An Empirical Fracture Control Model for Dense-Phase CO2 Carrying Pipelines

2020 ◽  
Author(s):  
Guillaume Michal ◽  
Erling Østby ◽  
Bradley J. Davis ◽  
Sigbjørn Røneid ◽  
Cheng Lu
Keyword(s):  
Ductile Fracture ◽  
Empirical Model ◽  
Published Data ◽  
Dense Phase ◽  
Current Standard ◽  
Data Points ◽  
Curve Method ◽  
Fracture Control ◽  
Definition Of ◽  
Co2 Transportation

Abstract The control of a running ductile fracture in dense-phase CO2 carrying pipelines requires noticeably better fracture resistance than that typically required for the transport of lean or rich natural gas. The long saturation plateau of the decompression sustains a significant driving force at low fracture velocities. Since 2012, at least four independent projects published data to better understand the applicability of the Battelle Two-Curve Method for CO2 transportation, provide insight on minimum toughness requirements and margins of safety. Nine full-scale propagation tests were executed across these projects. About 50 pipes had interactions with a running ductile fracture, 33 pipes supported the propagation of the fracture over their entire length, the other 17 pipes stopped the fracture. The original BTCM is not considered applicable with dense-phase CO2. Despite the actual decompression velocity’s saturation plateau decreasing with velocity, and despite the pressure at the crack tip being typically 8 bar lower than predicted, the model can be significantly non-conservative. Correction factors on toughness and arrest pressure are required. An empirical model for prediction of the minimum required toughness is proposed. It is supported by the data from the four aforementioned projects. The details and the limitations of the database are presented. The arrest boundary is expressed graphically in the frame commonly used to present the NG18 arrest pressure boundary. A discussion on the location of the experimental data points relative to the arrest-propagation boundary is given. It supports the definition of three regions of interest: a region of likely propagation, a region of likely arrest, and a transition region between these two, where the boundary resides. All current standard and recommended practices have seemingly similar gaps with respect to the control of a running ductile fracture. The empirical model brings along a set of recommendations and requirements to consider in the context of dense-phase CO2 applications.

scholarly journals P007: A comparative analysis of qSOFA, SIRS and Early Warning Scores Criteria to identify sepsis in the prehospital setting

CJEM ◽  
2017 ◽  
Vol 19 (S1) ◽  
pp. S79-S80 ◽  
Author(s):  
S. AlQahtani ◽  
P. Menzies ◽  
B. Bigham ◽  
M. Welsford
Keyword(s):  
Severe Sepsis ◽  
Screening Tool ◽  
Early Recognition ◽  
Capture Rate ◽  
Data Capture ◽  
Prehospital Setting ◽  
Life Saving ◽  
Data Points ◽  
And Performance ◽  
Definition Of

Introduction: Early recognition of sepsis is key in delivering timely life-saving interventions. The role of paramedics in recognition of these patients is understudied. It is not known if the usual prehospital information gathered is sufficient for severe sepsis recognition. We sought to: 1) evaluate the paramedic medical records (PMRs) of severe sepsis patients to describe epidemiologic characteristics; 2) determine which severe sepsis recognition and prediction scores are routinely captured by paramedics; and 3) determine how these scores perform in the prehospital setting. Methods: We performed a retrospective review of patients ≥18 years who met the definition of severe sepsis in one of two urban Emergency Departments (ED) and had arrived by ambulance over an eighteen-month period. PMRs were evaluated for demographic, physiologic and clinical variables. The information was entered into a database, which auto-filled a tool that determined SIRS criteria, shock index, prehospital critical illness score, NEWS, MEWS, HEWS, MEDS and qSOFA. Descriptive statistics were calculated. Results: We enrolled 298 eligible sepsis patients: male 50.3%, mean age 73 years, and mean prehospital transportation time 30 minutes. Hospital mortality was 37.5%. PMRs captured initial: respiratory rate 88.6%, heart rate 90%, systolic blood pressure 83.2%, oxygen saturation 59%, temperature 18.7%, and Glasgow Coma Scale 89%. Although complete MEWS and HEWS data capture rate was <17%, 98% and 68% patients met the cut-point defining “critically-unwell” (MEWS ≥3) and “trigger score” (HEWS ≥5), respectively. The qSOFA criteria were completely captured in 82% of patients; however, it was positive in only 36%. It performed similarly to SIRS, which was positive in only 34% of patients. The other scores were interim in having complete data captured and performance for sepsis recognition. Conclusion: Patients transported by ambulance with severe sepsis have high mortality. Despite the variable rate of data capture, PMRs include sufficient data points to recognize prehospital severe sepsis. A validated screening tool that can be applied by paramedics is still lacking. qSOFA does not appear to be sensitive enough to be used as a prehospital screening tool for deadly sepsis, however, MEWS or HEWS may be appropriate to evaluate in a large prospective study.

scholarly journals Archaeointensity results spanning the past 6 kiloyears from eastern China and implications for extreme behaviors of the geomagnetic field

2016 ◽  
Vol 114 (1) ◽  
pp. 39-44 ◽  
Author(s):  
Shuhui Cai ◽  
Guiyun Jin ◽  
Lisa Tauxe ◽  
Chenglong Deng ◽  
Huafeng Qin ◽  
...  
Keyword(s):  
Geomagnetic Field ◽  
Dipole Moments ◽  
Eastern China ◽  
Published Data ◽  
Reference Curve ◽  
The Holocene ◽  
The Past ◽  
Deep Interior ◽  
Archaeomagnetic Dating ◽  
Data Points

Variations of the Earth’s geomagnetic field during the Holocene are important for understanding centennial to millennial-scale processes of the Earth’s deep interior and have enormous potential implications for chronological correlations (e.g., comparisons between different sedimentary recording sequences, archaeomagnetic dating). Here, we present 21 robust archaeointensity data points from eastern China spanning the past ∼6 kyr. These results add significantly to the published data both regionally and globally. Taking together, we establish an archaeointensity reference curve for Eastern Asia, which can be used for archaeomagnetic dating in this region. Virtual axial dipole moments (VADMs) of the data range from a Holocene-wide low of ∼27 to “spike” values of ∼166 ZAm2(Z: 1021). The results, in conjunction with our recently published data, confirm the existence of a decrease in paleointensity (DIP) in China around ∼2200 BCE. These low intensities are the lowest ever found for the Holocene and have not been reported outside of China. We also report a spike intensity of 165.8 ± 6.0 ZAm2at ∼1300 BCE (±300 y), which is either a prelude to or the same event (within age uncertainties) as spikes first reported in the Levant.

Oligodendroglial tumours

2017 ◽  
Author(s):  
Wolfgang Wick ◽  
Colin Watts ◽  
Minesh P. Mehta
Keyword(s):  
Overall Survival ◽  
Randomized Trials ◽  
Current Standard ◽  
Future Directions ◽  
Imaging Parameters ◽  
Term Evaluation ◽  
Molecular Information ◽  
Translational Studies ◽  
Definition Of

Concepts of diagnosis and treatment of oligodendroglial tumours have changed through clinical and translational studies over recent years. Diagnosis is now based on histopathological and integrated molecular information. The latter includes mutations in isocitrate dehydrogenase and the co-deletion of 1p/19q in the tumour tissue. In parallel, the long-term evaluation of large randomized trials performed in Europe and North America led to the current standard of a more aggressive chemoradiation regimen with procarbazine, CCNU (lomustine), and vincristine to optimize progression-free and overall survival. The future directions are delineated, which are aiming at further definition of prognostic and predictive subgroups, based on clinical, molecular, and imaging parameters, integrating immunotherapeutic concepts, as well as a closer look at patient-centred outcomes in upcoming trials.

scholarly journals Lower Permian brachiopods from Oman: their potential as climatic proxies

2007 ◽  
Vol 98 (3-4) ◽  
pp. 327-344 ◽  
Author(s):  
L. Angiolini ◽  
D. P. F. Darbyshire ◽  
M. H. Stephenson ◽  
M. J. Leng ◽  
T. S. Brewer ◽  
...  
Keyword(s):  
Isotope Composition ◽  
Isotopic Analysis ◽  
Lower Permian ◽  
Published Data ◽  
Sr Isotope ◽  
Marine Sedimentation ◽  
Ice Accumulation ◽  
Secondary Layer ◽  
Data Points ◽  
Few Data

ABSTRACTThe Lower Permian of the Haushi basin, Interior Oman (Al Khlata Formation to Saiwan Formation/lower Gharif member) records climate change from glaciation, through marine sedimentation in the Haushi sea, to subtropical desert. To investigate the palaeoclimatic evolution of the Haushi Sea we used O, C, and Sr isotopes from 31 brachiopod shells of eight species collected bed by bed within the type-section of the Saiwan Formation. We assessed diagenesis by scanning electron microscopy of ultrastructure, cathodoluminescence, and geochemistry, and rejected fifteen shells not meeting specific preservation criteria. Spiriferids and spiriferinids show better preservation of the fibrous secondary layer than do orthotetids and productids and are therefore more suitable for isotopic analysis. δ18O of −3·7 to −3·1℅ from brachiopods at the base of the Saiwan Formation are probably related to glacial meltwater. Above this, an increase in δ18O may indicate ice accumulation elsewhere in Gondwana or more probably that the Haushi sea was an evaporating embayment of the Neotethys Ocean. δ13C varies little and is within the range of published data: its trend towards heavier values is consistent with increasing aridity and oligotrophy. Saiwan Sr isotope signatures are less radiogenic than those of the Sakmarian LOWESS seawater curve, which is based on extrapolation between few data points. In the scenario of evaporation in a restricted Haushi basin, the variation in Sr isotope composition may reflect a fluvial component.

Similar Incidence of Typhlitis in Patients Receiving Various Doses of Daunorubicin or Idarubicin As Induction for Acute Myeloid Leukemia

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 3725-3725
Author(s):  
Amanda N Seddon ◽  
Angela G Michael ◽  
Nelly G. Adel ◽  
Martin S. Tallman ◽  
Oguz Akin ◽  
...  
Keyword(s):  
Clinical Symptoms ◽  
Conflicts Of Interest ◽  
Standard Of Care ◽  
Adult Patients ◽  
Cell Transplant ◽  
Current Standard ◽  
Ileocecal Region ◽  
Concomitant Infection ◽  
Potential Factors ◽  
Definition Of

Abstract Background: The current standard of care for the treatment of patients with newly diagnosed AML is an anthracycline plus cytarabine. Both anthracyclines and cytarabine have been associated with the development of typhlitis, a serious adverse event characterized by inflammation of the bowel wall in patients with profound neutropenia, diagnosed via abdominal CT imaging and clinical symptoms. Given the paucity of available data, the aim of our study was to determine the incidence of typhlitis among AML patients receiving induction with either idarubicin 12 mg/m2 (IDA), daunorubicin 60 mg/m2 (DNA60), or daunorubicin 90 mg/m2 (DNA90). Methods: Adult patients with AML or MDS receiving either daunorubicin or idarubicin along with cytarabine as part of their induction regimen between 1/1/2009 and 6/30/2013 were included. A definition of typhlitis required CT confirmation of inflammation of the cecum, according to CTCAE version 4.03 along with clinical symptoms. Two radiologists (OA, JC) blinded to the treatment and outcomes independently reviewed CT scans. Two additional definitions including inflammation of the ileocecal region only and enterocolitis were also evaluated. All statistical analyses were performed on SAS software version 9.3. P values were calculated using Fisher Exact and Wilcoxon tests. Inter-rater reliability was assessed with Cohen’s Kappa. Results: Baseline characteristics were similar among the 3 treatment groups with the exception of age. The median age was lower in the DNA90 arm (79 years, 74 years, and 49 years in the IDA group, DNA60 group, and DNA90 group, respectively). A pre-existing GI disorder was reported in 24.1% IDA, 25.7% DNA60, and 22.4% DNA90 patients. Of the 202 total patients, the two radiologists determined that 40 (20%) and 38 (19%) developed typhlitis, based on the predefined standard. Tables 1 and 2 illustrate the relationship between treatment arm and associated incidence of typhlitis. The incidence in each treatment group did not statistically differ (p=0.23 and p=0.29). When the definition was broadened to include ileocecal region and enterocolitis, the incidence increased (Tables 1 and 2). The inter-reliability ratings of the 2 radiologists’ evaluations for each definition indicated substantial agreement (0.803 cecum, 0.834 ileocecal region only, and 0.752 enterocolitis). Neither the anthracycline chosen, nor the dose had a statistically significant impact on the incidence of typhlitis. Of all patient and treatment specific risk factors assessed for association with development of typhlitis (pre-existing GI disorder, rheumatologic disorder or cancer, prior RT, stem cell transplant or anthracycline exposure, cytarabine regimen or AML risk group), none were found to be statistically significant. In patients that developed typhlitis, approximately 56% and 51% had a concurrent documented infection around the typhlitis episode (Tables 1-2). Conclusion: To our knowledge, this is the first study to compare the incidence of typhlitis in adult patients receiving idarubicin or daunorubicin for the treatment of AML. While the cumulative incidence of typhlitis was higher than in published literature, the incidence was similar irrespective of the anthracycline chosen or dose. Of the potential factors that may have contributed to the development of typhlitis, none were significantly associated with typhlitis. All patients were managed conservatively with broad-spectrum antibiotics. A more definitive definition of typhlitis may help clinicians identify affected patients sooner and choose appropriate targeted therapy. Abstract 3725. Table 1. Association of treatment to Radiologist 1-rated typhlitis Enterocolitis Ileocecal region only Cecum No Yes P No Yes P No Yes P Treatment 0.52 0.68 0.23 DNA60 58 (78%) 16 (22%) 58 (78%) 16 (22%) 61 (82%) 13 (18%) DNA90 34 (69%) 15 (31%) 35 (71%) 14 (29%) 35 (71%) 14 (29%) IDA 58 (73%) 21 (27%) 60 (76%) 19 (24%) 66 (84%) 13 (16%) Concomitant infection Yes 11 (26%) 32 (74%) 13 (30%) 30 (70%) 19 (44%) 24 (56%) Abstract 3725. Table 2. Association of treatment to Radiologist 2-rated typhlitis Enterocolitis Ileocecal region only Cecum No Yes P No Yes P No Yes P Treatment 0.86 0.98 0.29 DNA60 57 (77%) 17 (23%) 57 (77%) 17 (23%) 62 (84%) 12(16%) DNA90 36 (73%) 13 (27%) 37 (76%) 12 (24%) 36 (73%) 13 (27%) IDA 58 (73%) 21 (27%) 61 (77%) 18 (23%) 66 (84%) 13 (16%) Concomitant infection Yes 11 (26%) 32 (74%) 13 (30%) 30 (70%) 21 (49%) 22 (51%) Disclosures No relevant conflicts of interest to declare.

scholarly journals Temporal Analysis Of Temperature Variability In Pakistan Using The Method Of Empirical Mode Decomposition

2021 ◽  
Vol 10 (3) ◽  
pp. 1632-1638
Keyword(s):  
Neural Networks ◽  
Empirical Model ◽  
Significant Variation ◽  
Moving Average ◽  
Temporal Analysis ◽  
Average Temperature ◽  
Temperature And Precipitation ◽  
Mode Decomposition ◽  
Data Points ◽  
Auto Regressive

Pakistan is a country with altitudes that ranges from sea level to the world’s second-highest mountain peak in theworld. This distinctive characteristic renders a significant variation in the countries’ climate, for instance, temperature differences and spatial distribution of rainfall. These variations in the corresponding temperature and precipitation are best described and predicted by well-defined classifications of climatic variables and their corresponding spatial distributions across Pakistan. This paper demonstrates the techniques that allow us to predict the average temperature of Pakistan using empirical model decomposing with auto regressive integrated moving average (EMD-ARIMA) and empirical model decomposing with auto regressive integrated moving average with neural networks (EMD-ARIMA–NN) models. This research was applied to a lengthy series of average monthly temperature (report in oC) of Pakistan from January 1901 to December 2016 with 1392 data points. The precision of these models is checked with the avail of statistical analysis and error tests. Comparative analysis shows that the empirical model decomposing with auto regressive integrated moving average with neural networks has a more preponderant forecast

scholarly journals Clinical challenges with hypervirulent Klebsiella pneumoniae (hvKP) in China

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Yanzhu Chen ◽  
Yi Chen
Keyword(s):  
Antimicrobial Resistance ◽  
Klebsiella Pneumoniae ◽  
Published Data ◽  
Clinical Microbiology Laboratory ◽  
Consensus Definition ◽  
Antibiotic Resistant ◽  
Resistance Determinants ◽  
The Past ◽  
Resistant Strains ◽  
Definition Of

AbstractHypervirulent Klebsiella pneumoniae (hvKp) is an evolving pathotype with higher virulence than classical K. pneumoniae (cKp) and is characterized by community-acquired, multiple sites of infections and young and healthy hosts. hvKP infections were primarily found in East Asia and have been increasingly reported worldwide over the past few decades. To better understand the clinical challenges faced by China with hvKP, this review will provide a summary and discussion focused on recognizing hvKP strains and prevalence of antibiotic-resistant hypervirulent strains in China and the mechanisms of acquiring antimicrobial resistance. Compared with cKP, hvKP is likely to cause serious disseminated infections, leading to a higher mortality. However, sensitive and specific clinical microbiology laboratory tests are still not available. Given the limited published data due to the clinical difficulty in differentiating hvKP from cKP, extrapolation of the previous data may not be applicable for the management of hvKP. A consensus definition of hvKP is needed. Furthermore, an increasing number of reports have described hvKp strains with antimicrobial resistance acquisition, increasing the challenges for management of hvKP. China, as an epidemic country, is also facing these challenges. Quite a number of studies from China have reported antibiotic-resistant hvKP strains, including extended-spectrum β-lactamase (ESBL), and carbapenem-, tigecycline-, and colistin-resistant strains. hvKP infections, especially those of antimicrobial-resistant strains, pose to be a great threat for public health in China. Therefore, an immediate response to recognize the hypervirulent strains and provide optimal treatments, especially those with resistance determinants, is an urgent priority for China.

scholarly journals Transmission of SARS-CoV-2 associated with aircraft travel: a systematic review (Version 1)

2021 ◽  
Author(s):  
Elena Cecilia Rosca ◽  
Carl Heneghan ◽  
Elizabeth A Spencer ◽  
Jon Brassey ◽  
Annette Pluddemann ◽  
...  
Keyword(s):  
Virus Transmission ◽  
Air Travel ◽  
Policy Implications ◽  
Current Evidence ◽  
Published Data ◽  
Virus Infections ◽  
Quality Of Reporting ◽  
Definition Of ◽  
Respiratory Virus Infections

Background: Air travel may be associated with the spread of viruses via infected passengers and potentially through in-flight transmission. Given the novelty of the SARS-CoV-2 virus, transmission associated with air travel is based on what is known about the dynamics of transmission of other respiratory virus infections, especially those due to other coronaviruses and influenza. Our objective was to provide a rapid summary and evaluation of relevant data on the transmission of SARS-CoV-2 aboard aircraft, report important policy implications, and highlight research gaps requiring urgent attention. Methods: This review is part of an Open Evidence Review on Transmission Dynamics of SARS-CoV-2. We searched LitCovid, medRxiv, Google Scholar, and the WHO Covid-19 database from 1 February 2020 to 27 January 2021 and included studies on the transmission of SARS-CoV-2 aboard aircraft. We assessed study quality based on five criteria and reported important findings. Results: We included 18 studies on in-flight transmission of SARS-CoV-2, representing 130 unique flights and two studies on wastewater from aircraft. The overall quality of reporting was low. Two wastewater studies reported PCR-positive SARS-CoV-2 samples, but with relatively high Cycle threshold values ranging from 36 to 40. The definition of an index case was very heterogeneous across the studies. The proportion of contacts traced ranged from 0.68% to 100%. In total, the authors successfully traced 2800/19729 passengers, 140/180 crew members, and 8/8 medical staff. Altogether, 273 index cases were reported, with 64 secondary cases. No secondary cases were reported in three studies, each investigating one flight. The secondary attack rate among the studies that followed up >80% of the passengers and crew (including data on 10 flights) varied between 0% and 8.2%. The included studies reported on the possibility of SARS-CoV-2 transmission from asymptomatic, pre-symptomatic, and symptomatic individuals. Viral cultures were performed in two studies, with 10 positive results reported. Genomic sequencing and phylogenetic analysis were performed in individuals from four flights, with the completeness of genomic similarity ranging from 81-100%. Conclusion: Current evidence suggests that SARS-CoV-2 can be transmitted during aircraft travel, but the published data do not permit any conclusive assessment of the likelihood and extent. Furthermore, the quality of evidence from most published studies is low. The variation in study design and methodology restricts the comparison of findings across studies. Standardized guidelines for conducting and reporting future studies of transmission on aircrafts should be developed.

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