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Monitors
Selected AbstractsALPINE AREAS IN THE COLORADO FRONT RANGE AS MONITORS OF CLIMATE CHANGE AND ECOSYSTEM RESPONSE,GEOGRAPHICAL REVIEW, Issue 2 2002MARK W. WILLIAMS ABSTRACT. The presence of a seasonal snowpack in alpine environments can amplify climate signals. A conceptual model is developed for the response of alpine ecosystems in temperate, midlatitude areas to changes in energy, chemicals, and water, based on a case study from Green Lakes Valley,Niwot Ridge, a headwater catchment in the Colorado Front Range. A linear regression shows the increase in annual precipitation of about 300 millimeters from 1951 to 1996 to be significant. Most of the precipitation increase has occurred since 1967. The annual deposition of inorganic nitrogen in wetfall at the Niwot Ridge National Atmospheric Deposition Program site roughly doubled between 1985,1988 and 1989,1992. Storage and release of strong acid anions, such as those from the seasonal snowpack in an ionic pulse, have resulted in episodic acidification of surface waters. These biochemical changes alter the quantity and quality of organic matter in high-elevation catchments of the Rocky Mountains. Affecting the bottom of the food chain, the increase in nitrogen deposition may be partly responsible for the current decline of bighorn sheep in the Rocky Mountains. [source] A robust monitor construct with runtime fault detection,CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 5 2006Jiannong Cao Abstract The monitor concept provides a structured and flexible high-level programming construct to control concurrent accesses to shared resources. It has been widely used in a concurrent programming environment for implicitly ensuring mutual exclusion and explicitly achieving process synchronization. This paper proposes an extension to the monitor construct for detecting runtime errors in monitor operations. Monitors are studied and classified according to their functional characteristics. A taxonomy of concurrency control faults over a monitor is then defined. The concepts of a monitor event sequence and a monitor state sequence provide a uniform approach to history information recording and fault detection. Rules for detecting various types of faults are defined. Based on these rules, fault-detection algorithms are developed. A prototypical implementation of the proposed monitor construct with runtime fault detection mechanisms has been developed in Java. We shall briefly report our experience with and the evaluation of the robust monitor prototype. Copyright © 2005 John Wiley & Sons, Ltd. [source] Hourly surface wind monitor consistency checking over an extended observation periodENVIRONMETRICS, Issue 4 2009Scott Beaver Abstract A consistency checking methodology is presented to aid in identifying biased values in extended historical records of hourly surface wind measurements obtained from a single station. The method is intended for screening extended observation periods for values which do not fail physical consistency checks (i.e., standard or complex quality assurance methods), yet nonetheless exhibit statistical properties which differ from the bulk of the record. Several specific types of inconsistencies common in surface wind monitoring datasets are considered: annual biases, unexpected values, and discontinuities. The purely empirical method checks for self-consistency in the temporal distribution of the wind measurements by explicitly modeling the diurnal variability. Each year of data is modeled using principal component analysis (PCA) (or empirical orthogonal functions, EOF), then hierarchical clustering with nearest neighbor linkage is used to visualize any annual biases existing in the measurements. The diurnal distributions for wind speed and direction are additionally estimated and visualized to determine any periods of time which are inconsistent with the typical diurnal cycle for a given monitor. The robust consistency checking method is applied to a set of 44 monitors operating in the San Joaquin Valley (SJV) of Central California over a 9-year period. Monitors from the SLAMS, CIMIS, and RAWS networks are considered. Similar inconsistencies are detected in all three networks; however, network-specific types of inconsistencies are found as well. Copyright © 2008 John Wiley & Sons, Ltd. [source] Big Gun Monitors: Design, Construction and Operations 1914,1945INTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 2 2009ANDREW LAMBERT No abstract is available for this article. [source] A deadlock prevention approach for a class of timed Petri nets using elementary siphons,ASIAN JOURNAL OF CONTROL, Issue 3 2010Jinwei Guo Abstract To solve the problem of deadlock prevention for timed Petri nets, an effective deadlock prevention policy based on elementary siphons is proposed in this paper. Without enumerating reachable markings, deadlock prevention is achieved by adding monitors for elementary siphons, increasing control depth variables when necessary, and removing implicit, liveness-restricted and redundant control places. The final supervisor is live. First, a timed Petri net is stretched into a stretched Petri net (SPN). Unchanging the system performance, each transition in the SPN has a unit delay time. Then the siphon-control-based approach is applied. Monitors computed according to the marking constraints are added to the SPN model to ensure all strict minimal siphons in the net invariant-controlled. A liveness-enforcing supervisor with simple structure can be obtained by reverting the SPN into a TdPN. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society [source] Managers as Monitors: An Analysis of the Non-executive Role of Senior Executives in UK CompaniesBRITISH JOURNAL OF MANAGEMENT, Issue 1 2000Noel O'Sullivan An important aspect of current governance practice is the use of non-executive directors to monitor the behaviour of company management. This paper examines the extent to which senior executives are utilized as non-executives in large UK companies. The results suggest that executive directors are not an important source of non-executive directors. The average number of non-executive directorships held by each executive is 0.22. Indeed, 85% of executives hold no additional directorships. The holding of non-executive directorships is positively related to the strength of board monitoring in the executive's company, executive tenure and company size. Executives in companies with greater growth opportunities and operating in regulated industries are less likely to hold non-executive directorships. [source] HYBRID ACE: COMBINING SEARCH DIRECTIONS FOR HEURISTIC PLANNINGCOMPUTATIONAL INTELLIGENCE, Issue 3 2005Dimitris Vrakas One of the most promising trends in Domain-Independent AI Planning, nowadays, is state-space heuristic planning. The planners of this category construct general but efficient heuristic functions, which are used as a guide to traverse the state space either in a forward or in a backward direction. Although specific problems may favor one or the other direction, there is no clear evidence why any of them should be generally preferred. This paper presents Hybrid-AcE, a domain-independent planning system that combines search in both directions utilizing a complex criterion that monitors the progress of the search, to switch between them. Hybrid AcE embodies two powerful domain-independent heuristic functions extending one of the AcE planning systems. Moreover, the system is equipped with a fact-ordering technique and two methods for problem simplification that limit the search space and guide the algorithm to the most promising states. The bi-directional system has been tested on a variety of problems adopted from the AIPS planning competitions with quite promising results. [source] Scene-Graph-As-Bus: Collaboration between Heterogeneous Stand-alone 3-D Graphical ApplicationsCOMPUTER GRAPHICS FORUM, Issue 3 2000Bob Zeleznik We describe the Scene-Graph-As-Bus technique (SGAB), the first step in a staircase of solutions for sharing software components for virtual environments. The goals of SGAB are to allow, with minimal effort, independently-designed applications to share component functionality; and for multiple users to share applications designed for single users. This paper reports on the SGAB design for transparently conjoining different applications by unifying the state information contained in their scene graphs. SGAB monitors and maps changes in the local scene graph of one application to a neutral scene graph representation (NSG), distributes the NSG changes over the network to remote peer applications, and then maps the NSG changes to the local scene graph of the remote application. The fundamental contribution of SGAB is that both the local and remote applications can be completely unaware of each other; that is, both applications can interoperate without code or binary modification despite each having no knowledge of networking or interoperability. [source] A 3-D Graphical Database System for Landfill Operations Using GPSCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 5 2002H. Ping Tserng Landfill space is an important commodity for landfill companies. It is desirable to develop an efficient tool to assist space management and monitor space consumption. When recyclable wastes or particular waste materials need to be retrieved from the landfill site, the excavation operations become more difficult without an efficient tool to provide waste information (i.e., location and type). In this paper, a methodology and several algorithms are proposed to develop a 3-D graphical database system (GDS) for landfill operations. A 3-D GDS not only monitors the space consumption of a landfill site, but can also provide exact locations and types of compacted waste that would later benefit the landfill excavation operations or recycling programs after the waste is covered. [source] Checkpointing BSP parallel applications on the InteGrade Grid middlewareCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 6 2006Raphael Y. de Camargo Abstract InteGrade is a Grid middleware infrastructure that enables the use of idle computing power from user workstations. One of its goals is to support the execution of long-running parallel applications that present a considerable amount of communication among application nodes. However, in an environment composed of shared user workstations spread across many different LANs, machines may fail, become inaccessible, or may switch from idle to busy very rapidly, compromising the execution of the parallel application in some of its nodes. Thus, to provide some mechanism for fault tolerance becomes a major requirement for such a system. In this paper, we describe the support for checkpoint-based rollback recovery of Bulk Synchronous Parallel applications running over the InteGrade middleware. This mechanism consists of periodically saving application state to permit the application to restart its execution from an intermediate execution point in case of failure. A precompiler automatically instruments the source code of a C/C++ application, adding code for saving and recovering application state. A failure detector monitors the application execution. In case of failure, the application is restarted from the last saved global checkpoint. Copyright © 2005 John Wiley & Sons, Ltd. [source] Fluorescence lifetime imaging of activatable target specific molecular probesCONTRAST MEDIA & MOLECULAR IMAGING, Issue 1 2010Raphael Alford Abstract In vivo optical imaging using fluorescently labeled self-quenched monoclonal antibodies, activated through binding and internalization within target cells, results in excellent target-to-background ratios. We hypothesized that these molecular probes could be utilized to accurately report on cellular internalization with fluorescence lifetime imaging (FLI). Two imaging probes were synthesized, consisting of the antibody trastuzumab (targeting HER2/neu) conjugated to Alexa Fluor750 in ratios of either 1:8 or 1:1. Fluorescence intensity and lifetime of each conjugate were initially determined at endosomal pHs. Since the 1:8 conjugate is self-quenched, the fluorescence lifetime of each probe was also determined after exposure to the known dequencher SDS. In vitro imaging experiments were performed using 3T3/HER2+ and BALB/3T3 (HER2,) cell lines. Changes in fluorescence lifetime correlated with temperature- and time-dependent cellular internalization. In vivo imaging studies in mice with dual flank tumors [3T3/HER2+ and BALB/3T3 (HER2,)] detected a minimal difference in FLI. In conclusion, fluorescence lifetime imaging monitors the internalization of target-specific activatable antibody,fluorophore conjugates in vitro. Challenges remain in adapting this methodology to in vivo imaging. Copyright © 2010 John Wiley & Sons, Ltd. [source] An electro-optic monitor of the behavior of Chlamydomonas reinhardtii ciliaCYTOSKELETON, Issue 2 2005Keith Josef Abstract The unicellular green alga Chlamydomonas reinhardtii steers through water with a pair of cilia (eukaryotic flagella). Long-term observation of the beating of its cilia with controlled stimulation is improving our understanding of how a cell responds to sensory inputs. Here we describe how to record ciliary motion continuously for long periods. We also report experiments on the network of intracellular signaling that connects the environment inputs with response outputs. Local spatial changes in ciliary response on the time scale of the underlying biochemical dynamics are observed. Near-infrared light monitors the cells held by a micropipette. This condition is tolerated well for hours, not interfering with ciliary beating or sensory transduction. A computer integrates the light stimulation of the eye of Chlamydomonas with the ciliary motion making possible long-term correlations. Measures of ciliary responses include the beating frequency, stroke velocity, and stroke duration of each cilium, and the relative phase of the cis and trans cilia. The stationarity and dependence of the system on light intensity was investigated. About 150,000,000 total beat cycles and up to 8 h on one cell have been recorded. Each beat cycle is resolved so that each asynchronous beat is detected. Responses extend only a few hundred milliseconds, but there is a persistence of momentary changes that last much longer. Interestingly, we see a response that is linear with absolute light intensity as well as different kinds of response that are clearly nonlinear, implying two signaling pathways from the cell body to the cilia. Cell Motil. Cytoskeleton 61:83,96, 2005. © 2005 Wiley-Liss, Inc. [source] Continuous glucose monitoring and closed-loop systemsDIABETIC MEDICINE, Issue 1 2006R. Hovorka Abstract Background The last two decades have witnessed unprecedented technological progress in the development of continuous glucose sensors, resulting in the first generation of commercial glucose monitors. This has fuelled the development of prototypes of a closed-loop system based on the combination of a continuous monitor, a control algorithm, and an insulin pump. Method A review of electromechanical closed-loop approaches is presented. This is followed by a review of existing prototypes and associated glucose sensors. A literature review was undertaken from 1960 to 2004. Results Two main approaches exist. The extracorporeal s.c.,s.c. approach employs subcutaneous glucose monitoring and subcutaneous insulin delivery. The implantable i.v.,i.p. approach adopts intravenous sampling and intraperitoneal insulin delivery. Feasibility of both solutions has been demonstrated in small-scale laboratory studies using either the classical proportional,integral,derivative controller or a model predictive controller. Performance in the home setting has yet to be demonstrated. Conclusions The glucose monitor remains the main limiting factor in the development of a commercially viable closed-loop system, as presently available monitors fail to demonstrate satisfactory characteristics in terms of reliability and/or accuracy. Regulatory issues are the second limiting factor. Closed-loop systems are likely to be used first by health-care professionals in controlled environments such as intensive care units. [source] Characterizing blood pressure control in individuals with Type 2 diabetes: the relationship between clinic and self-monitored blood pressureDIABETIC MEDICINE, Issue 9 2003R. S. Mazze Abstract Aims To determine the relationship between blood pressure (BP) measurement in the clinic and self-monitored blood pressure (SMBP); and to evaluate the accuracy of self-reported data in patients with Type 2 diabetes treated intensively for hypertension. Methods Seventy subjects had baseline and 1-week follow-up clinic BP measured using an Omron 907® automated device. During a contemporaneous 14-day period these subjects measured their BP at least four times each day using an Omron IC® semiautomatic portable monitor which, unknown to them, contained an onboard memory capable of storing BP with corresponding time and date. Results There was no significant difference between mean clinic and mean self-monitored BP. Correlations between clinic BP and SMBP were r = 0.61 (P < 0.0001) for systolic BP and r = 0.69 (P < 0.0001) for diastolic BP. Clinic BP classified 56 subjects as uncontrolled hypertension (BP , 130/80 mmHg, adjusted for diabetes) and 14 subjects as controlled hypertension. Using World Health Organization-International Society of Hypertension criteria for SMBP (, 125/75 mmHg), 55 cases of clinic classified uncontrolled hypertension were confirmed, resulting in 98% sensitivity. Clinic and SMBP agreed in one case of controlled hypertension, resulting in 7% specificity. For all subjects, the median percent of values exceeding SMBP criteria for controlled hypertension was systolic 92% and diastolic 70%. Self-reporting precision averaged 89 ± 10% (range 45,100%); under-reporting was 25 ± 16% (ranging from 0 to 56%) and over-reporting was 12 ± 15% (ranging from 0 to 46%). The overall logbook mean was not significantly different from the downloaded data from the Omron IC® monitors. Conclusions SMBP was able to identify 13 patients with uncontrolled hypertension who, by clinic BP measurement, had been classified as controlled. [source] Telemetry Monitoring during Transport of Low-risk Chest Pain Patients from the Emergency Department: Is It Necessary?ACADEMIC EMERGENCY MEDICINE, Issue 10 2005Adam J. Singer MD Abstract Background: Low-risk emergency department (ED) patients with chest pain (CP) are often transported by nurses to monitored beds on telemetry monitoring, diverting valuable resources from the ED and delaying transport. Objectives: To test the hypothesis that transporting low-risk CP patients off telemetry monitoring is safe. Methods: This was a secondary analysis of a prospective, observational cohort of ED patients with low-risk chest pain (no active chest pain, normal or nondiagnostic electrocardiogram, normal initial troponin I) admitted to a non,intensive care unit monitored bed who were transported off telemetry monitor by nonclinical personnel. A protocol allowing transportation of low-risk CP patients off telemetry monitoring to a monitored bed was developed, and an ongoing daily log of patients transported off telemetry was maintained for the occurrence of any adverse events en route to the floor. Adverse events requiring treatment included dysrhythmias, hypotension, syncope, and cardiac arrest. The study population included patients who presented during September,October 2004, whose data were abstracted from the medical records using standardized methodology. A subset of 10% of the medical records were reviewed by a second investigator for interrater reliability. Death, syncope, resuscitation, and dysrhythmias during transport or immediately on arrival to the floor were the outcomes measured. Descriptive statistics and confidence intervals (CIs) were used in data analysis. Results: During the study period, 425 patients had CP of potentially ischemic origin, of whom 322 (75.8%) were low risk and met the inclusion criteria and were transported off monitors. Their mean (±standard deviation) age was 58.3 (±16.0) years; 48.1% were female. During transport from the ED, there was no patient with any adverse events requiring treatment and there was no death (95% CI = 0% to 0.93%). Conclusions: Transportation of low-risk ED chest pain patients off telemetry monitoring by nonclinical personnel to the floor appears safe. This may reduce diversion of ED nurses from the ED, helping to alleviate nursing shortages. [source] Collusion and Organization DesignECONOMICA, Issue 285 2005Kouroche Vafaï This paper investigates how the possibility of collusion between members of an organization affects the choice of organizational design. We consider a moral hazard environment in which a principal chooses the organizational structure before designing contracts. The principal has the choice between a principal,agent organization, where it monitors the output produced by the agent itself, and a principal,supervisor,agent hierarchy, where monitoring is delegated. We identify the conditions under which the possibility of collusion in a principal,supervisor,agent hierarchy entails the superiority of a principal,agent organization. The results suggest that the possibility of collusion may set a limit to the size of organizations. [source] Wading birds as bioindicators of mercury contamination in Florida, USA: Annual and geographic variationENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2002Peter C. Frederick Abstract Mercury contamination in wetland biota is often dynamic, difficult to predict, and costly to track. In this paper, we present results from a six-year study of growing feathers of piscivorous birds as monitors of wetland Hg exposure in Florida, USA, wetlands. Between 1994 and 2000, we collected feathers of growing great egret (Ardea alba) nestlings from colonies in the freshwater Everglades of southern Florida, and during 1998, feathers were collected from chicks of both great egrets and white ibises (Eudocimus albus) at a variety of colonies throughout peninsular Florida. Coastal colonies showed significantly lower feather Hg concentrations than did inland sites. Within the Everglades, we found significant effects of both geographic location and year on age-adjusted mean total Hg concentrations in feathers. Over the course of our study, Everglades colonies maintained their Hg concentration rankings relative to one another, but all showed strongly declining Hg concentrations (mean of 73% averaged across colonies, between 1994 and 2000). Using a previously established predictive relationship between Hg consumption in food and feather Hg for great egrets, we estimated that Hg concentrations in the aggregate diet of egrets have been reduced by an average of 67%. We conclude that the Everglades has undergone a biologically significant decline in Hg availability in the wetland food web, possibly because of decreased local inputs. [source] Predicting intra-urban variation in air pollution concentrations with complex spatio-temporal dependencies,ENVIRONMETRICS, Issue 6 2010Adam A. Szpiro Abstract We describe a methodology for assigning individual estimates of long-term average air pollution concentrations that accounts for a complex spatio-temporal correlation structure and can accommodate spatio-temporally misaligned observations. This methodology has been developed as part of the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air), a prospective cohort study funded by the US EPA to investigate the relationship between chronic exposure to air pollution and cardiovascular disease. Our hierarchical model decomposes the space--time field into a "mean" that includes dependence on covariates and spatially varying seasonal and long-term trends and a "residual" that accounts for spatially correlated deviations from the mean model. The model accommodates complex spatio-temporal patterns by characterizing the temporal trend at each location as a linear combination of empirically derived temporal basis functions, and embedding the spatial fields of coefficients for the basis functions in separate linear regression models with spatially correlated residuals (universal kriging). This approach allows us to implement a scalable single-stage estimation procedure that easily accommodates a significant number of missing observations at some monitoring locations. We apply the model to predict long-term average concentrations of oxides of nitrogen (NOx) from 2005 to 2007 in the Los Angeles area, based on data from 18 EPA Air Quality System regulatory monitors. The cross-validated IR2 is 0.67. The MESA Air study is also collecting additional concentration data as part of a supplementary monitoring campaign. We describe the sampling plan and demonstrate in a simulation study that the additional data will contribute to improved predictions of long-term average concentrations. Copyright © 2009 John Wiley & Sons, Ltd. [source] Bispectral Electroencephalographic Analysis of Patients Undergoing Procedural Sedation in the Emergency DepartmentACADEMIC EMERGENCY MEDICINE, Issue 6 2003James R. Miner MD Abstract Objective: To determine whether there is a correlation between the level of sedation achieved during procedural sedation (PS) in the emergency department as determined by bispectral electroencephalographic (EEG) analysis (BIS) and the rate of respiratory depression (RD), the patient's perception of pain, recall of the procedure, and satisfaction. Methods: This was a prospective observational study conducted in an urban county hospital of adult patients undergoing PS using propofol, methohexital, etomidate, and the combination of fentanyl and midazolam. Consenting patients were monitored by vital signs, pulse oximetry, nasal-sample end-tidal carbon dioxide (ETCO2), and BIS monitors during PS. Respiratory depression (RD) was defined as an oxygen saturation <90%, a change from baseline ETCO2 of >10 mm Hg, or an absent ETCO2 waveform at any time during the procedure. After the procedure, patients were asked to complete three 100-mm visual analog scales (VASs) concerning their perception of pain, recall of the procedure, and satisfaction with the procedure. Patients were divided into four groups based on the lowest BIS score recorded during the procedure, group 1, >85; group 2, 70,85; group 3, 60,69; group 4, <60. Rates of RD and VAS outcomes were compared between groups using chi-square statistics. Results: One hundred eight patients were enrolled in the study. No serious adverse events were noted. RD was seen in three of 14 (21.4%) of the patients in group 1, seven of 34 (20.6%) in group 2, 16 of 26 (61.5%) in group 3, and 18 of 34 (52.9%) in group 4. The rate of RD in patients in group 2 was not significantly different from that in group 1 (p = 0.46). The rate of RD in group 2 was significantly lower than that in groups 3 (p = 0.0003) and 4 (p = 0.006). For the VAS data, when group 1 was compared with the combined groups 2, 3, and 4, it had significantly higher rates of pain (p = 0.003) and recall (p = 0.001), and a dissatisfaction rate (p = 0.085) that approached significance. When groups 2, 3, and 4 were compared with chi-square test, there was not a significant difference in pain (p = 0.151), recall (p = 0.27), or satisfaction (p = 0.25). Conclusions: Patients with a lowest recorded BIS score between 70 and 85 had the same VAS outcomes as more deeply sedated patients and the same rate of RD as less deeply sedated patients. This range of scores represented the optimally sedated patients in this study. [source] Effect of drug-induced cytotoxicity on glucose uptake in Hodgkin's lymphoma cellsEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 2 2006Ursula Banning Abstract:,Background:,In Hodgkin's lymphoma, F-18-fluoro-deoxy- d -glucose positron emission tomography (FDG-PET) is used for staging and response evaluation after chemotherapy. However, drug-mediated downregulation of glucose uptake in viable Hodgkin's lymphoma cells might limit the use of FDG-PET. Methods:,We analyzed the effect of etoposide on cell viability and uptake of F-18-fluoro-deoxy- d -glucose or the glucose analog 2-[N -(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxyglucose (2-NBDG) in vitro. Results:,Etoposide induced a dose-dependent cytotoxicity in HDLM-2 cells which was significantly correlated with reduced FDG uptake. However, it also significantly increased the portion of viable cells which did not take up 2-NBDG. Interestingly, etoposide-induced cytotoxicity was mainly mediated via caspase-dependent mechanisms, whereas the cell death induced by deprivation of glucose was mediated via caspase-independent mechanisms. Conclusion:,Etoposide-mediated reduction of glucose uptake by Hodgkin's lymphoma cells is mainly caused by cell death. In a small fraction of viable cells, etoposide might downregulate glucose transporters and/or hexokinase activity and by that inhibit glucose uptake. This, however, might not lead to false-negative results of response evaluation in Hodgkin's lymphoma patients after chemotherapy, because inhibition of glucose uptake itself seems to be a strong inducer of cell death. Altogether, this study provides important in vitro evidence to clarify the mechanisms by which FDG-PET monitors the effect of anti-cancer treatment in Hodgkin's lymphoma patients. [source] Continuous Electrocardiographic Monitoring and Cardiac Arrest Outcomes in 8,932 Telemetry Ward PatientsACADEMIC EMERGENCY MEDICINE, Issue 6 2000Michael J. Schull MD Abstract. Objective: To estimate the benefit of routine electrocardiographic (ECG) telemetry monitoring on in-hospital cardiac arrest survival. Methods: In a tertiary care hospital, all telemetry ward admissions and cardiac arrests occurring over a five-year period were reviewed. Ward location and survival to discharge were determined for all patients outside of critical care areas. Results: During the study period, 8,932 patients were admitted to the telemetry ward, and 20 suffered cardiac arrest (0.2%; 95% CI = 0.1 to 0.3). Telemetry monitors signaled the onset of cardiac arrest in only 56% (95% CI = 30 to 80) of monitored arrests. Three patients survived to discharge, and in two of these three patients the arrest onset was signaled by the monitor. This yields a monitor-signaled survival rate among telemetry ward patients of 0.02% (95% CI = 0 to 0.05). All survivors suffered significant arrhythmias prior to their cardiac arrests. Conclusions: Cardiac arrest is an uncommon event among telemetry ward patients, and monitor-signaled survivors are extremely rare. Routine telemetry offers little cardiac arrest survival benefit to most monitored patients, and a more selective policy for telemetry use might safely avoid ECG monitoring for many patients. [source] Increase of calnexin gene dosage boosts the secretion of heterologous proteins by Hansenula polymorphaFEMS YEAST RESEARCH, Issue 7 2007Jens Klabunde Abstract The type I membrane protein calnexin is a conserved key component of the quality control mechanism in the endoplasmic reticulum. It functions as a molecular chaperone that monitors the folding state of nascent polypeptides entering the endoplasmic reticulum. Calnexin also behaves as a lectin, as its chaperoning activity involves binding of oligosaccharide moieties present on newly imported glycoproteins. We isolated the calnexin gene (HpCNE1) from the methylotrophic yeast Hansenula polymorpha, and used HpCNE1 expression plasmids for supertransformation of H. polymorpha strains secreting target proteins of biotechnological interest. The elevated dosage of HpCNE1 enhanced secretion of the four proteins tested: three glycoproteins and one unglycosylated product. Secretion of bacterial alginate epimerase AlgE1 was increased threefold on average, and secretion of both human interferon-, and fungal consensus phytase twofold. With phytase and AlgE1 this improvement was all the more remarkable, as the secretion level was already high in the original strains (g L,1 range). The same approach improved secretion of human serum albumin, which lacks N-linked glycans, about twofold. Glycosylation of the pro-MF,1 leader may account for the effect of calnexin in this case. Our results argue that cooverexpression of calnexin can serve as a generally applicable tool for enhancing the secretion of all types of heterologous protein by H. polymorpha. [source] The use of transient pressure analysis at the Dounreay Shaft Isolation Project.GEOMECHANICS AND TUNNELLING, Issue 5 2009Die Verwendung der Analyse instationärer Druckentwicklung am Dounreay Schachtabdichtungsprojekt Grouting; Innovative methods; Injektionen; Neue Verfahren Abstract This paper provides an assessment of the use of pressure fall-off data during the Dounreay Shaft Isolation Project. The instrumentation controlling the injection of grout monitors and records both the pressure and the flow rate throughout the process, so pressure fall-off data is collected during any pauses to, and at the end of, each grout injection. The shapes of the pressure fall-off vs time curves have been examined qualitatively and categorised. The fall-off data has also been examined using PanSystem well test software, which creates the pressure change and pressure derivative curves, then attempts to simulate the fall-off curve by iteration after selection of a flow and boundary model chosen from the wide range available. The implications that the shapes of the pressure and derivative curves and the flow and boundary models have for the grout curtain have been examined. The caveats that surround the quantitative use of results from Pan-System analyses for a cement grout rather than a Newtonian fluid are discussed. Diese Veröffentlichung handelt von der Beurteilung des Einsatzes und der Analyse von Daten zum Druckabfall im Zuge der Injektion am Schachtabdichtungsprojekt Dounreay, Schottland, UK. Die Instrumentation der Baustelle war darauf ausgelegt, Messwerte von Druck und Injektionsrate anzuzeigen, aufzuzeichnen und als Diagramm darzustellen. Damit war es möglich, in jeder Injektionsunterbrechung (also bei Rate = Null) und zu jedem Passenende Druckabfalldaten aufzuzeichnen. Die Form dieser Druckabfallkurven gegen die Zeit wurde qualitativ untersucht und kategorisiert. Eine weitere Interpretation dieser Daten erfolgte mittels des Programms "PanSystem". Bei dieser Methodik werden die Druckänderungen über kleine Zeitinkremente errechnet und deren Ableitung über die Zeit in Kurvenform dargestellt. Durch iterative Simulation und Eingabe von Randbedingungen ("boundaries") für das jeweilige Strömungsmodell , ausgewählt aus einer weiten Bandbreite von Möglichkeiten , ergibt sich die Möglichkeit, u. a. die Strömungsdimension, Strömungshindernisse und Reichweite der Injektion zu prognostizieren. Die daraus gezogenen Schlüsse für den Injektionsschirm wurden für die qualitative Abnahme der Arbeiten mitverwendet. In dem vorliegenden Artikel wird auch auf die möglichen Vorbehalte eingegangen, die sich aus den rheologischen Abweichungen von Injektionsmischungen gegenüber einer Newtonschen Flüssigkeit ergeben. [source] Ionic dialysance: Principle and review of its clinical relevance for quantification of hemodialysis efficiencyHEMODIALYSIS INTERNATIONAL, Issue 2 2005Lucile Mercadal Ionic dialysance (D) is an online measured variable now available on several dialysis monitors to evaluate small-solute clearance. Based on conductivity measurements in the inlet and outlet dialysate, the principle of the measurement and the different measurement methods are described. Studies that have evaluated the reliability of ionic dialysance to assess dialysis efficiency are discussed. These studies are divided into two groups: the first comparing ionic dialysance to urea clearance and the second comparing Dt/V to Kt/Vurea, in which the uncertainties of the measurement of Vurea could have misrepresented the relationship between Dt/V and Kt/Vurea. When Kt/Vurea via the Daugirdas second-generation equation taking the rebound into account is considered, slight,even nonsignificant,differences are evidenced between Kt/Vurea and Dt/V. Therefore, ionic dialysance should be considered as a valid measure in future guidelines for dialysis efficiency. [source] Tandem dialyzers with dual monitors to meet Kt/V targetsHEMODIALYSIS INTERNATIONAL, Issue 1 2005N. Sridhar Objective:,A large body mass and/or a poorly functioning vascular access predispose to inadequate Kt/V. Double dialyzers in parallel and tandem have been shown to enhance Kt/V to levels recommended by K/DOQI. We experienced difficulties with unintended excessive ultrafitration (UF), positive transmembrane pressure (TMP)-triggered pump stoppage, need for large volume saline infusion (inflating Kt/V), and a high incidence of clotting of the second dialyzer in tandem. Since blood and dialysate flow rates are higher in the tandem configuration, Kt/V should be theoretically higher. We developed a technique of using the tandem configuration with two monitors in which all the UF could be limited to the second dialyzer, the TMP of the two dialyzers independently controlled, TMP reversal eliminated, and saline infusion and unintended UF minimized. Methods:,3 large male patients with AV grafts (AVG) and 2 with tunneled catheters (TC) had 7 treatments (with Kt/V and URR calculated using the stop-flow technique in the last 5) sessions of each of single, double parallel, and tandem configurations. Blood (Qb) and dialysate-flow (Qd) were halved with Y-connectors in the parallel configuration. Qb through both dialyzers and Qd through the second were controlled with the first monitor and Qd (TMP set to near zero) through the first dialyzer controlled with the second monitor using recirculating saline through its blood pump (with the "venous" pressure adjusted using an air-filled syringe) in the tandem configuration. The patient's blood did not circulate through the blood-pump of the first machine. Qd was 500 ml/min through each dialyzer in the single and tandem and 250 ml/min in the parallel configurations. Processed blood volume (dialysis time) was exactly 85 L with AVG and 60 L with TC. Heparin dosage was constant. ANOVA, 2 × k tables, and Neuman-Keuls test were used in analyzing data. Results:,Mean Kt/V (%URR) increased from 1.15 (62) with single to 1.35 (68) with parallel (p < 0.02) and 1.48 (71) with tandem (p < 0.001) dialyzers in patients with AVG but not TC [1.05 (58), 1.02 (55), and 1.25 (64) with single, parallel, and tandem, respectively]. Tandem dialyzers met targets for URR (p < 0.001) and Kt/V ( p < 0.05) more frequently than parallel with AVG but not TC. Conclusions:,Tandem dialyzers with 2 monitors are more successful than parallel dialyzers in delivering target Kt/V and URR when Qb is not compromised. [source] Technical note: Usability evaluation of the modified CIE1976 Uniform-Chromaticity scale for assessing image quality of visual display monitorsHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 1 2003WookGee Lee White uniformity indicates the degree of uniform distribution of white color across the display screen and is one of the important inspection factors determining the image quality of a visual display unit (VDU). Experiments in which participants were confronted with 6 evaluation points embedded in 3 measurement groups on a VDU screen were conducted to gather the psychophysical data that include the levels of white uniformity obtained from participants and a colorimetric system (CA-100). In an accuracy test, 37.12% of the participants showed the same conclusion led by the original CIE1976 criteria, and 62.88% of the participants showed the same conclusion led by the modified equation. In magnitude estimation evaluating the display's white uniformity, the magnitude score of the modified equation (0.36) was significantly larger than that of the original equation (0.32). It was concluded that the modified equation is more sensitive to the change of white uniformity. © 2003 Wiley Periodicals, Inc. Hum Factors Man 13: 85,95, 2003. [source] Management of diabetes using adaptive controlINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 5 2005Roman Hovorka Abstract The review focuses on adaptive systems for insulin treatment in type 1 diabetes. The review consists of two parts. First, adaptive approaches are described, which exploit infrequent glucose measurements (four to seven measurements per day). Second, adaptive approaches are described, which exploit frequent or continuous glucose measurements (every hour or more often). Each part is further divided into two subparts separating off-line and on-line adaptive techniques. The latter represents treatment strategies, which rely on continuous re-assessment of the glucoregulatory system. The former refers to treatment strategies, which are fixed for a day or longer and are revisited from time to time. It is concluded that the role of adaptive approaches will increase as new continuous glucose-sensing monitors reach the market. Copyright © 2004 John Wiley & Sons, Ltd. [source] An algorithm for evaluating the ethics of a placebo-controlled trialINTERNATIONAL JOURNAL OF CANCER, Issue 5 2001Robert J. Amdur M.D. Abstract The purpose of this article is to clarify the decision points that are important to consider when evaluating the ethics of a placebo-controlled trial. The ethical requirements for research involving human subjects are reviewed, and the rationale for and potential problems with concomitant placebo control are explained. A series of case discussions are used to illustrate each decision point. The critical decision points in the evaluation of the ethics of a placebo-controlled trial are as follows: (i) Is placebo being used in place of standard therapy? (ii) Is standard therapy likely to be effective? (iii) Is the toxicity of standard therapy such that patients routinely refuse this treatment? (iv) Could the use of placebo result in severe suffering or irreversible harm? (v) Is the variability in the placebo response such that it is reasonable to consider other options for the control group? (vi) Would a reasonable person with an average degree of altruism and risk aversiveness agree to participate in this study? The algorithm presented in this article gives researchers and research monitors (such as Institutional Review Board members) the tools they need to evaluate the ethics of a study that uses concomitant placebo control. © 2001 Wiley-Liss, Inc. [source] Strategies to reduce medication errors with reference to older adultsINTERNATIONAL JOURNAL OF EVIDENCE BASED HEALTHCARE, Issue 1 2006Brent Hodgkinson BSc (Hons) MSc GradCertPH GradCertEcon(Health) Abstract Background, In Australia, around 59% of the general population uses prescription medication with this number increasing to about 86% in those aged 65 and over and 83% of the population over 85 using two or more medications simultaneously. A recent report suggests that between 2% and 3% of all hospital admissions in Australia may be medication related with older Australians at higher risk because of higher levels of medicine intake and increased likelihood of being admitted to hospital. The most common medication errors encountered in hospitals in Australia are prescription/medication ordering errors, dispensing, administration and medication recording errors. Contributing factors to these errors have largely not been reported in the hospital environment. In the community, inappropriate drugs, prescribing errors, administration errors, and inappropriate dose errors are most common. Objectives, To present the best available evidence for strategies to prevent or reduce the incidence of medication errors associated with the prescribing, dispensing and administration of medicines in the older persons in the acute, subacute and residential care settings, with specific attention to persons aged 65 years and over. Search strategy, Bibliographic databases PubMed, Embase, Current contents, The Cochrane Library and others were searched from 1986 to present along with existing health technology websites. The reference lists of included studies and reviews were searched for any additional literature. Selection criteria, Systematic reviews, randomised controlled trials and other research methods such as non-randomised controlled trials, longitudinal studies, cohort or case,control studies, or descriptive studies that evaluate strategies to identify and manage medication incidents. Those people who are involved in the prescribing, dispensing or administering of medication to the older persons (aged 65 years and older) in the acute, subacute or residential care settings were included. Where these studies were limited, evidence available on the general patient population was used. Data collection and analysis, Study design and quality were tabulated and relative risks, odds ratios, mean differences and associated 95% confidence intervals were calculated from individual comparative studies containing count data where possible. All other data were presented in a narrative summary. Results, Strategies that have some evidence for reducing medication incidents are: ,,computerised physician ordering entry systems combined with clinical decision support systems; ,,individual medication supply systems when compared with other dispensing systems such as ward stock approaches; ,,use of clinical pharmacists in the inpatient setting; ,,checking of medication orders by two nurses before dispensing medication; ,,a Medication Administration Review and Safety committee; and ,,providing bedside glucose monitors and educating nurses on importance of timely insulin administration. In general, the evidence for the effectiveness of intervention strategies to reduce the incidence of medication errors is weak and high-quality controlled trials are needed in all areas of medication prescription and delivery. [source] Vision system for on-line characterization of paper slurry ,INTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 4 2000Hamed Sari-Sarraf This paper presents a detailed description of a vision system that detects and localizes the nonuniformities that appear on the paper slurry (wood fiber and water mixture) at the wet end of a paper machine. Specifically, the system monitors the paper slurry as it exits the headbox and alerts the operators of any event (e.g., streaks) that disrupts the otherwise homogeneous background. These events affect crucial product properties such as formation. A poor formation results in thick and thin spots on the sheet and impacts its strength and printability. This paper describes the vision system in terms of its hardware modules, as well as the image processing algorithms that it utilizes to perform its function. The system acquires intensity and topographic information from the scene. It uses texture-based features for the detection and facet-based descriptors for the localization of the nonuniformities. In addition to being tested in a laboratory environment, a prototype of this system was constructed and deployed to a paper mill, where its performance was evaluated under realistic conditions. Installed on a fourdrinier paper machine, running at 480 m/min and producing linerboard material, the vision system monitored about a 1 m wide area and successfully detected and localized slurry streaks. Published 2001 John Wiley & Sons, Inc. Int J Imaging Syst Technol, 11, 231,242, 2000 [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||