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1.
J Crit Care ; 30(4): 705-10, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25858820

ABSTRACT

INTRODUCTION: Heart rate complexity, commonly described as a "new vital sign," has shown promise in predicting injury severity, but its use in clinical practice is not yet widely adopted. We previously demonstrated the ability of this noninvasive technology to predict lifesaving interventions (LSIs) in trauma patients. This study was conducted to prospectively evaluate the utility of real-time, automated, noninvasive, instantaneous sample entropy (SampEn) analysis to predict the need for an LSI in a trauma alert population presenting with normal vital signs. METHODS: Prospective enrollment of patients who met criteria for trauma team activation and presented with normal vital signs was conducted at a level I trauma center. High-fidelity electrocardiogram recording was used to calculate SampEn and SD of the normal-to-normal R-R interval (SDNN) continuously in real time for 2 hours with a portable, handheld device. Patients who received an LSI were compared to patients without any intervention (non-LSI). Multivariable analysis was performed to control for differences between the groups. Treating clinicians were blinded to results. RESULTS: Of 129 patients enrolled, 38 (29%) received 136 LSIs within 24 hours of hospital arrival. Initial systolic blood pressure was similar in both groups. Lifesaving intervention patients had a lower Glasgow Coma Scale. The mean SampEn on presentation was 0.7 (0.4-1.2) in the LSI group compared to 1.5 (1.1-2.0) in the non-LSI group (P < .0001). The area under the curve with initial SampEn alone was 0.73 (95% confidence interval [CI], 0.64-0.81) and increased to 0.93 (95% CI, 0.89-0.98) after adding sedation to the model. Sample entropy of less than 0.8 yields sensitivity, specificity, negative predictive value, and positive predictive value of 58%, 86%, 82%, and 65%, respectively, with an overall accuracy of 76% for predicting an LSI. SD of the normal-to-normal R-R interval had no predictive value. CONCLUSIONS: In trauma patients with normal presenting vital signs, decreased SampEn is an independent predictor of the need for LSI. Real-time SampEn analysis may be a useful adjunct to standard vital signs monitoring. Adoption of real-time, instantaneous SampEn monitoring for trauma patients, especially in resource-constrained environments, should be considered.


Subject(s)
Critical Illness , Heart Rate/physiology , Wounds and Injuries/diagnosis , Adult , Blood Pressure/physiology , Case-Control Studies , Electrocardiography , Entropy , Female , Glasgow Coma Scale , Humans , Male , Middle Aged , Prognosis , Prospective Studies , Respiration, Artificial , Sensitivity and Specificity , Trauma Centers , Trauma Severity Indices , Vital Signs , Wounds and Injuries/physiopathology
2.
Opt Express ; 22(2): 1576-93, 2014 Jan 27.
Article in English | MEDLINE | ID: mdl-24515164

ABSTRACT

Quantum Key Distribution (QKD) is maturing quickly. However, the current approaches to its application in optical networks make it an expensive technology. QKD networks deployed to date are designed as a collection of point-to-point, dedicated QKD links where non-neighboring nodes communicate using the trusted repeater paradigm. We propose a novel optical network model in which QKD systems share the communication infrastructure by wavelength multiplexing their quantum and classical signals. The routing is done using optical components within a metropolitan area which allows for a dynamically any-to-any communication scheme. Moreover, it resembles a commercial telecom network, takes advantage of existing infrastructure and utilizes commercial components, allowing for an easy, cost-effective and reliable deployment.

3.
Obes Surg ; 23(3): 279-86, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23135881

ABSTRACT

Roux-en-Y gastric bypass (RYGB) is the gold standard in bariatric surgery. The effect of the procedure is based on restriction, malabsorption and changes in hormonal axis. Ghrelin is an important appetite hormone which is produced mainly in the gastric fundus. By adding a resection of the gastric fundus, we hypothesized that excessive weight loss will be more prominent and the satiety feelings less pronounced compared to standard RYGB. A total of 73 patients with standard very very long limb (VVLL) RYGB (group A) were compared with 44 patients with VVLL RYGB with resection of the fundus (group B). Outcome measures were excessive weight loss (EWL), body mass index (BMI), early postoperative morbidity, change of co-morbidities, and appetite reduction as assessed by an appetite questionnaire over a postoperative period of 24 months. Groups were comparable in basic preoperative descriptions. Additional fundus resection did not influence EWL (group A 66.1 % vs. group B 70.6 %, p = 0.383) or BMI (group A 29 kg/m(2) vs. group B 27 kg/m(2), p = 0.199). No significant difference in morbidity or change of co-morbidities occurred. The appetite and satiety questionnaire showed no difference between group A and group B, respectively. Adding a resection of the gastric fundus in RYGB did not alter the clinical results, i.e., increased excessive weight loss, decrease of appetite, or increase of satiety. The value of removing a part of the ghrelin-producing cells might be overestimated.


Subject(s)
Gastric Bypass , Gastric Fundus/surgery , Ghrelin/metabolism , Laparoscopy/methods , Obesity, Morbid/surgery , Weight Loss , Adult , Appetite , Body Mass Index , Comorbidity , Feeding Behavior , Female , Follow-Up Studies , Gastric Bypass/methods , Gastric Fundus/metabolism , Humans , Male , Obesity, Morbid/epidemiology , Obesity, Morbid/metabolism , Postoperative Complications/epidemiology , Prospective Studies , Satiation , Sleep Apnea Syndromes/epidemiology , Surveys and Questionnaires , Switzerland/epidemiology , Treatment Outcome
4.
Opt Express ; 19(11): 10387-409, 2011 May 23.
Article in English | MEDLINE | ID: mdl-21643295

ABSTRACT

A secure communication network with quantum key distribution in a metropolitan area is reported. Six different QKD systems are integrated into a mesh-type network. GHz-clocked QKD links enable us to demonstrate the world-first secure TV conferencing over a distance of 45km. The network includes a commercial QKD product for long-term stable operation, and application interface to secure mobile phones. Detection of an eavesdropper, rerouting into a secure path, and key relay via trusted nodes are demonstrated in this network.

5.
Water Sci Technol ; 59(1): 149-57, 2009.
Article in English | MEDLINE | ID: mdl-19151497

ABSTRACT

The paper summarises the definition of an extended biokinetic model dedicated to micropollutant degradation in wastewater treatment and the parameter estimation methodology for this model. Additionally it describes results on experimental parameter estimation for two target micropollutants, naphthalene disulfonate (2,6-NDSA) and benzothiazole sulfonic acid (BTSA). Subsequently the parameterised model is applied to real operational data from two laboratory-scale (MBR) installations. The work presents the full chain of theoretical model development, model analysis and practical application to case study data for micropollutants.


Subject(s)
Benzothiazoles/metabolism , Naphthalenesulfonates/metabolism , Sulfonic Acids/metabolism , Waste Disposal, Fluid , Water Pollutants, Chemical/metabolism , Biodegradation, Environmental , Bioreactors , Kinetics , Models, Theoretical
6.
Water Sci Technol ; 50(5): 209-18, 2004.
Article in English | MEDLINE | ID: mdl-15497850

ABSTRACT

This paper deals with the development of a description of membrane bioreactor systems, focussing on wastewater treatment and removal of specific low concentration persistent organic pollutants (e.g. persistent polar pollutants--P3 compounds). In the present work we offer a basic model, adapted to Membrane Bioreactor (MBR) conditions, which reflects the biodegradation of recalcitrant (organic) substances. We put a particular focus on organic aromatic pollutants and demonstrate a model parameter estimation approach, with experiments carried out for linear alkylbenzene sulphonates (LAS).


Subject(s)
Alkanesulfonic Acids/isolation & purification , Bioreactors , Hydrocarbons, Aromatic/isolation & purification , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/isolation & purification , Alkanesulfonic Acids/metabolism , Biodegradation, Environmental , Hydrocarbons, Aromatic/metabolism , Kinetics , Membranes, Artificial , Models, Biological , Waste Disposal, Fluid/instrumentation , Water Pollutants, Chemical/metabolism
7.
Opt Express ; 12(16): 3865-71, 2004 Aug 09.
Article in English | MEDLINE | ID: mdl-19483919

ABSTRACT

We present an entangled-state quantum cryptography system that operated for the first time in a real-world application scenario. The full key generation protocol was performed in real-time between two distributed embedded hardware devices, which were connected by 1.45 km of optical fiber, installed for this experiment in the Vienna sewage system. The generated quantum key was immediately handed over and used by a secure communication application.

8.
Phys Rev Lett ; 75(6): 990-993, 1995 Aug 07.
Article in English | MEDLINE | ID: mdl-10060180
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