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Sample records for failure patterns caused

  1. Using pattern analysis methods to do fast detection of manufacturing pattern failures

    NASA Astrophysics Data System (ADS)

    Zhao, Evan; Wang, Jessie; Sun, Mason; Wang, Jeff; Zhang, Yifan; Sweis, Jason; Lai, Ya-Chieh; Ding, Hua

    2016-03-01

    At the advanced technology node, logic design has become extremely complex and is getting more challenging as the pattern geometry size decreases. The small sizes of layout patterns are becoming very sensitive to process variations. Meanwhile, the high pressure of yield ramp is always there due to time-to-market competition. The company that achieves patterning maturity earlier than others will have a great advantage and a better chance to realize maximum profit margins. For debugging silicon failures, DFT diagnostics can identify which nets or cells caused the yield loss. But normally, a long time period is needed with many resources to identify which failures are due to one common layout pattern or structure. This paper will present a new yield diagnostic flow, based on preliminary EFA results, to show how pattern analysis can more efficiently detect pattern related systematic defects. Increased visibility on design pattern related failures also allows more precise yield loss estimation.

  2. Time-related patterns of ventricular shunt failure.

    PubMed

    Kast, J; Duong, D; Nowzari, F; Chadduck, W M; Schiff, S J

    1994-11-01

    Proximal obstruction is reported to be the most common cause of ventriculoperitoneal (VP) shunt failure, suggesting that imperfect ventricular catheter placement and inadequate valve mechanisms are major causes. This study retrospectively examined patterns of shunt failure in 128 consecutive patients with symptoms of shunt malfunction over a 2-year period. Factors analyzed included site of failure, time from shunt placement or last revision to failure, age of patient at time of failure, infections, and primary etiology of the hydrocephalus. One hundred of these patients required revisions; 14 revisions were due to infections. In this series there was a higher incidence of distal (43%) than of proximal (35%) failure. The difference was not statistically significant when the overall series was considered; however, when factoring time to failure as a variable, marked differences were noted regardless of the underlying cause of hydrocephalus or the age of the patient. Of the 49 patients needing a shunt revision or replacement within 2 years of the previous operation, 50% had proximal malfunction, 14% distal, and 10% had malfunctions attributable directly to the valve itself. Also, 12 of the 14 infections occurred during this time interval. In sharp contrast, of the 51 patients having shunt failure from 2 to more than 12 years after the previous procedure, 72% had distal malfunction, 21% proximal, and only 6% had a faulty valve or infection. This difference between time to failure for proximal versus distal failures was statistically significant (P < 0.00001 for both Student's t-test and non-parametric Mann-Whitney U-test).(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Common Cause Failure Modeling

    NASA Technical Reports Server (NTRS)

    Hark, Frank; Britton, Paul; Ring, Rob; Novack, Steven D.

    2016-01-01

    Common Cause Failures (CCFs) are a known and documented phenomenon that defeats system redundancy. CCFS are a set of dependent type of failures that can be caused by: system environments; manufacturing; transportation; storage; maintenance; and assembly, as examples. Since there are many factors that contribute to CCFs, the effects can be reduced, but they are difficult to eliminate entirely. Furthermore, failure databases sometimes fail to differentiate between independent and CCF (dependent) failure and data is limited, especially for launch vehicles. The Probabilistic Risk Assessment (PRA) of NASA's Safety and Mission Assurance Directorate at Marshal Space Flight Center (MFSC) is using generic data from the Nuclear Regulatory Commission's database of common cause failures at nuclear power plants to estimate CCF due to the lack of a more appropriate data source. There remains uncertainty in the actual magnitude of the common cause risk estimates for different systems at this stage of the design. Given the limited data about launch vehicle CCF and that launch vehicles are a highly redundant system by design, it is important to make design decisions to account for a range of values for independent and CCFs. When investigating the design of the one-out-of-two component redundant system for launch vehicles, a response surface was constructed to represent the impact of the independent failure rate versus a common cause beta factor effect on a system's failure probability. This presentation will define a CCF and review estimation calculations. It gives a summary of reduction methodologies and a review of examples of historical CCFs. Finally, it presents the response surface and discusses the results of the different CCFs on the reliability of a one-out-of-two system.

  4. Common Cause Failure Modeling

    NASA Technical Reports Server (NTRS)

    Hark, Frank; Britton, Paul; Ring, Rob; Novack, Steven D.

    2015-01-01

    Common Cause Failures (CCFs) are a known and documented phenomenon that defeats system redundancy. CCFS are a set of dependent type of failures that can be caused by: system environments; manufacturing; transportation; storage; maintenance; and assembly, as examples. Since there are many factors that contribute to CCFs, the effects can be reduced, but they are difficult to eliminate entirely. Furthermore, failure databases sometimes fail to differentiate between independent and CCF (dependent) failure and data is limited, especially for launch vehicles. The Probabilistic Risk Assessment (PRA) of NASA's Safety and Mission Assurance Directorate at Marshall Space Flight Center (MFSC) is using generic data from the Nuclear Regulatory Commission's database of common cause failures at nuclear power plants to estimate CCF due to the lack of a more appropriate data source. There remains uncertainty in the actual magnitude of the common cause risk estimates for different systems at this stage of the design. Given the limited data about launch vehicle CCF and that launch vehicles are a highly redundant system by design, it is important to make design decisions to account for a range of values for independent and CCFs. When investigating the design of the one-out-of-two component redundant system for launch vehicles, a response surface was constructed to represent the impact of the independent failure rate versus a common cause beta factor effect on a system's failure probability. This presentation will define a CCF and review estimation calculations. It gives a summary of reduction methodologies and a review of examples of historical CCFs. Finally, it presents the response surface and discusses the results of the different CCFs on the reliability of a one-out-of-two system.

  5. Common Cause Failures and Ultra Reliability

    NASA Technical Reports Server (NTRS)

    Jones, Harry W.

    2012-01-01

    A common cause failure occurs when several failures have the same origin. Common cause failures are either common event failures, where the cause is a single external event, or common mode failures, where two systems fail in the same way for the same reason. Common mode failures can occur at different times because of a design defect or a repeated external event. Common event failures reduce the reliability of on-line redundant systems but not of systems using off-line spare parts. Common mode failures reduce the dependability of systems using off-line spare parts and on-line redundancy.

  6. Common Cause Failure Modeling

    NASA Technical Reports Server (NTRS)

    Hark, Frank; Britton, Paul; Ring, Robert; Novack, Steven

    2015-01-01

    Space Launch System (SLS) Agenda: Objective; Key Definitions; Calculating Common Cause; Examples; Defense against Common Cause; Impact of varied Common Cause Failure (CCF) and abortability; Response Surface for various CCF Beta; Takeaways.

  7. Root Cause Failure Analysis of Stator Winding Insulation failure on 6.2 MW hydropower generator

    NASA Astrophysics Data System (ADS)

    Adhi Nugroho, Agus; Widihastuti, Ida; Ary, As

    2017-04-01

    Insulation failure on generator winding insulation occurred in the Wonogiri Hydropower plant has caused stator damage since ase was short circuited to ground. The fault has made the generator stop to operate. Wonogiri Hydropower plant is one of the hydroelectric plants run by PT. Indonesia Power UBP Mrica with capacity 2 × 6.2 MW. To prevent damage to occur again on hydropower generators, an analysis is carried out using Root Cause Failure Analysis RCFA is a systematic approach to identify the root cause of the main orbasic root cause of a problem or a condition that is not wanted. There are several aspects to concerned such as: loading pattern and operations, protection systems, generator insulation resistance, vibration, the cleanliness of the air and the ambient air. Insulation damage caused by gradual inhomogeneous cooling at the surface of winding may lead in to partial discharge. In homogeneous cooling may present due to lattice hampered by dust and oil deposits. To avoid repetitive defects and unwanted condition above, it is necessary to perform major maintenance overhaul every 5000-6000 hours of operation.

  8. Causes of corneal graft failure in India.

    PubMed

    Dandona, L; Naduvilath, T J; Janarthanan, M; Rao, G N

    1998-09-01

    The success of corneal grafting in visual rehabilitation of the corneal blind in India depends on survival of the grafts. Understanding the causes of graft failure may help reduce the risk of failure. We studied these causes in a series of 638 graft failures at our institution. Multivariate logistic regression analysis was used to evaluate the association of particular causes of graft failure with indications for grafting, socioeconomic status, age, sex, host corneal vascularization, donor corneal quality, and experience of surgeon. The major causes of graft failure were allograft rejection (29.2%), increased intraocular pressure (16.9%), infection excluding endophthalmitis (15.4%), and surface problems (12.7%). The odds of infection causing graft failure were significantly higher in patients of lower socioeconomic status (odds ratio 2.45, 95% CI 1.45-4.15). Surface problems as a cause of graft failure was significantly associated with grafts done for corneal scarring or for regrafts (odds ratio 3.36, 95% CI 1.80-6.30). Increased intraocular pressure as a cause of graft failure had significant association with grafts done for aphakic or pseudophakic bullous keratopathy, congenital conditions or glaucoma, or regrafts (odds ratio 2.19, 95% CI 1.25-3.84). Corneal dystrophy was the indication for grafting in 12 of the 13 cases of graft failure due to recurrence of host disease. Surface problems, increased intraocular pressure, and infection are modifiable risk factors that are more likely to cause graft failure in certain categories of patients in India. Knowledge about these associations can be helpful in looking for and aggressively treating these modifiable risk factors in the at-risk categories of corneal graft patients. This can possibly reduce the chance of graft failure.

  9. [Clinical patterns and stages of multiple organ failure in the elderly].

    PubMed

    Wang, S

    1990-05-01

    Multiple organ failure in the elderly (MOFE) is a new clinical syndrome different from multiple organ failure (MOF) caused by trauma occurring most often in young and mid-aged persons. The authors retrospectively analysed 158 cases of MOFE hospitalized in the past 12 years and commented on its definition, diagnostic criteria, clinical patterns and stages. The suggested definition of MOFE is the sequential 2 or more organs failure within a short period in the elderly patients (greater than or equal to 60 years old) with multiple organ chronic diseases in the presence of aging of organs and age-related malfunction. The most common precipitating factors are pulmonary infections and acute attack of chronic cardiac, cerebral and renal diseases. The interval between failures of various organs is mostly less than 10 days and seldom longer than 1 month. MOFE has 3 different patterns: rapid pattern with single phase; delayed pattern with two phases and recurrent pattern with multiple phase. In the last pattern the patients suffer from multiple attacks of multiple organ failure. It is only seen in MOFE, but not in MOF. The presentation of this particular pattern is related to the following facts: (1). A few organs or only the heart and lungs are involved. (2) Kidney, brain and hemopoietic system etc. usually with poor prognosis are not involved. (3) The age of patients are relatively younger. (4) More resuscitation experiences have been accumulated and better resuscitation measures are available. The clinical course of MOFE can be divided into 3 stages: prefailure stage (stage I), failure compensations stage (stage II) and decompensation stage (stage III).(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Common Cause Failure Modeling: Aerospace Versus Nuclear

    NASA Technical Reports Server (NTRS)

    Stott, James E.; Britton, Paul; Ring, Robert W.; Hark, Frank; Hatfield, G. Spencer

    2010-01-01

    Aggregate nuclear plant failure data is used to produce generic common-cause factors that are specifically for use in the common-cause failure models of NUREG/CR-5485. Furthermore, the models presented in NUREG/CR-5485 are specifically designed to incorporate two significantly distinct assumptions about the methods of surveillance testing from whence this aggregate failure data came. What are the implications of using these NUREG generic factors to model the common-cause failures of aerospace systems? Herein, the implications of using the NUREG generic factors in the modeling of aerospace systems are investigated in detail and strong recommendations for modeling the common-cause failures of aerospace systems are given.

  11. Common Cause Failure Modes

    NASA Technical Reports Server (NTRS)

    Wetherholt, Jon; Heimann, Timothy J.; Anderson, Brenda

    2011-01-01

    High technology industries with high failure costs commonly use redundancy as a means to reduce risk. Redundant systems, whether similar or dissimilar, are susceptible to Common Cause Failures (CCF). CCF is not always considered in the design effort and, therefore, can be a major threat to success. There are several aspects to CCF which must be understood to perform an analysis which will find hidden issues that may negate redundancy. This paper will provide definition, types, a list of possible causes and some examples of CCF. Requirements and designs from NASA projects will be used in the paper as examples.

  12. A huge bladder calculus causing acute renal failure.

    PubMed

    Komeya, Mitsuru; Sahoda, Tamami; Sugiura, Shinpei; Sawada, Takuto; Kitami, Kazuo

    2013-02-01

    A 81-year-old male was referred to our emergency outpatient unit due to acute renal failure. The level of serum creatinine was 276 μmol/l. A CT scan showed bilateral hydronephroureter, large bladder stone (7 cm × 6 cm × 6 cm) and bladder wall thickness. He was diagnosed as post renal failure due to bilateral hydronephroureter. Large bladder stone is thought to be the cause of bilateral hydronephroureter and renal failure. To improve renal failure, we performed open cystolithotomy and urethral catheterization. Three days after the surgery, the level of serum creatinine decreased to 224 μmol/l. He was discharged from our hospital with uneventful course. Bladder calculus is thought to be a rare cause of renal failure. We summarize the characteristics of bladder calculus causing renal failure. We should keep that long-term pyuria and urinary symptom, and repeated urinary tract infection can cause huge bladder calculus and renal failure in mind.

  13. High-Output Heart Failure Caused by Thyrotoxicosis and Beriberi.

    PubMed

    McCulloch, Brenda

    2015-12-01

    High-output heart failure is not seen as commonly as low-output heart failure and some of the typical guideline recommendations may not benefit patients with high-output failure. High-output failure is caused by several diseases, including thyrotoxicosis and beriberi, highlighted in this article. Thyrotoxicosis, caused by excessive thyroid hormone production, has profound hemodynamic effects. Wet beriberi, affecting predominately the cardiovascular system, is caused by severe thiamine deficiency, most commonly seen in patients with chronic alcoholism or poor nutrition from other causes. Prompt recognition of these infrequently seen syndromes is essential. This article outlines the medical treatment and nursing care needed to return these patients to a normal state. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Causes and Temporal Patterns of 30-Day Readmission Among Older Adults Hospitalized With Heart Failure With Preserved or Reduced Ejection Fraction.

    PubMed

    Goyal, Parag; Loop, Matthew; Chen, Ligong; Brown, Todd M; Durant, Raegan W; Safford, Monika M; Levitan, Emily B

    2018-04-23

    It is unknown whether causes and temporal patterns of 30-day readmission vary between heart failure (HF) with preserved ejection fraction (HFpEF) and HF with reduced ejection fraction (HFrEF). We sought to address this question by examining a 5% national sample of Medicare beneficiaries. We included individuals who experienced a hospitalization for HFpEF or HFrEF between 2007 and 2013. We identified causes of 30-day readmission based on primary discharge diagnosis and further classified causes of readmission as HF-related, non-HF cardiovascular-related, and non-cardiovascular-related. We calculated the cumulative incidence of these classifications for HFpEF and HFrEF in a competing risks model and calculated subdistribution hazard ratios of these classifications by comparing those with HFpEF and those with HFrEF. Among 60 640 Medicare beneficiaries, we identified 13 785 unique older adults hospitalized with HFpEF and 15 205 who were hospitalized with HFrEF. Noncardiovascular diagnoses represented the most common causes of 30-day readmission (HFpEF: 59%; HFrEF: 47%), a pattern that was observed for each week of the 30-day study period for both HFpEF and HFrEF participants. In comparing readmission diagnoses in an adjusted model, non-cardiovascular-related diagnoses were more common and HF-related diagnoses were less common in HFpEF participants. Non-cardiovascular-related diagnoses represented the most common causes of 30-day readmission following HF hospitalization for each week of the 30-day postdischarge period. HF diagnoses were less common among those with HFpEF compared with HFrEF. Future interventions aimed at reducing 30-day readmissions following an HF hospitalization would benefit from an increased focus on noncardiovascular comorbidity and interventions that target HFpEF and HFrEF separately. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  15. Pyrotechnic system failures: Causes and prevention

    NASA Technical Reports Server (NTRS)

    Bement, Laurence J.

    1988-01-01

    Although pyrotechnics have successfully accomplished many critical mechanical spacecraft functions, such as ignition, severance, jettisoning and valving (excluding propulsion), failures continue to occur. Provided is a listing of 84 failures of pyrotechnic hardware with completed design over a 23-year period, compiled informally by experts from every NASA Center, as well as the Air Force Space Division and the Naval Surface Warfare Center. Analyses are presented as to when and where these failures occurred, their technical source or cause, followed by the reasons why and how these kinds of failures persist. The major contributor is a fundamental lack of understanding of the functional mechanisms of pyrotechnic devices and systems, followed by not recognizing pyrotechnics as an engineering technology, insufficient manpower with hands-on experience, too few test facilities, and inadequate guidelines and specifications for design, development, qualification and acceptance. Recommendations are made on both a managerial and technical basis to prevent failures, increase reliability, improve existing and future designs, and develop the technology to meet future requirements.

  16. Common Cause Failure Modeling in Space Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Hark, Frank; Ring, Rob; Novack, Steven D.; Britton, Paul

    2015-01-01

    Common Cause Failures (CCFs) are a known and documented phenomenon that defeats system redundancy. CCFs are a set of dependent type of failures that can be caused for example by system environments, manufacturing, transportation, storage, maintenance, and assembly. Since there are many factors that contribute to CCFs, they can be reduced, but are difficult to eliminate entirely. Furthermore, failure databases sometimes fail to differentiate between independent and dependent CCF. Because common cause failure data is limited in the aerospace industry, the Probabilistic Risk Assessment (PRA) Team at Bastion Technology Inc. is estimating CCF risk using generic data collected by the Nuclear Regulatory Commission (NRC). Consequently, common cause risk estimates based on this database, when applied to other industry applications, are highly uncertain. Therefore, it is important to account for a range of values for independent and CCF risk and to communicate the uncertainty to decision makers. There is an existing methodology for reducing CCF risk during design, which includes a checklist of 40+ factors grouped into eight categories. Using this checklist, an approach to produce a beta factor estimate is being investigated that quantitatively relates these factors. In this example, the checklist will be tailored to space launch vehicles, a quantitative approach will be described, and an example of the method will be presented.

  17. Patterns of failure after involved field radiotherapy for locally advanced esophageal squamous cell carcinoma.

    PubMed

    Li, Duo-Jie; Li, Hong-Wei; He, Bin; Wang, Geng-Ming; Cai, Han-Fei; Duan, Shi-Miao; Liu, Jing-Jing; Zhang, Ya-Jun; Cui, Zhen; Jiang, Hao

    2016-01-01

    To retrospectively analyze the patterns of failure and the treatment effects of involved-field irradiation (IFI) on patients treated with locally advanced esophageal squamous cell carcinoma (ESCC) and to determine whether IFI is practicable in these patients. A total of 79 patients with locally advanced ESCC underwent three dimensional conformal (3D)CRT) or intensity modulated radiotherapy (IMRT) using IFI or elective nodal irradiation (ENI) according to the target volume. The patterns of failure were defined as local/regional, in-field, out)of)field regional lymph node (LN) and distant failure. With a median follow)up of 32.0 months, failures were observed in 66 (83.6%) patients. The cumulative incidence of local/regional failure (55.8 vs 52.8%) and in)field regional lymph node failure (25.6 vs 19.4%) showed no statistically significant difference between the IFI and the ENI group (p=0.526 and 0.215, respectively). Out)of)field nodal relapse rate of only 7.0% was seen in the IFI group. Three)year survival rates for the ENI and IFI group were 22.2 and 18.6%, respectively (p=0.240), and 3)year distant metastasis rates were 27.8 and 32.6%, respectively (p=0.180). The lung V10, V20, V30 and mean lung dose of the ENI group were greater than those of the IFI group, while the mean lung dose and V10 had statistically significant difference. The patterns of failure and survival rates in the IFI group were similar as in the ENI group; the regional recurrence and distant metastasis are the main cause of treatment failure. IFI is feasible for locally advanced ESCC. Further investigation is needed to increase local control and decrease distant metastasis in these patients.

  18. Chronic sublethal stress causes bee colony failure

    PubMed Central

    Bryden, John; Gill, Richard J; Mitton, Robert A A; Raine, Nigel E; Jansen, Vincent A A; Hodgson, David

    2013-01-01

    Current bee population declines and colony failures are well documented yet poorly understood and no single factor has been identified as a leading cause. The evidence is equivocal and puzzling: for instance, many pathogens and parasites can be found in both failing and surviving colonies and field pesticide exposure is typically sublethal. Here, we investigate how these results can be due to sublethal stress impairing colony function. We mathematically modelled stress on individual bees which impairs colony function and found how positive density dependence can cause multiple dynamic outcomes: some colonies fail while others thrive. We then exposed bumblebee colonies to sublethal levels of a neonicotinoid pesticide. The dynamics of colony failure, which we observed, were most accurately described by our model. We argue that our model can explain the enigmatic aspects of bee colony failures, highlighting an important role for sublethal stress in colony declines. PMID:24112478

  19. Homozygous Mutations in WEE2 Cause Fertilization Failure and Female Infertility.

    PubMed

    Sang, Qing; Li, Bin; Kuang, Yanping; Wang, Xueqian; Zhang, Zhihua; Chen, Biaobang; Wu, Ling; Lyu, Qifeng; Fu, Yonglun; Yan, Zheng; Mao, Xiaoyan; Xu, Yao; Mu, Jian; Li, Qiaoli; Jin, Li; He, Lin; Wang, Lei

    2018-04-05

    Fertilization is a fundamental process of development and is a prerequisite for successful human reproduction. In mice, although several receptor proteins have been shown to play important roles in the process of fertilization, only three genes have been shown to cause fertilization failure and infertility when deleted in vivo. In clinical practice, some infertility case subjects suffer from recurrent failure of in vitro fertilization and intracytoplasmic sperm injection attempts due to fertilization failure, but the genetic basis of fertilization failure in humans remains largely unknown. Wee2 is a key oocyte-specific kinase involved in the control of meiotic arrest in mice, but WEE2 has not been associated with any diseases in humans. In this study, we identified homozygous mutations in WEE2 that are responsible for fertilization failure in humans. All four independent affected individuals had homozygous loss-of-function missense mutations or homozygous frameshift protein-truncating mutations, and the phenotype of fertilization failure was shown to follow a Mendelian recessive inheritance pattern. All four mutations significantly decreased the amount of WEE2 protein in vitro and in affected individuals' oocytes in vivo, and they all led to abnormal serine phosphorylation of WEE2 and reduced tyrosine 15 phosphorylation of Cdc2 in vitro. In addition, injection of WEE2 cRNA into affected individuals' oocytes rescued the fertilization failure phenotype and led to the formation of blastocysts in vitro. This work presents a novel gene responsible for human fertilization failure and has implications for future therapeutic treatments for infertility cases. Copyright © 2018 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  20. Chronic sublethal stress causes bee colony failure.

    PubMed

    Bryden, John; Gill, Richard J; Mitton, Robert A A; Raine, Nigel E; Jansen, Vincent A A

    2013-12-01

    Current bee population declines and colony failures are well documented yet poorly understood and no single factor has been identified as a leading cause. The evidence is equivocal and puzzling: for instance, many pathogens and parasites can be found in both failing and surviving colonies and field pesticide exposure is typically sublethal. Here, we investigate how these results can be due to sublethal stress impairing colony function. We mathematically modelled stress on individual bees which impairs colony function and found how positive density dependence can cause multiple dynamic outcomes: some colonies fail while others thrive. We then exposed bumblebee colonies to sublethal levels of a neonicotinoid pesticide. The dynamics of colony failure, which we observed, were most accurately described by our model. We argue that our model can explain the enigmatic aspects of bee colony failures, highlighting an important role for sublethal stress in colony declines. © 2013 The Authors. Ecology Letters published by John Wiley & Sons Ltd and CNRS.

  1. Modeling Common Cause Failures of Thrusters on ISS Visiting Vehicles

    NASA Technical Reports Server (NTRS)

    Haught, Megan

    2014-01-01

    This paper discusses the methodology used to model common cause failures of thrusters on the International Space Station (ISS) Visiting Vehicles. The ISS Visiting Vehicles each have as many as 32 thrusters, whose redundancy makes them susceptible to common cause failures. The Global Alpha Model (as described in NUREG/CR-5485) can be used to represent the system common cause contribution, but NUREG/CR-5496 supplies global alpha parameters for groups only up to size six. Because of the large number of redundant thrusters on each vehicle, regression is used to determine parameter values for groups of size larger than six. An additional challenge is that Visiting Vehicle thruster failures must occur in specific combinations in order to fail the propulsion system; not all failure groups of a certain size are critical.

  2. Modeling Common Cause Failures of Thrusters on ISS Visiting Vehicles

    NASA Technical Reports Server (NTRS)

    Haught, Megan; Duncan, Gary

    2014-01-01

    This paper discusses the methodology used to model common cause failures of thrusters on the International Space Station (ISS) Visiting Vehicles. The ISS Visiting Vehicles each have as many as 32 thrusters, whose redundancy and similar design make them susceptible to common cause failures. The Global Alpha Model (as described in NUREG/CR-5485) can be used to represent the system common cause contribution, but NUREG/CR-5496 supplies global alpha parameters for groups only up to size six. Because of the large number of redundant thrusters on each vehicle, regression is used to determine parameter values for groups of size larger than six. An additional challenge is that Visiting Vehicle thruster failures must occur in specific combinations in order to fail the propulsion system; not all failure groups of a certain size are critical.

  3. A systems engineering approach to automated failure cause diagnosis in space power systems

    NASA Technical Reports Server (NTRS)

    Dolce, James L.; Faymon, Karl A.

    1987-01-01

    Automatic failure-cause diagnosis is a key element in autonomous operation of space power systems such as Space Station's. A rule-based diagnostic system has been developed for determining the cause of degraded performance. The knowledge required for such diagnosis is elicited from the system engineering process by using traditional failure analysis techniques. Symptoms, failures, causes, and detector information are represented with structured data; and diagnostic procedural knowledge is represented with rules. Detected symptoms instantiate failure modes and possible causes consistent with currently held beliefs about the likelihood of the cause. A diagnosis concludes with an explanation of the observed symptoms in terms of a chain of possible causes and subcauses.

  4. Causes of catastrophic failure in complex systems

    NASA Astrophysics Data System (ADS)

    Thomas, David A.

    2010-08-01

    Root causes of mission critical failures and major cost and schedule overruns in complex systems and programs are studied through the post-mortem analyses compiled for several examples, including the Hubble Space Telescope, the Challenger and Columbia Shuttle accidents, and the Three Mile Island nuclear power plant accident. The roles of organizational complexity, cognitive biases in decision making, the display of quantitative data, and cost and schedule pressure are all considered. Recommendations for mitigating the risk of similar failures in future programs are also provided.

  5. [What is the cause of failure of local anesthesia?].

    PubMed

    Vinckier, F

    2000-01-01

    Local anesthesia fails in 10% of cases of inferior alveolar nerve block and 7% of all cases of local anesthesia in general practice. Possible causes of failure are infection, wrong selection of local anesthetic solution, technical mistakes, anatomical variations with accessory innervation and anxiety of the patient. In this publication we discuss reasons for frequent failure in case of infection and in inferior alveolar nerve block. Understanding the mechanism of failure in local anesthesia, makes it possible to formulate guidelines to guarantee success. These measures are discussed in detail.

  6. Atrial Fibrillation and Heart Failure - Cause or Effect?

    PubMed

    Prabhu, Sandeep; Voskoboinik, Aleksandr; Kaye, David M; Kistler, Peter M

    2017-09-01

    There are emerging epidemics of atrial fibrillation (AF) and heart failure in most developed countries, with a significant health burden. Due to many shared pathophysiological mechanisms, which facilitate the maintenance of each condition, AF and heart failure co-exist in up to 30% of patients. In the circumstance where known structural causes of heart failure (such as myocardial infarction) are absent, patients presenting with both conditions present a unique challenge, particularly as the temporal relationship of each condition can often remain elusive from the clinical history. The question of whether the AF is driving, or significantly contributing to the left ventricular (LV) dysfunction, rather than merely a consequence of heart failure, has become ever more pertinent, especially as catheter ablation now offers a significant advancement over existing rhythm control strategies. This paper will review the inter-related physiological drivers of AF and heart failure before considering the implications from the outcomes of recent clinical trials in patients with AF and heart failure. Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

  7. Common-Cause Failure Treatment in Event Assessment: Basis for a Proposed New Model

    SciTech Connect

    Dana Kelly; Song-Hua Shen; Gary DeMoss

    2010-06-01

    Event assessment is an application of probabilistic risk assessment in which observed equipment failures and outages are mapped into the risk model to obtain a numerical estimate of the event’s risk significance. In this paper, we focus on retrospective assessments to estimate the risk significance of degraded conditions such as equipment failure accompanied by a deficiency in a process such as maintenance practices. In modeling such events, the basic events in the risk model that are associated with observed failures and other off-normal situations are typically configured to be failed, while those associated with observed successes and unchallenged components aremore » assumed capable of failing, typically with their baseline probabilities. This is referred to as the failure memory approach to event assessment. The conditioning of common-cause failure probabilities for the common cause component group associated with the observed component failure is particularly important, as it is insufficient to simply leave these probabilities at their baseline values, and doing so may result in a significant underestimate of risk significance for the event. Past work in this area has focused on the mathematics of the adjustment. In this paper, we review the Basic Parameter Model for common-cause failure, which underlies most current risk modelling, discuss the limitations of this model with respect to event assessment, and introduce a proposed new framework for common-cause failure, which uses a Bayesian network to model underlying causes of failure, and which has the potential to overcome the limitations of the Basic Parameter Model with respect to event assessment.« less

  8. The competing risks Cox model with auxiliary case covariates under weaker missing-at-random cause of failure.

    PubMed

    Nevo, Daniel; Nishihara, Reiko; Ogino, Shuji; Wang, Molin

    2017-08-04

    In the analysis of time-to-event data with multiple causes using a competing risks Cox model, often the cause of failure is unknown for some of the cases. The probability of a missing cause is typically assumed to be independent of the cause given the time of the event and covariates measured before the event occurred. In practice, however, the underlying missing-at-random assumption does not necessarily hold. Motivated by colorectal cancer molecular pathological epidemiology analysis, we develop a method to conduct valid analysis when additional auxiliary variables are available for cases only. We consider a weaker missing-at-random assumption, with missing pattern depending on the observed quantities, which include the auxiliary covariates. We use an informative likelihood approach that will yield consistent estimates even when the underlying model for missing cause of failure is misspecified. The superiority of our method over naive methods in finite samples is demonstrated by simulation study results. We illustrate the use of our method in an analysis of colorectal cancer data from the Nurses' Health Study cohort, where, apparently, the traditional missing-at-random assumption fails to hold.

  9. Failure Patterns in Patients with Esophageal Cancer Treated with Definitive Chemoradiation

    PubMed Central

    Welsh, James; Settle, Stephen H.; Amini, Arya; Xiao, Lianchun; Suzuki, Akihiro; Hayashi, Yuki; Hofstetter, Wayne; Komaki, Ritsuko; Liao, Zhongxing; Ajani, Jaffer A.

    2012-01-01

    Purpose Local failure after definitive chemoradiation therapy for unresectable esophageal cancer remains problematic. Little is known about the failure pattern based on modern day radiation treatment volumes. We hypothesized that most local failures would be within the gross tumor volume (GTV), where the bulk of the tumor burden resides. Methods and Materials We reviewed treatment volumes for 239 patients who underwent definitive chemoradiation therapy and compared this information with failure patterns on follow-up positron emission (PET). Failures were categorized as within the GTV, the larger clinical target volume (CTV, which encompasses microscopic disease), or the still larger planning target volume (PTV, which encompasses setup variability) or outside the radiation field. Results At a median follow-up time of 52.6 months (95% CI: 46.1 – 56.7 months), 119 patients (50%) had experienced local failure, 114 (48%) had distant failure, and 74 (31%) had no evidence of failure. Of all local failures, 107 (90%) were in the GTV, 27 (23%) in the CTV; and 14 (12%) in the PTV. In multivariate analysis, GTV failure was associated with tumor status (T3/T4 vs. T1/T2: OR=6.35, p value =0.002), change in standardized uptake value on PET before and after treatment (decrease >52%: OR=0.368, p value = 0.003) and tumor length (>8 cm: 4.08, p value = 0.009). Conclusions Most local failures after definitive chemoradiation for unresectable esophageal cancer occur in the GTV. Future therapeutic strategies should focus on enhancing local control. PMID:22565611

  10. Diseases causing end-stage renal failure in New South Wales.

    PubMed Central

    Stewart, J H; McCarthy, S W; Storey, B G; Roberts, B A; Gallery, E; Mahony, J F

    1975-01-01

    The nature of the original renal disease was determined in 403 consecutive cases of end-stage renal failure, in 317 of which the clinical diagnosis was corroborated by histological examination of the kidney. Five diseases accounted for 20 or more cases--glomerulonephritis (31% of the total), analgesic nephropathy (29%), primary vesicoureteral reflux (8%), essential hypertension (6%), and polycystic kidneys (5%). In only four cases did renal failure result from chronic pyelonephritis without a demonstrable primary cause. Greater use of micturating cystography and cystoscopy and routine urine testing for salicylate are advocated for earlier diagnosis of the major causes of "pyelonephritis". The incidence of end-stage renal failure in people aged 15-55 in New South Wales was estimated to be at least 34 new cases per million of total population each year. PMID:1090338

  11. Riser Pattern Is a Novel Predictor of Adverse Events in Heart Failure Patients With Preserved Ejection Fraction.

    PubMed

    Komori, Takahiro; Eguchi, Kazuo; Saito, Toshinobu; Hoshide, Satoshi; Kario, Kazuomi

    2017-01-25

    The cardiovascular prognosis of heart failure with preserved ejection fraction (HFpEF) has been shown to be similar to that of heart failure with reduced ejection fraction (HFrEF). It is unknown which factors predict cardiovascular outcome in HFpEF. We tested the hypothesis that the abnormal pattern of circadian blood pressure (BP) rhythm known as the riser BP pattern is associated with adverse outcomes in HFpEF.Methods and Results:We performed a prospective, observational cohort study of hospitalized HF patients who underwent ambulatory BP monitoring (ABPM). Five hundred and sixteen hospitalized HF patients (age, 69±13 years; male, n=321 [62%]; female, n=195 [38%]) were followed up for a median 20.9 months. The composite outcome consisting of all-cause mortality and cardiovascular events was observed in 220 patients. On Kaplan-Meier analysis, the riser BP pattern subgroup had a significantly higher incidence of the composite outcome than the other subgroups of HFpEF patients (HR, 3.01; 95% CI: 1.54-6.08, P<0.01), but not the HFrEF patients. The riser BP pattern was found to be a novel predictor of cardiovascular outcome in HFpEF patients.

  12. Heart failure caused by toxoplasmosis in a fennec fox (Fennecus zerda).

    PubMed

    Kottwitz, Jack J; Preziosi, Diane E; Miller, Margaret A; Ramos-Vara, Jose A; Maggs, David J; Bonagura, John D

    2004-01-01

    A male fennec fox (Fennecus zerda) kit was examined for lethargy, inappetence, and weight loss. Clinical findings included respiratory distress, a gallop rhythm, and retinochoroiditis. Radiography indicated pleural effusion and cardiomegaly. Echocardiographic findings included left ventricular dilatation, low left ventricular ejection fraction, and atrioventricular valvular regurgitation. Necropsy findings were compatible with a diagnosis of congestive heart failure caused by myocarditis. Histopathology showed a disseminated infection with Toxoplasma gondii causing myocarditis, skeletal polymyositis, gastrointestinal myositis, and panuveitis. Toxoplasma-induced myocarditis should be included in the differential diagnosis of heart failure and retinochoroiditis in the fennec fox.

  13. Causes of hatching failure in endangered birds

    PubMed Central

    Hemmings, N.; West, M.; Birkhead, T. R.

    2012-01-01

    About 10 per cent of birds' eggs fail to hatch, but the incidence of failure can be much higher in endangered species. Most studies fail to distinguish between infertility (due to a lack of sperm) and embryo mortality as the cause of hatching failure, yet doing so is crucial in order to understand the underlying problem. Using newly validated techniques to visualize sperm and embryonic tissue, we assessed the fertility status of unhatched eggs of five endangered species, including both wild and captive birds. All eggs were classified as ‘infertile’ when collected, but most were actually fertile with numerous sperm on the ovum. Eggs of captive birds had fewer sperm and were more likely to be infertile than those of wild birds. Our findings raise important questions regarding the management of captive breeding programmes. PMID:22977070

  14. Dialysis Arteriovenous Fistula Failure and Angioplasty: Intimal Hyperplasia and Other Causes of Access Failure.

    PubMed

    Duque, Juan C; Tabbara, Marwan; Martinez, Laisel; Cardona, Jose; Vazquez-Padron, Roberto I; Salman, Loay H

    2017-01-01

    The arteriovenous fistula (AVF) is the preferred hemodialysis access type because it has better patency rates and fewer complications than other access types. However, primary failure remains a common problem impeding AVF maturation and adding to patients' morbidity and mortality. Juxta-anastomotic (or inflow) stenosis is the most common reason leading to primary failure, and percutaneous transluminal angioplasty continues to be the gold-standard treatment with excellent success rates. Intimal hyperplasia (IH) has been traditionally blamed as the main pathophysiologic culprit, but new evidence raises doubts regarding the contribution of IH alone to primary failure. We report a 64-year-old man with a 2-stage brachiobasilic AVF that was complicated by failure 4 months after creation. An angiogram showed multiple juxta-anastomotic and midfistula stenotic lesions. Percutaneous transluminal angioplasty was successful in assisting maturation and subsequently cannulating the AVF for hemodialysis treatment. We failed to identify the underlying cause of stenosis because biopsy specimens from fistula tissue obtained at the time of transposition revealed no occlusive IH. This case emphasizes the need for additional research on factors contributing to AVF failure besides IH and highlights the need for more therapeutic options to reduce AVF failure rate. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  15. Interprofessional communication failures in acute care chains: How can we identify the causes?

    PubMed

    van Leijen-Zeelenberg, Janneke E; van Raak, Arno J A; Duimel-Peeters, Inge G P; Kroese, Mariëlle E A L; Brink, Peter R G; Vrijhoef, Hubertus J M

    2015-01-01

    Although communication failures between professionals in acute care delivery occur, explanations for these failures remain unclear. We aim to gain a deeper understanding of interprofessional communication failures by assessing two different explanations for them. A multiple case study containing six cases (i.e. acute care chains) was carried out in which semi-structured interviews, physical artifacts and archival records were used for data collection. Data were entered into matrices and the pattern-matching technique was used to examine the two complementary propositions. Based on the level of standardization and integration present in the acute care chains, the six acute care chains could be divided into two categories of care processes, with the care chains equally distributed among the categories. Failures in communication occurred in both groups. Communication routines were embedded within organizations and descriptions of communication routines in the entire acute care chain could not be found. Based on the results, failures in communication could not exclusively be explained by literature on process typology. Literature on organizational routines was useful to explain the occurrence of communication failures in the acute care chains. Organizational routines can be seen as repetitive action patterns and play an important role in organizations, as most processes are carried out by means of routines. The results of this study imply that it is useful to further explore the role of organizational routines on interprofessional communication in acute care chains to develop a solution for failures in handover practices.

  16. Riser Pattern: Another Determinant of Heart Failure With Preserved Ejection Fraction.

    PubMed

    Komori, Takahiro; Eguchi, Kazuo; Saito, Toshinobu; Hoshide, Satoshi; Kario, Kazuomi

    2016-10-01

    Paradoxical increase in blood pressure (BP) during sleep, exceeding those of awake BP, is called the "riser" BP pattern, and known as an abnormal circadian BP rhythm, has been reported to be associated with adverse cardiovascular prognoses. However, the significance of ambulatory BP in heart failure patients with preserved ejection fraction (HFpEF) has never been reported. Here, we tested our hypothesis that abnormal circadian BP rhythm is associated with HFpEF. The authors enrolled 508 patients with hospitalized HF (age 68±13 years; 315 men, 193 women). There were 232 cases of HFpEF and 276 cases of heart failure with reduced ejection fraction (HFrEF). The riser BP pattern was significantly more frequent in the HFpEF (28.9%) group compared with the HFrEF group (19.9%). In a multivariable logistic regression analysis, the riser BP pattern was associated with HFpEF (odds ratio, 1.73; 95% confidence interval, 1.02-2.91; P=.041) independent of the other covariates. In conclusion, the riser BP pattern was associated with HFpEF. ©2016 Wiley Periodicals, Inc.

  17. Acute Unilateral Vestibular Failure Does Not Cause Spatial Hemineglect.

    PubMed

    Conrad, Julian; Habs, Maximilian; Brandt, Thomas; Dieterich, Marianne

    2015-01-01

    Visuo-spatial neglect and vestibular disorders have common clinical findings and involve the same cortical areas. We questioned (1) whether visuo-spatial hemineglect is not only a disorder of spatial attention but may also reflect a disorder of higher cortical vestibular function and (2) whether a vestibular tone imbalance due to an acute peripheral dysfunction can also cause symptoms of neglect or extinction. Therefore, patients with an acute unilateral peripheral vestibular failure (VF) were tested for symptoms of hemineglect. Twenty-eight patients with acute VF were assessed for signs of vestibular deficits and spatial neglect using clinical measures and various common standardized paper-pencil tests. Neglect severity was evaluated further with the Center of Cancellation method. Pathological neglect test scores were correlated with the degree of vestibular dysfunction determined by the subjective visual vertical and caloric testing. Three patients showed isolated pathological scores in one or the other neglect test, either ipsilesionally or contralesionally to the VF. None of the patients fulfilled the diagnostic criteria of spatial hemineglect or extinction. A vestibular tone imbalance due to unilateral failure of the vestibular endorgan does not cause spatial hemineglect, but evidence indicates it causes mild attentional deficits in both visual hemifields.

  18. Injury pattern as an indication of seat belt failure in ejected vehicle occupants.

    PubMed

    Freeman, Michael D; Eriksson, Anders; Leith, Wendy

    2014-09-01

    Prior authors have suggested that when occupant ejection occurs in association with a seat belt failure, entanglement of the outboard upper extremity (OUE) with the retracting shoulder belt will invariably occur, leaving injury pattern evidence of belt use. In the present investigation, the authors assessed this theory using data accessed from the NASS-CDS for ejected front seat occupants of passenger vehicles. Logistic regression models were used to assess the associations between seat belt failure status and injuries. Injury types associated with seat belt failure were significant OUE and head injuries (OR = 3.87, [95% CI 1.2, 13.0] and 3.1, [95% CI 1.0, 9.7], respectively). The two injury types were found to be a predictor of seat belt use and subsequent failure only if combined with a high (≥0.8) precrash probability of belt use. The injury pattern associated with a seat belt failure-related ejection has limited use in the forensic investigation of crash-related ejections. © 2014 American Academy of Forensic Sciences.

  19. Scrub typhus causing neonatal hepatitis with acute liver failure-A case series.

    PubMed

    Vajpayee, Shailja; Gupta, R K; Gupta, M L

    2017-05-01

    Neonatal hepatitis with acute liver failure due to varied etiology including various infections is reported in the past. Scrub typhus as a cause of neonatal hepatitis has rarely been reported in literature. A high index of clinical suspicion is required for early diagnosis and timely treatment. Severity and prognosis of the disease varies widely because several different strains of Orientia tsutsugamushi exist with different virulence. Delayed diagnosis can result in complication and significant morbidity and mortality. Here, we report three cases of neonatal hepatitis with acute liver failure caused by scrub typhus to increase awareness.

  20. ISS Fiber Optic Failure Investigation Root Cause Report

    NASA Technical Reports Server (NTRS)

    Leidecker, Henning; Plante, Jeannette

    2000-01-01

    In August of 1999, Boeing Corporation (Boeing) engineers began investigating failures of optical fiber being used on International Space Station flight hardware. Catastrophic failures of the fiber were linked to a defect in the glass fiber. Following several meetings of Boeing and NASA engineers and managers, Boeing created and led an investigation team, which examined the reliability of the cable installed in the U.S. Lab. NASA Goddard Space Flight Center's Components Technologies and Radiation Effects Branch (GSFC) led a team investigating the root cause of the failures. Information was gathered from: regular telecons and other communications with the investigation team, investigative trips to the cable distributor's plant, the cable manufacturing plant and the fiber manufacturing plant (including a review of build records), destructive and non-destructive testing, and expertise supplied by scientists from Dupont, and Lucent-Bell Laboratories. Several theories were established early on which were not able to completely address the destructive physical analysis and experiential evidence. Lucent suggested hydrofluoric acid (HF) etching of the glass and successfully duplicated the "rocket engine" defect. Strength testing coupled with examination of the low strength break sites linked features in the polyimide coating with latent defect sites. The information provided below explains what was learned about the susceptibility of the pre-cabled fiber to failure when cabled as it was for Space Station and the nature of the latent defects.

  1. Shunting for hydrocephalus: analysis of techniques and failure patterns.

    PubMed

    Nigim, Fares; Critchlow, Jonathan F; Schneider, Benjamin E; Chen, Clark; Kasper, Ekkehard M

    2014-09-01

    Hydrocephalus is characterized by ventricular dilatation because of progressive accumulation of cerebrospinal fluid. Normal pressure hydrocephalus (NPH) affects a subset of patients representing a reversible clinical triad of gait disturbance, urinary incontinence, and dementia with normal cerebrospinal fluid pressure and composition. Various shunting procedures have been used for treatment, but techniques and outcomes remain under debate. The objective of this study was to evaluate the clinical outcomes of 232 patients with and without NPH after the first-time Ventriculoperitoneal shunt placement and assessed patterns of failure between December 2004 and December 2012. Mean age was 54.7 y in non-NPH and 71.9 y in NPH patients. We used open technique in 34.3% and laparoscopic technique in 65.7% of NPH patients and 32.7% and 67.3% of the non-NPH patients, respectively. A total of 36 of 232 patients displayed shunt failure, 16.4% in NPH and 15.2% in non-NPH patients. Twenty-three of 155 patients failed after laparoscopic and 13 of 77 failed after open placement. Proximal shunt failure was more frequent in the non-NPH cohort. Distal failures accounted for 13 of 232 cases, and the difference between laparoscopic (six of 155) and open failures (seven of 77) was profound, but not between NPH- and non-NPH patients. Shunt failures are related to the placement method. Non-NPH patients showed more proximal failures. NPH patients showed fewer proximal failures. Less distal failures were observed after laparoscopic ventriculoperitoneal shunt placement without significant differences between NPH and non-NPH patients. Beyond this, laparoscopic surgery carries distinct advantages such as shorter operating room times and hospital stays, which should translate into less use of pain medications, earlier mobilization, and a lower incidence of ileus. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Antimicrobial treatment failures in patients with community-acquired pneumonia: causes and prognostic implications.

    PubMed

    Arancibia, F; Ewig, S; Martinez, J A; Ruiz, M; Bauer, T; Marcos, M A; Mensa, J; Torres, A

    2000-07-01

    The aim of the study was to determine the causes and prognostic implications of antimicrobial treatment failures in patients with nonresponding and progressive life-threatening, community-acquired pneumonia. Forty-nine patients hospitalized with a presumptive diagnosis of community-acquired pneumonia during a 16-mo period, failure to respond to antimicrobial treatment, and documented repeated microbial investigation >/= 72 h after initiation of in-hospital antimicrobial treatment were recorded. A definite etiology of treatment failure could be established in 32 of 49 (65%) patients, and nine additional patients (18%) had a probable etiology. Treatment failures were mainly infectious in origin and included primary, persistent, and nosocomial infections (n = 10 [19%], 13 [24%], and 11 [20%] of causes, respectively). Definite but not probable persistent infections were mostly due to microbial resistance to the administered initial empiric antimicrobial treatment. Nosocomial infections were particularly frequent in patients with progressive pneumonia. Definite persistent infections and nosocomial infections had the highest associated mortality rates (75 and 88%, respectively). Nosocomial pneumonia was the only cause of treatment failure independently associated with death in multivariate analysis (RR, 16.7; 95% CI, 1.4 to 194.9; p = 0.03). We conclude that the detection of microbial resistance and the diagnosis of nosocomial pneumonia are the two major challenges in hospitalized patients with community-acquired pneumonia who do not respond to initial antimicrobial treatment. In order to establish these potentially life-threatening etiologies, a regular microbial reinvestigation seems mandatory for all patients presenting with antimicrobial treatment failures.

  3. Acute Unilateral Vestibular Failure Does Not Cause Spatial Hemineglect

    PubMed Central

    Conrad, Julian; Habs, Maximilian; Brandt, Thomas; Dieterich, Marianne

    2015-01-01

    Objectives Visuo-spatial neglect and vestibular disorders have common clinical findings and involve the same cortical areas. We questioned (1) whether visuo-spatial hemineglect is not only a disorder of spatial attention but may also reflect a disorder of higher cortical vestibular function and (2) whether a vestibular tone imbalance due to an acute peripheral dysfunction can also cause symptoms of neglect or extinction. Therefore, patients with an acute unilateral peripheral vestibular failure (VF) were tested for symptoms of hemineglect. Methods Twenty-eight patients with acute VF were assessed for signs of vestibular deficits and spatial neglect using clinical measures and various common standardized paper-pencil tests. Neglect severity was evaluated further with the Center of Cancellation method. Pathological neglect test scores were correlated with the degree of vestibular dysfunction determined by the subjective visual vertical and caloric testing. Results Three patients showed isolated pathological scores in one or the other neglect test, either ipsilesionally or contralesionally to the VF. None of the patients fulfilled the diagnostic criteria of spatial hemineglect or extinction. Conclusions A vestibular tone imbalance due to unilateral failure of the vestibular endorgan does not cause spatial hemineglect, but evidence indicates it causes mild attentional deficits in both visual hemifields. PMID:26247469

  4. A retrospective survey of the causes of bracket- and tube-bonding failures.

    PubMed

    Roelofs, Tom; Merkens, Nico; Roelofs, Jeroen; Bronkhorst, Ewald; Breuning, Hero

    2017-01-01

    To investigate the causes of bonding failures of orthodontic brackets and tubes and the effect of premedicating for saliva reduction. Premedication with atropine sulfate was administered randomly. Failure rate of brackets and tubes placed in a group of 158 consecutive patients was evaluated after a mean period of 67 weeks after bonding. The failure rate in the group without atropine sulfate premedication was 2.4%. In the group with premedication, the failure rate was 2.7%. The Cox regression analysis of these groups showed that atropine application did not lead to a reduction in bond failures. Statistically significant differences in the hazard ratio were found for the bracket regions and for the dental assistants who prepared for the bonding procedure. Premedication did not lead to fewer bracket failures. The roles of the dental assistant and patient in preventing failures was relevant. A significantly higher failure rate for orthodontic appliances was found in the posterior regions.

  5. Intravenous Milrinone Infusion Improves Congestive Heart Failure Caused by Diastolic Dysfunction

    PubMed Central

    Albrecht, Carlos A.; Giesler, Gregory M.; Kar, Biswajit; Hariharan, Ramesh; Delgado, Reynolds M.

    2005-01-01

    Although there have been significant advances in the medical treatment of heart failure patients with impaired systolic function, very little is known about the diagnosis and treatment of diastolic dysfunction. We report the cases of 3 patients in New York Heart Association functional class IV who had echocardiographically documented diastolic dysfunction as the main cause of heart failure. All 3 patients received medical therapy with long-term milrinone infusion. PMID:16107121

  6. Investigation into Cause of High Temperature Failure of Boiler Superheater Tube

    NASA Astrophysics Data System (ADS)

    Ghosh, D.; Ray, S.; Roy, H.; Shukla, A. K.

    2015-04-01

    The failure of the boiler tubes occur due to various reasons like creep, fatigue, corrosion and erosion. This paper highlights a case study of typical premature failure of a final superheater tube of 210 MW thermal power plant boiler. Visual examination, dimensional measurement, chemical analysis, oxide scale thickness measurement, microstructural examination are conducted as part of the investigations. Apart from these investigations, sulfur print, Energy Dispersive spectroscopy (EDS) and X ray diffraction analysis (XRD) are also conducted to ascertain the probable cause of failure of final super heater tube. Finally it has been concluded that the premature failure of the super heater tube can be attributed to the combination of localized high tube metal temperature and loss of metal from the outer surface due to high temperature corrosion. The corrective actions have also been suggested to avoid this type of failure in near future.

  7. Acute-On-Chronic Liver Failure: Causes, Clinical Characteristics and Predictors of Mortality.

    PubMed

    Tasneem, Abbas Ali; Luck, Nasir Hassan

    2017-01-01

    To determine the causes, characteristics and predictors of mortality in patients with acute-on-chronic liver failure (ACLF). Cross-sectional study. Department of Hepatogastroenterology, Sindh Institute of Urology and Transplantation, Karachi, from July 2014 to June 2016. All patients with acute-on-chronic liver disease (ACLD) with ages > 12 were included. Patients with ACLF, as defined by the Asian Pacific Association for the Study of Liver (APASL, 2014) were identified. Predictors of mortality were identified using chi-square or Fisher's exact test. Included in the study were 72 patients with mean age of 36.71 years, 46 (63.9%) being males. Among them, 61 developed ACLF. Commonest causes of chronic liver disease (CLD) were chronic viral hepatitis (37, 51.4%) and autoimmune hepatitis (14, 19.4%). Commonest causes of acute liver injury (ALI) were acute viral hepatitis (24, 33.3%) and drug induced liver injury (DILI) (17, 23.6%). Among those with ACLF, 24 (39.3%) patients died with median survival of 17.1 ±13.5 days. Mortality was significantly associated with Child Turcotte Pugh (CTP) score ≥13 (p=0.010), model for end-stage liver disease (MELD) score ≥30 (p=0.001), age >40 years (p=0.036), organ failures (OF) ≥3 (p <0.0001), portosystemic encephalopathy (PSE) (p <0.0001), renal failure (p <0.0001) and urosepsis (p <0.0001). Acute viral hepatitis and DILI are commonest causes of ACLF. Mortality is high in ACLF patients having OF ≥3, CTP ≥13, MELD ≥30, age >40 years, PSE, renal failure and urosepsis.

  8. Deregulation of ZPR1 causes respiratory failure in spinal muscular atrophy.

    PubMed

    Genabai, Naresh K; Kannan, Annapoorna; Ahmad, Saif; Jiang, Xiaoting; Bhatia, Kanchan; Gangwani, Laxman

    2017-08-15

    Spinal muscular atrophy (SMA) is caused by the low levels of survival motor neuron (SMN) protein and is characterized by motor neuron degeneration and muscle atrophy. Respiratory failure causes death in SMA but the underlying molecular mechanism is unknown. The zinc finger protein ZPR1 interacts with SMN. ZPR1 is down regulated in SMA patients. We report that ZPR1 functions downstream of SMN to regulate HoxA5 levels in phrenic motor neurons that control respiration. Spatiotemporal inactivation of Zpr1 gene in motor neurons down-regulates HoxA5 and causes defects in the function of phrenic motor neurons that results in respiratory failure and perinatal lethality in mice. Modulation in ZPR1 levels directly correlates and influences levels of HoxA5 transcription. In SMA mice, SMN-deficiency causes down-regulation of ZPR1 and HoxA5 that result in degeneration of phrenic motor neurons. Identification of ZPR1 and HoxA5 as potential targets provides a paradigm for developing strategies to treat respiratory distress in SMA.

  9. Readmission after pancreatic resection: causes and causality pattern.

    PubMed

    Sadot, Eran; Brennan, Murray F; Lee, Ser Yee; Allen, Peter J; Gönen, Mithat; Groeger, Jeffery S; Peter Kingham, T; D'Angelica, Michael I; DeMatteo, Ronald P; Jarnagin, William R; Fong, Yuman

    2014-12-01

    Readmission rates have been targeted for cost/reimbursement control. Our goal was to identify causes for readmission and delineate the pattern of early and late readmission. Between 2011 and 2012, a total of 490 patients underwent pancreaticoduodenectomy, distal pancreatectomy or central pancreatectomy. Logistic regression was used to identify predictors of readmission. K-medoids clustering was performed to identify the major readmission subgroups. Median postoperative length of stay (LOS) was 7 days, and the 30- and 90-day readmission rates were 23 and 29 %, respectively. The most common cause for 30-day readmissions was procedure-related infections (58 %), while the most common cause for 31-90-day readmissions was failure to thrive and chemotherapy-related symptoms (38 %). Independent predictors of 30-day readmissions were central pancreatectomy, discharge with a drain, pancreatic duct <3 mm, previous abdominal surgery, and postoperative LOS. Independent predictors for 31-90-day readmissions were age and preoperative serum carcinoembryonic antigen. Cancer-related covariates were more common in the 31-90-day readmission group. Postoperative carbohydrate antigen 19-9 levels were twofold higher in the 31-90-day readmission group compared with the no readmission group (p = 0.03). K-medoids clustering identified a subgroup where 74 % of readmissions occur at a median of 7 days after discharge. Readmissions after pancreatic operations are procedure-related in the first 30 days, but those after this period are influenced by the natural history of the underlying diagnosis. The readmission penalty policy should account for the timing of readmission and the natural history of the underlying disease and procedure. Early follow-up for patients at high risk for readmission may minimize early readmissions.

  10. Understanding the causes of kidney transplant failure: the dominant role of antibody-mediated rejection and nonadherence.

    PubMed

    Sellarés, J; de Freitas, D G; Mengel, M; Reeve, J; Einecke, G; Sis, B; Hidalgo, L G; Famulski, K; Matas, A; Halloran, P F

    2012-02-01

    We prospectively studied kidney transplants that progressed to failure after a biopsy for clinical indications, aiming to assign a cause to every failure. We followed 315 allograft recipients who underwent indication biopsies at 6 days to 32 years posttransplant. Sixty kidneys progressed to failure in the follow-up period (median 31.4 months). Failure was rare after T-cell-mediated rejection and acute kidney injury and common after antibody-mediated rejection or glomerulonephritis. We developed rules for using biopsy diagnoses, HLA antibody and clinical data to explain each failure. Excluding four with missing information, 56 failures were attributed to four causes: rejection 36 (64%), glomerulonephritis 10 (18%), polyoma virus nephropathy 4 (7%) and intercurrent events 6 (11%). Every rejection loss had evidence of antibody-mediated rejection by the time of failure. Among rejection losses, 17 of 36 (47%) had been independently identified as nonadherent by attending clinicians. Nonadherence was more frequent in patients who progressed to failure (32%) versus those who survived (3%). Pure T-cell-mediated rejection, acute kidney injury, drug toxicity and unexplained progressive fibrosis were not causes of loss. This prospective cohort indicates that many actual failures after indication biopsies manifest phenotypic features of antibody-mediated or mixed rejection and also underscores the major role of nonadherence. © 2011 The American Society of Transplantation and the American Society of Transplant Surgeons.

  11. Biallelic Mutations in NBAS Cause Recurrent Acute Liver Failure with Onset in Infancy.

    PubMed

    Haack, Tobias B; Staufner, Christian; Köpke, Marlies G; Straub, Beate K; Kölker, Stefan; Thiel, Christian; Freisinger, Peter; Baric, Ivo; McKiernan, Patrick J; Dikow, Nicola; Harting, Inga; Beisse, Flemming; Burgard, Peter; Kotzaeridou, Urania; Kühr, Joachim; Himbert, Urban; Taylor, Robert W; Distelmaier, Felix; Vockley, Jerry; Ghaloul-Gonzalez, Lina; Zschocke, Johannes; Kremer, Laura S; Graf, Elisabeth; Schwarzmayr, Thomas; Bader, Daniel M; Gagneur, Julien; Wieland, Thomas; Terrile, Caterina; Strom, Tim M; Meitinger, Thomas; Hoffmann, Georg F; Prokisch, Holger

    2015-07-02

    Acute liver failure (ALF) in infancy and childhood is a life-threatening emergency. Few conditions are known to cause recurrent acute liver failure (RALF), and in about 50% of cases, the underlying molecular cause remains unresolved. Exome sequencing in five unrelated individuals with fever-dependent RALF revealed biallelic mutations in NBAS. Subsequent Sanger sequencing of NBAS in 15 additional unrelated individuals with RALF or ALF identified compound heterozygous mutations in an additional six individuals from five families. Immunoblot analysis of mutant fibroblasts showed reduced protein levels of NBAS and its proposed interaction partner p31, both involved in retrograde transport between endoplasmic reticulum and Golgi. We recommend NBAS analysis in individuals with acute infantile liver failure, especially if triggered by fever. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  12. The pacemaker-twiddler's syndrome: an infrequent cause of pacemaker failure.

    PubMed

    Salahuddin, Mohammad; Cader, Fathima Aaysha; Nasrin, Sahela; Chowdhury, Mashhud Zia

    2016-01-20

    The pacemaker-twiddler's syndrome is an uncommon cause of pacemaker malfunction. It occurs due to unintentional or deliberate manipulation of the pacemaker pulse generator within its skin pocket by the patient. This causes coiling of the lead and its dislodgement, resulting in failure of ventricular pacing. More commonly reported among elderly females with impaired cognition, the phenomenon usually occurs in the first year following pacemaker implantation. Treatment involves repositioning of the dislodged leads and suture fixation of the lead and pulse generator within its pocket. An 87 year old Bangladeshi lady who underwent a single chamber ventricular pacemaker (VVI mode: i.e. ventricle paced, ventricle sensed, inhibitory mode) implantation with the indication of complete heart block, and presented to us again 7 weeks later, with syncopal attacks. She admitted to repeatedly manipulating the pacemaker generator in her left pectoral region. Physical examination revealed a heart rate of 42 beats/minute, blood pressure 140/80 mmHg and bilateral crackles on lung auscultation. She had no cognitive deficit. An immediate electrocardiogram showed complete heart block with pacemaker spikes and failure to capture. Chest X-ray showed coiled and retracted right ventricular lead and rotated pulse generator. An emergent temporary pace maker was set at a rate of 60 beats per minute. Subsequently, she underwent successful lead repositioning with strong counselling to avoid further twiddling. Twiddler's syndrome should be considered as a cause of pacemaker failure in elderly patients presenting with bradyarrythmias following pacemaker implantation. Chest X-ray and electrocardiograms are simple and easily-available first line investigations for its diagnosis. Lead repositioning is required, however proper patient education and counselling against further manipulation is paramount to long-term management.

  13. Survivorship analysis of failure pattern after revision total hip arthroplasty.

    PubMed

    Retpen, J B; Varmarken, J E; Jensen, J S

    1989-12-01

    Failure, defined as established indication for or performed re-revision of one or both components, was analyzed using survivorship methods in 306 revision total hip arthroplasties. The longevity of revision total hip arthroplasties was inferior to that of previously reported primary total hip arthroplasties. The overall survival curve was two-phased, with a late failure period associated with aseptic loosening of one or both components and an early failure period associated with causes of failure other than loosening. Separate survival curves for aseptic loosening of femoral and acetabular components showed late and almost simultaneous decline, but with a tendency toward a higher rate of failure for the femoral component. No differences in survival could be found between the Stanmore, Lubinus standard, and Lubinus long-stemmed femoral components. A short interval between the index operation and the revision and intraoperative and postoperative complications were risk factors for early failure. Young age was a risk factor for aseptic loosening of the femoral component. Intraoperative fracture of the femoral shaft was not a risk factor for secondary loosening. No difference in survival was found between primary cemented total arthroplasty and primary noncemented hemiarthroplasty.

  14. Riser Blood Pressure Pattern Is Associated With Mild Cognitive Impairment in Heart Failure Patients.

    PubMed

    Komori, Takahiro; Eguchi, Kazuo; Saito, Toshinobu; Nishimura, Yoshioki; Hoshide, Satoshi; Kario, Kazuomi

    2016-02-01

    The riser pattern, an abnormal blood pressure (BP) rhythm in which sleep BP exceeds awake BP, is a predictor of future stroke events. Although the riser pattern is caused by autonomic dysfunction, its significance in heart failure (HF) patients is not established. HF patients often suffered from cognitive impairment (CI), but the relationship between riser pattern and CI is not clearly understood. We tested the hypothesis that the riser pattern is associated with mild CI, a form of brain damage that could develop to dementia. We performed Mini-Mental State Examination (MMSE), ambulatory BP monitoring (ABPM), echocardiography, and blood tests in 444 HF patients just before leaving hospitals. Mild CI, a measure of cognitive function, was defined as the score <26. The mean age of the patients was 68±13 years; 61.5% were male; 22.5% were riser pattern. The MMSE score was significantly lower in the Riser group than in the Non-dipper and Dipper group (23±4 vs. 25±5, 26±4, respectively, P < 0.01). In multivariable logistic regression analysis, a riser pattern was significantly associated with mild CI (odds ratio 2.38, 95% confidence intervals 1.29-4.42, P < 0.01) after adjusting for significant covariates. The riser pattern was associated with mild CI in HF patients. An abnormal circadian BP rhythm in HF patients is clinically significant as a potential indicator of subclinical brain damage. © American Journal of Hypertension, Ltd 2015. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Virological patterns of HCV patients with failure to interferon-free regimens.

    PubMed

    Starace, Mario; Minichini, Carmine; De Pascalis, Stefania; Macera, Margherita; Occhiello, Laura; Messina, Vincenzo; Sangiovanni, Vincenzo; Adinolfi, Luigi E; Claar, Ernesto; Precone, Davide; Stornaiuolo, Gianfranca; Stanzione, Maria; Ascione, Tiziana; Caroprese, Mara; Zampino, Rosa; Parrilli, Gianpaolo; Gentile, Ivan; Brancaccio, Giuseppina; Iovinella, Vincenzo; Martini, Salvatore; Masarone, Mario; Fontanella, Luca; Masiello, Addolorata; Sagnelli, Evangelista; Punzi, Rodolfo; Salomone Megna, Angelo; Santoro, Renato; Gaeta, Giovanni B; Coppola, Nicola

    2018-05-01

    The study characterized the virological patterns and the resistance-associated substitutions (RASs) in patients with failure to IFN-free regimens enrolled in the real-life setting. All 87 consecutive HCV patients with failed IFN-free regimens, observed at the laboratory of the University of Campania, were enrolled. All patients had been treated with DAA regimens according to the HCV genotype, international guidelines, and local availability. Sanger sequencing of NS3, NS5A, and NS5B regions was performed at failure by home-made protocols. Of the 87 patients enrolled, 13 (14.9%) showed a misclassified HCV genotype, probably causing DAA failure, 16 had been treated with a sub-optimal DAA regimen, 19 with a simeprevir-based regimen and 39 with an optimal DAA regimen. A major RAS was identified more frequently in the simeprevir regimen group (68.4%) and in the optimal regimen group (74.4%) than in the sub-optimal regimen group (56.3%). The prevalence of RASs in NS3 was similar in the three groups (30.8-57.9%), that in NS5A higher in the optimal regimen group (71.8%) than in the sub-optimal regimen group (12.5%, P < 0.0001) and in the simeprevir regimen group (31.6%, P < 0.0005), and that in NS5B low in all groups (0-25%). RASs in two or more HCV regions were more frequently identified in the optimal regimen group (46.6%) than in the simeprevir-based regimen group (31.6%) and sub-optimal regimen group (18.7%). In our real-life population the prevalence of RASs was high, especially in NS3 and NS5A and in those treated with suitable DAA regimens. © 2018 Wiley Periodicals, Inc.

  16. Disparities in Patterns of Health Care Travel Among Inpatients Diagnosed With Congestive Heart Failure, Florida, 2011.

    PubMed

    Jia, Peng; Xierali, Imam M

    2015-09-17

    Congestive heart failure (CHF) is a major public health problem in the United States and is a leading cause of hospitalization in the elderly population. Understanding the health care travel patterns of CHF patients and their underlying cause is important to balance the supply and demand for local hospital resources. This article explores the nonclinical factors that prompt CHF patients to seek distant instead of local hospitalization. Local hospitalization was defined as inpatients staying within hospital service areas, and distant hospitalization was defined as inpatients traveling outside hospital service areas, based on individual hospital discharge data in 2011 generated by a Dartmouth-Swiss hybrid approach. Multiple logistic and linear regression models were used to compare the travel patterns of different groups of inpatients in Florida. Black patients, no-charge patients, patients living in large metropolitan areas, and patients with a low socioeconomic status were more likely to seek local hospitalization than were white patients, those who were privately insured, those who lived in rural areas, and those with a high socioeconomic status, respectively. Findings indicate that different populations diagnosed with CHF had different travel patterns for hospitalization. Changes or disruptions in local hospital supply could differentially affect different groups in a population. Policy makers could target efforts to CHF patients who are less likely to travel to seek treatment.

  17. Disparities in Patterns of Health Care Travel Among Inpatients Diagnosed With Congestive Heart Failure, Florida, 2011

    PubMed Central

    Xierali, Imam M.

    2015-01-01

    Introduction Congestive heart failure (CHF) is a major public health problem in the United States and is a leading cause of hospitalization in the elderly population. Understanding the health care travel patterns of CHF patients and their underlying cause is important to balance the supply and demand for local hospital resources. This article explores the nonclinical factors that prompt CHF patients to seek distant instead of local hospitalization. Methods Local hospitalization was defined as inpatients staying within hospital service areas, and distant hospitalization was defined as inpatients traveling outside hospital service areas, based on individual hospital discharge data in 2011 generated by a Dartmouth–Swiss hybrid approach. Multiple logistic and linear regression models were used to compare the travel patterns of different groups of inpatients in Florida. Results Black patients, no-charge patients, patients living in large metropolitan areas, and patients with a low socioeconomic status were more likely to seek local hospitalization than were white patients, those who were privately insured, those who lived in rural areas, and those with a high socioeconomic status, respectively. Conclusion Findings indicate that different populations diagnosed with CHF had different travel patterns for hospitalization. Changes or disruptions in local hospital supply could differentially affect different groups in a population. Policy makers could target efforts to CHF patients who are less likely to travel to seek treatment. PMID:26378896

  18. Kidney Failure

    MedlinePlus

    ... store Donate Now Give Monthly Give In Honor Kidney Failure (ESRD) Causes, Symptoms, & Treatments www.kidneyfund.org > ... Disaster preparedness Kidney failure/ESRD diet What causes kidney failure? In most cases, kidney failure is caused ...

  19. A clinical study of pattern and factors affecting outcome in Nigerian patients with advanced heart failure.

    PubMed

    Familoni, O B; Olunuga, T O; Olufemi, B W

    2007-01-01

    Advanced heart failure (AHF) accounts for about 25% of all cases of heart failure in Nigeria and is associated with a high mortality rate. To undertake a clinical study of the pattern and outcome of AHF in our hospitalised patients and to determine the parameters associated with mortality and survival in these patients. Eighty-two patients with AHF were studied between January 2003 and December 2005. Baseline blood chemistry and haemodynamics were determined. A congestion score, including orthopnoea, elevated jugular venous pressure, oedema, ascites and loud P2, was derived as well as a low perfusion score. Mortality was computed and risk estimated using the Pearson coefficient and log-ranking test. Cox regression analysis was used to identify the predictors of survival. AHF accounted for 43.6% of all hospitalised heart failure patients, with a total mortality of 67.1%. Hypertension was the commonest cause of AHF. The parameters associated with increased mortality rates included age (r = 0.671; p = 0.02), presence of atrial fibrillation (r = 0.532; p = 0.045) and estimated glomerular filtration rate (r = -0.486, p = 0.04). The majority of patients (54.8%) were in the 'wet and cold' congestion category. The congestion score correlated with mortality. The indices of survival included lower age, lower systolic blood pressure, being literate and lower congestion score. AHF was common in our cohorts of hospitalised heart failure patients and it was associated with a high mortality rate.

  20. Leveraging Client-Side DNS Failure Patterns to Identify Malicious Behaviors

    DTIC Science & Technology

    2015-09-28

    malicious behavior found in our dataset and (ii) to create ground truth to evaluate the system proposed in Section V. We begin by removing those cases that...2011. [10] S. Hao, N. Feamster, and R. Pandrangi, “Monitoring the Initial DNS Behavior of Malicious Domains,” in ACM IMC , 2011. [11] R. Perdisci et...distribution is unlimited. Leveraging Client-Side DNS Failure Patterns to Identify Malicious Behaviors The views, opinions and/or findings contained in

  1. Pathogenesis of apical periodontitis and the causes of endodontic failures.

    PubMed

    Nair, P N R

    2004-11-01

    Apical periodontitis is a sequel to endodontic infection and manifests itself as the host defense response to microbial challenge emanating from the root canal system. It is viewed as a dynamic encounter between microbial factors and host defenses at the interface between infected radicular pulp and periodontal ligament that results in local inflammation, resorption of hard tissues, destruction of other periapical tissues, and eventual formation of various histopathological categories of apical periodontitis, commonly referred to as periapical lesions. The treatment of apical periodontitis, as a disease of root canal infection, consists of eradicating microbes or substantially reducing the microbial load from the root canal and preventing re-infection by orthograde root filling. The treatment has a remarkably high degree of success. Nevertheless, endodontic treatment can fail. Most failures occur when treatment procedures, mostly of a technical nature, have not reached a satisfactory standard for the control and elimination of infection. Even when the highest standards and the most careful procedures are followed, failures still occur. This is because there are root canal regions that cannot be cleaned and obturated with existing equipments, materials, and techniques, and thus, infection can persist. In very rare cases, there are also factors located within the inflamed periapical tissue that can interfere with post-treatment healing of the lesion. The data on the biological causes of endodontic failures are recent and scattered in various journals. This communication is meant to provide a comprehensive overview of the etio-pathogenesis of apical periodontitis and the causes of failed endodontic treatments that can be visualized in radiographs as asymptomatic post-treatment periapical radiolucencies.

  2. Tsunamis caused by submarine slope failures along western Great Bahama Bank

    NASA Astrophysics Data System (ADS)

    Schnyder, Jara S. D.; Eberli, Gregor P.; Kirby, James T.; Shi, Fengyan; Tehranirad, Babak; Mulder, Thierry; Ducassou, Emmanuelle; Hebbeln, Dierk; Wintersteller, Paul

    2016-11-01

    Submarine slope failures are a likely cause for tsunami generation along the East Coast of the United States. Among potential source areas for such tsunamis are submarine landslides and margin collapses of Bahamian platforms. Numerical models of past events, which have been identified using high-resolution multibeam bathymetric data, reveal possible tsunami impact on Bimini, the Florida Keys, and northern Cuba. Tsunamis caused by slope failures with terminal landslide velocity of 20 ms-1 will either dissipate while traveling through the Straits of Florida, or generate a maximum wave of 1.5 m at the Florida coast. Modeling a worst-case scenario with a calculated terminal landslide velocity generates a wave of 4.5 m height. The modeled margin collapse in southwestern Great Bahama Bank potentially has a high impact on northern Cuba, with wave heights between 3.3 to 9.5 m depending on the collapse velocity. The short distance and travel time from the source areas to densely populated coastal areas would make the Florida Keys and Miami vulnerable to such low-probability but high-impact events.

  3. Tsunamis caused by submarine slope failures along western Great Bahama Bank.

    PubMed

    Schnyder, Jara S D; Eberli, Gregor P; Kirby, James T; Shi, Fengyan; Tehranirad, Babak; Mulder, Thierry; Ducassou, Emmanuelle; Hebbeln, Dierk; Wintersteller, Paul

    2016-11-04

    Submarine slope failures are a likely cause for tsunami generation along the East Coast of the United States. Among potential source areas for such tsunamis are submarine landslides and margin collapses of Bahamian platforms. Numerical models of past events, which have been identified using high-resolution multibeam bathymetric data, reveal possible tsunami impact on Bimini, the Florida Keys, and northern Cuba. Tsunamis caused by slope failures with terminal landslide velocity of 20 ms -1 will either dissipate while traveling through the Straits of Florida, or generate a maximum wave of 1.5 m at the Florida coast. Modeling a worst-case scenario with a calculated terminal landslide velocity generates a wave of 4.5 m height. The modeled margin collapse in southwestern Great Bahama Bank potentially has a high impact on northern Cuba, with wave heights between 3.3 to 9.5 m depending on the collapse velocity. The short distance and travel time from the source areas to densely populated coastal areas would make the Florida Keys and Miami vulnerable to such low-probability but high-impact events.

  4. Multiple imputation methods for nonparametric inference on cumulative incidence with missing cause of failure

    PubMed Central

    Lee, Minjung; Dignam, James J.; Han, Junhee

    2014-01-01

    We propose a nonparametric approach for cumulative incidence estimation when causes of failure are unknown or missing for some subjects. Under the missing at random assumption, we estimate the cumulative incidence function using multiple imputation methods. We develop asymptotic theory for the cumulative incidence estimators obtained from multiple imputation methods. We also discuss how to construct confidence intervals for the cumulative incidence function and perform a test for comparing the cumulative incidence functions in two samples with missing cause of failure. Through simulation studies, we show that the proposed methods perform well. The methods are illustrated with data from a randomized clinical trial in early stage breast cancer. PMID:25043107

  5. Patterns of failure after the reduced volume approach for elective nodal irradiation in nasopharyngeal carcinoma.

    PubMed

    Seol, Ki Ho; Lee, Jeong Eun

    2016-03-01

    To evaluate the patterns of nodal failure after radiotherapy (RT) with the reduced volume approach for elective neck nodal irradiation (ENI) in nasopharyngeal carcinoma (NPC). Fifty-six NPC patients who underwent definitive chemoradiotherapy with the reduced volume approach for ENI were reviewed. The ENI included retropharyngeal and level II lymph nodes, and only encompassed the echelon inferior to the involved level to eliminate the entire neck irradiation. Patients received either moderate hypofractionated intensity-modulated RT for a total of 72.6 Gy (49.5 Gy to elective nodal areas) or a conventional fractionated three-dimensional conformal RT for a total of 68.4-72 Gy (39.6-45 Gy to elective nodal areas). Patterns of failure, locoregional control, and survival were analyzed. The median follow-up was 38 months (range, 3 to 80 months). The out-of-field nodal failure when omitting ENI was none. Three patients developed neck recurrences (one in-field recurrence in the 72.6 Gy irradiated nodal area and two in the elective irradiated region of 39.6 Gy). Overall disease failure at any site developed in 11 patients (19.6%). Among these, there were six local failures (10.7%), three regional failures (5.4%), and five distant metastases (8.9%). The 3-year locoregional control rate was 87.1%, and the distant failure-free rate was 90.4%; disease-free survival and overall survival at 3 years was 80% and 86.8%, respectively. No patient developed nodal failure in the omitted ENI site. Our investigation has demonstrated that the reduced volume approach for ENI appears to be a safe treatment approach in NPC.

  6. Patterns of failure after the reduced volume approach for elective nodal irradiation in nasopharyngeal carcinoma

    PubMed Central

    Seol, Ki Ho

    2016-01-01

    Purpose To evaluate the patterns of nodal failure after radiotherapy (RT) with the reduced volume approach for elective neck nodal irradiation (ENI) in nasopharyngeal carcinoma (NPC). Materials and Methods Fifty-six NPC patients who underwent definitive chemoradiotherapy with the reduced volume approach for ENI were reviewed. The ENI included retropharyngeal and level II lymph nodes, and only encompassed the echelon inferior to the involved level to eliminate the entire neck irradiation. Patients received either moderate hypofractionated intensity-modulated RT for a total of 72.6 Gy (49.5 Gy to elective nodal areas) or a conventional fractionated three-dimensional conformal RT for a total of 68.4–72 Gy (39.6–45 Gy to elective nodal areas). Patterns of failure, locoregional control, and survival were analyzed. Results The median follow-up was 38 months (range, 3 to 80 months). The out-of-field nodal failure when omitting ENI was none. Three patients developed neck recurrences (one in-field recurrence in the 72.6 Gy irradiated nodal area and two in the elective irradiated region of 39.6 Gy). Overall disease failure at any site developed in 11 patients (19.6%). Among these, there were six local failures (10.7%), three regional failures (5.4%), and five distant metastases (8.9%). The 3-year locoregional control rate was 87.1%, and the distant failure-free rate was 90.4%; disease-free survival and overall survival at 3 years was 80% and 86.8%, respectively. Conclusion No patient developed nodal failure in the omitted ENI site. Our investigation has demonstrated that the reduced volume approach for ENI appears to be a safe treatment approach in NPC. PMID:27104162

  7. Cheyne-Stokes respiration in patients with congestive heart failure: causes and consequences.

    PubMed

    Lorenzi-Filho, Geraldo; Genta, Pedro R; Figueiredo, Adelaide C; Inoue, Daniel

    2005-08-01

    Cheyne-Stokes respiration is a form of periodic breathing in which central apneas and hypopneas alternate with periods of hyperventilation, producing a waxing and waning pattern of tidal volume. This review focuses on the causes and consequences of Cheyne-Stokes respiration in patients with congestive heart failure, in whom the prevalence is strikingly high and ranges from 30% to 50%. Several factors have been implicated in the genesis of Cheyne-Stokes respiration, including low cardiac output and recurrent hypoxia. The key pathophysiological mechanism triggering Cheyne-Stokes respiration is hyperventilation and low arterial CO2 (PaCO2) that when below the apneic threshold triggers a central apnea. Hyperventilation is associated with pulmonary congestion, and Cheyne-Stokes respiration is more prone to occur during sleep, when the respiratory system is mainly dependent on chemical control. It is associated with recurrent dips in oxygen saturation and arousals from sleep, with oscillations in blood pressure and heart rate, sympathetic activation and increased risk of ventricular tachycardia. Cheyne-Stokes respiration is an independent marker of poor prognosis and may participate in a vicious cycle, further stressing the failing heart.

  8. Patterns of Failure After Proton Therapy in Medulloblastoma; Linear Energy Transfer Distributions and Relative Biological Effectiveness Associations for Relapses

    SciTech Connect

    Sethi, Roshan V.; Giantsoudi, Drosoula; Raiford, Michael

    2014-03-01

    Purpose: The pattern of failure in medulloblastoma patients treated with proton radiation therapy is unknown. For this increasingly used modality, it is important to ensure that outcomes are comparable to those in modern photon series. It has been suggested this pattern may differ from photons because of variations in linear energy transfer (LET) and relative biological effectiveness (RBE). In addition, the use of matching fields for delivery of craniospinal irradiation (CSI) may influence patterns of relapse. Here we report the patterns of failure after the use of protons, compare it to that in the available photon literature, and determine themore » LET and RBE values in areas of recurrence. Methods and Materials: Retrospective review of patients with medulloblastoma treated with proton radiation therapy at Massachusetts General Hospital (MGH) between 2002 and 2011. We documented the locations of first relapse. Discrete failures were contoured on the original planning computed tomography scan. Monte Carlo calculation methods were used to estimate the proton LET distribution. Models were used to estimate RBE values based on the LET distributions. Results: A total of 109 patients were followed for a median of 38.8 months (range, 1.4-119.2 months). Of the patients, 16 experienced relapse. Relapse involved the supratentorial compartment (n=8), spinal compartment (n=11), and posterior fossa (n=5). Eleven failures were isolated to a single compartment; 6 failures in the spine, 4 failures in the supratentorium, and 1 failure in the posterior fossa. The remaining patients had multiple sites of disease. One isolated spinal failure occurred at the spinal junction of 2 fields. None of the 70 patients treated with an involved-field-only boost failed in the posterior fossa outside of the tumor bed. We found no correlation between Monte Carlo-calculated LET distribution and regions of recurrence. Conclusions: The most common site of failure in patients treated with protons

  9. Finite Element Creep-Fatigue Analysis of a Welded Furnace Roll for Identifying Failure Root Cause

    NASA Astrophysics Data System (ADS)

    Yang, Y. P.; Mohr, W. C.

    2015-11-01

    Creep-fatigue induced failures are often observed in engineering components operating under high temperature and cyclic loading. Understanding the creep-fatigue damage process and identifying failure root cause are very important for preventing such failures and improving the lifetime of engineering components. Finite element analyses including a heat transfer analysis and a creep-fatigue analysis were conducted to model the cyclic thermal and mechanical process of a furnace roll in a continuous hot-dip coating line. Typically, the roll has a short life, <1 year, which has been a problem for a long time. The failure occurred in the weld joining an end bell to a roll shell and resulted in the complete 360° separation of the end bell from the roll shell. The heat transfer analysis was conducted to predict the temperature history of the roll by modeling heat convection from hot air inside the furnace. The creep-fatigue analysis was performed by inputting the predicted temperature history and applying mechanical loads. The analysis results showed that the failure was resulted from a creep-fatigue mechanism rather than a creep mechanism. The difference of material properties between the filler metal and the base metal is the root cause for the roll failure, which induces higher creep strain and stress in the interface between the weld and the HAZ.

  10. Patterns of relapse and prognosis after bevacizumab failure in recurrent glioblastoma

    PubMed Central

    Iwamoto, F M.; Abrey, L E.; Beal, K; Gutin, P H.; Rosenblum, M K.; Reuter, V E.; DeAngelis, L M.; Lassman, A B.

    2009-01-01

    Background: Bevacizumab has recently been approved by the US Food and Drug Administration for recurrent glioblastoma (GBM). However, patterns of relapse, prognosis, and outcome of further therapy after bevacizumab failure have not been studied systematically. Methods: We identified patients at Memorial Sloan-Kettering Cancer Center with recurrent GBM who discontinued bevacizumab because of progressive disease. Results: There were 37 patients (26 men with a median age of 54 years). The most common therapies administered concurrently with bevacizumab were irinotecan (43%) and hypofractionated reirradiation (38%). The median overall survival (OS) after progressive disease on bevacizumab was 4.5 months; 34 patients died. At the time bevacizumab was discontinued for tumor progression, 17 patients (46%) had an increase in the size of enhancement at the initial site of disease (local recurrence), 6 (16%) had a new enhancing lesion outside of the initial site of disease (multifocal), and 13 (35%) had progression of predominantly nonenhancing tumor. Factors associated with shorter OS after discontinuing bevacizumab were lower performance status and nonenhancing pattern of recurrence. Additional salvage chemotherapy after bevacizumab failure was given to 19 patients. The median progression-free survival (PFS) among these 19 patients was 2 months, the median OS was 5.2 months, and the 6-month PFS rate was 0%. Conclusions: Contrast enhanced MRI does not adequately assess disease status during bevacizumab therapy for recurrent glioblastoma (GBM). A nonenhancing tumor pattern of progression is common after treatment with bevacizumab for GBM and is correlated with worse survival. Treatments after bevacizumab failure provide only transient tumor control. GLOSSARY CA9 = carbonic anhydrase 9; CI = confidence interval; FDG = [18F]fluorodeoxyglucose; FLAIR = fluid-attenuation inversion recovery; GBM = glioblastoma; HIF-1 α = hypoxia-inducible factor 1α; KPS = Karnofsky performance

  11. Identification of Modeling Approaches To Support Common-Cause Failure Analysis

    SciTech Connect

    Korsah, Kofi; Wood, Richard Thomas

    2015-06-01

    Experience with applying current guidance and practices for common-cause failure (CCF) mitigation to digital instrumentation and control (I&C) systems has proven problematic, and the regulatory environment has been unpredictable. The impact of CCF vulnerability is to inhibit I&C modernization and, thereby, challenge the long-term sustainability of existing plants. For new plants and advanced reactor concepts, the issue of CCF vulnerability for highly integrated digital I&C systems imposes a design burden resulting in higher costs and increased complexity. The regulatory uncertainty regarding which mitigation strategies are acceptable (e.g., what diversity is needed and how much is sufficient) drives designers to adoptmore » complicated, costly solutions devised for existing plants. The conditions that constrain the transition to digital I&C technology by the U.S. nuclear industry require crosscutting research to resolve uncertainty, demonstrate necessary characteristics, and establish an objective basis for qualification of digital technology for usage in Nuclear Power Plant (NPP) I&C applications. To fulfill this research need, Oak Ridge National Laboratory is conducting an investigation into mitigation of CCF vulnerability for nuclear-qualified applications. The outcome of this research is expected to contribute to a fundamentally sound, comprehensive technical basis for establishing the qualification of digital technology for nuclear power applications. This report documents the investigation of modeling approaches for representing failure of I&C systems. Failure models are used when there is a need to analyze how the probability of success (or failure) of a system depends on the success (or failure) of individual elements. If these failure models are extensible to represent CCF, then they can be employed to support analysis of CCF vulnerabilities and mitigation strategies. Specifically, the research findings documented in this report identify modeling

  12. Questioning the Role of Requirements Engineering in the Causes of Safety-Critical Software Failures

    NASA Technical Reports Server (NTRS)

    Johnson, C. W.; Holloway, C. M.

    2006-01-01

    Many software failures stem from inadequate requirements engineering. This view has been supported both by detailed accident investigations and by a number of empirical studies; however, such investigations can be misleading. It is often difficult to distinguish between failures in requirements engineering and problems elsewhere in the software development lifecycle. Further pitfalls arise from the assumption that inadequate requirements engineering is a cause of all software related accidents for which the system fails to meet its requirements. This paper identifies some of the problems that have arisen from an undue focus on the role of requirements engineering in the causes of major accidents. The intention is to provoke further debate within the emerging field of forensic software engineering.

  13. Tsunamis caused by submarine slope failures along western Great Bahama Bank

    PubMed Central

    Schnyder, Jara S.D.; Eberli, Gregor P.; Kirby, James T.; Shi, Fengyan; Tehranirad, Babak; Mulder, Thierry; Ducassou, Emmanuelle; Hebbeln, Dierk; Wintersteller, Paul

    2016-01-01

    Submarine slope failures are a likely cause for tsunami generation along the East Coast of the United States. Among potential source areas for such tsunamis are submarine landslides and margin collapses of Bahamian platforms. Numerical models of past events, which have been identified using high-resolution multibeam bathymetric data, reveal possible tsunami impact on Bimini, the Florida Keys, and northern Cuba. Tsunamis caused by slope failures with terminal landslide velocity of 20 ms−1 will either dissipate while traveling through the Straits of Florida, or generate a maximum wave of 1.5 m at the Florida coast. Modeling a worst-case scenario with a calculated terminal landslide velocity generates a wave of 4.5 m height. The modeled margin collapse in southwestern Great Bahama Bank potentially has a high impact on northern Cuba, with wave heights between 3.3 to 9.5 m depending on the collapse velocity. The short distance and travel time from the source areas to densely populated coastal areas would make the Florida Keys and Miami vulnerable to such low-probability but high-impact events. PMID:27811961

  14. Revealing catastrophic failure of leaf networks under stress

    PubMed Central

    Brodribb, Timothy J.; Bienaimé, Diane; Marmottant, Philippe

    2016-01-01

    The intricate patterns of veins that adorn the leaves of land plants are among the most important networks in biology. Water flows in these leaf irrigation networks under tension and is vulnerable to embolism-forming cavitations, which cut off water supply, ultimately causing leaf death. Understanding the ways in which plants structure their vein supply network to protect against embolism-induced failure has enormous ecological and evolutionary implications, but until now there has been no way of observing dynamic failure in natural leaf networks. Here we use a new optical method that allows the initiation and spread of embolism bubbles in the leaf network to be visualized. Examining embolism-induced failure of architecturally diverse leaf networks, we found that conservative rules described the progression of hydraulic failure within veins. The most fundamental rule was that within an individual venation network, susceptibility to embolism always increased proportionally with the size of veins, and initial nucleation always occurred in the largest vein. Beyond this general framework, considerable diversity in the pattern of network failure was found between species, related to differences in vein network topology. The highest-risk network was found in a fern species, where single events caused massive disruption to leaf water supply, whereas safer networks in angiosperm leaves contained veins with composite properties, allowing a staged failure of water supply. These results reveal how the size structure of leaf venation is a critical determinant of the spread of embolism damage to leaves during drought. PMID:27071104

  15. Revealing catastrophic failure of leaf networks under stress.

    PubMed

    Brodribb, Timothy J; Bienaimé, Diane; Marmottant, Philippe

    2016-04-26

    The intricate patterns of veins that adorn the leaves of land plants are among the most important networks in biology. Water flows in these leaf irrigation networks under tension and is vulnerable to embolism-forming cavitations, which cut off water supply, ultimately causing leaf death. Understanding the ways in which plants structure their vein supply network to protect against embolism-induced failure has enormous ecological and evolutionary implications, but until now there has been no way of observing dynamic failure in natural leaf networks. Here we use a new optical method that allows the initiation and spread of embolism bubbles in the leaf network to be visualized. Examining embolism-induced failure of architecturally diverse leaf networks, we found that conservative rules described the progression of hydraulic failure within veins. The most fundamental rule was that within an individual venation network, susceptibility to embolism always increased proportionally with the size of veins, and initial nucleation always occurred in the largest vein. Beyond this general framework, considerable diversity in the pattern of network failure was found between species, related to differences in vein network topology. The highest-risk network was found in a fern species, where single events caused massive disruption to leaf water supply, whereas safer networks in angiosperm leaves contained veins with composite properties, allowing a staged failure of water supply. These results reveal how the size structure of leaf venation is a critical determinant of the spread of embolism damage to leaves during drought.

  16. NALP3-mediated inflammation is a principal cause of progressive renal failure in oxalate nephropathy

    PubMed Central

    Knauf, Felix; Asplin, John R.; Granja, Ignacio; Schmidt, Insa M.; Moeckel, Gilbert; David, Rachel; Flavell, Richard A.; Aronson, Peter S.

    2013-01-01

    Oxalate nephropathy with renal failure is caused by multiple disorders causing hyperoxaluria due to either overproduction of oxalate (primary hyperoxaluria) or excessive absorption of dietary oxalate (enteric hyperoxaluria). To study the etiology of renal failure in crystal-induced kidney disease, we created a model of progressive oxalate nephropathy by feeding mice a diet high in soluble oxalate (high oxalate in the absence of dietary calcium). Renal histology was characterized by intratubular calcium-oxalate crystal deposition with an inflammatory response in the surrounding interstitium. Oxalate nephropathy was not found in mice fed a high oxalate diet that also contained calcium. NALP3, also known as cryopyrin, has been implicated in crystal-associated diseases such as gout and silicosis. Mice fed the diet high in soluble oxalate demonstrated increased NALP3 expression in the kidney. Nalp3-null mice were completely protected from the progressive renal failure and death that occurred in wild-type mice fed the diet high in soluble oxalate. NALP3-deficiency did not affect oxalate homeostasis, thereby excluding differences in intestinal oxalate handling to explain the observed phenotype. Thus, progressive renal failure in oxalate nephropathy results primarily from NALP3-mediated inflammation. PMID:23739234

  17. The hot (invisible?) hand: can time sequence patterns of success/failure in sports be modeled as repeated random independent trials?

    PubMed

    Yaari, Gur; Eisenmann, Shmuel

    2011-01-01

    The long lasting debate initiated by Gilovich, Vallone and Tversky in [Formula: see text] is revisited: does a "hot hand" phenomenon exist in sports? Hereby we come back to one of the cases analyzed by the original study, but with a much larger data set: all free throws taken during five regular seasons ([Formula: see text]) of the National Basketball Association (NBA). Evidence supporting the existence of the "hot hand" phenomenon is provided. However, while statistical traces of this phenomenon are observed in the data, an open question still remains: are these non random patterns a result of "success breeds success" and "failure breeds failure" mechanisms or simply "better" and "worse" periods? Although free throws data is not adequate to answer this question in a definite way, we speculate based on it, that the latter is the dominant cause behind the appearance of the "hot hand" phenomenon in the data.

  18. A method for automatically optimizing medical devices for treating heart failure: designing polymeric injection patterns.

    PubMed

    Wenk, Jonathan F; Wall, Samuel T; Peterson, Robert C; Helgerson, Sam L; Sabbah, Hani N; Burger, Mike; Stander, Nielen; Ratcliffe, Mark B; Guccione, Julius M

    2009-12-01

    Heart failure continues to present a significant medical and economic burden throughout the developed world. Novel treatments involving the injection of polymeric materials into the myocardium of the failing left ventricle (LV) are currently being developed, which may reduce elevated myofiber stresses during the cardiac cycle and act to retard the progression of heart failure. A finite element (FE) simulation-based method was developed in this study that can automatically optimize the injection pattern of the polymeric "inclusions" according to a specific objective function, using commercially available software tools. The FE preprocessor TRUEGRID((R)) was used to create a parametric axisymmetric LV mesh matched to experimentally measured end-diastole and end-systole metrics from dogs with coronary microembolization-induced heart failure. Passive and active myocardial material properties were defined by a pseudo-elastic-strain energy function and a time-varying elastance model of active contraction, respectively, that were implemented in the FE software LS-DYNA. The companion optimization software LS-OPT was used to communicate directly with TRUEGRID((R)) to determine FE model parameters, such as defining the injection pattern and inclusion characteristics. The optimization resulted in an intuitive optimal injection pattern (i.e., the one with the greatest number of inclusions) when the objective function was weighted to minimize mean end-diastolic and end-systolic myofiber stress and ignore LV stroke volume. In contrast, the optimization resulted in a nonintuitive optimal pattern (i.e., 3 inclusions longitudinallyx6 inclusions circumferentially) when both myofiber stress and stroke volume were incorporated into the objective function with different weights.

  19. Star fruit (Averrhoa carambola) intoxication: an important cause of consciousness disturbance in patients with renal failure.

    PubMed

    Chang, Chin-Tung; Chen, Yung-Chang; Fang, Ji-Tseng; Huang, Chiu-Ching

    2002-05-01

    Star fruit intoxication is a rare cause of consciousness disturbance in patients with renal failure. Most cases in the literature are uremic patients on maintenance dialysis. We present a patient with chronic renal failure, who was not on dialysis program yet, suffered from star fruit intoxication with presentation of consciousness disturbance and successfully managed by a session of hemodialysis.

  20. Nest success, cause-specific nest failure, and hatchability of aquatic birds at selenium-contaminated Kesterson Reservoir and a reference site

    USGS Publications Warehouse

    Ohlendorf, Harry M.; Hothem, Roger L.; Welsh, Daniel

    1989-01-01

    During 1983-1985, we studied the reproductive success of several species of aquatic birds (coots, ducks, shorebirds, and grebes) nesting at two sites in Merced County, California: a selenium-contaminated site (Kesterson Reservoir) and a nearby reference site (Volta Wildlife Area). We used a computer program (MICROMORT) developed for the analysis of radiotelemetry data (Heisey and Fuller 1985) to estimate nest success and cause-specific failure rates, and then compared these parameters and hatchability between sites and among years. Nest success and causes of failure varied by species, site, and year. The most important causes of nest failure were usually predation, desertion, and water-level changes. However, embryotoxicosis (mortality, deformity, and lack of embryonic development) was the most important cause of nest failure in Eared Grebes (Podiceps nigricollis) at Kesterson Reservoir. Embryotoxicosis also reduced the hatchability of eggs of all other species at Kesterson in one or more years; embryonic mortality occurred rarely at Volta, and abnormalities were not observed.

  1. High Israeli mortality rates from diabetes and renal failure - Can international comparison of multiple causes of death reflect differences in choice of underlying cause?

    PubMed

    Goldberger, Nehama; Applbaum, Yael; Meron, Jill; Haklai, Ziona

    2015-01-01

    The age-adjusted mortality rate in Israel is low compared to most Western countries although mortality rates from diabetes and renal failure in Israel are amongst the highest, while those from cardiovascular diseases (CVD) are amongst the lowest. This study aims to assess validity of choice of underlying causes (UC) in Israel by analyzing Israeli and international data on the prevalence of these diseases as multiple causes of death (MCOD) compared to UC, and data on comorbidity (MCOD based). Age-adjusted death rates were calculated for UC and MCOD and the corresponding ratio of multiple to underlying cause of death (SRMU) for available years between 1999 and 2012. Comorbidity was explored by calculating cause of death association indicators (CDAI) and frequency of comorbid disease. These results were compared to data from USA, France, Italy, Australia and the Czech Republic for 2009 or other available year. Mortality rates for all these diseases except renal failure have decreased in Israel between 1999 and 2012 as UC and MCOD. In 2009, the SRMU for diabetes was 2.7, slightly lower than other Western countries (3.0-3.5) showing more frequent choice as UC. Similar results were found for renal failure. In contrast, the SRMU for ischemic heart disease (IHD) and cerebrovascular disease were 2.0 and 2.6, respectively, higher than other countries (1.4-1.6 and 1.7-1.9, respectively), showing less frequent choice as UC. CDAI data showed a strong association between heart and cerebrovascular disease, and diabetes in all countries. In Israel, 40 % of deaths with UC diabetes had IHD and 24 % had cerebrovascular disease. Renal disease was less strongly associated with IHD. This international comparison suggests that diabetes and renal failure may be coded more frequently in Israel as UC, sometimes instead of heart and cerebrovascular disease. Even with some changes in coding, mortality rates would be high compared to other countries, similar to the comparatively high

  2. [Heart failure patterns in Djibouti: epidemiologic transition].

    PubMed

    Massoure, P L; Roche, N C; Lamblin, G; Topin, F; Dehan, C; Kaiser, E; Fourcade, L

    2013-05-01

    The features of heart failure (HF) in Djibouti have not been well described. We sought to document the current patterns of HF here. We prospectively included Djiboutian adults hospitalized for HF in the French Military Hospital (Djibouti) from August 2008 through December 2010. Of 1688 adults hospitalized in the medical department, 45 (2.7%) had symptomatic HF: 38 (84%) men, mean age 55.8 years (range 27-75). Twenty-five (56%) patients were initially hospitalized for acute pulmonary edema. The underlying diseases included coronary artery disease (CAD) (62%), hypertensive heart disease (18%), rheumatic valvular disease (13%), and primary dilated cardiomyopathy (7%). Their cardiovascular risk factors included tobacco use (53%), hypertension (69%), diabetes (47%), and hypercholesterolemia (51%). Patients in the CAD group were older, and had diabetes more often (p<0.01). All khat chewers (53%) were males and smokers. Mean left ventricular ejection fraction (LVEF) was 39 ± 14%. During follow-up (14.4 ± 9 months), 8 (18%) patients died, 9 (20%) were again hospitalized for HF, and 3 (7%) had ischemic strokes. One month after discharge, the New York Heart Association (NYHA) class was II for 40%, III for 44%, and IV for 16%. Higher NYHA classes and dilated cardiomyopathy were both associated with poorer outcomes (p<0.03). In hospitalized Djiboutians, most HF patterns are similar to those in industrialized countries. CAD is more prevalent than previously reported in African patients with HF.

  3. Why do organizations not learn from incidents? Bottlenecks, causes and conditions for a failure to effectively learn.

    PubMed

    Drupsteen, Linda; Hasle, Peter

    2014-11-01

    If organizations would be able to learn more effectively from incidents that occurred in the past, future incidents and consequential injury or damage can be prevented. To improve learning from incidents, this study aimed to identify limiting factors, i.e. the causes of the failure to effectively learn. In seven organizations focus groups were held to discuss factors that according to employees contributed to the failure to learn. By use of a model of the learning from incidents process, the steps, where difficulties for learning arose, became visible, and the causes for these difficulties could be studied. Difficulties were identified in multiple steps of the learning process, but most difficulties became visible when planning actions, which is the phase that bridges the gap from incident investigation to actions for improvement. The main causes for learning difficulties, which were identified by the participants in this study, were tightly related to the learning process, but some indirect causes - or conditions - such as lack of ownership and limitations in expertise were also mentioned. The results illustrate that there are two types of causes for the failure to effectively learn: direct causes and indirect causes, here called conditions. By actively and systematically studying learning, more conditions might be identified and indicators for a successful learning process may be determined. Studying the learning process does, however, require a shift from learning from incidents to learning to learn. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Primary Hyperoxaluria Type 1: A Cause for Infantile Renal Failure and Massive Nephrocalcinosis.

    PubMed

    Kurt-Sukur, E D; Özçakar, Z B; Fitöz, S; Yilmaz, S; Hoppe, B; Yalçinkaya, F

    2015-09-01

    Primary hyperoxaluria type 1 is a rare autosomal-recessive disease caused by the deficient activity of the liver specific enzyme alanine-glyoxylate aminotransferase. Increased endogenous oxalate production induces severe hyperoxaluria, recurrent urolithiasis, progressive nephrocalcinosis and renal failure. Here we report a 6 month old boy who presented with vomiting and decreased urine volume. He was diagnosed with chronic kidney failure at 4 months of age and peritoneal dialysis was introduced at a local hospital. His parents were third degree cousins and family history revealed 2 maternal cousins who developed end stage renal disease during childhood. When he was admitted to our hospital, laboratory studies were consistent with end stage renal disease, ultrasound showed bilateral massive nephrocalcinosis. As clinical presentation was suggestive for primary hyperoxaluria type 1, plasma oxalate was determined and found extremely elevated. Genetic testing proved diagnosis by showing a disease causing homozygous mutation (AGXT-gene: c.971_972delT). The patient was put on pyridoxine treatment and aggressive dialysis programme. In conclusion; progressive renal failure in infancy with massive nephrocalcinosis, especially if accompanied by consanguinity and family history, should always raise the suspicion of PH type 1. Increased awareness of the disease would help physicians in both treating the patients and guiding the families who have diseased children and plan to have further pregnancies. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Self-Care and All-Cause Mortality in Patients With Chronic Heart Failure.

    PubMed

    Kessing, Dionne; Denollet, Johan; Widdershoven, Jos; Kupper, Nina

    2016-03-01

    This study examined the association of self-care with all-cause mortality in a cohort of patients with chronic heart failure (HF). Although self-care is crucial to maintain health in patients with chronic HF, studies examining an association with clinical outcomes are scarce. Consecutive patients with chronic HF (n = 559, mean age 66.3 ± 9.5 years, 78% men) completed the 9-item European Heart Failure Self-care Behaviour scale. Our endpoint was all-cause mortality. Associations between self-care and all-cause mortality were assessed with Kaplan-Meier analyses and multivariable Cox regression accounting for standard sociodemographic and clinical covariates, psychological distress, and self-rated health. After a median follow-up of 5.5 ± 2.4 years (range 16 weeks to 9.9 years), 221 deaths (40%) from any cause were recorded. There was no evidence of a mortality benefit in patients high over those low in global self-care (p = 0.71). In post hoc analyses, low self-reported sodium intake was associated with increased mortality (adjusted hazard ratio: 1.47; 95% confidence interval: 1.10 to 1.96; p = 0.01). Other significant predictors of mortality were: male sex, lack of a partner, New York Heart Association functional class III to IV, and increasing comorbid conditions. Global self-care was not associated with long-term mortality whereas low self-reported sodium intake independently predicted increased all-cause mortality beyond parameters of disease severity. Replication of findings is needed as well as studies examining the correspondence of subjectively and objectively measured sodium intake and its effects on long-term prognosis in patients with chronic HF. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  6. Detailed investigation of causes of avionics field failures

    NASA Astrophysics Data System (ADS)

    Kallis, J. M.; Buechler, D. W.; Richardson, Z. C.; Backes, P. G.; Lopez, S. B.; Erickson, J. J.; van Westerhuyzen, D. H.

    A detailed analysis of digital and analog modules from the F-15 AN/APG-63 Radar was performed to identify the kinds, types, and number of life models based on observed failure modes, mechanisms, locations, and characteristics needed to perform a Failure Free Operating Period prediction for these items. It is found that a significant fraction of the failures of the analog module and a small fraction of those of the digital module resulted from the exacerbation of latent defects by environmental stresses. It is also found that the fraction of failures resulting from thermal cycling and vibration is small.

  7. Radiation necrosis causing failure of automatic ventilation during sleep with central sleep apnea

    SciTech Connect

    Udwadia, Z.F.; Athale, S.; Misra, V.P.

    A patient operated upon for a midline cerebellar hemangioblastoma developed failure of automatic respiration during sleep, together with central sleep apnea syndrome, approximately two years after receiving radiation therapy to the brain. Clinical and CT scan findings were compatible with a diagnosis of radiation necrosis as the cause of his abnormal respiratory control.

  8. NASA's Evolutionary Xenon Thruster (NEXT) Power Processing Unit (PPU) Capacitor Failure Root Cause Analysis

    NASA Technical Reports Server (NTRS)

    Soeder, James F.; Pinero, Luis; Schneidegger, Robert; Dunning, John; Birchenough, Art

    2012-01-01

    The NASA's Evolutionary Xenon Thruster (NEXT) project is developing an advanced ion propulsion system for future NASA missions for solar system exploration. A critical element of the propulsion system is the Power Processing Unit (PPU) which supplies regulated power to the key components of the thruster. The PPU contains six different power supplies including the beam, discharge, discharge heater, neutralizer, neutralizer heater, and accelerator supplies. The beam supply is the largest and processes up to 93+% of the power. The NEXT PPU had been operated for approximately 200+ hours and has experienced a series of three capacitor failures in the beam supply. The capacitors are in the same, nominally non-critical location the input filter capacitor to a full wave switching inverter. The three failures occurred after about 20, 30, and 135 hours of operation. This paper provides background on the NEXT PPU and the capacitor failures. It discusses the failure investigation approach, the beam supply power switching topology and its operating modes, capacitor characteristics and circuit testing. Finally, it identifies root cause of the failures to be the unusual confluence of circuit switching frequency, the physical layout of the power circuits, and the characteristics of the capacitor.

  9. NASA's Evolutionary Xenon Thruster (NEXT) Power Processing Unit (PPU) Capacitor Failure Root Cause Analysis

    NASA Technical Reports Server (NTRS)

    Soeder, James F.; Scheidegger, Robert J.; Pinero, Luis R.; Birchenough, Arthur J.; Dunning, John W.

    2012-01-01

    The NASA s Evolutionary Xenon Thruster (NEXT) project is developing an advanced ion propulsion system for future NASA missions for solar system exploration. A critical element of the propulsion system is the Power Processing Unit (PPU) which supplies regulated power to the key components of the thruster. The PPU contains six different power supplies including the beam, discharge, discharge heater, neutralizer, neutralizer heater, and accelerator supplies. The beam supply is the largest and processes up to 93+% of the power. The NEXT PPU had been operated for approximately 200+ hr and has experienced a series of three capacitor failures in the beam supply. The capacitors are in the same, nominally non-critical location-the input filter capacitor to a full wave switching inverter. The three failures occurred after about 20, 30, and 135 hr of operation. This paper provides background on the NEXT PPU and the capacitor failures. It discusses the failure investigation approach, the beam supply power switching topology and its operating modes, capacitor characteristics and circuit testing. Finally, it identifies root cause of the failures to be the unusual confluence of circuit switching frequency, the physical layout of the power circuits, and the characteristics of the capacitor.

  10. Evidence that failure of osteoid bone matrix resorption is caused by perturbation of osteoclast polarization.

    PubMed

    Yovich, S; Seydel, U; Papadimitriou, J M; Nicholson, G C; Wood, D J; Zheng, M H

    1998-04-01

    Osteoclasts resorb bone by a complex dynamic process that initially involves attachment, polarization and enzyme secretion, followed by their detachment and migration to new sites. In this study, we postulated that mineralized and osteoid bone matrix signal osteoclasts differently, resulting in the resorption of mineralized bone matrix only. We, therefore, compared the cytoplasmic distribution of cytoskeletal proteins F-actin and vinculin using confocal laser-scanning microscopy in osteoclasts cultured on mineralized and demineralized bone slices and correlated the observations with their functional activity. Our results have demonstrated significant differences in F-actin and vinculin staining patterns between osteoclasts cultured on mineralized bone matrix and those on demineralized bone matrix. In addition, the structural variations were accompanied by significant differences in bone resorbing activity between osteoclasts grown on mineralized bone matrix and those on demineralized bone matrix after 24 h of culture --resorption only occurring in mineralized bone but not in demineralized bone. These results indicated that failure of osteoid bone resorption is caused by perturbation of osteoclast polarization.

  11. Chaos emerging in soil failure patterns observed during tillage: Normalized deterministic nonlinear prediction (NDNP) and its application.

    PubMed

    Sakai, Kenshi; Upadhyaya, Shrinivasa K; Andrade-Sanchez, Pedro; Sviridova, Nina V

    2017-03-01

    Real-world processes are often combinations of deterministic and stochastic processes. Soil failure observed during farm tillage is one example of this phenomenon. In this paper, we investigated the nonlinear features of soil failure patterns in a farm tillage process. We demonstrate emerging determinism in soil failure patterns from stochastic processes under specific soil conditions. We normalized the deterministic nonlinear prediction considering autocorrelation and propose it as a robust way of extracting a nonlinear dynamical system from noise contaminated motion. Soil is a typical granular material. The results obtained here are expected to be applicable to granular materials in general. From a global scale to nano scale, the granular material is featured in seismology, geotechnology, soil mechanics, and particle technology. The results and discussions presented here are applicable in these wide research areas. The proposed method and our findings are useful with respect to the application of nonlinear dynamics to investigate complex motions generated from granular materials.

  12. Analysis of rural intersection accidents caused by stop sign violation and failure to yield the right-of-way

    DOT National Transportation Integrated Search

    2000-09-01

    The objectives of this study were to (1) identify the factors that contribute to accidents caused by failure to stop and failure to yield the right-of-way at rural two-way stop-controlled intersections on the state highway system, and (2) determine w...

  13. Familial mixed nephrocalcinosis as a cause of chronic kidney failure: two case reports.

    PubMed

    de Arruda, Pedro Francisco Ferraz; Gatti, Márcio; de Arruda, José Germano Ferraz; Fácio, Fernando Nestor; Spessoto, Luis Cesar Fava; de Arruda, Laísa Ferraz; de Godoy, José Maria Pereira; Godoy, Moacir Fernandes

    2014-10-27

    Nephrocalcinosis consists of the deposition of calcium salts in the renal parenchyma and is considered the mixed form when it involves the renal cortex and medulla. The main etiological agents of this condition are primary hyperparathyroidism, renal tubular acidosis, medullary sponge kidney, hyperoxaluria and taking certain drugs. These factors can lead to hypercalcemia and/or hypercalciuria, which can give rise to nephrocalcinosis. Patient 1 was a 48-year-old Caucasian woman with a history of bilateral nephrocalcinosis causing chronic kidney failure. Imaging examinations (X-ray, ultrasound and computed tomography of the abdomen) revealed extensive calcium deposits in the renal parenchyma, indicating nephrocalcinosis as the causal factor of the disease. Patient 2 is the 45-year-old brother of patient 1. He exhibited an advanced stage of chronic kidney failure. As nephrocalcinosis is considered to have a genetic component, a family investigation revealed this condition in patient 2. Nephrocalcinosis may be detected incidentally through diagnostic imaging studies. Whenever possible, treatment should include the base disease that caused the appearance of the calcification, as the precise etiological determination is extremely important.

  14. Drugs That May Cause or Exacerbate Heart Failure: A Scientific Statement From the American Heart Association.

    PubMed

    Page, Robert L; O'Bryant, Cindy L; Cheng, Davy; Dow, Tristan J; Ky, Bonnie; Stein, C Michael; Spencer, Anne P; Trupp, Robin J; Lindenfeld, JoAnn

    2016-08-09

    Heart failure is a common, costly, and debilitating syndrome that is associated with a highly complex drug regimen, a large number of comorbidities, and a large and often disparate number of healthcare providers. All of these factors conspire to increase the risk of heart failure exacerbation by direct myocardial toxicity, drug-drug interactions, or both. This scientific statement is designed to serve as a comprehensive and accessible source of drugs that may cause or exacerbate heart failure to assist healthcare providers in improving the quality of care for these patients. © 2016 American Heart Association, Inc.

  15. Spatio-temporal patterns of bacteria caused by collective motion

    NASA Astrophysics Data System (ADS)

    Kitsunezaki, So

    2006-04-01

    In incubation experiments on bacterial colonies of Proteus mirabilis, collective motion of bacteria is found to generate macroscopic turbulent patterns on the surface of agar media. We propose a mathematical model to describe the time evolution of the positional and directional distributions of motile bacteria in such systems, and investigate this model both numerically and analytically. It is shown that as the average density of bacteria increases, nonuniform swarming patterns emerge from a uniform stationary state. For a sufficient large density, we find that spiral patterns are caused by interactions between the local bacteria densities and the rotational mode of the collective motion. Unidirectional spiral patterns similar to those observed in experiments appear in the case in which the equilibrium directional distribution is asymmetric.

  16. Random safety auditing, root cause analysis, failure mode and effects analysis.

    PubMed

    Ursprung, Robert; Gray, James

    2010-03-01

    Improving quality and safety in health care is a major concern for health care providers, the general public, and policy makers. Errors and quality issues are leading causes of morbidity and mortality across the health care industry. There is evidence that patients in the neonatal intensive care unit (NICU) are at high risk for serious medical errors. To facilitate compliance with safe practices, many institutions have established quality-assurance monitoring procedures. Three techniques that have been found useful in the health care setting are failure mode and effects analysis, root cause analysis, and random safety auditing. When used together, these techniques are effective tools for system analysis and redesign focused on providing safe delivery of care in the complex NICU system. Copyright 2010 Elsevier Inc. All rights reserved.

  17. Failure of azithromycin 2.0 g in the treatment of gonococcal urethritis caused by high-level resistance in California.

    PubMed

    Gose, Severin O; Soge, Olusegun O; Beebe, James L; Nguyen, Duylinh; Stoltey, Juliet E; Bauer, Heidi M

    2015-05-01

    We report a treatment failure to azithromycin 2.0 g caused by a urethral Neisseria gonorrhoeae isolate with high-level azithromycin resistance in California. This report describes the epidemiological case investigation and phenotypic and genetic characterization of the treatment failure isolate.

  18. Patterns of Failure After Concurrent Bevacizumab and Hypofractionated Stereotactic Radiation Therapy for Recurrent High-Grade Glioma

    SciTech Connect

    Shapiro, Lauren Q.; Beal, Kathryn, E-mail: bealk@mskcc.org; Goenka, Anuj

    2013-03-01

    Purpose: Concurrent bevacizumab with hypofractionated stereotactic radiation therapy (HSRT) is safe and effective for the treatment of recurrent high-grade gliomas (HGG). The objective of this study was to characterize the patterns of failure after this treatment regimen. Methods and Materials: Twenty-four patients with recurrent enhancing HGG were previously treated on an institutional review board-approved protocol of concurrent bevacizumab and reirradiation. Patients received 30 Gy in 5 fractions to the recurrent tumor with HSRT. Brain magnetic resonance imaging (MRI) was performed every 2 cycles, and bevacizumab was continued until clinical or radiographic tumor progression according to the criteria of Macdonald etmore » al. MRI at the time of progression was fused to the HSRT treatment plan, and the location of recurrence was classified on the basis of volume within the 95% isodose line. Outcomes based on patient characteristics, tumor grade, recurrence pattern, and best response to treatment were analyzed by the Kaplan-Meier method. Results: Twenty-two patients experienced either clinical or radiographic progression. Recurrent tumor was enhancing in 15 (71.4%) and nonenhancing in 6 (28.6%) patients. Eleven patients (52.4%) had recurrence within the radiation field, 5 patients (23.8%) had marginal recurrence, and 5 patients had recurrence outside the radiation field. Pattern of enhancement and location of failure did not correlate with overall survival or progression-free survival. Radiographic response was the only variable to significantly correlate with progression-free survival. Conclusions: Despite the promising initial response seen with the addition of HSRT to bevacizumab as salvage treatment for recurrent HGG, approximately half of patients ultimately still experience failure within the radiation field. The rate of local failure with the addition of HSRT seems to be lower than that seen with bevacizumab alone in the salvage setting. Our data

  19. Clinical Courses of Graft Failure Caused by Chronic Allograft Dysfunction in Kidney Transplantation.

    PubMed

    Fujiwara, T; Teruta, S; Tsudaka, S; Ota, K; Matsuda, H

    Chronic allograft dysfunction (CAD) is a main cause of graft failure in kidney transplantation. We retrospectively analyzed 279 kidney transplant recipients who survived with a functioning graft for at least 2 years. CAD was defined as chronic graft deterioration, excluding other specific causes. We defined the pattern of decline in estimated glomerular filtration rate (eGFR), as follows: (1) "plateau" was defined as decline in eGFR ≤2 mL/min/1.73 m 2 /year; "long plateaus" were those lasting more than 5 years; (2) "rapid decline" was a decrease in eGFR ≥20 mL/min/1.73 m 2 /year. Patients diagnosed with CAD were categorized according to the occurrence of rapid decline and/or long plateau as follows: group 1, neither rapid decline nor long plateau; group 2, rapid decline only; group 3, long plateau only; and group 4, both rapid decline and long plateau. From a total of 81 graft losses, 51 (63%) failed because of CAD, with a median of 9.4 years. Sixteen patients belonged to group 1, 14 to group 2, 12 to group 3, and nine to group 4. Mean graft survival times in the four groups were 7.7 ± 1.1, 6.1 ± 3.1, 16.2 ± 2.5, and 10.8 ± 3.6 years, respectively (P < .001). There were significant differences among groups in donor age, year of transplantation, mean eGFR at baseline, and acute rejection rate after transplantation. The results indicate that this cohort of kidney transplant recipients who had CAD comprised subgroups with different clinical courses. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. What causes the patterns of gypsy moth defoliation?

    Treesearch

    Clive G. Jones

    1991-01-01

    Gypsy moth defoliation is typically observed to occur on xeric ridge tops before more mesic, lowland forest, in oak-dominated habitats in the Northeast. In subsequent years defoliation may also occur in mesic forests. What causes this pattern of defoliation? Differences in the degree of defoliation may be due to differences in the density of gypsy moth populations in...

  1. Electrophysiological diagnosis and patterns of response to treatment of botulism with neuromuscular respiratory failure.

    PubMed

    Kongsaengdao, Subsai; Samintarapanya, Kanoksri; Rusmeechan, Siwarit; Sithinamsuwan, Pasiri; Tanprawate, Surat

    2009-08-01

    In this study we describe the electrophysiological findings in botulism patients with neuromuscular respiratory failure from major botulism outbreaks in Thailand. High-rate repetitive nerve stimulation testing (RNST) of the abductor digiti minimi (ADM) muscle of 17 botulism patients with neuromuscular respiratory failure showed mostly incremental responses, especially in response to >20-HZ stimulation. In the most severe stage of neuromuscular respiratory failure, RNST failed to elicit a compound muscle action potential (CMAP) of the ADM muscle. In the moderately severe stage, the initial CMAPs were of very low amplitude, and a 3-HZ RNST elicited incremental or decremental responses. A 10-HZ RNST elicited mainly decremental responses. In the early recovery stage, the initial CMAP amplitudes of the ADM muscle improved, with initially low amplitudes and an incremental response to 3- and 10-HZ RNSTs. Improved electrophysiological patterns of the ADM muscle correlated with improved respiratory muscle function. Incremental responses to 20-HZ RNST were most useful for diagnosis. The initial electrodiagnostic sign of recovery following treatment of neuromuscular respiratory failure was an increased CMAP amplitude and an incremental response to 10-20-HZ RNST. Muscle Nerve 40: 271-278, 2009.

  2. Cerebellar medulloblastoma: the importance of posterior fossa dose to survival and patterns of failure

    SciTech Connect

    Silverman, C.L.; Simpson, J.R.

    1982-11-01

    Fifty patients with biopsy-proven cerebellar medulloblastoma were retrospectively analyzed for prognostic factors, survival and patterns of failure. Five- and ten-year actuarial survivals for the entire group were 51% and 42%. Survival and local control were significantly better for the 21 patients who received doses greater than 5000 rad to the posterior fossa (85% and 80% respectively) than for the remaining patients (38% and 38%, respectively). Significant prognostic factors included achievement of local control in the posterior fossa (p = .0001) and dose to the posterior fossa (p = .0005). Sex, age, duration of symptoms, extent of surgery and initial T-stagemore » of disease were not significant. Posterior fossa was the predominant site of failure (71% of failures), but 10% of patients failed in the cerebrum and 12% outside the CNS. This experience confirms that survival rates of 70-80% are achievable with current treatment policies but accurate and consistent dose delivery to the posterior fossa is essential.« less

  3. Cerebellar medulloblastoma: the importance of posterior fossa dose to survival and patterns of failure

    SciTech Connect

    Silverman, C.L.; Simpson, J.R.

    1982-11-01

    Fifty patients with biopsy-proven cerebellar medulloblastoma were retrospectively analyzed for prognostic factors, survival and patterns of failure. Five- and ten-year actuarial survivals for the entire group were 51% and 42%. Survival and local control were significantly better for the 21 patients who received doses greater that 5000 rad to the posterior fossa (85% and 80% respectively) than for the remaining patients (38% and 38%, respectively). Significant prognostic factors included achievement of local control in the posterior fossa (p = .0001) and dose to the posterior fossa (p = .0005). Sex, age, duration of symptoms, extent of surgery and initial T-stagemore » of disease were not significant. Posterior fossa was the predominant site of failure (71% of failures), but 10% of patients failed in the cerebrum and 12% outside the CNS. This experience confirms that survival rates of 70-80% are achievable with current treatment policies but accurate and consistent dose delivery to the posterior fossa is essential.« less

  4. Risk-based decision making to manage water quality failures caused by combined sewer overflows

    NASA Astrophysics Data System (ADS)

    Sriwastava, A. K.; Torres-Matallana, J. A.; Tait, S.; Schellart, A.

    2017-12-01

    Regulatory authorities set certain environmental permit for water utilities such that the combined sewer overflows (CSO) managed by these companies conform to the regulations. These utility companies face the risk of paying penalty or negative publicity in case they breach the environmental permit. These risks can be addressed by designing appropriate solutions such as investing in additional infrastructure which improve the system capacity and reduce the impact of CSO spills. The performance of these solutions is often estimated using urban drainage models. Hence, any uncertainty in these models can have a significant effect on the decision making process. This study outlines a risk-based decision making approach to address water quality failure caused by CSO spills. A calibrated lumped urban drainage model is used to simulate CSO spill quality in Haute-Sûre catchment in Luxembourg. Uncertainty in rainfall and model parameters is propagated through Monte Carlo simulations to quantify uncertainty in the concentration of ammonia in the CSO spill. A combination of decision alternatives such as the construction of a storage tank at the CSO and the reduction in the flow contribution of catchment surfaces are selected as planning measures to avoid the water quality failure. Failure is defined as exceedance of a concentration-duration based threshold based on Austrian emission standards for ammonia (De Toffol, 2006) with a certain frequency. For each decision alternative, uncertainty quantification results into a probability distribution of the number of annual CSO spill events which exceed the threshold. For each alternative, a buffered failure probability as defined in Rockafellar & Royset (2010), is estimated. Buffered failure probability (pbf) is a conservative estimate of failure probability (pf), however, unlike failure probability, it includes information about the upper tail of the distribution. A pareto-optimal set of solutions is obtained by performing mean

  5. Impaired working memory capacity is not caused by failures of selective attention in schizophrenia.

    PubMed

    Erickson, Molly A; Hahn, Britta; Leonard, Carly J; Robinson, Benjamin; Gray, Brad; Luck, Steven J; Gold, James

    2015-03-01

    The cognitive impairments associated with schizophrenia have long been known to involve deficits in working memory (WM) capacity. To date, however, the causes of WM capacity deficits remain unknown. The present study examined selective attention impairments as a putative contributor to observed capacity deficits in this population. To test this hypothesis, we used an experimental paradigm that assesses the role of selective attention in WM encoding and has been shown to involve the prefrontal cortex and the basal ganglia. In experiment 1, participants were required to remember the locations of 3 or 5 target items (red circles). In another condition, 3-target items were accompanied by 2 distractor items (yellow circles), which participants were instructed to ignore. People with schizophrenia (PSZ) exhibited significant impairment in memory for the locations of target items, consistent with reduced WM capacity, but PSZ and healthy control subjects did not differ in their ability to filter the distractors. This pattern was replicated in experiment 2 for distractors that were more salient. Taken together, these results demonstrate that reduced WM capacity in PSZ is not attributable to a failure of filtering irrelevant distractors. © The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  6. Modelling of a Francis Turbine Runner Fatigue Failure Process Caused by Fluid-Structure Interaction

    NASA Astrophysics Data System (ADS)

    Lyutov, A.; Kryukov, A.; Cherny, S.; Chirkov, D.; Salienko, A.; Skorospelov, V.; Turuk, P.

    2016-11-01

    In the present paper considered is the problem of the numerical simulation of Francis turbine runner fatigue failure caused by fluid-structure interaction. The unsteady 3D flow is modeled simultaneously in the spiral chamber, each wicket gate and runner channels and in the draft tube using the Euler equations. Based on the unsteady runner loadings at each time step stresses in the whole runner are calculated using the elastic equilibrium equations solved with boundary element method. Set of static stress-strain states provides quasi-dynamics of runner cyclic loading. It is assumed that equivalent stresses in the runner are below the critical value after which irreversible plastic processes happen in the runner material. Therefore runner is subjected to the fatigue damage caused by high-cycle fatigue, in which the loads are generally low compared with the limit stress of the material. As a consequence, the stress state around the crack front can be fully characterized by linear elastic fracture mechanics. The place of runner cracking is determined as a point with maximal amplitude of stress oscillations. Stress pulsations amplitude is used to estimate the number of cycles until the moment of fatigue failure, number of loading cycles and oscillation frequency are used to calculate runner service time. Example of the real Francis runner which has encountered premature fatigue failure as a result of incorrect durability estimation is used to verify the developed numerical model.

  7. Failure Rates and Patterns of Recurrence in Patients With Resected N1 Non-Small-Cell Lung Cancer

    SciTech Connect

    Varlotto, John M., E-mail: jvarlotto@hmc.psu.edu; Medford-Davis, Laura Nyshel; Recht, Abram

    2011-10-01

    Purpose: To examine the local and distant recurrence rates and patterns of failure in patients undergoing potentially curative resection of N1 non-small-cell lung cancer. Methods and Materials: The study included 60 consecutive unirradiated patients treated from 2000 to 2006. Median follow-up was 30 months. Failure rates were calculated by the Kaplan-Meier method. A univariate Cox proportional hazard model was used to assess factors associated with recurrence. Results: Local and distant failure rates (as the first site of failure) at 2, 3, and 5 years were 33%, 33%, and 46%; and 26%, 26%, and 32%, respectively. The most common site ofmore » local failure was in the mediastinum; 12 of 18 local recurrences would have been included within proposed postoperative radiotherapy fields. Patients who received chemotherapy were found to be at increased risk of local failure, whereas those who underwent pneumonectomy or who had more positive nodes had significantly increased risks of distant failure. Conclusions: Patients with resected non-small-cell lung cancer who have N1 disease are at substantial risk of local recurrence as the first site of relapse, which is greater than the risk of distant failure. The role of postoperative radiotherapy in such patients should be revisited in the era of adjuvant chemotherapy.« less

  8. Respiratory Failure

    MedlinePlus

    ... of oxygen in the blood, it's called hypoxemic (HI-pok-SE-mik) respiratory failure. When respiratory failure ... carbon dioxide in the blood, it's called hypercapnic (HI-per-KAP-nik) respiratory failure. Causes Diseases and ...

  9. [Chronic heart failure].

    PubMed

    Gosch, Markus

    2008-08-01

    As a consequence of the increasing life expectancy the number of patients suffering from chronic heart failure has been growing continuously in the past few decades, especially in the group of the old and oldest. Frailty is a clinical syndrome that geriatricians attach great importance to. Like many other diseases chronic heart failure can cause frailty. Based on the experience that we see only a small correlation between the functional capacity of patients with heart failure and the results of cardiological findings, the model of peripheral myopathy in chronic heart failure was developed. Different pathophysiological changes may cause the increasing exercise intolerance in patients with chronic heart failure. We can already consider different experimental approaches to the therapy of frailty caused by chronic heart failure. At the moment we have to focus our efforts on an optimal therapy of heart failure, especially with angiotensin-converting-enzyme inhibitors and beta-blockers, and on individual endurance and strength training.

  10. Mitigation of Manhole Events Caused by Secondary Cable Failure

    NASA Astrophysics Data System (ADS)

    Zhang, Lili

    "Manhole event" refers to a range of phenomena, such as smokers, fires and explosions which occur on underground electrical infrastructure, primarily in major cities. The most common cause of manhole events is decomposition of secondary cable initiated by an electric fault. The work presented in this thesis addresses various aspects related to the evolution and mitigation of the manhole events caused by secondary cable insulation failure. Manhole events develop as a result of thermal decomposition of organic materials present in the cable duct and manholes. Polymer characterization techniques are applied to intensively study the materials properties as related to manhole events, mainly the thermal decomposition behaviors of the polymers present in the cable duct. Though evolved gas analysis, the combustible gases have been quantitatively identified. Based on analysis and knowledge of field conditions, manhole events is divided into at least two classes, those in which exothermic chemical reactions dominate and those in which electrical energy dominates. The more common form of manhole event is driven by air flow down the duct. Numerical modeling of smolder propagation in the cable duct demonstrated that limiting air flow is effective in reducing the generation rate of combustible gas, in other words, limiting manhole events to relatively minor "smokers". Besides manhole events, another by-product of secondary cable insulation breakdown is stray voltage. The danger to personnel due to stray voltage is mostly caused by the 'step potential'. The amplitude of step potential as a result of various types of insulation defects is calculated using Finite Element Analysis (FEA) program.

  11. Hypokalemic muscular paralysis causing acute respiratory failure due to rhabdomyolysis with renal tubular acidosis in a chronic glue sniffer.

    PubMed

    Kao, K C; Tsai, Y H; Lin, M C; Huang, C C; Tsao, C Y; Chen, Y C

    2000-01-01

    A 34-year-old male was admitted to the emergency department with the development of quadriparesis and respiratory failure due to hypokalemia after prolonged glue sniffing. The patient was subsequently given mechanical ventilatory support for respiratory failure. He was weaned from the ventilator 4 days later after potassium replacement. Toluene is an aromatic hydrocarbon found in glues, cements, and solvents. It is known to be toxic to the nervous system, hematopoietic system, and causes acid-base and electrolyte disorders. Acute respiratory failure with hypokalemia and rhabdomyolysis with acute renal failure should be considered as potential events in a protracted glue sniffing.

  12. Incidence, causes and consequences of pregnancy failure in viviparous lizards: implications for research and conservation settings.

    PubMed

    Hare, Kelly M; Cree, Alison

    2010-01-01

    Research on the causes of pregnancy failure in vertebrates has historically been mammal-focussed. However, live-birth (viviparity) has evolved multiple times, and is present in all other vertebrate taxa except Aves and Agnatha. Viviparous lizards (O. Squamata, excluding snakes and amphisbaenians) provide a valuable experimental group when studying major evolutionary events and some are also species of high conservation value. Consequently, both researchers and herpetoculturists often require high reproductive output from captive-held lizards. We reviewed the literature to determine potential or known causes of pregnancy failure for captive lizards. Pregnancy success across species averages approximately 86%, but varies extensively and does not appear to be related to embryonic stage when brought into captivity or level of placentation. Causes of pregnancy failure also vary among species, but correct thermal environments are vital to success, and providing adequate nutrition before vitellogenesis increases the number of viable offspring. A coordinated sequence of hormonal changes involving both pro-pregnancy and pro-labour factors is important for successful pregnancies, although uncertainty remains around the maternal concentrations of corticosterone that allow successful development. Several research areas commonly studied in mammals have yet to be explored or fully addressed in pregnant lizards, including impacts of toxins, parasites, UV light and nutritional quality. As viviparity has evolved over 100 times in lizards, and many different levels of placentation exist, pregnant lizards provide valuable models for studies in ecology and evolution and offer a useful comparison for studies on other viviparous vertebrates.

  13. Acute liver failure caused by hepatitis E virus genotype 3 and 4: A systematic review and pooled analysis.

    PubMed

    Haffar, Samir; Shalimar; Kaur, Ravinder J; Wang, Zhen; Prokop, Larry J; Murad, Mohammad H; Bazerbachi, Fateh

    2018-04-19

    Acute liver failure caused by hepatitis E virus genotype 3 and 4 has been rarely described. Because of the presence of a short golden therapeutic window in patients with viral acute liver failure from other causes, it is possible that early recognition and treatment might reduce the morbidity and mortality. We performed a systematic review and pooled analysis of acute liver failure caused by hepatitis E virus genotype 3 and 4. Two reviewers appraised studies after searching multiple databases on June 12th, 2017. Appropriate tests were used to compare hepatitis E virus genotype 3 vs 4, suspected vs confirmed genotypes, hepatitis E virus-RNA positive vs negative, and to discern important mortality risk factors. We identified 65 patients, with median age 58 years (range: 3-79), and a male to female ratio of 1.2:1. The median bilirubin, ALT, AST and alkaline phosphatase (expressed by multiplication of the upper limit of normal) levels were 14.8, 45.3, 34.8 and 1.63 respectively. Antihepatitis E virus IgG, antihepatitis E virus IgM and hepatitis E virus-RNA were positive in 84%, 91% and 86% of patients respectively. The median interval from symptoms onset to acute liver failure was 23 days, and 16 patients underwent liver transplantation. Final outcome was reported in 58 patients and mortality was 46%. Age was a predictor of poor prognosis in multivariate analysis. No important differences were found between patients infected with genotype 3 vs 4, patients with confirmed vs suspected genotypes, or patients with positive vs negative RNA. Acute liver failure caused by hepatitis E virus genotype 3 and 4 is rare, similar between genotypes, occurs commonly in middle-aged/elderly patients and has a very high mortality. Age is predictive of poor prognosis in multivariate analysis. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. 76 FR 70768 - Common-Cause Failure Analysis in Event and Condition Assessment: Guidance and Research, Draft...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-15

    ... NUCLEAR REGULATORY COMMISSION [NRC-2011-0254] Common-Cause Failure Analysis in Event and Condition Assessment: Guidance and Research, Draft Report for Comment; Correction AGENCY: Nuclear Regulatory Commission. ACTION: Draft NUREG; request for comment; correction. SUMMARY: This document corrects a notice appearing...

  15. Urea-induced ROS cause endothelial dysfunction in chronic renal failure.

    PubMed

    D'Apolito, Maria; Du, Xueliang; Pisanelli, Daniela; Pettoello-Mantovani, Massimo; Campanozzi, Angelo; Giacco, Ferdinando; Maffione, Angela Bruna; Colia, Anna Laura; Brownlee, Michael; Giardino, Ida

    2015-04-01

    The pathogenic events responsible for accelerated atherosclerosis in patients with chronic renal failure (CRF) are poorly understood. Here we investigate the hypothesis that concentrations of urea associated with CRF and increased ROS production in adipocytes might also increase ROS production directly in arterial endothelial cells, causing the same pathophysiologic changes seen with hyperglycemia. Primary cultures of human aortic endothelial cells (HAEC) were exposed to 20mM urea for 48 h. C57BL/6J wild-type mice underwent 5/6 nephrectomy or a sham operation. Randomized groups of 5/6 nephrectomized mice and their controls were also injected i.p. with a SOD/catalase mimetic (MnTBAP) for 15 days starting immediately after the final surgical procedure. Urea at concentrations seen in CRF induced mitochondrial ROS production in cultured HAEC. Urea-induced ROS caused the activation of endothelial pro-inflammatory pathways through the inhibition of GAPDH, including increased protein kinase C isoforms activity, increased hexosamine pathway activity, and accumulation of intracellular AGEs (advanced glycation end products). Urea-induced ROS directly inactivated the anti-atherosclerosis enzyme PGI2 synthase and also caused ER stress. Normalization of mitochondrial ROS production prevented each of these effects of urea. In uremic mice, treatment with MnTBAP prevented aortic oxidative stress, PGI2 synthase activity reduction and increased expression of the pro-inflammatory proteins TNFα, IL-6, VCAM1, Endoglin, and MCP-1. Taken together, these data show that urea itself, at levels common in patients with CRF, causes endothelial dysfunction and activation of proatherogenic pathways. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  16. Patterns of Failure for Rhabdomyosarcoma of the Perineal and Perianal Region

    SciTech Connect

    Casey, Dana L.; Wexler, Leonard H.; LaQuaglia, Michael P.

    2014-05-01

    Purpose: To analyze prognostic factors and patterns of failure for rhabdomyosarcoma of the perineal and perianal region (PRMS), with an emphasis on radiation therapy for locoregional control. Methods and Materials: Detailed records of all 14 patients treated for PRMS at Memorial Sloan-Kettering Cancer Center between 1998 and 2012 were reviewed. The Kaplan-Meier method was used to assess the event-free survival (EFS) and overall survival (OS), and a competing-risks analysis was used to assess the cumulative incidence of local, regional, and distant failures. Results: Median age was 15.8 years (range, 1.1-31.9 years). High-risk features were identified: 9 of 14 patients (64%) had groupmore » 3 disease and 3 of 14 (21%) had group 4; 11 of 14 tumors (78%) were alveolar; 12 of 14 tumors (86%) were ≥5 cm; and 9 of 14 patients (64%) had involved lymph nodes (N1). Of those aged ≥10 years at diagnosis, 9 of 10 (90%) had alveolar histology, all had tumors ≥5 cm, and 8 of 10 (80%) presented with N1 disease. The rates of local, regional, and distant failure at 5 years were 17%, 31%, and 52%, respectively. Although 3 of the 4 patients with regional failure received nodal irradiation, only one of the nodal failures occurred in the radiation therapy field. The 5-year EFS was 33%, and OS was 39%. Age ≥10 years was associated with poor outcomes: EFS was 13% in patients aged ≥10 years, compared with 75% in those aged <10 years (P=.04); the OS was 13% in patients aged ≥10 years, compared with 100% in those aged <10 years (P=.04). Conclusions: Patients with PRMS, especially those aged ≥10 years, present with poor prognostic features and continue to have poor outcomes. Given the high incidence of regional node recurrence, we recommend prophylactic ilioinguinal lymph node irradiation for all patients aged ≥10 years. For children aged <10 years, nodal evaluation is essential to determine the role for lymph node irradiation.« less

  17. Patterns of failure and survival in patients with nasopharyngeal carcinoma treated with intensity-modulated radiation therapy in Saudi Arabia.

    PubMed

    Maklad, Ahmed Marzouk; Bayoumi, Yasser; Senosy Hassan, Mohamed Abdalazez; Elawadi, AbuSaleh A; AlHussain, Hussain; Elyamany, Ashraf; Aldhahri, Saleh F; Al-Qahtani, Khalid Hussain; AlQahtani, Mubarak; Tunio, Mutahir A

    2016-01-01

    We aimed to investigate the patterns of failure (locoregional and distant metastasis), associated factors, and treatment outcomes in nasopharyngeal carcinoma patients treated with intensity-modulated radiation therapy (IMRT) combined with chemotherapy. From April 2006 to December 2011, 68 nasopharyngeal carcinoma patients were treated with IMRT and chemotherapy at our hospital. Median radiation doses delivered to gross tumor volume and positive neck nodes were 66-70 Gy, 63 Gy to clinical target volume, and 50.4-56 Gy to clinically negative neck. The clinical toxicities, patterns of failures, locoregional control, distant metastasis control, disease-free survival, and overall survival were observed. The median follow-up time was 52.2 months (range: 11-87 months). Epstein-Barr virus infection was positive in 63.2% of patients. Overall disease failure developed in 21 patients, of whom 85.8% belonged to stage III/IV disease. Among these, there were seven locoregional recurrences, three regional recurrences with distant metastases, and eleven distant metastases. The median interval from the date of diagnosis to failure was 26.5 months (range: 16-50 months). Six of ten (60%) locoregional recurrences were treated with reirradiation ± concurrent chemotherapy. The 5-year locoregional control, distant metastasis control, disease-free survival, and overall survival rates of whole cohort were 81.1%, 74.3%, 60.1%, and 73.4%, respectively. Cox regression analyses revealed that neoadjuvant chemotherapy, age, and Epstein-Barr virus were independent predictors for disease-free survival. Neoadjuvant chemotherapy followed by IMRT with or without chemotherapy improves the long-term survival of Saudi patients with nasopharyngeal carcinoma. Distant metastasis was the main pattern of treatment failure. Neoadjuvant chemotherapy, age, and Epstein-Barr virus status before IMRT were important independent prognostic factors.

  18. Patterns of failure and survival in patients with nasopharyngeal carcinoma treated with intensity-modulated radiation therapy in Saudi Arabia

    PubMed Central

    Maklad, Ahmed Marzouk; Bayoumi, Yasser; Senosy Hassan, Mohamed Abdalazez; Elawadi, AbuSaleh A; AlHussain, Hussain; Elyamany, Ashraf; Aldhahri, Saleh F; Al-Qahtani, Khalid Hussain; AlQahtani, Mubarak; Tunio, Mutahir A

    2016-01-01

    Background We aimed to investigate the patterns of failure (locoregional and distant metastasis), associated factors, and treatment outcomes in nasopharyngeal carcinoma patients treated with intensity-modulated radiation therapy (IMRT) combined with chemotherapy. Patients and methods From April 2006 to December 2011, 68 nasopharyngeal carcinoma patients were treated with IMRT and chemotherapy at our hospital. Median radiation doses delivered to gross tumor volume and positive neck nodes were 66–70 Gy, 63 Gy to clinical target volume, and 50.4–56 Gy to clinically negative neck. The clinical toxicities, patterns of failures, locoregional control, distant metastasis control, disease-free survival, and overall survival were observed. Results The median follow-up time was 52.2 months (range: 11–87 months). Epstein–Barr virus infection was positive in 63.2% of patients. Overall disease failure developed in 21 patients, of whom 85.8% belonged to stage III/IV disease. Among these, there were seven locoregional recurrences, three regional recurrences with distant metastases, and eleven distant metastases. The median interval from the date of diagnosis to failure was 26.5 months (range: 16–50 months). Six of ten (60%) locoregional recurrences were treated with reirradiation ± concurrent chemotherapy. The 5-year locoregional control, distant metastasis control, disease-free survival, and overall survival rates of whole cohort were 81.1%, 74.3%, 60.1%, and 73.4%, respectively. Cox regression analyses revealed that neoadjuvant chemotherapy, age, and Epstein–Barr virus were independent predictors for disease-free survival. Conclusion Neoadjuvant chemotherapy followed by IMRT with or without chemotherapy improves the long-term survival of Saudi patients with nasopharyngeal carcinoma. Distant metastasis was the main pattern of treatment failure. Neoadjuvant chemotherapy, age, and Epstein–Barr virus status before IMRT were important independent prognostic factors

  19. Orthostatic heart rate changes in patients with autonomic failure caused by neurodegenerative synucleinopathies.

    PubMed

    Norcliffe-Kaufmann, Lucy; Kaufmann, Horacio; Palma, Jose-Alberto; Shibao, Cyndya A; Biaggioni, Italo; Peltier, Amanda C; Singer, Wolfgang; Low, Phillip A; Goldstein, David S; Gibbons, Christopher H; Freeman, Roy; Robertson, David

    2018-03-01

    Blunted tachycardia during hypotension is a characteristic feature of patients with autonomic failure, but the range has not been defined. This study reports the range of orthostatic heart rate (HR) changes in patients with autonomic failure caused by neurodegenerative synucleinopathies. Patients evaluated at sites of the U.S. Autonomic Consortium (NCT01799915) underwent standardized autonomic function tests and full neurological evaluation. We identified 402 patients with orthostatic hypotension (OH) who had normal sinus rhythm. Of these, 378 had impaired sympathetic activation (ie, neurogenic OH) and based on their neurological examination were diagnosed with Parkinson disease, dementia with Lewy bodies, pure autonomic failure, or multiple system atrophy. The remaining 24 patients had preserved sympathetic activation and their OH was classified as nonneurogenic, due to volume depletion, anemia, or polypharmacy. Patients with neurogenic OH had twice the fall in systolic blood pressure (SBP; -44 ± 25 vs -21 ± 14 mmHg [mean ± standard deviation], p < 0.0001) but only one-third of the increase in HR of those with nonneurogenic OH (8 ± 8 vs 25 ± 11 beats per minute [bpm], p < 0.0001). A ΔHR/ΔSBP ratio of 0.492 bpm/mmHg had excellent sensitivity (91.3%) and specificity (88.4%) to distinguish between patients with neurogenic from nonneurogenic OH (area under the curve = 0.96, p < 0.0001). Within patients with neurogenic OH, HR increased more in those with multiple system atrophy (p = 0.0003), but there was considerable overlap with patients with Lewy body disorders. A blunted HR increase during hypotension suggests a neurogenic cause. A ΔHR/ΔSBP ratio < 0.5 bpm/mmHg is diagnostic of neurogenic OH. Ann Neurol 2018;83:522-531. © 2018 American Neurological Association.

  20. Causes analysis on the failure of government environmental responsibility—Based on the perspective of law and economics

    NASA Astrophysics Data System (ADS)

    Fa, L. N.

    2017-11-01

    As the important Environmental Interests of Subjects, government behooves to undertake the corresponding responsibility of Pollution Control and Environmental Protection. The current situations in our country, however, appear as government environmental responsibility failure. Based on the analysis of law and economics, this article reaches the conclusion through game analysis, principle-agency relationship and utility theory that the prisoners dilemma of environmental interest game between government and enterprise, and the inherent defect of the principal-agency relationship between central government and local government are the inherent causes of government environmental responsibility failure. Many officials tends to graft and corrupt to maximum their own benefit, thus leading to the government failure among environmental pollution treatment and the environmental responsibility to undertake.

  1. The standard deviation of extracellular water/intracellular water is associated with all-cause mortality and technique failure in peritoneal dialysis patients.

    PubMed

    Tian, Jun-Ping; Wang, Hong; Du, Feng-He; Wang, Tao

    2016-09-01

    The mortality rate of peritoneal dialysis (PD) patients is still high, and the predicting factors for PD patient mortality remain to be determined. This study aimed to explore the relationship between the standard deviation (SD) of extracellular water/intracellular water (E/I) and all-cause mortality and technique failure in continuous ambulatory PD (CAPD) patients. All 152 patients came from the PD Center between January 1st 2006 and December 31st 2007. Clinical data and at least five-visit E/I ratio defined by bioelectrical impedance analysis were collected. The patients were followed up till December 31st 2010. The primary outcomes were death from any cause and technique failure. Kaplan-Meier analysis and Cox proportional hazards models were used to identify risk factors for mortality and technique failure in CAPD patients. All patients were followed up for 59.6 ± 23.0 months. The patients were divided into two groups according to their SD of E/I values: lower SD of E/I group (≤0.126) and higher SD of E/I group (>0.126). The patients with higher SD of E/I showed a higher all-cause mortality (log-rank χ (2) = 10.719, P = 0.001) and technique failure (log-rank χ (2) = 9.724, P = 0.002) than those with lower SD of E/I. Cox regression analysis found that SD of E/I independently predicted all-cause mortality (HR  3.551, 95 % CI 1.442-8.746, P = 0.006) and technique failure (HR  2.487, 95 % CI 1.093-5.659, P = 0.030) in CAPD patients after adjustment for confounders except when sensitive C-reactive protein was added into the model. The SD of E/I was a strong independent predictor of all-cause mortality and technique failure in CAPD patients.

  2. Classic Bartter syndrome: a rare cause of failure to thrive in a child.

    PubMed

    Vieira, Helena; Mendes, Leonor; Mendes, Patricia; da Silva, José Esteves

    2012-06-28

    Bartter syndrome is a group of rare autosomal-recessive disorders caused by a defect in distal tubule transport of sodium and chloride. Blood gases and plasma electrolytes raise suspicion of this diagnosis and the definitive diagnosis is made by genetic study. Early treatment improves prognosis. The authors present the case of an 11-month-old child with early failure to thrive and severe regurgitation. Blood gases revealed hypochloraemic metabolic alkalosis, hyponatraemia and hypokalaemia. Blood pressure was normal and polyuria was documented. She began therapy with potassium chloride supplementation and indomethacin. There was clinical improvement and plasma potassium and bicarbonate normalised. The molecular study confirmed it was the classic form of Bartter syndrome. Despite being rare in clinical practice, which may lead to unnecessary medical investigation and diagnosis delay, in a child with failure to thrive, hypochloraemic metabolic alkalosis and hypokalaemia, this diagnosis must be considered.

  3. Classic Bartter syndrome: a rare cause of failure to thrive in a child

    PubMed Central

    Vieira, Helena; Mendes, Leonor; Mendes, Patricia; da Silva, José Esteves

    2012-01-01

    Bartter syndrome is a group of rare autosomal-recessive disorders caused by a defect in distal tubule transport of sodium and chloride. Blood gases and plasma electrolytes raise suspicion of this diagnosis and the definitive diagnosis is made by genetic study. Early treatment improves prognosis. The authors present the case of an 11-month-old child with early failure to thrive and severe regurgitation. Blood gases revealed hypochloraemic metabolic alkalosis, hyponatraemia and hypokalaemia. Blood pressure was normal and polyuria was documented. She began therapy with potassium chloride supplementation and indomethacin. There was clinical improvement and plasma potassium and bicarbonate normalised. The molecular study confirmed it was the classic form of Bartter syndrome. Despite being rare in clinical practice, which may lead to unnecessary medical investigation and diagnosis delay, in a child with failure to thrive, hypochloraemic metabolic alkalosis and hypokalaemia, this diagnosis must be considered. PMID:22744244

  4. Analysis of the cause of failure in nonsurgical endodontic treatment by microscopic inspection during endodontic microsurgery.

    PubMed

    Song, Minju; Kim, Hyeon-Cheol; Lee, Woocheol; Kim, Euiseong

    2011-11-01

    This study examined the clinical causes of failure and the limitation of a previous endodontic treatment by an inspection of the root apex and resected root surface at 26× magnification during endodontic microsurgery. The data were collected from patients in the Department of Conservative Dentistry at the Dental College, Yonsei University in Seoul, Korea between March 2001 and January 2011. All root-filled cases with symptomatic or asymptomatic apical periodontitis were enrolled in this study. All surgical procedures were performed by using an operating microscope. The surface of the apical root to be resected or the resected root surface after methylene blue staining was examined during the surgical procedure and recorded carefully with 26× magnification to determine the state of the previous endodontic treatment by using an operating microscope. Among the 557 cases with periapical surgery, 493 teeth were included in this study. With the exclusion of unknown cases, the most common possible cause of failure was perceived leakage around the canal filling material (30.4%), followed by a missing canal (19.7%), underfilling (14.2%), anatomical complexity (8.7%), overfilling (3.0%), iatrogenic problems (2.8%), apical calculus (1.8%), and cracks (1.2%). The frequency of possible failure causes differed according to the tooth position (P < .001). An appreciation of the root canal anatomy by using an operating microscope in nonsurgical endodontic treatment can make the prognosis more predictable and favorable. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  5. Treatment Failure and Miltefosine Susceptibility in Dermal Leishmaniasis Caused by Leishmania Subgenus Viannia Species

    PubMed Central

    Obonaga, Ricardo; Fernández, Olga Lucía; Valderrama, Liliana; Rubiano, Luisa Consuelo; Castro, Maria del Mar; Barrera, Maria Claudia; Gomez, Maria Adelaida

    2014-01-01

    Treatment failure and parasite drug susceptibility in dermal leishmaniasis caused by Leishmania (Viannia) species are poorly understood. Prospective evaluation of drug susceptibility of strains isolated from individual patients before drug exposure and at clinical failure allows intrinsic and acquired differences in susceptibility to be discerned and analyzed. To determine whether intrinsic susceptibility or loss of susceptibility to miltefosine contributed to treatment failure, we evaluated the miltefosine susceptibility of intracellular amastigotes and promastigotes of six Leishmania (Viannia) braziliensis and six Leishmania (Viannia) panamensis strains isolated sequentially, at diagnosis and treatment failure, from two children and four adults ≥55 years old with concurrent conditions. Four patients presented only cutaneous lesions, one had mucosal disease, and one had disseminated mucocutaneous disease. Expression of the Leishmania drug transporter genes abca2, abca3, abcc2, abcc3, abcg4, abcg6, and LbMT was evaluated by quantitative reverse transcription-PCR (qRT-PCR). Intracellular amastigotes (median 50% effective concentration [EC50], 10.7 μmol/liter) were more susceptible to miltefosine than promastigotes (median EC50, 55.3 μmol/liter) (P < 0.0001). Loss of susceptibility at failure, demonstrated by a miltefosine EC50 of >32 μmol/liter (the upper limit of intracellular amastigote assay), occurred in L. panamensis infection in a child and in L. braziliensis infection in an adult and was accompanied by decreased expression of the miltefosine transporter LbMT (LbMT/β-tubulin, 0.42- to 0.26-fold [P = 0.039] and 0.70- to 0.57-fold [P = 0.009], respectively). LbMT gene polymorphisms were not associated with susceptibility phenotype. Leishmania ABCA3 transporter expression was inversely correlated with miltefosine susceptibility (r = −0.605; P = 0.037). Loss of susceptibility is one of multiple factors involved in failure of miltefosine treatment in dermal

  6. Causes of failure with Szabo technique - an analysis of nine cases.

    PubMed

    Jain, Rajendra Kumar; Padmanabhan, T N C; Chitnis, Nishad

    2013-01-01

    The objective of this case series is to identify and define causes of failure of Szabo technique in rapid-exchange monorail system for ostial lesions. From March 2009 to March 2011, 42 patients with an ostial lesion were treated percutaneously at our institution using Szabo technique in a monorail stent system. All patients received unfractionated heparin during intervention. Loading dose of clopidogrel, followed by clopidogrel and aspirin was administered. In 57% of patients, drug-eluting stents were used and in 42.8% patients bare metal stents. The stent was advanced over both wires, the target wire and the anchor wire. The anchor wire, which was passed through the proximal trailing strut of the stent helps to achieve precise stenting. The procedure was considered to be successful if stent was placed precisely covering the lesion and without stent loss or anchor wire prolapsing. Of the total 42 patients, the procedure was successful in 33, while failed in 9. Majority of failures were due to wire entanglement, which was fixed successfully in 3 cases by removing and reinserting the anchor wire. Out of other three failures, in one stent dislodgment occurred, stent could not cross the lesion in one and in another anchor wire got looped and prolapsed into target vessel. This case series shows that the Szabo technique, in spite of some difficulties like wire entanglement, stent dislodgement and resistance during stent advancement, is a simple and feasible method for treating variety of ostial lesions precisely compared to conventional angioplasty. Copyright © 2013 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

  7. Taxonomy for Common-Cause Failure Vulnerability and Mitigation

    SciTech Connect

    Wood, Richard Thomas; Korsah, Kofi; Mullens, James Allen

    2015-09-01

    Applying current guidance and practices for common-cause failure (CCF) mitigation to digital instrumentation and control (I&C) systems has proven problematic, and the regulatory environment has been unpredictable. The potential for CCF vulnerability inhibits I&C modernization, thereby challenging the long-term sustainability of existing plants. For new plants and advanced reactor concepts, concern about CCF vulnerability in highly integrated digital I&C systems imposes a design burden that results in higher costs and increased complexity. The regulatory uncertainty in determining which mitigation strategies will be acceptable (e.g., what diversity is needed and how much is sufficient) drives designers to adopt complicated, costly solutionsmore » devised for existing plants. To address the conditions that constrain the transition to digital I&C technology by the US nuclear industry, crosscutting research is needed to resolve uncertainty, demonstrate necessary characteristics, and establish an objective basis for qualification of digital technology for nuclear power plant (NPP) I&C applications. To fulfill this research need, Oak Ridge National Laboratory is investigating mitigation of CCF vulnerability for nuclear-qualified applications. The outcome of this research is expected to contribute to a fundamentally sound, comprehensive basis to qualify digital technology for nuclear power applications. This report documents the development of a CCF taxonomy. The basis for the CCF taxonomy was generated by determining consistent terminology and establishing a classification approach. The terminology is based on definitions from standards, guides, and relevant nuclear power industry technical reports. The classification approach is derived from identified classification schemes focused on I&C systems and key characteristics, including failure modes. The CCF taxonomy provides the basis for a systematic organization of key systems aspects relevant to analyzing the

  8. Acute kidney failure

    MedlinePlus

    Kidney failure; Renal failure; Renal failure - acute; ARF; Kidney injury - acute ... There are many possible causes of kidney damage. They include: ... cholesterol (cholesterol emboli) Decreased blood flow due to very ...

  9. Heart Failure

    MedlinePlus

    Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. Heart failure does not mean that your heart has stopped ... and shortness of breath Common causes of heart failure are coronary artery disease, high blood pressure and ...

  10. Development of acute pancreatitis caused by sodium valproate in a patient with bipolar disorder on hemodialysis for chronic renal failure: a case report.

    PubMed

    Okayasu, Hiroaki; Shinozaki, Takahiro; Osone, Akira; Ozeki, Yuji; Shimoda, Kazutaka

    2014-03-29

    Cases of acute pancreatitis caused by sodium valproate (VPA) have been reported by many authors thus far. However, most of these were cases with epilepsy. Chronic renal failure is also regarded as a risk factor for acute pancreatitis. Here, we report a case of acute pancreatitis development due to VPA in a patient with bipolar disorder on hemodialysis for chronic renal failure. The patient was a 52-year-old Japanese male who was diagnosed as bipolar disorder on hemodialysis for renal failure. He was treated with VPA and manic symptoms gradually stabilized. However, the patient complained of severe abdominal pain. Blood amylase was found to be markedly high, and computed tomography revealed pancreatomegaly and an increased amount of peripancreatic fat. Hence, we diagnosed the case as acute pancreatitis caused by VPA. We discontinued oral medication, and he was started on a pancreatic enzyme inhibitor, antibiotics, and transfusion, and he showed improvement. It has been reported that acute pancreatitis induced by VPA is caused by intermediate metabolites of VPA. We consider that patients with renal failure are prone to pancreatitis caused by VPA because of the accumulation of these intermediate metabolites. We need close monitoring for serious adverse effects such as pancreatitis when we prescribe VPA to patients with bipolar disorder on hemodialysis for chronic renal failure, although VPA is safer than other mood stabilizers.

  11. Patterns of Success and Failure in the Transition from School to Work in Australia. Research Report.

    ERIC Educational Resources Information Center

    Lamb, Stephen; McKenzie, Phillip

    Patterns of success and failure in the transition from school to work in Australia in the 1980s-1990s were examined by analyzing data from the Australian Youth Survey. Of those studied, 20% found full-time jobs upon leaving school and remained in full-time employment for the next 7 years, 13% obtained apprenticeships or traineeships leading to…

  12. Clinical patterns and major causes of infertility among Sudanese couples.

    PubMed

    Elussein, Elsir A; Magid, Yagoub M; Omer, Maha M; Adam, Ishag

    2008-10-01

    An understanding of the medical causes of infertility is crucial in order to reduce incidences of Infertility and for improving the clinical management of infertility. Although there were much data on infertility in other African countries, no data exist on infertility in Sudan. Seven hundred and ten Sudanese couples were investigated for the infertility in Khartoum Fertility Center, Sudan: 443 (62.4%) had primary infertility and 267 (37.6%) had secondary infertility. The mean (standard deviation) duration of the infertility was 5.2 (4.3) years. A positive male factor alone was found in 257 (36.2%) couples and a female factor in 350 (49.3%) couples: eleven (1.5%) couples had a combination of male and female factors: and the cause of infertility was unexplained in 92 (13.0%) couples. Oligozoospermia and asthenozoospermia were factors responsible for 16.8% and 17.5% of male infertility, respectively. Failure of ovulation (60.3%) was the most common cause of female infertility. The study revealed a high proportion of secondary infertility and a greater contribution of the female factors to infertility.

  13. [Hydrocephalus in childhood : causes and imaging patterns].

    PubMed

    Pomschar, A; Koerte, I; Peraud, A; Heinen, F; Herber-Jonat, S; Reiser, M; Ertl-Wagner, B

    2012-09-01

    Causes and imaging patterns of hydrocephalus differ depending on the age of the patient. Traditionally, hydrocephalus was classified into non-communicating and communicating hydrocephalus but more recent classifications also take the site of occlusion and the etiology into account. For the diagnostic work-up computed tomography (CT), sonography and magnetic resonance imaging (MRI) are available and MRI is the method of choice for children and adolescents as it allows determination of the cause and location of a possible obstruction. In the first 12-18 months sonography allows evaluation of the lateral ventricles and the third ventricle and CT is usually only chosen in children in emergency situations and/or if no other modality is available. We retrospectively evaluated a population of 785 children and adolescents (426 males aged 0-17 years) referred for MRI between April 2009 and March 2012 due to headaches, somnolence, concentration difficulties or developmental delay. Among these 80 (49 male) met the MRI criteria for hydrocephalus, 75 (46 male) had non-communicating hydrocephalus and 5 (3 male) communicating hydrocephalus. Of the patients 24 (15 male) had posthemorrhagic aqueductal stenosis, 16 (8 male) intracranial tumors, 9 (6 male) Chiari II malformations, 5 (4 male) other congenital malformations including malformations of the Dandy Walker spectrum, 9 (3 male) idiopathic aqueductal stenosis, 7 (5 male) arachnoidal cysts and 10 (8 male) other disorders, such as post-infections, macrocephaly cutis marmorata telangiectatica congenita (M-CMTC) syndrome, mesencephalic arteriovenous malformation (AVM), Langerhans cell histiocystosis. It is important to take the age of the patient and the imaging pattern into account and to exclude tumors when reporting MR images of children with hydrocephalus.

  14. Designed for Workarounds: A Qualitative Study of the Causes of Operational Failures in Hospitals

    PubMed Central

    Tucker, Anita L; Heisler, W Scott; Janisse, Laura D

    2014-01-01

    Frontline care clinicians and staff in hospitals spend at least 10% of their time working around operational failures: situations in which information, supplies, or equipment needed for patient care are insufficient. However, little is known about underlying causes of operational failures and what hospitals can do to reduce their occurrence. To address this gap, we examined the internal supply chains at 2 hospitals with the aim of discovering organizational factors that contribute to operational failures. We conducted in-depth qualitative research, including observations and interviews of more than 80 individuals from 4 nursing units and the ancillary support departments that provide equipment and supplies needed for patient care. We found that a lack of interconnectedness among interdependent departments’ routines was a major source of operational failures. The low levels of interconnectedness occurred because of how the internal supply chains were designed and managed rather than because of employee error or a shortfall in training. Thus, we propose that the time that hospital staff members spend on workarounds can be reduced through deliberate efforts to increase interconnectedness among hospitals’ internal supply departments. Four dimensions of interconnectedness include: 1) hospital-level—rather than department-level—performance measures; 2) internal supply department routines that respond to specific patients’ needs rather than to predetermined stocking routines; 3) knowledge that is necessary for efficient handoffs of materials that is translated across departmental boundaries; and 4) cross-departmental collaboration mechanisms that enable improvement in the flow of materials across departmental boundaries. PMID:25102517

  15. Designed for workarounds: a qualitative study of the causes of operational failures in hospitals.

    PubMed

    Tucker, Anita L; Heisler, W Scott; Janisse, Laura D

    2014-01-01

    Frontline care clinicians and staff in hospitals spend at least 10% of their time working around operational failures: situations in which information, supplies, or equipment needed for patient care are insufficient. However, little is known about underlying causes of operational failures and what hospitals can do to reduce their occurrence. To address this gap, we examined the internal supply chains at 2 hospitals with the aim of discovering organizational factors that contribute to operational failures. We conducted in-depth qualitative research, including observations and interviews of more than 80 individuals from 4 nursing units and the ancillary support departments that provide equipment and supplies needed for patient care. We found that a lack of interconnectedness among interdependent departments' routines was a major source of operational failures. The low levels of interconnectedness occurred because of how the internal supply chains were designed and managed rather than because of employee error or a shortfall in training. Thus, we propose that the time that hospital staff members spend on workarounds can be reduced through deliberate efforts to increase interconnectedness among hospitals' internal supply departments. Four dimensions of interconnectedness include: 1) hospital-level-rather than department-level-performance measures; 2) internal supply department routines that respond to specific patients' needs rather than to predetermined stocking routines; 3) knowledge that is necessary for efficient handoffs of materials that is translated across departmental boundaries; and 4) cross-departmental collaboration mechanisms that enable improvement in the flow of materials across departmental boundaries.

  16. Risk stratification for death and all-cause hospitalization in heart failure clinic outpatients.

    PubMed

    Hummel, Scott L; Ghalib, Hussam H; Ratz, David; Koelling, Todd M

    2013-11-01

    Most heart failure (HF) risk stratification models were developed for inpatient use, and available outpatient models use a complex set of variables. We hypothesized that routinely collected clinical data could predict the 6-month risk of death and all-cause medical hospitalization in HF clinic outpatients. Using a quality improvement database and multivariable Cox modeling, we derived the Heart Failure Patient Severity Index (HFPSI) in the University of Michigan HF clinic (UM cohort, n = 1,536; 314 reached primary outcome). We externally validated the HFPSI in the Ann Arbor Veterans' Affairs HF clinic (VA cohort, n = 445; 106 outcomes) and explored "real-time" HFPSI use (VA-RT cohort, n = 486; 141 outcomes) by tracking VA patients for 6 months from their most recently calculated HFPSI, rather than using an arbitrary start date for the cohort. The HFPSI model included blood urea nitrogen, B-type natriuretic peptide, New York Heart Association class, diabetes status, history of atrial fibrillation/flutter, and all-cause hospitalization within the prior 1 and 2 to 6 months. The concordance c statistics in the UM/VA/VA-RT cohorts were 0.71/0.68/0.74. Kaplan-Meier curves and log-rank testing demonstrated excellent risk stratification, particularly between a large, low-risk group (40% of patients, 6-month event rates in the UM/VA/VA-RT cohorts 8%/12%/12%) and a small, high-risk group (10% of patients, 6-month event rates in the UM/VA/VA-RT cohorts 57%/58%/79%). The HFPSI uses readily available data to predict the 6-month risk of death and/or all-cause medical hospitalization in HF clinic outpatients and could potentially help allocate specialized HF resources within health systems. © 2013.

  17. Causes of failure with Szabo technique – An analysis of nine cases

    PubMed Central

    Jain, Rajendra Kumar; Padmanabhan, T.N.C.; Chitnis, Nishad

    2013-01-01

    Objective The objective of this case series is to identify and define causes of failure of Szabo technique in rapid-exchange monorail system for ostial lesions. Methods and results From March 2009 to March 2011, 42 patients with an ostial lesion were treated percutaneously at our institution using Szabo technique in a monorail stent system. All patients received unfractionated heparin during intervention. Loading dose of clopidogrel, followed by clopidogrel and aspirin was administered. In 57% of patients, drug-eluting stents were used and in 42.8% patients bare metal stents. The stent was advanced over both wires, the target wire and the anchor wire. The anchor wire, which was passed through the proximal trailing strut of the stent helps to achieve precise stenting. The procedure was considered to be successful if stent was placed precisely covering the lesion and without stent loss or anchor wire prolapsing. Of the total 42 patients, the procedure was successful in 33, while failed in 9. Majority of failures were due to wire entanglement, which was fixed successfully in 3 cases by removing and reinserting the anchor wire. Out of other three failures, in one stent dislodgment occurred, stent could not cross the lesion in one and in another anchor wire got looped and prolapsed into target vessel. Conclusion This case series shows that the Szabo technique, in spite of some difficulties like wire entanglement, stent dislodgement and resistance during stent advancement, is a simple and feasible method for treating variety of ostial lesions precisely compared to conventional angioplasty. PMID:23809379

  18. Urea-induced ROS generation causes insulin resistance in mice with chronic renal failure

    PubMed Central

    D’Apolito, Maria; Du, Xueliang; Zong, Haihong; Catucci, Alessandra; Maiuri, Luigi; Trivisano, Tiziana; Pettoello-Mantovani, Massimo; Campanozzi, Angelo; Raia, Valeria; Pessin, Jeffrey E.; Brownlee, Michael; Giardino, Ida

    2009-01-01

    Although supraphysiological concentrations of urea are known to increase oxidative stress in cultured cells, it is generally thought that the elevated levels of urea in chronic renal failure patients have negligible toxicity. We previously demonstrated that ROS increase intracellular protein modification by O-linked β-N-acetylglucosamine (O-GlcNAc), and others showed that increased modification of insulin signaling molecules by O-GlcNAc reduces insulin signal transduction. Because both oxidative stress and insulin resistance have been observed in patients with end-stage renal disease, we sought to determine the role of urea in these phenotypes. Treatment of 3T3-L1 adipocytes with urea at disease-relevant concentrations induced ROS production, caused insulin resistance, increased expression of adipokines retinol binding protein 4 (RBP4) and resistin, and increased O-GlcNAc–modified insulin signaling molecules. Investigation of a mouse model of surgically induced renal failure (uremic mice) revealed increased ROS production, modification of insulin signaling molecules by O-GlcNAc, and increased expression of RBP4 and resistin in visceral adipose tissue. Uremic mice also displayed insulin resistance and glucose intolerance, and treatment with an antioxidant SOD/catalase mimetic normalized these defects. The SOD/catalase mimetic treatment also prevented the development of insulin resistance in normal mice after urea infusion. These data suggest that therapeutic targeting of urea-induced ROS may help reduce the high morbidity and mortality caused by end-stage renal disease. PMID:19955654

  19. De novo Uroplakin IIIa heterozygous mutations cause human renal adysplasia leading to severe kidney failure.

    PubMed

    Jenkins, Dagan; Bitner-Glindzicz, Maria; Malcolm, Sue; Hu, Chih-Chi A; Allison, Jennifer; Winyard, Paul J D; Gullett, Ambrose M; Thomas, David F M; Belk, Rachel A; Feather, Sally A; Sun, Tung-Tien; Woolf, Adrian S

    2005-07-01

    Human renal adysplasia usually occurs sporadically, and bilateral disease is the most common cause of childhood end-stage renal failure, a condition that is lethal without intervention using dialysis or transplantation. De novo heterozygous mutations in Uroplakin IIIa (UPIIIa) are reported in four of 17 children with kidney failure caused by renal adysplasia in the absence of an overt urinary tract obstruction. One girl and one boy in unrelated kindreds had a missense mutation at a CpG dinucleotide in the cytoplasmic domain of UPIIIa (Pro273Leu), both of whom had severe vesicoureteric reflux, and the girl had persistent cloaca; two other patients had de novo mutations in the 3' UTR (963 T-->G; 1003 T-->C), and they had renal adysplasia in the absence of any other anomaly. The mutations were absent in all sets of parents and in siblings, none of whom had radiologic evidence of renal adysplasia, and mutations were absent in two panels of 192 ethnically matched control chromosomes. UPIIIa was expressed in nascent urothelia in ureter and renal pelvis of human embryos, and it is suggested that perturbed urothelial differentiation may generate human kidney malformations, perhaps by altering differentiation of adjacent smooth muscle cells such that the metanephros is exposed to a functional obstruction of urine flow. With advances in renal replacement therapy, children with renal failure, who would otherwise have died, are surviving to adulthood. Therefore, although the mechanisms of action of the UPIIIa mutations have yet to be determined, these findings have important implications regarding genetic counseling of affected individuals who reach reproductive age.

  20. Comparative study of LDR (Manchester system) and HDR image-guided conformal brachytherapy of cervical cancer: patterns of failure, late complications, and survival.

    PubMed

    Narayan, Kailash; van Dyk, Sylvia; Bernshaw, David; Rajasooriyar, Chrishanthi; Kondalsamy-Chennakesavan, Srinivas

    2009-08-01

    To compare patterns of failure, late toxicities, and survival in locally advanced cervical cancer patients treated by either low-dose-rate (LDR) or conformal high-dose-rate (HDRc) brachytherapy as a part of curative radiotherapy. A retrospective comparative study of 217 advanced cervix cancer patients was conducted; 90 of these patients received LDR and 127 received HDRc brachytherapy. All patients were staged using International Federation of Gynecology and Obstetrics (FIGO) rules, had pretreatment magnetic resonance imaging (MRI), and were treated with concurrent cisplatin chemoradiotherapy. Both groups matched for FIGO stage, MRI tumor volume, and uterine invasion status. Local and pelvic failures were similar 12-13% and 14% both in both groups. Abdominal and systemic failures in LDR group were 21% and 24%, whereas corresponding failures in HDRc group were 20% and 24%. Sixty-eight percent (87/127) of patients treated by HDRc remained asymptomatic, whereas 42% (38/90) of patients were asymptomatic from the bowel and bladder symptoms after treatment with LDR. The 5-year OS rate was 60% (SE = 4%). The 5-year failure-free survival rate was 55% (SE = 3%). There was no significant difference between the groups. Image-guided HDRc planning led to a large decrease in late radiation effects in patients treated by HDRc. Patterns of failure and survival were similar in patients treated either by LDR or HDRc.

  1. Causes and treatment of oedema in patients with heart failure.

    PubMed

    Clark, Andrew L; Cleland, John G F

    2013-03-01

    Oedema is one of the fundamental features of heart failure, but the pathophysiology of oedema varies. Patients present along a spectrum ranging from acute pulmonary oedema to gross fluid retention and peripheral oedema (anasarca). In patients with pure pulmonary oedema, the problem is one of acute haemodynamic derangement; the patient does not have excess fluid, but pulmonary venous pressure rises such that the rate of fluid transudation into the interstitium of the lung exceeds the capacity of the pulmonary lymphatics to drain away the fluid. Conversely, in patients with peripheral oedema, the problem is one of fluid retention. Understanding the causes of oedema will enable straightforward, correct management of the condition. For patients with acute pulmonary oedema, vasodilatation is important to reduce cardiac filling pressures. For patients with fluid retention, removing the fluid, using either diuretics or mechanical means, is the most important consideration.

  2. Sarcomere protein gene mutations and inherited heart disease: a beta-cardiac myosin heavy chain mutation causing endocardial fibroelastosis and heart failure.

    PubMed

    Kamisago, Mitsuhiro; Schmitt, Joachim P; McNamara, Dennis; Seidman, Christine; Seidman, J G

    2006-01-01

    Inherited human cardiomyopathies often lead to heart failure. A common feature of these conditions is that affected individuals can express the disease causing mutations for many years without showing clinical signs of the disease. Previous studies have demonstrated that sarcomere protein gene mutations can cause either dilated cardiomyopathy or hypertrophic cardiomyopathy. Here we demonstrate that the Arg442His missense mutation in beta-cardiac myosin heavy chain (betaMHC) causes dilated cardiomyopathy, endocardial fibroelastosis and heart failure at a very early age. Using standard genetic engineering tools we and others have made murine models by introducing human disease causing mutations into mice. The central hypothesis of these studies has been that by identifying the pathophysiological pathways activated by these mutations we can define enzymatic activities that are modified during the disease process and which may be involved in pathways that involve more common forms of cardiac disease. Murine models bearing different mutant myosins are being used to address whether each disease causing mutant betaMHC activates the same or different cellular pathways. Dissecting the molecular pathways modulated by mutations in sarcomere protein genes as well as other genes has already demonstrated that there are multiple pathways leading to cardiac remodelling and heart failure. Defining the mechanisms by which mutations in the same genes activate different cellular pathways remains an important question.

  3. 20 CFR 416.732 - No penalty deduction if you have good cause for failure to report timely.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false No penalty deduction if you have good cause for failure to report timely. 416.732 Section 416.732 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Reports Required Penalty Deductions...

  4. 20 CFR 416.732 - No penalty deduction if you have good cause for failure to report timely.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 2 2013-04-01 2013-04-01 false No penalty deduction if you have good cause for failure to report timely. 416.732 Section 416.732 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Reports Required Penalty Deductions...

  5. SERCA2 Haploinsufficiency in a Mouse Model of Darier Disease Causes a Selective Predisposition to Heart Failure.

    PubMed

    Prasad, Vikram; Lorenz, John N; Lasko, Valerie M; Nieman, Michelle L; Huang, Wei; Wang, Yigang; Wieczorek, David W; Shull, Gary E

    2015-01-01

    Null mutations in one copy of ATP2A2, the gene encoding sarco/endoplasmic reticulum Ca(2+)-ATPase isoform 2 (SERCA2), cause Darier disease in humans, a skin condition involving keratinocytes. Cardiac function appears to be unimpaired in Darier disease patients, with no evidence that SERCA2 haploinsufficiency itself causes heart disease. However, SERCA2 deficiency is widely considered a contributing factor in heart failure. We therefore analyzed Atp2a2 heterozygous mice to determine whether SERCA2 haploinsufficiency can exacerbate specific heart disease conditions. Despite reduced SERCA2a levels in heart, Atp2a2 heterozygous mice resembled humans in exhibiting normal cardiac physiology. When subjected to hypothyroidism or crossed with a transgenic model of reduced myofibrillar Ca(2+)-sensitivity, SERCA2 deficiency caused no enhancement of the disease state. However, when combined with a transgenic model of increased myofibrillar Ca(2+)-sensitivity, SERCA2 haploinsufficiency caused rapid onset of hypertrophy, decompensation, and death. These effects were associated with reduced expression of the antiapoptotic Hax1, increased levels of the proapoptotic genes Chop and Casp12, and evidence of perturbations in energy metabolism. These data reveal myofibrillar Ca(2+)-sensitivity to be an important determinant of the cardiac effects of SERCA2 haploinsufficiency and raise the possibility that Darier disease patients are more susceptible to heart failure under certain conditions.

  6. Failure to activate the in-hospital emergency team: causes and outcomes.

    PubMed

    Barbosa, Vera; Gomes, Ernestina; Vaz, Senio; Azevedo, Gustavo; Fernandes, Gonçalo; Ferreira, Amélia; Araujo, Rui

    2016-01-01

    To determine the incidence of afferent limb failure of the in-hospital Medical Emergency Team, characterizing it and comparing the mortality between the population experiencing afferent limb failure and the population not experiencing afferent limb failure. A total of 478 activations of the Medical Emergency Team of Hospital Pedro Hispano occurred from January 2013 to July 2015. A sample of 285 activations was obtained after excluding incomplete records and activations for patients with less than 6 hours of hospitalization. The sample was divided into two groups: the group experiencing afferent limb failure and the group not experiencing afferent limb failure of the Medical Emergency Team. Both populations were characterized and compared. Statistical significance was set at p ≤ 0.05. Afferent limb failure was observed in 22.1% of activations. The causal analysis revealed significant differences in Medical Emergency Team activation criteria (p = 0.003) in the group experiencing afferent limb failure, with higher rates of Medical Emergency Team activation for cardiac arrest and cardiovascular dysfunction. Regarding patient outcomes, the group experiencing afferent limb failure had higher immediate mortality rates and higher mortality rates at hospital discharge, with no significant differences. No significant differences were found for the other parameters. The incidence of cardiac arrest and the mortality rate were higher in patients experiencing failure of the afferent limb of the Medical Emergency Team. This study highlights the need for health units to invest in the training of all healthcare professionals regarding the Medical Emergency Team activation criteria and emergency medical response system operations.

  7. Cerebral Hemodynamics Patterns by Transcranial Doppler in Patients With Acute Liver Failure.

    PubMed

    Abdo, A; Pérez-Bernal, J; Hinojosa, R; Porras, F; Castellanos, R; Gómez, F; Gutiérrez, J; Castellanos, A; Leal, G; Espinosa, N; Gómez-Bravo, M

    2015-11-01

    About half of patients with acute liver failure (ALF) show clinical signs of cerebral edema and intracranial hypertension. Neuroimaging diagnostics and electroencephalography have poor correlation with intracranial pressure measurement. The objective of this study was to characterize the cerebral hemodynamics patterns with transcranial Doppler (TCD) sonography in patients with ALF. We studied 21 patients diagnosed with ALF, admitted to the intensive care unit (ICU) at the Centro de Investigaciones Médico Quirúrgicas of Cuba. All of these patients had a TCD performed on arrival at ICU, evaluating the following: systolic (SV), diastolic (DV), and medium (MV) flows velocities and pulsatility index (PI) in right middle cerebral artery (RMCA) via temporal windows. The sonographic patterns of cerebral hemodynamics were as follows: low-flow, 12 patients (57.1%); high resistance, 5 patients (23.8%); and hyperemic, 4 patients (19%). Patients who died while waiting had lower MV RMCA (56.1 vs 58.1 cm/s) and higher PI (1.71 vs 1.41) than patients who could undergo transplantation (P = .800 and P = .787, respectively). In patients diagnosed with ALF admitted to the ICU the predominating cerebral hemodynamic pattern was low-flow with resistance increase. The TCD was shown to be a useful tool in the initial evaluation for prognosis and treatment. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Load to Failure and Stiffness

    PubMed Central

    Esquivel, Amanda O.; Duncan, Douglas D.; Dobrasevic, Nikola; Marsh, Stephanie M.; Lemos, Stephen E.

    2015-01-01

    Background: Rotator cuff tendinopathy is a frequent cause of shoulder pain that can lead to decreased strength and range of motion. Failures after using the single-row technique of rotator cuff repair have led to the development of the double-row technique, which is said to allow for more anatomical restoration of the footprint. Purpose: To compare 5 different types of suture patterns while maintaining equality in number of anchors. The hypothesis was that the Mason-Allen–crossed cruciform transosseous-equivalent technique is superior to other suture configurations while maintaining equality in suture limbs and anchors. Study Design: Controlled laboratory study. Methods: A total of 25 fresh-frozen cadaveric shoulders were randomized into 5 suture configuration groups: single-row repair with simple stitch technique; single-row repair with modified Mason-Allen technique; double-row Mason-Allen technique; double-row cross-bridge technique; and double-row suture bridge technique. Load and displacement were recorded at 100 Hz until failure. Stiffness and bone mineral density were also measured. Results: There was no significant difference in peak load at failure, stiffness, maximum displacement at failure, or mean bone mineral density among the 5 suture configuration groups (P < .05). Conclusion: According to study results, when choosing a repair technique, other factors such as number of sutures in the repair should be considered to judge the strength of the repair. Clinical Relevance: Previous in vitro studies have shown the double-row rotator cuff repair to be superior to the single-row repair; however, clinical research does not necessarily support this. This study found no difference when comparing 5 different repair methods, supporting research that suggests the number of sutures and not the pattern can affect biomechanical properties. PMID:26665053

  9. East coast fever caused by Theileria parva is characterized by macrophage activation associated with vasculitis and respiratory failure

    USDA-ARS?s Scientific Manuscript database

    Respiratory failure and death in East Coast Fever (ECF), a clinical syndrome of African cattle caused by the apicomplexan parasite Theileria parva, has historically been attributed to pulmonary infiltration by infected lymphocytes. However, immunohistochemical staining of tissue from T. parva infect...

  10. Dietary patterns and the risk of CVD and all-cause mortality in older British men.

    PubMed

    Atkins, Janice L; Whincup, Peter H; Morris, Richard W; Lennon, Lucy T; Papacosta, Olia; Wannamethee, S Goya

    2016-10-01

    Dietary patterns are a major risk factor for cardiovascular morbidity and mortality; however, few studies have examined this relationship in older adults. We examined prospective associations between dietary patterns and the risk of CVD and all-cause mortality in 3226 older British men, aged 60-79 years and free from CVD at baseline, from the British Regional Heart Study. Baseline FFQ data were used to generate thirty-four food groups. Principal component analysis identified dietary patterns that were categorised into quartiles, with higher quartiles representing higher adherence to the dietary pattern. Cox proportional hazards examined associations between dietary patterns and risk of all-cause mortality and cardiovascular outcomes. We identified three interpretable dietary patterns: 'high fat/low fibre' (high in red meat, meat products, white bread, fried potato, eggs), 'prudent' (high in poultry, fish, fruits, vegetables, legumes, pasta, rice, wholemeal bread, eggs, olive oil) and 'high sugar' (high in biscuits, puddings, chocolates, sweets, sweet spreads, breakfast cereals). During 11 years of follow-up, 899 deaths, 316 CVD-related deaths, 569 CVD events and 301 CHD events occurred. The 'high-fat/low-fibre' dietary pattern was associated with an increased risk of all-cause mortality only, after adjustment for confounders (highest v. lowest quartile; hazard ratio 1·44; 95 % CI 1·13, 1·84). Adherence to a 'high-sugar' diet was associated with a borderline significant trend for an increased risk of CVD and CHD events. The 'prudent' diet did not show a significant trend with cardiovascular outcomes or mortality. Avoiding 'high-fat/low-fibre' and 'high-sugar' dietary components may reduce the risk of cardiovascular events and all-cause mortality in older adults.

  11. Heart Failure

    MedlinePlus

    ... cause heart failure, such as coronary artery disease, high blood pressure, diabetes or obesity. Symptoms Heart failure can be ongoing ( ... include: Not smoking Controlling certain conditions, such as high blood pressure and diabetes Staying physically active Eating healthy foods Maintaining a ...

  12. [Developmental radicular groove as a cause of endodontic failure].

    PubMed

    Fabra Campos, H; Millet Part, J

    1989-01-01

    A clinical case of apical injury on an upper lateral incisor with endodontical and surgical failures in its treatment is presented. Extraction of the incisor and its study at the stereoscopic microscope showed the existence of a developmental groove running from the cingulum to the end of the root, establishing a communication between the crevice and the apical part of the tooth. Bacterial infection through the groove could provide an explanation for treatment failure.

  13. Distinctive Left Ventricular Activations Associated With ECG Pattern in Heart Failure Patients.

    PubMed

    Derval, Nicolas; Duchateau, Josselin; Mahida, Saagar; Eschalier, Romain; Sacher, Frederic; Lumens, Joost; Cochet, Hubert; Denis, Arnaud; Pillois, Xavier; Yamashita, Seigo; Komatsu, Yuki; Ploux, Sylvain; Amraoui, Sana; Zemmoura, Adlane; Ritter, Philippe; Hocini, Mélèze; Haissaguerre, Michel; Jaïs, Pierre; Bordachar, Pierre

    2017-06-01

    In contrast to patients with left bundle branch block (LBBB), heart failure patients with narrow QRS and nonspecific intraventricular conduction delay (NICD) display a relatively limited response to cardiac resynchronization therapy. We sought to compare left ventricular (LV) activation patterns in heart failure patients with narrow QRS and NICD to patients with LBBB using high-density electroanatomic activation maps. Fifty-two heart failure patients (narrow QRS [n=18], LBBB [n=11], NICD [n=23]) underwent 3-dimensional electroanatomic mapping with a high density of mapping points (387±349 LV). Adjunctive scar imaging was available in 37 (71%) patients and was analyzed in relation to activation maps. LBBB patients typically demonstrated (1) a single LV breakthrough at the septum (38±15 ms post-QRS onset); (2) prolonged right-to-left transseptal activation with absence of direct LV Purkinje activity; (3) homogeneous propagation within the LV cavity; and (4) latest activation at the basal lateral LV. In comparison, both NICD and narrow QRS patients demonstrated (1) multiple LV breakthroughs along the posterior or anterior fascicles: narrow QRS versus LBBB, 5±2 versus 1±1; P =0.0004; NICD versus LBBB, 4±2 versus 1±1; P =0.001); (2) evidence of early/pre-QRS LV electrograms with Purkinje potentials; (3) rapid propagation in narrow QRS patients and more heterogeneous propagation in NICD patients; and (4) presence of limited areas of late activation associated with LV scar with high interindividual heterogeneity. In contrast to LBBB patients, narrow QRS and NICD patients are characterized by distinct mechanisms of LV activation, which may predict poor response to cardiac resynchronization therapy. © 2017 American Heart Association, Inc.

  14. Hyperbilirubinemia and rapid fatal hepatic failure in severe combined immunodeficiency caused by adenosine deaminase deficiency (ADA-SCID).

    PubMed

    Kühl, J S; Schwarz, K; Münch, A; Schmugge, M; Pekrun, A; Meisel, C; Wahn, V; Ebell, W; von Bernuth, H

    2011-03-01

    Adenosin deaminase (ADA) deficiency is the cause for Severe Combined Immunodeficiency (SCID) in about 15% of patients with SCID, often presenting as T (-)B (-)NK (-)SCID. Treatment options for ADA-SCID are enzyme replacement, bone marrow transplantation or gene therapy. We here describe the first patient with ADA-SCID and fatal hepatic failure despite bone marrow transplantation from a 10/10 HLA identical related donor. As patients with ADA-SCID may be at yet underestimated increased risk for rapid hepatic failure we speculate whether hepatitis in ADA-SCID should lead to the immediate treatment with enzyme replacement by pegylated ADA. © Georg Thieme Verlag KG Stuttgart · New York.

  15. Chronobiology of death in heart failure.

    PubMed

    Ribas, Nuria; Domingo, Maite; Gastelurrutia, Paloma; Ferrero-Gregori, Andreu; Rull, Pilar; Noguero, Mariana; Garcia, Carmen; Puig, Teresa; Cinca, Juan; Bayes-Genis, Antoni

    2014-05-01

    In the general population, heart events occur more often during early morning, on Mondays, and during winter. However, the chronobiology of death in heart failure has not been analyzed. The aim of this study was to determine the circadian, day of the week, and seasonal variability of all-cause mortality in chronic heart failure. This was an analysis of all consecutive heart failure patients followed in a heart failure unit from January 2003 to December 2008. The circadian moment of death was analyzed at 6-h intervals and was determined by reviewing medical records and by information provided by the relatives. Of 1196 patients (mean [standard deviation] age, 69 [13] years; 62% male), 418 (34.9%) died during a mean (standard deviation) follow-up of 29 (21) months. Survivors were younger, had higher body mass index, left ventricular ejection fraction, glomerular filtration rate, hemoglobin and sodium levels, and lower Framingham risk scores, amino-terminal pro-B type natriuretic peptide, troponin T, and urate values. They were more frequently treated with angiotensin receptor blockers, beta-blockers, mineralocorticoids receptor antagonists, digoxin, nitrates, hydralazine, statins, loop diuretics, and thiazides. The analysis of the circadian and weekly variability did not reveal significant differences between the four 6-h intervals or the days of the week. Mortality occurred more frequently during the winter (30.6%) compared with the other seasons (P = .024). All cause mortality does not follow a circadian pattern, but a seasonal rhythm in patients with heart failure. This finding is in contrast to the circadian rhythmicity of cardiovascular events reported in the general population. Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

  16. Pharmacotherapy Treatment Patterns, Outcomes, and Health Resource Utilization Among Patients with Heart Failure with Reduced Ejection Fraction at a U.S. Academic Medical Center.

    PubMed

    Bress, Adam P; King, Jordan B; Brixner, Diana; Kielhorn, Adrian; Patel, Harshali K; Maya, Juan; Lee, Vinson C; Biskupiak, Joseph; Munger, Mark

    2016-02-01

    To assess clinical characteristics, pharmacotherapy treatment patterns, resource utilization and associated charges, and morbidity and mortality outcomes among a real-world cohort of patients with heart failure with reduced ejection fraction (HFrEF) in an academic medical center setting. Retrospective analysis. Electronic health record database that includes clinical, laboratory, and administrative data for all facilities of the University of Utah Health Care System. A total of 989 adults with prevalent (preexisting) HFrEF, identified by using the International Classification of Diseases, Ninth Revision, Clinical Modification code 428.x (heart failure) between January 1, 2007, and June 30, 2013, and who had a left ventricular ejection fraction of 40% or lower. The cohort had a mean age of 64 ± 15 years and was predominantly white (71%) and male (74%). Patients received β-blockers, angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs), and aldosterone receptor antagonists (ARAs) at rates of 79%, 69%, and 29%, respectively. Patients achieved target doses of β-blockers, ACEIs, and ARBs at rates of only 24%, 31%, and 13%, respectively. Overall, 58% of patients were prescribed dual therapy with a β-blocker and an ACEI or ARB, and 19% were prescribed triple therapy (β-blocker, an ACEI or ARB, and an ARA). Univariate and multivariate logistic regression models were used to assess the association between baseline characteristics with the presence of triple therapy. Two variables were statistically significant in both models: increasing age was associated with a lower odds of triple therapy (univariate: odds ratio [OR] 0.760, 95% confidence interval [CI] 0.673-0.857; multivariate: OR 0.768, 95% CI 0.625-0.942), whereas receipt of an implantable cardiac device was associated with a 2-fold increase in the odds of triple therapy (univariate: OR 2.1, 95% CI 1.4-3.1; multivariate: OR 2.1, 95% CI 1.3-3.5). During a mean ± SD follow

  17. Heart Failure in Women

    PubMed Central

    Bozkurt, Biykem; Khalaf, Shaden

    2017-01-01

    Heart failure is an important cause of morbidity and mortality in women, and they tend to develop it at an older age compared to men. Heart failure with preserved ejection fraction is more common in women than in men and accounts for at least half the cases of heart failure in women. When comparing men and women who have heart failure and a low left ventricular ejection fraction, the women are more symptomatic and have a similarly poor outcome. Overall recommendations for guideline-directed medical therapies show no differences in treatment approaches between men and women. Overall, women are generally underrepresented in clinical trials for heart failure. Further studies are needed to shed light into different mechanisms, causes, and targeted therapies of heart failure in women. PMID:29744014

  18. The importance of scaling for detecting community patterns: success and failure in assemblages of introduced species

    USGS Publications Warehouse

    Allen, Craig R.; Angeler, David G.; Moulton, Michael P.; Holling, Crawford S.

    2015-01-01

    Community saturation can help to explain why biological invasions fail. However, previous research has documented inconsistent relationships between failed invasions (i.e., an invasive species colonizes but goes extinct) and the number of species present in the invaded community. We use data from bird communities of the Hawaiian island of Oahu, which supports a community of 38 successfully established introduced birds and where 37 species were introduced but went extinct (failed invasions). We develop a modified approach to evaluate the effects of community saturation on invasion failure. Our method accounts (1) for the number of species present (NSP) when the species goes extinct rather than during its introduction; and (2) scaling patterns in bird body mass distributions that accounts for the hierarchical organization of ecosystems and the fact that interaction strength amongst species varies with scale. We found that when using NSP at the time of extinction, NSP was higher for failed introductions as compared to successful introductions, supporting the idea that increasing species richness and putative community saturation mediate invasion resistance. Accounting for scale-specific patterns in body size distributions further improved the relationship between NSP and introduction failure. Results show that a better understanding of invasion outcomes can be obtained when scale-specific community structure is accounted for in the analysis.

  19. Virological failure and all-cause mortality in HIV-positive adults with low-level viremia during antiretroviral treatment.

    PubMed

    Elvstam, Olof; Medstrand, Patrik; Yilmaz, Aylin; Isberg, Per-Erik; Gisslén, Magnus; Björkman, Per

    2017-01-01

    Although most HIV-infected individuals achieve undetectable viremia during antiretroviral therapy (ART), a subset have low-level viremia (LLV) of varying duration and magnitude. The impact of LLV on treatment outcomes is unclear. We investigated the association between LLV and virological failure and/or all-cause mortality among Swedish patients receiving ART. HIV-infected patients from two Swedish HIV centers were identified from the nationwide register InfCare HIV. Subjects aged ≥15 years with triple agent ART were included at 12 months after treatment initiation if ≥2 following viral load measurements were available. Patients with 2 consecutive HIV RNA values ≥1000 copies/mL at this time point were excluded. Participants were stratified into four categories depending on viremia profiles: permanently suppressed viremia (<50 copies/mL), LLV 50-199 copies/mL, LLV 200-999 copies/mL and viremia ≥1000 copies/mL. Association between all four viremia categories and all-cause death was calculated using survival analysis with viremia as a time-varying covariate, so that patients could change viremia category during follow-up. Association between the three lower categories and virological failure (≥2 consecutive measurements ≥1000 copies/mL) was calculated in a similar manner. LLV 50-199 copies/mL was recorded in 70/1015 patients (6.9%) and LLV 200-999 copies/mL in 89 (8.8%) during 7812 person-years of follow-up (median 6.5 years). LLV 200-999 copies/mL was associated with virological failure (adjusted hazard ratio 3.14 [95% confidence interval 1.41-7.03, p<0.01]), whereas LLV 50-199 copies/mL was not (1.01 [0.34-4.31, p = 0.99]; median follow-up 4.5 years). LLV 200-999 copies/mL had an adjusted mortality hazard ratio of 2.29 (0.98-5.32, p = 0.05) and LLV 50-199 copies/mL of 2.19 (0.90-5.37, p = 0.09). In this Swedish cohort followed during ART for a median of 4.5 years, LLV 200-999 copies/mL was independently associated with virological failure. Patients with

  20. Assessment of Causes and Patterns of Recurrent Varicose Veins After Surgery

    PubMed Central

    Gad, Mohammed A; Saber, Aly; Hokkam, Emad N

    2012-01-01

    Background: Varicose vein surgery is characterized by high recurrence rate of 60% after 5 years of follow-up observation, and this is a disappointing finding, both for the patient and surgeon. Aim: To identify the possible causes and patterns of recurrent varicose veins. Materials and Methods: 92 patients with recurrent varicose veins were enrolled in this study. Full detailed history, examination, and investigations were done. Results: 30 patients had recurrence after saphenofemoral disconnection, 22 patients with recurrence after saphenofemoral disconnection and stripping below knee, 28 patients recurrence after saphenofemoral disconnection with stripping above knee and 12 patients recurrence after sapheno-popliteal disconnection with stripping. The double great saphenous veins, neovascularization and deep venous thrombosis before and after surgery were the most observed patterns of recurrence. The anatomical patterns of recurrence were more in leg then both leg and thigh pattern. Conclusion: Saphenofemoral ligation with below knee stripping has the least frequency of recurrence, while Trendlenberg operation alone has the highest. PMID:22393548

  1. Global and regional cause-of-death patterns in 1990.

    PubMed Central

    Murray, C. J.; Lopez, A. D.

    1994-01-01

    Demographic estimation techniques suggest that worldwide about 50 million deaths occur each year, of which about 39 million are in the developing countries. In countries with adequate registration of vital statistics, the age at death and the cause can be reliably determined. Only about 30-35% of all deaths are captured by vital registration (excluding sample registration schemes); for the remainder, cause-of-death estimation procedures are required. Indirect methods which model the cause-of-death structure as a function of the level of mortality can provide reasonable estimates for broad cause-of-death groups. Such methods are generally unreliable for more specific causes. In this case, estimates can be constructed from community-level mortality surveillance systems or from epidemiological evidence on specific diseases. Some check on the plausibility of the estimates is possible in view of the hierarchical structure of cause-of-death lists and the well-known age-specific patterns of diseases and injuries. The results of applying these methods to estimate the cause of death for over 120 diseases or injuries, by age, sex and region, are described. The estimates have been derived in order to calculate the years of life lost due to premature death, one of the two components of overall disability-adjusted life years (DALYs) calculated for the 1993 World development report. Previous attempts at cause-of-death estimation have been limited to a few diseases only, with little age-specific detail. The estimates reported in detail here should serve as a useful reference for further public health research to support the determination of health sector priorities. PMID:8062402

  2. Development and validation of a liquid chromatography-mass spectrometry metabonomic platform in human plasma of liver failure caused by hepatitis B virus.

    PubMed

    Zhang, Lijun; Jia, Xiaofang; Peng, Xia; Ou, Qiang; Zhang, Zhengguo; Qiu, Chao; Yao, Yamin; Shen, Fang; Yang, Hua; Ma, Fang; Wang, Jiefei; Yuan, Zhenghong

    2010-10-01

    This paper presents an liquid chromatography (LC)/mass spectrometry (MS)-based metabonomic platform that combined the discovery of differential metabolites through principal component analysis (PCA) with the verification by selective multiple reaction monitoring (MRM). These methods were applied to analyze plasma samples from liver disease patients and healthy donors. LC-MS raw data (about 1000 compounds), from the plasma of liver failure patients (n = 26) and healthy controls (n = 16), were analyzed through the PCA method and a pattern recognition profile that had significant difference between liver failure patients and healthy controls (P < 0.05) was established. The profile was verified in 165 clinical subjects. The specificity and sensitivity of this model in predicting liver failure were 94.3 and 100.0%, respectively. The differential ions with m/z of 414.5, 432.0, 520.5, and 775.0 were verified to be consistent with the results from PCA by MRM mode in 40 clinical samples, and were proved not to be caused by the medicines taken by patients through rat model experiments. The compound with m/z of 520.5 was identified to be 1-Linoleoylglycerophosphocholine or 1-Linoleoylphosphatidylcholine through exact mass measurements performed using Ion Trap-Time-of-Flight MS and METLIN Metabolite Database search. In all, it was the first time to integrate metabonomic study and MRM relative quantification of differential peaks in a large number of clinical samples. Thereafter, a rat model was used to exclude drug effects on the abundance of differential ion peaks. 1-Linoleoylglycerophosphocholine or 1-Linoleoylphosphatidylcholine, a potential biomarker, was identified. The LC/MS-based metabonomic platform could be a powerful tool for the metabonomic screening of plasma biomarkers.

  3. Loss of MeCP2 Causes Urological Dysfunction and Contributes to Death by Kidney Failure in Mouse Models of Rett Syndrome.

    PubMed

    Ward, Christopher S; Huang, Teng-Wei; Herrera, José A; Samaco, Rodney C; Pitcher, Meagan R; Herron, Alan; Skinner, Steven A; Kaufmann, Walter E; Glaze, Daniel G; Percy, Alan K; Neul, Jeffrey L

    2016-01-01

    Rett Syndrome (RTT) is a neurodevelopmental disorder characterized by loss of acquired skills during development, autonomic dysfunction, and an increased risk for premature lethality. Clinical experience identified a subset of individuals with RTT that present with urological dysfunction including individuals with frequent urinary tract infections, kidney stones, and urine retention requiring frequent catheterization for bladder voiding. To determine if urologic dysfunction is a feature of RTT, we queried the Rett Syndrome Natural History Study, a repository of clinical data from over 1000 individuals with RTT and found multiple instances of urological dysfunction. We then evaluated urological function in a mouse model of RTT and found an abnormal pattern of micturition. Both male and female mice possessing Mecp2 mutations show a decrease in urine output per micturition event. Furthermore, we identified signs of kidney failure secondary to urethral obstruction. Although genetic strain background significantly affects both survival and penetrance of the urethral obstruction phenotype, survival and penetrance of urethral obstruction do not directly correlate. We have identified an additional phenotype caused by loss of MeCP2, urological dysfunction. Furthermore, we urge caution in the interpretation of survival data as an endpoint in preclinical studies, especially where causes of mortality are poorly characterized.

  4. Loss of MeCP2 Causes Urological Dysfunction and Contributes to Death by Kidney Failure in Mouse Models of Rett Syndrome

    PubMed Central

    Ward, Christopher S.; Huang, Teng-Wei; Herrera, José A.; Samaco, Rodney C.; Pitcher, Meagan R.; Herron, Alan; Skinner, Steven A.; Kaufmann, Walter E.; Glaze, Daniel G.; Percy, Alan K.; Neul, Jeffrey L.

    2016-01-01

    Rett Syndrome (RTT) is a neurodevelopmental disorder characterized by loss of acquired skills during development, autonomic dysfunction, and an increased risk for premature lethality. Clinical experience identified a subset of individuals with RTT that present with urological dysfunction including individuals with frequent urinary tract infections, kidney stones, and urine retention requiring frequent catheterization for bladder voiding. To determine if urologic dysfunction is a feature of RTT, we queried the Rett Syndrome Natural History Study, a repository of clinical data from over 1000 individuals with RTT and found multiple instances of urological dysfunction. We then evaluated urological function in a mouse model of RTT and found an abnormal pattern of micturition. Both male and female mice possessing Mecp2 mutations show a decrease in urine output per micturition event. Furthermore, we identified signs of kidney failure secondary to urethral obstruction. Although genetic strain background significantly affects both survival and penetrance of the urethral obstruction phenotype, survival and penetrance of urethral obstruction do not directly correlate. We have identified an additional phenotype caused by loss of MeCP2, urological dysfunction. Furthermore, we urge caution in the interpretation of survival data as an endpoint in preclinical studies, especially where causes of mortality are poorly characterized. PMID:27828991

  5. Quasi-static and dynamic experimental studies on the tensile strength and failure pattern of concrete and mortar discs.

    PubMed

    Jin, Xiaochao; Hou, Cheng; Fan, Xueling; Lu, Chunsheng; Yang, Huawei; Shu, Xuefeng; Wang, Zhihua

    2017-11-10

    As concrete and mortar materials widely used in structural engineering may suffer dynamic loadings, studies on their mechanical properties under different strain rates are of great importance. In this paper, based on splitting tests of Brazilian discs, the tensile strength and failure pattern of concrete and mortar were investigated under quasi-static and dynamic loadings with a strain rate of 1-200 s -1 . It is shown that the quasi-static tensile strength of mortar is higher than that of concrete since coarse aggregates weaken the interface bonding strength of the latter. Numerical results confirmed that the plane stress hypothesis lead to a lower value tensile strength for the cylindrical specimens. With the increase of strain rates, dynamic tensile strengths of concrete and mortar significantly increase, and their failure patterns change form a single crack to multiple cracks and even fragment. Furthermore, a relationship between the dynamic increase factor and strain rate was established by using a linear fitting algorithm, which can be conveniently used to calculate the dynamic increase factor of concrete-like materials in engineering applications.

  6. An informatics-based approach to reducing heart failure all-cause readmissions: the Stanford heart failure dashboard.

    PubMed

    Banerjee, Dipanjan; Thompson, Christine; Kell, Charlene; Shetty, Rajesh; Vetteth, Yohan; Grossman, Helene; DiBiase, Aria; Fowler, Michael

    2017-05-01

    Reduction of 30-day all-cause readmissions for heart failure (HF) has become an important quality-of-care metric for health care systems. Many hospitals have implemented quality improvement programs designed to reduce 30-day all-cause readmissions for HF. Electronic medical record (EMR)-based measures have been employed to aid in these efforts, but their use has been largely adjunctive to, rather than integrated with, the overall effort. We hypothesized that a comprehensive EMR-based approach utilizing an HF dashboard in addition to an established HF readmission reduction program would further reduce 30-day all-cause index hospital readmission rates for HF. After establishing a quality improvement program to reduce 30-day HF readmission rates, we instituted EMR-based measures designed to improve cohort identification, intervention tracking, and readmission analysis, the latter 2 supported by an electronic HF dashboard. Our primary outcome measure was the 30-day index hospital readmission rate for HF, with secondary measures including the accuracy of identification of patients with HF and the percentage of patients receiving interventions designed to reduce all-cause readmissions for HF. The HF dashboard facilitated improved penetration of our interventions and reduced readmission rates by allowing the clinical team to easily identify cohorts with high readmission rates and/or low intervention rates. We significantly reduced 30-day index hospital all-cause HF readmission rates from 18.2% at baseline to 14% after implementation of our quality improvement program ( P  = .045). Implementation of our EMR-based approach further significantly reduced 30-day index hospital readmission rates for HF to 10.1% ( P for trend = .0001). Daily time to screen patients decreased from 1 hour to 15 minutes, accuracy of cohort identification improved from 83% to 94.6% ( P  = .0001), and the percentage of patients receiving our interventions, such as patient education

  7. Sleep in heart failure.

    PubMed

    Naughton, Matthew T; Lorenzi-Filho, Geraldo

    2009-01-01

    Sleep plays a large role in patients with heart failure. In normal subjects, sleep is usually in a supine position with reduced sympathetic drive, elevated vagal tone and as such a relatively lower cardiac output and minute ventilation, allowing for recuperation. Patients with heart failure may not experience the same degree of autonomic activity change and the supine position may place a large strain on the pulmonary system. More than half of all heart failure patients have one of two types of sleep apnea: either obstructive or central sleep apnea. Some patients have both types. Obstructive sleep apnea is likely to be a cause of heart failure due to large negative intrathoracic pressures, apnea related hypoxemia and hypercapnia, terminated by an arousal and surge in systemic blood pressure associated with endothelial damage and resultant premature atherosclerosis. Reversal of obstructive sleep apnea improves blood pressure, systolic contraction and autonomic dysfunction however mortality studies are lacking. Central sleep apnea with Cheyne Stokes pattern of respiration (CSA-CSR) occurs as a result of increased central controller (brainstem driving ventilation) and plant (ventilation driving CO2) gain in the setting of a delayed feed back (i.e., low cardiac output). It is thought this type of apnea is a result of moderately to severely impaired cardiac function and is possibly indicative of high mortality. Treatment of CSA-CSR is best undertaken by treating the underlying cardiac condition which may include with medications, pacemakers, transplantation or continuous positive airway pressure (CPAP). In such patients CPAP exerts unique effects to assist cardiac function and reduce pulmonary edema. Whether CPAP improves survival in this heart failure population remains to be determined.

  8. Squamous Cell Carcinoma of the Anal Canal: Patterns and Predictors of Failure and Implications for Intensity-Modulated Radiation Treatment Planning

    SciTech Connect

    Wright, Jean L., E-mail: jwright3@med.miami.ed; Patil, Sujata M.; Temple, Larissa K.F.

    2010-11-15

    Purpose: Intensity-modulated radiation treatment (IMRT) is increasingly used in the treatment of squamous cell carcinoma of the anal canal (SCCAC). Prevention of locoregional failure (LRF) using IMRT requires appropriate clinical target volume (CTV) definition. To better define the CTV for IMRT, we evaluated patterns and predictors of LRF in SCCAC patients given conventional radiation treatment. Methods and Materials: We reviewed records of 180 SCCAC patients treated with conventional radiation with or without chemotherapy at our institution between January 1990 and March 2007. All patients received radiation; the median primary tumor dose was 45 Gy. A total of 173 patients alsomore » received mitomycin-based chemotherapy. Results: Median follow-up was 40 months. Actuarial 3-year colostomy-free survival was 89% and overall survival (OS) 88%. Actuarial 3-year LRF was 23%. A total of 45 patients had LRF, with 35 (78%) occurring locally in the primary site (25 local only, 10 local and regional); however, 20 (44%) had regional components of failure within the pelvis or inguinal nodes (10 regional only, 10 local and regional). Cumulative sites of LRF (patients may have one or more site of failure) were as follows: primary, 35; inguinal, 8; external perianal, 5; common iliac, 4; presacral, 3; distal rectum, 2; external iliac, 2; and internal iliac, 2. All patients with common iliac failure had cT3 or N+ disease. Conclusions: The observed patterns of failure support inclusion of the inguinal and all pelvic nodal groups in the CTV for IMRT. In patients with advanced tumor or nodal stage, common iliac nodes should also be included in the CTV.« less

  9. Program Helps In Analysis Of Failures

    NASA Technical Reports Server (NTRS)

    Stevenson, R. W.; Austin, M. E.; Miller, J. G.

    1993-01-01

    Failure Environment Analysis Tool (FEAT) computer program developed to enable people to see and better understand effects of failures in system. User selects failures from either engineering schematic diagrams or digraph-model graphics, and effects or potential causes of failures highlighted in color on same schematic-diagram or digraph representation. Uses digraph models to answer two questions: What will happen to system if set of failure events occurs? and What are possible causes of set of selected failures? Helps design reviewers understand exactly what redundancies built into system and where there is need to protect weak parts of system or remove them by redesign. Program also useful in operations, where it helps identify causes of failure after they occur. FEAT reduces costs of evaluation of designs, training, and learning how failures propagate through system. Written using Macintosh Programmers Workshop C v3.1. Can be linked with CLIPS 5.0 (MSC-21927, available from COSMIC).

  10. The Hot (Invisible?) Hand: Can Time Sequence Patterns of Success/Failure in Sports Be Modeled as Repeated Random Independent Trials?

    PubMed Central

    Yaari, Gur; Eisenmann, Shmuel

    2011-01-01

    The long lasting debate initiated by Gilovich, Vallone and Tversky in is revisited: does a “hot hand” phenomenon exist in sports? Hereby we come back to one of the cases analyzed by the original study, but with a much larger data set: all free throws taken during five regular seasons () of the National Basketball Association (NBA). Evidence supporting the existence of the “hot hand” phenomenon is provided. However, while statistical traces of this phenomenon are observed in the data, an open question still remains: are these non random patterns a result of “success breeds success” and “failure breeds failure” mechanisms or simply “better” and “worse” periods? Although free throws data is not adequate to answer this question in a definite way, we speculate based on it, that the latter is the dominant cause behind the appearance of the “hot hand” phenomenon in the data. PMID:21998630

  11. Patterns of Failure in Pediatric Rhabdomyosarcoma After Proton Therapy

    SciTech Connect

    Vern-Gross, Tamara Z.; Indelicato, Daniel J., E-mail: dindelicato@floridaproton.org; Bradley, Julie A.

    Purpose: To report on the patterns of failure in children with rhabdomyosarcoma treated with proton therapy. Patients and Methods: Between February 2007 and November 2013, 66 children with a median age of 4.1 years (range, 0.6-15.3 years) diagnosed with nonmetastatic rhabdomyosarcoma were treated with proton therapy. Clinical target volume 1 was defined as the prechemotherapy tumor plus a 1-cm anatomically constrained margin. Clinical target volume 2 was defined as the postchemotherapy tumor (or tumor bed) plus a 0.5-cm anatomically constrained margin, further expanded to encompass potential pathways of spread, including soft tissue infiltrated with tumor at diagnosis. Results: Of the 66 children,more » 11 developed locally progressive disease at a median of 16 months (range, 14-32 months), for an actuarial 2-year local control rate of 88%. Among the children who progressed, median age and tumor size at diagnosis were 6.7 years (range, 0.6-16 years) and 6 cm (range, 2-8 cm), respectively. Of the recurrences, 64% and 36% were embryonal and alveolar, respectively. Disease progression was observed in 7 (64%) parameningeal, 2 (18%) head and neck (other), and 2 (18%) bladder/prostate subsites. At diagnosis, 8 of 11 patients who developed a recurrence were Intergroup Rhabdomyosarcoma Study stage 3, and all 11 were group III. Of the relapses, 100% (11 of 11) were confirmed as in-field within the composite 95% isodose line. One of the 11 patients (9%) developed a new simultaneous regional nodal recurrence outside of the previously treated radiation field. Conclusion: Early data suggest that the sharp dosimetric gradient associated with proton therapy is not associated with an increased risk of marginal failure. Routine use of a 0.5- to 1-cm clinical target volume 1/2 margin with highly conformal proton therapy does not compromise local control in children diagnosed with rhabdomyosarcoma with unfavorable risk features.« less

  12. Nonacetaminophen Drug-Induced Acute Liver Failure.

    PubMed

    Thomas, Arul M; Lewis, James H

    2018-05-01

    Acute liver failure of all causes is diagnosed in between 2000 and 2500 patients annually in the United States. Drug-induced acute liver failure is the leading cause of acute liver failure, accounting for more than 50% of cases. Nonacetaminophen drug injury represents 11% of all cases in the latest registry from the US Acute Liver Failure Study Group. Although rare, acute liver failure is clinically dramatic when it occurs, and requires a multidisciplinary approach to management. In contrast with acetaminophen-induced acute liver failure, non-acetaminophen-induced acute liver failure has a more ominous prognosis with a lower liver transplant-free survival. Copyright © 2018 Elsevier Inc. All rights reserved.

  13. Graphical Displays Assist In Analysis Of Failures

    NASA Technical Reports Server (NTRS)

    Pack, Ginger; Wadsworth, David; Razavipour, Reza

    1995-01-01

    Failure Environment Analysis Tool (FEAT) computer program enables people to see and better understand effects of failures in system. Uses digraph models to determine what will happen to system if set of failure events occurs and to identify possible causes of selected set of failures. Digraphs or engineering schematics used. Also used in operations to help identify causes of failures after they occur. Written in C language.

  14. Failure analysis of aluminum alloy components

    NASA Technical Reports Server (NTRS)

    Johari, O.; Corvin, I.; Staschke, J.

    1973-01-01

    Analysis of six service failures in aluminum alloy components which failed in aerospace applications is reported. Identification of fracture surface features from fatigue and overload modes was straightforward, though the specimens were not always in a clean, smear-free condition most suitable for failure analysis. The presence of corrosion products and of chemically attacked or mechanically rubbed areas here hindered precise determination of the cause of crack initiation, which was then indirectly inferred from the scanning electron fractography results. In five failures the crack propagation was by fatigue, though in each case the fatigue crack initiated from a different cause. Some of these causes could be eliminated in future components by better process control. In one failure, the cause was determined to be impact during a crash; the features of impact fracture were distinguished from overload fractures by direct comparisons of the received specimens with laboratory-generated failures.

  15. Heart failure in South America.

    PubMed

    Bocchi, Edimar Alcides

    2013-05-01

    Continued assessment of temporal trends in mortality and epidemiology of specific heart failure in South America is needed to provide a scientific basis for rational allocation of the limited health care resources, and strategies to reduce risk and predict the future burden of heart failure. The epidemiology of heart failure in South America was reviewed. Heart failure is the main cause of hospitalization based on available data from approximately 50% of the South American population. The main etiologies of heart failure are ischemic, idiopathic dilated cardiomyopathy, valvular, hypertensive and chagasic etiologies. In endemic areas, Chagas heart disease may be responsible by 41% of the HF cases. Also, heart failure presents high mortality especially in patients with Chagas etiology. Heart failure and etiologies associated with heart failure may be responsible for 6.3% of causes of deaths. Rheumatic fever is the leading cause of valvular heart disease. However, a tendency to reduction of HF mortality due to Chagas heart disease from 1985 to 2006, and reduction in mortality due to HF from 1999 to 2005 were observed in selected states in Brazil. The findings have important public health implications because the allocation of health care resources, and strategies to reduce risk of heart failure should also consider the control of neglected Chagas disease and rheumatic fever in South American countries.

  16. Heart Failure in South America

    PubMed Central

    Bocchi, Edimar Alcides

    2013-01-01

    Continued assessment of temporal trends in mortality and epidemiology of specific heart failure in South America is needed to provide a scientific basis for rational allocation of the limited health care resources, and strategies to reduce risk and predict the future burden of heart failure. The epidemiology of heart failure in South America was reviewed. Heart failure is the main cause of hospitalization based on available data from approximately 50% of the South American population. The main etiologies of heart failure are ischemic, idiopathic dilated cardiomyopathy, valvular, hypertensive and chagasic etiologies. In endemic areas, Chagas heart disease may be responsible by 41% of the HF cases. Also, heart failure presents high mortality especially in patients with Chagas etiology. Heart failure and etiologies associated with heart failure may be responsible for 6.3% of causes of deaths. Rheumatic fever is the leading cause of valvular heart disease. However, a tendency to reduction of HF mortality due to Chagas heart disease from 1985 to 2006, and reduction in mortality due to HF from 1999 to 2005 were observed in selected states in Brazil. The findings have important public health implications because the allocation of health care resources, and strategies to reduce risk of heart failure should also consider the control of neglected Chagas disease and rheumatic fever in South American countries. PMID:23597301

  17. Three-dimensional conformal radiotherapy with concurrent chemotherapy for postoperative recurrence of esophageal squamous cell carcinoma: clinical efficacy and failure pattern

    PubMed Central

    2013-01-01

    Background To assess the therapeutic outcome and failure pattern of three-dimensional conformal radiotherapy (3D-CRT)-based concurrent chemoradiotherapy (CCRT) for recurrence of esophageal squamous cell carcinoma (SCC) after radical surgery. Methods Treatment outcome and failure pattern were retrospectively evaluated in 83 patients with localized cervical and thoracic recurrences after radical surgery for thoracic esophageal SCC. All patients were treated with 3DCRT-based CCRT (median radiation dose 60 Gy), in which 39 received concurrent cisplatin plus 5-fluorouracil (PF), and 44 received concurrent docetaxel plus cisplatin (TP). Treatment response was evaluated at 1–3 months after CCRT. Results With a median follow-up of 34 months (range, 2–116 months), the 3-year overall survival (OS) of all the patients was 51.8% and the median OS time was 43.0 months. The overall tumor response rate was 75.9% (63/83), with a complete remission (CR) rate of 44.6% (37/83). In univariate analysis, tumor response after CCRT (p = 0.000), recurrence site (p = 0.028) and concurrent chemotherapy (p = 0.090) showed a trend favoring better OS. Multivariate analysis revealed that tumor response after CCRT (p = 0.000) and concurrent chemotherapy (p = 0.010) were independent predictors of OS. Forty-seven patients had progressive diseases after CCRT, 27 had local failure (27/47, 57.4%), 18 had distant metastasis (18/47, 38.3%) and 2 had both local and distant failures (2/47, 4.3%). Conclusions 3DCRT-based CCRT is effective in postoperatively recurrent esophageal SCC. Patients that obtained complete remission after CCRT appeared to achieve long-term OS and might benefit from concurrent TP regimen. Local and distant failures remained high and prospective studies are needed to validate these factors. PMID:24139225

  18. Three-dimensional conformal radiotherapy with concurrent chemotherapy for postoperative recurrence of esophageal squamous cell carcinoma: clinical efficacy and failure pattern.

    PubMed

    Bao, Yong; Liu, ShiLiang; Zhou, QiChao; Cai, PeiQiang; Anfossi, Simone; Li, QiaoQiao; Hu, YongHong; Liu, MengZhong; Fu, JianHua; Rong, TieHua; Li, Qun; Liu, Hui

    2013-10-18

    To assess the therapeutic outcome and failure pattern of three-dimensional conformal radiotherapy (3D-CRT)-based concurrent chemoradiotherapy (CCRT) for recurrence of esophageal squamous cell carcinoma (SCC) after radical surgery. Treatment outcome and failure pattern were retrospectively evaluated in 83 patients with localized cervical and thoracic recurrences after radical surgery for thoracic esophageal SCC. All patients were treated with 3DCRT-based CCRT (median radiation dose 60 Gy), in which 39 received concurrent cisplatin plus 5-fluorouracil (PF), and 44 received concurrent docetaxel plus cisplatin (TP). Treatment response was evaluated at 1-3 months after CCRT. With a median follow-up of 34 months (range, 2-116 months), the 3-year overall survival (OS) of all the patients was 51.8% and the median OS time was 43.0 months. The overall tumor response rate was 75.9% (63/83), with a complete remission (CR) rate of 44.6% (37/83). In univariate analysis, tumor response after CCRT (p = 0.000), recurrence site (p = 0.028) and concurrent chemotherapy (p = 0.090) showed a trend favoring better OS. Multivariate analysis revealed that tumor response after CCRT (p = 0.000) and concurrent chemotherapy (p = 0.010) were independent predictors of OS. Forty-seven patients had progressive diseases after CCRT, 27 had local failure (27/47, 57.4%), 18 had distant metastasis (18/47, 38.3%) and 2 had both local and distant failures (2/47, 4.3%). 3DCRT-based CCRT is effective in postoperatively recurrent esophageal SCC. Patients that obtained complete remission after CCRT appeared to achieve long-term OS and might benefit from concurrent TP regimen. Local and distant failures remained high and prospective studies are needed to validate these factors.

  19. Mitochondria and heart failure.

    PubMed

    Murray, Andrew J; Edwards, Lindsay M; Clarke, Kieran

    2007-11-01

    Energetic abnormalities in cardiac and skeletal muscle occur in heart failure and correlate with clinical symptoms and mortality. It is likely that the cellular mechanism leading to energetic failure involves mitochondrial dysfunction. Therefore, it is crucial to elucidate the causes of mitochondrial myopathy, in order to improve cardiac and skeletal muscle function, and hence quality of life, in heart failure patients. Recent studies identified several potential stresses that lead to mitochondrial dysfunction in heart failure. Chronically elevated plasma free fatty acid levels in heart failure are associated with decreased metabolic efficiency and cellular insulin resistance. Tissue hypoxia, resulting from low cardiac output and endothelial impairment, can lead to oxidative stress and mitochondrial DNA damage, which in turn causes dysfunction and loss of mitochondrial mass. Therapies aimed at protecting mitochondrial function have shown promise in patients and animal models with heart failure. Despite current therapies, which provide substantial benefit to patients, heart failure remains a relentlessly progressive disease, and new approaches to treatment are necessary. Novel pharmacological agents are needed that optimize substrate metabolism and maintain mitochondrial integrity, improve oxidative capacity in heart and skeletal muscle, and alleviate many of the clinical symptoms associated with heart failure.

  20. Virological failure and all-cause mortality in HIV-positive adults with low-level viremia during antiretroviral treatment

    PubMed Central

    Medstrand, Patrik; Yilmaz, Aylin; Isberg, Per-Erik; Gisslén, Magnus; Björkman, Per

    2017-01-01

    Objective Although most HIV-infected individuals achieve undetectable viremia during antiretroviral therapy (ART), a subset have low-level viremia (LLV) of varying duration and magnitude. The impact of LLV on treatment outcomes is unclear. We investigated the association between LLV and virological failure and/or all-cause mortality among Swedish patients receiving ART. Methods HIV-infected patients from two Swedish HIV centers were identified from the nationwide register InfCare HIV. Subjects aged ≥15 years with triple agent ART were included at 12 months after treatment initiation if ≥2 following viral load measurements were available. Patients with 2 consecutive HIV RNA values ≥1000 copies/mL at this time point were excluded. Participants were stratified into four categories depending on viremia profiles: permanently suppressed viremia (<50 copies/mL), LLV 50–199 copies/mL, LLV 200–999 copies/mL and viremia ≥1000 copies/mL. Association between all four viremia categories and all-cause death was calculated using survival analysis with viremia as a time-varying covariate, so that patients could change viremia category during follow-up. Association between the three lower categories and virological failure (≥2 consecutive measurements ≥1000 copies/mL) was calculated in a similar manner. Results LLV 50–199 copies/mL was recorded in 70/1015 patients (6.9%) and LLV 200–999 copies/mL in 89 (8.8%) during 7812 person-years of follow-up (median 6.5 years). LLV 200–999 copies/mL was associated with virological failure (adjusted hazard ratio 3.14 [95% confidence interval 1.41–7.03, p<0.01]), whereas LLV 50–199 copies/mL was not (1.01 [0.34–4.31, p = 0.99]; median follow-up 4.5 years). LLV 200–999 copies/mL had an adjusted mortality hazard ratio of 2.29 (0.98–5.32, p = 0.05) and LLV 50–199 copies/mL of 2.19 (0.90–5.37, p = 0.09). Conclusions In this Swedish cohort followed during ART for a median of 4.5 years, LLV 200–999 copies/mL was

  1. Potential role of gas hydrate decomposition in generating submarine slope failures: Chapter 12

    USGS Publications Warehouse

    Pauli, Charles K.; Ussler, William III; Dillon, William P.; Max, Michael D.

    2003-01-01

    Gas hydrate decomposition is hypothesized to be a factor in generating weakness in continental margin sediments that may help explain some of the observed patterns of continental margin sediment instability. The processes associated with formation and decomposition of gas hydrate can cause the strengthening of sediments in which gas hydrate grow and the weakening of sediments in which gas hydrate decomposes. The weakened sediments may form horizons along which the potential for sediment failure is increased. While a causal relationship between slope failures and gas hydrate decomposition has not been proven, a number of empirical observations support their potential connection.

  2. Paleolithic and Mediterranean Diet Pattern Scores Are Inversely Associated with All-Cause and Cause-Specific Mortality in Adults.

    PubMed

    Whalen, Kristine A; Judd, Suzanne; McCullough, Marjorie L; Flanders, W Dana; Hartman, Terryl J; Bostick, Roberd M

    2017-04-01

    Background: Poor diet quality is associated with a higher risk of many chronic diseases that are among the leading causes of death in the United States. It has been hypothesized that evolutionary discordance may account for some of the higher incidence and mortality from these diseases. Objective: We investigated associations of 2 diet pattern scores, the Paleolithic and the Mediterranean, with all-cause and cause-specific mortality in the REGARDS (REasons for Geographic and Racial Differences in Stroke) study, a longitudinal cohort of black and white men and women ≥45 y of age. Methods: Participants completed questionnaires, including a Block food-frequency questionnaire (FFQ), at baseline and were contacted every 6 mo to determine their health status. Of the analytic cohort ( n = 21,423), a total of 2513 participants died during a median follow-up of 6.25 y. We created diet scores from FFQ responses and assessed their associations with mortality using multivariable Cox proportional hazards regression models adjusting for major risk factors. Results: For those in the highest relative to the lowest quintiles of the Paleolithic and Mediterranean diet scores, the multivariable adjusted HRs for all-cause mortality were, respectively, 0.77 (95% CI: 0.67, 0.89; P- trend < 0.01) and 0.63 (95% CI: 0.54, 0.73; P- trend < 0.01). The corresponding HRs for all-cancer mortality were 0.72 (95% CI: 0.55, 0.95; P- trend = 0.03) and 0.64 (95% CI: 0.48, 0.84; P- trend = 0.01), and for all-cardiovascular disease mortality they were 0.78 (95% CI: 0.61, 1.00; P- trend = 0.06) and HR: 0.68 (95% CI: 0.53, 0.88; P- trend = 0.01). Conclusions: Findings from this biracial prospective study suggest that diets closer to Paleolithic or Mediterranean diet patterns may be inversely associated with all-cause and cause-specific mortality. © 2017 American Society for Nutrition.

  3. Skin Cancer of the Head and Neck With Perineural Invasion: Defining the Clinical Target Volumes Based on the Pattern of Failure

    SciTech Connect

    Gluck, Iris; Ibrahim, Mohannad; Popovtzer, Aron

    2009-05-01

    Purpose: To analyze patterns of failure in patients with head-and-neck cutaneous squamous cell carcinoma (HNCSCC) and clinical/radiologic evidence of perineural invasion (CPNI), in order to define neural clinical target volume (CTV) for treatment planning. Methods and Materials: Patients treated with three-dimensional (3D) conformal or intensity-modulated radiotherapy (IMRT) for HNCSCC with CPNI were included in the study. A retrospective review of the clinical charts, radiotherapy (RT) plans and radiologic studies has been conducted. Results: Eleven consecutive patients with HNCSCCs with CPNI were treated from 2000 through 2007. Most patients underwent multiple surgical procedures and RT courses. The most prevalent failure patternmore » was along cranial nerves (CNs), and multiple CNs were ultimately involved in the majority of cases. In all cases the involved CNs at recurrence were the main nerves innervating the primary tumor sites, as well as their major communicating nerves. We have found several distinct patterns of disease spread along specific CNs depending on the skin regions harboring the primary tumors, including multiple branches of CN V and VII. These patterns and the pertinent anatomy are detailed in the this article. Conclusions: Predictable disease spread patterns along cranial nerves supplying the primary tumor sites were found in this study. Awareness of these patterns, as well as knowledge of the relevant cranial nerve anatomy, should be the basis for CTV definition and delineation for RT treatment planning.« less

  4. The cell wall components peptidoglycan and lipoteichoic acid from Staphylococcus aureus act in synergy to cause shock and multiple organ failure.

    PubMed Central

    De Kimpe, S J; Kengatharan, M; Thiemermann, C; Vane, J R

    1995-01-01

    Although the incidence of Gram-positive sepsis has risen strongly, it is unclear how Gram-positive organisms (without endotoxin) initiate septic shock. We investigated whether two cell wall components from Staphylococcus aureus, peptidoglycan (PepG) and lipoteichoic acid (LTA), can induce the inflammatory response and multiple organ dysfunction syndrome (MODS) associated with septic shock caused by Gram-positive organisms. In cultured macrophages, LTA (10 micrograms/ml), but not PepG (100 micrograms/ml), induces the release of nitric oxide measured as nitrite. PepG, however, caused a 4-fold increase in the production of nitrite elicited by LTA. Furthermore, PepG antibodies inhibited the release of nitrite elicited by killed S. aureus. Administration of both PepG (10 mg/kg; i.v.) and LTA (3 mg/kg; i.v.) in anesthetized rats resulted in the release of tumor necrosis factor alpha and interferon gamma and MODS, as indicated by a decrease in arterial oxygen pressure (lung) and an increase in plasma concentrations of bilirubin and alanine aminotransferase (liver), creatinine and urea (kidney), lipase (pancreas), and creatine kinase (heart or skeletal muscle). There was also the expression of inducible nitric oxide synthase in these organs, circulatory failure, and 50% mortality. These effects were not observed after administration of PepG or LTA alone. Even a high dose of LTA (10 mg/kg) causes only circulatory failure but no MODS. Thus, our results demonstrate that the two bacterial wall components, PepG and LTA, work together to cause systemic inflammation and multiple systems failure associated with Gram-positive organisms. Images Fig. 2 PMID:7479784

  5. Failure to Manage Constant Change

    ERIC Educational Resources Information Center

    McDonald, Ann

    2010-01-01

    This study examines patterns of system failure (communication, typographic, material, economic, maintenance) and the resulting workarounds in signs that are intended to communicate frequently changing information in the built environment. The observed failures and workarounds in the communication of ephemeral data and the accompanying narratives…

  6. Periodontitis in Chronic Heart Failure.

    PubMed

    Fröhlich, Hanna; Herrmann, Kristina; Franke, Jennifer; Karimi, Alamara; Täger, Tobias; Cebola, Rita; Katus, Hugo A; Zugck, Christian; Frankenstein, Lutz

    2016-08-01

    Periodontal disease has been associated with an increased risk of cardiovascular events. The purpose of our study was to investigate whether a correlation between periodontitis and chronic heart failure exists, as well as the nature of the underlying cause. We enrolled 71 patients (mean age, 54 ± 13 yr; 56 men) who had stable chronic heart failure; all underwent complete cardiologic and dental evaluations. The periodontal screening index was used to quantify the degree of periodontal disease. We compared the findings to those in the general population with use of data from the 4th German Dental Health Survey. Gingivitis, moderate periodontitis, and severe periodontitis were present in 17 (24%), 17 (24%), and 37 (52%) patients, respectively. Severe periodontitis was more prevalent among chronic heart failure patients than in the general population. In contrast, moderate periodontitis was more prevalent in the general population (P <0.00001). The severity of periodontal disease was not associated with the cause of chronic heart failure or the severity of heart failure symptoms. Six-minute walking distance was the only independent predictor of severe periodontitis. Periodontal disease is highly prevalent in chronic heart failure patients regardless of the cause of heart failure. Prospective trials are warranted to clarify the causal relationship between both diseases.

  7. Periodontitis in Chronic Heart Failure

    PubMed Central

    Fröhlich, Hanna; Herrmann, Kristina; Franke, Jennifer; Karimi, Alamara; Täger, Tobias; Cebola, Rita; Katus, Hugo A.; Zugck, Christian

    2016-01-01

    Periodontal disease has been associated with an increased risk of cardiovascular events. The purpose of our study was to investigate whether a correlation between periodontitis and chronic heart failure exists, as well as the nature of the underlying cause. We enrolled 71 patients (mean age, 54 ± 13 yr; 56 men) who had stable chronic heart failure; all underwent complete cardiologic and dental evaluations. The periodontal screening index was used to quantify the degree of periodontal disease. We compared the findings to those in the general population with use of data from the 4th German Dental Health Survey. Gingivitis, moderate periodontitis, and severe periodontitis were present in 17 (24%), 17 (24%), and 37 (52%) patients, respectively. Severe periodontitis was more prevalent among chronic heart failure patients than in the general population. In contrast, moderate periodontitis was more prevalent in the general population (P <0.00001). The severity of periodontal disease was not associated with the cause of chronic heart failure or the severity of heart failure symptoms. Six-minute walking distance was the only independent predictor of severe periodontitis. Periodontal disease is highly prevalent in chronic heart failure patients regardless of the cause of heart failure. Prospective trials are warranted to clarify the causal relationship between both diseases. PMID:27547136

  8. STS-3 main parachute failure

    NASA Technical Reports Server (NTRS)

    Runkle, R.; Henson, K.

    1982-01-01

    A failure analysis of the parachute on the Space Transportation System 3 flight's solid rocket booster's is presented. During the reentry phase of the two Solid Rocket Boosters (SRBs), one 115 ft diameter main parachute failed on the right hand SRB (A12). This parachute failure caused the SRB to impact the Ocean at 110 ft/sec in lieu of the expected 3 parachute impact velocity of 88 ft/sec. This higher impact velocity relates directly to more SRB aft skirt and more motor case damage. The cause of the parachute failure, the potential risks of losing an SRB as a result of this failure, and recommendations to ensure that the probability of chute failures of this type in the future will be low are discussed.

  9. Technical Basis for Evaluating Software-Related Common-Cause Failures

    SciTech Connect

    Muhlheim, Michael David; Wood, Richard

    2016-04-01

    The instrumentation and control (I&C) system architecture at a nuclear power plant (NPP) incorporates protections against common-cause failures (CCFs) through the use of diversity and defense-in-depth. Even for well-established analog-based I&C system designs, the potential for CCFs of multiple systems (or redundancies within a system) constitutes a credible threat to defeating the defense-in-depth provisions within the I&C system architectures. The integration of digital technologies into the I&C systems provides many advantages compared to the aging analog systems with respect to reliability, maintenance, operability, and cost effectiveness. However, maintaining the diversity and defense-in-depth for both the hardware and software within themore » digital system is challenging. In fact, the introduction of digital technologies may actually increase the potential for CCF vulnerabilities because of the introduction of undetected systematic faults. These systematic faults are defined as a “design fault located in a software component” and at a high level, are predominately the result of (1) errors in the requirement specification, (2) inadequate provisions to account for design limits (e.g., environmental stress), or (3) technical faults incorporated in the internal system (or architectural) design or implementation. Other technology-neutral CCF concerns include hardware design errors, equipment qualification deficiencies, installation or maintenance errors, instrument loop scaling and setpoint mistakes.« less

  10. Do Learning Difficulties Differentiate Elementary Teachers' Attributional Patterns for Students' Academic Failure? A Comparison between Greek Regular and Special Education Teachers

    ERIC Educational Resources Information Center

    Vlachou, Anastasia; Eleftheriadou, Dimitra; Metallidou, Panayiota

    2014-01-01

    This study aimed to (a) investigate whether the presence of learning difficulties (LD) in primary school children differentiates Greek teachers' attributional patterns, emotional responses, expectations and evaluative feedback for the children's academic failures and (b) to examine possible differences between regular and special education…

  11. The Effect of Cavity Design on Fracture Resistance and Failure Pattern in Monolithic Zirconia Partial Coverage Restorations - An In vitro Study.

    PubMed

    Harsha, Madhavareddy Sri; Praffulla, Mynampati; Babu, Mandava Ramesh; Leneena, Gudugunta; Krishna, Tejavath Sai; Divya, G

    2017-05-01

    Cavity preparations of posterior teeth have been frequently associated with decreased fracture strength of the teeth. Choosing the correct indirect restoration and the cavity design when restoring the posterior teeth i.e., premolars was difficult as it involves aesthetic, biomechanical and anatomical considerations. To evaluate the fracture resistance and failure pattern of three different cavity designs restored with monolithic zirconia. Human maxillary premolars atraumatically extracted for orthodontic reasons were chosen. A total of 40 teeth were selected and divided into four groups (n=10). Group I-Sound teeth (control with no preparation). Group II-MOD Inlay, Group III-Partial Onlay, Group IV-Complete Onlay. Restorations were fabricated with monolithic partially sintered zirconia CAD (SAGEMAX- NexxZr). All the 30 samples were cemented using Multilink Automix (Ivoclar) and subjected to fracture resistance testing using Universal Testing Machine (UTM) (Instron) with a steel ball of 3.5 mm diameter at crosshead speed of 0.5 mm/minute. Stereomicroscope was used to evaluate the modes of failure of the fractured specimen. Fracture resistance was tested using parametric one way ANOVA test, unpaired t-test and Tukey test. Fracture patterns were assessed using non-parametric Chi-square test. Group IV (Complete Onlay) presented highest fracture resistance and showed statistical significant difference. Group II (MOD Inlay) and Group III (Partial Onlay) showed significantly lower values than the Group I (Sound teeth). However, Groups I, II and III presented no significant difference from each other. Coming to the modes of failure, Group II (MOD Inlay) and Group III (Partial Onlay) presented mixed type of failures; Group IV (Complete Onlay) demonstrated 70% Type I failures. Of the three cavity designs evaluated, Complete Onlay had shown a significant increase in the fracture resistance than the Sound teeth.

  12. Detonation Failure Thickness Measurement in AN Annular Geometry

    NASA Astrophysics Data System (ADS)

    Mack, D. B.; Petel, O. E.; Higgins, A. J.

    2007-12-01

    The failure thickness of neat nitromethane in aluminum confinement was measured using a novel experimental technique. The thickness was approximated in an annular geometry by the gap between a concentric aluminum tube and rod. This technique was motivated by the desire to have a periodic boundary condition in the direction orthogonal to the annulus thickness, rather than a free surface occurring in typical rectangular geometry experiments. This results in a two-dimensional charge analogous to previous failure thickness setups but with infinite effective width (i.e. infinite aspect ratio). Detonation propagation or failure was determined by the observation of failure patterns engraved on the aluminum rod by the passing detonation. Analysis of these engraved patterns provides a statistical measurement of the spatial density of failure waves. Failure was observed as far as 180 thicknesses downstream. The failure thickness was measured to be 1.45 mm±0.15 mm.

  13. Comprehensive electronic medical record implementation levels not associated with 30-day all-cause readmissions within Medicare beneficiaries with heart failure.

    PubMed

    Patterson, M E; Marken, P; Zhong, Y; Simon, S D; Ketcherside, W

    2014-01-01

    Regulatory standards for 30-day readmissions incentivize hospitals to improve quality of care. Implementing comprehensive electronic health record systems potentially decreases readmission rates by improving medication reconciliation at discharge, demonstrating the additional benefits of inpatient EHRs beyond improved safety and decreased errors. To compare 30-day all-cause readmission incidence rates within Medicare fee-for-service with heart failure discharged from hospitals with full implementation levels of comprehensive EHR systems versus those without. This retrospective cohort study uses data from the American Hospital Association Health IT survey and Medicare Part A claims to measure associations between hospital EHR implementation levels and beneficiary readmissions. Multivariable Cox regressions estimate the hazard ratio of 30-day all-cause readmissions within beneficiaries discharged from hospitals implementing comprehensive EHRs versus those without, controlling for beneficiary health status and hospital organizational factors. Propensity scores are used to account for selection bias. The proportion of heart failure patients with 30-day all-cause readmissions was 30%, 29%, and 32% for those discharged from hospitals with full, some, and no comprehensive EHR systems. Heart failure patients discharged from hospitals with fully implemented comprehensive EHRs compared to those with no comprehensive EHR systems had equivalent 30-day readmission incidence rates (HR = 0.97, 95% CI 0.73 - 1.3). Implementation of comprehensive electronic health record systems does not necessarily improve a hospital's ability to decrease 30-day readmission rates. Improving the efficiency of post-acute care will require more coordination of information systems between inpatient and ambulatory providers.

  14. Association of the Endobiont Double-Stranded RNA Virus LRV1 With Treatment Failure for Human Leishmaniasis Caused by Leishmania braziliensis in Peru and Bolivia

    PubMed Central

    Adaui, Vanessa; Lye, Lon-Fye; Akopyants, Natalia S.; Zimic, Mirko; Llanos-Cuentas, Alejandro; Garcia, Lineth; Maes, Ilse; De Doncker, Simonne; Dobson, Deborah E.; Arevalo, Jorge; Dujardin, Jean-Claude; Beverley, Stephen M.

    2016-01-01

    Cutaneous and mucosal leishmaniasis, caused in South America by Leishmania braziliensis, is difficult to cure by chemotherapy (primarily pentavalent antimonials [SbV]). Treatment failure does not correlate well with resistance in vitro, and the factors responsible for treatment failure in patients are not well understood. Many isolates of L. braziliensis (>25%) contain a double-stranded RNA virus named Leishmaniavirus 1 (LRV1), which has also been reported in Leishmania guyanensis, for which an association with increased pathology, metastasis, and parasite replication was found in murine models. Here we probed the relationship of LRV1 to drug treatment success and disease in 97 L. braziliensis–infected patients from Peru and Bolivia. In vitro cultures were established, parasites were typed as L. braziliensis, and the presence of LRV1 was determined by reverse transcription–polymerase chain reaction, followed by sequence analysis. LRV1 was associated significantly with an increased risk of treatment failure (odds ratio, 3.99; P = .04). There was no significant association with intrinsic SbV resistance among parasites, suggesting that treatment failure arises from LRV1-mediated effects on host metabolism and/or parasite survival. The association of LRV1 with clinical drug treatment failure could serve to guide more-effective treatment of tegumentary disease caused by L. braziliensis. PMID:26123565

  15. Immunohistochemical identification of prevalent right ventricular ischemia causing right heart failure in cases of pulmonary fat embolism.

    PubMed

    Fracasso, Tony; Karger, Bernd; Pfeiffer, Heidi; Sauerland, Cristina; Schmeling, Andreas

    2010-11-01

    Pulmonary fat embolism is a life-threatening event that may result to potentially determining right ventricular failure. Even if the pathophysiology of this phenomenon has been widely investigated, no immunohistochemical demonstration of right ventricular failure following pulmonary fat embolism has been reported till now. We performed an immunohistochemical investigation with the markers fibronectin and C5b-9 in 21 cases of polytrauma with bone fractures (study group-nine females and 12 males; mean age 64.6 years) compared to a control group of 21 forensic cases with various causes of death (nine females and 12 males; mean age 68.6 years). In each case at least one tissue slide from both cardiac ventricles (free wall of the right ventricle, anterior and/or posterior wall of the left ventricle) was available. The reactions were semi-quantitatively classified, and the two groups were compared. In the study group, the occurrence of ischemic changes at the right ventricle was significantly higher than in controls. The determining aspect, however, seems to be the prevalent ischemic lesion at the right ventricle compared to the left one. This may indicate the primary involvement of the right ventricle, thus, demonstrating a right ventricular failure.

  16. Lack of Evidence for Racial Disparity in 30-Day All-Cause Readmission Rate for Older US Veterans Hospitalized with Heart Failure.

    PubMed

    Kheirbek, Raya Elfadel; Wojtusiak, Janusz; Vlaicu, Sorina O; Alemi, Farrokh

    Heart failure is the leading cause for 30-day all-cause readmission. Although racial disparities in health care are well documented, their impact on 30-day all-cause readmission rate is inconclusive. We examined the impact of racial disparity on 30-day readmission for hospitalized patients with heart failure. This is a retrospective secondary data analysis for a large veteran cohort in 130 Veterans Affairs Medical Centers. Propensity scores were used to reduce differences in age, gender, survival days, and comorbidities in index hospitalization among 46 524 whites and 14 124 African Americans (AA). At index hospitalization, AA patients were younger (73.04 vs 67.10 years, t = -54.58, P < .000) and less likely to have myocardial infarcts (8.02% vs 9.80%, t = -6.36, P = .000), peripheral vascular disease (15.25% vs 22.51%, t = -18.68, P = .000), chronic obstructive pulmonary disease (39.59% vs 50.05%, t = -21.89, P < .000), and complicated diabetes (23.42% vs 26.24%, t = -6.73, P = .000). AA patients had lower mortality 30 days post-index hospitalization (3.51% vs 5.69%, t = -10.23, P = .000). In contrast, AA patients were more likely to have renal disease (44.03% vs 38.71%, t = 11.32, P < .000) and HIV/AIDS (1.56% vs 0.20%, t = 19.71, P < .000). The 30-day all-cause readmission rate before adjustments was 17.82% for AA patients versus 18.72% for white patients. There was no difference in the 2 rates after adjustments (18% vs 18%; odds of readmission = 1.002, z = 0.08, P = .937). In a large Department of Veterans Affairs (VA) cohort, white and AA veterans hospitalized for heart failure had similar 30-day all-cause readmission rates after adjustments were made for age, gender, survival days, and comorbidities. However, the 30-day all-cause mortality rate was higher for white patients than for AA patients. Future prospective studies are needed to validate results and test generalizability outside the VA system of care.

  17. 33 CFR 20.705 - Failure to appear.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Failure to appear. 20.705 Section....705 Failure to appear. The ALJ may enter a default under § 20.310 against a respondent threatening to... days or less after an order to show good cause, the respondent shows good cause for his or her failure...

  18. 33 CFR 20.705 - Failure to appear.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Failure to appear. 20.705 Section....705 Failure to appear. The ALJ may enter a default under § 20.310 against a respondent threatening to... days or less after an order to show good cause, the respondent shows good cause for his or her failure...

  19. 33 CFR 20.705 - Failure to appear.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Failure to appear. 20.705 Section....705 Failure to appear. The ALJ may enter a default under § 20.310 against a respondent threatening to... days or less after an order to show good cause, the respondent shows good cause for his or her failure...

  20. 33 CFR 20.705 - Failure to appear.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Failure to appear. 20.705 Section....705 Failure to appear. The ALJ may enter a default under § 20.310 against a respondent threatening to... days or less after an order to show good cause, the respondent shows good cause for his or her failure...

  1. 33 CFR 20.705 - Failure to appear.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Failure to appear. 20.705 Section....705 Failure to appear. The ALJ may enter a default under § 20.310 against a respondent threatening to... days or less after an order to show good cause, the respondent shows good cause for his or her failure...

  2. Apollo 15 main-parachute failure

    NASA Technical Reports Server (NTRS)

    Arabian, D. D.; Mechelay, J. E.

    1972-01-01

    In the investigation of the failure of one of the three main parachutes of the Apollo 15 spacecraft, which collapsed at approximately 1825 meters after operating properly from deployment at 3050 meters, three conditions considered to be possible causes of the failure were produced. The suspect conditions were the proximity of the forward heat shield that passed the spacecraft at approximately 1825 meters, the dumping of the reaction control system hypergolic propellants at approximately 1825 meters, and the failing of a riser link found on a recovered parachute. (The failed parachute was not recovered). The remaining two parachutes functioned as planned and averted a catastrophic failure. The conclusions concerning the cause of the failure are discussed.

  3. The influence of microstructure on the probability of early failure in aluminum-based interconnects

    NASA Astrophysics Data System (ADS)

    Dwyer, V. M.

    2004-09-01

    For electromigration in short aluminum interconnects terminated by tungsten vias, the well known "short-line" effect applies. In a similar manner, for longer lines, early failure is determined by a critical value Lcrit for the length of polygranular clusters. Any cluster shorter than Lcrit is "immortal" on the time scale of early failure where the figure of merit is not the standard t50 value (the time to 50% failures), but rather the total probability of early failure, Pcf. Pcf is a complex function of current density, linewidth, line length, and material properties (the median grain size d50 and grain size shape factor σd). It is calculated here using a model based around the theory of runs, which has proved itself to be a useful tool for assessing the probability of extreme events. Our analysis shows that Pcf is strongly dependent on σd, and a change in σd from 0.27 to 0.5 can cause an order of magnitude increase in Pcf under typical test conditions. This has implications for the web-based two-dimensional grain-growth simulator MIT/EmSim, which generates grain patterns with σd=0.27, while typical as-patterned structures are better represented by a σd in the range 0.4 - 0.6. The simulator will consequently overestimate interconnect reliability due to this particular electromigration failure mode.

  4. Analysis of underlying and multiple-cause mortality data: the life table methods.

    PubMed

    Moussa, M A

    1987-02-01

    The stochastic compartment model concepts are employed to analyse and construct complete and abbreviated total mortality life tables, multiple-decrement life tables for a disease, under the underlying and pattern-of-failure definitions of mortality risk, cause-elimination life tables, cause-elimination effects on saved population through the gain in life expectancy as a consequence of eliminating the mortality risk, cause-delay life tables designed to translate the clinically observed increase in survival time as the population gain in life expectancy that would occur if a treatment protocol was made available to the general population and life tables for disease dependency in multiple-cause data.

  5. Failure of endodontic treatment: The usual suspects.

    PubMed

    Tabassum, Sadia; Khan, Farhan Raza

    2016-01-01

    Inappropriate mechanical debridement, persistence of bacteria in the canals and apex, poor obturation quality, over and under extension of the root canal filling, and coronal leakage are some of the commonly attributable causes of failure. Despite the high success rate of endodontic treatment, failures do occur in a large number of cases and most of the times can be attributed to the already stated causes. With an ever increasing number of endodontic treatments being done each day, it has become imperative to avoid or minimize the most fundamental of reasons leading to endodontic failure. This paper reviews the most common causes of endodontic failure along with radiographic examples.

  6. Failure of endodontic treatment: The usual suspects

    PubMed Central

    Tabassum, Sadia; Khan, Farhan Raza

    2016-01-01

    Inappropriate mechanical debridement, persistence of bacteria in the canals and apex, poor obturation quality, over and under extension of the root canal filling, and coronal leakage are some of the commonly attributable causes of failure. Despite the high success rate of endodontic treatment, failures do occur in a large number of cases and most of the times can be attributed to the already stated causes. With an ever increasing number of endodontic treatments being done each day, it has become imperative to avoid or minimize the most fundamental of reasons leading to endodontic failure. This paper reviews the most common causes of endodontic failure along with radiographic examples. PMID:27011754

  7. Double knockout of pendrin and Na-Cl cotransporter (NCC) causes severe salt wasting, volume depletion, and renal failure.

    PubMed

    Soleimani, Manoocher; Barone, Sharon; Xu, Jie; Shull, Gary E; Siddiqui, Faraz; Zahedi, Kamyar; Amlal, Hassane

    2012-08-14

    The Na-Cl cotransporter (NCC), which is the target of inhibition by thiazides, is located in close proximity to the chloride-absorbing transporter pendrin in the kidney distal nephron. Single deletion of pendrin or NCC does not cause salt wasting or excessive diuresis under basal conditions, raising the possibility that these transporters are predominantly active during salt depletion or in response to excess aldosterone. We hypothesized that pendrin and NCC compensate for loss of function of the other under basal conditions, thereby masking the role that each plays in salt absorption. To test our hypothesis, we generated pendrin/NCC double knockout (KO) mice by crossing pendrin KO mice with NCC KO mice. Pendrin/NCC double KO mice displayed severe salt wasting and sharp increase in urine output under basal conditions. As a result, animals developed profound volume depletion, renal failure, and metabolic alkalosis without hypokalemia, which were all corrected with salt replacement. We propose that the combined inhibition of pendrin and NCC can provide a strong diuretic regimen without causing hypokalemia for patients with fluid overload, including patients with congestive heart failure, nephrotic syndrome, diuretic resistance, or generalized edema.

  8. Double knockout of pendrin and Na-Cl cotransporter (NCC) causes severe salt wasting, volume depletion, and renal failure

    PubMed Central

    Soleimani, Manoocher; Barone, Sharon; Xu, Jie; Shull, Gary E.; Siddiqui, Faraz; Zahedi, Kamyar; Amlal, Hassane

    2012-01-01

    The Na-Cl cotransporter (NCC), which is the target of inhibition by thiazides, is located in close proximity to the chloride-absorbing transporter pendrin in the kidney distal nephron. Single deletion of pendrin or NCC does not cause salt wasting or excessive diuresis under basal conditions, raising the possibility that these transporters are predominantly active during salt depletion or in response to excess aldosterone. We hypothesized that pendrin and NCC compensate for loss of function of the other under basal conditions, thereby masking the role that each plays in salt absorption. To test our hypothesis, we generated pendrin/NCC double knockout (KO) mice by crossing pendrin KO mice with NCC KO mice. Pendrin/NCC double KO mice displayed severe salt wasting and sharp increase in urine output under basal conditions. As a result, animals developed profound volume depletion, renal failure, and metabolic alkalosis without hypokalemia, which were all corrected with salt replacement. We propose that the combined inhibition of pendrin and NCC can provide a strong diuretic regimen without causing hypokalemia for patients with fluid overload, including patients with congestive heart failure, nephrotic syndrome, diuretic resistance, or generalized edema. PMID:22847418

  9. Ovarian function after autologous bone marrow transplantation in childhood: high-dose busulfan is a major cause of ovarian failure.

    PubMed

    Teinturier, C; Hartmann, O; Valteau-Couanet, D; Benhamou, E; Bougneres, P F

    1998-11-01

    We studied pubertal status and ovarian function in 21 girls aged 11-21 years who had earlier received 1.2-13 years (median 7 years) high-dose chemotherapy and autologous BMT without TBI for malignant tumors. Ten of them were given busulfan (600 mg/m2) and melphalan (140 mg/m2) with or without cyclophosphamide (3.6 g/m2). Eleven others did not receive busulfan. Twelve girls (57%) had clinical and hormonal evidence of ovarian failure. Among nine others who had completed normal puberty, six had normal gonadotropin levels, one had elevated gonadotropin levels and two had gonadotropin levels at the upper limit of normal. The 10 girls who received busulfan all developed severe and persistent ovarian failure. High-dose busulfan is therefore a major cause of ovarian failure even when given in the prepubertal period. These findings emphasize the need for long-term endocrine follow-up of these patients in order to initiate estrogen replacement therapy.

  10. High-Temperature Graphitization Failure of Primary Superheater Tube

    NASA Astrophysics Data System (ADS)

    Ghosh, D.; Ray, S.; Roy, H.; Mandal, N.; Shukla, A. K.

    2015-12-01

    Failure of boiler tubes is the main cause of unit outages of the plant, which further affects the reliability, availability and safety of the unit. So failure analysis of boiler tubes is absolutely essential to predict the root cause of the failure and the steps are taken for future remedial action to prevent the failure in near future. This paper investigates the probable cause/causes of failure of the primary superheater tube in a thermal power plant boiler. Visual inspection, dimensional measurement, chemical analysis, metallographic examination and hardness measurement are conducted as the part of the investigative studies. Apart from these tests, mechanical testing and fractographic analysis are also conducted as supplements. Finally, it is concluded that the superheater tube is failed due to graphitization for prolonged exposure of the tube at higher temperature.

  11. Paleolithic and Mediterranean Diet Pattern Scores Are Inversely Associated with All-Cause and Cause-Specific Mortality in Adults123

    PubMed Central

    Whalen, Kristine A; Judd, Suzanne; McCullough, Marjorie L; Flanders, W Dana; Hartman, Terryl J; Bostick, Roberd M

    2017-01-01

    Background: Poor diet quality is associated with a higher risk of many chronic diseases that are among the leading causes of death in the United States. It has been hypothesized that evolutionary discordance may account for some of the higher incidence and mortality from these diseases. Objective: We investigated associations of 2 diet pattern scores, the Paleolithic and the Mediterranean, with all-cause and cause-specific mortality in the REGARDS (REasons for Geographic and Racial Differences in Stroke) study, a longitudinal cohort of black and white men and women ≥45 y of age. Methods: Participants completed questionnaires, including a Block food-frequency questionnaire (FFQ), at baseline and were contacted every 6 mo to determine their health status. Of the analytic cohort (n = 21,423), a total of 2513 participants died during a median follow-up of 6.25 y. We created diet scores from FFQ responses and assessed their associations with mortality using multivariable Cox proportional hazards regression models adjusting for major risk factors. Results: For those in the highest relative to the lowest quintiles of the Paleolithic and Mediterranean diet scores, the multivariable adjusted HRs for all-cause mortality were, respectively, 0.77 (95% CI: 0.67, 0.89; P-trend < 0.01) and 0.63 (95% CI: 0.54, 0.73; P-trend < 0.01). The corresponding HRs for all-cancer mortality were 0.72 (95% CI: 0.55, 0.95; P-trend = 0.03) and 0.64 (95% CI: 0.48, 0.84; P-trend = 0.01), and for all-cardiovascular disease mortality they were 0.78 (95% CI: 0.61, 1.00; P-trend = 0.06) and HR: 0.68 (95% CI: 0.53, 0.88; P-trend = 0.01). Conclusions: Findings from this biracial prospective study suggest that diets closer to Paleolithic or Mediterranean diet patterns may be inversely associated with all-cause and cause-specific mortality. PMID:28179490

  12. A good time to panic? Premorbid and postmorbid panic disorder in heart failure affects cardiac and psychiatric cause admissions.

    PubMed

    Tully, Phillip J

    2015-04-01

    The authors sought to identify characteristics associated with premorbid and postmorbid panic disorder onset in relation to heart failure (HF) onset, and examine the effect on unplanned hospital admissions. In a two-stage screening process, 404 HF patients admitted to three hospitals in South Australia were referred for structured psychiatric interview when any of the following four criteria were met: (a) Patient Health Questionnaire≥10; (b) Generalized Anxiety Disorder Questionnaire≥7); (c) positive response to one-item panic attack screener; (d) or evidence of suicidality. A total of 73 referred HF patients (age 60.6±13.4, 47.9% female) were classified into three groups: premorbid panic disorder (27.4%), postmorbid panic disorder (24.7%), and no panic disorder (47.9%). Postmorbid panic disorder was associated with more psychiatric admissions and longer hospital stay in the 6 months prior to the index psychiatric assessment, and also in the 6 months after the index psychiatric assessment (all p<.05 unadjusted). In sensitivity analysis, years since panic disorder onset were associated with longer cardiac length of stay (β=.34, p=.03). Panic disorder onset in relation to HF diagnosis was associated with discrete patterns of hospital admissions for cardiac and psychiatric causes. © The Royal Australian and New Zealand College of Psychiatrists 2015.

  13. Patterns and causes of geographic variation in bat echolocation pulses.

    PubMed

    Jiang, Tinglei; Wu, Hui; Feng, Jiang

    2015-05-01

    Evolutionary biologists have a long-standing interest in how acoustic signals in animals vary geographically, because divergent ecology and sensory perception play an important role in speciation. Geographic comparisons are valuable in determining the factors that influence divergence of acoustic signals. Bats are social mammals and they depend mainly on echolocation pulses to locate prey, to navigate and to communicate. Mounting evidence shows that geographic variation of bat echolocation pulses is common, with a mean 5-10 kHz differences in peak frequency, and a high level of individual variation may be nested in this geographical variation. However, understanding the geographic variation of echolocation pulses in bats is very difficult, because of differences in sample and statistical analysis techniques as well as the variety of factors shaping the vocal geographic evolution. Geographic differences in echolocation pulses of bats generally lack latitudinal, longitudinal and elevational patterns, and little is known about vocal dialects. Evidence is accumulating to support the fact that geographic variation in echolocation pulses of bats may be caused by genetic drift, cultural drift, ecological selection, sexual selection and social selection. Future studies could relate geographic differences in echolocation pulses to social adaptation, vocal learning strategies and patterns of dispersal. In addition, new statistical techniques and acoustic playback experiments may help to illustrate the causes and consequences of the geographic evolution of echolocation pulse in bats. © 2015 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  14. Pill Properties that Cause Dysphagia and Treatment Failure

    PubMed Central

    Fields, Jeremy; Go, Jorge T.; Schulze, Konrad S.

    2015-01-01

    Background Pills (tablets and capsules) are widely used to administer prescription drugs or to take supplements such as vitamins. Unfortunately, little is known about how much effort it takes Americans to swallow these various pills. More specifically, it is not known to what extent hard-to-swallow pills might affect treatment outcomes (eg, interfering with adherence to prescribed medications or causing clinical complications). It is also unclear which properties (eg, size, shape, or surface texture) Americans prefer or reject for their pills. To learn more about these issues, we interviewed a small group of individuals. Methods We invited individuals in waiting rooms of our tertiary health care center to participate in structured interviews about their pill-taking habits and any problems they have swallowing pills. We inquired which pill properties they believed caused swallowing problems. Participants scored capsules and pills of representative size, shape, and texture for swallowing effort and reported their personal preferences. Results Of 100 successive individuals, 99 participants completed the interview (65% women, mean age = 41 years, range = 23-77 years). Eighty-three percent took pills daily (mean 4 pills/d; 56% of those pills were prescribed by providers). Fifty-four percent of participants replied yes to the question, "Did you ever have to swallow a solid medication that was too difficult?" Four percent recounted serious complications: 1% pill esophagitis, 1% pill impaction, and 2% stopped treatments (antibiotic and prenatal supplement) because they could not swallow the prescribed pills. Half of all participants routinely resorted to special techniques (eg, plenty of liquids or repeated or forceful swallows). Sixty-one percent of those having difficulties cited specific pill properties: 27% blamed size (20% of problems were caused by pills that were too large whereas 7% complained about pills that were too small to sense); 12% faulted rough surface

  15. Long-Term Exposure to Environmental Concentrations of the Pharmaceutical Ethynylestradiol Causes Reproductive Failure in Fish

    PubMed Central

    Nash, Jon P.; Kime, David E.; Van der Ven, Leo T. M.; Wester, Piet W.; Brion, François; Maack, Gerd; Stahlschmidt-Allner, Petra; Tyler, Charles R.

    2004-01-01

    Heightened concern over endocrine-disrupting chemicals is driven by the hypothesis that they could reduce reproductive success and affect wildlife populations, but there is little evidence for this expectation. The pharmaceutical ethynylestradiol (EE2) is a potent endocrine modulator and is present in the aquatic environment at biologically active concentrations. To investigate impacts on reproductive success and mechanisms of disruption, we exposed breeding populations (n = 12) of zebrafish (Danio rerio) over multiple generations to environmentally relevant concentrations of EE2. Life-long exposure to 5 ng/L EE2 in the F1 generation caused a 56% reduction in fecundity and complete population failure with no fertilization. Conversely, the same level of exposure for up to 40 days in mature adults in the parental F0 generation had no impact on reproductive success. Infertility in the F1 generation after life-long exposure to 5 ng/L EE2 was due to disturbed sexual differentiation, with males having no functional testes and either undifferentiated or inter-sex gonads. These F1 males also showed a reduced vitellogenic response when compared with F0 males, indicating an acclimation to EE2 exposure. Depuration studies found only a partial recovery in reproductive capacity after 5 months. Significantly, even though the F1 males lacked functional testes, they showed male-pattern reproductive behavior, inducing the spawning act and competing with healthy males to disrupt fertilization. Endocrine disruption is therefore likely to affect breeding dynamics and reproductive success in group-spawning fish. Our findings raise major concerns about the population-level impacts for wildlife of long-term exposure to low concentrations of estrogenic endocrine disruptors. PMID:15579420

  16. Rate-weakening friction characterizes both slow sliding and catastrophic failure of landslides

    PubMed Central

    Handwerger, Alexander L.; Rempel, Alan W.; Skarbek, Rob M.; Roering, Joshua J.; Hilley, George E.

    2016-01-01

    Catastrophic landslides cause billions of dollars in damages and claim thousands of lives annually, whereas slow-moving landslides with negligible inertia dominate sediment transport on many weathered hillslopes. Surprisingly, both failure modes are displayed by nearby landslides (and individual landslides in different years) subjected to almost identical environmental conditions. Such observations have motivated the search for mechanisms that can cause slow-moving landslides to transition via runaway acceleration to catastrophic failure. A similarly diverse range of sliding behavior, including earthquakes and slow-slip events, occurs along tectonic faults. Our understanding of these phenomena has benefitted from mechanical treatments that rely upon key ingredients that are notably absent from previous landslide descriptions. Here, we describe landslide motion using a rate- and state-dependent frictional model that incorporates a nonlocal stress balance to account for the elastic response to gradients in slip. Our idealized, one-dimensional model reproduces both the displacement patterns observed in slow-moving landslides and the acceleration toward failure exhibited by catastrophic events. Catastrophic failure occurs only when the slip surface is characterized by rate-weakening friction and its lateral dimensions exceed a critical nucleation length h* that is shorter for higher effective stresses. However, landslides that are extensive enough to fall within this regime can nevertheless slide slowly for months or years before catastrophic failure. Our results suggest that the diversity of slip behavior observed during landslides can be described with a single model adapted from standard fault mechanics treatments. PMID:27573836

  17. Rate-weakening friction characterizes both slow sliding and catastrophic failure of landslides.

    PubMed

    Handwerger, Alexander L; Rempel, Alan W; Skarbek, Rob M; Roering, Joshua J; Hilley, George E

    2016-09-13

    Catastrophic landslides cause billions of dollars in damages and claim thousands of lives annually, whereas slow-moving landslides with negligible inertia dominate sediment transport on many weathered hillslopes. Surprisingly, both failure modes are displayed by nearby landslides (and individual landslides in different years) subjected to almost identical environmental conditions. Such observations have motivated the search for mechanisms that can cause slow-moving landslides to transition via runaway acceleration to catastrophic failure. A similarly diverse range of sliding behavior, including earthquakes and slow-slip events, occurs along tectonic faults. Our understanding of these phenomena has benefitted from mechanical treatments that rely upon key ingredients that are notably absent from previous landslide descriptions. Here, we describe landslide motion using a rate- and state-dependent frictional model that incorporates a nonlocal stress balance to account for the elastic response to gradients in slip. Our idealized, one-dimensional model reproduces both the displacement patterns observed in slow-moving landslides and the acceleration toward failure exhibited by catastrophic events. Catastrophic failure occurs only when the slip surface is characterized by rate-weakening friction and its lateral dimensions exceed a critical nucleation length [Formula: see text] that is shorter for higher effective stresses. However, landslides that are extensive enough to fall within this regime can nevertheless slide slowly for months or years before catastrophic failure. Our results suggest that the diversity of slip behavior observed during landslides can be described with a single model adapted from standard fault mechanics treatments.

  18. Metabolomic does not predict response to cardiac resynchronization therapy in patients with heart failure.

    PubMed

    Padeletti, Luigi; Modesti, Pietro A; Cartei, Stella; Checchi, Luca; Ricciardi, Giuseppe; Pieragnolia, Paolo; Sacchi, Stefania; Padeletti, Margherita; Alterini, Brunetto; Pantaleo, Pietro; Hu, Xiaoyu; Tenori, Leonardo; Luchinat, Claudio

    2014-04-01

    Metabolomic, a systematic study of metabolites, may be a useful tool in understanding the pathological processes that underlie the occurrence and progression of a disease. We hypothesized that metabolomic would be helpful in assessing a specific pattern in heart failure patients, also according to the underlining causes and in defining, prior to device implantation, the responder and nonresponder patient to cardiac resynchronization therapy (CRT). In this prospective study, blood and urine samples were collected from 32 heart failure patients who underwent CRT. Clinical, electrocardiography and echocardiographic evaluation was performed in each patient before CRT and after 6 months of follow-up. Thirty-nine age and sex-matched healthy individuals were chosen as control group. For each sample, 1H-NMR spectra, Nuclear Overhauser Enhancement Spectroscopy, Carr-Purcell-Meiboom-Gill and diffusion edited spectra were measured. A different metabolomic fingerprint was demonstrated in heart failure patients compared to healthy controls with high accuracy level. Metabolomics fingerprint was similar between patients with ischemic and nonischemic dilated cardiomyopathy. At 6-month follow-up, metabolomic fingerprint was different from baseline. At follow-up, heart failure patients’ metabolomic fingerprint remained significantly different from that of healthy controls, and accuracy of cause discrimination remained low. Responders and nonresponders had a similar metabolic fingerprint at baseline and after 6 months of CRT. It is possible to identify a metabolomic fingerprint characterizing heart failure patients candidate to CRT, it is independent of the different causes of the disease and it is not predictive of the response to CRT.

  19. Survey of Failure in Engineering Education and Industry

    NASA Astrophysics Data System (ADS)

    Arimitsu, Yutaka; Yagi, Hidetsugu

    Students have failure experiences in the project-based learning but they do not profess their experiences. On the other hand, failures and accidents, in the industrial world, are analyzed frequently, and a knowledge data base on failure and QC activities have been introduced. To turn failure experience in education to advantage, the authors survey the properties of failures in project based learning and views of students, teachers and managers of design divisions in companies. Teachers and students regard failure experiences as instructive and acceptable. The typical causes of failure in educational institutions are luck of skill in manufacturing and inadequate planning, which are minor causes of failure in the industry. To establish a knowledge data base on failure in educational institutions, properties of failure in education should be taken into account.

  20. Reduced ovulation rate, failure to be mated and fertilization failure/embryo loss are the underlying causes of poor reproductive performance in juvenile ewes.

    PubMed

    Edwards, Sara J; Smaill, Bronwyn; O'Connell, Anne R; Johnstone, Peter D; Stevens, David R; Quirke, Laurel D; Farquhar, Philip A; Juengel, Jennifer L

    2016-04-01

    A ewe that is mated as a juvenile (producing a lamb at 1 year of age) will produce an average of only 0.6 lambs to weaning, compared to an average of 1.2 lambs in adult ewes. Understanding the underlying causes of this low reproductive efficiency and designing methods to improve or mitigate these effects could potentially increase adoption of mating juvenile ewes. In Experiment 1, 2 Cohorts of ewes, born a year apart, were mated in order to lamb at 1 and 2 years of age and the performance of the ewes at each age was compared. Onset of puberty, mating by the fertile ram, ovulation rate, early pregnancy (day 30-35) litter size, number of lambs born and number of lambs weaned were measured. In juvenile ewes, by day 35 of pregnancy, 43% of ova had failed to become a viable embryo and this early loss was the largest contributor to the poor reproductive performance observed. Compared with young adult ewes, ovulation rate was lower (p<0.001), fewer ova were exposed to sperm (p<0.001) and fertilization failure/embryo loss was increased (p<0.001) in juveniles. In Experiment 2, the early pregnancy litter size of juveniles was shown to be greater (p<0.001) in those ewes with a greater ovulation rate (p<0.001). Attaining puberty prior to introduction of the fertile ram was associated with an increased pregnancy rate (p<0.001). In juvenile ewes, failure to mate with the ram, lower ovulation rate and increased fertilisation failure/embryo loss underlie their poor reproductive performance. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Effectiveness of Back Massage on Sleep Pattern among Patients with Congestive Cardiac Failure.

    PubMed

    Sable, Amol; Sivabalan, Thangaraj; Shetti, Akshaya Narayan

    2017-01-01

    Sleep plays an important role in congestive cardiac failure (CCF). Back massage reduces anxiety, discomfort, and physical suffering in CCF patients. Study objective is to assess sleep pattern in CCF patients before and after back massage. A quasi-experimental study was conducted in Pravara Rural hospital, Loni, India over 4 months in 2016. Thirty CCF patients were included in the study with purposive sampling. Nurse investigator performed 20-min back massage thrice daily, 5 min for each step from the day of admission till discharge. In back massage, effleurage, stroking, kneading, and assessment of effectiveness was recorded using the Pittsburg sleep quality index. Thirty CCF patients were included, out of which individuals aged >65, 56-65, and 35-45 years age group were 40%, 24%, and 13%, respectively. Twenty-four had left and 6 had right heart failure. Distribution of mean and standard deviation of pretest for sleep quality was 9.50 (3.14), indicating poor sleep quality. Posttest, the mean score was 4.47 (0.89), indicating good quality sleep. Eleven patients had >8 h of sleep, 15 patients had 6-8 h of sleep, whereas 4 patients had less than 6 h of sleep pretest. Posttest, 22 patients had >8 h and the remaining had 6-8 h of sleep. Back massage technique is safe and cost-effective in CCF patients, by which the quality and duration of sleep is improved. It can be a part of the standard treatment.

  2. Evidence of an emerging levee failure mechanism causing disastrous floods in Italy

    NASA Astrophysics Data System (ADS)

    Orlandini, Stefano; Moretti, Giovanni; Albertson, John D.

    2015-10-01

    A levee failure occurred along the Secchia River, Northern Italy, on 19 January 2014, resulting in flood damage in excess of $500 million. In response to this failure, immediate surveillance of other levees in the region led to the identification of a second breach developing on the neighboring Panaro River, where rapid mitigation efforts were successful in averting a full levee failure. The paired breach events that occurred along the Secchia and Panaro Rivers provided an excellent window on an emerging levee failure mechanism. In the Secchia River, by combining the information content of photographs taken from helicopters in the early stage of breach development and 10 cm resolution aerial photographs taken in 2010 and 2012, animal burrows were found to exist in the precise levee location where the breach originated. In the Panaro River, internal erosion was observed to occur at a location where a crested porcupine den was known to exist and this erosion led to the collapse of the levee top. This paper uses detailed numerical modeling of rainfall, river flow, and variably saturated flow in the levee to explore the hydraulic and geotechnical mechanisms that were triggered along the Secchia and Panaro Rivers by activities of burrowing animals leading to levee failures. As habitats become more fragmented and constrained along river corridors, it is possible that this failure mechanism could become more prevalent and, therefore, will demand greater attention in both the design and maintenance of earthen hydraulic structures as well as in wildlife management.

  3. Evidence of an emerging levee failure mechanism causing disastrous floods in Italy

    NASA Astrophysics Data System (ADS)

    Orlandini, Stefano; Moretti, Giovanni; Albertson, John

    2017-04-01

    A levee failure occurred along the Secchia River, Northern Italy, on January 19, 2014, resulting in flood damage in excess of 500 Million. In response to this failure, immediate surveillance of other levees in the region led to the identification of a second breach developing on the neighboring Panaro River, where rapid mitigation efforts were successful in averting a full levee failure. The paired breach events that occurred along the Secchia and Panaro Rivers provided an excellent window on an emerging levee failure mechanism. In the Secchia River, by combining the information content of photographs taken from helicopters in the early stage of breach development and 10-cm resolution aerial photographs taken in 2010 and 2012, animal burrows were found to exist in the precise levee location where the breach originated. In the Panaro River, internal erosion was observed to occur at a location where a crested porcupine den was known to exist and this erosion led to the collapse of the levee top. This paper uses detailed numerical modeling of rainfall, river flow, and variably saturated flow in the levee to explore the hydraulic and geotechnical mechanisms that were triggered along the Secchia and Panaro Rivers by activities of burrowing animals leading to levee failures. As habitats become more fragmented and constrained along river corridors it is possible that this failure mechanism could become more prevalent and, therefore, will demand greater attention in both the design and maintenance of earthen hydraulic structures as well as in wildlife management.

  4. Analyses of Transistor Punchthrough Failures

    NASA Technical Reports Server (NTRS)

    Nicolas, David P.

    1999-01-01

    The failure of two transistors in the Altitude Switch Assembly for the Solid Rocket Booster followed by two additional failures a year later presented a challenge to failure analysts. These devices had successfully worked for many years on numerous missions. There was no history of failures with this type of device. Extensive checks of the test procedures gave no indication for a source of the cause. The devices were manufactured more than twenty years ago and failure information on this lot date code was not readily available. External visual exam, radiography, PEID, and leak testing were performed with nominal results Electrical testing indicated nearly identical base-emitter and base-collector characteristics (both forward and reverse) with a low resistance short emitter to collector. These characteristics are indicative of a classic failure mechanism called punchthrough. In failure analysis punchthrough refers to an condition where a relatively low voltage pulse causes the device to conduct very hard producing localized areas of thermal runaway or "hot spots". At one or more of these hot spots, the excessive currents melt the silicon. Heavily doped emitter material diffuses through the base region to the collector forming a diffusion pipe shorting the emitter to base to collector. Upon cooling, an alloy junction forms between the pipe and the base region. Generally, the hot spot (punch-through site) is under the bond and no surface artifact is visible. The devices were delidded and the internal structures were examined microscopically. The gold emitter lead was melted on one device, but others had anomalies in the metallization around the in-tact emitter bonds. The SEM examination confirmed some anomalies to be cosmetic defects while other anomalies were artifacts of the punchthrough site. Subsequent to these analyses, the contractor determined that some irregular testing procedures occurred at the time of the failures heretofore unreported. These testing

  5. Hypercalcemia with renal failure.

    PubMed

    Bhavani, Nisha; Praveen, Valiyaparambil Pavithran; Jayakumar, Rohinivilasam Vasukutty; Nair, Vasantha; Muraleedharan, Mangath; Kuma, Harish; Unnikrishnan, Ambika Gopalakrishnan; Menon, Vadayath Usha

    2012-06-01

    We report a cse of nephrocalcinosis with renal failure which on evaluation was found to have hypercalcemia. Further investigations showed an inappropriately normal intact parathormone (iPTH) and 1,25 dihydroxy-vitamin D level in the setting of renal failure. Probing for a cause of non-PTH mediated hypercalcemia led to the diagnosis of sarcoidosis. Treatment with glucocorticoids could partially reverse the renal failure and control the hypercalcemia. This case illustrates the importance of careful interpretation of laboratory parameters especially levels of iPTH and vitamin D metabolites in renal failure.

  6. Factors influencing development of cracking-sliding failures of loess across the eastern Huangtu Plateau of China

    NASA Astrophysics Data System (ADS)

    Li, Yanrong; Mao, Jiarui; Xiang, Xiqiong; Mo, Ping

    2018-04-01

    Loess is a porous, weakly cemented, and unsaturated Quaternary sediment deposited by the wind in arid and semiarid regions. Loess is widely and thickly distributed in China, making the Huangtu Plateau the largest bulk accumulation of loess on Earth. However, the fragile geoenvironment in the loess areas of China causes frequent and various geohazards, such as cracking-sliding failure (beng-hua in Chinese), which is a typical geohazard that causes the largest number of casualties each year. This study investigates the main influencing factors and development patterns of cracking-sliding failure of loess to help prevent its occurrence and reduce losses effectively. The following conclusions are derived from this study: (1) cracking-sliding failures mostly take place in rectilinear slopes, convex slopes, slopes with gradients greater than 60°, slopes with heights of 5 to 40 m, and slopes mostly exposed to sunlight with aspects of 180 to 270°; (2) cracking-sliding failures occur mostly from 10 pm to 4 am and mainly in the rainy season (July to September) and in the freeze-thaw season (March to April); and (3) highly intense human activities in the region correspond to a high possibility of cracking-sliding failures.

  7. Patterns of failure after postoperative radiotherapy for incompletely resected (R1) non-small cell lung cancer: implications for radiation target volume design.

    PubMed

    Olszyna-Serementa, Marta; Socha, Joanna; Wierzchowski, Marek; Kępka, Lucyna

    2013-05-01

    Overall survival (OS) and pattern of failure in R1-resected non-small cell lung cancer (NSCLC) patients treated with 3D-planned postoperative radiotherapy (PORT) was retrospectively evaluated. The outcomes and patterns of failure in patients with (+) and without (-) extracapsular nodal extension (ECE) were compared and analyzed with respect to the radiation target volume design. Eighty R1-resected (37 ECE+ and 43 ECE-) patients received PORT (60Gy, 2Gy daily) between 2002 and 2011. Patients with N2 disease received limited elective nodal irradiation (ENI); for pN0-1 disease the use of ENI was optional. Among ECE- (extranodal-R1) patients there were 35 pN0-1 and eight pN2 cases; in pN0-1 patients, patterns of failure and outcomes were analyzed with respect to the use of ENI. Loco-regional failure (LRF) was defined as in-field relapse; isolated nodal failure (INF) was defined as out-of-field regional nodal recurrence occurring without LRF, irrespective of distant metastases. The actuarial 3-year OS rate was 36.3% (median: 30 months). Three-year OS rates in the ECE- and ECE+ group were 40.4% and 31.4%, with median OS of 31 and 24 months, respectively (p=0.43). In multivariate analysis, the presence of ECE was correlated with OS (HR=3.02; 95% CI: 1.00-9.16; p=0.05). Three-year cumulative incidence of LRF (CILRF) was 14.5% and 15.5% in the ECE- and ECE+ groups, respectively (p=0.98). Three-year cumulative incidence of INF (CIINF) was 14.1% in the ECE- group and 11.1% in the ECE+ group (p=0.76). For pN0-1 patients treated with and without ENI (13 and 22 patients) 3-year CILRF rates were 7.7% and 20.8%, respectively (p=0.20); 3-year CIINF rates were 9.1% and 16.3%, respectively (p=0.65). PORT resulted in a relatively good survival of R1-resected NSCLC patients. Relatively high incidence of INF was found in both ECE+ and ECE- patients. For ECE+ patients, treated with limited ENI, distant failure remains a major concern, so the design of ENI fields seems of lesser

  8. Respiratory failure in diabetic ketoacidosis.

    PubMed

    Konstantinov, Nikifor K; Rohrscheib, Mark; Agaba, Emmanuel I; Dorin, Richard I; Murata, Glen H; Tzamaloukas, Antonios H

    2015-07-25

    Respiratory failure complicating the course of diabetic ketoacidosis (DKA) is a source of increased morbidity and mortality. Detection of respiratory failure in DKA requires focused clinical monitoring, careful interpretation of arterial blood gases, and investigation for conditions that can affect adversely the respiration. Conditions that compromise respiratory function caused by DKA can be detected at presentation but are usually more prevalent during treatment. These conditions include deficits of potassium, magnesium and phosphate and hydrostatic or non-hydrostatic pulmonary edema. Conditions not caused by DKA that can worsen respiratory function under the added stress of DKA include infections of the respiratory system, pre-existing respiratory or neuromuscular disease and miscellaneous other conditions. Prompt recognition and management of the conditions that can lead to respiratory failure in DKA may prevent respiratory failure and improve mortality from DKA.

  9. Chloroquine-induced cardiomyopathy: a reversible cause of heart failure.

    PubMed

    Yogasundaram, Haran; Hung, Whitney; Paterson, Ian D; Sergi, Consolato; Oudit, Gavin Y

    2018-06-01

    Chloroquine (CQ) and hydroxychloroquine (HCQ) are anti-rheumatic medications frequently used in the treatment of connective tissue disorders. We present the case of a 45-year-old woman with CQ-induced cardiomyopathy leading to severe heart failure. Electrocardiographic abnormalities included bifascicular block, while structural disease consisted of severe biventricular and biatrial hypertrophy. Appropriate diagnosis via endomyocardial biopsy led to cessation of CQ and subsequent dramatic improvement in symptoms and structural heart disease. Cardiac toxicity is an under-recognized adverse effect of CQ/HCQ leading to cardiomyopathy with concentric hypertrophy and conduction abnormalities, with the potential for significant morbidity and mortality. Predisposing factors for CQ/HCQ-induced cardiomyopathy have been proposed. CQ/HCQ cardiomyopathy is a phenocopy of Fabry disease, and α-galactosidase A polymorphism may account for some heterogeneity of disease presentation. © 2018 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.

  10. Update on Common-Cause Failure Experience and Mitigation Practices

    SciTech Connect

    Wood, Richard Thomas; Muhlheim, Michael David; Pullum, Laura L

    2014-04-01

    Experience in other industries has shown that digital technology can provide substantial benefits in terms of performance and reliability. However, the U.S. nuclear power industry has been slow to adopt the technology extensively in its instrumentation and control (I&C) applications because of inhibiting factors such as regulatory uncertainty, insufficient technological experience base, implementation complexity, limited availability of nuclear-qualified products and vendors, and inadequate definition of modernization cost recapture. Although there have been examples of digital technology usage in the nuclear power industry, challenges to the qualification of digital technology for high-integrity nuclear power plant (NPP) applications have severely constrained moremore » widespread progress in achieving the benefits that are possible through the transition to digital. The U.S. Department of Energy (DOE) Office of Nuclear Energy (NE) established the Advanced Sensors and Instrumentation (ASI) technology area under the Nuclear Energy Enabling Technologies (NEET) Program to coordinate the instrumentation and controls (I&C) research across DOE NE and to identify and lead efforts to address common needs. As part of the NEET ASI research program, the Digital Technology Qualification project was established. Under this project, the Oak Ridge National Laboratory (ORNL) is leading the investigation into mitigation of digital common-cause failure (CCF) vulnerabilities for nuclear-qualified applications. This technical report documents updated and expanded findings from research activities by ORNL. Specifically, the report describes CCF experience in the nuclear and nonnuclear industries, identifies the state of the practice for CCF mitigation through key examples, and presents conclusions from the determination of knowledge gaps.« less

  11. Reliability enhancement of APR + diverse protection system regarding common cause failures

    SciTech Connect

    Oh, Y. G.; Kim, Y. M.; Yim, H. S.

    2012-07-01

    The Advanced Power Reactor Plus (APR +) nuclear power plant design has been developed on the basis of the APR1400 (Advanced Power Reactor 1400 MWe) to further enhance safety and economics. For the mitigation of Anticipated Transients Without Scram (ATWS) as well as Common Cause Failures (CCF) within the Plant Protection System (PPS) and the Emergency Safety Feature - Component Control System (ESF-CCS), several design improvement features have been implemented for the Diverse Protection System (DPS) of the APR + plant. As compared to the APR1400 DPS design, the APR + DPS has been designed to provide the Safety Injectionmore » Actuation Signal (SIAS) considering a large break LOCA accident concurrent with the CCF. Additionally several design improvement features, such as channel structure with redundant processing modules, and changes of system communication methods and auto-system test methods, are introduced to enhance the functional reliability of the DPS. Therefore, it is expected that the APR + DPS can provide an enhanced safety and reliability regarding possible CCF in the safety-grade I and C systems as well as the DPS itself. (authors)« less

  12. Lipotoxicity Causes Multisystem Organ Failure and Exacerbates Acute Pancreatitis in Obesity

    PubMed Central

    Navina, Sarah; Acharya, Chathur; DeLany, James P.; Orlichenko, Lidiya S.; Baty, Catherine J.; Shiva, Sruti S.; Durgampudi, Chandra; Karlsson, Jenny M.; Lee, Kenneth; Bae, Kyongtae T.; Furlan, Alessandro; Behari, Jaideep; Liu, Shiguang; McHale, Teresa; Nichols, Larry; Papachristou, Georgios Ioannis; Yadav, Dhiraj; Singh, Vijay P.

    2012-01-01

    Obesity increases the risk of adverse outcomes during acute critical illnesses such as burns, severe trauma, and acute pancreatitis. Although individuals with more body fat and higher serum cytokines and lipase are more likely to experience problems, the roles that these characteristics play are not clear. We used severe acute pancreatitis as a representative disease to investigate the effects of obesity on local organ function and systemic processes. In obese humans, we found that an increase in the volume of intrapancreatic adipocytes was associated with more extensive pancreatic necrosis during acute pancreatitis and that acute pancreatitis was associated with multisystem organ failure in obese individuals. In vitro studies of pancreatic acinar cells showed that unsaturated fatty acids were proinflammatory, releasing intracellular calcium, inhibiting mitochondrial complexes I and V, and causing necrosis. Saturated fatty acids had no such effects. Inhibition of lipolysis in obese (ob/ob) mice with induced pancreatitis prevented a rise in serum unsaturated fatty acids and prevented renal injury, lung injury, systemic inflammation, hypocalcemia, reduced pancreatic necrosis, and mortality. Thus, therapeutic approaches that target unsaturated fatty acid–mediated lipotoxicity may reduce adverse outcomes in obese patients with critical illnesses such as severe acute pancreatitis. PMID:22049070

  13. Association of the Endobiont Double-Stranded RNA Virus LRV1 With Treatment Failure for Human Leishmaniasis Caused by Leishmania braziliensis in Peru and Bolivia.

    PubMed

    Adaui, Vanessa; Lye, Lon-Fye; Akopyants, Natalia S; Zimic, Mirko; Llanos-Cuentas, Alejandro; Garcia, Lineth; Maes, Ilse; De Doncker, Simonne; Dobson, Deborah E; Arevalo, Jorge; Dujardin, Jean-Claude; Beverley, Stephen M

    2016-01-01

    Cutaneous and mucosal leishmaniasis, caused in South America by Leishmania braziliensis, is difficult to cure by chemotherapy (primarily pentavalent antimonials [Sb(V)]). Treatment failure does not correlate well with resistance in vitro, and the factors responsible for treatment failure in patients are not well understood. Many isolates of L. braziliensis (>25%) contain a double-stranded RNA virus named Leishmaniavirus 1 (LRV1), which has also been reported in Leishmania guyanensis, for which an association with increased pathology, metastasis, and parasite replication was found in murine models. Here we probed the relationship of LRV1 to drug treatment success and disease in 97 L. braziliensis-infected patients from Peru and Bolivia. In vitro cultures were established, parasites were typed as L. braziliensis, and the presence of LRV1 was determined by reverse transcription-polymerase chain reaction, followed by sequence analysis. LRV1 was associated significantly with an increased risk of treatment failure (odds ratio, 3.99; P = .04). There was no significant association with intrinsic Sb(V) resistance among parasites, suggesting that treatment failure arises from LRV1-mediated effects on host metabolism and/or parasite survival. The association of LRV1 with clinical drug treatment failure could serve to guide more-effective treatment of tegumentary disease caused by L. braziliensis. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  14. Heart failure and sudden cardiac death in heritable thoracic aortic disease caused by pathogenic variants in the SMAD3 gene.

    PubMed

    Backer, Julie De; Braverman, Alan C

    2018-05-01

    Predominant cardiovascular manifestations in the spectrum of Heritable Thoracic Aortic Disease include by default aortic root aneurysms- and dissections, which may be associated with aortic valve disease. Mitral- and tricuspid valve prolapse are other commonly recognized features. Myocardial disease, characterized by heart failure and/or malignant arrhythmias has been reported in humans and in animal models harboring pathogenic variants in the Fibrillin1 gene. Description of clinical history of three cases from one family in Ghent (Belgium) and one family in St. Louis (US). We report on three cases from two families presenting end-stage heart failure (in two) and lethal arrhythmias associated with moderate left ventricular dilatation (in one). All three cases harbor a pathogenic variant in the SMAD3 gene, known to cause aneurysm osteoarthritis syndrome, Loeys-Dietz syndrome type 3 or isolated Heritable Thoracic Aortic Disease. These unusual presentations warrant awareness for myocardial disease in patients harboring pathogenic variants in genes causing Heritable Thoracic Aortic Disease and indicate the need for prospective studies in larger cohorts. © 2018 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals, Inc.

  15. Does state boredom cause failures of attention? Examining the relations between trait boredom, state boredom, and sustained attention.

    PubMed

    Hunter, Andrew; Eastwood, John D

    2016-08-10

    Boredom is an important personal and social problem, but the phenomena itself remains poorly understood. Recent work has shown that boredom is highly related to attention, and that this relationship may be instrumental in revealing boredom's causes and consequences. In this paper, experimental findings on trait boredom, state boredom, and sustained attention performance are presented. We demonstrate that trait boredom uniquely predicts sustained attention performance, over and above depression and self-report attention problems. We also present exploratory findings consistent with the claim that attention failures may cause boredom and that sustained attention tasks may themselves be boring. Discussion of each of these findings, and potential ramifications for cognitive research as a whole, is included.

  16. Root Cause Investigation of Lead-Free Solder Joint Interfacial Failures After Multiple Reflows

    NASA Astrophysics Data System (ADS)

    Li, Yan; Hatch, Olen; Liu, Pilin; Goyal, Deepak

    2017-03-01

    Solder joint interconnects in three-dimensional (3D) packages with package stacking configurations typically must undergo multiple reflow cycles during the assembly process. In this work, interfacial open joint failures between the bulk solder and the intermetallic compound (IMC) layer were found in Sn-Ag-Cu (SAC) solder joints connecting a small package to a large package after multiple reflow reliability tests. Systematic progressive 3D x-ray computed tomography experiments were performed on both incoming and assembled parts to reveal the initiation and evolution of the open failures in the same solder joints before and after the reliability tests. Characterization studies, including focused ion beam cross-sections, scanning electron microscopy, and energy-dispersive x-ray spectroscopy, were conducted to determine the correlation between IMC phase transformation and failure initiation in the solder joints. A comprehensive failure mechanism, along with solution paths for the solder joint interfacial failures after multiple reflow cycles, is discussed in detail.

  17. Testicular failure

    MedlinePlus

    ... Testicular failure occurs when the testicles cannot produce sperm or male hormones, such as testosterone. Causes Testicular ... semen analysis to examine the number of healthy sperm you are producing. Sometimes, an ultrasound of the ...

  18. Spacecraft Parachute Recovery System Testing from a Failure Rate Perspective

    NASA Technical Reports Server (NTRS)

    Stewart, Christine E.

    2013-01-01

    Spacecraft parachute recovery systems, especially those with a parachute cluster, require testing to identify and reduce failures. This is especially important when the spacecraft in question is human-rated. Due to the recent effort to make spaceflight affordable, the importance of determining a minimum requirement for testing has increased. The number of tests required to achieve a mature design, with a relatively constant failure rate, can be estimated from a review of previous complex spacecraft recovery systems. Examination of the Apollo parachute testing and the Shuttle Solid Rocket Booster recovery chute system operation will clarify at which point in those programs the system reached maturity. This examination will also clarify the risks inherent in not performing a sufficient number of tests prior to operation with humans on-board. When looking at complex parachute systems used in spaceflight landing systems, a pattern begins to emerge regarding the need for a minimum amount of testing required to wring out the failure modes and reduce the failure rate of the parachute system to an acceptable level for human spaceflight. Not only a sufficient number of system level testing, but also the ability to update the design as failure modes are found is required to drive the failure rate of the system down to an acceptable level. In addition, sufficient data and images are necessary to identify incipient failure modes or to identify failure causes when a system failure occurs. In order to demonstrate the need for sufficient system level testing prior to an acceptable failure rate, the Apollo Earth Landing System (ELS) test program and the Shuttle Solid Rocket Booster Recovery System failure history will be examined, as well as some experiences in the Orion Capsule Parachute Assembly System will be noted.

  19. Rate-weakening friction characterizes both slow sliding and catastrophic failure of landslides

    NASA Astrophysics Data System (ADS)

    Handwerger, Alexander L.; Rempel, Alan W.; Skarbek, Rob M.; Roering, Joshua J.; Hilley, George E.

    2016-09-01

    Catastrophic landslides cause billions of dollars in damages and claim thousands of lives annually, whereas slow-moving landslides with negligible inertia dominate sediment transport on many weathered hillslopes. Surprisingly, both failure modes are displayed by nearby landslides (and individual landslides in different years) subjected to almost identical environmental conditions. Such observations have motivated the search for mechanisms that can cause slow-moving landslides to transition via runaway acceleration to catastrophic failure. A similarly diverse range of sliding behavior, including earthquakes and slow-slip events, occurs along tectonic faults. Our understanding of these phenomena has benefitted from mechanical treatments that rely upon key ingredients that are notably absent from previous landslide descriptions. Here, we describe landslide motion using a rate- and state-dependent frictional model that incorporates a nonlocal stress balance to account for the elastic response to gradients in slip. Our idealized, one-dimensional model reproduces both the displacement patterns observed in slow-moving landslides and the acceleration toward failure exhibited by catastrophic events. Catastrophic failure occurs only when the slip surface is characterized by rate-weakening friction and its lateral dimensions exceed a critical nucleation length h*h* that is shorter for higher effective stresses. However, landslides that are extensive enough to fall within this regime can nevertheless slide slowly for months or years before catastrophic failure. Our results suggest that the diversity of slip behavior observed during landslides can be described with a single model adapted from standard fault mechanics treatments.

  20. Respiratory failure in diabetic ketoacidosis

    PubMed Central

    Konstantinov, Nikifor K; Rohrscheib, Mark; Agaba, Emmanuel I; Dorin, Richard I; Murata, Glen H; Tzamaloukas, Antonios H

    2015-01-01

    Respiratory failure complicating the course of diabetic ketoacidosis (DKA) is a source of increased morbidity and mortality. Detection of respiratory failure in DKA requires focused clinical monitoring, careful interpretation of arterial blood gases, and investigation for conditions that can affect adversely the respiration. Conditions that compromise respiratory function caused by DKA can be detected at presentation but are usually more prevalent during treatment. These conditions include deficits of potassium, magnesium and phosphate and hydrostatic or non-hydrostatic pulmonary edema. Conditions not caused by DKA that can worsen respiratory function under the added stress of DKA include infections of the respiratory system, pre-existing respiratory or neuromuscular disease and miscellaneous other conditions. Prompt recognition and management of the conditions that can lead to respiratory failure in DKA may prevent respiratory failure and improve mortality from DKA. PMID:26240698

  1. CFD research on runaway transient of pumped storage power station caused by pumping power failure

    NASA Astrophysics Data System (ADS)

    Zhang, L. G.; Zhou, D. Q.

    2013-12-01

    To study runaway transient of pumped storage power station caused by pumping power failure, three dimensional unsteady numerical simulations were executed on geometrical model of the whole flow system. Through numerical calculation, the changeable flow configuration and variation law of some parameters such as unit rotate speed,flow rate and static pressure of measurement points were obtained and compared with experimental data. Numerical results show that runaway speed agrees well with experimental date and its error was 3.7%. The unit undergoes pump condition, brake condition, turbine condition and runaway condition with flow characteristic changing violently. In runaway condition, static pressure in passage pulses very strongly which frequency is related to runaway speed.

  2. Serum microRNA expression patterns that predict early treatment failure in prostate cancer patients.

    PubMed

    Singh, Prashant K; Preus, Leah; Hu, Qiang; Yan, Li; Long, Mark D; Morrison, Carl D; Nesline, Mary; Johnson, Candace S; Koochekpour, Shahriar; Kohli, Manish; Liu, Song; Trump, Donald L; Sucheston-Campbell, Lara E; Campbell, Moray J

    2014-02-15

    We aimed to identify microRNA (miRNA) expression patterns in the serum of prostate cancer (CaP) patients that predict the risk of early treatment failure following radical prostatectomy (RP). Microarray and Q-RT-PCR analyses identified 43 miRNAs as differentiating disease stages within 14 prostate cell lines and reflectedpublically available patient data. 34 of these miRNA were detectable in the serum of CaP patients. Association with time to biochemical progression was examined in a cohort of CaP patients following RP. A greater than two-fold increase in hazard of biochemical progression associated with altered expression of miR-103, miR-125b and miR-222 (p<.0008) in the serum of CaP patients. Prediction models based on penalized regression analyses showed that the levels of the miRNAs and PSA together were better at detecting false positives than models without miRNAs, for similar level of sensitivity. Analyses of publically available data revealed significant and reciprocal relationships between changes in CpG methylation and miRNA expression patterns suggesting a role for CpG methylation to regulate miRNA. Exploratory validation supported roles for miR-222 and miR-125b to predict progression risk in CaP. The current study established that expression patterns of serum-detectable miRNAs taken at the time of RP are prognostic for men who are at risk of experiencing subsequent early biochemical progression. These non-invasive approaches could be used to augment treatment decisions.

  3. Ampoule Failure System

    NASA Technical Reports Server (NTRS)

    Watring, Dale A. (Inventor); Johnson, Martin L. (Inventor)

    1996-01-01

    An ampoule failure system for use in material processing furnaces comprising a containment cartridge and an ampoule failure sensor. The containment cartridge contains an ampoule of toxic material therein and is positioned within a furnace for processing. An ampoule failure probe is positioned in the containment cartridge adjacent the ampoule for detecting a potential harmful release of toxic material therefrom during processing. The failure probe is spaced a predetermined distance from the ampoule and is chemically chosen so as to undergo a timely chemical reaction with the toxic material upon the harmful release thereof. The ampoule failure system further comprises a data acquisition system which is positioned externally of the furnace and is electrically connected to the ampoule failure probe so as to form a communicating electrical circuit. The data acquisition system includes an automatic shutdown device for shutting down the furnace upon the harmful release of toxic material. It also includes a resistance measuring device for measuring the resistance of the failure probe during processing. The chemical reaction causes a step increase in resistance of the failure probe whereupon the automatic shutdown device will responsively shut down the furnace.

  4. Catastrophic failures of freezing bags for cellular therapy products: description, cause, and consequences.

    PubMed

    Khuu, H M; Cowley, H; David-Ocampo, V; Carter, C S; Kasten-Sportes, C; Wayne, A S; Solomon, S R; Bishop, M R; Childs, R M; Read, E J

    2002-01-01

    Container integrity is critical for maintaining sterility of cryopreserved cellular therapy products. We investigated a series of catastrophic bag failures, first noticed in early 2001. Process records were reviewed for all PBPC and lymphocyte products cryopreserved in bags from January 2000 through April 2002. Patient charts were also reviewed. One thousand two hundred and four bags were removed from storage for infusion to 261 patients. All products had been cryopreserved in Cryocyte poly(ethylene co-vinyl acetate) (EVA) bags in either 10% DMSO or 5% DMSO and 6% pentastarch. Product volumes were 25-75 mL, and bags were stored with overwrap bags in a liquid nitrogen tank. From January 2000 to April 2001, failure occurred in 10 of 599 (1.7%) bags. From May 2001 to April 2002, 58 of 605 (9.6%) bags failed, typically with extensive fractures that were visible before thaw. Of the 58 that failed, 24 were salvaged by aseptic methods and infused to patients under antibiotic coverage; 10 of those 24 (42%) had positive bacterial cultures. Bag failures were not related to product type, cryoprotectant solution, liquid versus vapor storage, or freezer location. Failures were linked to use of four Cryocyte bag lots manufactured in 2000 and 2001. After replacing these lots with a 1999 Cryocyte lot and with KryoSafe polyfluoroethylene polyfluoropropylene (FEP) bags, no more failures occurred in 75 and 102 bags, respectively, thawed through April 2002. High rates of bag failure were associated with four Cryocyte bag lots. No serious adverse patient effects occurred, but bag failures led to microbial contamination, increased product preparation time, increased antibiotic use, and increased resource expenditure to replace products.

  5. Autoimmune pernicious anaemia as a cause of collapse, heart failure and marked panyctopaenia in a young patient.

    PubMed

    Carey, Justin; Hack, Ebru

    2012-05-08

    A 35-year-old woman with a history of vitiligo, hypothyroidism and amenorrhoea presented with collapse and clinical features of cardiac failure. Laboratory investigations revealed pancytopaenia, the cause of which was found to be vitamin B12 deficiency due to pernicious anaemia. Treatment with intramuscular hydroxycobalamin was commenced and the patient improved steadily with concomitant improvement in her haematological indices. Clinical features of pernicious anaemia which can include marked pancytopaenia, diagnostic approach, associated conditions and approach to treatment are discussed. The importance of surveillance for gastrointestinal malignancy is emphasised.

  6. Autoimmune pernicious anaemia as a cause of collapse, heart failure and marked panyctopaenia in a young patient

    PubMed Central

    Carey, Justin; Hack, Ebru

    2012-01-01

    A 35-year-old woman with a history of vitiligo, hypothyroidism and amenorrhoea presented with collapse and clinical features of cardiac failure. Laboratory investigations revealed pancytopaenia, the cause of which was found to be vitamin B12 deficiency due to pernicious anaemia. Treatment with intramuscular hydroxycobalamin was commenced and the patient improved steadily with concomitant improvement in her haematological indices. Clinical features of pernicious anaemia which can include marked pancytopaenia, diagnostic approach, associated conditions and approach to treatment are discussed. The importance of surveillance for gastrointestinal malignancy is emphasised. PMID:22605831

  7. Anemia and heart failure: a cause of progression or only a consequence?

    PubMed Central

    METRA, MARCO; NODARI, SAVINA; BORDONALI, TANIA; BUGATTI, SILVIA; FONTANELLA, BENEDETTA; LOMBARDI, CARLO; SAPORETTI, ALBERTO; VERZURA, GIULIA; DANESI, ROSSELLA; DEI CAS, LIVIO

    2007-01-01

    Anemia is one of the most frequent co-morbidities in the patients with heart failure. Its prevalence increases from 4–7% in the subjects with asymptomatic left ventricular dysfunction to >30% in the patients with severe heart failure. Renal insufficiency, activation of inflammatory mediators, and treatment with renin-angiotensin antagonists seem to be its main determinants. The results of many studies agree in showing that anemia is a powerful independent determinant of survival in patients with heart failure. However, the mechanisms of this relation are still incompletely understood. Moreover a favourable effect on prognosis of the correction of anemia has not been shown, yet, and also controlled studies assessing its effects on exercise tolerance have yielded controversial results. PMID:21977269

  8. No turning, a mouse mutation causing left-right and axial patterning defects.

    PubMed

    Melloy, P G; Ewart, J L; Cohen, M F; Desmond, M E; Kuehn, M R; Lo, C W

    1998-01-01

    Patterning along the left/right axes helps establish the orientation of visceral organ asymmetries, a process which is of fundamental importance to the viability of an organism. A linkage between left/right and axial patterning is indicated by the finding that a number of genes involved in left/right patterning also play a role in anteroposterior and dorsoventral patterning. We have recovered a spontaneous mouse mutation causing left/right patterning defects together with defects in anteroposterior and dorsoventral patterning. This mutation is recessive lethal and was named no turning (nt) because the mutant embryos fail to undergo embryonic turning. nt embryos exhibit cranial neural tube closure defects and malformed somites and are caudally truncated. Development of the heart arrests at the looped heart tube stage, with cardiovascular defects indicated by ballooning of the pericardial sac and the pooling of blood in various regions of the embryo. Interestingly, in nt embryos, the direction of heart looping was randomized. Nodal and lefty, two genes that are normally expressed only in the left lateral plate mesoderm, show expression in the right and left lateral plate mesoderm. Lefty, which is normally also expressed in the floorplate, is not found in the prospective floor plate of nt embryos. This suggests the possibility of notochordal defects. This was confirmed by histological analysis and the examination of sonic hedgehog, Brachyury, and HNF-3 beta gene expression. These studies showed that the notochord is present in the early nt embryo, but degenerates as development progresses. Overall, these findings support the hypothesis that the notochord plays an active role in left/right patterning. Our results suggest that nt may participate in this process by modulating the notochordal expression of HNF-3 beta.

  9. Heart Failure Questions to Ask Your Doctor

    MedlinePlus

    ... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Heart Failure Questions to Ask Your Doctor Updated:May 9, ... you? This content was last reviewed May 2017. Heart Failure • Home • About Heart FailureCauses and Risks for ...

  10. PARTITIONING RISK AMONG DIFFERENT SOURCES OF NEST FAILURE

    EPA Science Inventory

    Nest predation and nest parasitism receive the most attention as causes of nest failure for North American songbirds. Yet for many populations, interspecific competition, adverse weather, abandonment, nestling starvation, and

    egg failure may also be significant causes of n...

  11. Compounds from multilayer plastic bags cause reproductive failures in artificial insemination.

    PubMed

    Nerin, C; Ubeda, J L; Alfaro, P; Dahmani, Y; Aznar, M; Canellas, E; Ausejo, R

    2014-05-09

    High levels of reproductive failure were detected in some Spanish sow farms in the Spring of 2010. Regular returns to estrus and variable reductions in litter size were observed. The problem started suddenly and did not appear to be related to the quality of the ejaculates, disease, alterations of body condition or any other apparent reasons. Subsequent studies determined that the problem was the origin of the plastic bags used for semen storage. Chemical analysis of the suspicious bags identified unexpected compounds such as BADGE, a cyclic lactone and an unknown phthalate that leached into the semen at concentrations of 0.2 to 2.5 mg/L. Spermatozoa preserved in these bags passed all of the routine quality control tests, and no differences were observed between storage in the control and suspicious bags (p > 0.05). In vitro fecundation tests and endocrine profiler panel analysis (EPP) did not show any alterations, whereas the in vivo tests confirmed the described failure. This is the first described relationship between reproductive failure and toxic compounds released from plastic bags.

  12. Compounds from multilayer plastic bags cause reproductive failures in artificial insemination

    NASA Astrophysics Data System (ADS)

    Nerin, C.; Ubeda, J. L.; Alfaro, P.; Dahmani, Y.; Aznar, M.; Canellas, E.; Ausejo, R.

    2014-05-01

    High levels of reproductive failure were detected in some Spanish sow farms in the Spring of 2010. Regular returns to estrus and variable reductions in litter size were observed. The problem started suddenly and did not appear to be related to the quality of the ejaculates, disease, alterations of body condition or any other apparent reasons. Subsequent studies determined that the problem was the origin of the plastic bags used for semen storage. Chemical analysis of the suspicious bags identified unexpected compounds such as BADGE, a cyclic lactone and an unknown phthalate that leached into the semen at concentrations of 0.2 to 2.5 mg/L. Spermatozoa preserved in these bags passed all of the routine quality control tests, and no differences were observed between storage in the control and suspicious bags (p > 0.05). In vitro fecundation tests and endocrine profiler panel analysis (EPP) did not show any alterations, whereas the in vivo tests confirmed the described failure. This is the first described relationship between reproductive failure and toxic compounds released from plastic bags.

  13. Compounds from multilayer plastic bags cause reproductive failures in artificial insemination

    PubMed Central

    Nerin, C.; Ubeda, J. L.; Alfaro, P.; Dahmani, Y.; Aznar, M.; Canellas, E.; Ausejo, R.

    2014-01-01

    High levels of reproductive failure were detected in some Spanish sow farms in the Spring of 2010. Regular returns to estrus and variable reductions in litter size were observed. The problem started suddenly and did not appear to be related to the quality of the ejaculates, disease, alterations of body condition or any other apparent reasons. Subsequent studies determined that the problem was the origin of the plastic bags used for semen storage. Chemical analysis of the suspicious bags identified unexpected compounds such as BADGE, a cyclic lactone and an unknown phthalate that leached into the semen at concentrations of 0.2 to 2.5 mg/L. Spermatozoa preserved in these bags passed all of the routine quality control tests, and no differences were observed between storage in the control and suspicious bags (p > 0.05). In vitro fecundation tests and endocrine profiler panel analysis (EPP) did not show any alterations, whereas the in vivo tests confirmed the described failure. This is the first described relationship between reproductive failure and toxic compounds released from plastic bags. PMID:24810330

  14. Heart rate turbulence predicts all-cause mortality and sudden death in congestive heart failure patients.

    PubMed

    Cygankiewicz, Iwona; Zareba, Wojciech; Vazquez, Rafael; Vallverdu, Montserrat; Gonzalez-Juanatey, Jose R; Valdes, Mariano; Almendral, Jesus; Cinca, Juan; Caminal, Pere; de Luna, Antoni Bayes

    2008-08-01

    Abnormal heart rate turbulence (HRT) has been documented as a strong predictor of total mortality and sudden death in postinfarction patients, but data in patients with congestive heart failure (CHF) are limited. The aim of this study was to evaluate the prognostic significance of HRT for predicting mortality in CHF patients in New York Heart Association (NYHA) class II-III. In 651 CHF patients with sinus rhythm enrolled into the MUSIC (Muerte Subita en Insuficiencia Cardiaca) study, the standard HRT parameters turbulence onset (TO) and slope (TS), as well as HRT categories, were assessed for predicting total mortality and sudden death. HRT was analyzable in 607 patients, mean age 63 years (434 male), 50% of ischemic etiology. During a median follow up of 44 months, 129 patients died, 52 from sudden death. Abnormal TS and HRT category 2 (HRT2) were independently associated with increased all-cause mortality (HR: 2.10, CI: 1.41 to 3.12, P <.001 and HR: 2.52, CI: 1.56 to 4.05, P <.001; respectively), sudden death (HR: 2.25, CI: 1.13 to 4.46, P = .021 for HRT2), and death due to heart failure progression (HR: 4.11, CI: 1.84 to 9.19, P <.001 for HRT2) after adjustment for clinical covariates in multivariate analysis. The prognostic value of TS for predicting total mortality was similar in various groups dichotomized by age, gender, NYHA class, left ventricular ejection fraction, and CHF etiology. TS was found to be predictive for total mortality only in patients with QRS > 120 ms. HRT is a potent risk predictor for both heart failure and arrhythmic death in patients with class II and III CHF.

  15. 8 CFR 208.10 - Failure to appear at an interview before an asylum officer or failure to follow requirements for...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... asylum officer or failure to follow requirements for fingerprint processing. 208.10 Section 208.10 Aliens... asylum officer or failure to follow requirements for fingerprint processing. Failure to appear for a... right to an interview. Failure to comply with fingerprint processing requirements without good cause may...

  16. 8 CFR 208.10 - Failure to appear at an interview before an asylum officer or failure to follow requirements for...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... asylum officer or failure to follow requirements for fingerprint processing. 208.10 Section 208.10 Aliens... asylum officer or failure to follow requirements for fingerprint processing. Failure to appear for a... right to an interview. Failure to comply with fingerprint processing requirements without good cause may...

  17. 8 CFR 208.10 - Failure to appear at an interview before an asylum officer or failure to follow requirements for...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... asylum officer or failure to follow requirements for fingerprint processing. 208.10 Section 208.10 Aliens... asylum officer or failure to follow requirements for fingerprint processing. Failure to appear for a... right to an interview. Failure to comply with fingerprint processing requirements without good cause may...

  18. 8 CFR 208.10 - Failure to appear at an interview before an asylum officer or failure to follow requirements for...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... asylum officer or failure to follow requirements for fingerprint processing. 208.10 Section 208.10 Aliens... asylum officer or failure to follow requirements for fingerprint processing. Failure to appear for a... right to an interview. Failure to comply with fingerprint processing requirements without good cause may...

  19. 8 CFR 208.10 - Failure to appear at an interview before an asylum officer or failure to follow requirements for...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... asylum officer or failure to follow requirements for fingerprint processing. 208.10 Section 208.10 Aliens... asylum officer or failure to follow requirements for fingerprint processing. Failure to appear for a... right to an interview. Failure to comply with fingerprint processing requirements without good cause may...

  20. Characteristics of Non-Cohesive Embankment Failure

    NASA Astrophysics Data System (ADS)

    Yusof, Z. M.; Wahab, A. K. A.; Ismail, Z.; Amerudin, S.

    2018-04-01

    Embankments are important infrastructure built to provide flood control. They also present risks to property and life due to their potential to fail and cause catastrophic flooding. To mitigate these risks, authorities and regulators need to carefully analyse and inspect dams to identify potential failure modes and protect against them. This paper presents morphology of an embankment study and its sediment behaviour of different grain sizes after the embankment fails. A few experiments were carried out for the embankment size of 1V:3H with different sediment grain sizes; medium and coarser sand. The embankment material used is non-cohesive soil with the embankment height of 0.1 m. The embankment is tested with inflows rate of Q = 0.8 L/s. Experimental results showed the peak discharge for the same inflow rate is affected by the shape of embankment breached. The peak discharge of medium grain size of the embankment is highest, which gave 3.63 L/s in comparison with a coarser embankment. This concludes that the embankment morphology patterns are dissimilar to each other. The flow and dimension of embankment are shown to influence the characteristics of embankment failure.

  1. Temporal Patterns of Oak Mortality in a Southern Appalachian Forest (1991-2006).

    Treesearch

    Cathryn Greenberg; Tara L. Keyser; James Speer

    2011-01-01

    The sustainability of eastern oak-dominated forests is threatened by high oak mortality rates and widespread oak regeneration failure, and presents a challenge to natural area managers. We tracked the rate and cause of mortality of 287 mature oak trees of five species for 15 years to determine the temporal patterns and sources of mortality. We observed a 15.3% total...

  2. Sterilization failures in Singapore: an examination of ligation techniques and failure rates.

    PubMed

    Cheng, M C; Wong, Y M; Rochat, R W; Ratnam, S S

    1977-04-01

    The University Department of Obstetrics and Gynecology, Kandang Kerbau Hospital in Singapore, initiated a study in early 1974 of failure rates for various methods of sterilization and the factors responsible for the failures. During the period January 1974 to March 1976, 51 cases of first pregnancy following ligation were discovered. Cumulative failure rates at 24 months were 0.34 per 100 women for abdominal sterilization, 1.67 for culdoscopic, 3.12 for vaginal, and 4.49 for laparoscopic procedures. Findings for 35 patients who underwent religation showed that recanalization and the establishment of a fistulous opening caused the majority of failures. Clearly, more effective methods of tubal occlusion in sterilization are needed.

  3. 29 CFR 2200.64 - Failure to appear.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 9 2014-07-01 2014-07-01 false Failure to appear. 2200.64 Section 2200.64 Labor... Hearings § 2200.64 Failure to appear. (a) Attendance at hearing. The failure of a party to appear at a... of good cause, may excuse such failure to appear. In such event, the hearing will be rescheduled as...

  4. 29 CFR 2200.64 - Failure to appear.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 9 2012-07-01 2012-07-01 false Failure to appear. 2200.64 Section 2200.64 Labor... Hearings § 2200.64 Failure to appear. (a) Attendance at hearing. The failure of a party to appear at a... of good cause, may excuse such failure to appear. In such event, the hearing will be rescheduled as...

  5. 29 CFR 2200.64 - Failure to appear.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 9 2013-07-01 2013-07-01 false Failure to appear. 2200.64 Section 2200.64 Labor... Hearings § 2200.64 Failure to appear. (a) Attendance at hearing. The failure of a party to appear at a... of good cause, may excuse such failure to appear. In such event, the hearing will be rescheduled as...

  6. 29 CFR 2200.64 - Failure to appear.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 9 2010-07-01 2010-07-01 false Failure to appear. 2200.64 Section 2200.64 Labor... Hearings § 2200.64 Failure to appear. (a) Attendance at hearing. The failure of a party to appear at a... of good cause, may excuse such failure to appear. In such event, the hearing will be rescheduled as...

  7. 29 CFR 2200.64 - Failure to appear.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 9 2011-07-01 2011-07-01 false Failure to appear. 2200.64 Section 2200.64 Labor... Hearings § 2200.64 Failure to appear. (a) Attendance at hearing. The failure of a party to appear at a... of good cause, may excuse such failure to appear. In such event, the hearing will be rescheduled as...

  8. Complex Pattern of Resistance-Associated Substitutions of Hepatitis C Virus after Daclatasvir/Asunaprevir Treatment Failure

    PubMed Central

    Hasebe, Chitomi; Osaki, Yukio; Joko, Kouji; Yagisawa, Hitoshi; Sakita, Shinya; Okushin, Hiroaki; Satou, Takashi; Hisai, Hiroyuki; Abe, Takehiko; Tsuji, Keiji; Tamada, Takashi; Kobashi, Haruhiko; Mitsuda, Akeri; Ide, Yasushi; Ogawa, Chikara; Tsuruta, Syotaro; Takaguchi, Kouichi; Murakawa, Miyako; Asahina, Yasuhiro; Enomoto, Nobuyuki; Izumi, Namiki

    2016-01-01

    Backgrounds & Aims We aimed to clarify the characteristics of resistance-associated substitutions (RASs) after treatment failure with NS5A inhibitor, daclatasvir (DCV) in combination with NS3/4A inhibitor, asunaprevir (ASV), in patients with chronic hepatitis C virus genotype 1b infection. Methods This is a nationwide multicenter study conducted by the Japanese Red Cross Liver Study Group. The sera were obtained from 68 patients with virological failure after 24 weeks of DCV/ASV treatment. RASs in NS5A and NS3 were determined by population sequencing. Results The frequency of signature RASs at position D168 of NS3 was 68%, and at positions L31 and Y93 of NS5A was 79 and 76%, respectively. The frequency of dual signature RASs in NS5A (L31-RAS and Y93-RAS) was 63%. RASs at L28, R30, P32, Q54, P58, and A92 in addition to dual signature RAS were detected in 5, 5, 1, 22, 2, and 0 patients, respectively. In total, triple, quadruple, and quintuple RASs in combination with dual signature RAS were detected in 35, 10, and 1.5% patients, respectively. These RASs were detected in patients without baseline RASs or who prematurely discontinued therapy. Co-existence of D168 RAS in NS3 and L31 and/or Y93 RAS in NS5A was observed in 62% of patients. Conclusion Treatment-emergent RASs after failure with DCV/ASV combination therapy are highly complex in more than 50% of the patients. The identification of complex RAS patterns, which may indicate high levels of resistance to NS5A inhibitors, highlights the need for RAS sequencing when considering re-treatment with regimens including NS5A inhibitors. PMID:27776192

  9. Failure environment analysis tool applications

    NASA Astrophysics Data System (ADS)

    Pack, Ginger L.; Wadsworth, David B.

    1993-02-01

    Understanding risks and avoiding failure are daily concerns for the women and men of NASA. Although NASA's mission propels us to push the limits of technology, and though the risks are considerable, the NASA community has instilled within, the determination to preserve the integrity of the systems upon which our mission and, our employees lives and well-being depend. One of the ways this is being done is by expanding and improving the tools used to perform risk assessment. The Failure Environment Analysis Tool (FEAT) was developed to help engineers and analysts more thoroughly and reliably conduct risk assessment and failure analysis. FEAT accomplishes this by providing answers to questions regarding what might have caused a particular failure; or, conversely, what effect the occurrence of a failure might have on an entire system. Additionally, FEAT can determine what common causes could have resulted in other combinations of failures. FEAT will even help determine the vulnerability of a system to failures, in light of reduced capability. FEAT also is useful in training personnel who must develop an understanding of particular systems. FEAT facilitates training on system behavior, by providing an automated environment in which to conduct 'what-if' evaluation. These types of analyses make FEAT a valuable tool for engineers and operations personnel in the design, analysis, and operation of NASA space systems.

  10. Failure environment analysis tool applications

    NASA Technical Reports Server (NTRS)

    Pack, Ginger L.; Wadsworth, David B.

    1993-01-01

    Understanding risks and avoiding failure are daily concerns for the women and men of NASA. Although NASA's mission propels us to push the limits of technology, and though the risks are considerable, the NASA community has instilled within, the determination to preserve the integrity of the systems upon which our mission and, our employees lives and well-being depend. One of the ways this is being done is by expanding and improving the tools used to perform risk assessment. The Failure Environment Analysis Tool (FEAT) was developed to help engineers and analysts more thoroughly and reliably conduct risk assessment and failure analysis. FEAT accomplishes this by providing answers to questions regarding what might have caused a particular failure; or, conversely, what effect the occurrence of a failure might have on an entire system. Additionally, FEAT can determine what common causes could have resulted in other combinations of failures. FEAT will even help determine the vulnerability of a system to failures, in light of reduced capability. FEAT also is useful in training personnel who must develop an understanding of particular systems. FEAT facilitates training on system behavior, by providing an automated environment in which to conduct 'what-if' evaluation. These types of analyses make FEAT a valuable tool for engineers and operations personnel in the design, analysis, and operation of NASA space systems.

  11. Failure environment analysis tool applications

    NASA Technical Reports Server (NTRS)

    Pack, Ginger L.; Wadsworth, David B.

    1994-01-01

    Understanding risks and avoiding failure are daily concerns for the women and men of NASA. Although NASA's mission propels us to push the limits of technology, and though the risks are considerable, the NASA community has instilled within it, the determination to preserve the integrity of the systems upon which our mission and, our employees lives and well-being depend. One of the ways this is being done is by expanding and improving the tools used to perform risk assessment. The Failure Environment Analysis Tool (FEAT) was developed to help engineers and analysts more thoroughly and reliably conduct risk assessment and failure analysis. FEAT accomplishes this by providing answers to questions regarding what might have caused a particular failure; or, conversely, what effect the occurrence of a failure might have on an entire system. Additionally, FEAT can determine what common causes could have resulted in other combinations of failures. FEAT will even help determine the vulnerability of a system to failures, in light of reduced capability. FEAT also is useful in training personnel who must develop an understanding of particular systems. FEAT facilitates training on system behavior, by providing an automated environment in which to conduct 'what-if' evaluation. These types of analyses make FEAT a valuable tool for engineers and operations personnel in the design, analysis, and operation of NASA space systems.

  12. Epigenome-Wide Association Study Identifies Cardiac Gene Patterning and a Novel Class of Biomarkers for Heart Failure.

    PubMed

    Meder, Benjamin; Haas, Jan; Sedaghat-Hamedani, Farbod; Kayvanpour, Elham; Frese, Karen; Lai, Alan; Nietsch, Rouven; Scheiner, Christina; Mester, Stefan; Bordalo, Diana Martins; Amr, Ali; Dietrich, Carsten; Pils, Dietmar; Siede, Dominik; Hund, Hauke; Bauer, Andrea; Holzer, Daniel Benjamin; Ruhparwar, Arjang; Mueller-Hennessen, Matthias; Weichenhan, Dieter; Plass, Christoph; Weis, Tanja; Backs, Johannes; Wuerstle, Maximilian; Keller, Andreas; Katus, Hugo A; Posch, Andreas E

    2017-10-17

    Biochemical DNA modification resembles a crucial regulatory layer among genetic information, environmental factors, and the transcriptome. To identify epigenetic susceptibility regions and novel biomarkers linked to myocardial dysfunction and heart failure, we performed the first multi-omics study in myocardial tissue and blood of patients with dilated cardiomyopathy and controls. Infinium human methylation 450 was used for high-density epigenome-wide mapping of DNA methylation in left-ventricular biopsies and whole peripheral blood of living probands. RNA deep sequencing was performed on the same samples in parallel. Whole-genome sequencing of all patients allowed exclusion of promiscuous genotype-induced methylation calls. In the screening stage, we detected 59 epigenetic loci that are significantly associated with dilated cardiomyopathy (false discovery corrected P ≤0.05), with 3 of them reaching epigenome-wide significance at P ≤5×10 -8 . Twenty-seven (46%) of these loci could be replicated in independent cohorts, underlining the role of epigenetic regulation of key cardiac transcription regulators. Using a staged multi-omics study design, we link a subset of 517 epigenetic loci with dilated cardiomyopathy and cardiac gene expression. Furthermore, we identified distinct epigenetic methylation patterns that are conserved across tissues, rendering these CpGs novel epigenetic biomarkers for heart failure. The present study provides to our knowledge the first epigenome-wide association study in living patients with heart failure using a multi-omics approach. © 2017 American Heart Association, Inc.

  13. Causes of death in a contemporary adult congenital heart disease cohort.

    PubMed

    Yu, Christopher; Moore, Benjamin M; Kotchetkova, Irina; Cordina, Rachael L; Celermajer, David S

    2018-04-17

    The life expectancy of patients with congenital heart disease (CHD) has significantly improved with advances in their paediatric medical care. Mortality patterns are changing as a result. Our study aims to describe survival and causes of death in a contemporary cohort of adult patients with CHD. We reviewed 3068 patients in our adult CHD database (age ≥16 years, seen at least once in our centre between 2000 and 2015), and documented the number and causes of death, via Australia's National Death Index. Survival and mortality patterns were analysed by complexity of CHD and by underlying congenital diagnosis. Our cohort comprised 3068 adult patients (53% male). The distribution of patients (per the Bethesda classification) was 47% simple, 34% moderate and 18% complex (1% not classifiable). Over a median follow-up of 6.2 years (IQR 3.5-10.4), 341 patients (11%) died with an incidence of 0.4 deaths/100 patient years (py). Survival was significantly worse with increasing complexity of CHD (p<0.001); mortality rate in the simple group was 0.3 deaths/100 py with a median age of death 70 years, and in the complex group was 1.0 death/100 py with a median age of death 34 years. Overall, non-cardiac causes of death outnumbered cardiac causes, at 54% and 46%, respectively. The leading single cause of death was heart failure (17%), followed by malignancy (13%). Simple adult CHD patients mostly died due to non-cardiac causes such as malignancy. Perioperative mortality only accounted for 5% of deaths. Premature death is common in adults with CHD. Although heart failure remains the most common cause of death, in the contemporary era in a specialist CHD centre, non-cardiac related deaths outnumber cardiac deaths, particularly in those with simple CHD lesions. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  14. Temporal Lobe Epilepsy Surgery Failures: A Review

    PubMed Central

    Harroud, Adil; Bouthillier, Alain; Weil, Alexander G.; Nguyen, Dang Khoa

    2012-01-01

    Patients with temporal lobe epilepsy (TLE) are refractory to antiepileptic drugs in about 30% of cases. Surgical treatment has been shown to be beneficial for the selected patients but fails to provide a seizure-free outcome in 20–30% of TLE patients. Several reasons have been identified to explain these surgical failures. This paper will address the five most common causes of TLE surgery failure (a) insufficient resection of epileptogenic mesial temporal structures, (b) relapse on the contralateral mesial temporal lobe, (c) lateral temporal neocortical epilepsy, (d) coexistence of mesial temporal sclerosis and a neocortical lesion (dual pathology); and (e) extratemporal lobe epilepsy mimicking TLE or temporal plus epilepsy. Persistence of epileptogenic mesial structures in the posterior temporal region and failure to distinguish mesial and lateral temporal epilepsy are possible causes of seizure persistence after TLE surgery. In cases of dual pathology, failure to identify a subtle mesial temporal sclerosis or regions of cortical microdysgenesis is a likely explanation for some surgical failures. Extratemporal epilepsy syndromes masquerading as or coexistent with TLE result in incomplete resection of the epileptogenic zone and seizure relapse after surgery. In particular, the insula may be an important cause of surgical failure in patients with TLE. PMID:22934162

  15. Causes of graft failure in simultaneous pancreas-kidney transplantation by various time periods.

    PubMed

    Wakil, Kayo; Sugawara, Yasuhiko; Kokudo, Norihiro; Kadowaki, Takashi

    2013-01-01

    Data collected by the United Network for Organ Sharing from all approved United States transplant programs was analyzed. The data included 26,572 adult diabetic patients who received a primary pancreas transplant between January 1987 and December 2012. Simultaneous pancreas-kidney (SPK) transplantation was the major therapeutic option for diabetes patients. SPK had better graft survival than pancreas transplant alone (PTA) or pancreas-after-kidney (PAK) or pancreas-with-kidney (from a living donor, PWK). The 5-year pancreas graft survival rates for SPK, PWK, PAK, and PTA were 70.0%, 57.2%, 54.0%, and 48.2%, respectively. When long-term SPK pancreas graft survival was examined by various transplant time periods, it was found that survival has remained almost stable since 1996. Graft survival rates were high among the pancreas recipients transplanted in the periods 1996-2000, 2001-2005, and 2006-2012, and the rates were similar: the 5-year rates were 68.9%, 72.4%, and 73.8%, respectively. Technical failure was the leading cause of graft loss during the first year post-transplant, regardless of period: 61.3%, 68.6%, 64.2%, and 71.9% for 1987-1995, 1996-2000, 2001-2005, and 2006-2012, respectively. After one year, chronic rejection was the leading cause of graft loss in all periods: 51.8%, 53.2%, 44.3%, and 40.7% for 1987-1995, 1996-2000, 2001-2005, and 2006-2012, respectively. Chronic rejection accounted for around 50% (or more) of the grafts that survived over five years. Survival of long-term pancreas grafts as well as long-term causes of graft loss remained almost unchanged across the different transplant periods. Clearly, there is a need for a means to identify early markers of chronic rejection, and to control it to improve long-term survival.

  16. Insufficient amount of Cdc2 and continuous activation of Wee1 B are the cause of meiotic failure in porcine growing oocytes.

    PubMed

    Nishimura, Takanori; Shimaoka, Takuma; Kano, Kiyoshi; Naito, Kunihiko

    2009-10-01

    In mammals, growing oocytes with a diameter less than 80% of that of full-grown oocytes cannot start meiotic maturation, and their maturation promoting factor (MPF) cannot be activated by hormonal stimulation or isolation from follicles. The aim of the present study was to identify the key molecules responsible for meiotic failure of these growing oocytes (referred to as "small oocytes" in the present study). To this end, we altered the expression of the molecules involved in MPF activation in the small oocytes of pigs by injecting them with mRNA or antisense RNA (asRNA) and examined the effects on the meiotic ability of the small oocytes. Immunoblotting analyses revealed three defects in small oocytes compared with full-grown oocytes, an inactive mitogen activated protein kinase (MAPK) cascade, a failure of cyclin B synthesis and an insufficient amount of Cdc2. Injection with mRNAs of Mos, the uppermost molecule of the MAPK cascade, cyclin B1, cyclin B2 or Cdc2 into small porcine oocytes indicated directly and for the first time that the cause of meiotic failure of porcine small oocytes is an insufficient amount of Cdc2 rather than MAPK inactivation or failure of cyclin B synthesis. Next, in order to suppress Myt1 and Wee1B, which phosphorylates at inhibitory phosphorylation sites of Cdc2 and inactive MPF, we injected their asRNAs into the porcine small oocytes and found that the Wee1B asRNA significantly increased meiotic ability, whereas the Myt1 asRNA had no effect. When Cdc2 overexpression and suppression of Wee1B expression were simultaneously induced in the small oocytes of pigs, about 70% of the small oocytes resumed meiosis, and this rate was nearly comparable with that of the full-grown oocytes. These results strongly suggest that an insufficient amount of Cdc2 and continuous activation of Wee1 B are the cause of meiotic failure of small oocytes in pigs.

  17. Acute allograft failure in thoracic organ transplantation.

    PubMed

    Jahania, M S; Mullett, T W; Sanchez, J A; Narayan, P; Lasley, R D; Mentzer, R M

    2000-01-01

    Thoracic organ transplantation is an effective form of treatment for end-stage heart and lung disease. Despite major advances in the field, transplant patients remain at risk for acute allograft dysfunction, a major cause of early and late mortality. The most common causes of allograft failure include primary graft failure secondary to inadequate heart and lung preservation during cold storage, cellular rejection, and various donor-recipient-related factors. During cold storage and early reperfusion, heart and lung allografts are vulnerable to intracellular calcium overload, acidosis, cell swelling, injury mediated by reactive oxygen species, and the inflammatory response. Brain death itself is associated with a reduction in myocardial contractility, and recipient-related factors such as preexisting pulmonary hypertension can lead to acute right heart failure and the pulmonary reimplantation response. The development of new methods to prevent or treat these various causes of acute graft failure could lead to a marked improvement in short- and long-term survival of patients undergoing thoracic organ transplantation.

  18. Failure in generating hemopoietic stem cells is the primary cause of death from cytomegalovirus disease in the immunocompromised host

    SciTech Connect

    Mutter, W.; Reddehase, M.J.; Busch, F.W.

    1988-05-01

    We have shown in a murine model system for cytomegalovirus (CMV) disease in the immunocompromised host that CMV infection interferes with the earliest detectable step in hemopoiesis, the generation of the stem cell CFU-S-I, and thereby prevents the autoreconstitution of bone marrow after sublethal irradiation. The antihemopoietic effect could not be ascribed to a direct infection of stem cells. The failure in hemopoiesis was prevented by adoptive transfer of antiviral CD8+ T lymphocytes and could be overcome by syngeneic bone marrow transplantation. CD8+ T lymphocytes and bone marrow cells both mediated survival, although only CD8+ T lymphocytes were able tomore » limit virus multiplication in host tissues. We concluded that not the cytopathic effect of virus replication in host tissues, but the failure in hemopoiesis, is the primary cause of death in murine CMV disease.« less

  19. Primary failure of eruption: further characterization of a rare eruption disorder.

    PubMed

    Frazier-Bowers, Sylvia A; Koehler, Karen E; Ackerman, James L; Proffit, William R

    2007-05-01

    Posterior open bite has several possible causes, including primary failure of eruption (PFE) that affects all teeth distal to the most mesial involved tooth, mechanical failure of eruption (MFE) (primarily ankylosis) that affects only the involved tooth or teeth, and soft-tissue interferences with eruption (other). Radiographs and other clinical records for 97 cases of failure of posterior eruption submitted for consultation were analyzed to further characterize PFE and distinguish it from MFE. Of the 97 cases, 38 were judged to be clear-cut PFE; 19 were diagnosed as MFE; 32 were classified as indeterminate failure because they were too young to be certain of the distinction between PFE and MFE; and 8 were placed in the "other" category. Two subtypes of PFE were observed. In type 1, eruption failure occurred at or near the same time for all teeth in an affected quadrant. In type 2, a gradient of the time of failure was present, so that some further development of the teeth posterior to the most mesial affected tooth was observed before eruption failure. A family history of eruption problems was noted in 10 of the 38 PFE subjects (26%), and a pedigree analysis was done for 4 families. This was consistent with autosomal dominant transmission. The distinction between PFE and MFE is clinically important because it determines whether all posterior teeth, or only individual affected teeth, will not respond to orthodontic force. Certain diagnosis often requires progress radiographs so that the pattern of eruption of teeth distal to the most mesial affected tooth can be observed.

  20. Hyperthyroidism as a reversible cause of right ventricular overload and congestive heart failure

    PubMed Central

    Di Giovambattista, Raniero

    2008-01-01

    We describe a case of severe congestive heart failure and right ventricular overload associated with overt hyperthyroidism, completely reversed with antithyroid therapy in a few week. It represents a very unusual presentation of overt hyperthyroidism because of the severity of right heart failure. The impressive right ventricular volume overload made mandatory to perform transesophageal echo and angio-TC examination to exclude the coexistence of ASD or anomalous pulmonary venous return. Only a few cases of reversible right heart failure, with or without pulmonary hypertension, have been reported worldwide. In our case the most striking feature has been the normalization of the cardiovascular findings after six weeks of tiamazole therapy. PMID:18549503

  1. Differing ERP patterns caused by suction and puff stimuli.

    PubMed

    Choi, Mi-Hyun; Kim, Hyung-Sik; Baek, Ji-Hye; Lee, Jung-Chul; Park, Sung-Jun; Jeong, Ul-Ho; Gim, Seon-Young; You, Ji Hye; Kim, Sung-Pil; Lim, Dae-Woon; Kim, Hyun-Jun; Chung, Soon-Cheol

    2015-05-06

    The present study compared event-related potential (ERP) patterns for two stimuli types, puff and suction, by applying these stimuli to the fingers; ERP patterns for the two stimuli were compared at C3, an area related to somatosensory perception, and at FC5, an area related to motor function. Participants were 12 healthy males in their 20s (mean age=23.1±2.0 years). One session consisted of a Control Phase (3s), a Stimulation Phase (3s), and a Rest Phase (9s). During the Stimulation Phase, a 4-psi suction or puff stimulus was applied to the first joint of the right index finger. After completion of the session, a subjective magnitude test was presented. In all phases, electroencephalography signals were recorded. We extracted maximum positive amplitude and minimum negative amplitude as well as relevant latency values for C3 and FC5 signals. Suction and puff stimuli had similar subjective magnitude scores. For both C3 and FC5, the maximum and minimum amplitude latency was reached earlier for the suction stimulus than for the puff stimulus. In conclusion, when suction and puff stimuli of the same intensity were applied to the fingers, the suction stimulus caused a more sensitive response in the somatosensory area (C3) and motor area (FC5) than did the puff stimulus. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. Snow fracture: From micro-cracking to global failure

    NASA Astrophysics Data System (ADS)

    Capelli, Achille; Reiweger, Ingrid; Schweizer, Jürg

    2017-04-01

    Slab avalanches are caused by a crack forming and propagating in a weak layer within the snow cover, which eventually causes the detachment of the overlying cohesive slab. The gradual damage process leading to the nucleation of the initial failure is still not entirely understood. Therefore, we studied the damage process preceding snow failure by analyzing the acoustic emissions (AE) generated by bond failure or micro-cracking. The AE allow studying the ongoing progressive failure in a non-destructive way. We performed fully load-controlled failure experiments on snow samples presenting a weak layer and recorded the generated AE. The size and frequency of the generated AE increased before failure revealing an acceleration of the damage process with increased size and frequency of damage and/or microscopic cracks. The AE energy was power-law distributed and the exponent (b-value) decreased approaching failure. The waiting time followed an exponential distribution with increasing exponential coefficient λ before failure. The decrease of the b-value and the increase of λ correspond to a change in the event distribution statistics indicating a transition from homogeneously distributed uncorrelated damage producing mostly small AE to localized damage, which cause larger correlated events which leads to brittle failure. We observed brittle failure for the fast experiment and a more ductile behavior for the slow experiments. This rate dependence was reflected also in the AE signature. In the slow experiments the b value and λ were almost constant, and the energy rate increase was moderate indicating that the damage process was in a stable state - suggesting the damage and healing processes to be balanced. On a shorter time scale, however, the AE parameters varied indicating that the damage process was not steady but consisted of a sum of small bursts. We assume that the bursts may have been generated by cascades of correlated micro-cracks caused by localization of

  3. [Acetaminophen (paracetamol) causing renal failure: report on 3 pediatric cases].

    PubMed

    Le Vaillant, J; Pellerin, L; Brouard, J; Eckart, P

    2013-06-01

    Renal failure secondary to acetaminophen poisoning is rare and occurs in approximately 1-2 % of patients with acetaminophen overdose. The pathophysiology is still being debated, and renal acetaminophen toxicity consists of acute tubular necrosis, without complication if treated promptly. Renal involvement can sometimes occur without prior liver disease, and early renal manifestations usually occur between the 2nd and 7th day after the acute acetaminophen poisoning. While therapy is exclusively symptomatic, sometimes serious metabolic complications can be observed. The monitoring of renal function should therefore be considered as an integral part of the management of children with acute, severe acetaminophen intoxication. We report 3 cases of adolescents who presented with acute renal failure as a result of voluntary drug intoxication with acetaminophen. One of these 3 girls developed severe renal injury without elevated hepatic transaminases. None of the 3 girls' renal function required hemodialysis, but one of the 3 patients had metabolic complications after her acetaminophen poisoning. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  4. Failure analysis of a tool steel torque shaft

    NASA Technical Reports Server (NTRS)

    Reagan, J. R.

    1981-01-01

    A low design load drive shaft used to deliver power from an experimental exhaust heat recovery system to the crankshaft of an experimental diesel truck engine failed during highway testing. An independent testing laboratory analyzed the failure by routine metallography and attributed the failure to fatigue induced by a banded microstructure. Visual examination by NASA of the failed shaft plus the knowledge of the torsional load that it carried pointed to a 100 percent ductile failure with no evidence of fatigue. Scanning electron microscopy confirmed this. Torsional test specimens were produced from pieces of the failed shaft and torsional overload testing produced identical failures to that which had occurred in the truck engine. This pointed to a failure caused by a high overload and although the microstructure was defective it was not the cause of the failure.

  5. Mutations in genes encoding condensin complex proteins cause microcephaly through decatenation failure at mitosis

    PubMed Central

    Martin, Carol-Anne; Murray, Jennie E.; Carroll, Paula; Leitch, Andrea; Mackenzie, Karen J.; Halachev, Mihail; Fetit, Ahmed E.; Keith, Charlotte; Bicknell, Louise S.; Fluteau, Adeline; Gautier, Philippe; Hall, Emma A.; Joss, Shelagh; Soares, Gabriela; Silva, João; Bober, Michael B.; Duker, Angela; Wise, Carol A.; Quigley, Alan J.; Phadke, Shubha R.; Wood, Andrew J.; Vagnarelli, Paola; Jackson, Andrew P.

    2016-01-01

    Compaction of chromosomes is essential for accurate segregation of the genome during mitosis. In vertebrates, two condensin complexes ensure timely chromosome condensation, sister chromatid disentanglement, and maintenance of mitotic chromosome structure. Here, we report that biallelic mutations in NCAPD2, NCAPH, or NCAPD3, encoding subunits of these complexes, cause microcephaly. In addition, hypomorphic Ncaph2 mice have significantly reduced brain size, with frequent anaphase chromatin bridge formation observed in apical neural progenitors during neurogenesis. Such DNA bridges also arise in condensin-deficient patient cells, where they are the consequence of failed sister chromatid disentanglement during chromosome compaction. This results in chromosome segregation errors, leading to micronucleus formation and increased aneuploidy in daughter cells. These findings establish “condensinopathies” as microcephalic disorders, with decatenation failure as an additional disease mechanism for microcephaly, implicating mitotic chromosome condensation as a key process ensuring mammalian cerebral cortex size. PMID:27737959

  6. Are Icelandic rock-slope failures paraglacial? Age evaluation of seventeen rock-slope failures in the Skagafjörður area, based on geomorphological stacking, radiocarbon dating and tephrochronology

    NASA Astrophysics Data System (ADS)

    Mercier, Denis; Coquin, Julien; Feuillet, Thierry; Decaulne, Armelle; Cossart, Etienne; Jónsson, Helgi Pall; Sæmundsson, Þorstein

    2017-11-01

    In Iceland there are numerous rock-slope failures, especially in the Tertiary basaltic formations of the northern, eastern and northwestern regions. The temporal pattern of rock-slope failures is fundamental for understanding post-glacial events. In the Skagafjörður district, central northern Iceland, 17 rock-slope failures were investigated to determine the age of their occurrence. A geomorphic survey was carried out to identify and characterize landform units, both on the rock-slope failures and in their immediate vicinity. In this coastal area, we used geomorphological stacking which included the relationship between rock-slope failures and raised beaches caused by glacial isostatic rebounds, the chronology of which was established in previous studies. We searched for depressions on the rock-slope failures to then excavate a series of pits and map the stratigraphy. The resulting stratigraphic framework was then validated using (i) radiocarbon dating of wood remains, and (ii) tephrochronology, both of which were complemented by age-depth model calibration. The results confirm that all the rock-slope failures potentially occurred before the Boreal (8 ka), while 94% occurred before the Preboreal (10 ka). They all potentially occurred after the glacial retreat following the maximal ice extent and the Preboreal. More precisely, 11 of them potentially occurred between the Preboreal and the first half of the Holocene. This study demonstrates the relationship between the deglaciation and destabilization of slopes during the paraglacial phase (debuttressing, decompression, glacial isostatic rebound, seismic activity, etc.), which are also controlling factors favouring landsliding, but are difficult to identify for each individual rock-slope failure.

  7. Spatial and temporal patterns of bank failure during extreme flood events: Evidence of nonlinearity and self-organised criticality at the basin scale?

    NASA Astrophysics Data System (ADS)

    Thompson, C. J.; Croke, J. C.; Grove, J. R.

    2012-04-01

    Non-linearity in physical systems provides a conceptual framework to explain complex patterns and form that are derived from complex internal dynamics rather than external forcings, and can be used to inform modeling and improve landscape management. One process that has been investigated previously to explore the existence of self-organised critical system (SOC) in river systems at the basin-scale is bank failure. Spatial trends in bank failure have been previously quantified to determine if the distribution of bank failures at the basin scale exhibit the necessary power law magnitude/frequency distributions. More commonly bank failures are investigated at a small-scale using several cross-sections with strong emphasis on local-scale factors such as bank height, cohesion and hydraulic properties. Advancing our understanding of non-linearity in such processes, however, requires many more studies where both the spatial and temporal measurements of the process can be used to investigate the existence or otherwise of non-linearity and self-organised criticality. This study presents measurements of bank failure throughout the Lockyer catchment in southeast Queensland, Australia, which experienced an extreme flood event in January 2011 resulting in the loss of human lives and geomorphic channel change. The most dominant form of fluvial adjustment consisted of changes in channel geometry and notably widespread bank failures, which were readily identifiable as 'scalloped' shaped failure scarps. The spatial extents of these were mapped using high-resolution LiDAR derived digital elevation model and were verified by field surveys and air photos. Pre-flood event LiDAR coverage for the catchment also existed allowing direct comparison of the magnitude and frequency of bank failures from both pre and post-flood time periods. Data were collected and analysed within a GIS framework and investigated for power-law relationships. Bank failures appeared random and occurred

  8. 36 CFR 223.137 - Causes for debarment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., fire prevention, and the disposal of slash; (2) Protection of soil, water, wildlife, range, cultural, and timber resources and protection of improvements when such failure causes significant environmental, resource, or improvements damage; (3) Removal of designated timber when such failure causes substantial...

  9. Failure of Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Samitier, Gonzalo; Marcano, Alejandro I.; Alentorn-Geli, Eduard; Cugat, Ramon; Farmer, Kevin W; Moser, Michael W

    2015-01-01

    The present review classifies and describes the multifactorial causes of anterior cruciate ligament (ACL) surgery failure, concentrating on preventing and resolving such situations. The article particularly focuses on those causes that require ACL revision due to recurrent instability, without neglecting those that affect function or produce persistent pain. Although primary ACL reconstruction has satisfactory outcome rates as high as 97%, it is important to identify the causes of failure, because satisfactory outcomes in revision surgery can drop to as much as 76%. It is often possible to identify a primary or secondary cause of ACL surgery failure; even the most meticulous planning can give rise to unexpected findings during the intervention. The adopted protocol should therefore be sufficiently flexible to adapt to the course of surgery. Preoperative patient counseling is essential. The surgeon should limit the patient’s expectations for the outcome by explaining the complexity of this kind of procedure. With adequate preoperative planning, close attention to details and realistic patient expectations, ACL revision surgery may offer beneficial and satisfactory results for the patient. PMID:26550585

  10. Acute liver failure caused by 'fat burners' and dietary supplements: a case report and literature review.

    PubMed

    Yellapu, Radha K; Mittal, Vivek; Grewal, Priya; Fiel, Mariaisabel; Schiano, Thomas

    2011-03-01

    Globally, people are struggling with obesity. Many effective, nonconventional methods of weight reduction, such as herbal and natural dietary supplements, are increasingly being sought. Fat burners are believed to raise metabolism, burn more calories and hasten fat loss. Despite patient perceptions that herbal remedies are free of adverse effects, some supplements are associated with severe hepatotoxicity. The present report describes a young healthy woman who presented with fulminant hepatic failure requiring emergent liver transplantation caused by a dietary supplement and fat burner containing usnic acid, green tea and guggul tree extracts. Thorough investigation, including histopathological examination, revealed no other cause of hepatotoxicity. The present case adds to the increasing number of reports of hepatotoxicity associated with dietary supplements containing usnic acid, and highlights that herbal extracts from green tea or guggul tree may not be free of adverse effects. Until these products are more closely regulated and their advertising better scrutinized, physicians and patients should become more familiar with herbal products that are commonly used as weight loss supplements and recognize those that are potentially harmful.

  11. ATM CMG bearing failure analysis

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The cause or causes for the failure of ATM CMG S/N 5 (Skylab 1) and the anomalies associated with ATM CMG S/N 6 (Skylab 2) were investigated. Skylab telemetry data were reviewed and presented in the form of parameter distributions. The theory that the problems were caused by marginal bearing lubrication was studied along with the effects of orbital conditions on lubricants. Bearing tests were performed to investigate the effect of lubricant or lack of lubricant in the ATM CMG bearings and the dispersion and migration of the lubricant. The vacuum and weightless conditions of space were simulated in the bearing tests. Analysis of the results of the tests conducted points to inadequate lubrication as the predominant factor causing the failure of ATM CMG S/N 5 (Skylab 1) and the anomalies associated with ATM CMG S/N 6 (Skylab 2).

  12. Analysis of Emergency Diesel Generators Failure Incidents in Nuclear Power Plants

    NASA Astrophysics Data System (ADS)

    Hunt, Ronderio LaDavis

    In early years of operation, emergency diesel generators have had a minimal rate of demand failures. Emergency diesel generators are designed to operate as a backup when the main source of electricity has been disrupted. As of late, EDGs (emergency diesel generators) have been failing at NPPs (nuclear power plants) around the United States causing either station blackouts or loss of onsite and offsite power. These failures occurred from a specific type called demand failures. This thesis evaluated the current problem that raised concern in the nuclear industry which was averaging 1 EDG demand failure/year in 1997 to having an excessive event of 4 EDG demand failure year which occurred in 2011. To determine the next occurrence of the extreme event and possible cause to an event of such happening, two analyses were conducted, the statistical and root cause analysis. Considering the statistical analysis in which an extreme event probability approach was applied to determine the next occurrence year of an excessive event as well as, the probability of that excessive event occurring. Using the root cause analysis in which the potential causes of the excessive event occurred by evaluating, the EDG manufacturers, aging, policy changes/ maintenance practices and failure components. The root cause analysis investigated the correlation between demand failure data and historical data. Final results from the statistical analysis showed expectations of an excessive event occurring in a fixed range of probability and a wider range of probability from the extreme event probability approach. The root-cause analysis of the demand failure data followed historical statistics for the EDG manufacturer, aging and policy changes/ maintenance practices but, indicated a possible cause regarding the excessive event with the failure components. Conclusions showed the next excessive demand failure year, prediction of the probability and the next occurrence year of such failures, with an

  13. Numerical Simulation and Experimental Validation of Failure Caused by Vibration of a Fan

    NASA Astrophysics Data System (ADS)

    Zhou, Qiang; Han, Wu; Feng, Jianmei; Jia, Xiaohan; Peng, Xueyuan

    2017-08-01

    This paper presents the root cause analysis of an unexpected fracture occurred on the blades of a motor fan used in a natural gas reciprocating compressor unit. A finite element model was established to investigate the natural frequencies and modal shapes of the fan, and a modal test was performed to verify the numerical results. It was indicated that the numerical results agreed well with experimental data. The third order natural frequency was close to the six times excitation frequency, and the corresponding modal shape was the combination of bending and torsional vibration, which consequently contributed to low-order resonance and fracture failure of the fan. The torsional moment obtained by a torsional vibration analysis of the compressor shaft system was exerted on the numerical model of the fan to evaluate the dynamic stress response of the fan. The results showed that the stress concentration regions on the numerical model were consistent with the location of fractures on the fan. Based on the numerical simulation and experimental validation, some recommendations were given to improve the reliability of the motor fan.

  14. Lungs in Heart Failure

    PubMed Central

    Apostolo, Anna; Giusti, Giuliano; Gargiulo, Paola; Bussotti, Maurizio; Agostoni, Piergiuseppe

    2012-01-01

    Lung function abnormalities both at rest and during exercise are frequently observed in patients with chronic heart failure, also in the absence of respiratory disease. Alterations of respiratory mechanics and of gas exchange capacity are strictly related to heart failure. Severe heart failure patients often show a restrictive respiratory pattern, secondary to heart enlargement and increased lung fluids, and impairment of alveolar-capillary gas diffusion, mainly due to an increased resistance to molecular diffusion across the alveolar capillary membrane. Reduced gas diffusion contributes to exercise intolerance and to a worse prognosis. Cardiopulmonary exercise test is considered the “gold standard” when studying the cardiovascular, pulmonary, and metabolic adaptations to exercise in cardiac patients. During exercise, hyperventilation and consequent reduction of ventilation efficiency are often observed in heart failure patients, resulting in an increased slope of ventilation/carbon dioxide (VE/VCO2) relationship. Ventilatory efficiency is as strong prognostic and an important stratification marker. This paper describes the pulmonary abnormalities at rest and during exercise in the patients with heart failure, highlighting the principal diagnostic tools for evaluation of lungs function, the possible pharmacological interventions, and the parameters that could be useful in prognostic assessment of heart failure patients. PMID:23365739

  15. Biological mechanisms of premature ovarian failure caused by psychological stress based on support vector regression

    PubMed Central

    Wang, Xiu-Feng; Zhang, Lei; Wu, Qing-Hua; Min, Jian-Xin; Ma, Na; Luo, Lai-Cheng

    2015-01-01

    Psychological stress has become a common and important cause of premature ovarian failure (POF). Therefore, it is very important to explore the mechanisms of POF resulting from psychological stress. Sixty SD rats were randomly divided into control and model groups. Biomolecules associated with POF (β-EP, IL-1, NOS, NO, GnRH, CRH, FSH, LH, E2, P, ACTH, and CORT) were measured in the control and psychologically stressed rats. The regulation relationships of the biomolecules were explored in the psychologically stressed state using support vector regression (SVR). The values of β-EP, IL-1, NOS, and GnRH in the hypothalamus decreased significantly, and the value of NO changed slightly, when the values of 3 biomolecules in the hypothalamic-pituitary-adrenal axis decreased. The values of E2 and P in the hypothalamic-pituitary-ovarian axis decreased significantly, while the values of FSH and LH changed slightly, when the values of the biomolecules in the hypothalamus decreased. The values of FSH and LH in the pituitary layer of the hypothalamic-pituitary-ovarian axis changed slightly when the values of E2 and P in the target gland layer of the hypothalamic-pituitary-ovarian axis decreased. An Imbalance in the neuroendocrine-immune bimolecular network, particularly the failure of the feedback action of the target gland layer to pituitary layer in the pituitary-ovarian axis, is possibly one of the pathogenic mechanisms of POF. PMID:26885082

  16. [Perioperative acute kidney injury and failure].

    PubMed

    Chhor, Vibol; Journois, Didier

    2014-04-01

    Perioperative period is very likely to lead to acute renal failure because of anesthesia (general or perimedullary) and/or surgery which can cause acute kidney injury. Characterization of acute renal failure is based on serum creatinine level which is imprecise during and following surgery. Studies are based on various definitions of acute renal failure with different thresholds which skewed their comparisons. The RIFLE classification (risk, injury, failure, loss, end stage kidney disease) allows clinicians to distinguish in a similar manner between different stages of acute kidney injury rather than using a unique definition of acute renal failure. Acute renal failure during the perioperative period can mainly be explained by iatrogenic, hemodynamic or surgical causes and can result in an increased morbi-mortality. Prevention of this complication requires hemodynamic optimization (venous return, cardiac output, vascular resistance), discontinuation of nephrotoxic drugs but also knowledge of the different steps of the surgery to avoid further degradation of renal perfusion. Diuretics do not prevent acute renal failure and may even push it forward especially during the perioperative period when venous retourn is already reduced. Edema or weight gain following surgery are not correlated with the vascular compartment volume, much less with renal perfusion. Treatment of perioperative acute renal failure is similar to other acute renal failure. Renal replacement therapy must be mastered to prevent any additional risk of hemodynamic instability or hydro-electrolytic imbalance. Copyright © 2014 Association Société de néphrologie. Published by Elsevier SAS. All rights reserved.

  17. Fatigue failure of metal components as a factor in civil aircraft accidents

    NASA Technical Reports Server (NTRS)

    Holshouser, W. L.; Mayner, R. D.

    1972-01-01

    A review of records maintained by the National Transportation Safety Board showed that 16,054 civil aviation accidents occurred in the United States during the 3-year period ending December 31, 1969. Material failure was an important factor in the cause of 942 of these accidents. Fatigue was identified as the mode of the material failures associated with the cause of 155 accidents and in many other accidents the records indicated that fatigue failures might have been involved. There were 27 fatal accidents and 157 fatalities in accidents in which fatigue failures of metal components were definitely identified. Fatigue failures associated with accidents occurred most frequently in landing-gear components, followed in order by powerplant, propeller, and structural components in fixed-wing aircraft and tail-rotor and main-rotor components in rotorcraft. In a study of 230 laboratory reports on failed components associated with the cause of accidents, fatigue was identified as the mode of failure in more than 60 percent of the failed components. The most frequently identified cause of fatigue, as well as most other types of material failures, was improper maintenance (including inadequate inspection). Fabrication defects, design deficiencies, defective material, and abnormal service damage also caused many fatigue failures. Four case histories of major accidents are included in the paper as illustrations of some of the factors invovled in fatigue failures of aircraft components.

  18. Mutations in genes encoding condensin complex proteins cause microcephaly through decatenation failure at mitosis.

    PubMed

    Martin, Carol-Anne; Murray, Jennie E; Carroll, Paula; Leitch, Andrea; Mackenzie, Karen J; Halachev, Mihail; Fetit, Ahmed E; Keith, Charlotte; Bicknell, Louise S; Fluteau, Adeline; Gautier, Philippe; Hall, Emma A; Joss, Shelagh; Soares, Gabriela; Silva, João; Bober, Michael B; Duker, Angela; Wise, Carol A; Quigley, Alan J; Phadke, Shubha R; Wood, Andrew J; Vagnarelli, Paola; Jackson, Andrew P

    2016-10-01

    Compaction of chromosomes is essential for accurate segregation of the genome during mitosis. In vertebrates, two condensin complexes ensure timely chromosome condensation, sister chromatid disentanglement, and maintenance of mitotic chromosome structure. Here, we report that biallelic mutations in NCAPD2, NCAPH, or NCAPD3, encoding subunits of these complexes, cause microcephaly. In addition, hypomorphic Ncaph2 mice have significantly reduced brain size, with frequent anaphase chromatin bridge formation observed in apical neural progenitors during neurogenesis. Such DNA bridges also arise in condensin-deficient patient cells, where they are the consequence of failed sister chromatid disentanglement during chromosome compaction. This results in chromosome segregation errors, leading to micronucleus formation and increased aneuploidy in daughter cells. These findings establish "condensinopathies" as microcephalic disorders, with decatenation failure as an additional disease mechanism for microcephaly, implicating mitotic chromosome condensation as a key process ensuring mammalian cerebral cortex size. © 2016 Martin et al.; Published by Cold Spring Harbor Laboratory Press.

  19. Hyaluronidase 2 Deficiency Causes Increased Mesenchymal Cells, Congenital Heart Defects, and Heart Failure.

    PubMed

    Chowdhury, Biswajit; Xiang, Bo; Liu, Michelle; Hemming, Richard; Dolinsky, Vernon W; Triggs-Raine, Barbara

    2017-01-01

    Hyaluronan (HA) is required for endothelial-to-mesenchymal transition and normal heart development in the mouse. Heart abnormalities in hyaluronidase 2 (HYAL2)-deficient ( Hyal2 - /- ) mice and humans suggested removal of HA is also important for normal heart development. We have performed longitudinal studies of heart structure and function in Hyal2 -/- mice to determine when, and how, HYAL2 deficiency leads to these abnormalities. Echocardiography revealed atrial enlargement, atrial tissue masses, and valvular thickening at 4 weeks of age, as well as diastolic dysfunction that progressed with age, in Hyal2 -/- mice. These abnormalities were associated with increased HA, vimentin-positive cells, and fibrosis in Hyal2 -/- compared with control mice. Based on the severity of heart dysfunction, acute and chronic groups of Hyal2 -/- mice that died at an average of 12 and 25 weeks respectively, were defined. Increased HA levels and mesenchymal cells, but not vascular endothelial growth factor in Hyal2 -/- embryonic hearts, suggest that HYAL2 is important to inhibit endothelial-to-mesenchymal transition. Consistent with this, in wild-type embryos, HYAL2 and HA were readily detected, and HA levels decreased with age. These data demonstrate that disruption of normal HA catabolism in Hyal2 -/- mice causes increased HA, which may promote endothelial-to-mesenchymal transition and proliferation of mesenchymal cells. Excess endothelial-to-mesenchymal transition, resulting in increased mesenchymal cells, is the likely cause of morphological heart abnormalities in both humans and mice. In mice, these abnormalities result in progressive and severe diastolic dysfunction, culminating in heart failure. © 2016 The Authors.

  20. Failure Atlas for Rolling Bearings in Wind Turbines

    SciTech Connect

    Tallian, T. E.

    2006-01-01

    This Atlas is structured as a supplement to the book: T.E. Tallian: Failure Atlas for Hertz Contact Machine Elements, 2nd edition, ASME Press New York, (1999). The content of the atlas comprises plate pages from the book that contain bearing failure images, application data, and descriptions of failure mode, image, and suspected failure causes. Rolling bearings are a critical component of the mainshaft system, gearbox and generator in the rapidly developing technology of power generating wind turbines. The demands for long service life are stringent; the design load, speed and temperature regimes are demanding and the environmental conditions including weather,more » contamination, impediments to monitoring and maintenance are often unfavorable. As a result, experience has shown that the rolling bearings are prone to a variety of failure modes that may prevent achievement of design lives. Morphological failure diagnosis is extensively used in the failure analysis and improvement of bearing operation. Accumulated experience shows that the failure appearance and mode of failure causation in wind turbine bearings has many distinguishing features. The present Atlas is a first effort to collect an interpreted database of specifically wind turbine related rolling bearing failures and make it widely available. This Atlas is structured as a supplement to the book: T. E. Tallian: Failure Atlas for Hertz Contact Machine Elements, 2d edition, ASME Press New York, (1999). The main body of that book is a comprehensive collection of self-contained pages called Plates, containing failure images, bearing and application data, and three descriptions: failure mode, image and suspected failure causes. The Plates are sorted by main failure mode into chapters. Each chapter is preceded by a general technical discussion of the failure mode, its appearance and causes. The Plates part is supplemented by an introductory part, describing the appearance classification and failure

  1. Temporal-varying failures of nodes in networks

    NASA Astrophysics Data System (ADS)

    Knight, Georgie; Cristadoro, Giampaolo; Altmann, Eduardo G.

    2015-08-01

    We consider networks in which random walkers are removed because of the failure of specific nodes. We interpret the rate of loss as a measure of the importance of nodes, a notion we denote as failure centrality. We show that the degree of the node is not sufficient to determine this measure and that, in a first approximation, the shortest loops through the node have to be taken into account. We propose approximations of the failure centrality which are valid for temporal-varying failures, and we dwell on the possibility of externally changing the relative importance of nodes in a given network by exploiting the interference between the loops of a node and the cycles of the temporal pattern of failures. In the limit of long failure cycles we show analytically that the escape in a node is larger than the one estimated from a stochastic failure with the same failure probability. We test our general formalism in two real-world networks (air-transportation and e-mail users) and show how communities lead to deviations from predictions for failures in hubs.

  2. Exome sequencing identifies titin mutations causing hereditary myopathy with early respiratory failure (HMERF) in families of diverse ethnic origins.

    PubMed

    Toro, Camilo; Olivé, Montse; Dalakas, Marinos C; Sivakumar, Kumaraswami; Bilbao, Juan M; Tyndel, Felix; Vidal, Noemí; Farrero, Eva; Sambuughin, Nyamkhishig; Goldfarb, Lev G

    2013-03-20

    Hereditary myopathy with early respiratory failure (HMERF) was described in several North European families and recently linked to a titin gene (TTN) mutation. We independently studied HMERF-like diseases with the purpose to identify the cause, refine diagnostic criteria, and estimate the frequency of this disease among myopathy patients of various ethnic origins. Whole exome sequencing analysis was carried out in a large U.S. family that included seven members suffering from skeletal muscle weakness and respiratory failure. Subsequent mutation screening was performed in further 45 unrelated probands with similar phenotypes. Studies included muscle strength evaluation, nerve conduction studies and concentric needle EMG, respiratory function test, cardiologic examination, and muscle biopsy. A novel TTN p.Gly30150Asp mutation was identified in the highly conserved A-band of titin that co-segregated with the disease in the U.S. family. Screening of 45 probands initially diagnosed as myofibrillar myopathy (MFM) but excluded based on molecular screening for the known MFM genes led to the identification of a previously reported TTN p.Cys30071Arg mutation in one patient. This same mutation was also identified in a patient with suspected HMERF. The p.Gly30150Asp and p.Cys30071Arg mutations are localized to a side chain of fibronectin type III element A150 of the 10th C-zone super-repeat of titin. Missense mutations in TTN are the cause of HMERF in families of diverse origins. A comparison of phenotypic features of HMERF caused by the three known TTN mutations in various populations allowed to emphasize distinct clinical/pathological features that can serve as the basis for diagnosis. The newly identified p.Gly30150Asp and the p.Cys30071Arg mutation are localized to a side chain of fibronectin type III element A150 of the 10th C-zone super-repeat of titin.

  3. BEEHAVE: a systems model of honeybee colony dynamics and foraging to explore multifactorial causes of colony failure

    PubMed Central

    Becher, Matthias A; Grimm, Volker; Thorbek, Pernille; Horn, Juliane; Kennedy, Peter J; Osborne, Juliet L

    2014-01-01

    A notable increase in failure of managed European honeybee Apis mellifera L. colonies has been reported in various regions in recent years. Although the underlying causes remain unclear, it is likely that a combination of stressors act together, particularly varroa mites and other pathogens, forage availability and potentially pesticides. It is experimentally challenging to address causality at the colony scale when multiple factors interact. In silico experiments offer a fast and cost-effective way to begin to address these challenges and inform experiments. However, none of the published bee models combine colony dynamics with foraging patterns and varroa dynamics. We have developed a honeybee model, BEEHAVE, which integrates colony dynamics, population dynamics of the varroa mite, epidemiology of varroa-transmitted viruses and allows foragers in an agent-based foraging model to collect food from a representation of a spatially explicit landscape. We describe the model, which is freely available online (www.beehave-model.net). Extensive sensitivity analyses and tests illustrate the model's robustness and realism. Simulation experiments with various combinations of stressors demonstrate, in simplified landscape settings, the model's potential: predicting colony dynamics and potential losses with and without varroa mites under different foraging conditions and under pesticide application. We also show how mitigation measures can be tested. Synthesis and applications. BEEHAVE offers a valuable tool for researchers to design and focus field experiments, for regulators to explore the relative importance of stressors to devise management and policy advice and for beekeepers to understand and predict varroa dynamics and effects of management interventions. We expect that scientists and stakeholders will find a variety of applications for BEEHAVE, stimulating further model development and the possible inclusion of other stressors of potential importance to honeybee

  4. BEEHAVE: a systems model of honeybee colony dynamics and foraging to explore multifactorial causes of colony failure.

    PubMed

    Becher, Matthias A; Grimm, Volker; Thorbek, Pernille; Horn, Juliane; Kennedy, Peter J; Osborne, Juliet L

    2014-04-01

    A notable increase in failure of managed European honeybee Apis mellifera L. colonies has been reported in various regions in recent years. Although the underlying causes remain unclear, it is likely that a combination of stressors act together, particularly varroa mites and other pathogens, forage availability and potentially pesticides. It is experimentally challenging to address causality at the colony scale when multiple factors interact. In silico experiments offer a fast and cost-effective way to begin to address these challenges and inform experiments. However, none of the published bee models combine colony dynamics with foraging patterns and varroa dynamics.We have developed a honeybee model, BEEHAVE, which integrates colony dynamics, population dynamics of the varroa mite, epidemiology of varroa-transmitted viruses and allows foragers in an agent-based foraging model to collect food from a representation of a spatially explicit landscape.We describe the model, which is freely available online (www.beehave-model.net). Extensive sensitivity analyses and tests illustrate the model's robustness and realism. Simulation experiments with various combinations of stressors demonstrate, in simplified landscape settings, the model's potential: predicting colony dynamics and potential losses with and without varroa mites under different foraging conditions and under pesticide application. We also show how mitigation measures can be tested. Synthesis and applications . BEEHAVE offers a valuable tool for researchers to design and focus field experiments, for regulators to explore the relative importance of stressors to devise management and policy advice and for beekeepers to understand and predict varroa dynamics and effects of management interventions. We expect that scientists and stakeholders will find a variety of applications for BEEHAVE, stimulating further model development and the possible inclusion of other stressors of potential importance to honeybee colony

  5. Incidence and predictors of 6 months mortality after an acute heart failure event in rural Uganda: The Mbarara Heart Failure Registry (MAHFER).

    PubMed

    Abeya, Fardous Charles; Lumori, Boniface Amanee Elias; Akello, Suzan Joan; Annex, Brian H; Buda, Andrew J; Okello, Samson

    2018-03-29

    We sought to estimate the incidence and predictors of all-cause mortality 6 months after heart failure hospitalization in Uganda. Mbarara Heart Failure Registry is a cohort of patients hospitalized with a clinical diagnosis of heart failure at Mbarara Regional Referral Hospital, Uganda. We measured serum electrolytes, cardiac markers, and echocardiograms. All participants were followed until death or end of 6 months. We used Fine and Gray models to estimate the incidence and predictors all-cause mortality. A total of 215 participants were enrolled, 141 (66%) were women, and mean age 53 (standard deviation 22) years. Nineteen (9%) had diabetes, 40 (19%) had HIV, and 119 (55%) had hypertension. The overall incidence of all-cause mortality was 3.58 (95% CI 2.92, 4.38) per 1000 person-days. Men had higher incidence of death compared to women (4.02 vs 3.37 per 1000 person-days). The incidence of all-cause mortality during hospitalization was almost twice that of in the community (27.5 vs 14.77 per 1000 person-days). In adjusted analysis, increasing age, NYHA class IV, decreasing renal function, smoking, each unit increase in serum levels of Potassium, BNP, and Creatine kinase-MB predicted increased incidence of 6 months all-cause death whereas taking beta-blockers and having an index admission on a weekend compared to a week day predicted survival. There is a high incidence of all-cause mortality occurring in-hospital among patients hospitalized with heart failure in rural Uganda. Heart failure directed therapies should be instituted to curb heart failure-related mortality. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Examining the causes of memory strength variability: Recollection, attention failure, or encoding variability?

    PubMed Central

    Koen, Joshua D.; Aly, Mariam; Wang, Wei-Chun; Yonelinas, Andrew P.

    2013-01-01

    A prominent finding in recognition memory is that studied items are associated with more variability in memory strength than new items. Here, we test three competing theories for why this occurs - the encoding variability, attention failure, and recollection accounts. Distinguishing amongst these theories is critical because each provides a fundamentally different account of the processes underlying recognition memory. The encoding variability and attention failure accounts propose that old item variance will be unaffected by retrieval manipulations because the processes producing this effect are ascribed to encoding. The recollection account predicts that both encoding and retrieval manipulations that preferentially affect recollection will affect memory variability. These contrasting predictions were tested by examining the effect of response speeding (Experiment 1), dividing attention at retrieval (Experiment 2), context reinstatement (Experiment 3), and increased test delay (Experiment 4) on recognition performance. The results of all four experiments confirmed the predictions of the recollection account, and were inconsistent with the encoding variability account. The evidence supporting the attention failure account was mixed, with two of the four experiments confirming the account and two disconfirming the account. These results indicate that encoding variability and attention failure are insufficient accounts of memory variance, and provide support for the recollection account. Several alternative theoretical accounts of the results are also considered. PMID:23834057

  7. Causes of chronic orthostatic hypotension

    NASA Technical Reports Server (NTRS)

    Robertson, D.; Robertson, R. M.

    1994-01-01

    OBJECTIVE: To determine the frequency of various causes of orthostatic hypotension. DESIGN: Survey. SETTING: Tertiary referral center. PATIENTS: One hundred patients with moderate to severe orthostatic hypotension. RESULTS: Twenty-seven percent of the patients had primary autonomic failure, 35% had secondary autonomic failure, and 38% had hypotension without evidence of generalized autonomic degeneration. CONCLUSIONS: In a tertiary referral center, only a minority of patients with severe orthostatic hypotension will have Shy-Drager syndrome or Bradbury-Eggleston syndrome as their primary disease. Occasional patients who initially appear to have Bradbury-Eggleston syndrome ultimately prove to have Shy-Drager syndrome or paraneoplastic autonomic failure. Antidepressant drugs, even in low doses, remain a major overlooked cause of orthostatic hypotension.

  8. Stress Analysis and Testing at the Marshall Space Flight Center to Study Cause and Corrective Action of Space Shuttle External Tank Stringer Failures

    NASA Technical Reports Server (NTRS)

    Wingate, Robert J.

    2012-01-01

    After the launch scrub of Space Shuttle mission STS-133 on November 5, 2010, large cracks were discovered in two of the External Tank intertank stringers. The NASA Marshall Space Flight Center, as managing center for the External Tank Project, coordinated the ensuing failure investigation and repair activities with several organizations, including the manufacturer, Lockheed Martin. To support the investigation, the Marshall Space Flight Center formed an ad-hoc stress analysis team to complement the efforts of Lockheed Martin. The team undertook six major efforts to analyze or test the structural behavior of the stringers. Extensive finite element modeling was performed to characterize the local stresses in the stringers near the region of failure. Data from a full-scale tanking test and from several subcomponent static load tests were used to confirm the analytical conclusions. The analysis and test activities of the team are summarized. The root cause of the stringer failures and the flight readiness rationale for the repairs that were implemented are discussed.

  9. A multi-sensor approach to landslide monitoring of rainfall-induced failures in Scotland.

    NASA Astrophysics Data System (ADS)

    Gilles, Charlie; Hoey, Trevor; Williams, Richard

    2017-04-01

    Landslides are of significant interest in upland areas of the United Kingdom due to their: complex mechanics, potential to channelize into hazardous debris flows and their costly potential impacts on infrastructure. The British Geological Survey National Landslide Database contains an average of 367 landslides per year (from 1970). Slope failures in the UK are typically triggered by extended periods of intense rainfall, and can occur at any time of year. In any given rainfall event that triggers landslides, most potentially vulnerable slopes remain stable. Accurate warning systems would be facilitated by identifying landslide precursors prior to failure events. This project tests whether such precursors can be identified in the valley of Glen Ogle, Scotland (87 km north-west of Edinburgh), where in summer 2004 two debris flows blocked the main road (A85), trapping fifty-seven people. Two adjacent sites have been selected on a west facing slope in Glen Ogle, one of which (the control) has been stable since at least 2004 and the other failed in 2004 and remains unstable. Understanding the immediate causes and antecedent conditions responsible for landslides requires a multi-scale approach. This project uses multiple sensors to assess failure mechanisms of landslides in Glen Ogle: (1) 3-monthly, high (1.8 arcsec) resolution terrestrial laser scanning of topography to detect changes and identify patterns of movement prior to major failure, using the Riegl VZ-1000 (NERC Geophysical Equipment Fund); (2) rainfall and soil moisture data to monitor pore pressure of landslide failure prior to and after hydrologically triggered events; (3) monitoring ground motion using grain-scale sensors which are becoming lower cost, more efficient in terms of power, and can be wirelessly networked these will be used to detect small scale movement of the landslide. Comparative data from the control and test sites will be presented, from which patterns of surface deformation between failure

  10. Investigation of Possible Wellbore Cement Failures During Hydraulic Fracturing Operations

    SciTech Connect

    Kim, Jihoon; Moridis, George

    2014-11-01

    We model and assess the possibility of shear failure, using the Mohr-Coulomb model ? along the vertical well by employing a rigorous coupled flow-geomechanic analysis. To this end, we vary the values of cohesion between the well casing and the surrounding cement to representing different quality levels of the cementing operation (low cohesion corresponds to low-quality cement and/or incomplete cementing). The simulation results show that there is very little fracturing when the cement is of high quality.. Conversely, incomplete cementing and/or weak cement can causes significant shear failure and the evolution of long fractures/cracks along the vertical well. Specifically, lowmore » cohesion between the well and cemented areas can cause significant shear failure along the well, but the same cohesion as the cemented zone does not cause shear failure. When the hydraulic fracturing pressure is high, low cohesion of the cement can causes fast propagation of shear failure and of the resulting fracture/crack, but a high-quality cement with no weak zones exhibits limited shear failure that is concentrated near the bottom of the vertical part of the well. Thus, high-quality cement and complete cementing along the vertical well appears to be the strongest protection against shear failure of the wellbore cement and, consequently, against contamination hazards to drinking water aquifers during hydraulic fracturing operations.« less

  11. Causes, Patterns, and Severity of Androgen Excess in 1205 Consecutively Recruited Women.

    PubMed

    Elhassan, Yasir S; Idkowiak, Jan; Smith, Karen; Asia, Miriam; Gleeson, Helena; Webster, Rachel; Arlt, Wiebke; O'Reilly, Michael W

    2018-03-01

    Androgen excess in women is predominantly due to underlying polycystic ovary syndrome (PCOS). However, there is a lack of clarity regarding patterns and severity of androgen excess that should be considered predictive of non-PCOS pathology. We examined the diagnostic utility of simultaneous measurement of serum dehydroepiandrosterone sulfate (DHEAS), androstenedione (A4), and testosterone (T) to delineate biochemical signatures and cutoffs predictive of non-PCOS disorders in women with androgen excess. Retrospective review of all women undergoing serum androgen measurement at a large tertiary referral center between 2012 and 2016. Serum A4 and T were measured by tandem mass spectrometry and DHEAS by immunoassay. Patients with at least one increased serum androgen underwent phenotyping by clinical notes review. In 1205 women, DHEAS, A4, and T were measured simultaneously. PCOS was the most common diagnosis in premenopausal (89%) and postmenopausal women (29%). A4 was increased in all adrenocortical carcinoma (ACC) cases (n = 15) and T in all ovarian hyperthecosis (OHT) cases (n = 7); all but one case of congenital adrenal hyperplasia (CAH; n = 18) were identified by increased levels of A4 and/or T. In premenopausal women, CAH was a prevalent cause of severe A4 (59%) and T (43%) excess; severe DHEAS excess was predominantly due to PCOS (80%). In postmenopausal women, all cases of severe DHEAS and A4 excess were caused by ACC and severe T excess equally by ACC and OHT. Pattern and severity of androgen excess are important predictors of non-PCOS pathology and may be used to guide further investigations as appropriate.

  12. Control of large commercial vehicle accidents caused by front tire failures.

    DOT National Transportation Integrated Search

    1975-08-01

    The Federal Highway Administration of the u.s. Department of Transportation is concerned with the loss of life, injury, and property damage that result from front tire failure on heavyduty trucks. The Bureau of Motor Carrier Safety contracted with Ul...

  13. The Spectrum of Renal Allograft Failure

    PubMed Central

    Chand, Sourabh; Atkinson, David; Collins, Clare; Briggs, David; Ball, Simon; Sharif, Adnan; Skordilis, Kassiani; Vydianath, Bindu; Neil, Desley; Borrows, Richard

    2016-01-01

    Background Causes of “true” late kidney allograft failure remain unclear as study selection bias and limited follow-up risk incomplete representation of the spectrum. Methods We evaluated all unselected graft failures from 2008–2014 (n = 171; 0–36 years post-transplantation) by contemporary classification of indication biopsies “proximate” to failure, DSA assessment, clinical and biochemical data. Results The spectrum of graft failure changed markedly depending on the timing of allograft failure. Failures within the first year were most commonly attributed to technical failure, acute rejection (with T-cell mediated rejection [TCMR] dominating antibody-mediated rejection [ABMR]). Failures beyond a year were increasingly dominated by ABMR and ‘interstitial fibrosis with tubular atrophy’ without rejection, infection or recurrent disease (“IFTA”). Cases of IFTA associated with inflammation in non-scarred areas (compared with no inflammation or inflammation solely within scarred regions) were more commonly associated with episodes of prior rejection, late rejection and nonadherence, pointing to an alloimmune aetiology. Nonadherence and late rejection were common in ABMR and TCMR, particularly Acute Active ABMR. Acute Active ABMR and nonadherence were associated with younger age, faster functional decline, and less hyalinosis on biopsy. Chronic and Chronic Active ABMR were more commonly associated with Class II DSA. C1q-binding DSA, detected in 33% of ABMR episodes, were associated with shorter time to graft failure. Most non-biopsied patients were DSA-negative (16/21; 76.1%). Finally, twelve losses to recurrent disease were seen (16%). Conclusion This data from an unselected population identifies IFTA alongside ABMR as a very important cause of true late graft failure, with nonadherence-associated TCMR as a phenomenon in some patients. It highlights clinical and immunological characteristics of ABMR subgroups, and should inform clinical practice and

  14. Myxoedema coma: an almost forgotten, yet still existing cause of multiorgan failure

    PubMed Central

    Salomo, Louise Havkrog; Laursen, Adam Hoegsbro; Reiter, Nanna; Feldt-Rasmussen, Ulla

    2014-01-01

    A 48-year-old man was admitted to department of emergency medicine at a tertiary referral hospital due to dizziness and fatigue. Clinical features on admission were non-pitting oedema, dry skin, very sparse hair, a hoarse voice, hypothermia (rectal temperature 28.7°C), macroglossia, sinus bradycardia and slow cerebration. Blood tests revealed severe hypothyroidism. During admission, the patient developed respiratory failure, renal failure, bleeding symptoms and diffuse colitis. The patient was treated with hydrocortisone and levothyroxine and he survived miraculously. This case describes a patient with myxoedema coma with severe hypothermia and cardiac involvement with development of multiorgan dysfunction all linked to the severe depletion of triiodothyronine. PMID:24481020

  15. Myxoedema coma: an almost forgotten, yet still existing cause of multiorgan failure.

    PubMed

    Salomo, Louise Havkrog; Laursen, Adam Hoegsbro; Reiter, Nanna; Feldt-Rasmussen, Ulla

    2014-01-30

    A 48-year-old man was admitted to department of emergency medicine at a tertiary referral hospital due to dizziness and fatigue. Clinical features on admission were non-pitting oedema, dry skin, very sparse hair, a hoarse voice, hypothermia (rectal temperature 28.7°C), macroglossia, sinus bradycardia and slow cerebration. Blood tests revealed severe hypothyroidism. During admission, the patient developed respiratory failure, renal failure, bleeding symptoms and diffuse colitis. The patient was treated with hydrocortisone and levothyroxine and he survived miraculously. This case describes a patient with myxoedema coma with severe hypothermia and cardiac involvement with development of multiorgan dysfunction all linked to the severe depletion of triiodothyronine.

  16. 32-Bit-Wide Memory Tolerates Failures

    NASA Technical Reports Server (NTRS)

    Buskirk, Glenn A.

    1990-01-01

    Electronic memory system of 32-bit words corrects bit errors caused by some common type of failures - even failure of entire 4-bit-wide random-access-memory (RAM) chip. Detects failure of two such chips, so user warned that ouput of memory may contain errors. Includes eight 4-bit-wide DRAM's configured so each bit of each DRAM assigned to different one of four parallel 8-bit words. Each DRAM contributes only 1 bit to each 8-bit word.

  17. Field failure mechanisms for photovoltaic modules

    NASA Technical Reports Server (NTRS)

    Dumas, L. N.; Shumka, A.

    1981-01-01

    Beginning in 1976, Department of Energy field centers have installed and monitored a number of field tests and application experiments using current state-of-the-art photovoltaic modules. On-site observations of module physical and electrical degradation, together with in-depth laboratory analysis of failed modules, permits an overall assessment of the nature and causes of early field failures. Data on failure rates are presented, and key failure mechanisms are analyzed with respect to origin, effect, and prospects for correction. It is concluded that all failure modes identified to date are avoidable or controllable through sound design and production practices.

  18. Improved detection of congestive heart failure via probabilistic symbolic pattern recognition and heart rate variability metrics.

    PubMed

    Mahajan, Ruhi; Viangteeravat, Teeradache; Akbilgic, Oguz

    2017-12-01

    A timely diagnosis of congestive heart failure (CHF) is crucial to evade a life-threatening event. This paper presents a novel probabilistic symbol pattern recognition (PSPR) approach to detect CHF in subjects from their cardiac interbeat (R-R) intervals. PSPR discretizes each continuous R-R interval time series by mapping them onto an eight-symbol alphabet and then models the pattern transition behavior in the symbolic representation of the series. The PSPR-based analysis of the discretized series from 107 subjects (69 normal and 38 CHF subjects) yielded discernible features to distinguish normal subjects and subjects with CHF. In addition to PSPR features, we also extracted features using the time-domain heart rate variability measures such as average and standard deviation of R-R intervals. An ensemble of bagged decision trees was used to classify two groups resulting in a five-fold cross-validation accuracy, specificity, and sensitivity of 98.1%, 100%, and 94.7%, respectively. However, a 20% holdout validation yielded an accuracy, specificity, and sensitivity of 99.5%, 100%, and 98.57%, respectively. Results from this study suggest that features obtained with the combination of PSPR and long-term heart rate variability measures can be used in developing automated CHF diagnosis tools. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Good Models Gone Bad: Quantifying and Predicting Parameter-Induced Climate Model Simulation Failures

    NASA Astrophysics Data System (ADS)

    Lucas, D. D.; Klein, R.; Tannahill, J.; Brandon, S.; Covey, C. C.; Domyancic, D.; Ivanova, D. P.

    2012-12-01

    Simulations using IPCC-class climate models are subject to fail or crash for a variety of reasons. Statistical analysis of the failures can yield useful insights to better understand and improve the models. During the course of uncertainty quantification (UQ) ensemble simulations to assess the effects of ocean model parameter uncertainties on climate simulations, we experienced a series of simulation failures of the Parallel Ocean Program (POP2). About 8.5% of our POP2 runs failed for numerical reasons at certain combinations of parameter values. We apply support vector machine (SVM) classification from the fields of pattern recognition and machine learning to quantify and predict the probability of failure as a function of the values of 18 POP2 parameters. The SVM classifiers readily predict POP2 failures in an independent validation ensemble, and are subsequently used to determine the causes of the failures via a global sensitivity analysis. Four parameters related to ocean mixing and viscosity are identified as the major sources of POP2 failures. Our method can be used to improve the robustness of complex scientific models to parameter perturbations and to better steer UQ ensembles. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 and was funded by the Uncertainty Quantification Strategic Initiative Laboratory Directed Research and Development Project at LLNL under project tracking code 10-SI-013 (UCRL LLNL-ABS-569112).

  20. Slope failures in municipal solid waste dumps and landfills: a review.

    PubMed

    Blight, Geoffrey

    2008-10-01

    Between 1977 and 2005 six large-scale failures of municipal solid waste dumps and landfills have been recorded in the technical literature. The volumes of waste mobilized in the failures varied from 10-12 000 m(3) in a failure that killed nearly 300 people to 1.5 million m(3) in a failure that caused no deaths or injuries. Of the six failures, four occurred in dumps that, as far as is known, had not been subjected to any prior technical investigation of their shear stability. The remaining two failures occurred in engineer-designed landfills, one of which practised leachate recirculation, and the other co-disposed of liquid waste along with solid waste. The paper reviews, describes and analyses the failures and summarizes their causes.

  1. Carcinoma of the ampulla of Vater: patterns of failure following resection and benefit of chemoradiotherapy.

    PubMed

    Palta, Manisha; Patel, Pretesh; Broadwater, Gloria; Willett, Christopher; Pepek, Joseph; Tyler, Douglas; Zafar, S Yousuf; Uronis, Hope; Hurwitz, Herbert; White, Rebekah; Czito, Brian

    2012-05-01

    Ampullary carcinoma is a rare malignancy. Despite radical resection, survival rates remain low with high rates of local failure. We performed a single-institution outcomes analysis to define the role of concurrent chemoradiotherapy (CRT) in addition to surgery. A retrospective analysis was performed of all patients undergoing potentially curative pancreaticoduodenectomy for adenocarcinoma of the ampulla of Vater at Duke University Hospitals between 1976 and 2009. Time-to-event analysis was performed comparing all patients who underwent surgery alone to the cohort of patients receiving CRT in addition to surgery. Local control (LC), disease-free survival (DFS), overall survival (OS), and metastases-free survival (MFS) were estimated using the Kaplan-Meier method. A total of 137 patients with ampullary carcinoma underwent Whipple procedure. Of these, 61 patients undergoing resection received adjuvant (n = 43) or neoadjuvant (n = 18) CRT. Patients receiving chemoradiotherapy were more likely to have poorly differentiated tumors (P = .03). Of 18 patients receiving neoadjuvant therapy, 67% were downstaged on final pathology with 28% achieving pathologic complete response (pCR). With a median follow-up of 8.8 years, 3-year local control was improved in patients receiving CRT (88% vs 55%, P = .001) with trend toward 3-year DFS (66% vs 48%, P = .09) and OS (62% vs 46%, P = .074) benefit in patients receiving CRT. Long-term survival rates are low and local failure rates high following radical resection alone. Given patterns of relapse with surgery alone and local control benefit in patients receiving CRT, the use of chemoradiotherapy in selected patients should be considered.

  2. Acute liver failure caused by ‘fat burners’ and dietary supplements: A case report and literature review

    PubMed Central

    Radha Krishna, Y; Mittal, V; Grewal, P; Fiel, MI; Schiano, T

    2011-01-01

    Globally, people are struggling with obesity. Many effective, non-conventional methods of weight reduction, such as herbal and natural dietary supplements, are increasingly being sought. Fat burners are believed to raise metabolism, burn more calories and hasten fat loss. Despite patient perceptions that herbal remedies are free of adverse effects, some supplements are associated with severe hepatotoxicity. The present report describes a young healthy woman who presented with fulminant hepatic failure requiring emergent liver transplantation caused by a dietary supplement and fat burner containing usnic acid, green tea and guggul tree extracts. Thorough investigation, including histopathological examination, revealed no other cause of hepatotoxicity. The present case adds to the increasing number of reports of hepatotoxicity associated with dietary supplements containing usnic acid, and highlights that herbal extracts from green tea or guggul tree may not be free of adverse effects. Until these products are more closely regulated and their advertising better scrutinized, physicians and patients should become more familiar with herbal products that are commonly used as weight loss supplements and recognize those that are potentially harmful. PMID:21499580

  3. Examining the causes of memory strength variability: recollection, attention failure, or encoding variability?

    PubMed

    Koen, Joshua D; Aly, Mariam; Wang, Wei-Chun; Yonelinas, Andrew P

    2013-11-01

    A prominent finding in recognition memory is that studied items are associated with more variability in memory strength than new items. Here, we test 3 competing theories for why this occurs-the encoding variability, attention failure, and recollection accounts. Distinguishing among these theories is critical because each provides a fundamentally different account of the processes underlying recognition memory. The encoding variability and attention failure accounts propose that old item variance will be unaffected by retrieval manipulations because the processes producing this effect are ascribed to encoding. The recollection account predicts that both encoding and retrieval manipulations that preferentially affect recollection will affect memory variability. These contrasting predictions were tested by examining the effect of response speeding (Experiment 1), dividing attention at retrieval (Experiment 2), context reinstatement (Experiment 3), and increased test delay (Experiment 4) on recognition performance. The results of all 4 experiments confirm the predictions of the recollection account and are inconsistent with the encoding variability account. The evidence supporting the attention failure account is mixed, with 2 of the 4 experiments confirming the account and 2 disconfirming the account. These results indicate that encoding variability and attention failure are insufficient accounts of memory variance and provide support for the recollection account. Several alternative theoretical accounts of the results are also considered. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  4. Mechanisms, predictors, and trends of electrical failure of Riata leads.

    PubMed

    Cheung, Jim W; Al-Kazaz, Mohamed; Thomas, George; Liu, Christopher F; Ip, James E; Bender, Seth R; Siddiqi, Faisal K; Markowitz, Steven M; Lerman, Bruce B

    2013-10-01

    Riata and Riata ST implantable cardioverter-defibrillator leads have been shown to be prone to structural and electrical failure. To determine predictors, mechanisms, and temporal patterns of Riata/ST lead electrical failure. All 314 patients who underwent Riata/ST lead implantation at our institution with greater than or equal to 90 days of follow-up were studied. The Kaplan-Meier analysis of lead survival was performed. Results from the returned product analysis of explanted leads with electrical lead failure were recorded. During a median follow-up of 4.1 years, the Riata lead electrical failure rate was 6.6%. The rate of externalized conductors among failed leads was 57%. The engineering analysis of 10 explanted leads revealed 5 (50%) leads with electrical failure owing to breach of ethylene tetrafluoroethylene conductor coating. Female gender (hazard ratio 2.7; 95% confidence interval 1.1-6.7; P = .04) and age (hazard ratio 0.95; 95% confidence interval 0.92-0.97; P < .001) were multivariate predictors of lead failure. By using log-log analysis, we noted that the rate of Riata lead failure initially increased exponentially with a power of 2.1 but leads surviving past 4 years had a linear pattern of lead failure with a power of 1.0. Younger age and female gender are independent predictors of Riata lead failure. Loss of integrity of conductor cables with ethylene tetrafluoroethylene coating is an important mode of electrical failure of the Riata lead. Further study of Riata lead failure trends is warranted to guide lead management. © 2013 Heart Rhythm Society. All rights reserved.

  5. Critical fault patterns determination in fault-tolerant computer systems

    NASA Technical Reports Server (NTRS)

    Mccluskey, E. J.; Losq, J.

    1978-01-01

    The method proposed tries to enumerate all the critical fault-patterns (successive occurrences of failures) without analyzing every single possible fault. The conditions for the system to be operating in a given mode can be expressed in terms of the static states. Thus, one can find all the system states that correspond to a given critical mode of operation. The next step consists in analyzing the fault-detection mechanisms, the diagnosis algorithm and the process of switch control. From them, one can find all the possible system configurations that can result from a failure occurrence. Thus, one can list all the characteristics, with respect to detection, diagnosis, and switch control, that failures must have to constitute critical fault-patterns. Such an enumeration of the critical fault-patterns can be directly used to evaluate the overall system tolerance to failures. Present research is focused on how to efficiently make use of these system-level characteristics to enumerate all the failures that verify these characteristics.

  6. Local Failure After Episcleral Brachytherapy for Posterior Uveal Melanoma: Patterns, Risk Factors, and Management.

    PubMed

    Bellerive, Claudine; Aziz, Hassan A; Bena, James; Wilkinson, Allan; Suh, John H; Plesec, Thomas; Singh, Arun D

    2017-05-01

    To evaluate the patterns, the risk factors, and the management of recurrence following brachytherapy in patients with posterior uveal melanoma, given that an understanding of the recurrence patterns can improve early recognition and management of local treatment failure in such patients. Retrospective cohort study. Setting: Multispecialty tertiary care center. A total of 375 eyes treated with episcleral brachytherapy for posterior uveal melanoma from January 2004 to December 2014. Exclusion criteria included inadequate follow-up (<1 year) and previous radiation therapy. Main Outcomes and Measures: Local control rate and time to recurrence were the primary endpoints. Kaplan-Meier estimation and Cox proportional hazards models were conducted to identify risk factors for recurrence. Twenty-one patients (5.6%) experienced recurrence (follow-up range 12-156 months; median 47 months). The median time to recurrence was 18 months (range 4-156 months). Five-year estimated local recurrence rate was 6.6%. The majority (90.5%) of the recurrences occurred within the first 5 years. The predominant site of recurrence was at the tumor margin (12 patients, 57.1%). Univariate analysis identified 3 statistically significant recurrence risk factors: advanced age, largest basal diameter, and the use of adjuvant transpupillary thermotherapy (TTT). Recurrent tumors were managed by repeat brachytherapy, TTT, or enucleation. Local recurrences following brachytherapy are uncommon 5 years after episcleral brachytherapy. Follow-up intervals can be adjusted to reflect time to recurrence. Most of the eyes with recurrent tumor can be salvaged by conservative methods. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. 3-Dimensional Root Cause Diagnosis via Co-analysis

    SciTech Connect

    Zheng, Ziming; Lan, Zhiling; Yu, Li

    2012-01-01

    With the growth of system size and complexity, reliability has become a major concern for large-scale systems. Upon the occurrence of failure, system administrators typically trace the events in Reliability, Availability, and Serviceability (RAS) logs for root cause diagnosis. However, RAS log only contains limited diagnosis information. Moreover, the manual processing is time-consuming, error-prone, and not scalable. To address the problem, in this paper we present an automated root cause diagnosis mechanism for large-scale HPC systems. Our mechanism examines multiple logs to provide a 3-D fine-grained root cause analysis. Here, 3-D means that our analysis will pinpoint the failure layer,more » the time, and the location of the event that causes the problem. We evaluate our mechanism by means of real logs collected from a production IBM Blue Gene/P system at Oak Ridge National Laboratory. It successfully identifies failure layer information for 219 failures during 23-month period. Furthermore, it effectively identifies the triggering events with time and location information, even when the triggering events occur hundreds of hours before the resulting failures.« less

  8. Failures in Hybrid Microcircuits During Environmental Testing. History Cases

    NASA Technical Reports Server (NTRS)

    Teverovsky, Alexander

    2008-01-01

    This purpose of this viewgraph presentation is to discuss failures in hermetic hybrids observed at the GSFC PA Lab during environmental stress testing. The cases discussed are: Case I. Substrate metallization failures during Thermal cycling (TC). Case II. Flex lid-induced failure. Case Ill. Hermeticity failures during TC. Case IV. Die metallization cracking during TC. and how many test cycles and parts is necessary? Case V. Wire Bond failures after life test. Case VI. Failures caused by Au/In IMC growth.

  9. The role of resting duration in the kinematic pattern of two consecutive bench press sets to failure in elite sprint kayakers.

    PubMed

    García-López, D; Herrero, J A; Abadía, O; García-Isla, F J; Ualí, I; Izquierdo, M

    2008-09-01

    This study aimed to investigate the role of rest period duration (RP) on the time course of the acceleration portion (AP) and mean velocity of the concentric phase across two bench press sets to failure with a submaximal load (60% of the 1RM) using different RP. Ten elite junior kayakers performed, on four different days, two consecutive bench press sets to failure, allowing randomly 1-, 2-, 3- and 4-min RP between sets. AP reached a maximal value of 66% of the concentric movement time. This maximal AP was observed in repetition number 2 or 3, and then AP declined during the set, with a significant decrease when the number of repetitions was over 80% of the total number of repetitions performed. AP and lifting velocity patterns of the concentric phase were not altered during a second set to failure, regardless of RP. However, when velocity was expressed in absolute terms, 1-min RP was insufficient to maintain the average lifting velocity during the second set, compared to the first one. These results may be of use in selecting number of repetitions and resting duration in order to ensure optimal maintenance of the accelerative portion of concentric movement time with different resting-period durations.

  10. Bone marrow failure unresponsive to bone marrow transplant is caused by mutations in thrombopoietin.

    PubMed

    Seo, Aaron; Ben-Harosh, Miri; Sirin, Mehtap; Stein, Jerry; Dgany, Orly; Kaplelushnik, Joseph; Hoenig, Manfred; Pannicke, Ulrich; Lorenz, Myriam; Schwarz, Klaus; Stockklausner, Clemens; Walsh, Tom; Gulsuner, Suleyman; Lee, Ming K; Sendamarai, Anoop; Sanchez-Bonilla, Marilyn; King, Mary-Claire; Cario, Holger; Kulozik, Andreas E; Debatin, Klaus-Michael; Schulz, Ansgar; Tamary, Hannah; Shimamura, Akiko

    2017-08-17

    We report 5 individuals in 3 unrelated families with severe thrombocytopenia progressing to trilineage bone marrow failure (BMF). Four of the children received hematopoietic stem cell transplants and all showed poor graft function with persistent severe cytopenias even after repeated transplants with different donors. Exome and targeted sequencing identified mutations in the gene encoding thrombopoietin ( THPO ): THPO R99W, homozygous in affected children in 2 families, and THPO R157X, homozygous in the affected child in the third family. Both mutations result in a lack of THPO in the patients' serum. For the 2 surviving patients, improvement in trilineage hematopoiesis was achieved following treatment with a THPO receptor agonist. These studies demonstrate that biallelic loss-of-function mutations in THPO cause BMF, which is unresponsive to transplant due to a hematopoietic cell-extrinsic mechanism. These studies provide further support for the critical role of the MPL-THPO pathway in hematopoiesis and highlight the importance of accurate genetic diagnosis to inform treatment decisions for BMF. © 2017 by The American Society of Hematology.

  11. High-throughput sequencing: a failure mode analysis.

    PubMed

    Yang, George S; Stott, Jeffery M; Smailus, Duane; Barber, Sarah A; Balasundaram, Miruna; Marra, Marco A; Holt, Robert A

    2005-01-04

    Basic manufacturing principles are becoming increasingly important in high-throughput sequencing facilities where there is a constant drive to increase quality, increase efficiency, and decrease operating costs. While high-throughput centres report failure rates typically on the order of 10%, the causes of sporadic sequencing failures are seldom analyzed in detail and have not, in the past, been formally reported. Here we report the results of a failure mode analysis of our production sequencing facility based on detailed evaluation of 9,216 ESTs generated from two cDNA libraries. Two categories of failures are described; process-related failures (failures due to equipment or sample handling) and template-related failures (failures that are revealed by close inspection of electropherograms and are likely due to properties of the template DNA sequence itself). Preventative action based on a detailed understanding of failure modes is likely to improve the performance of other production sequencing pipelines.

  12. Failure-Modes-And-Effects Analysis Of Software Logic

    NASA Technical Reports Server (NTRS)

    Garcia, Danny; Hartline, Thomas; Minor, Terry; Statum, David; Vice, David

    1996-01-01

    Rigorous analysis applied early in design effort. Method of identifying potential inadequacies and modes and effects of failures caused by inadequacies (failure-modes-and-effects analysis or "FMEA" for short) devised for application to software logic.

  13. Bacteria causing bacteremia in pediatric cancer patients presenting with febrile neutropenia--species distribution and susceptibility patterns.

    PubMed

    Miedema, Karin G E; Winter, Rik H L J; Ammann, Roland A; Droz, Sara; Spanjaard, Lodewijk; de Bont, Eveline S J M; Kamps, Willem A; van de Wetering, Marianne D; Tissing, Wim J E

    2013-09-01

    Infections are a major cause of morbidity and mortality in pediatric cancer patients. The aim of this study was to establish the microbiological spectrum and the susceptibility patterns of bacteremia-causing bacteria in pediatric cancer patients with febrile neutropenia in relation to the use of prophylactic and empirical antibiotics. We analyzed positive blood cultures of pediatric cancer patients presenting with febrile neutropenia between 2004 and 2011 in Groningen and Amsterdam (the Netherlands) and in Bern (Switzerland), using different antibiotic prophylactic and empirical regimens. A total of 156 patients with 202 bacteremias, due to 248 bacteria species, were enrolled. The majority (73%) of bacteremias were caused by Gram-positive bacteria. Gram-negative bacteria, especially Pseudomonas aeruginosa, were observed significantly more often in Bern, where no fluoroquinolone prophylaxis was used. Ciprofloxacin-resistant bacteria were cultured more often from patients who did receive ciprofloxacin prophylaxis, compared to the patients who did not (57 versus 11%, p = 0.044). Gram-positive bacteria predominated in this study. We showed that the use of prophylactic antibiotics in pediatric cancer patients was associated with increased resistance rates, which needs further study. The strategy for empiric antimicrobial therapy for febrile neutropenia should be adapted to local antibiotic resistance patterns.

  14. Individual variation in prey selection by sea otters: Patterns, causes and implications

    USGS Publications Warehouse

    Estes, J.A.; Riedman, M.L.; Staedler, M.M.; Tinker, M.T.; Lyon, B.E.

    2003-01-01

    1. Longitudinal records of prey selection by 10 adult female sea otters on the Monterey Peninsula, California, from 1983 to 1990 demonstrate extreme inter-individual variation in diet. Variation in prey availability cannot explain these differences as the data were obtained from a common spatial-temporal area. 2. Individual dietary patterns persisted throughout our study, thus indicating that they are life-long characteristics. 3. Individual dietary patterns in sea otters appear to be transmitted along matrilines, probably by way of learning during the period of mother-young association. 4. Efficient utilization of different prey types probably requires radically different sensory/motor skills, each of which is difficult to acquire and all of which may exceed the learning and performance capacities of any single individual. This would explain the absence of generalists and inertia against switching, but not the existence of alternative specialists. 5. Such individual variation might arise in a constant environment from frequency-dependent effects, whereby the relative benefit of a given prey specialization depends on the number of other individuals utilizing that prey. Additionally, many of the sea otter's prey fluctuate substantially in abundance through time. This temporal variation, in conjunction with matrilineal transmission of foraging skills, may act to mediate the temporal dynamics of prey specializations. 6. Regardless of the exact cause, such extreme individual variation in diet has broad ramifications for population and community ecology. 7. The published literature indicates that similar patterns occur in many other species.

  15. All-cause and cause-specific mortality among US youth: socioeconomic and rural-urban disparities and international patterns.

    PubMed

    Singh, Gopal K; Azuine, Romuladus E; Siahpush, Mohammad; Kogan, Michael D

    2013-06-01

    We analyzed international patterns and socioeconomic and rural-urban disparities in all-cause mortality and mortality from homicide, suicide, unintentional injuries, and HIV/AIDS among US youth aged 15-24 years. A county-level socioeconomic deprivation index and rural-urban continuum measure were linked to the 1999-2007 US mortality data. Mortality rates were calculated for each socioeconomic and rural-urban group. Poisson regression was used to derive adjusted relative risks of youth mortality by deprivation level and rural-urban residence. The USA has the highest youth homicide rate and 6th highest overall youth mortality rate in the industrialized world. Substantial socioeconomic and rural-urban gradients in youth mortality were observed within the USA. Compared to their most affluent counterparts, youth in the most deprived group had 1.9 times higher all-cause mortality, 8.0 times higher homicide mortality, 1.5 times higher unintentional-injury mortality, and 8.8 times higher HIV/AIDS mortality. Youth in rural areas had significantly higher mortality rates than their urban counterparts regardless of deprivation levels, with suicide and unintentional-injury mortality risks being 1.8 and 2.3 times larger in rural than in urban areas. However, youth in the most urbanized areas had at least 5.6 times higher risks of homicide and HIV/AIDS mortality than their rural counterparts. Disparities in mortality differed by race and sex. Socioeconomic deprivation and rural-urban continuum were independently related to disparities in youth mortality among all sex and racial/ethnic groups, although the impact of deprivation was considerably greater. The USA ranks poorly in all-cause mortality, youth homicide, and unintentional-injury mortality rates when compared with other industrialized countries.

  16. Anabolic steroid-induced cardiomyopathy underlying acute liver failure in a young bodybuilder.

    PubMed

    Bispo, Miguel; Valente, Ana; Maldonado, Rosário; Palma, Rui; Glória, Helena; Nóbrega, João; Alexandrino, Paula

    2009-06-21

    Heart failure may lead to subclinical circulatory disturbances and remain an unrecognized cause of ischemic liver injury. We present the case of a previously healthy 40-year-old bodybuilder, referred to our Intensive-Care Unit of Hepatology for treatment of severe acute liver failure, with the suspicion of toxic hepatitis associated with anabolic steroid abuse. Despite the absence of symptoms and signs of congestive heart failure at admission, an anabolic steroid-induced dilated cardiomyopathy with a large thrombus in both ventricles was found to be the underlying cause of the liver injury. Treatment for the initially unrecognized heart failure rapidly restored liver function to normal. To our knowledge, this is the first reported case of severe acute liver failure due to an unrecognized anabolic steroid-induced cardiomyopathy. Awareness of this unique presentation will allow for prompt treatment of this potentially fatal cause of liver failure.

  17. Maternal and neonatal outcomes of respiratory failure during pregnancy.

    PubMed

    Hung, Chen-Yiu; Hu, Han-Chung; Chiu, Li-Chung; Chang, Chih-Hao; Li, Li-Fu; Huang, Chung-Chi; Kao, Chuan-Chi; Cheng, Po-Jen; Kao, Kuo-Chin

    2018-05-01

    Obstetric patients comprise a limited portion of intensive care unit patients, but they often present with unfamiliar conditions and exhibit the potential for catastrophic deterioration. This study evaluated the maternal and neonatal outcomes of respiratory failure during pregnancy. Information on 71 patients at >25 weeks gestation in the ICU with respiratory failure was recorded between 2009 and 2013. The characteristics and outcomes of mothers and fetuses were determined through a retrospective chart review and evaluated using Student's t test, chi-square test, and Fisher's exact test. The leading causes of respiratory failure were postpartum hemorrhage and severe preeclampsia in the obstetric causes group and pneumonia in the nonobstetric causes group during pregnancy and the peripartum period. The non-obstetric causes group exhibited a higher incidence of acute respiratory distress syndrome and renal replacement therapy as well as requiring more ventilator days. The patients in the obstetric causes group showed significant improvement after delivery in the partial pressure of arterial oxygen to the fraction of inspired oxygen and peak inspiratory pressure decrease. Both groups exhibited high incidences of neonatal respiratory distress syndrome. Neonatal complications resulting from meconium aspiration syndrome (MAS) and sepsis were more common in the non-obstetric causes group; however, neurological development impairment was more common in the obstetric causes group. Obstetric cause was associated with longer ventilator free days and fewer episodes of ARDS after delivery. Neonatal complications resulting from different etiologies of respiratory failure were found to differ. Copyright © 2017. Published by Elsevier B.V.

  18. Understanding the failure mechanisms of microwave bipolar transistors caused by electrostatic discharge

    NASA Astrophysics Data System (ADS)

    Jin, Liu; Yongguang, Chen; Zhiliang, Tan; Jie, Yang; Xijun, Zhang; Zhenxing, Wang

    2011-10-01

    Electrostatic discharge (ESD) phenomena involve both electrical and thermal effects, and a direct electrostatic discharge to an electronic device is one of the most severe threats to component reliability. Therefore, the electrical and thermal stability of multifinger microwave bipolar transistors (BJTs) under ESD conditions has been investigated theoretically and experimentally. 100 samples have been tested for multiple pulses until a failure occurred. Meanwhile, the distributions of electric field, current density and lattice temperature have also been analyzed by use of the two-dimensional device simulation tool Medici. There is a good agreement between the simulated results and failure analysis. In the case of a thermal couple, the avalanche current distribution in the fingers is in general spatially unstable and results in the formation of current crowding effects and crystal defects. The experimental results indicate that a collector-base junction is more sensitive to ESD than an emitter-base junction based on the special device structure. When the ESD level increased to 1.3 kV, the collector-base junction has been burnt out first. The analysis has also demonstrated that ESD failures occur generally by upsetting the breakdown voltage of the dielectric or overheating of the aluminum-silicon eutectic. In addition, fatigue phenomena are observed during ESD testing, with devices that still function after repeated low-intensity ESDs but whose performances have been severely degraded.

  19. Causes of Failure of High-Tensile Stud Bolts Used for Joining Metal Parts of Tower Crane

    NASA Astrophysics Data System (ADS)

    Tingaev, A. K.; Gubaydulin, R. G.; Shaburova, N. A.

    2017-11-01

    The causes of the failure of a high-tensile stud 2M48-6gx500 10.9 made from steel grade 30HGSA which led to a temporary inoperability of a tower crane were investigated. The bolts were used to assemble the tower sections and collapsed after 45 days from the moment the crane was commissioned. The cracks in the fracture are identified as fatigue with the characteristic sites of nucleation, sustainable development and static dolomite. To determine the possible causes of stud bolts destruction, metallographic, durometric and mechanical tests were carried out from which it follows that the stud bolt material in its original state corresponded to the delivery conditions. The destruction of the stud bolt appears to have resulted from a combination of several unfavorable factors: uncertainty about the actual tension of the stud bolt due to the lack of information about the magnitude of the twist factor; partial displacement of the centers of the brackets holes and rotation of the stud bolt axis during the sections’ assembly; no tight contact on the support surfaces of the section brackets. All this led to a discrepancy between the actual design of the stud bolt, the appearance of additional forces and the destruction of the stud bolt.

  20. A mid-layer model for human reliability analysis : understanding the cognitive causes of human failure events.

    SciTech Connect

    Shen, Song-Hua; Chang, James Y. H.; Boring,Ronald L.

    2010-03-01

    The Office of Nuclear Regulatory Research (RES) at the US Nuclear Regulatory Commission (USNRC) is sponsoring work in response to a Staff Requirements Memorandum (SRM) directing an effort to establish a single human reliability analysis (HRA) method for the agency or guidance for the use of multiple methods. As part of this effort an attempt to develop a comprehensive HRA qualitative approach is being pursued. This paper presents a draft of the method's middle layer, a part of the qualitative analysis phase that links failure mechanisms to performance shaping factors. Starting with a Crew Response Tree (CRT) that has identifiedmore » human failure events, analysts identify potential failure mechanisms using the mid-layer model. The mid-layer model presented in this paper traces the identification of the failure mechanisms using the Information-Diagnosis/Decision-Action (IDA) model and cognitive models from the psychological literature. Each failure mechanism is grouped according to a phase of IDA. Under each phase of IDA, the cognitive models help identify the relevant performance shaping factors for the failure mechanism. The use of IDA and cognitive models can be traced through fault trees, which provide a detailed complement to the CRT.« less

  1. Mediterranean Diet and Other Dietary Patterns in Primary Prevention of Heart Failure and Changes in Cardiac Function Markers: A Systematic Review.

    PubMed

    Sanches Machado d'Almeida, Karina; Ronchi Spillere, Stefanny; Zuchinali, Priccila; Corrêa Souza, Gabriela

    2018-01-10

    Heart failure (HF) is a complex syndrome and is recognized as the ultimate pathway of cardiovascular disease (CVD). Studies using nutritional strategies based on dietary patterns have proved to be effective for the prevention and treatment of CVD. Although there are studies that support the protective effect of these diets, their effects on the prevention of HF are not clear yet. We searched the Medline, Embase, and Cochrane databases for studies that examined dietary patterns, such as dietary approaches to stop hypertension (DASH diet), paleolithic, vegetarian, low-carb and low-fat diets and prevention of HF. No limitations were used during the search in the databases. A total of 1119 studies were identified, 14 met the inclusion criteria. Studies regarding the Mediterranean, DASH, vegetarian, and Paleolithic diets were found. The Mediterranean and DASH diets showed a protective effect on the incidence of HF and/or worsening of cardiac function parameters, with a significant difference in relation to patients who did not adhere to these dietary patterns. It is observed that the adoption of Mediterranean or DASH-type dietary patterns may contribute to the prevention of HF, but these results need to be analyzed with caution due to the low quality of evidence.

  2. Mediterranean Diet and Other Dietary Patterns in Primary Prevention of Heart Failure and Changes in Cardiac Function Markers: A Systematic Review

    PubMed Central

    Sanches Machado d’Almeida, Karina; Ronchi Spillere, Stefanny; Zuchinali, Priccila; Corrêa Souza, Gabriela

    2018-01-01

    Background: Heart failure (HF) is a complex syndrome and is recognized as the ultimate pathway of cardiovascular disease (CVD). Studies using nutritional strategies based on dietary patterns have proved to be effective for the prevention and treatment of CVD. Although there are studies that support the protective effect of these diets, their effects on the prevention of HF are not clear yet. Methods: We searched the Medline, Embase, and Cochrane databases for studies that examined dietary patterns, such as dietary approaches to stop hypertension (DASH diet), paleolithic, vegetarian, low-carb and low-fat diets and prevention of HF. No limitations were used during the search in the databases. Results: A total of 1119 studies were identified, 14 met the inclusion criteria. Studies regarding the Mediterranean, DASH, vegetarian, and Paleolithic diets were found. The Mediterranean and DASH diets showed a protective effect on the incidence of HF and/or worsening of cardiac function parameters, with a significant difference in relation to patients who did not adhere to these dietary patterns. Conclusions: It is observed that the adoption of Mediterranean or DASH-type dietary patterns may contribute to the prevention of HF, but these results need to be analyzed with caution due to the low quality of evidence. PMID:29320401

  3. [Pain, flare-ups and failures in root canal therapy].

    PubMed

    Moorer, W R

    1989-10-01

    In this overview the incidences and causes of pain, flare-ups and failures that occur after root canal therapy are discussed. Infection is considered the most important single, underlying determinant of the many factors that may cause pain and failures. Therefore, strict adherence to recognized therapeutic principles of shaping, disinfection and filling, in addition to proper aftercare, is of importance to diminish postoperative sequelae.

  4. Tin Whiskers: A History of Documented Electrical System Failures

    NASA Technical Reports Server (NTRS)

    Leidecker, Henning; Brusse, Jay

    2006-01-01

    This viewgraph presentation reviews the history of tin and other metal whiskers, and the damage they have caused equipment. There are pictures of whiskers on various pieces of electronic equipment, and microscopic views of whiskers. There is also a chart with information on the documented failures associated with metal whiskers. There are also examples of on-orbit failures believed to be caused by whiskers.

  5. In-hospital and 3-year outcomes of heart failure patients in South India: The Trivandrum Heart Failure Registry.

    PubMed

    Sanjay, Ganapathi; Jeemon, Panniyammakal; Agarwal, Anubha; Viswanathan, Sunitha; Sreedharan, Madhu; Govindan, Vijayaraghavan; Gopalan, Bahuleyan Charantharalyil; Biju, R; Nair, Tiny; Prathapkumar, N; Krishnakumar, G; Rajalekshmi, N; Suresh, Krishnan; Park, Lawrence P; Huffman, Mark D; Harikrishnan, Sivadasanpillai

    2018-06-06

    Long-term data on outcomes of participants hospitalized with heart failure (HF) from low and middle-income countries are limited. In the Trivandrum Heart Failure Registry (THFR) in 2013, 1205 participants from 18 hospitals in Trivandrum, India were enrolled. Data were collected on demographics, clinical presentation, treatment and outcomes. We performed survival analyses, compared groups and evaluated the association between HF type and mortality, adjusting for covariates that predicted mortality in a global HF risk score. The mean (SD) age of participants was 61.2 (13.7) years. Ischemic heart disease was the most common etiology (72%). In-hospital mortality was higher for participants with heart-failure with reduced ejection fraction (HFrEF) (9.7%) compared to those with heart-failure with preserved ejection fraction (HFpEF) (4.8%, p = 0.003). After three years, 540 (44.8%) of all participants had died. All-cause mortality was lower for participants with HFpEF (40.8%) compared to HFrEF (46.2%, p = 0.049). In multivariable models, older age (hazard ratio [HR] 1.24 per decade, 95% CI 1.15, 1.33), NYHA class-IV symptoms (HR 2.80, 95% CI 1.43, 5.48), and higher serum creatinine (HR 1.12 per mg/dl, 95%CI 1.04, 1.22) were associated with all-cause mortality. Participants with HF in the THFR have high three-year all-cause mortality. Targeted hospital-based quality improvement initiatives are needed to improve survival during and after hospitalization for heart failure. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Health professionals' migration in emerging market economies: patterns, causes and possible solutions.

    PubMed

    Nair, Manisha; Webster, Premila

    2013-03-01

    About a third of the countries affected by shortage of human resources for health are the emerging market economies (EMEs). The greatest shortage in absolute terms was found to be in India and Indonesia leading to health system crisis. This review identifies the patterns of migration of health workers, causes and possible solutions in these EMEs. A qualitative synthesis approach based on the 'critical review' and 'realist review' approaches to the literature review was used. The patterns of migration of health professionals' in the EMEs have led to two types of discrepancies between health needs and healthcare workers: (i) within country (rural-urban, public-private or government healthcare sector-private sector) and (ii) across countries (south to north). Factors that influence migration include lack of employment opportunities, appropriate work environment and wages in EMEs, growing demand in high-income countries due to demographic transition, favourable country policies for financial remittances by migrant workers and medical education system of EMEs. A range of successful national and international initiatives to address health workforce migration were identified. Measures to control migration should be country specific and designed in accordance with the push and pull factors existing in the EMEs.

  7. 12 CFR 1208.72 - Failure to appear.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 9 2012-01-01 2012-01-01 false Failure to appear. 1208.72 Section 1208.72 Banks and Banking FEDERAL HOUSING FINANCE AGENCY ORGANIZATION AND OPERATIONS DEBT COLLECTION Administrative Wage Garnishment § 1208.72 Failure to appear. In the absence of good cause shown, a debtor who...

  8. 12 CFR 1208.72 - Failure to appear.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 9 2013-01-01 2013-01-01 false Failure to appear. 1208.72 Section 1208.72 Banks and Banking FEDERAL HOUSING FINANCE AGENCY ORGANIZATION AND OPERATIONS DEBT COLLECTION Administrative Wage Garnishment § 1208.72 Failure to appear. In the absence of good cause shown, a debtor who...

  9. 12 CFR 1208.72 - Failure to appear.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 7 2011-01-01 2011-01-01 false Failure to appear. 1208.72 Section 1208.72 Banks and Banking FEDERAL HOUSING FINANCE AGENCY ORGANIZATION AND OPERATIONS DEBT COLLECTION Administrative Wage Garnishment § 1208.72 Failure to appear. In the absence of good cause shown, a debtor who...

  10. 12 CFR 1208.72 - Failure to appear.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 10 2014-01-01 2014-01-01 false Failure to appear. 1208.72 Section 1208.72 Banks and Banking FEDERAL HOUSING FINANCE AGENCY ORGANIZATION AND OPERATIONS DEBT COLLECTION Administrative Wage Garnishment § 1208.72 Failure to appear. In the absence of good cause shown, a debtor who...

  11. Failure modes of microstructured fibers with sacrificial bonds made by instability-assisted 3D printing

    NASA Astrophysics Data System (ADS)

    Zou, Shibo; Therriault, Daniel; Gosselin, Frederick

    A simple modification by increasing the deposition height on a commercially available 3D printer makes it a mechanical sewing machine due to the fluid mechanical instability. A variety of stitches-like patterns can be produced, similar to those by the Newtonian fluid mechanical sewing machine\\x9D, but with more interesting characteristics in the additional third dimension, which creates weakly fused bonds in some patterns. With these bonds, the fabricated fibers exhibit improved toughness in uniaxial tensile test. The toughening mechanism is found to be similar to the one in spider silk - the breaking of sacrificial bonds and the releasing of hidden length contribute significant dissipated energy to the system. However, the mechanical performance of these microstructured fibers is restricted by early fiber breakage as the number of sacrificial bonds increases. Here, we seek to understand the failure mechanisms of the microstructured fibers through tensile tests and finite element simulations. Static and dynamic failure are both found to cause early fiber breakage. These findings are helpful for the design optimization of microstructured fibers with high toughness and ductility, which can find potential use in impact protection and safety-critical applications.

  12. Management of failure after surgery for gastro-esophageal reflux disease.

    PubMed

    Gronnier, C; Degrandi, O; Collet, D

    2018-04-01

    Surgical treatment of gastro-esophageal reflux disease (ST-GERD) is well-codified and offers an alternative to long-term medical treatment with a better efficacy for short and long-term outcomes. However, failure of ST-GERD is observed in 2-20% of patients; management is challenging and not standardized. The aim of this study is to analyze the causes of failure and to provide a treatment algorithm. The clinical aspects of ST-GERD failure are variable including persistent reflux, dysphagia or permanent discomfort leading to an important degradation of the quality of life. A morphological and functional pre-therapeutic evaluation is necessary to: (i) determine whether the symptoms are due to recurrence of reflux or to an error in initial indication and (ii) to understand the cause of the failure. The most frequent causes of failure of ST-GERD include errors in the initial indication, which often only need medical treatment, and surgical technical errors, for which surgical redo surgery can be difficult. Multidisciplinary management is necessary in order to offer the best-adapted treatment. Copyright © 2018. Published by Elsevier Masson SAS.

  13. Lox/Gox related failures during Space Shuttle Main Engine development

    NASA Technical Reports Server (NTRS)

    Cataldo, C. E.

    1981-01-01

    Specific rocket engine hardware and test facility system failures are described which were caused by high pressure liquid and/or gaseous oxygen reactions. The failures were encountered during the development and testing of the space shuttle main engine. Failure mechanisms are discussed as well as corrective actions taken to prevent or reduce the potential of future failures.

  14. East Coast Fever Caused by Theileria parva Is Characterized by Macrophage Activation Associated with Vasculitis and Respiratory Failure.

    PubMed

    Fry, Lindsay M; Schneider, David A; Frevert, Charles W; Nelson, Danielle D; Morrison, W Ivan; Knowles, Donald P

    2016-01-01

    Respiratory failure and death in East Coast Fever (ECF), a clinical syndrome of African cattle caused by the apicomplexan parasite Theileria parva, has historically been attributed to pulmonary infiltration by infected lymphocytes. However, immunohistochemical staining of tissue from T. parva infected cattle revealed large numbers of CD3- and CD20-negative intralesional mononuclear cells. Due to this finding, we hypothesized that macrophages play an important role in Theileria parva disease pathogenesis. Data presented here demonstrates that terminal ECF in both Holstein and Boran cattle is largely due to multisystemic histiocytic responses and resultant tissue damage. Furthermore, the combination of these histologic changes with the clinical findings, including lymphadenopathy, prolonged pyrexia, multi-lineage leukopenia, and thrombocytopenia is consistent with macrophage activation syndrome. All animals that succumbed to infection exhibited lymphohistiocytic vasculitis of small to medium caliber blood and lymphatic vessels. In pulmonary, lymphoid, splenic and hepatic tissues from Holstein cattle, the majority of intralesional macrophages were positive for CD163, and often expressed large amounts of IL-17. These data define a terminal ECF pathogenesis in which parasite-driven lymphoproliferation leads to secondary systemic macrophage activation syndrome, mononuclear vasculitis, pulmonary edema, respiratory failure and death. The accompanying macrophage phenotype defined by CD163 and IL-17 is presented in the context of this pathogenesis.

  15. Fault tree analysis of most common rolling bearing tribological failures

    NASA Astrophysics Data System (ADS)

    Vencl, Aleksandar; Gašić, Vlada; Stojanović, Blaža

    2017-02-01

    Wear as a tribological process has a major influence on the reliability and life of rolling bearings. Field examinations of bearing failures due to wear indicate possible causes and point to the necessary measurements for wear reduction or elimination. Wear itself is a very complex process initiated by the action of different mechanisms, and can be manifested by different wear types which are often related. However, the dominant type of wear can be approximately determined. The paper presents the classification of most common bearing damages according to the dominant wear type, i.e. abrasive wear, adhesive wear, surface fatigue wear, erosive wear, fretting wear and corrosive wear. The wear types are correlated with the terms used in ISO 15243 standard. Each wear type is illustrated with an appropriate photograph, and for each wear type, appropriate description of causes and manifestations is presented. Possible causes of rolling bearing failure are used for the fault tree analysis (FTA). It was performed to determine the root causes for bearing failures. The constructed fault tree diagram for rolling bearing failure can be useful tool for maintenance engineers.

  16. Mathematics, Questions, and "Schools Without Failure"

    ERIC Educational Resources Information Center

    Perl, Teri

    1974-01-01

    Most questions in the mathematics classroom deal with memorization and learning, and have one correct answer. Suggestions for using three other types of questions identified by Glasser (SCHOOLS WITHOUT FAILURE) are provided. Activities discussed include tangrams, attribute blocks, pattern recognition, and games. (SD)

  17. Patient Characteristics, Health Care Resource Utilization, and Costs Associated with Treatment-Regimen Failure with Biologics in the Treatment of Psoriasis.

    PubMed

    Foster, Shonda A; Zhu, Baojin; Guo, Jiaying; Nikai, Enkeleida; Ojeh, Clement; Malatestinic, William; Goldblum, Orin; Kornberg, Lori J; Wu, Jashin J

    2016-04-01

    variance for continuous variables and chi-square tests for categorical variables without adjustment. Cost differences were compared using the propensity score-adjusted bin bootstrapping method. Overall, 2,146 patients met the enrollment criteria. The mean age was 45.1 years. Of these patients, 41.5% were considered treatment-regimen failures. Among treatment-regimen failures, 53% were females, and among non-treatment-regimen failures, 61% were male. Patients who experienced treatment-regimen failure had higher incidences of comorbid cerebrovascular disease, hypertension, chronic pulmonary disease, depression, and anxiety in the pre-index period and were more likely to use concomitant topicals (67.0% vs. 58.4%; P < 0.001), methotrexate (20.2% vs. 7.3%; P < 0.001), and cyclosporine (3.1% vs. 1.0%; P < 0.001) in the post-index period. Mean total all-cause health care costs were higher in patients with treatment-regimen failure versus non-treatment-regimen failure during the pre-index period ($8,024 vs. $6,637; P = 0.002), but patients with non-treatment-regimen failure had higher all-cause costs ($30,759 vs. $28,012; P = 0.002) and psoriasis-related costs ($25,286 vs. $19,625; P < 0.001) during the post-index period. The results of the current study demonstrated that psoriasis patients with treatment patterns suggestive of treatment-regimen failure on an index biologic had different characteristics and incurred higher all-cause health care costs than did patients without treatment-regimen failure during the pre-index period. This study was supported by Eli Lilly and Company. Foster, Zhu, Guo, Nikai, Malatestinic, Ojeh, and Goldblum are full-time employees and stockholders of Eli Lilly and Company. Kornberg is a full-time employee of INC Research, which was contracted by Eli Lilly to assist with medical writing. Wu has received research funding from AbbVie, Amgen, Coherus Biosciences, Eli Lilly, Janssen, Merck, Novartis, Pfizer, Regeneron, and Sandoz; he is a consultant for

  18. Particles causing lung disease

    SciTech Connect

    Kilburn, K.H.

    1984-04-01

    The lung has a limited number of patterns of reaction to inhaled particles. The disease observed depends upon the location: conducting airways, terminal bronchioles and alveoli, and upon the nature of inflammation induced: acute, subacute or chronic. Many different agents cause narrowing of conducting airways (asthma) and some of these cause permanent distortion or obliteration of airways as well. Terminal bronchioles appear to be particularly susceptible to particles which cause goblet cell metaplasia, mucous plugging and ultimately peribronchiolar fibrosis. Cancer is the last outcome at the bronchial level and appears to depend upon continuous exposure to or retention of anmore » agent in the airway and failure of the affected cells to be exfoliated which may be due to squamous metaplasia. Alveoli are populated by endothelial cells, Type I or pavement epithelial cells and metabolically active cuboidal Type II cells that produce the lungs specific surfactant, dipalmytol lecithin. Disturbances of surfactant lead to edema in distal lung while laryngeal edema due to anaphylaxis or fumes may produce asphyxia. Physical retention of indigestible particles or retention by immune memory responses may provoke hyaline membranes, stimulate alveolar lipoproteinosis and finally fibrosis. This later exuberant deposition of connective tissue has been best studied in the occupational pneumoconioses especially silicosis and asbestosis. In contrast emphysema a catabolic response appears frequently to result from leakage or release of lysosomal proteases into the lung during processing of cigarette smoke particles. 164 references, 1 figure, 2 tables.« less

  19. Progressive Failure Analysis Methodology for Laminated Composite Structures

    NASA Technical Reports Server (NTRS)

    Sleight, David W.

    1999-01-01

    A progressive failure analysis method has been developed for predicting the failure of laminated composite structures under geometrically nonlinear deformations. The progressive failure analysis uses C(exp 1) shell elements based on classical lamination theory to calculate the in-plane stresses. Several failure criteria, including the maximum strain criterion, Hashin's criterion, and Christensen's criterion, are used to predict the failure mechanisms and several options are available to degrade the material properties after failures. The progressive failure analysis method is implemented in the COMET finite element analysis code and can predict the damage and response of laminated composite structures from initial loading to final failure. The different failure criteria and material degradation methods are compared and assessed by performing analyses of several laminated composite structures. Results from the progressive failure method indicate good correlation with the existing test data except in structural applications where interlaminar stresses are important which may cause failure mechanisms such as debonding or delaminations.

  20. Association Between Use of Long-Acting Nitrates and Outcomes in Heart Failure With Preserved Ejection Fraction.

    PubMed

    Lim, Shir Lynn; Benson, Lina; Dahlström, Ulf; Lam, Carolyn S P; Lund, Lars H

    2017-04-01

    Nitrates may be beneficial in heart failure with preserved ejection fraction (HFpEF) by enhancing cGMP signaling and improving hemodynamics, but real-world data on potential efficacy are lacking. We linked the Swedish Heart Failure Registry to national registries with International Classification of Diseases, Tenth Revision comorbidity diagnoses and demographic and socioeconomic data. In HFpEF, defined as left ventricular ejection fraction ≥40%, we derived propensity scores for nitrate use using 52 baseline variables. The association between nitrate use and all-cause mortality and the composite of all-cause mortality or first heart failure hospitalization was assessed in a cohort matched 2:1 untreated to treated based on age and propensity score. In the overall HFpEF cohort (n=19 047; mean [SD] age, 76 [12] years; 46% women), nitrates were used in 17%, and the crude 1-year survival for treated versus untreated patients was 79% (95% confidence interval [CI], 78%-80%) versus 84% (95% CI, 83%-84%) respectively; hazard ratio was 1.48 (95% CI, 1.40-1.56; P <0.001) during a median 755-day follow-up. Matching yielded 2235 treated versus 4470 untreated patients, with 1-year survival of 80% (95% CI, 78%-82%) versus 79% (95% CI, 78%-81%) and hazard ratio of 1.06 (95% CI, 0.98-1.15; P =0.12). Nitrates were associated with worse composite outcome in the matched HFpEF cohort, with 1-year event-free survival of 62% (95% CI, 60%-64%) versus 65% (95% CI, 63%-66%) and hazard ratio of 1.11 (95% CI, 1.04-1.18; P =0.003). These patterns were reproduced in several consistency analyses. In HFpEF, the use of nitrates was not associated with improvements in all-cause mortality or heart failure hospitalization. © 2017 American Heart Association, Inc.

  1. The Genetic Challenges and Opportunities in Advanced Heart Failure

    PubMed Central

    Hannah-Shmouni, Fady; Seidelmann, Sara B.; Sirrs, Sandra; Mani, Arya; Jacoby, Daniel

    2017-01-01

    The causes of heart failure are diverse. Inherited causes represent an important clinical entity and can be divided into 2 major categories: familial and metabolic cardiomyopathies. The distinct features that might be present in early disease states can become broadly overlapping with other diseases, such as in the case of inherited cardiomyopathies (ie, familial hypertrophic cardiomyopathy or mitochondrial diseases). In this review article, we focus on genetic issues related to advanced heart failure. Because of the emerging importance of this topic and its breadth, we sought to focus our discussion on the known genetic forms of heart failure syndromes, genetic testing, and newer data on pharmacogenetics and therapeutics in the treatment of heart failure, to primarily encourage clinicians to place a priority on the diagnosis and treatment of these potentially treatable conditions. PMID:26518444

  2. Key performance outcomes of patient safety curricula: root cause analysis, failure mode and effects analysis, and structured communications skills.

    PubMed

    Fassett, William E

    2011-10-10

    As colleges and schools of pharmacy develop core courses related to patient safety, course-level outcomes will need to include both knowledge and performance measures. Three key performance outcomes for patient safety coursework, measured at the course level, are the ability to perform root cause analyses and healthcare failure mode effects analyses, and the ability to generate effective safety communications using structured formats such as the Situation-Background-Assessment-Recommendation (SBAR) situational briefing model. Each of these skills is widely used in patient safety work and competence in their use is essential for a pharmacist's ability to contribute as a member of a patient safety team.

  3. Meta-Analysis of the Associations of p-Cresyl Sulfate (PCS) and Indoxyl Sulfate (IS) with Cardiovascular Events and All-Cause Mortality in Patients with Chronic Renal Failure.

    PubMed

    Lin, Cheng-Jui; Wu, Vincent; Wu, Pei-Chen; Wu, Chih-Jen

    2015-01-01

    Indoxyl sulfate (IS) and p-cresyl sulfate (PCS) are protein-bound uremic toxins that increase in the sera of patients with chronic kidney disease (CKD), and are not effectively removed by dialysis. The purpose of this meta-analysis was to investigate the relationships of PCS and IS with cardiovascular events and all-cause mortality in patients with CKD stage 3 and above. Medline, Cochrane, and EMBASE databases were searched until January 1, 2014 with combinations of the following keywords: chronic renal failure, end-stage kidney disease, uremic toxin, uremic retention, indoxyl sulfate, p-cresyl sulfate. Inclusion criteria were: 1) Patients with stage 1 to 5 CKD; 2) Prospective study; 3) Randomized controlled trial; 4) English language publication. The associations between serum levels of PCS and IS and the risks of all-cause mortality and cardiovascular events were the primary outcome measures. Of 155 articles initially identified, 10 prospective and one cross-sectional study with a total 1,572 patients were included. Free PCS was significantly associated with all-cause mortality among patients with chronic renal failure (pooled OR = 1.16, 95% CI = 1.03 to 1.30, P = 0.013). An elevated free IS level was also significantly associated with increased risk of all-cause mortality (pooled OR = 1.10, 95% CI = 1.03 to 1.17, P = 0.003). An elevated free PCS level was significantly associated with an increased risk of cardiovascular events among patients with chronic renal failure (pooled OR = 1.28, 95% CI = 1.10 to 1.50, P = 0.002), while free IS was not significantly associated with risk of cardiovascular events (pooled OR = 1.05, 95% CI = 0.98 to 1.13, P = 0.196). Elevated levels of PCS and IS are associated with increased mortality in patients with CKD, while PCS, but not IS, is associated with an increased risk of cardiovascular events.

  4. Comparison of frequencies of left ventricular systolic and diastolic heart failure in Chinese living in Hong Kong.

    PubMed

    Yip, G W; Ho, P P; Woo, K S; Sanderson, J E

    1999-09-01

    There is a wide variation (13% to 74%) in the reported prevalence of heart failure associated with normal left ventricular (LV) systolic function (diastolic heart failure). There is no published information on this condition in China. To ascertain the prevalence of diastolic heart failure in this community, 200 consecutive patients with the typical features of congestive heart failure were studied with standard 2-dimensional Doppler echocardiography. A LV ejection fraction (LVEF) >45% was considered normal. The results showed that 12.5% had significant valvular heart disease. Of the remaining 175 patients, 132 had a LVEF >45% (75%). Therefore, 66% of patients with a clinical diagnosis of heart failure had a normal LVEF. Heart failure with normal LV systolic function was more common than systolic heart failure in those >70 years old (65% vs 47%; p = 0.015). Most (57%) had an abnormal relaxation pattern in diastole and 14% had a restrictive filling pattern. In the systolic heart failure group, a restrictive filling pattern was more common (46%). There were no significant differences in the sex distribution, etiology, or prevalence of LV hypertrophy between these 2 heart failure groups. In conclusion, heart failure with a normal LVEF or diastolic heart failure is more common than systolic heart failure in Chinese patients with the symptoms of heart failure. This may be related to older age at presentation and the high prevalence of hypertension in this community.

  5. Failure modes of Y-TZP abutments with external hex implant-abutment connection determined by fractographic analysis.

    PubMed

    Basílio, Mariana de Almeida; Delben, Juliana Aparecida; Cesar, Paulo Francisco; Rizkalla, Amin Sami; Santos Junior, Gildo Coelho; Arioli Filho, João Neudenir

    2016-07-01

    Yttria-stabilized tetragonal zirconia (Y-TZP) was introduced as ceramic implant abutments due to its excellent mechanical properties. However, the damage patterns for Y-TZP abutments are limited in the literature. Fractographic analyses can provide insights as to the failure origin and related mechanisms. The purpose of this study was to analyze fractured Y-TZP abutments to establish fractographic patterns and then possible reasons for failure. Thirty two prefabricated Y-TZP abutments on external hex implants were retrieved from a single-load-to failure test according to the ISO 14801. Fractographic analyses were conducted under polarized-light estereo and scanning electro microscopy. The predominant fracture pattern was abutment fracture at the connecting region. Classic fractographic features such as arrest lines, hackle, and twist hackle established that failure started where Y-TZP abutments were in contact with the retention screw edges. The abutment screw design and the loading point were the reasons for localized stress concentration and fracture patterns. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Management of Arrhythmias in Heart Failure

    PubMed Central

    Masarone, Daniele; Limongelli, Giuseppe; Rubino, Marta; Valente, Fabio; Vastarella, Rossella; Ammendola, Ernesto; Gravino, Rita; Verrengia, Marina; Salerno, Gemma; Pacileo, Giuseppe

    2017-01-01

    Heart failure patients are predisposed to develop arrhythmias. Supraventricular arrhythmias can exacerbate the heart failure symptoms by decreasing the effective cardiac output and their control require pharmacological, electrical, or catheter-based intervention. In the setting of atrial flutter or atrial fibrillation, anticoagulation becomes paramount to prevent systemic or cerebral embolism. Patients with heart failure are also prone to develop ventricular arrhythmias that can present a challenge to the managing clinician. The management strategy depends on the type of arrhythmia, the underlying structural heart disease, the severity of heart failure, and the range from optimization of heart failure therapy to catheter ablation. Patients with heart failure, irrespective of ejection fraction are at high risk for developing sudden cardiac death, however risk stratification is a clinical challenge and requires a multiparametric evaluation for identification of patients who should undergo implantation of a cardioverter defibrillator. Finally, patients with heart failure can also develop symptomatic bradycardia, caused by sinus node dysfunction or atrio-ventricular block. The treatment of bradycardia in these patients with pacing is usually straightforward but needs some specific issue. PMID:29367535

  7. Heart Failure in Sub-Saharan Africa

    PubMed Central

    Bloomfield, Gerald S; Barasa, Felix A; Doll, Jacob A; Velazquez, Eric J

    2013-01-01

    The heart failure syndrome has been recognized as a significant contributor to cardiovascular disease burden in sub-Saharan African for many decades. Seminal knowledge regarding heart failure in the region came from case reports and case series of the early 20th century which identified infectious, nutritional and idiopathic causes as the most common. With increasing urbanization, changes in lifestyle habits, and ageing of the population, the spectrum of causes of HF has also expanded resulting in a significant burden of both communicable and non-communicable etiologies. Heart failure in sub-Saharan Africa is notable for the range of etiologies that concurrently exist as well as the healthcare environment marked by limited resources, weak national healthcare systems and a paucity of national level data on disease trends. With the recent publication of the first and largest multinational prospective registry of acute heart failure in sub-Saharan Africa, it is timely to review the state of knowledge to date and describe the myriad forms of heart failure in the region. This review discusses several forms of heart failure that are common in sub-Saharan Africa (e.g., rheumatic heart disease, hypertensive heart disease, pericardial disease, various dilated cardiomyopathies, HIV cardiomyopathy, hypertrophic cardiomyopathy, endomyocardial fibrosis, ischemic heart disease, cor pulmonale) and presents each form with regard to epidemiology, natural history, clinical characteristics, diagnostic considerations and therapies. Areas and approaches to fill the remaining gaps in knowledge are also offered herein highlighting the need for research that is driven by regional disease burden and needs. PMID:23597299

  8. Circulating nucleic acids as possible damage-associated molecular patterns in different stages of renal failure.

    PubMed

    Kocić, Gordana; Radenkovic, Sonja; Cvetkovic, Tatjana; Cencic, Avrelija; Carluccio, Francesco; Musovic, Dijana; Nikolić, Goran; Jevtović-Stoimenov, Tatjana; Sokolović, Dusan; Milojkovic, Boban; Basic, Jelena; Veljkovic, Andrej; Stojanović, Svetlana

    2010-05-01

    Chronic renal failure (CRF) is a condition associated with the risk of cardiovascular complications. Systemic inflammatory response, initiated by the pathogen-associated molecular-pattern (PAMP) molecules, exerts many similarities with the damage-associated molecular-pattern (DAMP) molecule-induced systemic response. Up to now, a number of DAMP molecules were identified. We hypothesized that the available circulating nucleic acids, acting as DAMPs, may modulate immunoinflammatory reaction in CRF. Patients with the different stages of chronic kidney disease, kidney transplantation, and patients on dialysis were included in the study. Obtained results about higher concentration of circulating ribonucleic acid (RNA), according to the stages of kidney diseases, may contribute to the hypothesis that damaged kidney tissue releases nucleic acids. Circulating RNAs expressed maximal absorbance peak at 270 nm in spectrophotometric scan analysis, which corresponded to polyC, compared to different standard samples. During in vitro conditions, by using the culture of human residential macrophages, circulating RNA isolated from patients with IV-V-stage renal diseases, patients on hemodialysis, and patients who underwent renal transplantation were able to significantly change signal transduction proteins related to inflammation and antiviral response. They significantly increased the intracellular concentration of active nuclear transcription factor nuclear factor kappa B (NF-kappaB), interferon regulatory factors (IRF)-3, and IRF-7 and significantly decreased melanoma differentiation-associated protein-5 (MDA-5) and p38. In this way, it seems that circulating RNA, acting as DAMP, may contribute to the mechanisms of additional inflammatory reaction, possible immune destruction, and decreased antiviral response, related to complications in kidney diseases.

  9. Vibrational fatigue failures in short cantilevered piping with socket-welding fittings

    SciTech Connect

    Smith, J.K.

    1996-12-01

    Approximately 80% of the vibrational fatigue failures in nuclear power plants have been caused by high cycle vibrational fatigue. Many of these failures have occurred in short, small bore (2 in. nominal diameter and smaller), unbraced, cantilevered piping with socket-welding fittings. The fatigue failures initiated in the socket welds. These failures have been unexpected, and have caused costly, unscheduled outages in some cases. In order to reduce the number of vibrational fatigue failures in these short cantilevered pipes, an acceleration based vibrational fatigue screening criteria was developed under Electric Power Research Institute (EPRI) sponsorship. In this paper, the acceleration basedmore » criteria will be compared to the results obtained from detailed dynamic modeling of a short, cantilevered pipe.« less

  10. Identifying Clinical Factors Which Predict for Early Failure Patterns Following Resection for Pancreatic Adenocarcinoma in Patients Who Received Adjuvant Chemotherapy Without Chemoradiation.

    PubMed

    Walston, Steve; Salloum, Joseph; Grieco, Carmine; Wuthrick, Evan; Diaz, Dayssy A; Barney, Christian; Manilchuk, Andrei; Schmidt, Carl; Dillhoff, Mary; Pawlik, Timothy M; Williams, Terence M

    2018-05-04

    The role of radiation therapy (RT) in resected pancreatic cancer (PC) remains incompletely defined. We sought to determine clinical variables which predict for local-regional recurrence (LRR) to help select patients for adjuvant RT. We identified 73 patients with PC who underwent resection and adjuvant gemcitabine-based chemotherapy alone. We performed detailed radiologic analysis of first patterns of failure. LRR was defined as recurrence of PC within standard postoperative radiation volumes. Univariate analyses (UVA) were conducted using the Kaplan-Meier method and multivariate analyses (MVA) utilized the Cox proportional hazard ratio model. Factors significant on UVA were used for MVA. At median follow-up of 20 months, rates of local-regional recurrence only (LRRO) were 24.7%, LRR as a component of any failure 68.5%, metastatic recurrence (MR) as a component of any failure 65.8%, and overall disease recurrence (OR) 90.5%. On UVA, elevated postoperative CA 19-9 (>90 U/mL), pathologic lymph node positive (pLN+) disease, and higher tumor grade were associated with increased LRR, MR, and OR. On MVA, elevated postoperative CA 19-9 and pLN+ were associated with increased MR and OR. In addition, positive resection margin was associated with increased LRRO on both UVA and MVA. About 25% of patients with PC treated without adjuvant RT develop LRRO as initial failure. The only independent predictor of LRRO was positive margin, while elevated postoperative CA 19-9 and pLN+ were associated with predicting MR and overall survival. These data may help determine which patients benefit from intensification of local therapy with radiation.

  11. Probable chronic renal failure caused by Lonomia caterpillar envenomation

    PubMed Central

    2013-01-01

    Erucism is a skin reaction to envenomation from certain poisonous caterpillar bristles. In Brazil, most reports of erucism provoked by Lonomia caterpillars are from the southern region. Most manifestations of erucism are local and include burning pain, itching, local hyperthermia and, rarely, blisters (benign symptoms with spontaneous regression in a few hours). General symptoms such as nausea and vomiting, headache, fever, myalgia, abdominal pain and conjunctivitis may also occur. Uncommon symptoms include arthritis, coagulation disorders (manifested as bruising and bleeding), intracerebral hemorrhage and acute renal failure, which comprise serious complications. The present study reports the case of 60-year-old patient from Rio de Janeiro state, Brazil, who came into contact with a caterpillar and developed, a few days later, chronic renal disease. PMID:23849585

  12. Correlated seed failure as an environmental veto to synchronize reproduction of masting plants.

    PubMed

    Bogdziewicz, Michał; Steele, Michael A; Marino, Shealyn; Crone, Elizabeth E

    2018-07-01

    Variable, synchronized seed production, called masting, is a widespread reproductive strategy in plants. Resource dynamics, pollination success, and, as described here, environmental veto are possible proximate mechanisms driving masting. We explored the environmental veto hypothesis, which assumes that reproductive synchrony is driven by external factors preventing reproduction in some years, by extending the resource budget model of masting with correlated reproductive failure. We ran this model across its parameter space to explore how key parameters interact to drive seeding dynamics. Next, we parameterized the model based on 16 yr of seed production data for populations of red (Quercus rubra) and white (Quercus alba) oaks. We used these empirical models to simulate seeding dynamics, and compared simulated time series with patterns observed in the field. Simulations showed that resource dynamics and reproduction failure can produce masting even in the absence of pollen coupling. In concordance with this, in both oaks, among-year variation in resource gain and correlated reproductive failure were necessary and sufficient to reproduce masting, whereas pollen coupling, although present, was not necessary. Reproductive failure caused by environmental veto may drive large-scale synchronization without density-dependent pollen limitation. Reproduction-inhibiting weather events are prevalent in ecosystems, making described mechanisms likely to operate in many systems. © 2018 The Authors New Phytologist © 2018 New Phytologist Trust.

  13. New Medications for Heart Failure

    PubMed Central

    Gordin, Jonathan S.; Fonarow, Gregg C.

    2016-01-01

    Heart failure is common and results in substantial morbidity and mortality. Current guideline-based therapies for heart failure with reduced ejection fraction, including beta-blockers, angiotensin converting enzyme (ACE) inhibitors, and aldosterone antagonists aim to interrupt deleterious neurohormonal pathways and have shown significant success in reducing morbidity and mortality associated with heart failure. Continued efforts to further improve outcomes in patients with heart failure with reduced ejection fraction have led to the first new-in-class medications approved for heart failure since 2005, ivabradine and sacubitril/valsartan. Ivabradine targets the If channels in the sinoatrial node of the heart, decreasing heart rate. Sacubitril/valsartan combines a neprilysin inhibitor that increases levels of beneficial vasodilatory peptides with an angiotensin receptor antagonist. On a background of previously approved, guideline-directed medical therapies for heart failure, these medications have shown improved clinical outcomes ranging from decreased hospitalizations in a select group of patients to a reduction in all-cause mortality across all pre-specified subgroups. In this review, we will discuss the previously established guideline-directed medical therapies for heart failure with reduced ejection fraction, the translational research that led to the development of these new therapies, and the results from the major clinical trials of ivabradine and sacubitril/valsartan. PMID:27038558

  14. Meta-analysis of the effects of carvedilol versus metoprolol on all-cause mortality and hospitalizations in patients with heart failure.

    PubMed

    Briasoulis, Alexandros; Palla, Mohan; Afonso, Luis

    2015-04-15

    Long-term treatment with appropriate doses of carvedilol or metoprolol is currently recommended for patients with heart failure with reduced ejection fraction (HFrEF) to decrease the risk of death, hospitalizations, and patients' symptoms. It remains unclear if the β blockers used in patients with HFrEF are equal or carvedilol is superior to metoprolol types. We performed a meta-analysis of the comparative effects of carvedilol versus metoprolol tartrate and succinate on all-cause mortality and/or hospitalization. We conducted an Embase and MEDLINE search for prospective controlled trials and cohort studies of patients with HFrEF who were received to treatment with carvedilol versus metoprolol. We identified 4 prospective controlled and 6 cohort studies with 30,943 patients who received carvedilol and 69,925 patients on metoprolol types (tartrate and succinate) with an average follow-up duration of 36.4 months. All-cause mortality was reduced in prospective studies with carvedilol versus metoprolol tartrate. Neither all-cause mortality nor hospitalizations were significantly different between carvedilol and metoprolol succinate in the cohort studies. In conclusion, in patients with HFrEF, carvedilol and metoprolol succinate have similar effects in reducing all-cause mortality. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Co-Constructed Failure Narratives in Mathematics Tutoring

    ERIC Educational Resources Information Center

    DeLiema, David

    2017-01-01

    The ideas students have about what causes math failure are known to impact motivation. This paper throws light on how attributions of failure are negotiated during math tutoring, between 4th/5th graders and volunteer tutors, at a non-profit STEM-based after-school program. The study employs methods of interaction analysis on a small number of…

  16. The annual global economic burden of heart failure.

    PubMed

    Cook, Christopher; Cole, Graham; Asaria, Perviz; Jabbour, Richard; Francis, Darrel P

    2014-02-15

    Heart failure (HF) imposes both direct costs to healthcare systems and indirect costs to society through morbidity, unpaid care costs, premature mortality and lost productivity. The global economic burden of HF is not known. We estimated the overall cost of heart failure in 2012, in both direct and indirect terms, across the globe. Existing country-specific heart failure costs analyses were expressed as a proportion of gross domestic product and total healthcare spend. Using World Bank data, these proportional values were used to interpolate the economic cost of HF for countries of the world where no published data exists. Countries were categorized according to their level of economic development to investigate global patterns of spending. 197 countries were included in the analysis, covering 98.7% of the world's population. The overall economic cost of HF in 2012 was estimated at $108 billion per annum. Direct costs accounted for ~60% ($65 billion) and indirect costs accounted for ~40% ($43 billion) of the overall spend. Heart failure spending varied widely between high-income and middle and low-income countries. High-income countries spend a greater proportion on direct costs: a pattern reversed for middle and low-income countries. Heart failure imposes a huge economic burden, estimated at $108 billion per annum. With an aging, rapidly expanding and industrializing global population this value will continue to rise. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  17. Prevalence and Mutation Patterns of HIV Drug Resistance from 2010 to 2011 among ART-Failure Individuals in the Yunnan Province, China

    PubMed Central

    Guo, Wei; Zhuang, Daomin; Li, Lin; Liu, Yongjian; Bao, Zuoyi; Liu, Siyang; Wang, Xiaolin; Li, Tianyi; Yang, Shaomin; Li, Jingyun

    2013-01-01

    Background Assessing the prevalence of HIV-1 drug-resistance and the mutation patterns associated with resistance in the geographical regions implementing free antiretroviral therapy (ART) in China is necessary for preventing the spread of resistant strains and designing the regimens for the subsequent therapies with limited resources. Methods Plasma samples in different cities/prefectures were collected at Yunnan Provincial Hospital of Infectious Disease from January 2010 to December 2011. Genotyping of drug-resistant individuals was conducted using an in-house assay on plasma samples. Viral load, CD4 T cell counts and demographic data were obtained from medical records and an administered questionnaire. Results A total of 609 pol sequences (515 ART-failure and 94 therapy-naïve individuals) derived from 664 samples were obtained. The prevalence of drug-resistance was 45.1% in the ART-failure individuals. Of these, 26.8% harbored HIV strains dually resistant to nucleoside reverse transcriptase inhibitors and non-nucleoside reverse transcriptase inhibitors, and 14.8% harbored HIV strains resistant to only one drug category. Mutations such as M184V/I, K103N, V106A, Y181C and G190A were common among the ART-failure individuals, and the frequencies of M184V/I, K103N and V106A were 28.2%, 19.2%, and 22.1%, respectively. The percentages of individuals exhibiting intermediate or high-level resistance to 3TC, FTC, EFV and NVP drugs were 28.4%, 28.2%, 37.3%, and 37.5%, respectively. Factors such as ethnicity, transmission route, CD4 counts, viral load and the duration of ART were significantly correlated with development of drug resistance in the ART-failure individuals. Conclusions The high prevalence of HIV drug-resistance observed among the ART-failure individuals from 2010 to 2011 in Yunnan province should be of increasing concern in regions where the implementation of ART is widespread. Education about the risk factors associated with HIV drug resistance is important

  18. Pheochromocytoma presenting with rhabdomyolysis and acute renal failure: a case report.

    PubMed

    Celik, Huseyin; Celik, Ozlem; Guldiken, Sibel; Inal, Volkan; Puyan, Fulya Oz; Tugrul, Armagan

    2014-02-01

    Rhabdomyolysis ranges from an asymptomatic illness with elevated creatine kinase levels to a life-threatening condition associated with extreme elevations in creatine kinase, electrolyte imbalances, acute renal failure, and disseminated intravascular coagulation. The most common causes are crush injury, overexertion, alcohol abuse, certain medicines, and toxic substances. A number of electrolyte abnormalities and endocrinopathies, including hypothyroidism, thyrotoxicosis, diabetic ketoacidosis, nonketotic hyperosmolar state, and hyperaldosteronism, cause rhabdomyolysis. Rhabdomyolysis and acute renal failure are unusual manifestations of pheochromocytoma. There are a few case reports with pheochromocytoma presenting rhabdomyolysis and acute renal failure. Herein, we report a case with pheochromocytoma crisis presenting with rhabdomyolysis and acute renal failure.

  19. Celiac Node Failure Patterns After Definitive Chemoradiation for Esophageal Cancer in the Modern Era

    SciTech Connect

    Amini, Arya; UC Irvine School of Medicine, Irvine, California; Xiao Lianchun

    2012-06-01

    Purpose: The celiac lymph node axis acts as a gateway for metastatic systemic spread. The need for prophylactic celiac nodal coverage in chemoradiation therapy for esophageal cancer is controversial. Given the improved ability to evaluate lymph node status before treatment via positron emission tomography (PET) and endoscopic ultrasound, we hypothesized that prophylactic celiac node irradiation may not be needed for patients with localized esophageal carcinoma. Methods and Materials: We reviewed the radiation treatment volumes for 131 patients who underwent definitive chemoradiation for esophageal cancer. Patients with celiac lymph node involvement at baseline were excluded. Median radiation dose was 50.4 Gy.more » The location of all celiac node failures was compared with the radiation treatment plan to determine whether the failures occurred within or outside the radiation treatment field. Results: At a median follow-up time of 52.6 months (95% CI 46.1-56.7 months), 6 of 60 patients (10%) without celiac node coverage had celiac nodal failure; in 5 of these patients, the failures represented the first site of recurrence. Of the 71 patients who had celiac coverage, only 5 patients (7%) had celiac region relapse. In multivariate analyses, having a pretreatment-to-post-treatment change in standardized uptake value on PET >52% (odds ratio [OR] 0.198, p = 0.0327) and having failure in the clinical target volume (OR 10.72, p = 0.001) were associated with risk of celiac region relapse. Of those without celiac coverage, the 6 patients that later developed celiac failure had a worse median overall survival time compared with the other 54 patients who did not fail (median overall survival time: 16.5 months vs. 31.5 months, p = 0.041). Acute and late toxicities were similar in both groups. Conclusions: Although celiac lymph node failures occur in approximately 1 of 10 patients, the lack of effective salvage treatments and subsequent low morbidity may justify prophylactic

  20. Radical Radiation Therapy After Lung-Sparing Surgery for Malignant Pleural Mesothelioma: Survival, Pattern of Failure, and Prognostic Factors

    SciTech Connect

    Minatel, Emilio; Trovo, Marco, E-mail: marcotrovo33@hotmail.com; Bearz, Alessandra

    Purpose: To prospectively assess the survival, patterns of failure, and prognostic factors in a large cohort of patients with malignant pleural mesothelioma who had undergone a novel trimodal therapeutic approach, including lung-sparing surgery, chemotherapy, and subsequent treatment with high doses of intensity modulated radiation therapy (IMRT) to the whole hemithorax. Methods and Materials: The analysis was conducted on the data from 69 patients. Of the 69 patients, 35 underwent extended pleurectomy/decortication (P/D), with resection of the entire pleura, along with portions of the pericardium and diaphragm and 34, partial pleurectomy, defined as partial removal of parietal or visceral pleura formore » diagnostic purposes, leaving gross tumor behind in all cases. All patients received cisplatin/pemetrexed chemotherapy. Postoperative IMRT was delivered to the entire hemithorax, excluding the intact lung. The IMRT dose was 50 Gy in 25 fractions. Any fluorodeoxyglucose-avid areas or regions of particular concern for residual disease were given a simultaneous boost to 60 Gy. Results: The median follow-up duration was 19 months. No difference was seen in overall survival and locoregional control between the extended P/D group and the partial pleurectomy group. The 2-year overall survival was 65% and 58% in the extended P/D and partial pleurectomy groups, respectively (P=.94). Locoregional control at 2 years was 65% and 64% in the extended P/D and partial pleurectomy groups, respectively (P=.75). The predominant pattern of failure was distant: 19 patients (27.5%) developed distant metastases as the first site of relapse. Gross residual disease after surgery was significantly associated with overall survival (hazard ratio 3.45). One fatal pneumonitis was reported; 14 cases (20%) of grade 2 to 3 pneumonitis were documented. Conclusions: Radical IMRT after lung-sparing surgery and chemotherapy for malignant pleural mesothelioma leads to promising survival results

  1. [Brain oedema and acute liver failure].

    PubMed

    Spahr, L

    2003-04-01

    Brain oedema leading to intracranial hypertension occurs in a significant proportion of patients with acute liver failure in whom it is a leading cause of death. Although precise pathogenic mechanisms associated to this severe complication remain incompletely understood, increasing evidence points to gut-derived neurotoxins including ammonia as key mediators in cerebral osmotic and perfusion disturbances. The management of brain oedema and intracranial hypertension requires a multidisciplinar approach in a center where liver transplantation is available, as this option is the only treatment modality that provides improvement in outcome. This article reviews the most common causes of acute liver failure and the standard of supportive care management, and describes future potential therapeutic aspects of brain oedema and intracranial hypertension.

  2. Acute Liver Failure including Acetaminophen Overdose

    PubMed Central

    Fontana, Robert J.

    2008-01-01

    Synopsis Acute liver failure (ALF) is a dramatic and highly unpredictable clinical syndrome defined by the sudden onset of coagulopathy and encephalopathy. Although many disease processes can cause ALF, acetaminophen overdose is the leading cause in the United States, and has a 66% chance of recovery with early N-acetylcysteine treatment and supportive care. Cerebral edema and infectious complications are notoriously difficult to detect and treat in ALF patients and may lead to irreversible brain damage and multi-organ failure. Emergency liver transplantation is associated with a 70% 1-year patient survival but 20% of listed patients die, highlighting the importance of early referral of ALF patients with a poor prognosis to a liver transplant center. PMID:18570942

  3. Chagas disease as a cause of heart failure and ventricular arrhythmias in patients long removed from endemic areas: an emerging problem in Europe.

    PubMed

    Vannucchi, Vieri; Tomberli, Benedetta; Zammarchi, Lorenzo; Fornaro, Alessandra; Castelli, Gabriele; Pieralli, Filippo; Berni, Andrea; Yacoub, Sophie; Bartoloni, Alessandro; Olivotto, Iacopo

    2015-12-01

    Chagas disease is a parasitic disease caused by the protozoan Trypanosoma cruzi. In endemic areas (South and Central America), Chagas disease represents a relevant public health issue, and is the most frequent cause of cardiomyopathy. In nonendemic areas, such as Europe, Chagas disease represents an emerging problem following the establishment of sizeable communities from Brazil and Bolivia. Chagas cardiomyopathy represents the most frequent and serious complication of chronic Chagas disease, affecting about 20-30% of patients, potentially leading to heart failure, arrhythmias, thromboembolism, stroke and sudden death. Because late complications of Chagas disease may develop several years or even decades after the acute infection, it may be extremely challenging to reach the correct diagnosis in patients long removed from the countries of origin. We report two examples of Chagas cardiomyopathy in South American women permanently residing in Italy for more than 20 years, presenting with cardiac manifestations ranging from left ventricular dysfunction and heart failure to isolated ventricular arrhythmias. The present review emphasizes that Chagas disease should be considered as a potential diagnosis in patients from endemic areas presenting with 'idiopathic' cardiac manifestations, even when long removed from their country of origin, with potential implications for treatment and control of Chagas disease transmission.

  4. Epidemiology of central sleep apnoea in heart failure.

    PubMed

    Naughton, Matthew T

    2016-03-01

    Central sleep apnoea occurs in about a third of patients with reduced systolic heart failure and is a marker of increased mortality. Such patients usually are older males with advanced heart failure (i.e., high pulmonary wedge pressure), often in atrial fibrillation, with evidence of hyperventilation (i.e., low PaCO2) in the absence of hypoxemia. Characteristically, ventilation waxes and wanes in a sinusoidal pattern, with mild hypoxemia, occurring in the lighter levels of sleep usually when supine. Snoring may also occur in central sleep apnoea, often at the peak of hyperventilation, sometimes contributing to the confusion or overlap with obstructive sleep apnoea. Central sleep apnoea is associated with orthopnoea, paroxysmal nocturnal dyspnoea and an oscillatory respiratory pattern with an incremental cardiopulmonary exercise study. Importantly, heart failure therapies (e.g., afterload reduction, diuresis, pacemakers, transplantation) attenuate central sleep apnoea. Night to night variability in severity of central sleep apnoea may occur with changes in patients' posture during sleep (less severe when sleeping on-side or upright). Crown Copyright © 2016. Published by Elsevier Ireland Ltd. All rights reserved.

  5. The Role of Academic Failure in Hyperactive Behavior

    ERIC Educational Resources Information Center

    Cunningham, Charles E.; Barkley, Russell A.

    1978-01-01

    A model and supporting research are presented which suggest that academic failure resulting from a variety of etiological factors is sufficient to generate the behavioral patterns observed in many hyperactive children. (CL)

  6. Pharmacological management of chronic heart failure in adults: a review of the literature.

    PubMed

    Auty, Richard

    2004-03-01

    Heart failure is a common, life threatening condition encountered in patients of all ages and in all clinical settings. It may be due to any of a wide variety of causes - in Malawi, cardiomyopathies, hypertension and rheumatic heart disease are probably the commonest causes of heart failure. In more affluent societies, ischaemic heart disease is an important factor. Chronic heart failure (CHF) causes significant morbidity: it reduces exercise capacity, interferes with sleep and produces unsightly and uncomfortable oedema. The syndrome also carries substantial mortatity, worse than that of many malignant tumours: 20 -30% of patients with mild or moderately severe heart failure will die every year if left untreated. The life expectancy of a patient with untreated severe heart failure is only about 6 months. Table 1 explains the symptomatic classification of the severity of heart failure. Objective measurements of cardiac function, such as Left Ventricular Ejection Fraction (LYEF) or chamber filling pressures, correlate poorly with symptoms and New York Heart Association (NYHA) classification. Many of the problems experienced by a patient with heart failure are due to a 'vicious circle' of events in which pathophysiological responses to the falling cardiac output cause further deterioration in cardiac function over time. These responses include ventricular remodeling, neurohumoural activation (increased sympathetic activity; increased atrial natriuretic peptide; increased angiotensin II), increased activity of the renin-angiotensin-aldosterone system (RAAS) causing fluid retention, vasoconstriction and sodium retention. [Table: see text].

  7. Metallization failures

    NASA Technical Reports Server (NTRS)

    Beatty, R.

    1971-01-01

    Metallization-related failure mechanisms were shown to be a major cause of integrated circuit failures under accelerated stress conditions, as well as in actual use under field operation. The integrated circuit industry is aware of the problem and is attempting to solve it in one of two ways: (1) better understanding of the aluminum system, which is the most widely used metallization material for silicon integrated circuits both as a single level and multilevel metallization, or (2) evaluating alternative metal systems. Aluminum metallization offers many advantages, but also has limitations particularly at elevated temperatures and high current densities. As an alternative, multilayer systems of the general form, silicon device-metal-inorganic insulator-metal, are being considered to produce large scale integrated arrays. The merits and restrictions of metallization systems in current usage and systems under development are defined.

  8. Patterns and predictors of patient and caregiver engagement in heart failure care: a multi-level dyadic study.

    PubMed

    Lee, Christopher S; Vellone, Ercole; Lyons, Karen S; Cocchieri, Antonello; Bidwell, Julie T; D'Agostino, Fabio; Hiatt, Shirin O; Alvaro, Rosaria; Buck, Harleah G; Riegel, Barbara

    2015-02-01

    Heart failure is a burdensome clinical syndrome, and patients and their caregivers are responsible for the vast majority of heart failure care. This study aimed to characterize naturally occurring archetypes of patient-caregiver dyads with respect to patient and caregiver contributions to heart failure self-care, and to identify patient-, caregiver- and dyadic-level determinants thereof. Dyadic analysis of cross-sectional data on patients and their caregivers. Outpatient heart failure clinics in 28 Italian provinces. 509 Italian heart failure patients and their primary caregivers. Multilevel and mixture modeling were used to generate dyadic averages and incongruence in patient and caregiver contributions to heart failure self-care and identify common dyadic archetypes, respectively. Three distinct archetypes were observed. 22.4% of dyads were labeled as novice and complementary because patients and caregivers contributed to different aspects of heart failure self-care that was generally poor; these dyads were predominantly older adults with less severe heart failure and their adult child caregivers. 56.4% of dyads were labeled as inconsistent and compensatory because caregivers reported greater contributions to the areas of self-care most insufficient on the part of the patients; patients in these dyads had the highest prevalence of hospitalizations for heart failure in the past year and the fewest limitations to performing activities of daily living independently. Finally, 21.2% of dyads were labeled as expert and collaborative because of high contributions to all aspects of heart failure self-care, the best relationship quality and lowest caregiver strain compared with the other archetypes; patients in this archetype were likely the sickest because they also had the worst heart failure-related quality of life. Three distinct archetypes of dyadic contributions to heart failure care were observed that represent a gradient in the level of contributions to self

  9. A Mid-Layer Model for Human Reliability Analysis: Understanding the Cognitive Causes of Human Failure Events

    SciTech Connect

    Stacey M. L. Hendrickson; April M. Whaley; Ronald L. Boring

    The Office of Nuclear Regulatory Research (RES) is sponsoring work in response to a Staff Requirements Memorandum (SRM) directing an effort to establish a single human reliability analysis (HRA) method for the agency or guidance for the use of multiple methods. As part of this effort an attempt to develop a comprehensive HRA qualitative approach is being pursued. This paper presents a draft of the method’s middle layer, a part of the qualitative analysis phase that links failure mechanisms to performance shaping factors. Starting with a Crew Response Tree (CRT) that has identified human failure events, analysts identify potential failuremore » mechanisms using the mid-layer model. The mid-layer model presented in this paper traces the identification of the failure mechanisms using the Information-Diagnosis/Decision-Action (IDA) model and cognitive models from the psychological literature. Each failure mechanism is grouped according to a phase of IDA. Under each phase of IDA, the cognitive models help identify the relevant performance shaping factors for the failure mechanism. The use of IDA and cognitive models can be traced through fault trees, which provide a detailed complement to the CRT.« less

  10. East Coast Fever Caused by Theileria parva Is Characterized by Macrophage Activation Associated with Vasculitis and Respiratory Failure

    PubMed Central

    Schneider, David A.; Frevert, Charles W.; Nelson, Danielle D.; Morrison, W. Ivan; Knowles, Donald P.

    2016-01-01

    Respiratory failure and death in East Coast Fever (ECF), a clinical syndrome of African cattle caused by the apicomplexan parasite Theileria parva, has historically been attributed to pulmonary infiltration by infected lymphocytes. However, immunohistochemical staining of tissue from T. parva infected cattle revealed large numbers of CD3- and CD20-negative intralesional mononuclear cells. Due to this finding, we hypothesized that macrophages play an important role in Theileria parva disease pathogenesis. Data presented here demonstrates that terminal ECF in both Holstein and Boran cattle is largely due to multisystemic histiocytic responses and resultant tissue damage. Furthermore, the combination of these histologic changes with the clinical findings, including lymphadenopathy, prolonged pyrexia, multi-lineage leukopenia, and thrombocytopenia is consistent with macrophage activation syndrome. All animals that succumbed to infection exhibited lymphohistiocytic vasculitis of small to medium caliber blood and lymphatic vessels. In pulmonary, lymphoid, splenic and hepatic tissues from Holstein cattle, the majority of intralesional macrophages were positive for CD163, and often expressed large amounts of IL-17. These data define a terminal ECF pathogenesis in which parasite-driven lymphoproliferation leads to secondary systemic macrophage activation syndrome, mononuclear vasculitis, pulmonary edema, respiratory failure and death. The accompanying macrophage phenotype defined by CD163 and IL-17 is presented in the context of this pathogenesis. PMID:27195791

  11. Acute Heart Failure Management

    PubMed Central

    2018-01-01

    Acute heart failure (AHF) is a life-threatening medical condition, where urgent diagnostic and treatment methods are of key importance. However, there are few evidence-based treatment methods. Interestingly, despite relatively similar ways of management of AHF throughout the globe, mid-term outcome in East Asia, including South Korea is more favorable than in Europe. Yet, most of the treatment methods are symptomatic. The cornerstone of AHF management is identifying precipitating factors and specific phenotype. Multidisciplinary approach is important in AHF, which can be caused or aggravated by both cardiac and non-cardiac causes. The main pathophysiological mechanism in AHF is congestion, both systemic and inside the organs (lung, kidney, or liver). Cardiac output is often preserved in AHF except in a few cases of advanced heart failure. This paper provides guidance on AHF management in a time-based approach. Treatment strategies, criteria for triage, admission to hospital and discharge are described. PMID:29856141

  12. Failure mechanisms of single-crystal silicon electrodes in lithium-ion batteries

    PubMed Central

    Shi, Feifei; Song, Zhichao; Ross, Philip N.; Somorjai, Gabor A.; Ritchie, Robert O.; Komvopoulos, Kyriakos

    2016-01-01

    Long-term durability is a major obstacle limiting the widespread use of lithium-ion batteries in heavy-duty applications and others demanding extended lifetime. As one of the root causes of the degradation of battery performance, the electrode failure mechanisms are still unknown. In this paper, we reveal the fundamental fracture mechanisms of single-crystal silicon electrodes over extended lithiation/delithiation cycles, using electrochemical testing, microstructure characterization, fracture mechanics and finite element analysis. Anisotropic lithium invasion causes crack initiation perpendicular to the electrode surface, followed by growth through the electrode thickness. The low fracture energy of the lithiated/unlithiated silicon interface provides a weak microstructural path for crack deflection, accounting for the crack patterns and delamination observed after repeated cycling. On the basis of this physical understanding, we demonstrate how electrolyte additives can heal electrode cracks and provide strategies to enhance the fracture resistance in future lithium-ion batteries from surface chemical, electrochemical and material science perspectives. PMID:27297565

  13. Failure mechanisms of single-crystal silicon electrodes in lithium-ion batteries

    DOE PAGES

    Shi, Feifei; Song, Zhichao; Ross, Philip N.; ...

    2016-06-14

    Long-term durability is a major obstacle limiting the widespread use of lithium-ion batteries in heavy-duty applications and others demanding extended lifetime. As one of the root causes of the degradation of battery performance, the electrode failure mechanisms are still unknown. In this paper, we reveal the fundamental fracture mechanisms of single-crystal silicon electrodes over extended lithiation/delithiation cycles, using electrochemical testing, microstructure characterization, fracture mechanics and finite element analysis. Anisotropic lithium invasion causes crack initiation perpendicular to the electrode surface, followed by growth through the electrode thickness. The low fracture energy of the lithiated/unlithiated silicon interface provides a weak microstructural pathmore » for crack deflection, accounting for the crack patterns and delamination observed after repeated cycling. On the basis of this physical understanding, we demonstrate how electrolyte additives can heal electrode cracks and provide strategies to enhance the fracture resistance in future lithium-ion batteries from surface chemical, electrochemical and material science perspectives.« less

  14. Failure mechanisms of single-crystal silicon electrodes in lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Shi, Feifei; Song, Zhichao; Ross, Philip N.; Somorjai, Gabor A.; Ritchie, Robert O.; Komvopoulos, Kyriakos

    2016-06-01

    Long-term durability is a major obstacle limiting the widespread use of lithium-ion batteries in heavy-duty applications and others demanding extended lifetime. As one of the root causes of the degradation of battery performance, the electrode failure mechanisms are still unknown. In this paper, we reveal the fundamental fracture mechanisms of single-crystal silicon electrodes over extended lithiation/delithiation cycles, using electrochemical testing, microstructure characterization, fracture mechanics and finite element analysis. Anisotropic lithium invasion causes crack initiation perpendicular to the electrode surface, followed by growth through the electrode thickness. The low fracture energy of the lithiated/unlithiated silicon interface provides a weak microstructural path for crack deflection, accounting for the crack patterns and delamination observed after repeated cycling. On the basis of this physical understanding, we demonstrate how electrolyte additives can heal electrode cracks and provide strategies to enhance the fracture resistance in future lithium-ion batteries from surface chemical, electrochemical and material science perspectives.

  15. Failure is an option: Reactions to failure in elementary engineering design projects

    NASA Astrophysics Data System (ADS)

    Johnson, Matthew M.

    Recent reform documents in science education have called for teachers to use epistemic practices of science and engineering researchers to teach disciplinary content (NRC, 2007; NRC, 2012; NGSS Lead States, 2013). Although this creates challenges for classroom teachers unfamiliar with engineering, it has created a need for high quality research about how students and teachers engage in engineering activities to improve curriculum development and teaching pedagogy. While framers of the Next Generation Science Standards (NRC, 2012; NGSS Lead States 2013) focused on the similarities of the practices of science researchers and engineering designers, some have proposed that engineering has a unique set of epistemic practices, including improving from failure (Cunningham & Carlsen, 2014; Cunningham & Kelly, in review). While no one will deny failures occur in science, failure in engineering is thought of in fundamentally different ways. In the study presented here, video data from eight classes of elementary students engaged in one of two civil engineering units were analyzed using methods borrowed from psychology, anthropology, and sociolinguistics to investigate: 1) the nature of failure in elementary engineering design; 2) the ways in which teachers react to failure; and 3) how the collective actions of students and teachers support or constrain improvement in engineering design. I propose new ways of considering the types and causes of failure, and note three teacher reactions to failure: the manager, the cheerleader, and the strategic partner. Because the goal of iteration in engineering is improvement, I also studied improvement. Students only systematically improve when they have the opportunity, productive strategies, and fair comparisons between prototypes. I then investigate the use of student engineering journals to assess learning from the process of improvement after failure. After discussion, I consider implications from this work as well as future research

  16. The pathophysiology of heart failure.

    PubMed

    Kemp, Clinton D; Conte, John V

    2012-01-01

    Heart failure is a clinical syndrome that results when the heart is unable to provide sufficient blood flow to meet metabolic requirements or accommodate systemic venous return. This common condition affects over 5 million people in the United States at a cost of $10-38 billion per year. Heart failure results from injury to the myocardium from a variety of causes including ischemic heart disease, hypertension, and diabetes. Less common etiologies include cardiomyopathies, valvular disease, myocarditis, infections, systemic toxins, and cardiotoxic drugs. As the heart fails, patients develop symptoms which include dyspnea from pulmonary congestion, and peripheral edema and ascites from impaired venous return. Constitutional symptoms such as nausea, lack of appetite, and fatigue are also common. There are several compensatory mechanisms that occur as the failing heart attempts to maintain adequate function. These include increasing cardiac output via the Frank-Starling mechanism, increasing ventricular volume and wall thickness through ventricular remodeling, and maintaining tissue perfusion with augmented mean arterial pressure through activation of neurohormonal systems. Although initially beneficial in the early stages of heart failure, all of these compensatory mechanisms eventually lead to a vicious cycle of worsening heart failure. Treatment strategies have been developed based upon the understanding of these compensatory mechanisms. Medical therapy includes diuresis, suppression of the overactive neurohormonal systems, and augmentation of contractility. Surgical options include ventricular resynchronization therapy, surgical ventricular remodeling, ventricular assist device implantation, and heart transplantation. Despite significant understanding of the underlying pathophysiological mechanisms in heart failure, this disease causes significant morbidity and carries a 50% 5-year mortality. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. [Epidemiology of severe acute renal failure in Metropolitan Santiago].

    PubMed

    Vukusich, Antonio; Alvear, Felipe; Villanueva, Pablo; González, Claudio; Francisco, Olivari; Alvarado, Nelly; Zehnder, Carlos

    2004-11-01

    There is a paucity of information about the epidemiology of acute renal failure in Chile. To perform a prospective multicentric survey of severe acute renal failure in Chile. All patients admitted to ten hospitals in Metropolitan Santiago, during a period of six months with severe acute renal failure, were studied. The criteria for severity was the requirement of renal replacement therapy. All patients information was gathered in special forms and the type of renal replacement therapy and evolution was registeres. One hundred fourteen patients were studied (65 males, age range 18 to 87 years). The calculated incidence of acute renal failure was 1.03 cases per 1000 hospital discharges. The onset was nosocomial in 79 subjects (69%) and community acquired in the rest. Renal failure was oliguric in 64 cases (56%) and in 60% of patients it had two or more causative factors. Sepsis, isolated or combined with other causes, was present in 51 of patients. Other causes included ischemia in 47%, surgery in 26%, exogenous toxicity in 25%, endocenous toxicity in 11%, acute glomerular damage in 6% and obstructive uropathy in 6%. Cardiac surgery was responsible for 47% of post operative cases of acute renal failure. Intermittent conventional hemodialysis, continuous renal replacement techniques and daily prolonged hemodialysis were used in 66%, 29% and 2% of patients, respectively. Overall mortality was 45% and it was higher in oliguric patients. Gender, age, cause or the type of therapy did not influence survival. Nine percent of surviving patients had some degree of kidney dysfunction at discharge. There is still a great space for prevention of severe acute renal failure in Chile, considering the main etiologies found in this study.

  18. Application of multi attribute failure mode analysis of milk production using analytical hierarchy process method

    NASA Astrophysics Data System (ADS)

    Rucitra, A. L.

    2018-03-01

    Pusat Koperasi Induk Susu (PKIS) Sekar Tanjung, East Java is one of the modern dairy industries producing Ultra High Temperature (UHT) milk. A problem that often occurs in the production process in PKIS Sekar Tanjung is a mismatch between the production process and the predetermined standard. The purpose of applying Analytical Hierarchy Process (AHP) was to identify the most potential cause of failure in the milk production process. Multi Attribute Failure Mode Analysis (MAFMA) method was used to eliminate or reduce the possibility of failure when viewed from the failure causes. This method integrates the severity, occurrence, detection, and expected cost criteria obtained from depth interview with the head of the production department as an expert. The AHP approach was used to formulate the priority ranking of the cause of failure in the milk production process. At level 1, the severity has the highest weight of 0.41 or 41% compared to other criteria. While at level 2, identifying failure in the UHT milk production process, the most potential cause was the average mixing temperature of more than 70 °C which was higher than the standard temperature (≤70 ° C). This failure cause has a contributes weight of 0.47 or 47% of all criteria Therefore, this study suggested the company to control the mixing temperature to minimise or eliminate the failure in this process.

  19. Yogi Detox Tea: A Potential Cause of Acute Liver Failure.

    PubMed

    Kesavarapu, Keerthana; Kang, Mitchell; Shin, Jaewook James; Rothstein, Kenneth

    2017-01-01

    We present a case of acute fulminant liver failure from a liver detoxification tea. We present a 60-year-old female with weakness, lethargy, scleral icterus, jaundice, and worsening mental status. She drank herbal tea three times a day for 14 days prior to symptom development. Liver tests were elevated. Remaining laboratory tests and imaging were negative for other etiologies. An ultrasound-guided liver biopsy showed submassive necrosis. A literature search on the ingredients shows six ingredients as having hepatotoxic effects and remaining ingredients as having very sparse hepatoprotective data. Healthcare professionals should discuss herbal medication and tea use and report adverse effects.

  20. Prediction of mode of death in heart failure: the Seattle Heart Failure Model.

    PubMed

    Mozaffarian, Dariush; Anker, Stefan D; Anand, Inder; Linker, David T; Sullivan, Mark D; Cleland, John G F; Carson, Peter E; Maggioni, Aldo P; Mann, Douglas L; Pitt, Bertram; Poole-Wilson, Philip A; Levy, Wayne C

    2007-07-24

    Prognosis and mode of death in heart failure patients are highly variable in that some patients die suddenly (often from ventricular arrhythmia) and others die of progressive failure of cardiac function (pump failure). Prediction of mode of death may facilitate decisions about specific medications or devices. We used the Seattle Heart Failure Model (SHFM), a validated prediction model for total mortality in heart failure, to assess the mode of death in 10,538 ambulatory patients with New York Heart Association class II to IV heart failure and predominantly systolic dysfunction enrolled in 6 randomized trials or registries. During 16,735 person-years of follow-up, 2014 deaths occurred, which included 1014 sudden deaths and 684 pump-failure deaths. Compared with a SHFM score of 0, patients with a score of 1 had a 50% higher risk of sudden death, patients with a score of 2 had a nearly 3-fold higher risk, and patients with a score of 3 or 4 had a nearly 7-fold higher risk (P<0.001 for all comparisons; 1-year area under the receiver operating curve, 0.68). Stratification of risk of pump-failure death was even more pronounced, with a 4-fold higher risk with a score of 1, a 15-fold higher risk with a score of 2, a 38-fold higher risk with a score of 3, and an 88-fold higher risk with a score of 4 (P<0.001 for all comparisons; 1-year area under the receiver operating curve, 0.85). The proportion of deaths caused by sudden death versus pump-failure death decreased from a ratio of 7:1 with a SHFM score of 0 to a ratio of 1:2 with a SHFM score of 4 (P trend <0.001). The SHFM score provides information about the likely mode of death among ambulatory heart failure patients. Investigation is warranted to determine whether such information might predict responses to or cost-effectiveness of specific medications or devices in heart failure patients.

  1. Zebrafish heart failure models: opportunities and challenges.

    PubMed

    Shi, Xingjuan; Chen, Ru; Zhang, Yu; Yun, Junghwa; Brand-Arzamendi, Koroboshka; Liu, Xiangdong; Wen, Xiao-Yan

    2018-05-03

    Heart failure is a complex pathophysiological syndrome of pumping functional failure that results from injury, infection or toxin-induced damage on the myocardium, as well as genetic influence. Gene mutations associated with cardiomyopathies can lead to various pathologies of heart failure. In recent years, zebrafish, Danio rerio, has emerged as an excellent model to study human cardiovascular diseases such as congenital heart defects, cardiomyopathy, and preclinical development of drugs targeting these diseases. In this review, we will first summarize zebrafish genetic models of heart failure arose from cardiomyopathy, which is caused by mutations in sarcomere, calcium or mitochondrial-associated genes. Moreover, we outline zebrafish heart failure models triggered by chemical compounds. Elucidation of these models will improve the understanding of the mechanism of pathogenesis and provide potential targets for novel therapies.

  2. Controls on radon emission from granite as evidenced by compression testing to failure

    NASA Astrophysics Data System (ADS)

    Koike, Katsuaki; Yoshinaga, Tohru; Suetsugu, Kenta; Kashiwaya, Koki; Asaue, Hisafumi

    2015-10-01

    A set of uniaxial compression tests of granite specimens taken from five localities across Japan was conducted to identify the factors controlling the quantity of radon (Rn) emission (sum of 222Rn and 220Rn) during compression and failure. An α-scintillation detector and a gas flow unit were installed with a testing machine to enable continuous measurement of Rn emissions. Common to all specimens, Rn emissions remained at or slightly declined from the background level after the start of loading; this is similar to the natural phenomenon of decline in groundwater-dissolved Rn before an earthquake. Closure of original microcracks is the most likely cause of the initial Rn decline. Then, Rn emissions begin to increase at 46-57 per cent stress level to the uniaxial compressive strength, and continue to increase even after the failure of specimen. This commencement stress level is close to the general stress level at outbreak of acoustic emissions caused by the development and connection of microcracks. The Rn increase after failure is similar to a phenomenon observed in aftershocks, which may originate from the enhancement of Rn emanations from grains due to the large increase in total surface area and stress release. In addition to the initial radioelement content in rock, the failure pattern (conjugate shear versus longitudinal tensile type), compressive strength, and grain size are possible control factors of the maximum quantity of Rn emissions induced by failure. This maximum may also be affected by the development velocity of the emanation area, which is related to the Rn emanation fraction, associated with the fragmentation. In addition to the magnitude of an earthquake and its hypocentre distance to Rn detectors, the magnitude of increase in Rn concentration in soil gas and groundwater before, during, and after an earthquake in crystalline rocks depends on the intrinsic radioelement content, the mineral texture, and the mechanical properties of rocks. Rock

  3. Constructing Failure: Leonard Hayflick, Biomedicine, and the Problems with Tissue Culture.

    PubMed

    Park, Hyung Wook

    2016-07-01

    By examining the use of tissue culture in post-war American biomedicine, this paper investigates how scientists experience and manage failure. I study how Leonard Hayflick forged his new definition of failure and ways of managing it by refuting Alexis Carrel's definition of failure alongside his theory of the immortality of cultured cells. Unlike Carrel, Hayflick claimed that every vertebrate somatic cell should eventually die, unless it transformed into a tumour cell. This claim defined cell death, which had been a problem leading to a laboratory failure, as a normal phenomenon. On the other hand, permanent life, which had been considered a normal cellular characteristic, became a major factor causing scientific failure, since it implied malignant transformation that scientists hoped to control. Hayflick then asserted that his cell strains and method would partly enable scientists to manage this factor-especially that occurred through viral infection-alongside other causes of failure in routine tasks, including bacterial contamination. I argue that the growing biomedical enterprise fostered this work of Hayflick's, which had repercussions in both his career and the uses of cells in diverse investigations. His redefinition of failure in the age of biomedicine resulted in the broad dissemination of his cells, medium, and method as well as his long struggle with the National Institutes of Health (NIH), which caused his temporarily failed career.

  4. Panhypopituitarism presenting as life-threatening heart failure caused by an inherited microdeletion in 1q25 including LHX4.

    PubMed

    Filges, Isabel; Bischof-Renner, Andrea; Röthlisberger, Benno; Potthoff, Christian; Glanzmann, René; Günthard, Joëlle; Schneider, Jacques; Huber, Andreas R; Zumsteg, Urs; Miny, Peter; Szinnai, Gabor

    2012-02-01

    Clinical presentation of hypopituitarism in the neonate may be variable, ranging from absent to severe nonspecific symptoms and may be life-threatening in patients with adrenocorticotropic hormone deficiency. The LIM homeobox gene 4 (LHX4) transcription factor regulates early embryonic development of the anterior pituitary gland. Autosomal dominant mutations in LHX4 cause congenital hypopituitarism with variable combined pituitary hormone deficiency (CPHD). We report on a neonate with unexplained heart failure and minor physical anomalies, suggesting a midline defect. She was diagnosed with complete CPHD. Cardiac function was rescued by replacement with hydrocortisone and thyroxine; hypoglycaemia stopped under growth hormone therapy. Magnetic resonance imaging revealed a dysgenetic pituitary gland suggesting an early developmental defect. Array comparative genomic hybridization showed a maternally inherited 1.5-megabase microdeletion in 1q25.2q25.3, including the LHX4 gene. Haploinsufficiency of LHX4 likely explains the predominant pituitary phenotype in the proposita and we suggest variable intrafamilial penetrance of the inherited microdeletion. To the best of our knowledge, we are the first to report on heart failure as a rare nonspecific symptom of treatable CPHD in the newborn. Variably penetrant pituitary insufficiency, including this severe and atypical presentation, can be correlated with LHX4 insufficiency and highlights the role of LHX4 for pituitary development.

  5. Usefulness of Medical Thoracoscopy in the Management of Pleural Effusion Caused by Chronic Renal Failure.

    PubMed

    Colella, Sara; Fioretti, Federica; Massaccesi, Chiara; Primomo, Gian L; Panella, Gianluca; D'Emilio, Vittorio; Pela, Riccardo

    2017-10-01

    Although pleural effusion (PE) can be caused by several pathologies like congestive heart failure, infections, malignancies, and pulmonary embolism, it is also a common finding in chronic kidney disease (CKD). Diagnostic thoracentesis is of limited value in the differential diagnosis, and the role of more invasive investigations like medical thoracoscopy (MT) is still unclear. To evaluate the usefulness of MT in unexplained PE in CKD. In the electronic database of our Institution, we retrospectively searched for patients with CKD who underwent MT for unexplained PE between January 2008 and August 2016. Ten patients were included in the present study. The average age was 72.4 years, the male:female ratio 9:1 and the average blood creatinine value 5.96 mg/dL. The average follow-up was 18 months.A thoracentesis showed an exudate was found in 9 patients and in 1 case pleural fluid characteristics were not recorded for technical reasons; in none of them the cytologic or microbiological analyses were considered diagnostic.The clinical suspicion was a neoplastic (5) or an infectious disease (5). In 4 patients with recurrent PE, MT was performed to obtain talc pleurodesis.No immediate procedure-related complications were recorded; 1 patient developed empyema after 2 months. In 6 cases final diagnosis was chronic uremic pleuritis, hydrothorax in 2, and chronic lymphocytic pleurisy in 2. MT represents a safe and effective diagnostic and therapeutic procedure in patients with CKD, that itself is a common cause of exudative effusion, and those patients may not require MT.

  6. miR-21 is associated with fibrosis and right ventricular failure

    PubMed Central

    Hu, Dong-Qing; Zhao, Mingming; Blay, Eddie; Sandeep, Nefthi; Ong, Sang-Ging; Jung, Gwanghyun; Kooiker, Kristina B.; Coronado, Michael; Fajardo, Giovanni; Bernstein, Daniel

    2017-01-01

    Combined pulmonary insufficiency (PI) and stenosis (PS) is a common long-term sequela after repair of many forms of congenital heart disease, causing progressive right ventricular (RV) dilation and failure. Little is known of the mechanisms underlying this combination of preload and afterload stressors. We developed a murine model of PI and PS (PI+PS) to identify clinically relevant pathways and biomarkers of disease progression. Diastolic dysfunction was induced (restrictive RV filling, elevated RV end-diastolic pressures) at 1 month after generation of PI+PS and progressed to systolic dysfunction (decreased RV shortening) by 3 months. RV fibrosis progressed from 1 month (4.4% ± 0.4%) to 3 months (9.2% ± 1%), along with TGF-β signaling and tissue expression of profibrotic miR-21. Although plasma miR-21 was upregulated with diastolic dysfunction, it was downregulated with the onset of systolic dysfunction), correlating with RV fibrosis. Plasma miR-21 in children with PI+PS followed a similar pattern. A model of combined RV volume and pressure overload recapitulates the evolution of RV failure unique to patients with prior RV outflow tract surgery. This progression was characterized by enhanced TGF-β and miR-21 signaling. miR-21 may serve as a plasma biomarker of RV failure, with decreased expression heralding the need for valve replacement. PMID:28469078

  7. Causes of organ donation failure in Brazil.

    PubMed

    Dell Agnolo, C M; de Freitas, R A; Toffolo, V J O; de Oliveira, M L F; de Almeida, D F; Carvalho, M D B; Pelloso, S M

    2012-10-01

    There has been a great improvement in transplantation medicine in Brazil in the last 2 decades. However, there remain several barriers regarding notification of brain and cardiac death as well as completion of the donation process. This retrospective study was performed between January 2008 and December 2010. We reviewed all deaths in a University Hospital, observing the causes of non-notification to the State Transplantation Authority and non-donations. There were 41 notifications of brain death resulting in donation in only 19.5% of those cases. Cardiac death was diagnosed in 21 patients, resulting in 52.4% donations. The main cause for non-donation were family refusal (37.2%), infectious diseases (30.2%), and clinical contraindications (32.6%). Most of the missed possible donors occurred during the night (54.8%) and in the emergency room (80.9%). There is an urgent need for better education of the Brazilian population about organ donation and brain death definitions. Other identified problems include lack of uniformity in brain death determinations among hospitals, rigid contraindications to donation in the State of Parana, physician unawareness or disbelief about brain death diagnostic criteria, and lack of structure of our Hospital. Copyright © 2012. Published by Elsevier Inc.

  8. Performance Concern, Contingent Self-Worth, and Responses to Repeated Achievement Failure in Second Graders

    ERIC Educational Resources Information Center

    Smiley, Patricia A.; Coulson, Sheri L.; Greene, Joelle K.; Bono, Katherine L.

    2010-01-01

    Individual differences in emotion, cognitions, and task choice following achievement failure are found among four- to seven-year-olds. However, neither performance deterioration during failure nor generalization after failure--aspects of the helpless pattern in 10-year-olds--have been reliably demonstrated in this age group. In the present study,…

  9. Asymmetrical booster guidance and control system design study. Volume 3: Space shuttle vehicle SRB actuator failure study. [space shuttle development

    NASA Technical Reports Server (NTRS)

    Williams, F. E.; Lemon, R. S.

    1974-01-01

    The investigation of single actuator failures on the space shuttle solid rocket booster required the analysis of both square pattern and diamond pattern actuator configurations. It was determined that for failures occuring near or prior to the region of maximum dynamic pressure, control gain adjustments can be used to achieve virtually nominal mid-boost vehicle behavior. A distinct worst case failure condition was established near staging that could significantly delay staging. It is recommended that the square pattern be retained as a viable alternative to the baseline diamond pattern because the staging transient is better controlled resulting in earlier staging.

  10. Satellite failures revisited

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2012-12-01

    In January 1994, the two geostationary satellites known as Anik-E1 and Anik-E2, operated by Telesat Canada, failed one after the other within 9 hours, leaving many northern Canadian communities without television and data services. The outage, which shut down much of the country's broadcast television for hours and cost Telesat Canada more than $15 million, generated significant media attention. Lam et al. used publicly available records to revisit the event; they looked at failure details, media coverage, recovery effort, and cost. They also used satellite and ground data to determine the precise causes of those satellite failures. The researchers traced the entire space weather event from conditions on the Sun through the interplanetary medium to the particle environment in geostationary orbit.

  11. The Genetic Challenges and Opportunities in Advanced Heart Failure.

    PubMed

    Hannah-Shmouni, Fady; Seidelmann, Sara B; Sirrs, Sandra; Mani, Arya; Jacoby, Daniel

    2015-11-01

    The causes of heart failure are diverse. Inherited causes represent an important clinical entity and can be divided into 2 major categories: familial and metabolic cardiomyopathies. The distinct features that might be present in early disease states can become broadly overlapping with other diseases, such as in the case of inherited cardiomyopathies (ie, familial hypertrophic cardiomyopathy or mitochondrial diseases). In this review article, we focus on genetic issues related to advanced heart failure. Because of the emerging importance of this topic and its breadth, we sought to focus our discussion on the known genetic forms of heart failure syndromes, genetic testing, and newer data on pharmacogenetics and therapeutics in the treatment of heart failure, to primarily encourage clinicians to place a priority on the diagnosis and treatment of these potentially treatable conditions. Copyright © 2015 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  12. The calibration of photographic and spectroscopic films. 1: Film batch variations of reciprocity failure in IIaO film. 2: Thermal and aging effects in relationship to reciprocity failure. 3: Shifting of reciprocity failure points as a function of thermal and aging effects

    NASA Technical Reports Server (NTRS)

    Peters, K. A.; Atkinson, P. F.; Hammond, E. C., Jr.

    1986-01-01

    Reciprocity failure was examined for IIaO spectroscopic film. Three separate experiments were performed in order to study film batch variations, thermal and aging effects in relationship to reciprocity failure, and shifting of reciprocity failure points as a function of thermal and aging effects. The failure was examined over ranges of time between 5 and 60 seconds. The variation to illuminance was obtained by using thirty neutral density filters. A standard sensitometer device imprinted the wedge pattern on the film as exposure time was subjected to variation. The results indicate that film batch differences, temperature, and aging play an important role in reciprocity failure of IIaO spectroscopic film. A shifting of the failure points was also observed in various batches of film.

  13. The patterns and causes of neonatal mortality at a tertiary hospital in oman.

    PubMed

    Abdellatif, Mohamed; Ahmed, Masood; Bataclan, Maria Flordeliz; Khan, Ashfaq Ahmed; Al Battashi, Abeer; Al Maniri, Abdullah

    2013-11-01

    To report the patterns and causes of neonatal death from a tertiary care neonatal intensive care unit over a period of four years. This is a retrospective cohort study where four years data (January 2006 - December 2009) of all inborn neonatal admissions and deaths were collected from the neonatal intensive care unit at Sultan Qaboos University hospital on predesigned forms. All out born admissions and deaths were excluded. The causes of neonatal death were classified using Wigglesworth's classification. The number of inborn live births during the study period was 10064 and the total number of inborn neonatal admissions was 1475. The total deaths (neonatal and post neonatal) at the neonatal intensive care unit was 73 (63 inborn and 10 out born). Among the inborn, five deaths were post neonatal deaths and hence, excluded from analysis. Among the remaining inborn neonatal deaths (n=58), 34 (59%) were males and 24 (41%) were females. The number of neonatal admissions increased over the years during the study period from 248 to 356, while the number of deaths also increased from 10 deaths in 2006, to 20 deaths in 2009. The primary causes of neonatal deaths were prematurity and its complications 52% (n=30). Lethal congenital malformations lead to 17 (29%) newborn deaths, specific diagnosis in 7 newborns (12%), and birth asphyxia in four (7%) of cases. There was an increasing trend of neonatal admissions and deaths among inborn babies. Prematurity, with sepsis as its major complication and congenital malformations were the leading cause of neonatal mortality.

  14. The Patterns and Causes of Neonatal Mortality at a Tertiary Hospital in Oman

    PubMed Central

    Abdellatif, Mohamed; Ahmed, Masood; Bataclan, Maria Flordeliz; Khan, Ashfaq Ahmed; Al Battashi, Abeer; Al Maniri, Abdullah

    2013-01-01

    Objective To report the patterns and causes of neonatal death from a tertiary care neonatal intensive care unit over a period of four years. Methods This is a retrospective cohort study where four years data (January 2006 - December 2009) of all inborn neonatal admissions and deaths were collected from the neonatal intensive care unit at Sultan Qaboos University hospital on predesigned forms. All out born admissions and deaths were excluded. The causes of neonatal death were classified using Wigglesworth's classification. Results The number of inborn live births during the study period was 10064 and the total number of inborn neonatal admissions was 1475. The total deaths (neonatal and post neonatal) at the neonatal intensive care unit was 73 (63 inborn and 10 out born). Among the inborn, five deaths were post neonatal deaths and hence, excluded from analysis. Among the remaining inborn neonatal deaths (n=58), 34 (59%) were males and 24 (41%) were females. The number of neonatal admissions increased over the years during the study period from 248 to 356, while the number of deaths also increased from 10 deaths in 2006, to 20 deaths in 2009. The primary causes of neonatal deaths were prematurity and its complications 52% (n=30). Lethal congenital malformations lead to 17 (29%) newborn deaths, specific diagnosis in 7 newborns (12%), and birth asphyxia in four (7%) of cases. Conclusion There was an increasing trend of neonatal admissions and deaths among inborn babies. Prematurity, with sepsis as its major complication and congenital malformations were the leading cause of neonatal mortality. PMID:24223246

  15. Severe right heart failure in a patient with Grave's disease.

    PubMed

    Xenopoulos, N P; Braden, G A; Applegate, R J

    1996-11-01

    This brief report presents a patient with isolated right heart failure and two rare underlying causes, hyperthyroidism and dysplastic tricuspid valve. Repair of the tricuspid valve and treatment of the hyperthyroidism were both essential for successful treatment of the right heart failure. Most important, recrudescence of hyperthyroidism in this patient was associated with reappearance of florid right heart failure. This report provides further information about a potential linkage of hyperthyroidism and severe right heart failure.

  16. Collocation and Pattern Recognition Effects on System Failure Remediation

    NASA Technical Reports Server (NTRS)

    Trujillo, Anna C.; Press, Hayes N.

    2007-01-01

    Previous research found that operators prefer to have status, alerts, and controls located on the same screen. Unfortunately, that research was done with displays that were not designed specifically for collocation. In this experiment, twelve subjects evaluated two displays specifically designed for collocating system information against a baseline that consisted of dial status displays, a separate alert area, and a controls panel. These displays differed in the amount of collocation, pattern matching, and parameter movement compared to display size. During the data runs, subjects kept a randomly moving target centered on a display using a left-handed joystick and they scanned system displays to find a problem in order to correct it using the provided checklist. Results indicate that large parameter movement aided detection and then pattern recognition is needed for diagnosis but the collocated displays centralized all the information subjects needed, which reduced workload. Therefore, the collocated display with large parameter movement may be an acceptable display after familiarization because of the possible pattern recognition developed with training and its use.

  17. [Molecular characterization and antimicrobial susceptibility pattern of extended-spectrum β-lactamase-producing Escherichia coli as cause of community acquired urinary tract infection].

    PubMed

    Galindo-Méndez, Mario

    Background Community acquired urinary tract infections (CaUTI) caused by strains of extended-spectrum β-lactamases (ESBL) - producing Escherichia coli, mainly by strains carrying the blaCTX-M-15 gene, is a growing phenomenon worldwide. Aim To determine the antibiotic susceptibility pattern of ESBL-producing E. coli as cause of CaUTI and to identify their molecular pattern. Methods A descriptive study was performed in the city of Oaxaca, Mexico, from where 288 strains of CaUTI-producing strains of E. coli in adults with possible UTI were isolated. The CLSI criteria was followed to determine the antimicrobial susceptibility patterns, and their molecular characterization was performed by using PCR. Results 31.3% of E. coli strains isolated in our population were ESBL producers, which presented higher levels of antibiotic resistance than those of non-producers of these enzymes. 95.6% of the studied strains were carriers of the blaCTX-M gene. Conclusions One-third of the Ca-UTI caused by E. coli in our population are caused by ESBL-producing strains, which present high levels of resistance to the antibiotics widely used in our community. This situation considerably decreases the number of antibiotics available for an empiric treatment against these infections.

  18. Comparison of tensile strength among simple interrupted, cruciate, intradermal, and subdermal suture patterns for incision closure in ex vivo canine skin specimens.

    PubMed

    Zellner, Eric M; Hedlund, Cheryl S; Kraus, Karl H; Burton, Andrew F; Kieves, Nina R

    2016-06-15

    OBJECTIVE To compare suture placement time, tension at skin separation and suture line failure, and mode of failure among 4 suture patterns. DESIGN Randomized trial. SAMPLE 60 skin specimens from the pelvic limbs of 30 purpose-bred Beagles. PROCEDURES Skin specimens were harvested within 2 hours after euthanasia and tested within 6 hours after harvest. An 8-cm incision was made in each specimen and sutured with 1 of 4 randomly assigned suture patterns (simple interrupted, cruciate, intradermal, or subdermal). Suture placement time and percentage of skin apposition were evaluated. Specimens were mounted in a calibrated material testing machine and distracted until suture line failure. Tensile strength at skin-edge separation and suture-line failure and mode of failure were compared among the 4 patterns. RESULTS Mean suture placement time for the cruciate pattern was significantly less than that for other patterns. Percentage of skin apposition did not differ among the 4 patterns. Mean tensile strength at skin-edge separation and suture-line failure for the simple interrupted and cruciate patterns were significantly higher than those for the intradermal and subdermal patterns. Mean tensile strength at skin-edge separation and suture-line failure did not differ significantly between the intradermal and subdermal patterns or the simple interrupted and cruciate patterns. The primary mode of failure for the simple interrupted pattern was suture breakage, whereas that for the cruciate, intradermal, and subdermal patterns was tissue failure. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested external skin sutures may be preferred for closure of incisions under tension to reduce risk of dehiscence.

  19. Anger, hostility, and hospitalizations in patients with heart failure.

    PubMed

    Keith, Felicia; Krantz, David S; Chen, Rusan; Harris, Kristie M; Ware, Catherine M; Lee, Amy K; Bellini, Paula G; Gottlieb, Stephen S

    2017-09-01

    Heart failure patients have a high hospitalization rate, and anger and hostility are associated with coronary heart disease morbidity and mortality. Using structural equation modeling, this prospective study assessed the predictive validity of anger and hostility traits for cardiovascular and all-cause rehospitalizations in patients with heart failure. 146 heart failure patients were administered the STAXI and Cook-Medley Hostility Inventory to measure anger, hostility, and their component traits. Hospitalizations were recorded for up to 3 years following baseline. Causes of hospitalizations were categorized as heart failure, total cardiac, noncardiac, and all-cause (sum of cardiac and noncardiac). Measurement models were separately fit for Anger and Hostility, followed by a Confirmatory Factor Analysis to estimate the relationship between the Anger and Hostility constructs. An Anger model consisted of State Anger, Trait Anger, Anger Expression Out, and Anger Expression In, and a Hostility model included Cynicism, Hostile Affect, Aggressive Responding, and Hostile Attribution. The latent construct of Anger did not predict any of the hospitalization outcomes, but Hostility significantly predicted all-cause hospitalizations. Analyses of individual trait components of each of the 2 models indicated that Anger Expression Out predicted all-cause and noncardiac hospitalizations, and Trait Anger predicted noncardiac hospitalizations. None of the individual components of Hostility were related to rehospitalizations or death. The construct of Hostility and several components of Anger are predictive of hospitalizations that were not specific to cardiac causes. Mechanisms common to a variety of health problems, such as self-care and risky health behaviors, may be involved in these associations. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. Effects of traffic generation patterns on the robustness of complex networks

    NASA Astrophysics Data System (ADS)

    Wu, Jiajing; Zeng, Junwen; Chen, Zhenhao; Tse, Chi K.; Chen, Bokui

    2018-02-01

    Cascading failures in communication networks with heterogeneous node functions are studied in this paper. In such networks, the traffic dynamics are highly dependent on the traffic generation patterns which are in turn determined by the locations of the hosts. The data-packet traffic model is applied to Barabási-Albert scale-free networks to study the cascading failures in such networks and to explore the effects of traffic generation patterns on network robustness. It is found that placing the hosts at high-degree nodes in a network can make the network more robust against both intentional attacks and random failures. It is also shown that the traffic generation pattern plays an important role in network design.

  1. Psychological distress and mortality in systolic heart failure.

    PubMed

    Pelle, Aline J; Pedersen, Susanne S; Schiffer, Angélique A; Szabó, Balázs; Widdershoven, Jos W; Denollet, Johan

    2010-03-01

    Depression, anxiety, and type D ("distressed") personality (tendency to experience negative emotions paired with social inhibition) have been associated with poor prognosis in coronary heart disease, but little is known about their role in chronic heart failure. Therefore, we investigated whether these indicators of psychological distress are associated with mortality in chronic heart failure. Consecutive outpatients with chronic heart failure (n=641; 74.3% men; mean age, 66.6+/-10.0 years) filled out a 4-item questionnaire to assess mixed symptoms of anxiety and depression and the 14-item type D scale. End points were defined as all-cause and cardiac mortality. After a mean follow-up of 37.6+/-15.6 months, 123 deaths (76 due to cardiac cause) were recorded. Cumulative hazard functions for elevated anxiety/depression symptoms differed marginally for all-cause (P=0.06), but not cardiac, mortality (P=0.43); type D personality was associated with neither all-cause mortality (P=0.63) nor cardiac mortality (P=0.87). In multivariable analyses, neither elevated anxiety/depression symptoms nor type D personality was associated with all-cause mortality (hazard ratio [HR]=1.18; 95% CI, 0.76 to 1.84; P=0.45 and HR=1.09; 95% CI, 0.67 to 1.77; P=0.73, respectively) or cardiac mortality (HR=1.13; 95% CI, 0.63 to 2.04; P=0.65 and HR=1.16; 95% CI, 0.62 to 2.18; P=0.67). In secondary analyses, a 1-point increase in anxiety/depression (range, 0 to 16) was associated with an 8% increase in risk for all-cause mortality (HR=1.08; 95% CI, 1.01 to 1.15; P=0.02). Neither elevated anxiety/depression symptoms nor type D personality was associated with an increased risk for all-cause or cardiac mortality. Future studies with adequate power and a longer follow-up duration are needed to further elucidate the role of psychological distress in chronic heart failure.

  2. Causes and correlates of anemia in 200 patients with acute cardiogenic pulmonary edema.

    PubMed

    Rovellini, Angelo; Graziadei, Giovanna; Folli, Christian; Brambilla, Anna Maria; Cosentini, Roberto; Canetta, Ciro; Monzani, Valter

    2012-12-01

    Acute heart failure has a poor prognosis and the presence of anemia may increase the risk of adverse outcomes. However, the clinical and laboratory characteristics of anemia in acute heart failure are poorly known. We aimed to assess the causes and the clinical and laboratory correlates of anemia in patients with acute cardiogenic pulmonary edema (ACPE). This observational study, performed in an Emergency Unit, enrolled 200 patients treated with medical therapy and continuous positive airway pressure. Anemia was found in 36% of patients (38.5% of females and 32.5% of males) and was severe (hemoglobin <9 g/dL) in 6.9% of cases. The most frequent causes of anemia were chronic renal failure (27.8%), chronic inflammatory states (27.8%) and the clustering of multiple factors (18.1%). A wider spectrum of etiological factors was found in females than in males. Microcytic anemia was observed only in females (20% of those anemic), mainly due to iron deficiency/chronic blood loss. Glomerular filtration rate, serum iron, serum albumin, total cholesterol and diastolic blood pressure were independently associated with hemoglobin levels. The etiology of anemia in ACPE is heterogeneous, with several causal factors besides impaired renal function. The pattern of anemia is different between genders, suggesting that sex-specific diagnostic and therapeutic targets should be implemented. Copyright © 2012 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

  3. Six minute walk test predicts long-term all-cause mortality and heart failure rehospitalization in African-American patients hospitalized with acute decompensated heart failure.

    PubMed

    Alahdab, M Tarek; Mansour, Ibrahim N; Napan, Sirikarn; Stamos, Thomas D

    2009-03-01

    The prognostic value of the 6-minute walk test (6MWT) has been described in patients with heart failure (HF); however, limited data are available in an African-American (AA) population. We prospectively evaluated the usefulness of the 6MWT in predicting mortality and HF rehospitalization in AA patients with acute decompensated HF. Two hundred AA patients (63.1% men, mean age 55.7 +/- 12.9 years) with acute decompensated HF were prospectively studied. Patients were followed to assess 40-month all-cause mortality and 18-month HF rehospitalization. The median distance walked on the 6MWT was 213 m. Of the 198 patients with available mortality data, 59 patients (29.8%) died. Of the 191 patients with available rehospitalization data, 114 (59.7%) were rehospitalized for worsening HF. For patients who walked 200 m (P = .001). For patients who walked 200 m (P = .027). Multivariate Cox regression analysis showed that 6MWT distance cause mortality and HF rehospitalization.

  4. Recent advances in the epidemiology, pathogenesis and prognosis of acute heart failure and cardiomyopathy in Africa.

    PubMed

    Sliwa, Karen; Mayosi, Bongani M

    2013-09-01

    This review addresses recent advances in the epidemiology, pathogenesis and prognosis of acute heart failure and cardiomyopathy based on research conducted in Africa. We searched Medline/PubMed for publications on acute decompensated heart failure and cardiomyopathy in Africa for the past 5 years (ie, 1 January 2008 to 31 December 2012). This was supplemented with personal communications with colleagues from Africa working in the field. A large prospective registry has shown that acute decompensated heart failure is caused by hypertension, cardiomyopathy and rheumatic heart disease in 90% of cases, a pattern that is in contrast with the dominance of coronary artery disease in North America and Europe. Furthermore, acute heart failure is a disease of the young with a mean age of 52 years, occurs equally in men and women, and is associated with high mortality at 6 months (∼18%), which is, however, similar to that observed in non-African heart failure registries, suggesting that heart failure has a dire prognosis globally, regardless of aetiology. The molecular genetics of dilated cardiomyopathy, hypertrophic cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy in Africans is consistent with observations elsewhere in the world; the unique founder effects in the Afrikaner provide an opportunity for the study of genotype-phenotype correlations in large numbers of individuals with cardiomyopathy due to the same mutation. Advances in the understanding of the molecular mechanisms of peripartum cardiomyopathy have led to promising clinical trials of bromocriptine in the treatment of peripartum heart failure. The key challenges of management of heart failure are the urgent need to increase the use of proven treatments by physicians, and the control of hypertension in primary care and at the population level.

  5. Organizational Failure in an NHS Hospital Trust: A Qualitative Study.

    PubMed

    Ravaghi, Hamid; Mannion, Russell; Sajadi, Haniye Sadat

    2015-01-01

    The objective was to explore the key factors associated with organizational failure in an NHS Hospital Trust. This case study adopted a qualitative design. Fifty-seven semistructured interviews and document analyses were conducted as well. Data were analyzed using a framework analysis method. A range of symptoms of organizational performance failure was identified. These relate to a financial deficit, lack of good external relationships, inability to meet core targets, a lack of clear management systems, and low staff morale. These markers had not been taken seriously by the previous senior management team. Symptoms of failure were the reflection of presence of secondary and primary causes of failure. Poor managerial leadership, poor financial control and performance management, lack of open culture, distraction by 2 large projects, and the lack of clinician engagement were perceived as internal causes of failure and the high level of policy changes within the NHS as the key external cause. The level of deprivation in the area was also thought to have had a negative impact on performance. The findings reinforce and expand on those of recent studies across the public sector. Tracking an organization's performance and early diagnosis of performance problems, focusing on performance management systems, and taking into account contextual factors are issues that should be considered.

  6. Failure to recall.

    PubMed

    Laming, Donald

    2009-01-01

    Mathematical analysis shows that if the pattern of rehearsal in free-recall experiments (of necessity, the pattern observed when participants rehearse aloud) be continued without any further interruption by stimuli (as happens during recall), it terminates with the retrieval of the same 1 word over and over again. Such a terminal state is commonly reached before some of the words in the list have been retrieved even once; those words are not recalled. The 1 minute frequently allowed for recall in free-recall experiments is ample time for retrieval to seize up in this way. The author proposes a model that represents the essential features of the pattern of rehearsal; validates that model by reference to the overt rehearsal data from B. B. Murdock, Jr., and J. Metcalfe (1978) and the recall data from B. B. Murdock, Jr., and R. Okada (1970); demonstrates the long-term properties of continued sequences of retrievals and, also, a fundamental relation linking recall to the total time of presentation; and, finally, compares failure to recall in free-recall experiments with forgetting in general.

  7. Yogi Detox Tea: A Potential Cause of Acute Liver Failure

    PubMed Central

    Kang, Mitchell; Shin, Jaewook James; Rothstein, Kenneth

    2017-01-01

    We present a case of acute fulminant liver failure from a liver detoxification tea. We present a 60-year-old female with weakness, lethargy, scleral icterus, jaundice, and worsening mental status. She drank herbal tea three times a day for 14 days prior to symptom development. Liver tests were elevated. Remaining laboratory tests and imaging were negative for other etiologies. An ultrasound-guided liver biopsy showed submassive necrosis. A literature search on the ingredients shows six ingredients as having hepatotoxic effects and remaining ingredients as having very sparse hepatoprotective data. Healthcare professionals should discuss herbal medication and tea use and report adverse effects. PMID:29204300

  8. Care management for low-risk patients with heart failure: a randomized, controlled trial.

    PubMed

    DeBusk, Robert Frank; Miller, Nancy Houston; Parker, Kathleen Marie; Bandura, Albert; Kraemer, Helena Chmura; Cher, Daniel Joseph; West, Jeffrey Alan; Fowler, Michael Bruce; Greenwald, George

    2004-10-19

    Nurse care management programs for patients with chronic illness have been shown to be safe and effective. To determine whether a telephone-mediated nurse care management program for heart failure reduced the rate of rehospitalization for heart failure and for all causes over a 1-year period. Randomized, controlled trial of usual care with nurse management versus usual care alone in patients hospitalized for heart failure from May 1998 through October 2001. 5 northern California hospitals in a large health maintenance organization. Of 2786 patients screened, 462 met clinical criteria for heart failure and were randomly assigned (228 to intervention and 234 to usual care). Nurse care management provided structured telephone surveillance and treatment for heart failure and coordination of patients' care with primary care physicians. Time to first rehospitalization for heart failure or for any cause and time to a combined end point of first rehospitalization, emergency department visit, or death. At 1 year, half of the patients had been rehospitalized at least once and 11% had died. Only one third of rehospitalizations were for heart failure. The rate of first rehospitalization for heart failure was similar in both groups (proportional hazard, 0.85 [95% CI, 0.46 to 1.57]). The rate of all-cause rehospitalization was similar (proportional hazard, 0.98 [CI, 0.76 to 1.27]). The findings of this study, conducted in a single health care system, may not be generalizable to other health care systems. The overall effect of the intervention was minor. Among patients with heart failure at low risk on the basis of sociodemographic and medical attributes, nurse care management did not statistically significantly reduce rehospitalizations for heart failure or for any cause. Such programs may be less effective for patients at low risk than those at high risk.

  9. Causes and prevention of splitting/bursting failure of concrete crossties: a computational study

    DOT National Transportation Integrated Search

    2017-09-17

    Concrete splitting/bursting is a well-known failure mode of concrete crossties that can compromise the crosstie integrity and raise railroad maintenance and track safety concerns. This paper presents a computational study aimed at better understandin...

  10. [Obesity and the prognosis of heart failure: the obesity paradox, myth or reality?].

    PubMed

    Bounhoure, Jean-Paul; Galinier, Michel; Roncalli, Jerôme; Massabuau, Pierre

    2014-01-01

    Obesity has now reached epidemic proportions worldwide. Obesity is associated with numerous comorbidities, including hypertension, lipid disorders and type II diabetes, and is also a major cause of cardiovascular disease, coronary disease, heart failure, atrial fibrillation, and sudden death. Obesity is the main cause of heart failure in respectively 11% and 14% of cases in men and women. The Framingham study showed that, after correction for other risk factors, each point increase in the body mass index raises the risk of heart failure by 5% in men and 7% in women. Obesity increases the heart workload, causes left ventricular hypertrophy, and impairs both diastolic and systolic function. The most common form of heart failure is diastolic dysfunction, and heart failure in obese individuals is associated with preserved systolic function. Despite these comorbidities and the severity of heart failure, numerous studies have revealed an "obesity paradox" in which overweight and obese individuals with heart failure appear to have a better prognosis than non overweight subjects. This review summarizes the adverse cardiac effects of this nutritional disease, the results of some studies supporting the obesity paradox, the better survival rate of obese patients with heart failure. Potential explanations for these surprising data include the possibility that a number of obese patients may simply not have heart failure, as well as methodological bias, and protective effects of adipose tissue. Further studies of large populations are needed to determine how obesity may improve the prognosis of heart failure.

  11. Decompensated Heart Failure in Pregnancy

    PubMed Central

    Anthony, John

    2016-01-01

    Heart disease is a common cause of morbidity and mortality during pregnancy. Symptoms and signs of heart failure in a pregnant woman are an indication for urgent assessment to establish a diagnosis and appropriate management. This is best accomplished through a multidisciplinary approach in which both cardiologists and obstetricians need to participate in order to provide expert counselling and care in pursuit of safe motherhood. Congenital heart disease, although common, once corrected is an unusual source of complications, which are more likely to develop as a consequence of ventricular failure, pulmonary hypertension and aortic arch disease. Rheumatic valvular heart disease is a challenge because of the need for anticoagulation during pregnancy and the risk of sepsis associated with childbirth. This review outlines a contemporary approach to heart failure presenting during pregnancy. PMID:28785449

  12. Humoral immunity in heart failure.

    PubMed

    Sarkar, Amrita; Rafiq, Khadija

    2018-05-17

    Cardiovascular disease (CVD) is a class of diseases that involve disorders of heart and blood vessels, including: hypertension, coronary heart disease, cerebrovascular disease, peripheral vascular disease, which finally lead to heart failure (HF). There are several treatments available all over the world, but still CVD and heart failure became the number one problem causing death every year worldwide. Both experimental and clinical studies have shown a role for inflammation in the pathogenesis of heart failure. This seems related to an imbalance between pro-inflammatory and anti-inflammatory cytokines. Cardiac inflammation is major pathophysiological mechanism operating in the failing heart, regardless of HF aetiology. Disturbances of the cellular and humoral immune system are frequently observed in heart failure. This review describes how B-cells play specific role in the heart failure states. There is an urgent need to identify novel therapeutic targets and develop advanced therapeutic strategies to combat the syndrome of HF. Understanding and describing the elements of the humoral immunity function are essential, and may suggest potential new treatment strategies. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  13. The evolving landscape of quality measurement for heart failure

    PubMed Central

    Fitzgerald, Ashley A.; Allen, Larry A.; Masoudi, Frederick A.

    2013-01-01

    Heart failure (HF) is a major cause of mortality and morbidity, representing a leading cause of death and hospitalization among U.S. Medicare beneficiaries. Advances in science have generated effective interventions to reduce adverse outcomes in HF, particularly in patients with reduced left ventricular ejection fraction. Unfortunately, effective therapies for heart failure are often not utilized in an effective, safe, timely, equitable, patient-centered, and efficient manner. Further, the risk of adverse outcomes for HF remains high. The last decades have witnessed the growth of efforts to measure and improve the care and outcomes of patients with HF. This paper will review the evolution of quality measurement for HF, including a brief history of quality measurement in medicine; the measures that have been employed to characterize quality in heart failure; how the measures are obtained; how measures are employed; and present and future challenges surrounding quality measurement in heart failure. PMID:22548579

  14. Diuretics as pathogenetic treatment for heart failure

    PubMed Central

    Guglin, Maya

    2011-01-01

    Increased intracardiac filling pressure or congestion causes symptoms and leads to hospital admissions in patients with heart failure, regardless of their systolic function. A history of hospital admission, in turn, predicts further hospitalizations and morbidity, and a higher number of hospitalizations determine higher mortality. Congestion is therefore the driving force of the natural history of heart failure. Congestion is the syndrome shared by heart failure with preserved and reduced systolic function. These two conditions have almost identical morbidity, mortality, and survival because the outcomes are driven by congestion. A small difference in favor of heart failure with preserved systolic function comes from decreased ejection fraction and left ventricular remodeling which is only present in heart failure with decreased systolic function. The magnitude of this difference reflects the contribution of decreased systolic function and ventricular remodeling to the progression of heart failure. The only treatment available for congestion is fluid removal via diuretics, ultrafiltration, or dialysis. It is the only treatment that works equally well for heart failure with reduced and preserved systolic function because it affects congestion, the main pathogenetic feature of the disease. Diuretics are pathogenetic therapy for heart failure. PMID:21403798

  15. Valve system incorporating single failure protection logic

    DOEpatents

    Ryan, Rodger; Timmerman, Walter J. H.

    1980-01-01

    A valve system incorporating single failure protective logic. The system consists of a valve combination or composite valve which allows actuation or de-actuation of a device such as a hydraulic cylinder or other mechanism, integral with or separate from the valve assembly, by means of three independent input signals combined in a function commonly known as two-out-of-three logic. Using the input signals as independent and redundant actuation/de-actuation signals, a single signal failure, or failure of the corresponding valve or valve set, will neither prevent the desired action, nor cause the undesired action of the mechanism.

  16. Precise design-based defect characterization and root cause analysis

    NASA Astrophysics Data System (ADS)

    Xie, Qian; Venkatachalam, Panneerselvam; Lee, Julie; Chen, Zhijin; Zafar, Khurram

    2017-03-01

    that human operators will typically miss), to obtain the exact defect location on design, to compare all defective patterns thus detected against a library of known patterns, and to classify all defective patterns as either new or known. By applying the computer to these tasks, we automate the entire process from defective pattern identification to pattern classification with high precision, and we perform this operation en masse during R & D, ramp, and volume production. By adopting the methodology, whenever a specific weak pattern is identified, we are able to run a series of characterization operations to ultimately arrive at the root cause. These characterization operations can include (a) searching all pre-existing Review SEM images for the presence of the specific weak pattern to determine whether there is any spatial (within die or within wafer) or temporal (within any particular date range, before or after a mask revision, etc.) correlation and (b) understanding the failure rate of the specific weak pattern to prioritize the urgency of the problem, (c) comparing the weak pattern against an OPC (Optical Procimity Correction) Verification report or a PWQ (Process Window Qualification)/FEM (Focus Exposure Matrix) result to assess the likelihood of it being a litho-sensitive pattern, etc. After resolving the specific weak pattern, we will categorize it as known pattern, and the engineer will move forward with discovering new weak patterns.

  17. Preventing medical errors by designing benign failures.

    PubMed

    Grout, John R

    2003-07-01

    One way to successfully reduce medical errors is to design health care systems that are more resistant to the tendencies of human beings to err. One interdisciplinary approach entails creating design changes, mitigating human errors, and making human error irrelevant to outcomes. This approach is intended to facilitate the creation of benign failures, which have been called mistake-proofing devices and forcing functions elsewhere. USING FAULT TREES TO DESIGN FORCING FUNCTIONS: A fault tree is a graphical tool used to understand the relationships that either directly cause or contribute to the cause of a particular failure. A careful analysis of a fault tree enables the analyst to anticipate how the process will behave after the change. EXAMPLE OF AN APPLICATION: A scenario in which a patient is scalded while bathing can serve as an example of how multiple fault trees can be used to design forcing functions. The first fault tree shows the undesirable event--patient scalded while bathing. The second fault tree has a benign event--no water. Adding a scald valve changes the outcome from the undesirable event ("patient scalded while bathing") to the benign event ("no water") Analysis of fault trees does not ensure or guarantee that changes necessary to eliminate error actually occur. Most mistake-proofing is used to prevent simple errors and to create well-defended processes, but complex errors can also result. The utilization of mistake-proofing or forcing functions can be thought of as changing the logic of a process. Errors that formerly caused undesirable failures can be converted into the causes of benign failures. The use of fault trees can provide a variety of insights into the design of forcing functions that will improve patient safety.

  18. Exercise performance, haemodynamics, and respiratory pattern do not identify heart failure patients who end exercise with dyspnoea from those with fatigue.

    PubMed

    Morosin, Marco; Farina, Stefania; Vignati, Carlo; Spadafora, Emanuele; Sciomer, Susanna; Salvioni, Elisabetta; Sinagra, Gianfranco; Agostoni, Piergiuseppe

    2018-02-01

    The two main symptoms referred by chronic heart failure (HF) patients as the causes of exercise termination during maximal cardiopulmonary exercise testing (CPET) are muscular fatigue and dyspnoea. So far, a physiological explanation why some HF patients end exercise because of dyspnoea and others because of fatigue is not available. We assessed whether patients referring dyspnoea or muscular fatigue may be distinguished by different ventilator or haemodynamic behaviours during exercise. We analysed exercise data of 170 consecutive HF patients with reduced left ventricular ejection fraction in stable clinical condition. All patients underwent maximal CPET and a second maximal CPET with measurement of cardiac output by inert gas rebreathing at peak exercise. Thirty-eight (age 65.0 ± 11.1 years) and 132 (65.1 ± 11.4 years) patients terminated CPET because of dyspnoea and fatigue, respectively. Haemodynamic and cardiorespiratory parameters were the same in fatigue and dyspnoea patients. VO 2 was 10.4 ± 3.2 and 10.5 ± 3.3 mL/min/kg at the anaerobic threshold and 15.5 ± 4.8 and 15.4 ± 4.3 at peak, in fatigue and dyspnoea patients, respectively. In fatigue and dyspnoea patients, peak heart rate was 110 ± 22 and 114 ± 22 beats/min, and VE/VCO 2 and VO 2 /work relationship slopes were 31.2 ± 6.8 and 30.6 ± 8.2 and 10.6 ± 4.2 and 11.4 ± 5.5 L/min/W, respectively. Peak cardiac output was 6.68 ± 2.51 and 6.21 ± 2.55 L/min (P = NS for all). In chronic HF patients in stable clinical condition, fatigue and dyspnoea as reasons of exercise termination do not highlight different ventilatory or haemodynamic patterns during effort. © 2017 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.

  19. Total artificial heart implantation for biventricular failure due to eosinophilic myocarditis.

    PubMed

    Kawabori, Masashi; Kurihara, Chitaru; Miller, Yair; Heck, Kent A; Bogaev, Roberta C; Civitello, Andrew B; Cohn, William E; Frazier, O H; Morgan, Jeffrey A

    2017-09-01

    Idiopathic hypereosinophilic syndrome is a condition of unknown etiology characterized by proliferation of eosinophils and their infiltration into tissues. Although cardiac involvement is rare, eosinophilic myocarditis can lead to life-threating fulminant congestive heart failure. Treatment of patients with eosinophilic myocarditis is challenging as heart failure can be caused by biventricular dysfunction. To our knowledge, this is the first case reported in the literature describing a patient with acute severe biventricular heart failure caused by eosinophilic myocarditis with mural left ventricular apical thrombus who was successfully treated with implantation of a total artificial heart as a bridge to heart transplant.

  20. Allergic reaction to vanadium causes a diffuse eczematous eruption and titanium alloy orthopedic implant failure.

    PubMed

    Engelhart, Sally; Segal, Robert J

    2017-04-01

    Allergy as a cause of adverse outcomes in patients with implanted orthopedic hardware is controversial. Allergy to titanium-based implants has not been well researched, as titanium is traditionally thought to be inert. We highlight the case of a patient who developed systemic dermatitis and implant failure after surgical placement of a titanium alloy (Ti6Al4V) plate in the left foot. The hardware was removed and the eruption cleared in the following weeks. The plate and screws were submitted for metal analysis. The elemental composition of both the plate and screws included 3 major elements-titanium, aluminum, and vanadium-as well as trace elements. Metal analysis revealed that the plate and screws had different microstructures, and electrochemical studies demonstrated that galvanic corrosion could have occurred between the plate and screws due to their different microstructures, contributing to the release of vanadium in vivo. The patient was patch tested with several metals including components of the implant and had a positive patch test reaction only to vanadium trichloride. These findings support a diagnosis of vanadium allergy and suggests that clinicians should consider including vanadium when patch testing patients with a suspected allergic reaction to vanadium-containing implants.

  1. On a Stochastic Failure Model under Random Shocks

    NASA Astrophysics Data System (ADS)

    Cha, Ji Hwan

    2013-02-01

    In most conventional settings, the events caused by an external shock are initiated at the moments of its occurrence. In this paper, we study a new classes of shock model, where each shock from a nonhomogeneous Poisson processes can trigger a failure of a system not immediately, as in classical extreme shock models, but with delay of some random time. We derive the corresponding survival and failure rate functions. Furthermore, we study the limiting behaviour of the failure rate function where it is applicable.

  2. Global longitudinal strain corrected by RR interval is a superior predictor of all-cause mortality in patients with systolic heart failure and atrial fibrillation.

    PubMed

    Modin, Daniel; Sengeløv, Morten; Jørgensen, Peter Godsk; Bruun, Niels Eske; Olsen, Flemming Javier; Dons, Maria; Fritz Hansen, Thomas; Jensen, Jan Skov; Biering-Sørensen, Tor

    2018-04-01

    Quantification of systolic function in patients with atrial fibrillation (AF) is challenging. A novel approach, based on RR interval correction, to counteract the varying heart cycle lengths in AF has recently been proposed. Whether this method is superior in patients with systolic heart failure (HFrEF) with AF remains unknown. This study investigates the prognostic value of RR interval-corrected peak global longitudinal strain {GLSc = GLS/[RR^(1/2)]} in relation to all-cause mortality in HFrEF patients displaying AF during echocardiographic examination. Echocardiograms from 151 patients with HFrEF and AF during examination were analysed offline. Peak global longitudinal strain (GLS) was averaged from 18 myocardial segments obtained from three apical views. GLS was indexed with the square root of the RR interval {GLSc = GLS/[RR^(1/2)]}. Endpoint was all-cause mortality. During a median follow-up of 2.7 years, 40 patients (26.5%) died. Neither uncorrected GLS (P = 0.056) nor left ventricular ejection fraction (P = 0.053) was significantly associated with all-cause mortality. After RR^(1/2) indexation, GLSc became a significant predictor of all-cause mortality (hazard ratio 1.16, 95% confidence interval 1.02-1.22, P = 0.014, per %/s^(1/2) decrease). GLSc remained an independent predictor of mortality after multivariable adjustment (age, sex, mean heart rate, mean arterial blood pressure, left atrial volume index, and E/e') (hazard ratio 1.17, 95% confidence interval 1.05-1.31, P = 0.005 per %/s^(1/2) decrease). Decreasing {GLSc = GLS/[RR^(1/2)]}, but not uncorrected GLS nor left ventricular ejection fraction, was significantly associated with increased risk of all-cause mortality in HFrEF patients with AF and remained an independent predictor after multivariable adjustment. © 2017 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.

  3. Preventing Early Learning Failure.

    ERIC Educational Resources Information Center

    Sornson, Bob, Ed.

    Noting that thousands of young children with the capacity to experience school success do not because they are unprepared for school learning activities, have experienced physical or emotional setbacks that cause them to be at risk for early learning failure, have never experienced limits on their behavior, or have mild sensory or motor deficits,…

  4. Tau, amyloid, and cascading network failure across the Alzheimer's disease spectrum.

    PubMed

    Jones, David T; Graff-Radford, Jonathan; Lowe, Val J; Wiste, Heather J; Gunter, Jeffrey L; Senjem, Matthew L; Botha, Hugo; Kantarci, Kejal; Boeve, Bradley F; Knopman, David S; Petersen, Ronald C; Jack, Clifford R

    2017-12-01

    Functionally related brain regions are selectively vulnerable to Alzheimer's disease pathophysiology. However, molecular markers of this pathophysiology (i.e., beta-amyloid and tau aggregates) have discrepant spatial and temporal patterns of progression within these selectively vulnerable brain regions. Existing reductionist pathophysiologic models cannot account for these large-scale spatiotemporal inconsistencies. Within the framework of the recently proposed cascading network failure model of Alzheimer's disease, however, these large-scale patterns are to be expected. This model postulates the following: 1) a tau-associated, circumscribed network disruption occurs in brain regions specific to a given phenotype in clinically normal individuals; 2) this disruption can trigger phenotype independent, stereotypic, and amyloid-associated compensatory brain network changes indexed by changes in the default mode network; 3) amyloid deposition marks a saturation of functional compensation and portends an acceleration of the inciting phenotype specific, and tau-associated, network failure. With the advent of in vivo molecular imaging of tau pathology, combined with amyloid and functional network imaging, it is now possible to investigate the relationship between functional brain networks, tau, and amyloid across the disease spectrum within these selectively vulnerable brain regions. In a large cohort (n = 218) spanning the Alzheimer's disease spectrum from young, amyloid negative, cognitively normal subjects to Alzheimer's disease dementia, we found several distinct spatial patterns of tau deposition, including 'Braak-like' and 'non-Braak-like', across functionally related brain regions. Rather than arising focally and spreading sequentially, elevated tau signal seems to occur system-wide based on inferences made from multiple cross-sectional analyses we conducted looking at regional patterns of tau signal. Younger age-of-disease-onset was associated with 'non

  5. X-framework: Space system failure analysis framework

    NASA Astrophysics Data System (ADS)

    Newman, John Steven

    Space program and space systems failures result in financial losses in the multi-hundred million dollar range every year. In addition to financial loss, space system failures may also represent the loss of opportunity, loss of critical scientific, commercial and/or national defense capabilities, as well as loss of public confidence. The need exists to improve learning and expand the scope of lessons documented and offered to the space industry project team. One of the barriers to incorporating lessons learned include the way in which space system failures are documented. Multiple classes of space system failure information are identified, ranging from "sound bite" summaries in space insurance compendia, to articles in journals, lengthy data-oriented (what happened) reports, and in some rare cases, reports that treat not only the what, but also the why. In addition there are periodically published "corporate crisis" reports, typically issued after multiple or highly visible failures that explore management roles in the failure, often within a politically oriented context. Given the general lack of consistency, it is clear that a good multi-level space system/program failure framework with analytical and predictive capability is needed. This research effort set out to develop such a model. The X-Framework (x-fw) is proposed as an innovative forensic failure analysis approach, providing a multi-level understanding of the space system failure event beginning with the proximate cause, extending to the directly related work or operational processes and upward through successive management layers. The x-fw focus is on capability and control at the process level and examines: (1) management accountability and control, (2) resource and requirement allocation, and (3) planning, analysis, and risk management at each level of management. The x-fw model provides an innovative failure analysis approach for acquiring a multi-level perspective, direct and indirect causation of

  6. Angiotensin-neprilysin inhibition versus enalapril in heart failure.

    PubMed

    McMurray, John J V; Packer, Milton; Desai, Akshay S; Gong, Jianjian; Lefkowitz, Martin P; Rizkala, Adel R; Rouleau, Jean L; Shi, Victor C; Solomon, Scott D; Swedberg, Karl; Zile, Michael R

    2014-09-11

    We compared the angiotensin receptor-neprilysin inhibitor LCZ696 with enalapril in patients who had heart failure with a reduced ejection fraction. In previous studies, enalapril improved survival in such patients. In this double-blind trial, we randomly assigned 8442 patients with class II, III, or IV heart failure and an ejection fraction of 40% or less to receive either LCZ696 (at a dose of 200 mg twice daily) or enalapril (at a dose of 10 mg twice daily), in addition to recommended therapy. The primary outcome was a composite of death from cardiovascular causes or hospitalization for heart failure, but the trial was designed to detect a difference in the rates of death from cardiovascular causes. The trial was stopped early, according to prespecified rules, after a median follow-up of 27 months, because the boundary for an overwhelming benefit with LCZ696 had been crossed. At the time of study closure, the primary outcome had occurred in 914 patients (21.8%) in the LCZ696 group and 1117 patients (26.5%) in the enalapril group (hazard ratio in the LCZ696 group, 0.80; 95% confidence interval [CI], 0.73 to 0.87; P<0.001). A total of 711 patients (17.0%) receiving LCZ696 and 835 patients (19.8%) receiving enalapril died (hazard ratio for death from any cause, 0.84; 95% CI, 0.76 to 0.93; P<0.001); of these patients, 558 (13.3%) and 693 (16.5%), respectively, died from cardiovascular causes (hazard ratio, 0.80; 95% CI, 0.71 to 0.89; P<0.001). As compared with enalapril, LCZ696 also reduced the risk of hospitalization for heart failure by 21% (P<0.001) and decreased the symptoms and physical limitations of heart failure (P=0.001). The LCZ696 group had higher proportions of patients with hypotension and nonserious angioedema but lower proportions with renal impairment, hyperkalemia, and cough than the enalapril group. LCZ696 was superior to enalapril in reducing the risks of death and of hospitalization for heart failure. (Funded by Novartis; PARADIGM-HF Clinical

  7. Renal failure in a patient with postpolio syndrome and a normal creatinine level.

    PubMed

    Leming, Melissa K; Breyer, Michael J

    2012-01-01

    Patients with renal failure who are taking trimethoprim have an increased risk of developing hyperkalemia, which can cause muscle weakness. In patients with postpolio syndrome, a normal creatinine level could be abnormally high, renal failure is possible because of lack of creatinine production, and the muscle weakness from resultant hyperkalemia could be more severe because of their underlying condition. This abnormally high creatinine level has been termed from this point relative renal failure. The objective of the study was to review a case in which relative renal failure and hyperkalemia caused muscle weakness that manifested as shortness of breath and confusion with electrocardiographic changes. A dehydrated patient with relative renal failure and postpolio syndrome had taken trimethoprim-sulfamethoxazole that caused symptomatic hyperkalemia. The patient presented with muscle weakness, shortness of breath, and confusion, with her postpolio syndrome compounding the situation and likely making the muscle weakness more severe. A patient on trimethoprim with renal failure is at an increased risk of developing hyperkalemia. Patients with postpolio syndrome could have severe muscle weakness from the hyperkalemia and could have renal failure even with a normal creatinine level. This case report will remind treating physicians to evaluate such patients for hyperkalemia if they present with muscle weakness, especially if the patient has renal failure and is on trimethoprim. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Implications of Secondary Aftershocks for Failure Processes

    NASA Astrophysics Data System (ADS)

    Gross, S. J.

    2001-12-01

    When a seismic sequence with more than one mainshock or an unusually large aftershock occurs, there is a compound aftershock sequence. The secondary aftershocks need not have exactly the same decay as the primary sequence, with the differences having implications for the failure process. When the stress step from the secondary mainshock is positive but not large enough to cause immediate failure of all the remaining primary aftershocks, failure processes which involve accelerating slip will produce secondary aftershocks that decay more rapidly than primary aftershocks. This is because the primary aftershocks are an accelerated version of the background seismicity, and secondary aftershocks are an accelerated version of the primary aftershocks. Real stress perturbations may be negative, and heterogeneities in mainshock stress fields mean that the real world situation is quite complicated. I will first describe and verify my picture of secondary aftershock decay with reference to a simple numerical model of slipping faults which obeys rate and state dependent friction and lacks stress heterogeneity. With such a model, it is possible to generate secondary aftershock sequences with perturbed decay patterns, quantify those patterns, and develop an analysis technique capable of correcting for the effect in real data. The secondary aftershocks are defined in terms of frequency linearized time s(T), which is equal to the number of primary aftershocks expected by a time T, $ s ≡ ∫ t=0T n(t) dt, where the start time t=0 is the time of the primary aftershock, and the primary aftershock decay function n(t) is extrapolated forward to the times of the secondary aftershocks. In the absence of secondary sequences the function s(T)$ re-scales the time so that approximately one event occurs per new time unit; the aftershock sequence is gone. If this rescaling is applied in the presence of a secondary sequence, the secondary sequence is shaped like a primary aftershock sequence

  9. Probabilistic analysis on the failure of reactivity control for the PWR

    NASA Astrophysics Data System (ADS)

    Sony Tjahyani, D. T.; Deswandri; Sunaryo, G. R.

    2018-02-01

    The fundamental safety function of the power reactor is to control reactivity, to remove heat from the reactor, and to confine radioactive material. The safety analysis is used to ensure that each parameter is fulfilled during the design and is done by deterministic and probabilistic method. The analysis of reactivity control is important to be done because it will affect the other of fundamental safety functions. The purpose of this research is to determine the failure probability of the reactivity control and its failure contribution on a PWR design. The analysis is carried out by determining intermediate events, which cause the failure of reactivity control. Furthermore, the basic event is determined by deductive method using the fault tree analysis. The AP1000 is used as the object of research. The probability data of component failure or human error, which is used in the analysis, is collected from IAEA, Westinghouse, NRC and other published documents. The results show that there are six intermediate events, which can cause the failure of the reactivity control. These intermediate events are uncontrolled rod bank withdrawal at low power or full power, malfunction of boron dilution, misalignment of control rod withdrawal, malfunction of improper position of fuel assembly and ejection of control rod. The failure probability of reactivity control is 1.49E-03 per year. The causes of failures which are affected by human factor are boron dilution, misalignment of control rod withdrawal and malfunction of improper position for fuel assembly. Based on the assessment, it is concluded that the failure probability of reactivity control on the PWR is still within the IAEA criteria.

  10. Tube Failure Mechanisms.

    DTIC Science & Technology

    studies will be made: ( a ) An investigation of the factors influencing electrical breakdown in a vacuum and across the surface of a dielectric. (b) An...The purpose of this program is to investigate the nature and the principal causes of failures in microwave tubes. In this context, the following...investigation of the various electrical and surface properties of materials commonly used in microwave tubes, i.e., OFHC copper, alumina ceramic, tungsten

  11. Syndrome complex of bone marrow failure and pulmonary fibrosis predicts germline defects in telomerase

    PubMed Central

    Parry, Erin M.; Alder, Jonathan K.; Qi, Xiaodong; Chen, Julian J.-L.

    2011-01-01

    Mutations in the essential telomerase components hTERT and hTR cause dyskeratosis congenita, a bone marrow failure syndrome characterized by mucocutaneous features. Some (∼ 3%) sporadic aplastic anemia (AA) and idiopathic pulmonary fibrosis cases also carry mutations in hTERT and hTR. Even though it can affect clinical outcome, because the mutation frequency is rare, genetic testing is not standard. We examined whether the cooccurrence of bone marrow failure and pulmonary fibrosis in the same individual or family enriches for the presence of a telomerase mutation. Ten consecutive individuals with a total of 36 family members who fulfilled these criteria carried a germline mutant telomerase gene (100%). The mean age of onset for individuals with AA was significantly younger than that for those with pulmonary fibrosis (14 vs 51; P < .0001). Families displayed autosomal dominant inheritance and there was an evolving pattern of genetic anticipation, with the older generation primarily affected by pulmonary fibrosis and successive generations by bone marrow failure. The cooccurrence of AA and pulmonary fibrosis in a single patient or family is highly predictive for the presence of a germline telomerase defect. This diagnosis affects the choice of bone marrow transplantation preparative regimen and can prevent morbidity. PMID:21436073

  12. Examining the Causes of Memory Strength Variability: Recollection, Attention Failure, or Encoding Variability?

    ERIC Educational Resources Information Center

    Koen, Joshua D.; Aly, Mariam; Wang, Wei-Chun; Yonelinas, Andrew P.

    2013-01-01

    A prominent finding in recognition memory is that studied items are associated with more variability in memory strength than new items. Here, we test 3 competing theories for why this occurs--the "encoding variability," "attention failure", and "recollection" accounts. Distinguishing among these theories is critical…

  13. Thrombotic microangiopathy: An unusual cause of renal failure in rheumatoid arthritis.

    PubMed

    Sakthirajan, R; Dhanapriya, J; Dineshkumar, T; Gopalakrishnan, N; Murugan, S; Balasubramaniyan, T

    2017-01-01

    Rheumatoid arthritis (RA) is one of the commonest rheumatological diseases. Renal involvement is not common but can occur as a result of chronic inflammation as part of disease process or drug toxicity. Thrombotic microangiopathy (TMA) is characterized by microangiopathic hemolytic anemia, thrombocytopenia, and organ failure of variable severity. Only a few cases of TMA in patients with RA were reported to date. We describe a 45-year-old female patient with RA who presented with oliguria and edema. Renal biopsy showed TMA with patchy cortical necrosis. She improved with hemodialysis and plasmapheresis.

  14. Study of simple CFRP-metal joint failure

    NASA Astrophysics Data System (ADS)

    Cheng, Jingquan; Rodriguez, Antonio; Emerson, Nicolas; Symmes, Arthur

    2008-07-01

    In millimeter wavelength telescope design and construction, there have been a number of mysterious failures of simple CFRF-metal joints. Telescope designers have not had satisfactory interpretations of these failures. In this paper, factors which may influence the failure of joints are discussed. These include stress concentration, material creep, joint fatigue, reasons related to chemical process and manufacture process. Extrapolation formulas for material creep, joint fatigue, and differential thermal stresses are derived in this paper. Detailed chemical and manufacturing factors are also discussed. All these issues are the causes of a number of early failures under a loading which is significantly lower than the strength of adhesives used. For ensuring reliability of a precision instrument structure joint, the designer should have a thorough understanding of all these factors.

  15. Independent Review Support for Phoenix Mars Mission Robotic Arm Brush Motor Failure

    NASA Technical Reports Server (NTRS)

    McManamen, John P.; Pellicciotti, Joseph; DeKramer, Cornelis; Dube, Michael J.; Peeler, Deborah; Muirhead, Brian K.; Sevilla, Donald R.; Sabahi, Dara; Knopp, Michael D.

    2007-01-01

    The Phoenix Project requested the NASA Engineering and Safety Center (NESC) perform an independent peer review of the Robotic Arm (RA) Direct Current (DC) motor brush anomalies that originated during the Mars Exploration Rover (MER) Project and recurred during the Phoenix Project. The request was to evaluate the Phoenix Project investigation efforts and provide an independent risk assessment. This includes a recommendation for additional work and assessment of the flight worthiness of the RA DC motors. Based on the investigation and findings contained within this report, the IRT concurs with the risk assessment Failure Cause / Corrective Action (FC/CA) by the project, "Failure Effect Rating "3"; Major Degradation or Total Loss of Function, Failure Cause/Corrective Action Rating Currently "4"; Unknown Cause, Uncertainty in Corrective Action."

  16. Poison hemlock-induced respiratory failure in a toddler.

    PubMed

    West, Patrick L; Horowitz, B Zane; Montanaro, Marc T; Lindsay, James N

    2009-11-01

    The ingestion of poison hemlock, or Conium maculatum, is described in a 2-year-old boy. He had the onset of abdominal pain and weakness after being fed C. maculatum picked by his sister from the roadside 2 hours earlier. He had a rapidly progressive muscular weakness and was intubated for respiratory failure. His symptoms completely resolved within 24 hours of the ingestion. Conium maculatum is a common weed that causes toxicity by its primary toxin, coniine, which stimulates nicotinic receptors and causes a syndrome of rapidly progressive muscle weakness and paralysis. We describe the course of a benign-appearing plant ingestion resulting in respiratory failure.

  17. The calibration of photographic and spectroscopic films. Part 1: Film batch variations of reciprocity failure in IIaO film. Part 2: Thermal and aging effects in relationship to reciprocity failure. P art 3: Shifting of reciprocity failure points as a function of thermal and aging effects

    NASA Technical Reports Server (NTRS)

    Peters, Kevin A.; Atkinson, Pamela F.; Hammond, Ernest C., Jr

    1987-01-01

    Reciprocity failure was examined for IIaO spectroscopic film. Three separate experiments were performed in order to study film batch variations, thermal and aging effects in relationship to reciprocity failure, and shifting of reciprocity failure points as a function of thermal and aging effects. The failure was examined over ranges of time between 5 and 60 seconds. The variation to illuminance was obtained by using thirty neutral density filters. A standard sensitometer device imprinted the wedge pattern on the film as exposure time was subjected to variation. Results indicate that film batch differences, temperature, and aging play an important role in reciprocity failure of IIaO spectroscopic film. A shifting of the failure points was also observed in various batches of film.

  18. Cascading failure in the wireless sensor scale-free networks

    NASA Astrophysics Data System (ADS)

    Liu, Hao-Ran; Dong, Ming-Ru; Yin, Rong-Rong; Han, Li

    2015-05-01

    In the practical wireless sensor networks (WSNs), the cascading failure caused by a failure node has serious impact on the network performance. In this paper, we deeply research the cascading failure of scale-free topology in WSNs. Firstly, a cascading failure model for scale-free topology in WSNs is studied. Through analyzing the influence of the node load on cascading failure, the critical load triggering large-scale cascading failure is obtained. Then based on the critical load, a control method for cascading failure is presented. In addition, the simulation experiments are performed to validate the effectiveness of the control method. The results show that the control method can effectively prevent cascading failure. Project supported by the Natural Science Foundation of Hebei Province, China (Grant No. F2014203239), the Autonomous Research Fund of Young Teacher in Yanshan University (Grant No. 14LGB017) and Yanshan University Doctoral Foundation, China (Grant No. B867).

  19. Episodes of breathlessness: types and patterns - a qualitative study exploring experiences of patients with advanced diseases.

    PubMed

    Simon, Steffen T; Higginson, Irene J; Benalia, Hamid; Gysels, Marjolein; Murtagh, Fliss Em; Spicer, James; Bausewein, Claudia

    2013-06-01

    Despite the high prevalence and impact of episodic breathlessness, information about characteristics and patterns is scarce. To explore the experience of patients with advanced disease suffering from episodic breathlessness, in order to describe types and patterns. Qualitative design using in-depth interviews with patients suffering from advanced stages of chronic heart failure, chronic obstructive pulmonary disease, lung cancer or motor neurone disease. As part of the interviews, patients were asked to draw a graph to illustrate typical patterns of breathlessness episodes. Interviews were tape-recorded, transcribed verbatim and analysed using Framework Analysis. The graphs were grouped according to their patterns. Fifty-one participants (15 chronic heart failure, 14 chronic obstructive pulmonary disease, 13 lung cancer and 9 motor neurone disease) were included (mean age 68.2 years, 30 of 51 men, mean Karnofsky 63.1, mean breathlessness intensity 3.2 of 10). Five different types of episodic breathlessness were described: triggered with normal level of breathlessness, triggered with predictable response (always related to trigger level, e.g. slight exertion causes severe breathlessness), triggered with unpredictable response (not related to trigger level), non-triggered attack-like (quick onset, often severe) and wave-like (triggered or non-triggered, gradual onset). Four patterns of episodic breathlessness could be identified based on the graphs with differences regarding onset and recovery of episodes. These did not correspond with the types of breathlessness described before. Patients with advanced disease experience clearly distinguishable types and patterns of episodic breathlessness. The understanding of these will help clinicians to tailor specific management strategies for patients who suffer from episodes of breathlessness.

  20. Forecasting overhaul or replacement intervals based on estimated system failure intensity

    NASA Astrophysics Data System (ADS)

    Gannon, James M.

    1994-12-01

    System reliability can be expressed in terms of the pattern of failure events over time. Assuming a nonhomogeneous Poisson process and Weibull intensity function for complex repairable system failures, the degree of system deterioration can be approximated. Maximum likelihood estimators (MLE's) for the system Rate of Occurrence of Failure (ROCOF) function are presented. Evaluating the integral of the ROCOF over annual usage intervals yields the expected number of annual system failures. By associating a cost of failure with the expected number of failures, budget and program policy decisions can be made based on expected future maintenance costs. Monte Carlo simulation is used to estimate the range and the distribution of the net present value and internal rate of return of alternative cash flows based on the distributions of the cost inputs and confidence intervals of the MLE's.

  1. Heart Failure as an Aging-Related Phenotype.

    PubMed

    Morita, Hiroyuki; Komuro, Issei

    2018-01-27

    The molecular pathophysiology of heart failure, which is one of the leading causes of mortality, is not yet fully understood. Heart failure can be regarded as a systemic syndrome of aging-related phenotypes. Wnt/β-catenin signaling and the p53 pathway, both of which are key regulators of aging, have been demonstrated to play a critical role in the pathogenesis of heart failure. Circulating C1q was identified as a novel activator of Wnt/β-catenin signaling, promoting systemic aging-related phenotypes including sarcopenia and heart failure. On the other hand, p53 induces the apoptosis of cardiomyocytes in the failing heart. In these molecular mechanisms, the cross-talk between cardiomyocytes and non-cardiomyocytes (e,g,. endothelial cells, fibroblasts, smooth muscle cells, macrophages) deserves mentioning. In this review, we summarize recent advances in the understanding of the molecular pathophysiology underlying heart failure, focusing on Wnt/β-catenin signaling and the p53 pathway.

  2. Analytical Study of different types Of network failure detection and possible remedies

    NASA Astrophysics Data System (ADS)

    Saxena, Shikha; Chandra, Somnath

    2012-07-01

    Faults in a network have various causes,such as the failure of one or more routers, fiber-cuts, failure of physical elements at the optical layer, or extraneous causes like power outages. These faults are usually detected as failures of a set of dependent logical entities and the links affected by the failed components. A reliable control plane plays a crucial role in creating high-level services in the next-generation transport network based on the Generalized Multiprotocol Label Switching (GMPLS) or Automatically Switched Optical Networks (ASON) model. In this paper, approaches to control-plane survivability, based on protection and restoration mechanisms, are examined. Procedures for the control plane state recovery are also discussed, including link and node failure recovery and the concepts of monitoring paths (MPs) and monitoring cycles (MCs) for unique localization of shared risk linked group (SRLG) failures in all-optical networks. An SRLG failure is a failure of multiple links due to a failure of a common resource. MCs (MPs) start and end at same (distinct) monitoring location(s). They are constructed such that any SRLG failure results in the failure of a unique combination of paths and cycles. We derive necessary and sufficient conditions on the set of MCs and MPs needed for localizing an SRLG failure in an arbitrary graph. Procedure of Protection and Restoration of the SRLG failure by backup re-provisioning algorithm have also been discussed.

  3. [Injury pattern caused by aggressive inline skating].

    PubMed

    Hilgert, R E; Besch, L; Behnke, B; Egbers, H-J

    2004-12-01

    In order to evaluate the special injury pattern of aggressive inline skating, a field study was conducted in a local, non-commercial skate park equipped with all the typical features like ramps, halfpipes, gully areas. 66 unselected aggressive inline skaters were randomly enrolled and interviewed concerning their skating habits and their skating injury history. Average age was 15 (10 to 41) years, skating was performed since 2.1 (0.1 to 6) years, as aggressive skating since 1.3 (0.1 to 4) years. Medical treatment in a doctor's practice or in a hospital had been necessary in 66 cases, averaging 1.4 times per skater and year, averaging one injury per 586 hours of aggressive skating. The injury pattern reflected the regions typically injured in fitness skating, too, with a higher percentage of injuries concerning knee, tibia and ankle region. The use of protective devices varied from 41 % (wrist guards) to 94 % (knee pads), with an average of 69 %. Only 32 % of skaters wore all protective devices. As the personal thrill is an important motivation for aggressive skating, safer skating campaigns are quite unlikely to decrease the risk of injury in aggressive skaters.

  4. Antibiotic failure mediated by a resistant subpopulation in Enterobacter cloacae

    PubMed Central

    Band, Victor I.; Crispell, Emily K.; Napier, Brooke A.; Herrera, Carmen M.; Tharp, Greg K.; Vavikolanu, Kranthi; Pohl, Jan; Read, Timothy D.; Bosinger, Steven E.; Trent, M. Stephen; Burd, Eileen M.; Weiss, David S.

    2016-01-01

    Antibiotic resistance is a major public health threat, further complicated by unexplained treatment failures caused by bacteria that appear antibiotic susceptible. We describe an Enterobacter cloacae isolate harbouring a minor subpopulation that is highly resistant to the last-line antibiotic colistin. This subpopulation was distinct from persisters, became predominant in colistin, returned to baseline after colistin removal and was dependent on the histidine kinase PhoQ. During murine infection, but in the absence of colistin, innate immune defences led to an increased frequency of the resistant subpopulation, leading to inefficacy of subsequent colistin therapy. An isolate with a lower-frequency colistin-resistant subpopulation similarly caused treatment failure but was misclassified as susceptible by current diagnostics once cultured outside the host. These data demonstrate the ability of low-frequency bacterial subpopulations to contribute to clinically relevant antibiotic resistance, elucidating an enigmatic cause of antibiotic treatment failure and highlighting the critical need for more sensitive diagnostics. PMID:27572838

  5. A Formal Approach to the Selection by Minimum Error and Pattern Method for Sensor Data Loss Reduction in Unstable Wireless Sensor Network Communications

    PubMed Central

    Kim, Changhwa; Shin, DongHyun

    2017-01-01

    There are wireless networks in which typically communications are unsafe. Most terrestrial wireless sensor networks belong to this category of networks. Another example of an unsafe communication network is an underwater acoustic sensor network (UWASN). In UWASNs in particular, communication failures occur frequently and the failure durations can range from seconds up to a few hours, days, or even weeks. These communication failures can cause data losses significant enough to seriously damage human life or property, depending on their application areas. In this paper, we propose a framework to reduce sensor data loss during communication failures and we present a formal approach to the Selection by Minimum Error and Pattern (SMEP) method that plays the most important role for the reduction in sensor data loss under the proposed framework. The SMEP method is compared with other methods to validate its effectiveness through experiments using real-field sensor data sets. Moreover, based on our experimental results and performance comparisons, the SMEP method has been validated to be better than others in terms of the average sensor data value error rate caused by sensor data loss. PMID:28498312

  6. A Formal Approach to the Selection by Minimum Error and Pattern Method for Sensor Data Loss Reduction in Unstable Wireless Sensor Network Communications.

    PubMed

    Kim, Changhwa; Shin, DongHyun

    2017-05-12

    There are wireless networks in which typically communications are unsafe. Most terrestrial wireless sensor networks belong to this category of networks. Another example of an unsafe communication network is an underwater acoustic sensor network (UWASN). In UWASNs in particular, communication failures occur frequently and the failure durations can range from seconds up to a few hours, days, or even weeks. These communication failures can cause data losses significant enough to seriously damage human life or property, depending on their application areas. In this paper, we propose a framework to reduce sensor data loss during communication failures and we present a formal approach to the Selection by Minimum Error and Pattern (SMEP) method that plays the most important role for the reduction in sensor data loss under the proposed framework. The SMEP method is compared with other methods to validate its effectiveness through experiments using real-field sensor data sets. Moreover, based on our experimental results and performance comparisons, the SMEP method has been validated to be better than others in terms of the average sensor data value error rate caused by sensor data loss.

  7. Dynamics of functional failures and recovery in complex road networks

    NASA Astrophysics Data System (ADS)

    Zhan, Xianyuan; Ukkusuri, Satish V.; Rao, P. Suresh C.

    2017-11-01

    We propose a new framework for modeling the evolution of functional failures and recoveries in complex networks, with traffic congestion on road networks as the case study. Differently from conventional approaches, we transform the evolution of functional states into an equivalent dynamic structural process: dual-vertex splitting and coalescing embedded within the original network structure. The proposed model successfully explains traffic congestion and recovery patterns at the city scale based on high-resolution data from two megacities. Numerical analysis shows that certain network structural attributes can amplify or suppress cascading functional failures. Our approach represents a new general framework to model functional failures and recoveries in flow-based networks and allows understanding of the interplay between structure and function for flow-induced failure propagation and recovery.

  8. [Cardio-renal syndrome: the challenge in heart failure treatment].

    PubMed

    Martins, Hélia; Pedro, Nelson; Castellano, Maria; Monteiro, Pedro; Moura, José Júlio; Providência, Luís A

    2011-01-01

    Heart failure is a chronic and progressive disease that is estimated to affect approximately 20 million people worldwide and is one of the major public health problems. Its prevalence is reaching epidemic levels with about 550,000 new cases diagnosed annually, partly due to increased life expectancy in developed countries. And as it is a systemic disease, it can cause dysfunction in various organs, but especially in the kidney. The renal failure is often associated with heart failure and, when present together, make the treatment more complex and the prognosis is worse. This is the cardio-renal syndrome. The definition of cardio-renal syndrome varies according to the working groups, and there isn't a consensus. The exact cause of deterioration of renal function and the mechanism behind this interaction are complex, multifactorial in nature and not fully known at present. The treatment available is the one used for the treatment of heart failure. It is necessary to maintain the normal function of filtration, secretion and reabsorption in kidney to have a real improvement of the clinical condition of the patient. Patients with higher risk of developing nephropathy and those who have diagnosed renal failure should have prescribed drugs that are handled very carefully. But as in many other clinical situations, there aren't perfect drugs available to treat cardio-renal syndrome and the existing ones may have serious side effects in medium/long term causing the deterioration of renal function and possibly an increased mortality. The treatment is truly challenging in patients with severe fluid overload that is refractory to diuretics. This article aims to present the existing definitions of cardio-renal syndrome, its epidemiology, describe the current knowledge about the pathophysiology and its relationship to therapeutic interventions, some actual strategies and future technologies in an attempt to preserve the kidney, mainly during the decompensation of chronic heart

  9. Obesity Paradox: Comparison of Heart Failure Patients With and Without Comorbid Diabetes.

    PubMed

    Lee, Kyoung Suk; Moser, Debra K; Lennie, Terry A; Pelter, Michele M; Nesbitt, Thomas; Southard, Jeffrey A; Dracup, Kathleen

    2017-03-01

    Diabetes is a common comorbid condition in patients with heart failure and is strongly associated with poor outcomes. Patients with heart failure who have diabetes are more likely to be obese than are those without diabetes. Obesity is positively associated with survival in patients with heart failure, but how comorbid diabetes influences the relationship between obesity and favorable prognosis is unclear. To explore whether the relationship between body mass index and survival differs between patients with heart failure who do or do not have diabetes. The sample consisted of 560 ambulatory patients with heart failure (mean age, 66 years; mean body mass index, 32; diabetes, 41%). The association between body mass index and all-cause mortality was examined by using multivariate Cox proportional hazards regression after adjustments for covariates. In patients without diabetes, higher body mass index was associated with a lower risk for all-cause mortality after adjustments for covariates (hazard ratio, 0.952; 95% CI, 0.909-0.998). In patients with diabetes, body mass index was not predictive of all-cause death after adjustments for covariates. Obesity was a survival benefit in heart failure patients without comorbid diabetes but not in those with comorbid diabetes. The mechanisms underlying the difference in the relationship between obesity and survival due to the presence of diabetes in patients with heart failure need to be elucidated. ©2017 American Association of Critical-Care Nurses.

  10. Acute Respiratory Failure in Cardiac Transplant Recipients.

    PubMed

    Komurcu, Ozgur; Ozdemirkan, Aycan; Camkiran Firat, Aynur; Zeyneloglu, Pinar; Sezgin, Atilla; Pirat, Arash

    2015-11-01

    This study sought to evaluate the incidence, risk factors, and outcomes of acute respiratory failure in cardiac transplant recipients. Cardiac transplant recipients >15 years of age and readmitted to the intensive care unit after cardiac transplant between 2005 and 2015 were included. Thirty-nine patients were included in the final analyses. Patients with acute respiratory failure and without acute respiratory failure were compared. The most frequent causes of readmission were routine intensive care unit follow-up after endomyocardial biopsy, heart failure, sepsis, and pneumonia. Patients who were readmitted to the intensive care unit were further divided into 2 groups based on presence of acute respiratory failure. Patients' ages and body weights did not differ between groups. The groups were not different in terms of comorbidities. The admission sequential organ failure assessment scores were higher in patients with acute respiratory failure. Patients with acute respiratory failure were more likely to use bronchodilators and n-acetylcysteine before readmission. Mean peak inspiratory pressures were higher in patients in acute respiratory failure. Patients with acute respiratory failure developed sepsis more frequently and they were more likely to have hypotension. Patients with acute respiratory failure had higher values of serum creatinine before admission to intensive care unit and in the first day of intensive care unit. Patients with acute respiratory failure had more frequent bilateral opacities on chest radiographs and positive blood and urine cultures. Duration of intensive care unit and hospital stays were not statistically different between groups. Mortality in patients with acute respiratory failure was 76.5% compared with 0% in patients without acute respiratory failure. A significant number of cardiac transplant recipients were readmitted to the intensive care unit. Patients presenting with acute respiratory failure on readmission more frequently

  11. Submandibular gland-sparing radiation therapy for locally advanced oropharyngeal squamous cell carcinoma: patterns of failure and xerostomia outcomes.

    PubMed

    Gensheimer, Michael F; Liao, Jay J; Garden, Adam S; Laramore, George E; Parvathaneni, Upendra

    2014-11-26

    Saliva from submandibular glands (SMG) is necessary to minimize xerostomia. It is unclear whether SMG can be safely spared in patients undergoing bilateral neck radiotherapy for locally advanced oropharyngeal cancer without increasing the risk of marginal recurrence. We evaluated the outcomes of contralateral submandibular gland (cSMG) sparing intensity-modulated radiation therapy (IMRT). All patients with stage III/IV oropharyngeal squamous cell carcinoma treated with bilateral neck IMRT from 2006-2012 at our institution were included. Appropriately selected patients with favorable primary tumor characteristics and no definite contralateral neck disease were treated with cSMG-sparing IMRT. Patterns of failure and xerostomia outcomes were retrospectively analyzed. 114 patients were treated. 89% had stage IV disease and 89% received definitive radiation therapy. 76 patients (67%) received cSMG sparing IMRT. With a median follow-up of 30 months, there were 10 local, 9 regional, and 10 distant recurrences. 2-year overall survival was 86% and 2-year loco-regional control was 87%. In cSMG spared patients, the mean cSMG dose was 30.7 Gy. Late grade 2+ xerostomia was significantly reduced in the cSMG spared group compared to those without SMG sparing (6 months: 23% vs. 72%, 12 months: 6% vs. 41%, 24 months: 3% vs. 36%, all p < 0.0007). There were no peri-SMG marginal recurrences in the cSMG-spared cohort. cSMG sparing IMRT did not increase marginal failures in this series of locally advanced oropharyngeal SCC patients. Xerostomia was significantly reduced in cSMG spared patients.

  12. Reducing unintended pregnancies: a microsimulation of contraceptive switching, discontinuation, and failure patterns in france.

    PubMed

    Diamond-Smith, Nadia G; Moreau, Caroline; Bishai, David M

    2014-12-01

    Although the rate of contraceptive use in France is high, more than one-third of pregnancies are unintended. We built a dynamic microsimulation model that applies data from the French COCON study on method switching, discontinuation, and failure rates to a hypothetical population of 20,000 women, followed for five years. We use the model to estimate the adjustment factor needed to make the survey data fit the demographic profile of France by adjusting for underreporting of contraceptive nonuse and abortion. We then test three behavior-change scenarios that could reduce unintended pregnancies: decreasing method failure, increasing time using effective methods, and increasing switching from less effective to more effective methods. Our model suggests that decreasing method failure is the most effective means of reducing unintended pregnancies, but we found that all of the scenarios reduced unintended pregnancies by at least 25 percent. Dynamic microsimulations may have great potential in reproductive health research and prove useful for policymakers. © 2014 The Population Council, Inc.