial

Telemetric Measurement of Intraocular Pressure via an Implantable Pressure Sensor—12-Month Results from the ARGOS-02 Trial

measurements during a 1-year period, despite the absence of reminders. In recent years, a number of devices have been intro- duced that attempt to address either 24-hour monitoring (ie, a contact lens–based method that measures changes in the corneal curvature thought to represent changes in IOP) 18 or self-measurement (ie, a rebound tonometer that does not require topical anesthetics and is designed to be operated by the patient himself). 19 , 20 Although both devices are significant advances toward a better un- derstanding of IOP dynamics, they still have limitations in terms of usability, data interpretation, and dependence on corneal parameters. The contact lens sensor, for instance, although relatively noninvasive and with quasi- continuous measurements for up to 24 hours, currently cannot be directly calibrated to other tonometry methods and it is, therefore, unclear how its measurements corre- spond to changes in IOP. 21 In contrast, the rebound tonometer enables self-measurement but is not capable of automatic measurements over extended periods of time. It is useful, however, for obtaining IOP measurements outside of normal office hours and has been successfully used this way in a number of clinical studies. Its limitations lie in restriction of the measurements to an upright (seated) position and open eyes, as well as the fact that the device is not easy to operate. Only about 74% of all study subjects (with a positive selection bias toward patients interested in using the device) were able to successfully self-measure IOP, while the remaining quarter could not properly handle the device despite extensive training. 19 Most important, it does not provide IOP measurements during sleep.
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Empirical spectral model of wall pressure fluctuations including adverse pressure gradient effects

Empirical spectral model of wall pressure fluctuations including adverse pressure gradient effects

those experiments were realized on dierent plate model setups and airfoils. A review of the existing spectral models for adverse pressure gradient boundary layers is given and predictions of those models are compared to the experimental results. Hu and Herr's model is used as the basis for developing the present model. One of the major dierences between Hu and Herr's model and the others is the use of the boundary layer shape factor to evaluate the spectral change at mid-frequencies instead of Clauser's equilibrium parameter. An improvement of the predicted spectral peak location and the respective peak level is made using the present model and its broadband predictions compare well with the experimental results.
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European integration under pressure

European integration under pressure

E conomic troughs are not a good time for economic integration. Any initiative for more integration in goods and capital markets by reducing tariffs and, more importantly, non-tariff barriers to trade, not to speak of allowing more migration, is futile at a time when countries feel economic pressure. Consequently, Germany’s enthusiasm for European in- tegration has been more than muted recently. Given the dire straits in which the German economy fi nds itself, Chancellor Schröder has distinguished himself as a very outspoken opponent of attempts by Brussels to bring more of the common market to Germany. (It should not be forgotten that Germany is among those bringing up the rear not only in terms of economic growth but also in terms of implementing European law and directives.)
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Bargaining under Time Pressure

Bargaining under Time Pressure

CESifo Working Paper No. 5685 Bargaining under Time Pressure Abstract We experimentally investigate the effect of time pressure in a rich-context, unstructured bargaining game with earned status and competing reference points. Our results show that average opening proposals, concessions, and agreed shares are very similar across different levels of time pressure. Nevertheless, as predicted, time pressure systematically influenced agreements. In particular, the likelihood of bargainers reaching the explicit reference point outcome in agreements increases with time pressure, and the likelihood of reaching the implicit reference point (equal division) in agreements decreases with time pressure. Disagreement rates and the frequency of last-moment agreements are strongly affected: the disagreement rate rises dramatically with time pressure, and last-moment agreements are significantly more frequent. This effect is explained by a stronger connection between the tension in first proposals and the final bargaining outcome under time pressure than without time pressure.
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Bargaining under time pressure

Bargaining under time pressure

In determining the deadlines for LTP and HTP, we are mainly concerned about two things: (i) the time pressure in HTP should not be excessive; subjects should still have some time to be able to exchange enough offers and counter-offers and be able to exchange at least short messages; and (ii) the deadline in LTP should not be too loose; if the time for bargaining in LTP constitutes a large portion of the total time spent in the lab, this may cause problems (e.g., boredom). In line with these considerations, we implemented 90 seconds for HTP and 10 minutes for LTP. These values lie well within the set of period lengths used in earlier studies that investigate time pressure effects on bargaining (for high time pressure, between 15 seconds and 90 seconds, and for low time pressure between 180 seconds and 30 minutes). Notice that there is only one bargaining round and no repetitions.
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Pressure ulcers assissment through the pressure ulcer scale for healing application (PUSH)

Pressure ulcers assissment through the pressure ulcer scale for healing application (PUSH)

Objective: To assess pressure ulcers(PU) with focus on the PUSH scale application. Methods:It is a prospective longitudinal study, performed between September and October 2010, in the three Intensive Care Units (ICUs) of a hospital in Teresina city, with sample of 19 patients and 134 PUSH applications, non-probabilist by convenience. Results: it was featured by the predominance of PU in females(52,6%), aged ≥ 80years old(36,8%) and mixed color (52,6%); the main caregivers were their grown-up children (73,7%). All patients had bladder probe, bowel incontinence and bed restriction with an average of 1,18 years(±5,18). Such limitations in 73,68% were caused by the underlying disease, being that 84,2% of them were unaware. PUs prevalence was of 61,29%, from which 63,33% were in the sacral region, stage II, being that 29,6% of them were treated with AGE oil. The EFA was the predominant coverage(29.6%).There was a decline or maintenance of the scale scores. Conclusions:The PUSH scale is useful in the wound scarring, by allowing monitoring global results and being presented as valid to integrate protocols, in order to implement the nursing care. Descriptors: Nursing, Pressure ulcers, Measurment tools. RESUMO
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Studying under time-pressure

Studying under time-pressure

outside the classroom Total time invested without breaks or travelling to university Total time invested with breaks and travelling to university Paid work Average for all. SOEP 2008 [r]

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Under Pressure: Mit Konzernklagen gegen Umweltschutz

Under Pressure: Mit Konzernklagen gegen Umweltschutz

Die Klauseln zu „fairer und gerechter Behandlung“ und „(indirekter) Enteignung“ auf die sich Lone Pine bei seiner Klage bezieht, wären durch den geplanten Multilateralen Investitions[r]

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Azeotropic Pressure Swing Distillation

Azeotropic Pressure Swing Distillation

discussed in chapter 6. As well as for the continuous process the process control concepts and the process designs will be discussed and analyzed. The main improvement in inverted batch design is the introduction of the advanced batch structure. Furthermore the start-up of the batch processes is discussed. The focus lies here in the automatic switching of the controllers. The different batch design concepts will be compared in a simulations study using an analytical as well as the rigorous dynamic model. The comparison of both concepts, the continuous and the discontinuous process follows in chapter 7. The potential of the heat integration discussed for the pressure swing distillation leads to the idea to uses this concept with other unit operation as well. So in the last chapter 8 a new way of using an energy integration concept for a Hybrid- process composed of a distillation and a pervaporation unit will be introduced, including a first feasibility study, also for the example of the homogenous azeotropic mixture acetonitrile / water as an alternative process concept to the pressure swing distillation process mainly discussed in this work. Finally in chapter 9 a summary of all results and an outlook for further studies in the range of azeotropic separation is given.
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Quenchable High Pressure Phases of DyYbSs High Pressure Phases, Crystal Structures 

Quenchable High Pressure Phases of DyYbSs High Pressure Phases, Crystal Structures 

This work has been digitalized and published in 2013 by Verlag Zeitschrift für Naturforschung in cooperation with the Max Planck Society for the Advancement of Science under a Creative[r]

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The pressure resistance of hollow glass fibers at internal pressure load

The pressure resistance of hollow glass fibers at internal pressure load

The distribution of defects in or on the fibers seems to have an important role in that behavior. It can be assumed that the low burst pressures within each test series are caused by test samples with bigger or a high number of defects. Such defects led to stress peaks inside the fiber and caused the breakage. Consequently, test samples with higher burst pressures could exhibit smaller defects or, respectively, a lower number of defects. Hydrolytic reactions on the surface could have influenced the characteristics of the flaws especially of the smaller ones. The edges of defects could be rounded by the hydrolytic reaction on the surface and therefore possible stress peaks under inner pressure could be mitigated or removed [176]. Due to the constant air moisture the hydrolytic reaction featured a higher intensity than in alterable moisture [94]. The decreasing failure probability of samples stored at defined concentration at higher internal pressure in comparison to new fibers could be an indication for this assumption. Therefore borosilicate fibers with small flaws or a low number of defects could withstand higher pressures after being stored in constant air moistures. Bigger flaws were rounded and changed by the chemical reaction as well. Because of the size or the depth a positive influence were not possible.
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On Pressure-Actuated Cellular Structures

On Pressure-Actuated Cellular Structures

than 1𝑒-5 𝜕𝛱/𝜕𝑢 of residual energy potential at each rotational DOF, the number of the necessary optimization iterations for convergence is extremely reduced from 2,000 to 20,000 in the underlying publications to about ten, depending on the Young’s modulus of the material. This is basically enabled by the coupling of dependencies between independent state variables in the sensitivity matrix. Especially for increased model complexity, the effects of this enhancement are significant. On the basis of the same model, the simulation of the resulting structure for varied load conditions is achieved by using a changed set of optimization parameters. In contrary to the shape-optimization process, the global potential energy of the structure is reduced by the variation of only rotational DOFs. The cell side lengths are kept constant. For varying load sets, the characterization of the structure regarding its deformation behaviour and stiffness against external loads is investigated. The three pressure-dependent phases, deformation, transition and stiffening can be observed. Also the load-dependent structural stresses can be evaluated in the characterization step. Factors of influence like the shape of the cell, the hinge and cell side geometry, the material, the manufacturing and target shapes and the external loads are identified and related to the resulting effects on the structural characteristics and deformation behaviour.
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