Search

BACKGROUND: A percutaneous transthoracic needle biopsy (PTNB) is performed to obtain tissue for a pathologic diagnosis. A PTNB is necessary prior to the initiation of many cancer treatments. There is a risk of hemoptysis, the expectoration of blood, with the possibility for adverse, life-threatening outcomes. A critical event checklist is a cognitive aid used in an emergency to ensure critical steps are followed. To date, there are no known checklists published for management of PTNB-related, life-threatening hemoptysis. The purpose of this report is to describe the development and implementation of a critical event checklist and the adoption of the checklist into hemoptysis management. METHODS: In March 2017, a process improvement team convened to evaluate the hemoptysis response using the Plan-Do-Study-Act (PDSA) methodology. The checklist was evaluated and updated through September 2019. The team educated Interventional Radiology (IR) clinicians on the new checklist and conducted simulations on its use. A retrospective chart review was performed on hemoptysis events between the ten-year period of October 1, 2008 and September 30, 2018 to evaluate the adoption of the checklist into practice. RESULTS: There were 231 hemoptysis events occurring in 229 patients (2 with repeat biopsies). Prior to implementing the protocol and checklist, there were 166 (71.9%) hemoptysis events. After implementation there were 65 (28.1%) events. The median amount of documented blood expectorated with hemoptysis was 100 mL (IQR 20.0–300.0). Twenty-six patients were admitted after PTNB for reasons related to the hemoptysis event (11.3%). During the procedure, four (1.7%) patients with hemoptysis suffered a cardiac arrest. Prior to implementation of the protocol and critical events checklist, nurses positioned patients in the lateral decubitus (LD) position in 40 out of 162 (24.7%) cases. After implementation of the critical events checklist, nurses positioned patients in the LD position 42 out of 65 cases (64.6%) (OR=5.57(95% CI 2.99–10.367), p

Quantitative risk assessment (QRA) techniques methodically assess the likelihood, impact, and subsequently the risk of adverse events. In a typical QRA method, one of the main intentions is to identify the critical root events which mostly contribute to the risk of the top event (TE) and requiring subsequent corrective actions (CAs). Finding the critical events which contribute to the risk is significantly dependent on the assumptions and methods applied to integrate the probabilities of different events and these events may have really low probability of occurrence. Thus, the probability reduction of the critical root events and subsequently the system’s failure does not lead to an optimal solution. For this reason, ranking the CAs without consideration of several aspects such as their influence on root events probability, inter-relationships, and direct/indirect cost, is not an appropriate approach. This study aims to introduce an approach to deal with the aforementioned situations. A novel extension to DEMATEL (decision making trial and evaluation laboratory) named Pythagorean fuzzy DEMATEL is proposed on a common probabilistic safety analysis. As a case study, a collapse in an offshore facility platform (including 42 basic events and corresponding 30 CAs) is considered to illustrate the effectiveness of the presented approach. The application of the model confirms its robustness in prioritizing critical root events and CAs compared with a conventional model, consideration of the influencing factors, and a dynamic and flexible structure.

Driver distraction is one major cause of road traffic accidents. In order to avoid distraction-related accidents it is important to inhibit irrelevant stimuli and unnecessary responses to distractors and to focus on the driving task, especially when unpredictable critical events occur. Since inhibition is a cognitive function that develops until young adulthood and decreases with increasing age, young and older drivers should be more susceptible to distraction than middle-aged drivers. Using a driving simulation, the present study investigated effects of acoustic and visual distracting stimuli on responses to critical events (flashing up brake lights of a car ahead) in young, middle-aged, and older drivers. The task difficulty was varied in three conditions, in which distractors could either be ignored (perception-only), or required a simple response (detection) or a complex Go-/NoGo-response (discrimination). Response times and error rates to the critical event increased when a simultaneous reaction to the distractor was required. This distraction effect was most pronounced in the discrimination condition, in which the participants had to respond to some of the distracting stimuli and to inhibit responses to some other stimuli. Visual distractors had a stronger impact than acoustic ones. While middle-aged drivers managed distractor inhibition even in difficult tasks quite well (i.e., when responses to distracting stimuli had to be suppressed), response times of young and old drivers increased significantly, especially when distractor stimuli had to be ignored. The results demonstrate the high impact of distraction on driving performance in critical traffic situations and indicate a driving-related inhibition deficit in young and old drivers.

Fire is the foremost critical event for road tunnels' safety. Therefore, the European Commission introduced the Directive 2004/54/EC for enhancing tunnels' safety since they constitute a key element of the Trans-European Road Network. The Directive has established a common ground for tunnels' safety evaluation providing certain minimum requirements while introducing officially the use of risk assessment. Despite the significant progress, this paper illustrates that further efforts are needed. Through a comparative review of the risk assessment methods, questions about the level of harmonisation of the framework are raised. Moreover, considerable problems are highlighted, like the incorporation of the new trends emerging from the literature or the deficiencies on addressing significant issues of the analysis, such as the risk acceptance criteria and the behaviour of trapped-users. These problems can affect the risk assessment process causing both significant discrepancies and deficiencies at the estimated level of tunnels' safety. Uncovering, thus, the deficiencies and limitations of the methods, this paper contributes to i) the discourse for initiating relevant studies to enhance tunnels’ fire safety in Europe and worldwide, and ii) the harmonisation of risk assessment methods. Keywords: Road tunnel, Safety, Fire, Risk assessment

The ways through which we define fetuses and pregnant women has consequences in matters of abortion rights, in care following pregnancy loss and in the emotional experience of loss itself. Considering that maternal-fetal body, fetus status and maternal subjectivity are ontologically ambiguous, socially and technologically constructed and that they endure political tensions, this autoethnographic reflection on my cervical ectopic pregnancy focuses on how diverse medical-technological devices formed a semiotic and material field that modified my subjectivity making and unmaking a mother and transformed the status of personhood of my embryo from a quasi-child into a sort of cancer. By differentiating maternal status from maternal subjectivity, I also show how in western societies the maternal status of pregnant women is strictly linked to a pregnant body and to an existing and living fetus or embryo, but in the critical event of pregnancy loss, maternal subjectivity can follow other paths, paths that lack social recognition.

Because current automated vehicles have operational limitations, it is important to ensure that the fallback-ready driver is able to perform appropriately when required to take over control of the vehicle. However, time-related increase in driver drowsiness is well-known, and drowsy driving can affect response to take-over request (TOR). It was previously reported that a scheduled period of manual driving during automated driving was beneficial in maintaining driver arousal level. The present driving simulator study investigates the effects of scheduled manual driving on driver drowsiness and performance, as well as age differences therein. A total of 115 participants, whose gender was balanced and age was distributed uniformly from 20 to 70 years, drove an automated vehicle for 31 min, and a TOR was prompted before a collision event. A between-subjects design comprised two conditions: with versus without a scheduled 10-min interval of manual driving that ended 10 min before TOR. The Karolinska Sleepiness Scale and eyeblink durations estimated from electrooculograms (EOG) were used to subjectively and objectively measure participant’s drowsiness. Reaction time, standard deviation of steering wheel angle, and minimum Time-to-Collison (TTC) were extracted to measure driver performance in response to TOR. The alleviating effect on drowsiness of 10-min scheduled manual driving became non-significant after another 10-min period of automated driving. Although the scheduled manual driving had no significant effect for younger drivers, older drivers reacted significantly more slowly in both steering and braking at the critical event. These findings provide essential insights for human-vehicle interactions: Scheduled manual driving cannot maintain drivers’ arousal level for 10 min afterwards, and for older drivers, it would be better to avoid unnecessary task-switching between manual and automated driving.

Soil moisture is a key state variable in terrestrial water cycles, which links various land surface and hydrological processes. Owing to the significant spatiotemporal variability in soil moisture, collecting sufficient soil moisture data for relevant studies can be an astonishingly difficult task. Here, a statistical method based on the concept of depth functions was used to define Critical Events (CE) of soil moisture, which was hypothesized to contain disproportionally more system information on soil moisture dynamics. To test the feasibility of applying the CE concept for quantifying soil moisture dynamics, a long-term soil moisture dataset was retrieved from the Automated Weather Data Network (AWDN) located in the continental United States. The method of Temporal Stability Analysis (TSA) was adopted to examine the information embedded in soil moisture data that were collected under different conditions. The results showed that similar information on the relative as well as absolute wetness conditions at the AWDN sites was extracted from the entire time series and CEs of soil moisture, the latter of which contained much less soil moisture observations. Finally, the field data revealed that the occurrence of CEs of soil moisture in the study area was mainly affected by soil depth and interannual variability in precipitation. The number of CEs of soil moisture tended to be larger at deeper soil depths as well as in either dry or wet years than in normal years, suggesting that more soil moisture measurements under those conditions were needed to provide adequate information on soil moisture systems.

Stent infection after drug-eluting stent implantation is uncommon but is a critical event. In this study, we describe two such cases of coronary stent infection but with varied presentation. The first patient presented with recurrent stent thrombosis and acute coronary syndrome while the second patient was erroneously diagnosed as having tubercular pericarditis and was started on anti-tubercular therapy. Due to their possible fatal outcome, we herein report our experience with this uncommon clinical entity to help in rapid diagnosis and treatment. .

This paper presents a new decision-gathering scheme that aims at detecting a critical event in an Area of Interests (AoI), where a wireless sensor network is deployed in a group of clusters. The proposed scheme assigns a single time slot for each cluster, where all cluster members simultaneously report their binary decisions to the cluster head on that time slot. As the cluster head is interested in the sum of the binary decisions (not the exact binary decisions), the performance loss due to the concurrent transmission is insignificant compared to the co-channel interference induced from other clusters based on conventional schemes. The main advantage of the proposed scheme is that it avoids the co-channel interference between different clusters and assures minimal delay in detecting the critical event, which is very crucial in many security related applications and scenarios. Both simulation and mathematical analysis of the overall decision-error probability of the proposed scheme are carried out, which demonstrate the effectiveness of the proposed scheme.

This eight-year longitudinal study explores the roles writing played in the disciplinary “becoming” (Stevens et al., 2008) of Fabiola, a Spanish-English bilingual who began her schooling in English (and the US) in ninth grade and went on to complete a Gender and Women's Studies (GWS) major at a U.S. university. I use a longitudinal interactional histories approach (Kibler, 2013) to examine selected writing events preceding the “critical event” (Webster & Mertova, 2007) of her choice to major in GWS, demonstrating how she engaged in writing tasks that supported her burgeoning interest in feminism even when not yet part of GWS communities. I then turn to two key writing events after Fabiola chose this major that exemplify how she forged unique yet circumscribed disciplinary identities through writing: first, through an essay on queerness and religion, for which she balanced disciplinary and nonacademic audiences, and second through a series of blog posts in which she presented multiple identities (including contested ones) as key to her disciplinary interactions. The article closes with a discussion of relationships among writing, instruction, and disciplinary becoming, as well as an analysis of ways in which Fabiola's biliterate and L2 writer identities were marginalized in this process.

Diabetic retinopathy is an ocular complication associated with the chronic endocrine disorder of diabetes mellitus. Angiogenesis is adjudged as a prime modulatory event in this complication. The formation of new blood vessels on the pre-existing vasculature gives rise to an abundance of anatomical and physiological alterations which ultimately results in vision loss. The drastic consequences of this complication prompt the obligation of developing effective therapies for its cure. The existing therapy mainly includes destructive techniques such as laser photocoagulation. Owing to the various drawbacks associated with this technique, there is a need to develop alternative therapies which could halt the progression of diabetic retinopathy without causing considerable damage to the retinal cells. One such possible alternative treatment being researched upon is the antiangiogenic therapy. Since angiogenesis is a critical event during the progression of this disorder, targeting this event may perhaps prove effective in its treatment. Amongst several antiangiogenic agents, thalidomide holds a reputable position due to its effectiveness in terminating angiogenesis during various pathological conditions. This review focuses on the diverse molecular mechanisms proposed to explain the antiangiogenic properties of thalidomide and their applicability in diabetic retinopathy.

Simulation is a pedagogical method known to be a generator of stress, that could be influenced by previous stressful experiences.The purpose of this study was to determine the impact of previous experience with a clinical critical event on the stress experienced by nursing students during simulation session of critical events, and on the stress experienced during clinical critical events subsequent to the training.Observational case-control study.Four critical event scenarios were created using full-scale simulation.Two hundred and fifteen undergraduate nursing students of semester four. The control group (n = 112) consisted of learners who had not previously experienced a critical event. The prior exposure group (n = 103) consisted of learners who had experienced a critical event prior to the course.Stress levels were assessed using the self-report stress numerical rating scale-11.There was no significant difference in the level of stress between the prior exposure group and the control group before, during or expected after the simulation session. A significant decrease in stress was observed in both groups from before the course to during the session (p 0.05) and expected after the session (p 0.05). There was no significant difference between the expected post-session stress level and the stress levels reported four months after the training (p = 0.966). At four months, there was no significant difference in stress levels between the groups (p = 0.212).The prior experience of a clinical critical event before a simulation course did not influence their reported stress level during the simulation session. Conversely, simulation-based training of critical situations appears to reduce the level of self-assessed stress during critical events in clinical practice after the training.

Tunnel fire is one of the most severe global fire hazards and causes a significant amount of economic losses and casualties every year. Over the last 50 years, numerous full-scale and reduced-scale tunnel fire tests, as well as numerical simulations have been conducted to quantify the critical fire events and key parameters to guide the fire safety design of the tunnel. In light of the recent advances in big data and artificial intelligence, this paper aims to establish a database that contains all existing experimental data of tunnel fire, based on an extensive literature review on tunnel fire tests. This tunnel-fire database summarizes seven key parameters of flame, ventilation, and smoke in that is open access at a GitHub site: https://github.com/PolyUFire/Tunnel_Fire_Database . The test conditions, experimental phenomena, and data of each literature work were organized and categorized in a standard format that could be conveniently accessed and continuously updated. Based on this database, machine learning is applied to predict the critical ventilation velocity of a tunnel fire as a demonstration. The review of the current database not only reveals more valuable information and hidden problems in the conventional collection of test data, but also provides new directions in future tunnel fire research. The established database and methodology help promote the application of artificial intelligence and smart firefighting in tunnel fire safety.

The distribution of waiting times until the occurrence of a critical event is a crucial statistical problem across several disciplines in Science. In this work we present a statistical model in which a relevant quantity X accumulates until overcoming a threshold X ∗ , which defines the collapse. The obtained waiting time distribution is a mixture of gamma distributions, which in turn can be approximated as an effective gamma distribution.

The understanding of the root causes of traffic collisions has taken a new turn with naturalistic driving studies. Naturalistic driving Data bring insight into normal behavior on the road and help characterize safety related and safety critical events (SCEs) through kinematic triggers and video analysis. The UDRIVE Database includes two million kilometers of naturalistic driving and was recorded in five European countries between 2015 and 2017. Given the large volume of raw data considered, the performance of these kinematic triggers in detecting SCEs should be carefully evaluated to optimize the human resources required to discard false positive events. The aim of the present article is twofold: (i) to describe the triggers used to detect safety critical events from the UDRIVE Database and (ii) to discuss the relevance of SCE triggers performance evaluation used in the literature.

SummaryOne critical event in reprogramming to pluripotency is erasure of the somatic transcriptional program of starting cells. Here, we present the proof of principle of a strategy for reprogramming to pluripotency facilitated by small molecules that interfere with the somatic transcriptional memory. We show that mild chemical targeting of the acetyllysine-binding pockets of the BET bromodomains, the transcriptional bookmarking domains, robustly enhances reprogramming. Furthermore, we show that chemical targeting of the transcriptional bookmarking BET bromodomains downregulates or turns off the expression of somatic genes in both naive and reprogramming fibroblasts. Chemical blocking of the BET bromodomains also results in loss of fibroblast morphology early in reprogramming. We therefore experimentally demonstrate that cell fate conversion can be achieved by chemically targeting the transcriptional bookmarking BET bromodomains responsible for transcriptional memory.

Hospitalized patients outside of the operating room frequently require emergency airway management. This study investigates complications of emergency airway management in critically ill adults, including: (1) the incidence of difficult and failed intubation; (2) the frequency of esophageal intubation; (3) the incidence of pneumothorax and pulmonary aspiration; (4) the hemodynamic consequences of emergent intubation, including death, during and immediately following intubation; and (5) the relationship, if any, between the occurrence of complications and supervision of the intubation by an attending physician.Data were collected on consecutive tracheal intubations carried out by the intensive care unit team over a 10-month period. Non-anesthesia residents were supervised by anesthesia residents, critical care attending physicians, or anesthesia attending physicians.Two hundred ninety-seven consecutive intubations were carried out in 238 adult patients. Translaryngeal tracheal intubation was accomplished in all patients. Intubation was difficult in 8% of cases (requiring more than two attempts at laryngoscopy by a physician skilled in airway management). Esophageal intubation occurred in 25 (8%) of the attempts but all were recognized before any adverse sequelae resulted. New infiltrates suggestive of pulmonary aspiration were present on chest radiography after 4% of intubations. Seven patients (3%) died during or within 30 min of the procedure. Five of the seven patients had systemic hypotension (systolic blood pressureor = 90 mmHg), and four of the five were receiving vasopressors to support systolic blood pressure. Patients with systolic hypotension were more likely to die after intubation than were normotensive patients (P0.001). There was no relationship between supervision by an attending physician and the occurrence of complications.In critically ill patients, emergency tracheal intubation is associated with a significant frequency of major complications. In this study, complications were not increased when intubations were accomplished without the supervision of an attending physician as long as the intubation was carried out or supervised by an individual skilled in airway management. Mortality associated with emergent tracheal intubation is highest in patients who are hemodynamically unstable and receiving vasopressor therapy before intubation.

The development of tourism projects is often predicated on land expropriation. It is therefore important to understand residents' attitudes towards land expropriation and how changes in those attitudes can benefit both the land expropriation process and tourism development. Taking Wudaoliang in Sandaogou village in Hebei province as a case study, this study focuses on residents' attitudinal change by taking a longitudinal approach involving non-participant observation and 180 interviews. Critical event analysis was conducted, and a framework for modelling attitudinal change was adopted. The results show that the attitudes of rural residents towards tourism development were not static but underwent a dynamic process of change across three phases. These results suggest that residents should deepen their involvement in the land expropriation process and that information transparency can reduce social conflict, which will facilitate the sustainable development of rural tourism. The theoretical and practical contributions of this study are also discussed.

Helium Cooled Pebble Bed (HCPB) blanket concept is one of the DEMO (Demonstration Power Plant) blanket concepts running for the final design selection. Concept relevant safety needs to be addressed at the early stage of the design. In this paper the preliminary safety studies for the current concept have been performed with respect to the FFMEA (Functional Failure Mode and Effect Analysis), the confinement strategy, identification of source terms, and selection of critical event sequences. © 2015 Elsevier B.V. All rights reserved.

In 2012, NASA began exploring the feasibility of single pilot/reduced crew operations in the context of scheduled air carrier operations. The current study examined how important it was for ground-based personnel providing support to single piloted aircraft (ground operators) to have opportunities to acquire situation awareness (SA) prior to being called on to assist an aircraft. We looked at two distinct concepts of operation, which varied in how much information was available to ground operators prior to being called on to assist a critical event (no vs. some Situation Preview). Thirty-five commercial pilots participated in the current study. Results suggested that a ground operators’ lack of initial SA when called on for dedicated assistance is not an issue, at least when the ground operator station displays environmental and systems data which are important to gaining overall SA of the specified aircraft. With appropriate displays, ground operators were able to provide immediate assistance, even if they had minimal SA prior to getting a request.

The main goal of the study presented in this paper was to analyse the mechanisms affecting an Underground Coal Gasification (UCG) process and to identify possible deviations of the system from normal work to limit, or even avoid, losses. The UCG process is one of the most innovative technologies connected with the exploitation of coal deposits that are currently being tested and developed all around the world. It allows the conversion of a coal seam into gas under in situ conditions of high temperature with the use of gasifying agents such as air, oxygen, steam or with a mixture of them. The paper presents the results of the analysis and assessment of a critical event during the process: a dangerous gas accumulation that occurred during an underground coal gasification experiment in the Experimental Mine “Barbara” of the Central Mining Institute (Poland). The UCG experiment using the shaft method is described, together with its monitoring system and the problems that appeared during the process. The application of the Fault Tree Methodology allowed the establishment of the main factors that may lead to the explosion and to present possible scenarios of its occurrence. Moreover, calculations were carried out to evaluate the risk level of explosion for the gas mixture and the minimum level of oxygen in the mixture that is necessary to initiate an explosion. These calculations were based on a modification of the formula proposed by Le Chatelier. During the course of the underground experiment, original information of the process behaviour has been acquired that can be used in the preparation of other UCG experiments in operational mines to guarantee the safety and the stability of the process.

For many applications such as environmental monitoring in the aftermath of a natural disaster and mountain search-and-rescue, swarms of autonomous Unmanned Aerial Vehicles (UAVs) have the potential to provide a highly versatile and often relatively inexpensive sensing platform. Their ability to operate as an ‘eye-in-the-sky’, processing and relaying real-time colour imagery and other sensor readings facilitate the removal of humans from situations which may be considered dull, dangerous or dirty. However, as with manned aircraft they are likely to encounter errors, the most serious of which may require the UAV to land as quickly and safely as possible. Within this paper we therefore present novel work on autonomously identifying Safe Landing Zones (SLZs) which can be utilised upon occurrence of a safety critical event. Safe Landing Zones are detected and subsequently assigned a safety score either solely using multichannel aerial imagery or, whenever practicable by fusing knowledge in the form of Ordnance Survey (OS) map data with such imagery. Given the real-time nature of the problem we subsequently model two SLZ detection options one of which utilises knowledge enabling the UAV to choose an optimal, viable solution. Results are presented based on colour aerial imagery captured during manned flight demonstrating practical potential in the methods discussed.

lthough uncontrolled diabetes can increase the risk for other comorbidities, some Adiagnoses are more common than others. Diabetes is associated with a variety of small and large vessel complications, such as retinopathy, nephropathy, neuropathy, and atherosclerosis. Some of this is explained by hypercoagulability, but the connection between diabetes and coagulation disorders still requires research. In this case study, a patient with newly diagnosed type 2 diabetes mellitus (T2DM) presented to the hospital initially with a critical diagnosis, requiring intensive care treatment. When this initial diagnosis was controlled, another life-threatening condition occurred, which was not initially linked to diabetes because it is not as common as other comorbidities. A quick response by the hospitalist nurse practitioners (NPs) and appropriate testing were the keys to arriving at the correct diagnosis and treatment, which prevented worsening morbidity and controlled the high potential for mortality from this critical event.

The interaction of circulating cells within the vascular wall is a critical event in chronic inflammatory processes, such as atherosclerosis, but the control of the vascular inflammatory state is still largely unclear. This study was undertaken to characterize the function of the endothelial

Due to the rapid exchange of information and large user base of social networking sites, these are focused for gathering the latest information or news from people over the world. Anyone having an internet connected device can share thoughts or update on real-time events. Social media helps reporters as well as common men in sharing useful information, but at the same time, it also leads to deliberate or accidental spread of rumors, i.e. pieces of information having uncertain truth at the time of posting. During social crisis, people access these platforms to get relevant information. In the rush of being early responders to a critical event users post the information even without checking its veracity and that further used by other users to fill-in their informational gap. So flagging out the unverified information can be useful in maintaining a distance from spreading the information that may end up being false. The openness of online social networking platforms (i.e. Twitter or Facebook), presence of machine learning and NLP (Natural Language Processing) based techniques give us a chance to inspect the conduct of people in posting rumorous information. In this work, we summarize and present the efforts and achievements so far to combat the spread of rumorous information. These efforts composed of analyzing the content of rumors, properties of users who share rumors and network structure that favor the spread of such information.

Statistics reveal a dearth of daughters among successors of family business owners. In one of very few empirical studies on the subject of daughters who do not follow in the footsteps of their entrepreneurial fathers, we examined factors that may contribute to daughters’ self-assessments of succession. Findings reveal that daughters’ own blindness to the possibility of succession, often resulting from automatically activated gender norms, impedes their ascendancy. Interviews with daughters who did not pursue executive positions with decision making responsibilities in their family firms, as well as both sons and daughters who did, indicate that daughters may not deliberately consider succession until a critical event motivates them to do so. Additionally, parental support and mentoring for leadership are seen to facilitate daughter succession.

The aggregation of the protein alpha-synuclein (α-SYN) is believed to be a critical event in Parkinson's disease (PD). α-SYN is characterized by a remarkable conformational plasticity, adopting different conformations depending on the environment. In vitro, α-SYN lacks a well-defined structure. Therefore, it was classified as an 'intrinsically disordered protein'. A debate has recently begun over how α-SYN behaves in the cell: is it an intrinsically disordered protein or a stable tetramer with a low propensity for aggregation? In this review, we discuss the aggregation of α-SYN and describe factors that influence this process and their potential relevance in PD pathogenesis. We address the ways in which aggregated α-SYN mediates toxicity and might lead to PD, and propose possible therapeutic strategies.

Background Recent studies in anaesthesia and intensive care indicate that a team's ability to adapt its coordination activities to changing situational demands is crucial for effective teamwork and thus, safe patient care. This study addresses the relationship between adaptation of team coordination and markers of clinical performance in response to a critical event, particularly regarding which types of coordination activities are used and which team member engages in those coordination activities. Methods Video recordings of 15 two-person anaesthesia teams (anaesthesia trainee plus anaesthesia nurse) performing a simulated induction of general anaesthesia were coded, using a structured observation system for coordination activities. The simulation involved a critical event'asystole during laryngoscopy. Clinical performance was assessed using two separate reaction times related to the critical event. Results Analyses of variance revealed a significant effect of the critical event on team coordination: after the occurrence of the asystole, team members adapted their coordination activities by spending more time on information management'a specific type of coordination activity (F1,28=15.17, P=0.001). No significant effect was found for task management. The increase in information management was related to faster decisions regarding how to respond to the critical event, but only for trainees and not for nurses. Conclusions Our findings support the claim that adaptation of coordination activities is related to improved team performance in healthcare. Moreover, adaptation and its relationship to team performance were found to vary with regard to type of coordination activities and team member.

A recent event-related potential (ERP) study (Thierry G., Martin, C.D., Downing, P., Pegna, A.J. 2007. Controlling for interstimulus perceptual variance abolishes N170 face selectivity. Nature Neuroscience, 10, 505-11) claimed that the larger occipito-temporal N170 response to pictures of faces than other categories -- the N170 effect -- is due to a methodological artifact in stimulus selection, specifically, a greater interstimulus physical variance between pictures of objects than faces in previous ERP studies which, when controlled, eliminates this N170 effect. This statement casts doubts on the validity of the conclusions reached by a whole tradition of electrophysiological experiments published over the past 15 years and questions the very interest of using the N170 to probe the time course of face processes in the human brain. Here we claim that this physical variance factor is ill-defined by Thierry et al. and cannot account for previous observations of a smaller N170 amplitude to nonface objects than faces without latency increase and component "smearing". Most importantly, this factor was controlled in previous studies that reported robust N170 effects. We demonstrate that the absence of N170 effect in the study of Thierry et al. is due to methodological flaws in the reported experiments, most notably measuring the N170 at the wrong electrode sites. Moreover, the authors attributed a modulation of N170 amplitude in their study to a differential interstimulus physical variance while it probably reflects a biased comparison of different quality sets of individual images. Here, by taking Thierry et al.'s study as an exemplar case of what should not be done in ERP research of visual categorization processes, we provide clarifications on a number of methodological and theoretical issues about the N170 and its largest amplitude to faces. More generally, we discuss the potential role of differential visual homogeneity of object categories as well as low-level visual properties versus high-level visual processes in accounting for early face-preferential responses and the question of the speed at which visual stimuli are categorized as faces. This survey of the literature points to the N170 as a critical event in the time course of face processes in the human brain.

Megaphyll leaf evolution was a critical event in Earth history that had major consequences for the biotic regulation of the global environment. Zimmermann's telome theory has been widely accepted for over seventy years as the leading explanation for this evolutionary innovation. According to the telome theory, megaphylls evolved from the three-dimensional lateral branches of early vascular land plants in a hypothetical series of three transformations; first, the formation of determinate lateral branches (overtopping); second, the development of 'flattened' branch systems (planation); and third, the fusion of planated branches with lateral outgrowths of photosynthetic mesophyll tissue to form the leaf blade (webbing). A critical review of the molecular and cellular evidence identifies plausible genetic, cellular and physiological mechanisms in extant higher plants for overtopping and planation but more limited evidence for the process of webbing (lateral outgrowth fusion). We highlight key outstanding questions concerning the telome theory that are likely to be resolved when gene identification and functional analysis techniques are applied to photosynthetic organisms that have different evolutionary histories.

During membrane fusion, the outer leaflets of the two membranes merge first, whereas the distal membrane leaflets remain separate until the opening of a fusion pore. This intermediate stage, called hemifusion, is a critical event shared by exocytosis, protein trafficking, and viral entry.

Surgeons have traditionally monitored mortality as part of their surgical practice. The aim of this study was to determine whether peer review surgical mortality data might be useful in appraisal.Since 1994, the Scottish Audit of Surgical Mortality (SASM) has performed critical event analysis of deaths under surgical care in Scotland. The anonymised, peer reviewed records of 16 consenting surgeons from a single Trust were reviewed over a three year period (2000-2002).Compliance with this voluntary audit was high at 97%. Individual surgeon profiles and comparison with colleagues in similar surgical practice demonstrated adverse events were infrequent and usually due to problems with the process of care rather than individual surgeon errors. The number of case note reviews requested increased significantly over the three years (chi square 9.5, p0.01) although there was no significant change in the mean number of deaths per surgeon (18) or mean number of adverse events per surgeon (4).The use of sequential individual peer reviewed mortality data for anonymised comparison with local colleagues is now in use in appraisal and has potential for the revalidation process. This could provide reassurance that individual surgeons are complying with the General Medical Council concept of "good clinical practice" and highlight local problems in the process of care.

JUSTIFICATIVA E OBJETIVOS: Em decorrência da grande evolução da monitorização e do arsenal terapêutico disponível nos últimos anos, houve uma redução na incidência de eventos adversos durante procedimentos anestésicos. Porém, continua importante o treinamento dos médicos residentes para este tipo de ocorrência. O objetivo deste estudo foi avaliar o desempenho prático do residente de Anestesiologia em eventos adversos durante uma anestesia simulada. MÉTODO: Foram avaliados 17 médicos em especialização do primeiro e segundo anos de Anestesiologia (ME1 e ME2) e 5 instrutores do Centro de Ensino e Treinamento (CET) do HCFMUSP (Título Superior em Anestesiologia - TSA). Foi utilizado o simulador computadorizado Anesthesia Simulator Consultant (ASC) versão 2.0 - 1995/Anesoft para realização das simulações dos eventos. Os incidentes críticos escolhidos foram fibrilação ventricular (FV) e choque anafilático. Após a realização da simulação, foram impressos os resultados de cada participante e avaliadas e pontuadas as condutas adotadas para resolver os incidentes críticos pré-determinados. Os participantes avaliaram o simulador através do preenchimento de um questionário. RESULTADOS: Não houve diferença estatística entre as médias obtidas pelos grupos, porém notou-se uma tendência de melhor desempenho dos grupos TSA e ME2 na simulação de FV. Com relação ao choque anafilático, houve uma tendência de melhor desempenho do grupo TSA. CONCLUSÕES: O treinamento para diagnóstico e condutas em eventos adversos deve ser foco de atenção durante o treinamento de médicos residentes e na atualização de anestesiologistas. O uso do simulador pode ser uma das formas de realizar o treinamento nestas situações. BACKGROUND AND OBJECTIVES: Because of monitoring and drugs evolution, there has been a decrease in the incidence of critical events during anesthetic procedures. Despite this low frequency, critical event training for Anesthesiology residents remains important. This study aimed at evaluating Anesthesiology residents' critical care skills during computer-simulated anesthesia. METHODS: Seventeen anesthesiology residents (first and second year) and 5 anesthesiology instructors were evaluated. Using the Anesthesia Simulator Consultant (2.0 - 1995/Anesoft) simulations of ventricular fibrillation (VF) and anaphylactic reaction (AR) were performed. After simulation, results of each participant were printed and approaches to solve predetermined critical events were evaluated and scored. Participants have evaluated the simulator by filling out a questionnaire. RESULTS: There were no significant differences in means obtained by groups, but there has been a trend toward better performance of second year residents and Anesthesiology instructors during VF simulation. There has been a trend toward better performance of Anesthesiology instructors during AR simulation. CONCLUSIONS: Critical events management training should be the focus during residents and anesthesiologists training. Computer simulation could be a way to carry out such training. JUSTIFICATIVA Y OBJETIVOS: Con la decurrencia de la grande evolución de la monitorización y del arsenal terapéutico disponible en los últimos años, hubo una reducción en la incidencia de eventos adversos durante los procedimientos anestésicos. Sin embargo, continua importante el entrenamiento de los médicos practicantes para este tipo de ocurrencia. El objetivo de este estudio fue evaluar el desempeño práctico de los médicos practicantes de Anestesiología en eventos adversos durante una anestesia simulada. MÉTODO: Fueron evaluados 17 médicos en especialización de primero y segundo años de Anestesiología (ME1 y ME2) y 5 instructores del Centro de Enseñanza y Entrenamiento (CEE) del HCFMUSP (Título Superior en Anestesiología - TSA). Fue utilizado el simulador computadorizado Anesthesia Simulator Consultant (ASC) versión 2.0 - 1995/Anesoft para realización de las simulaciones de los eventos. Los incidentes críticos escogidos fueron fibrilación ventricular (FV) y choque anafiláctico. Después de la realización de la simulación, fueron impresos los resultados de cada participante, evaluados y puntuados las conductas adoptadas para resolver los incidentes críticos pre-determinados. Los participantes evaluaron el simulador a través de un cuestionario para ser respondido. RESULTADOS: No hubo diferencia estadística entre las medias obtenidas por los grupos, sin embargo, se notó una tendencia de un desempeño mejor de los grupos TSA y ME2 en la simulación de FV. En relación al choque anafiláctico, hubo una tendencia de desempeño mejor del grupo TSA. CONCLUSIONES: El entrenamiento para el diagnóstico y conductas en eventos adversos debe ser un foco de atención durante el entrenamiento de médicos practicantes y en la actualización de anestesiologistas. El uso del simulador puede ser una de las formas de realizar el entrenamiento en estas situaciones.

An intact vascular endothelium is critical to the maintenance of normal arterial tone and coagulation status. Endothelial injury leading to dysfunction is thought to be a precursor to most if not all vascular disease, and has been implicated as a critical event in atherosclerosis. At present there are several methods available for detection of in vivo endothelial function, and the aim of this study was to critically review these methods. Five distinct methods were identified and studied in detail. These methods are diverse and each assesses a different vascular bed. Importantly there is no uniformity among investigators over choice of method and protocol, making it difficult to compare in vivo enothelial dysfunction between groups. These issues need to be addressed in large scale comparative analyses so that investigators can agree a common approach to endothelial function assessment.

The amyloid hypothesis of Alzheimer's disease (AD) maintains that the accumulation of the amyloid β protein (Aβ) is a critical event in disease pathogenesis. A great deal of both academic and commercial research has focused on the mechanisms by which Aβ is generated. However, investigations into the mechanisms underlying Aβ clearance have blossomed over the last several years. This minireview will summarize pathways involved in the removal of cerebral Aβ, including enzymatic degradation and receptor-mediated efflux out of the brain.

The Stockholm-Uppsala region is claimed to be one of the worlds’ most expansive biomedical regions, both when it concerns scientific and business activities. Or, as it was formulated in a special section in Nature, October 2001: p. 6. “A world class scientific & business environment”. A common explanation to the growing commercial activities in the Uppsala region has been a critical event within the cluster; the restructuring the pharmaceutical company Pharmacia. However, research focus on how resources are combined results in an almost opposite picture. It is in interaction with stable and healthy industrial and academic units that new projects/companies develop. Furthermore, this interacting seems not to be restricted to a biomedical cluster, but stretches over several different places and industrial areas.

An elastic–plastic three-dimensional finite element method analysis is used to determine the stress and strain distributions ahead of notches of four-point bending (4PB) specimens with various sizes (W, B and a) and widths (B). By measuring the location of the cleavage initiation sites for a C–Mn steel, the local cleavage fracture stress σf is accurately determined. With increasing specimen sizes and widths the fracture load Pf increases considerably, but σf remains nearly constant. The reason that the σf of the specimen with minimum size is slightly larger than that of the other specimens is analyzed by an active zone model of cleavage fracture for notched specimens. The critical event for cleavage fracture is the propagation of a ferrite grain-sized crack into the neighboring matrix, and is independent of specimen sizes and widths. σf is mainly determined by the length of the critical microcrack, and the specimen sizes and widths have little effect on it.

The analysis of eye movements can provide rich information about driver's attention and the course of behaviour in hazardous situations. We present data from a driving simulation study showing that the switching between preattentive and attentive processing is reflected in visual fixations. For this initial analysis, we considered fixations from the perspective of their duration and the amplitude of related saccades. Since fixation durations may change instantaneously from one fixation to the next, we further selected the temporal vicinity of the emerging hazard for a closer analysis of fixations around this time. With this second type of analysis, the fixations that actually “detect” a critical event can be discovered and their duration measured. Upon detection of an immediate hazard, there is an increase in fixation duration and a corresponding increase in occurrence of attentive fixations on the cost of preattentive ones. This switching from one level of processing to another is recognisable on a short, phasic time scale. We finally discuss attentional conditions where overlooked or not sufficiently processed hazards do not lead to the appropriate breaking reaction on the part of the driver.

The transition from vegetative to reproductive growth is a critical event in the life cycle of plants. Previous physiological studies have deduced that hormone-like substances mediate this important transition but the biochemical nature of the putative signaling molecules has remained elusive. Recent molecular and genetic studies of key flowering-time genes offer new approaches to understanding the mechanisms underlying the initiation of flowering.

Background: Many patients undergo abdominal imaging for non-specific symptoms. An increasing number of these patients are discovered to have incidental adrenal or retroperitoneal tumours. Approximately 5% of all incidentally detected adrenal lesions are phaeochromocytomas and 25% of phaeochromocytomas are discovered during imaging studies for unrelated disorders. 10% of phaeochromocytomas are extra-adrenal. Methods: Retrospective case notes review of three patients with adrenal/retroperitoneal lesions who had percutaneous biopsy before biochemical testing and tertiary referral. Findings: Adrenal/retroperitoneal lesions are still being biopsied without prior biochemical testing. One patient with phaeochromocytoma had a critical event. The others were found to have a phaeochromocytoma and a ganglioneuroma. Conclusions: The possibility of a catecholamine secreting tumour should be considered in adrenal and extra-adrenal retroperitoneal lesions. If a biopsy is planned, rarely required in adrenal lesions, phaeochromocytoma must be excluded by biochemical testing prior to the biopsy to avoid potential life threatening complications.

Fracture mechanics tests of welds and ferritic steels in the brittle to ductile region often show a phenomenon called pop-in, a process of trigger and arrest of a brittle crack. Regarding pop-in initiation as a critical event results in too conservative values of fracture toughness. Different pop-in treatment proposals taken from the literature are analyzed in this paper. The degree of conservatism of the pop-in assessment procedures issued in some fracture toughness test standards is also analyzed. An alternative proposal for the analysis of the pop-in significance in SENB CTOD tests is introduced. This method is based on the change in elastic compliance, and it allows the evaluation of any pop-in, even those that are preceded by ductile crack growth or previously ignored pop-ins. The relaxation of the maximum pop-in crack extension implicit in both ASTM and BSI procedures (Δap

The intrauterine contraceptive device (IUCD) has been a method of contraception used for centuries worldwide. Although the IUCD is a widely accepted and utilized method of contraception throughout Europe and China only 0.8% of women in North America aged 15 to 44 years are using the IUCD for contraception. In a 1999 survey 9% to 24% of women in five European countries and 33% of Chinese women using contraception were utilizing the IUCD. Misconceptions regarding the IUCD likely propagated by the circumstances surrounding the Dalkon Shield in the 1970s may be the critical event leading to practitioners apprehension of recommending the IUCD as a safe and effective contraceptive method. (excerpt)

Recent findings indicate that activated T lymphocytes, showing restricted T-cell receptor repertoire and a Th1-like profile of cytokine production, are responsible for macrophage activation and release of inflammatory cytokines, toxic oxygen metabolites and nitric oxide, which initiate and maintain the transmural intestinal inflammation in Crohn's disease. A critical event in the promotion of Th1-type response at gut level may involve up-regulation of IL-12 production and the breakdown of tolerance against the intestinal flora.

Loss of lysosomal integrity is a critical event for killing tumor cells in the photodynamic therapy of cancers. To elucidate the mechanism of photodamage induced lysosomal disintegration, we investigated the role of losing lysosomal proton translocation in latency loss of photosensitized lysosomes. Isolated rat liver lysosomes were light exposed in the presence of Methylene blue. Through monitoring lysosomal delta pH with Acridine orange and measuring its membrane potential with 3,3'-dipropylthiadicarbocyanine iodide, loss of Mg-ATP dependent proton translocation and decrease in electrogenicity of the proton pump were observed after lysosomes were photosensitized. When normal lysosomes were incubated for 60 min in K+ contained medium, percentage free activity of lysosomal enzyme beta-galactosidase increased, i.e. lysosomal latency decreased. In the presence of Mg-ATP, the latency loss of incubated lysosomes reduced. Addition of n-ethylmaleimide, a potent inhibitor of lysosomal H(+)-ATPase, abolished the effect of Mg-ATP on lysosomal latency. It suggests a role of proton translocation in protecting lysosomal integrity. Under the same conditions, Methylene blue photosensitized lysosomes increasingly lost latency of beta-hexosaminidase and beta-galactosidase with light exposure, presumably due to the photodamage induced loss of proton pumping. In contrast, the photosensitization did not decrease lysosomal latency in the absence of Mg-ATP, implying that lysosomal integrity might not be impaired via other photodamage effects under the conditions of this study. These results indicate that lysosomal integrity can be photodestructed via the loss of proton translocation.

The breaking of tolerance to self-antigens, involving the activation of self-reactive lymphocytes, is a critical event leading to autoimmune disease. The precise mechanisms by which this occurs are unknown, but among other etiological factors, viruses have been implicated. Recent results with animal models of insulin-dependent diabetes provide insight into how viruses induce autoimmune disease.

How do organizations learn from a drastic failure? We distinguish between ad-hoc and systematic reactions and discuss their effectiveness for dealing with two basic challenges: (1) identifying and solving the problems that caused the failure; and (2) changing the organization accordingly. We apply this conceptual perspective to illustrate the dynamics of learning from the drastic failure that occurred during the development of the Airbus A380 “superjumbo.” Our findings echo extant observations that efforts to redesign organizational behavior in an ad-hoc manner are often insufficient. Instead, the organizational system must provide a scaffolding that allows experiencing a critical event in a rich and systematic manner. When seen from a dynamic perspective, however, we find that even imperfect ad-hoc efforts may play a vital role. By enforcing changes, providing stability, and raising awareness, they can act as a helpful prelude to more systematic problem solving and change.

Ciliary movement is powered by axonemal dynein. This article considers how a signal transduction cascade initiated at the cell membrane may activate outer dynein arms to change the velocity of microtubule sliding and the swimming speed of ciliated cells. For Paramecium, a critical event in the cascade is the cAMP-dependent phosphorylation of a 29 kDa polypeptide that is associated with the outer dynein arm.