Artículos de revistas: "Loss of control events"

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Hess, Ronald A. "A model for pilot control behavior in analyzing potential loss-of-control events". Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 228, n.º 10 (8 de abril de 2014): 1845–56. http://dx.doi.org/10.1177/0954410014531218.

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Ud-Din, Sameer y Yoonjin Yoon. "Analysis of Loss of Control Parameters for Aircraft Maneuvering in General Aviation". Journal of Advanced Transportation 2018 (2018): 1–19. http://dx.doi.org/10.1155/2018/7865362.

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A rapid increase in the occurrence of loss of control in general aviation has raised concern in recent years. Loss of control (LOC) pertains to unique characteristics in which external and internal events act in conjunction. The Federal Aviation Administration (FAA) has approved an Integrated Safety Assessment Model (ISAM) for evaluating safety in the National Airspace System (NAS). ISAM consists of an event sequence diagram (ESD) with fault trees containing numerous parameters, which is recognized as casual risk model. In this paper, we outline an integrated risk assessment framework to model maneuvering through cross-examining external and internal events. The maneuvering is in the critical flight phase with a high number of LOC occurrences in general aviation, where highly trained and qualified pilots failed to maintain aircraft control irrespective of the preventive nature of the events. Various metrics have been presented for evaluating the significance of these parameters to identify the most important ones. The proposed sensitivity analysis considers the accident, fatality, and risk reduction frequencies that assist in the decision-making process and foresees future risks from a general aviation perspective.

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Milosavljevic, Stephan, David I. McBride, Nasser Bagheri, Radivoj M. Vasiljev, Allan B. Carman, Borje Rehn y Dave Moore. "Factors associated with quad bike loss of control events in agriculture". International Journal of Industrial Ergonomics 41, n.º 3 (mayo de 2011): 317–21. http://dx.doi.org/10.1016/j.ergon.2011.02.010.

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4

Volkanovski, Andrija y Miguel Peinador Veira. "Analysis of Loss of Essential Power System Reported in Nuclear Power Plants". Science and Technology of Nuclear Installations 2018 (9 de julio de 2018): 1–21. http://dx.doi.org/10.1155/2018/3671640.

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The essential power supply system is important for the nuclear safety and accident mitigation of the currently operating nuclear power plants. This system provides electrical power to the essential instrumentation and control systems of the nuclear power plant when all alternate current power sources are lost. This event is known as station blackout (SBO) event. Operational events of failure or deficiency of the essential power supply system are analyzed in this paper. The relevant events were searched and identified in four databases of operational events. The report includes events identified in French SAPIDE and German VERA operational events records for the time period 1996 to 2015. The International Atomic Energy Agency (IAEA) IRS and Nuclear Regulatory Commission (NRC) LER operational events databases were screened for relevant events that occurred in the period between 2000 and 2016. In total, 308 relevant events are identified in the SAPIDE, 103 in VERA, 56 in LER, and 15 in IRS operational events database. Classification and in-depth analysis were done on the identified events considering the following predefined categories: the plant status during the event, circumstances, affected equipment, cause of the event (direct and root), and implications of the event on plant safety. Main findings from the evaluation of the events are presented. Observations of the causes resulting in the events and potential actions that can decrease the number and consequences of the events are presented.

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Rheinberger, C. M., H. E. Romang y M. Bründl. "Proportional loss functions for debris flow events". Natural Hazards and Earth System Sciences 13, n.º 8 (30 de agosto de 2013): 2147–56. http://dx.doi.org/10.5194/nhess-13-2147-2013.

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Abstract. Quantitative risk assessments of debris flows and other hydrogeological hazards require the analyst to predict damage potentials. A common way to do so is by use of proportional loss functions. In this paper, we analyze a uniquely rich dataset of 132 buildings that were damaged in one of five large debris flow events in Switzerland. Using the double generalized linear model, we estimate proportional loss functions that may be used for various prediction purposes including hazard mapping, landscape planning, and insurance pricing. Unlike earlier analyses, we control for confounding effects of building characteristics, site specifics, and process intensities as well as for overdispersion in the data. Our results suggest that process intensity parameters are the most meaningful predictors of proportional loss sizes. Cross-validation tests suggest that the mean absolute prediction errors of our models are in the range of 11%, underpinning the accurateness of the approach.

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6

Thomas, B. J. y R. Rothstein. "The genetic control of direct-repeat recombination in Saccharomyces: the effect of rad52 and rad1 on mitotic recombination at GAL10, a transcriptionally regulated gene." Genetics 123, n.º 4 (1 de diciembre de 1989): 725–38. http://dx.doi.org/10.1093/genetics/123.4.725.

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Abstract We have previously shown direct-repeat recombination events leading to loss of a plasmid integrated at the GAL10 locus in Saccharomyces cerevisiae are stimulated by transcription of the region. We have examined the role of two recombination- and repair-defective mutations, rad1 and rad52, on direct repeat recombination in transcriptionally active and inactive sequences. We show that the RAD52 gene is required for transcription-stimulated recombination events leading to loss of the integrated plasmid. Similarly, Gal+ events between the duplicated repeats that retain the integrated plasmid DNA (Gal+ Ura+ replacement events) are reduced 20-fold in the rad52 mutant in sequences that are constitutively expressed. In contrast, in sequences that are not expressed, the rad52 mutation reduces plasmid loss events by only twofold and Gal+ Ura+ replacements by fourfold. We also observe an increase in disome-associated plasmid loss events in the rad52 mutant, indicative of chromosome gain. This event is not affected by expression of the region. Plasmid loss events in rad1 mutant strains are reduced only twofold in transcriptionally active sequences and are not affected in sequences that are repressed. However, the rad1 and rad52 double mutant shows a decrease in plasmid loss events greater than the sum of the decreases in the rates of this event displayed by either single mutant in both constitutive and repressed DNA, indicating a synergistic interaction between these two genes. The synergism is limited to recombination since the rad1 rad52 double mutant is no more sensitive when compared with either single mutant in its ability to survive radiation damage. Finally, the recombination pathway that remains in the double mutant is positively affected by transcription of the region.

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7

Clay, Lynne, Gareth J. Treharne, E. Jean C. Hay-Smith y Stephan Milosavljevic. "Are agricultural quad bike loss-of-control events driven by unrealistic optimism?" Safety Science 66 (julio de 2014): 54–60. http://dx.doi.org/10.1016/j.ssci.2014.02.002.

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8

Yao, Li, Yongfeng Li, Zhaoqiang Qian, Meilin Wu, Haifan Yang, Naijia Chen, Yanning Qiao et al. "Loss of control over mild aversive events produces significant helplessness in mice". Behavioural Brain Research 376 (diciembre de 2019): 112173. http://dx.doi.org/10.1016/j.bbr.2019.112173.

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9

Rohith, G. y Nandan K. Sinha. "Improved pilot training via bifurcation analysis and robust control for aircraft loss of control problems". Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 233, n.º 14 (8 de mayo de 2019): 5414–27. http://dx.doi.org/10.1177/0954410019846434.

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Aircraft loss of control is one of the largest contributors to fatal accidents in the aviation environment. The unprecedented change in aircraft dynamics due to loss of control onset and the associated structural constraints make loss of control prevention and/or recovery a challenging task. State-of-the-art autopilots are generally designed for nominal aircraft operations and disengage under off-nominal conditions, hence cannot be viewed as a safety solution during loss of control onsets. Herein lies the importance of providing training to pilots so as to equip themselves to rescue aircraft from loss of control events. Current pilot training methodologies have significant limitations when it comes to loss of control prevention and recovery strategies. In this context, a simulator for improved pilot training based on bifurcation and continuation techniques is presented in the paper. Augmenting these techniques with the current pilot training procedure can significantly improve the quality of training. This methodology can help pilots to distinguish various loss of control scenarios and aid them in taking appropriate recovery decisions intuitively. Meanwhile, a robust control-based loss of control handling module is also presented for developing non-intuitive strategies for loss of control prevention and recovery. This module can simulate adequate control profiles that the pilot can follow to get in and out of various loss of control scenarios. Moreover, it can be used as pilot activated recovery system in case of pilot disorientation and as a fully autonomous recovery system for much complex scenarios. The simulator is developed in MATLAB/SIMULINK platform and is shown to realize diverse loss of control events like spiral, spin, etc., and subsequent recovery from the same.

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FARMER, ANNE E. y PETER McGUFFIN. "Humiliation, loss and other types of life events and difficulties: a comparison of depressed subjects, healthy controls and their siblings". Psychological Medicine 33, n.º 7 (25 de septiembre de 2003): 1169–75. http://dx.doi.org/10.1017/s0033291703008419.

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Background. It has been proposed that adverse life events involving loss or humiliation are particularly potent in provoking depressive episodes. We have also previously suggested that experiencing high rates of non-severe events may play a role in the development of resilience to the impact of severe threatening events when these occur.Method. The Life Events and Difficulties Schedule (LEDS) (Brown & Harris, 1978) was used to record the life events experienced by 108 depressed probands and their nearest aged siblings as well as 105 healthy control subjects and their nearest aged siblings. All subjects were interviewed using the Schedule for the Clinical Assessment of Neuropsychiatry (SCAN) (Wing et al. 1990).Results. Depressed probands were significantly more likely to have experienced a severe threatening event, loss event, or a humiliation event compared to the other subjects. These events also made up a greater proportion of the total number of events, in the depressed probands. Humiliation events were more frequent in depressed men than depressed women. There were no differences between the four groups for experiencing a non-severe event, although depressed probands also experienced more difficulties than the other three groups. Fifty-six healthy subjects who had not become depressed despite having experienced at least one severe and threatening event, had significantly more non-severe events, than the 116 subjects who were depressed at the time of interview.Conclusions. The findings support the hypothesis that loss and humiliation events are particularly depressogenic. Experiencing a high rate of non-severe events may be associated with resilience to becoming depressed in the face of a threatening event.

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York, Janine, Thomas Nicholson, Patricia Minors y David F. Duncan. "Stressful Life Events and Loss of Hair among Adult Women, a Case-Control Study". Psychological Reports 82, n.º 3 (junio de 1998): 1044–46. http://dx.doi.org/10.2466/pr0.1998.82.3.1044.

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A case-control design was used to compare stress (as measured with the Social Readjustment Rating Scale) in the lives of 25 women who had experienced recent, unexplained hair loss with that of 25 women with no hair loss. High stress was reported by 22 of the women experiencing hair loss and 10 not experiencing hair loss. An odds ratio of 11 suggests that women who experience high stress are 11 times more likely to experience hair loss. Replication is encouraged.

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12

Kontogiannis, Tom y Stathis Malakis. "Strategies in controlling, coordinating and adapting performance in air traffic control: modelling ‘loss of control’ events". Cognition, Technology & Work 15, n.º 2 (28 de diciembre de 2011): 153–69. http://dx.doi.org/10.1007/s10111-011-0209-0.

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13

Chen, Xiaoliang, Gaiyun Liu, Naiqi Wu, Abdulrahman M. Al-Ahmari, Abdulaziz Mohammed El-Tamimi y Emad S. Abouel Nasr. "Confusion Control in Generalized Petri Nets Using Synchronized Events". Mathematical Problems in Engineering 2015 (2015): 1–23. http://dx.doi.org/10.1155/2015/636959.

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The loss of conflicting information in a Petri net (PN), usually called confusions, leads to incomplete and faulty system behavior. Confusions, as an unfortunate phenomenon in discrete event systems modeled with Petri nets, are caused by the frequent interlacement of conflicting and concurrent transitions. In this paper, confusions are defined and investigated in bounded generalized PNs. A reasonable control strategy for conflicts and confusions in a PN is formulated by proposing elementary conflict resolution sequences (ECRSs) and a class of local synchronized Petri nets (LSPNs). Two control algorithms are reported to control the appeared confusions by generating a series of external events. Finally, an example of confusion analysis and control in an automated manufacturing system is presented.

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Nyberg, Ulf, Bengt Andersson y Henrik Aspegren. "Real time control for minimizing effluent concentrations during storm water events". Water Science and Technology 34, n.º 3-4 (1 de agosto de 1996): 127–34. http://dx.doi.org/10.2166/wst.1996.0425.

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Increased flow rates due to stormwater at the Klagshamn wastewater treatment plant occasionally cause hydraulic overloading of the activated sludge process resulting in sludge loss from the secondary clarifiers. To minimize these problems different operational strategies have been evaluated at the plant. Practical experiences have shown the benefits of using in-line storage for flow equalization even if the available volumes may seem small in comparison to the total daily flow rate during stormwater occasions. Step feed operation at the treatment plant can be used to further ease the problems with sludge loss. By-pass of primary treated wastewater can finally be used to avoid hydraulic overloading of the biological treatment process. By combining these strategies in a real time control system, the need for erecting off-line storage volumes can be minimized.

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15

Sime, Louise C., Peter O. Hopcroft y Rachael H. Rhodes. "Impact of abrupt sea ice loss on Greenland water isotopes during the last glacial period". Proceedings of the National Academy of Sciences 116, n.º 10 (13 de febrero de 2019): 4099–104. http://dx.doi.org/10.1073/pnas.1807261116.

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Greenland ice cores provide excellent evidence of past abrupt climate changes. However, there is no universally accepted theory of how and why these Dansgaard–Oeschger (DO) events occur. Several mechanisms have been proposed to explain DO events, including sea ice, ice shelf buildup, ice sheets, atmospheric circulation, and meltwater changes. DO event temperature reconstructions depend on the stable water isotope (δ18O) and nitrogen isotope measurements from Greenland ice cores: interpretation of these measurements holds the key to understanding the nature of DO events. Here, we demonstrate the primary importance of sea ice as a control on Greenland ice coreδ18O: 95% of the variability inδ18O in southern Greenland is explained by DO event sea ice changes. Our suite of DO events, simulated using a general circulation model, accurately captures the amplitude ofδ18O enrichment during the abrupt DO event onsets. Simulated geographical variability is broadly consistent with available ice core evidence. We find an hitherto unknown sensitivity of theδ18O paleothermometer to the magnitude of DO event temperature increase: the change inδ18O per Kelvin temperature increase reduces with DO event amplitude. We show that this effect is controlled by precipitation seasonality.

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Streeck, Hendrik, Bin Li, Art F. Y. Poon, Arne Schneidewind, Adrianne D. Gladden, Karen A. Power, Demetre Daskalakis et al. "Immune-driven recombination and loss of control after HIV superinfection". Journal of Experimental Medicine 205, n.º 8 (14 de julio de 2008): 1789–96. http://dx.doi.org/10.1084/jem.20080281.

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After acute HIV infection, CD8+ T cells are able to control viral replication to a set point. This control is often lost after superinfection, although the mechanism behind this remains unclear. In this study, we illustrate in an HLA-B27+ subject that loss of viral control after HIV superinfection coincides with rapid recombination events within two narrow regions of Gag and Env. Screening for CD8+ T cell responses revealed that each of these recombination sites (∼50 aa) encompassed distinct regions containing two immunodominant CD8 epitopes (B27-KK10 in Gag and Cw1-CL9 in Env). Viral escape and the subsequent development of variant-specific de novo CD8+ T cell responses against both epitopes were illustrative of the significant immune selection pressures exerted by both responses. Comprehensive analysis of the kinetics of CD8 responses and viral evolution indicated that the recombination events quickly facilitated viral escape from both dominant WT- and variant-specific responses. These data suggest that the ability of a superinfecting strain of HIV to overcome preexisting immune control may be related to its ability to rapidly recombine in critical regions under immune selection pressure. These data also support a role for cellular immune pressures in driving the selection of new recombinant forms of HIV.

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17

Döscher, R. y T. Koenigk. "Arctic rapid sea ice loss events in regional coupled climate scenario experiments". Ocean Science Discussions 9, n.º 4 (9 de julio de 2012): 2327–73. http://dx.doi.org/10.5194/osd-9-2327-2012.

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Abstract. Rapid sea ice loss events (RILEs) in a mini-ensemble of regional Arctic coupled climate model scenario experiments are analyzed. Mechanisms of sudden ice loss are strongly related to atmospheric circulation conditions and preconditioning by sea ice thinning during the seasons and years before the event. Clustering of events in time suggests a strong control by large scale atmospheric circulation. Anomalous atmospheric circulation is forcing ice flow and providing warm air affecting winter ice growth. Even without a seasonal preconditioning during winter, ice drop events can be initiated by anomalous inflow of warm air from the Atlantic sector during summer. It is shown that RILE events can be generated solely based on atmospheric circulation changes without possible competing mechanisms, such as anomalous seasonal radiative forcing or short-lived forcers (e.g. soot). Such forces do merely play minor roles or no role at all in our model. Mechanisms found are qualitatively in line with observations of the 2007 RILE.

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18

Rand, Margaret L., Hong Wang, K. W. Annie Bang, Jerome M. Teitel, Victor S. Blanchette, Alan T. Nurden y John Freedman. "Apoptotic-Like Events in Bernard-Soulier Syndrome (BSS) Platelets." Blood 112, n.º 11 (16 de noviembre de 2008): 1235. http://dx.doi.org/10.1182/blood.v112.11.1235.1235.

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Abstract Although anucleate, platelets are recognized to undergo apoptotic-like events, with some characteristics of activated platelets resembling those of apoptotic nucleated cells, e.g. membrane blebbing (microparticle (MP) formation), exposure of phosphatidylserine (PS). There are reports in the older literature that platelets from BSS patients expose more PS and have enhanced senescence. In the present study, using flow cytometry, we investigated apoptotic-like events, specifically PS exposure, MP formation, cell shrinkage and loss of mitochondrial inner membrane potential (ΔΨm) in platelets from 2 BSS patients (BSS-Ps), compared with platelets from a patient with another inherited macrothrombocytopenia - an MYH9-related disorder (MYH9-RD-P) - and from normal controls. Investigations were done using whole blood to avoid platelet manipulation, especially of the large platelets. Citrated blood was mixed with GPRP and Ca2+, and the agonists collagen (C; 20 μg/mL), thrombin (T; 1 U/mL), SFLLRN (PAR1 activating peptide (AP); 50 μM), AYPGKF (PAR4 AP; 250 μM), or combinations of C with T or the PAR APs. Platelets and MPs were identified as CD41-positive events; platelet size was expressed as median forward scatter (mFSC); MPs were defined as events <0.8 μm; PS exposure was measured as the % platelets with bound fluorescently-labeled annexin A5 and the mean fluorescence intensity (MFI) of bound annexin A5; and loss of ΔΨm was determined by decreased fluorescence of the potential-sensitive probe TMRM concurrently with PS exposure. Resting BSS and MYH9-RD platelets were larger than controls (mFSC of BSS-Ps: 136, 163; MYH9-RD-P: 126; controls: 50±2). Slightly more resting BSS platelets exposed PS than controls, as did MYH9-RD platelets (Table). Activation with C significantly increased the % platelets exposing PS, which was synergistically increased by T or the PAR1 and/or PAR4 APs; more BSS and MYH9-RD platelets exposed PS than did corresponding activated controls (Table). % PS Exposure Agonist(s) BSS-P1 BSS-P2 MYH9-RD-P controls none (resting platelets) 3.0 3.5 3.0 1.3±0.4 C 27.0 29.9 37.9 7.0±1.5 C+T 11.3 35.3 64.5 13.5±1.7 C+PAR1 AP 20.1 43.6 49.5 16.4±3.1 C+PAR4 AP 31.6 47.8 49.7 18.4±3.7 C+PAR1 AP+PAR4 AP 33.4 49.5 54.8 20.6±3.4 Interestingly, the platelets in the PS-exposing subpopulation were small (mFSC of BSS-Ps: 27, 30; MYH9-RD: 32; controls 18±1) and the annexin A5 MFI of this subpopulation of BSS and MYH9-RD platelets was .5-fold higher than that of controls irrespective of the platelet agonist(s). Unstimulated blood samples from patients and controls had 1–2% MPs; adding combinations of agonists led to the highest MP production, with control platelets producing 5–6% MPs, and BSS and MYH9-RD platelets, a 1.5–2.5-fold greater amount. Another apoptosis hallmark, cell shrinkage, was observed upon platelet activation in the non-PS-exposing population; in response to the various agonists, the size of this platelet population in patients and controls correlated inversely with the amount of PSexposing platelets formed (P<0.0.001) and the amount of MPs formed (P<0.0.001). In nucleated cells, dissipation of ΔΨm precedes PS exposure. However, activated BSS, MYH9-RD and control platelets exposed PS with or without a dissipated ΔΨm; ~50% of activated PS-exposing platelets did not exhibit loss of ΔΨm. While only 5–10% of activated non-PS-exposing control or MYH9-RD platelets exhibited ΔΨm loss, a substantial proportion, ~50%, of activated non-PS-exposing BSS platelets had a dissipated ΔΨm; in a rabbit model, we have previously found non-PS-exposing platelets with a collapsed ΔΨm to be associated with platelet senescence. In summary, we show that: PAR1 and PAR4 mediate the synergistic effect of T on C-stimulated PS expression on BSS, MYH9-RD and control platelets; the apoptotic-like event of cell shrinkage occurs in BSS platelets as well as MYH9-RD and control platelets; other such events, PS exposure and MP formation, are enhanced in BSS platelets compared with controls likely due to the large size of BSS platelets since they are also observed in MYH9-RD platelets; activation to expose PS can occur independently of ΔΨm dissipation in BSS, MYH9-RD and control platelets; and the loss of ΔΨm in non-PS-exposing platelets, an apoptotic-like event that is associated with platelet senescence and one that occurs only to a limited extent in MYH9-RD and control platelets, is a previously unrecognized characteristic of BSS platelets.

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Atefi, Najmossadat, Razieh Soltani-Arabshahi y Azizeh Afkham-Ebrahimi. "Stressful Life Events and Diffuse Unexplained Hair Loss in Women: A Case-Control Study". Dermatology 213, n.º 1 (2006): 44–45. http://dx.doi.org/10.1159/000092838.

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20

Huertas-Leyva, Pedro, Giovanni Savino, Niccolò Baldanzini y Marco Pierini. "Loss of Control Prediction for Motorcycles during Emergency Braking Maneuvers Using a Supervised Learning Algorithm". Applied Sciences 10, n.º 5 (4 de marzo de 2020): 1754. http://dx.doi.org/10.3390/app10051754.

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The most common evasive maneuver among motorcycle riders and one of the most complicated to perform in emergency situations is braking. Because of the inherent instability of motorcycles, motorcycle crashes are frequently caused by loss of control performing braking as an evasive maneuver. Understanding the motion conditions that lead riders to start losing control is essential for defining countermeasures capable of minimizing the risk of this type of crashes. This paper provides predictive models to classify unsafe loss of control braking maneuvers on a straight line before becoming irreversibly unstable. We performed braking maneuver experiments in the field with motorcycle riders facing a simulated emergency scenario. The latter involved a mock-up intersection in which we generated conflict events between the motorcycle ridden by the participants and an oncoming car driven by trained research staff. The data collected comprises 165 braking trials (including 11 trials identified as loss of control) with 13 riders representing four categories of braking skill, ranging from beginner to expert. Three predictive models of loss of control events during braking trials, going from a basic model to a more advanced one, were defined using logistic regressions as supervised learning methods and using the area under the receiver operating characteristic (ROC) curve as a performance indicator. The predictor variables of the models were identified among the parameters of the vehicle kinematics. The best model predicted 100% of the loss of control and 100% of the full control cases. The basic and the more advanced supervised models were adapted for loss of control identification with time series data, and the results detecting in real-time the loss of control events showed excellent performance as well as with the supervised models. The study showed that expert riders may maintain stability under dynamic conditions that normally lead less skilled riders to a loss of control or falling events. The best decision thresholds of the most relevant kinematic parameters to predict loss of control have been defined. The thresholds of parameters that typically characterize the loss of control such as the yaw rate and front-wheel lock duration were dependent on the rider skill levels. The peak-to-root-mean-square ratio of roll acceleration was the most robust parameter for identifying loss of control among all skill levels.

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21

Blower, Daniel, John Woodrooffe, Paul Green, Anne Matteson y Michael Shrank. "Determination of Events Leading to Sport Utility Vehicle Rollover". Transportation Research Record: Journal of the Transportation Research Board 1908, n.º 1 (enero de 2005): 180–86. http://dx.doi.org/10.1177/0361198105190800122.

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To determine the major event pathways that result in sport utility vehicle (SUV) rollover, researchers at the University of Michigan Transportation Research Institute examined SUV rollover cases selected from the National Automotive Sampling System crashworthiness data system files for 1999 to 2001. Selected SUVs included the Ford Explorer, Jeep Cherokee, Chevrolet Blazer, Toyota 4-Runner, and GMC Jimmy for model years 1989 to 2001. Researchers coded up to six pre-rollover events, along with the stability of the vehicle (tracking or skidding) after each event. In addition, crash avoidance and recovery maneuvers were recorded, along with the rollover initiation type, location of rollover initiation, direction of roll, number of quarter turns of roll, location of roll, and surface condition at rollover initiation. Approximately 34% of SUV rollovers began with a loss of control caused by tire saturation, and about 75% of the loss-of-control cases were on icy, wet, or snowy roads. Of the SUVs that ran off the road as the first event, 47% returned to the road before rolling over, and of these, 76% were tracking (presumed under control) before initial road departure. Between 40% and 49% of SUV rollover crashes experienced yaw instability while still on the roadway before roll. These rollovers may be addressed by electronic stability control devices if such devices can increase the control limits of the vehicle.

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22

Döscher, R. y T. Koenigk. "Arctic rapid sea ice loss events in regional coupled climate scenario experiments". Ocean Science 9, n.º 2 (5 de marzo de 2013): 217–48. http://dx.doi.org/10.5194/os-9-217-2013.

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Abstract. Rapid sea ice loss events (RILEs) in a mini-ensemble of regional Arctic coupled climate model scenario experiments are analyzed. Mechanisms of sudden ice loss are strongly related to atmospheric circulation conditions and preconditioning by sea ice thinning during the seasons and years before the event. Clustering of events in time suggests a strong control by large-scale atmospheric circulation. Anomalous atmospheric circulation is providing warm air anomalies of up to 5 K and is forcing ice flow, affecting winter ice growth. Even without a seasonal preconditioning during winter, ice drop events can be initiated by anomalous inflow of warm air during summer. It is shown that RILEs can be generated based on atmospheric circulation changes as a major driving force without major competing mechanisms, other than occasional longwave effects during spring and summer. Other anomalous seasonal radiative forcing or short-lived forcers (e.g., soot) play minor roles or no role at all in our model. RILEs initiated by ocean forcing do not occur in the model, although cannot be ruled out due to model limitations. Mechanisms found are qualitatively in line with observations of the 2007 RILE.

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23

Savoia, Mariângela Gentil y Márcio Bernik. "Adverse life events and coping skills in panic disorder". Revista do Hospital das Clínicas 59, n.º 6 (2004): 337–40. http://dx.doi.org/10.1590/s0041-87812004000600005.

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Research literature and clinical experience shows that panic patients are often able to identify stressors that preceded the onset of their first attacks. In this study we investigated the relation between life events, coping skills, and panic disorder. METHODS: Forty-tree panic patients were compared with 29 control subjects regarding the occurrence and the impact of stressful life events in a 1-year period preceding the onset of panic attacks using the Social Readjustment Rating Scale and London Life Event and Difficulty Schedule. Coping skills were measured using the Ways of Coping Questionnaire. RESULTS: No differences were observed between panic patients and controls regarding the number of reported stressful life events in the previous year. Panic patients compared to controls reported loss of social support as the most meaningful class of events significantly more often. In response to stressful situations, panic patients more often used coping skills judged as ineffective. CONCLUSIONS: The present study suggests that the type of life event and the coping skills used in response to them, more than the occurrence of stressful events itself, may be associated with the onset of panic disorder.

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Rohith, G. "An investigation into aircraft loss of control and recovery solutions". Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 233, n.º 12 (25 de enero de 2019): 4509–22. http://dx.doi.org/10.1177/0954410019825942.

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Aircraft loss of control is an acute phenomenon that has far reaching consequences irrespective of the class and type of aircraft. In order to ensure safe aircraft operation, loss of control problem has to be addressed efficaciously. This paper investigates various factors that trigger the onset of loss of control events and recovery solutions for the same. Rather than relying on statistics alone, this paper concentrates on simulation-based investigation towards various loss of control scenarios and subsequent recovery schemes. Through bifurcation analysis, distinct abnormal dynamics have been identified and their contributions in driving the aircraft towards loss of control have been examined. The effect of steady wind on aircraft dynamics and the evolution of chaotic dynamics as a precursor to loss of control are presented. Aircraft loss of control under actuator impairment conditions are also probed into. Various loss of control recovery schemes have been investigated and a robust loss of control recovery solution based on sliding mode control is also presented.

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Rabie, Tamer, David Varga-Szabo, Markus Bender, Rastislav Pozgaj, Francois Lanza, Takashi Saito, Stephen P. Watson y Bernhard Nieswandt. "Diverging signaling events control the pathway of GPVI down-regulation in vivo". Blood 110, n.º 2 (15 de julio de 2007): 529–35. http://dx.doi.org/10.1182/blood-2006-11-058107.

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Abstract Coronary artery thrombosis is often initiated by platelet activation on collagen-rich subendothelial layers in the disrupted atherosclerotic plaque. The activating platelet collagen receptor glycoprotein VI (GPVI) noncovalently associates with the Fc receptor γ-chain (FcRγ), which signals through its immunoreceptor-tyrosine–based activation motif (ITAM) via the adaptor LAT leading to the activation of phospholipase Cγ2 (PLCγ2). GPVI is a promising antithrombotic target as anti-GPVI antibodies induce the irreversible loss of the receptor from circulating platelets by yet undefined mechanisms in humans and mice and long-term antithrombotic protection in the latter. However, the treatment is associated with transient but severe thrombocytopenia and reduced platelet reactivity to thrombin questioning its clinical usefulness. Here we show that GPVI down-regulation occurs through 2 distinct pathways, namely ectodomain shedding or internalization/intracellular clearing, and that both processes are abrogated in mice carrying a point mutation in the FcRγ-associated ITAM. In mice lacking LAT or PLCγ2, GPVI shedding is abolished, but the receptor is irreversibly down-regulated through internalization/intracellular clearing. This route of GPVI loss is not associated with thrombocytopenia or altered thrombin responses. These results reveal the existence of 2 distinct signaling pathways downstream of the FcRγ-ITAM and show that it is possible to uncouple GPVI down-regulation from undesired side effects with obvious therapeutic implications.

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Carman, Allan B., Sarah Gillespie, Kathryn Jones, Jessie Mackay, Gena Wallis y Stephan Milosavljevic. "All terrain vehicle loss of control events in agriculture: Contribution of pitch, roll and velocity". Ergonomics 53, n.º 1 (enero de 2010): 18–29. http://dx.doi.org/10.1080/00140130903380919.

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Silverman, Wendy K., Allen C. Israel y Linda S. Shapiro. "The suppressor effects of life events on locus of control as a predictor of weight loss". International Journal of Eating Disorders 5, n.º 2 (febrero de 1986): 371–75. http://dx.doi.org/10.1002/1098-108x(198602)5:2<371::aid-eat2260050216>3.0.co;2-9.

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Chotiwat, Christina y Ruth B. S. Harris. "Antagonism of specific corticotropin-releasing factor receptor subtypes selectively modifies weight loss in restrained rats". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 295, n.º 6 (diciembre de 2008): R1762—R1773. http://dx.doi.org/10.1152/ajpregu.00196.2008.

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Rats exposed to 3 h of restraint stress on each of 3 days (RRS) lose weight on the days of RRS and gain weight at the same rate as controls after stress ends, but do not return to the weight of controls. RRS rats also show an exaggerated endocrine response to subsequent novel stressors. Studies described here tested the effects of corticotropin-releasing factor receptor (CRFR) antagonism on RRS-induced weight loss, hypophagia, and corticosterone release during mild stress in the postrestraint period. Weight loss was not prevented by either peripheral or third-ventricle administration of a CRFR1 antagonist, antalarmin, before each restraint. Antalarmin did, however, allow recovery of body weight in the poststress period. Third-ventricle administration of a CRFR2 antagonist, antisauvagine 30, had no effect in RRS rats but caused sustained weight loss in control animals. Surprisingly, third-ventricle administration of the nonselective CRFR antagonist, astressin, caused hypophagia and reversible weight loss in control rats. It had no effect in RRS rats. None of the antagonists modified the corticosterone response to RRS or to mild stress in the post-RRS period, but antalarmin suppressed corticosterone during the period of restraint in Control rats. These results suggest that CRFR1 activation is required for the initiation of events that lead to a prolonged down-regulation of body weight in RRS rats. The sustained reduction in body weight is independent of the severity of hypophagia on the days of restraint and of RRS-induced corticosterone release.

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B. Mulcahy, Mark. "Room for improvement: the impact of bad losses on board quality". Journal of Applied Accounting Research 15, n.º 3 (4 de noviembre de 2014): 255–72. http://dx.doi.org/10.1108/jaar-10-2013-0081.

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Purpose – The purpose of this paper is to study the relationship between reporting a loss and changes in board quality. Low quality corporate governance is associated with adverse accounting outcomes and is characterised by the lack of non-executive and independent directors on the board. Changes in these board quality indicators in response to the reporting of a loss and conditioned by the severity of the loss are examined. Design/methodology/approach – This study uses four years of board information spanning the report of an initial loss for companies listed on the UK stock exchange. An industry and size matched control sample is used in a difference-in-difference analysis to isolate the impact of the loss from underlying changes in board quality. Findings – Overall the results indicate that more severe initial loss events precipitate improvements in board quality over and above the control sample as well as less severe loss events. Research limitations/implications – Although unambiguous, the reporting of a loss is only one measure of underperformance. Also the board quality indicators used in this study are two from several individual corporate governance variables and amalgamations used in the extent literature. Practical implications – The findings demonstrate that the relationship between corporate governance and performance is endogenous and that the majority of any improvement in board quality actually anticipates the reporting of the loss. Any celebration of improvements in governance need to be tempered by an understanding of the precariousness of the firms at which these improvements are made. Originality/value – This study contributes to a research stream that examines negative shocks, and losses in particular, as an event likely to precipitate firm-level changes in board quality, i.e. firms tend not to make improvements to board quality without the impetus to do so.

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Wang, Jing Chun, Jing Jing Liu y Wei Hong Hou. "Risk Assessment Based on Fuzzy Fault Tree for Waterproofing Accidents in Deep Excavation". Advanced Materials Research 739 (agosto de 2013): 732–36. http://dx.doi.org/10.4028/www.scientific.net/amr.739.732.

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In recent years accidents in deep excavation have frequently occurred, which brought a heavy loss in lives and property. The past cases of accident indicated water was a key one of accident resource. In this paper, water-control and its influencing factors in deep excavation were researched from sealing, draining and dewatering, and then fault tree of waterproofing was set up. The probability of waterproofing failure was calculated using Fuzzy Mathematics, and importance degrees for basic events were analyzed to find the events which would lead to the occurrence of the top event. The analysis can be used to make safety measures.

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Grandone, Elvira, Maurizio Margaglione, Donatella Colaizzo, Marina d'Addedda, Giuseppe Cappucci, Gennaro Vecchione, Natale Sciannamé, G. Pavone y G. Di Minno. "Factor V Leiden Is Associated with Repeated and Recurrent Unexplained Fetal Losses". Thrombosis and Haemostasis 77, n.º 05 (1997): 0822–24. http://dx.doi.org/10.1055/s-0038-1656060.

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SummaryActivated protein C resistance (APCR) is responsible for most cases of familial thrombosis. The factor V missense mutation Arg506>Gln (FV Leiden) has been recognized as the commonest cause of this condition. Recently, it has been suggested that APCR is associated with second trimester fetal loss. We investigated the distribution of FV Leiden in a sample (n = 43) of Caucasian women with a history of two or more unexplained fetal losses. A group (n = 118) of parous women with uneventful pregnancies from the same ethnical background served as control. We found the mutation in 7 cases (16.28%) and 5 controls (4.24%; p = 0.011). A statistically significant difference between women with only early fetal loss vs those with late events (p = 0.04) was observed. Our data demonstrate a strong association between FV Leiden and fetal loss. Furthermore, they indicate that late events are more common in these patients.

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32

Reichel, Franz, Christoph Peter, Volker Ewerbeck y Marcus Egermann. "Reducing Blood Loss in Revision Total Hip and Knee Arthroplasty: Tranexamic Acid Is Effective in Aseptic Revisions and in Second-Stage Reimplantations for Periprosthetic Infection". BioMed Research International 2018 (15 de noviembre de 2018): 1–9. http://dx.doi.org/10.1155/2018/3891870.

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Introduction. The aim of the study was to determine the usefulness of tranexamic acid (TXA) in revision total hip arthroplasty (rTHA) and revision total knee arthroplasty (rTKA). We analyzed the perioperative blood loss with and without TXA in aseptic rTHA and rTKA as well as in second-stage reimplantation for hip and knee periprosthetic infection. Materials and Methods. In this prospective cohort study, 147 patients receiving TXA (96 rTHA, 51 rTKA) were compared to a retrospective cohort of 155 patients without TXA (103 rTHA, 52 rTKA). The TXA regimen consisted of a preoperative bolus of 10 mg/kg bodyweight (BW) TXA plus 1 mg/kgBW/h perioperatively. Given blood products were documented and the perioperative blood loss was calculated. Thromboembolic events were registered until three months postoperatively. In subgroups, the effects of TXA were separately analyzed in 215 aseptic revisions as well as in 87 reimplantations in two-stage revisions for periprosthetic infection. Results. Both TXA groups showed a significantly reduced mean blood loss compared to the respective control groups. The TXA group of rTHA patients had a mean blood loss of 2916 ml ± 1226 ml versus 3611 ml ± 1474 ml in the control group (p<.001). For the TXA group of rTKA patients, mean calculated blood loss was 2756 ml ± 975 ml compared to 3441 ml ± 1100 ml in the control group (p=.0012). A significantly reduced blood loss was also found in the TXA subgroups for aseptic and septic revision procedures. No thromboembolic events were recorded among the TXA groups. Conclusions. There is a significant reduction of perioperative blood loss under TXA influence without an increased incidence of adverse events. The standard use of TXA can be recommended in aseptic hip and knee revision arthroplasties as well as in second-stage reimplantations for periprosthetic infection.

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Usher, Jane y Ursula Bond. "Recombination between Homoeologous Chromosomes of Lager Yeasts Leads to Loss of Function of the Hybrid GPH1 Gene". Applied and Environmental Microbiology 75, n.º 13 (8 de mayo de 2009): 4573–79. http://dx.doi.org/10.1128/aem.00351-09.

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ABSTRACT Yeasts used in the production of lagers contain complex allopolyploid genomes, resulting from the fusion of two different yeast species closely related to Saccharomyces cerevisiae and Saccharomyces bayanus. Recombination between the homoeologous chromosomes has generated a number of hybrid chromosomes. These recombination events provide potential for adaptive evolution through the loss or gain of gene function. We have examined the genotypic and phenotypic effects of one of the conserved recombination events that occurred on chromosome XVI in the region of YPR159W and YPR160W. Our analysis shows that the recombination event occurred within the YPR160W gene, which encodes the enzyme glycogen phosphorylase and generates a hybrid gene that does not produce mature mRNA and is nonfunctional due to frameshifts in the coding region. The loss of function of the hybrid gene leads to glycogen levels similar to those found in haploid yeast strains. The implications for the control of glycogen levels in fermentative yeasts are discussed.

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Oliveira, Vinicius S. L., Felipe G. Cabral y Marcos V. Moreira. "K-Loss Robust Diagnosability of Discrete-Event Systems". IFAC-PapersOnLine 53, n.º 4 (2020): 250–55. http://dx.doi.org/10.1016/j.ifacol.2021.04.064.

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35

Zhang, Pengfei y Samuel T. Ariaratnam. "Meta-Analysis of Storm Water Impacts in Urbanized Cities Including Runoff Control and Mitigation Strategies". Journal of Sustainable Development 11, n.º 6 (29 de noviembre de 2018): 27. http://dx.doi.org/10.5539/jsd.v11n6p27.

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The rate of urbanization has been impacted by global economic growth. A strong economy results in more people moving to already crowded urban centers to take advantage of increased employment opportunities often resulting in sprawling of the urban area. More natural land resources are being exploited to accommodate these anthropogenic activities. Subsequently, numerous natural land resources such as green areas or porous soil, which are less flood-prone and more permeable are being converted into buildings, parking lots, roads and underground utilities that are less permeable to storm water runoff from rain events. With the diminishing of the natural landscape that can drain storm water during a rainfall event, urban underground drainage systems are being designed and built to tackle the excess runoff resulting from urbanization. However, the rapid pace of urbanization has profoundly affected the formation of urban runoff thus resulting in the existing underground drainage system being unable to handle current flow conditions. This paper discusses storm water impacts in urbanized areas globally by reviewing historical storm water events and mitigation strategies accompanied with runoff reduction performance that are considered simultaneously for the purpose of relieving the stress on underground drainage systems. It was found that the stormwater impact on ten selected typical urban areas were enormously destructive followed by billions of direct economy loss, fatalities, damaged properties and residents’ relocations. Furthermore, the meta-analysis of selected six runoff mitigation methods indicated that the average runoff reduction percent ranged from 43% to 61% under different rain events in various installed sites across different event years.

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Tan, C. S., C. F. Drury, J. D. Gaynor y T. W. Welacky. "Integrated Soil, Crop and Water Management System to Abate Herbicide and Nitrate Contamination of the Great Lakes". Water Science and Technology 28, n.º 3-5 (1 de agosto de 1993): 497–507. http://dx.doi.org/10.2166/wst.1993.0453.

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Corn management practices, incorporating annual ryegrass intercrop, conservation tillage and water table management, were evaluated to reduce herbicide and N0−3 losses through surface runoff and tile drainage. The integrated management system being developed at Harrow in S.W. Ontario reduced herbicide input 50% by banding the chemical over the seed row. Runoff events close to herbicide application contained high concentrations of atrazine, metribuzin and metolachlor. However, the volume of runoff was low during the 1991 growing season, therefore herbicide loss was low (<2% of applied). The three herbicides rapidly dissipated in the soil so that subsequent runoff events transported little herbicide in the runoff water. The total quantity of de-ethyl atrazine loss was lower from soil saver than moldboard plow. No water table control or intercrop effects were found in 1991 for herbicide loss because of the drought Tile drainage resulted in a greater volume of water and loss of N0−3 than with surface runoff. Consequently, over 97% of the total N0−3 loss occurred through tile drainage. The flow weighted N0−3 concentration in tile drainage water was 22.5 mg N L−1 for the drainage treatments and 15.1 mg N L−1 for the water table control treatments from Nov. 1, 1991 till April 30, 1992. During this time period, N0−3 loss through tile drainage was 57.8 kg N ha−1 from the drainage treatments and 36.3 kg N ha−1 from the water table control treatments. Therefore, the water table control treatment reduced the flow weighted N0−3 concentration in tile drainage water by 33% and total N0−3 loss by 37%. The water table control treatments combined with soil saver tillage resulted in lower concentrations and losses of N0−3 than with any other treatments.

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Attiyeh, E. F., Y. P. Mosse, S. Diskin, C. Hou, M. A. Attiyeh, D. Baker, D. Strother, M. Schmidt, W. B. London y J. M. Maris. "Identification of genomic DNA signatures predicting relapse in low- and intermediate-risk neuroblastoma using a case control design and high-density SNP genotyping: A Children's Oncology Group (COG) study". Journal of Clinical Oncology 25, n.º 18_suppl (20 de junio de 2007): 9500. http://dx.doi.org/10.1200/jco.2007.25.18_suppl.9500.

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9500 Background: Neuroblastoma (NB) is a childhood malignancy with a heterogeneous clinical course. Clinical and genomic markers are powerful predictors of outcome and are used to stratify cases for treatment intensity, but imprecision remains. Methods: We identified all disease recurrences from the recently closed COG low- (P9641: 903 eligible, 63 events) and intermediate-risk (A3961: 467 eligible, 40 events) NB phase III trials. To date, tumor DNA from 35 cases and 90 controls (P9641/A3961 patients without event) was used for whole genome copy number and genotype evaluation on the Illumina HumanHap550 (550K SNPs) array. An in-house algorithm was developed to assign genomic copy number and loss of heterozygosity based on probe intensity (log R ratio) and degree of allelic imbalance (B allele frequency). Results: A total of 988 chromosomal aberrations were identified; 231 (23.4%) were whole chromosome (WC) copy number aberrations (CNA). Unsupervised hierarchical clustering identified 10 tumor subsets, with 2 highly enriched with cases showing progression events (13/21; 61%), and 2 dominated by WC gains (chromosomes 2, 6, 7 and 18) with only 2/20 events. Regional aberrations most highly associated with EFS included loss of 11q14-qter (p=0.036), and gain of 11p (p=0.003), 11q13 (p=0.020), and 17q23-qter (p=0.005). Other regional CNAs at borderline univariate significance for EFS included partial gain at 2p, 2q, 6q, 7q, 12q and 13q. The pattern 11p and proximal 11q gain associated with loss of distal 11q was associated with relapse and death (p=0.006 and p=0.023). Conclusion: Whole genome SNP genotyping detects patterns of chromosomal CNAs predictive of EFS, even in situations where events are rare such as low- and intermediate- risk NB. These data support chromosomal 11 and 17 structural CNAs as being most highly predictive of relapse in otherwise favorable NBs, but also suggest that other CNAs likely cooperate and may improve precisions for risk prediction. These data can be used to identify patients eligible for chemotherapy reduction/elimination, and perhaps others for intensification. Ongoing analyses of the remaining samples will extend these conclusions. No significant financial relationships to disclose.

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Newcomb, Michael D. y L. L. Harlow. "Life events and substance use among adolescents: Mediating effects of perceived loss of control and meaninglessness in life." Journal of Personality and Social Psychology 51, n.º 3 (1986): 564–77. http://dx.doi.org/10.1037/0022-3514.51.3.564.

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Tang, Feng, Ping Zhang y Fang Li. "The Fuzzy Feedback Scheduling of Real-Time Middleware in Cyber-Physical Systems for Robot Control". Journal of Sensors 2016 (2016): 1–10. http://dx.doi.org/10.1155/2016/3251632.

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Cyber-physical systems for robot control integrate the computing units and physical devices, which are real-time systems with periodic events. This work focuses on CPS task scheduling in order to solve the problem of slow response and packet loss caused by the interaction between each service. The two-level fuzzy feedback scheduling scheme is designed to adjust the task priority and period according to the combined effects of the response time and packet loss. Empirical results verify the rationality of the cyber-physical system architecture for robot control and illustrate the feasibility of the fuzzy feedback scheduling method.

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Chien, Hsiang-Wen, Pei-Hsuan Wu, Kai Wang, Chi-Chin Sun, Jing-Yang Huang, Shun-Fa Yang, Hung-Chi Chen y Chia-Yi Lee. "Increased Incidence of Glaucoma in Sensorineural Hearing Loss: A Population-Based Cohort Study". International Journal of Environmental Research and Public Health 16, n.º 16 (14 de agosto de 2019): 2907. http://dx.doi.org/10.3390/ijerph16162907.

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The purpose of the current study was to evaluate the incidence of glaucoma in patients diagnosed with sensorineural hearing loss (SNHL) via the application of the National Health Insurance Research Database in Taiwan. A retrospective cohort study was conducted. Patients with a diagnosis of SNHL were enrolled in the study group after an exclusion procedure and a propensity score matched group without SNHL was served as the control group with a 1:2 ratio. The main outcome was regarded as the emergence of glaucoma diagnostic codes. Cox proportional hazard regression was applied to analyze the incidence and adjusted hazard ratio (aHR) of glaucoma in the multivariate model. A total of 15,686 patients diagnosed with SNHL were enrolled in the study group while another 31,372 non-SNHL individuals served as the control group. There were 444 glaucoma events in the study group and 647 glaucoma events in those non-SNHL individuals after the follow-up interval of 16 years. The study group demonstrated a significantly higher aHR compared to the control group after adjusting for multiple possible risk factors. In the subgroup analysis, both the normal tension glaucoma and angle closure glaucoma subgroups revealed a higher aHR in the study group. In conclusion, the patients with SNHL demonstrated a higher incidence of developing glaucoma. Moreover, the incidence was more prominent for patients diagnosed with normal tension glaucoma and angle closure glaucoma.

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Lee, Alexandra K., Mark Woodward, Dan Wang, Toshiaki Ohkuma, Bethany Warren, A. Richey Sharrett, Bryan Williams et al. "The Risks of Cardiovascular Disease and Mortality Following Weight Change in Adults with Diabetes: Results from ADVANCE". Journal of Clinical Endocrinology & Metabolism 105, n.º 1 (7 de octubre de 2019): 152–62. http://dx.doi.org/10.1210/clinem/dgz045.

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Abstract Context Weight loss is strongly recommended for overweight and obese adults with type 2 diabetes. Unintentional weight loss is associated with increased risk of all-cause mortality, but few studies have examined its association with cardiovascular outcomes in patients with diabetes. Objective To evaluate 2-year weight change and subsequent risk of cardiovascular events and mortality in established type 2 diabetes. Design and Setting The Action in Diabetes and Vascular Disease: Preterax and Diamicron-MR Controlled Evaluation was an international, multisite 2×2 factorial trial of intensive glucose control and blood pressure control. We examined 5 categories of 2-year weight change: >10% loss, 4% to 10% loss, stable (±<4%), 4% to 10% gain, and >10% gain. We used Cox regression with follow-up time starting at 2 years, adjusting for intervention arm, demographics, cardiovascular risk factors, and diabetes medication use from the 2-year visit. Results Among 10 081 participants with valid weight measurements, average age was 66 years. By the 2-year examination, 4.3% had >10% weight loss, 18.4% had 4% to 10% weight loss, and 5.3% had >10% weight gain. Over the following 3 years of the trial, >10% weight loss was strongly associated with major macrovascular events (hazard ratio [HR], 1.75; 95% confidence interval [CI], 1.26-2.44), cardiovascular mortality (HR, 2.76; 95% CI, 1.87-4.09), all-cause mortality (HR, 2.79; 95% CI, 2.10-3.71), but not major microvascular events (HR, 0.91; 95% CI, 0.61-1.36), compared with stable weight. There was no evidence of effect modification by baseline body mass index, age, or type of diabetes medication. Conclusions In the absence of substantial lifestyle changes, weight loss may be a warning sign of poor health meriting further workup in patients with type 2 diabetes.

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Cofelice, Martina, Francesco Lopez y Francesca Cuomo. "Quality Control of Fresh-Cut Apples after Coating Application". Foods 8, n.º 6 (1 de junio de 2019): 189. http://dx.doi.org/10.3390/foods8060189.

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The growing demand for ready-to-eat fresh fruits has led to set-up appropriate strategies for preserving fruit quality and freshness of such commodities. To slow down the deterioration events such as respiration, moisture loss and enzymatic activity, ready-to-eat products should be protected with an edible film. A suitable coating should combine hydrophilic and hydrophobic features to ensure good mechanical and gas barrier properties. Alginate/essential oil nanoformulations, one with low and the other with high oil content, here proposed to protect apple pieces during storage, were first characterized through dynamic light scattering and rheology. The effect of the application of the nanoformulations on the quality parameters of apples stored at 4 °C was considered by evaluating weight loss, pH and titratable acidity, total phenols content and the fruit appearance during storage. Mainly on the basis of pH and titratable acididty variation, the nanoformulation with low oil content resulted eligible for preserving the quality of fresh-cut apple pieces during storage.

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Baskaran, Dinnish, Syed Rahman, Yousuf Salmasi, Saied Froghi, Onur Berber y Marc George. "Effect of tranexamic acid use on blood loss and thromboembolic risk in hip fracture surgery: systematic review and meta-analysis". HIP International 28, n.º 1 (10 de abril de 2017): 3–10. http://dx.doi.org/10.5301/hipint.5000556.

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Introduction: Intravenous tranexamic acid (IV TXA) is a recognised pharmaceutical intervention utilised to minimise blood loss and allogenic blood transfusion. However, the use of IV TXA in hip fracture surgery remains inconclusive. We conducted a meta-analysis to investigate the role of TXA in operative hip fracture management on operative and total blood loss, allogenic blood transfusion requirements and impact on venous thromboembolic (VTE) event incidence. Methods: A systematic computerised literature search of PubMed, Medline, Embase, Ovid, The Cochrane Controlled Trials Register, Trip and Google was conducted. We reviewed the efficacy of IV TXA on perioperative blood loss, total blood loss, pre- and postoperative haemoglobin differences, duration of surgery, allogenic blood transfusion requirements and VTE events. Results: 8 studies were eligible including 6 randomised control trials and 2 cohort studies. Patients receiving IV TXA had reduced mean total blood loss of 442.9 mls (95% CI, 426.5-459.3; p<0.00001), reduced operative blood loss of 88.5 mls (95% CI, 59.9-117.2; p<0.00001), a decrease in the need for allogenic blood transfusion (OR 0.37; 95% CI, 0.26-0.53; p<0.00001) and a reduction in pre- and postoperative haemoglobin difference (p = 0.013.) There was no significant increase in VTE risk (OR 1.59; 95% CI 0.67-3.75; p>0.29) or significant difference on duration of surgery seen with IV TXA usage (p>0.06). Conclusions: Our review demonstrated the efficacy of IV TXA in minimising perioperative, reducing total blood loss and lowering the necessity for allogenic blood transfusions with no significant increased risk in VTE events.

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Hoppe, David, Stefan Helfmann y Constantin A. Rothkopf. "Humans quickly learn to blink strategically in response to environmental task demands". Proceedings of the National Academy of Sciences 115, n.º 9 (14 de febrero de 2018): 2246–51. http://dx.doi.org/10.1073/pnas.1714220115.

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Eye blinking is one of the most frequent human actions. The control of blinking is thought to reflect complex interactions between maintaining clear and healthy vision and influences tied to central dopaminergic functions including cognitive states, psychological factors, and medical conditions. The most imminent consequence of blinking is a temporary loss of vision. Minimizing this loss of information is a prominent explanation for changes in blink rates and temporarily suppressed blinks, but quantifying this loss is difficult, as environmental regularities are usually complex and unknown. Here we used a controlled detection experiment with parametrically generated event statistics to investigate human blinking control. Subjects were able to learn environmental regularities and adapted their blinking behavior strategically to better detect future events. Crucially, our design enabled us to develop a computational model that allows quantifying the consequence of blinking in terms of task performance. The model formalizes ideas from active perception by describing blinking in terms of optimal control in trading off intrinsic costs for blink suppression with task-related costs for missing an event under perceptual uncertainty. Remarkably, this model not only is sufficient to reproduce key characteristics of the observed blinking behavior such as blink suppression and blink compensation but also predicts without further assumptions the well-known and diverse distributions of time intervals between blinks, for which an explanation has long been elusive.

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Pernik, Mark N., Luke J. Dosselman, Salah G. Aoun, Adrienne D. Walker, Kristen Hall, Valery Peinado Reyes, David L. McDonagh y Carlos A. Bagley. "The effectiveness of tranexamic acid on operative and perioperative blood loss in long-segment spinal fusions: a consecutive series of 119 primary procedures". Journal of Neurosurgery: Spine 32, n.º 5 (mayo de 2020): 768–74. http://dx.doi.org/10.3171/2019.11.spine191174.

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OBJECTIVEThe aim of this study was to determine if the use of tranexamic acid (TXA) in long-segment spinal fusion surgery can help reduce perioperative blood loss, transfusion requirements, and morbidity.METHODSIn this retrospective single-center study, the authors included 119 consecutive patients who underwent thoracolumbar fusion spanning at least 4 spinal levels from October 2016 to February 2019. Blood loss, transfusion requirements, perioperative morbidity, and adverse thrombotic events were compared between a cohort receiving intravenous TXA and a control group that did not.RESULTSThere was no significant difference in any measure of intraoperative blood loss (1514.3 vs 1209.1 mL, p = 0.29) or transfusion requirement volume between the TXA and control groups despite a higher number of pelvic fusion procedures in the TXA group (85.9% vs 62.5%, p = 0.003). Postoperative transfusion volume was significantly lower in TXA patients (954 vs 572 mL, p = 0.01). There was no difference in the incidence of thrombotic complications between the groups.CONCLUSIONSTXA appears to provide a protective effect against blood loss in long-segment spine fusion surgery specifically when pelvic dissection and fixation is performed. TXA also seems to decrease postoperative transfusion requirements without increasing the risk of adverse thrombotic events.

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GILBERT, PAUL. "Evolution and depression: issues and implications". Psychological Medicine 36, n.º 3 (20 de octubre de 2005): 287–97. http://dx.doi.org/10.1017/s0033291705006112.

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Depression is well recognized to be rooted in the down-regulation of positive affect systems. This paper reviews some of the social and non-social theories that seek to explain the potential adaptive advantages of being able to tone down positive affect, and how dysfunctions in such affect control can occur in some contexts. Common to most evolutionary theories of depression is the view that loss of control over aversive events and/or major resources/rewards exert downward pressure on positive affect. Social theories, however, suggest that it is loss of control over the social environment that is particularly depressogenic. Two evolutionary theories (the attachment-loss, and the defeat-loss theories) are briefly reviewed and their interaction considered. It is suggested that phenotypes for toning down positive affect, in the face of loss of control, may become more severe in the context of socially hostile, unsupportive and/or excessively competitive environments. The paper briefly considers how human competencies for self-evaluation in relation to others, rumination, self-criticism, and modern social contexts can accentuate dysfunctional expressions of affect regulation.

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Hu, Yan, Xiaoting Chen, Xiaojing Chen, Shuang Zhang, Tianyan Jiang, Jing Chang y Yanhong Gao. "Bone Loss Prevention of Bisphosphonates in Patients with Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis". Canadian Journal of Gastroenterology and Hepatology 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/2736547.

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Objective. The purpose of this study was to evaluate the effect of bisphosphonates in improving bone mineral density (BMD) and decreasing the occurrence rate of fractures and adverse events in patients with inflammatory bowel disease (IBD). Methods. Randomized controlled trials (RCTs) which use bisphosphonates in IBD patients were identified in PubMed, MEDLINE database, EMBASE database, Web of Knowledge, and the Cochrane Databases between 1990 and June 2016. People received bisphosphonate or placebos with a follow-up of at least one year were also considered. STATA 12.0 software was used for the meta-analysis. Results. Eleven randomized clinical trials were included in the meta-analysis. The data indicated that the percentage change in the increased BMD in the bisphosphonates groups was superior to that of the control groups at the lumbar spine and total hip. At the femoral neck, there was no significant difference between the two groups. The incidence of new fractures during follow-up showed significant reduction. The adverse event analysis revealed no significant difference between the two groups. Conclusion. Our results demonstrate that bisphosphonates therapy has an effect on bone loss in patients with IBD but show no evident efficiency at increasing the incidence of adverse events.

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He, Bin, Yuanqiang Li, Shuai Xu, Yunsheng Ou y Jinqiu Zhao. "Tranexamic Acid for Blood Loss after Transforaminal Posterior Lumbar Interbody Fusion Surgery: A Double-Blind, Placebo-Controlled, Randomized Study". BioMed Research International 2020 (14 de agosto de 2020): 1–6. http://dx.doi.org/10.1155/2020/8516504.

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Background. Transforaminal lumbar interbody fusion (TLIF) may result in significant blood loss and an increase in blood transfusion. Though tranexamic acid (TXA) is widely studied for the hemostasis of arthroplasty, there is little information on the use of TXA for TLIF surgery. Methods. This prospective randomized, double-blind, placebo-controlled trial was conducted to study the influence of TXA (intravenous bolus of 10 mg/kg 15 minutes before skin incision followed by intravenous infusion of 6-8 mg/kg/h up to a total dose of 15 mg/kg during the surgery) on the blood loss and Enhanced Recovery After Surgery (ERAS) after TLIF surgery. 40 patients were randomized into two groups: TXA group (tranexamic acid) and control group (placebo). Baseline characteristics were comparable between the TXA group and the control group before the surgery. Outcomes assessed included blood loss, total postoperative drainage, time for drainage removal, time to ambulation, hospital stay after surgery, postoperative hemoglobin (Hb) one day after surgery, and adverse events. Results. Compared to patients in the control group after TLIF surgery, patients in the TXA group have significantly reduced intraoperative hemorrhage and time to ambulation after surgery but show similar hospital stay, postoperative drainage, time for drainage removal, postoperative Hb one day after surgery, and adverse events. Conclusions. TXA shows important ability in controlling blood loss and promoting the ERAS after TLIF surgery.

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Clay, Lynne, Gareth J. Treharne, E. Jean C. Hay-Smith y Stephan Milosavljevic. "Is workplace satisfaction associated with self-reported quad bike loss of control events among farm workers in New Zealand?" Applied Ergonomics 45, n.º 3 (mayo de 2014): 496–502. http://dx.doi.org/10.1016/j.apergo.2013.07.003.

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Moskal, Joseph y Susan Capps. "Intra-articular Tranexamic Acid in Primary Total Knee Arthroplasty: Meta-analysis". Journal of Knee Surgery 31, n.º 01 (10 de abril de 2017): 056–67. http://dx.doi.org/10.1055/s-0037-1600092.

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AbstractTotal knee arthroplasty (TKA) is associated with an increased need for blood transfusions and thus an increase in risks associated with blood transfusion such as transfusion reactions, infections, fluid overload, and altered mental status. Tranexamic acid (TXA) is an antifibrinolytic medication that can reduce perioperative blood loss in TKA. However, the best method of delivery has not been defined although topical intra-articular TXA (IA-TXA) may have a theoretical advantage as it is applied directly when and where it is needed to control bleeding. Blinded and nonblinded randomized controlled trials and case-controlled trials published since 2010 were found using database searches. Data were extracted and analyzed with the goal of discovering through meta-analysis if IA-TXA reduces blood loss, blood transfusions, and without increasing adverse events, especially thromboembolic events, compared with placebo. Blood loss from suction drains and calculated total blood loss were significantly lower in the IA-TXA group. The frequency of blood transfusion and the number of units of blood transfused were significantly lower in the IA-TXA group. The risk of adverse events was not increased for IA-TXA versus placebo. Topical IA-TXA in primary, unilateral TKA successfully reduces blood loss and the frequency of blood transfusions. In addition, it does not appear to increase the risk of thromboembolic adverse events. There is need for further research to determine the optimal dosage and the preferred delivery system of IA-TXA in TKA.

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