Fracability evaluation of lacustrine shale by integrating brittleness and fracture toughness

2019 ◽  
Vol 7 (2) ◽  
pp. T363-T372
Author(s):  
Cheng Huang ◽  
Chao Yang ◽  
Feng Shen
Keyword(s):  
Fracture Toughness ◽  
Plastic Strain ◽  
Strain Energy ◽  
Evaluation Method ◽  
Peak Stress ◽  
Brittleness Index ◽  
Before And After ◽  
Lacustrine Shale ◽  
The Difference ◽  
The Impact

Rock brittleness and fracture toughness are important parameters for evaluating rock fracability. The stress-strain curves indicate that the lacustrine shale is strongly brittle. Brittle failure occurs rapidly when the stress of the lacustrine shale reaches its peak value. In addition, the lacustrine shale has different plastic strains before and after peak stress; this can relax the stress concentration of the crack tips. Therefore, the plastic strain that occurs before and after the peak stress can cause decreasing brittleness, which can be used to distinguish the brittleness and fracability in the formation of the lacustrine shale clearly. Moreover, this further enlarges the difference in the brittleness index. Based on the influence of plastic strain on brittleness, we have developed a new brittleness evaluation method that uses the ratio of linear elastic strain energy to the total strain energy before complete rock failure, which can indicate the difference of the lacustrine shale clearly. Fracture toughness is another important parameter that impacts the fracture extension and influences fracability. Based on the impact of brittleness and fracture toughness on the fracability, we have developed a new fracability evaluation method. The brittleness index increases with increases in the quartz content, and it decreases with increases in the albite feldspar and calcite contents. The fracture toughness decreases with increases in the quartz and clay contents, and it increases with increases in the siderite content. In addition, we established an empirical formula that can evaluate the brittleness index and the fracture toughness using mineral contents obtained from elemental logging. Using the new fracability evaluation method to optimize the fracturing stage, the preliminary field test indicates that the new approach was effective in the lacustrine shale formation.

scholarly journals The Impact of the COVID-19 Pandemic on User Experience with Online Education Platforms in China

2020 ◽  
Vol 12 (18) ◽  
pp. 7329 ◽  
Author(s):  
Tinggui Chen ◽  
Lijuan Peng ◽  
Bailu Jing ◽  
Chenyue Wu ◽  
Jianjun Yang ◽  
...  
Keyword(s):  
Online Education ◽  
User Experience ◽  
Evaluation Method ◽  
Comprehensive Evaluation ◽  
Relevant Literature ◽  
Evaluation Index System ◽  
Video Information ◽  
Before And After ◽  
The Difference ◽  
The Impact

During the COVID-19 pandemic, social education has shifted from face to face to online in order to avoid large gatherings and crowds for blocking the transmission of the virus. To analyze the impact of virus on user experience and deeply retrieve users’ requirements, this paper constructs a reasonable evaluation index system through obtaining user reviews about seven major online education platforms before and after the outbreak of COVID-19, and by combining the emotional analysis, hot mining technology, as well as relevant literature. At the same time, the variation coefficient method is chosen to weigh each index based on the difference of index values. Furthermore, this paper adopts the comprehensive evaluation method to analyze user experience before and after the outbreak of COVID-19, and finally finds out the change of users’ concerns regarding the online education platform. In terms of access speed, reliability, timely transmission technology of video information, course management, communication and interaction, and learning and technical support, this paper explores the supporting abilities and response levels of online education platforms during COVID-19, and puts forward corresponding measures to improve how these platforms function.

scholarly journals 216. Are Automatic Antimicrobial Stop Orders an Effective Stewardship Tool for Urinary Tract and Intra-Abdominal Infections?

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S110-S110
Author(s):  
Christina Maguire ◽  
Dusten T Rose ◽  
Theresa Jaso
Keyword(s):  
Urinary Tract ◽  
Antimicrobial Therapy ◽  
Source Control ◽  
Clostridioides Difficile ◽  
Days Of Therapy ◽  
Before And After ◽  
The Difference ◽  
Tract Infections ◽  
Length Of Therapy ◽  
The Impact

Abstract Background Automatic antimicrobial stop orders (ASOs) are a stewardship initiative used to decrease days of therapy, prevent resistance, and reduce drug costs. Limited evidence outside of the perioperative setting exists on the effects of ASOs on broad spectrum antimicrobial use, discharge prescription duration, and effects of missed doses. This study aims to evaluate the impact of an ASO policy across a health system of adult academic and community hospitals for treatment of intra-abdominal (IAI) and urinary tract infections (UTI). ASO Outcome Definitions ASO Outcomes Methods This multicenter retrospective cohort study compared patients with IAI and UTI treated before and after implementation of an ASO. Patients over the age of 18 with a diagnosis of UTI or IAI and 48 hours of intravenous (IV) antimicrobial administration were included. Patients unable to achieve IAI source control within 48 hours or those with a concomitant infection were excluded. The primary outcome was the difference in sum length of antimicrobial therapy (LOT). Secondary endpoints include length and days of antimicrobial therapy (DOT) at multiple timepoints, all cause in hospital mortality and readmission, and adverse events such as rates of Clostridioides difficile infection. Outcomes were also evaluated by type of infection, hospital site, and presence of infectious diseases (ID) pharmacist on site. Results This study included 119 patients in the pre-ASO group and 121 patients in the post-ASO group. ASO shortened sum length of therapy (LOT) (12 days vs 11 days respectively; p=0.0364) and sum DOT (15 days vs 12 days respectively; p=0.022). This finding appears to be driven by a decrease in outpatient LOT (p=0.0017) and outpatient DOT (p=0.0034). Conversely, ASO extended empiric IV LOT (p=0.005). All other secondary outcomes were not significant. Ten patients missed doses of antimicrobials due to ASO. Subgroup analyses suggested that one hospital may have influenced outcomes and reduction in LOT was observed primarily in sites without an ID pharmacist on site (p=0.018). Conclusion While implementation of ASO decreases sum length of inpatient and outpatient therapy, it may not influence inpatient length of therapy alone. Moreover, ASOs prolong use of empiric intravenous therapy. Hospitals without an ID pharmacist may benefit most from ASO protocols. Disclosures All Authors: No reported disclosures

scholarly journals The impact of a ‘milking the COW’ campaign in a regional hospital in Singapore

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Surinder Kaur M. S. Pada ◽  
Poh Lishi ◽  
Kim Sim Ng ◽  
Sarathamani Rethenam ◽  
Lilibeth Silagan Alenton ◽  
...  
Keyword(s):  
Hand Hygiene ◽  
Pathogenic Bacteria ◽  
Mixed Model ◽  
Mixed Model Analysis ◽  
Colony Forming Units ◽  
Skin Flora ◽  
Before And After ◽  
The Difference ◽  
And Control ◽  
The Impact

Abstract Background Computerisation of various processes in hospitals and reliance on electronic devices raises the concern of contamination of these devices from the patient environment. We undertook this study to determine if an attached hand hygiene device that unlocks the screen of a computer on wheels (COW) on usage can be effective in decreasing the microbiological burden on computer keyboards. Methods An electronic hand sanitizer was integrated onto the COW. A prospective cohort study with a crossover design involving 2 control and 2 intervention wards was used. The study end point was the number of colony forming units found on the keyboards. Bacteria were classified into 4 main groups; pathogenic, skin flora, from the environment or those thought to be commensals in healthy individuals. We then used a mixed effects model for the statistical analysis to determine if there were any differences before and after the intervention. Results Thirty-nine keyboards were swabbed at baseline, day 7 and 14, with 234 keyboards cultured, colony forming units (CFUs) counted and organisms isolated. By mixed model analysis, the difference of mean bacteria count between intervention and control for week 1 was 32.74 (− 32.74, CI − 94.29 to 28.75, p = 0.29), for week 2 by 155.86 (− 155.86, CI − 227.45 to − 83.53, p < 0.0001), and after the 2-week period by 157.04 (− 157.04, CI − 231.53 to − 82.67, p < 0.0001). In the sub-analysis, there were significant differences of pathogenic bacteria counts for the Intervention as compared to the Control in contrast with commensal counts. Conclusion A hand hygiene device attached to a COW may be effective in decreasing the microbiological burden on computer keyboards.

scholarly journals Assessment of the Construction of a Climate Resilient City: An Empirical Study Based on the Difference in Differences Model

2021 ◽  
Vol 18 (4) ◽  
pp. 2082
Author(s):  
Zifeng Liang
Keyword(s):  
Significant Contribution ◽  
Evaluation Method ◽  
Regional Climate ◽  
Chinese Government ◽  
Infrastructure Development ◽  
Grey System ◽  
Difference In Differences ◽  
Climate Resilience ◽  
The Difference ◽  
The Impact

Facing climate risks has become a common problem for mankind and a topic of great importance for the Chinese government. To thoroughly implement the overall requirements for the construction of an ecological civilization and effectively improve the capacity of cities to adapt to climate change, China launched the pilot construction of “Climate Resilient Cities” in 2017. In this paper, 16 prefecture level cities in Anhui Province of China were selected as the research objects, and the multi-level grey system evaluation method was used to measure the climate resilience of these regions. We used the difference in differences method to evaluate the effect of the pilot policy of “Climate Resilient Cities.” The pilot policies of the “Climate Resilient Cities” showed a significant contribution to the regional climate resilience, and, after isolating the impact of other factors on the regional climate resilience, the pilot policies of the “Climate Resilient Cities” increased the climate resilience of the pilot cities by four percentage points. The pilot policies of the “Climate Resilient Cities” had a significant contribution to the urban infrastructure development and ecological space optimization, as well as non-significant impacts to the urban water security, emergency management capacity-building, and science and technology innovation initiatives.

Impact of Louisiana’s HPV Vaccine Awareness Policy on HPV Vaccination Among 13- to 17-Year-Old Females

2017 ◽  
Vol 44 (4) ◽  
pp. 548-558 ◽  
Author(s):  
Dudith Pierre-Victor ◽  
Mary Jo Trepka ◽  
Timothy F. Page ◽  
Tan Li ◽  
Dionne P. Stephens ◽  
...  
Keyword(s):  
Hpv Vaccine ◽  
Hpv Vaccination ◽  
Female Adolescents ◽  
Physician Recommendation ◽  
Vaccination Rates ◽  
National Immunization ◽  
Before And After ◽  
The Difference ◽  
Vaccine Information ◽  
The Impact

The Advisory Committee on Immunization Practices recommends routine human papillomavirus (HPV) immunization for 11- to 12-year-old adolescents. In 2008, Louisiana required the school boards to distribute HPV vaccine information to parents or guardian of students in Grades 6 to 12. This article investigates the impact of this policy on HPV vaccination among 13- to 17-year-old female adolescents using National Immunization Survey-Teen (NIS-Teen) data. Drawing on the data from the 2008 to 2012 NIS-Teen, we compared the difference in proportions of females who have been vaccinated before and after the policy. Using difference-indifference estimation, we explored the change in vaccination rates before and after the policy implementation in Louisiana compared with Alabama and Mississippi, two states that did not have such a policy in place. The difference-in-differences estimates for HPV vaccination were not significant. Physician recommendation for HPV vaccination was significantly associated with vaccination among females in Louisiana and Alabama (adjusted odds ratio [aOR] = 7.74; 95% confidence interval [CI; 5.22, 11.5]), and for those in Louisiana and Mississippi (aOR = 7.05; 95% CI [4.6, 10.5]). Compared to the proportion of female adolescents who had received physician recommendation in Alabama or Mississippi, the proportion in Louisiana did not increase significantly in the postpolicy period. HPV vaccination rates did not increase significantly in Louisiana compared to Alabama or Mississippi following the implementation of the policy. Despite Louisiana’s policy, physician recommendation remains the key determinant of HPV vaccination. HPV vaccine awareness does not necessarily result in HPV vaccination.

A Case–Control Study Evaluating the Impact of Dedicated Palliative Care Training on Critical Care Interventions at the end of Life

2021 ◽  
pp. 082585972110374
Author(s):  
Jee Y. You ◽  
Lie D. Ligasaputri ◽  
Adarsh Katamreddy ◽  
Kiran Para ◽  
Elizabeth Kavanagh ◽  
...  
Keyword(s):  
Palliative Care ◽  
Critical Care ◽  
High Risk ◽  
End Of Life ◽  
Poor Prognosis ◽  
Medical Interventions ◽  
Risk Of Death ◽  
Before And After ◽  
The Difference ◽  
The Impact

Many patients admitted to intensive care units (ICUs) are at high risk of dying. We hypothesize that focused training sessions for ICU providers by palliative care (PC) certified experts will decrease aggressive medical interventions at the end of life. We designed and implemented a 6-session PC training program in communication skills and goals of care (GOC) meetings for ICU teams, including house staff, critical care fellows, and attendings. We then reviewed charts of ICU patients treated before and after the intervention. Forty-nine of 177 (28%) and 63 of 173 (38%) patients were identified to be at high risk of death in the pre- and postintervention periods, respectively, and were included based on the study criteria. Inpatient mortality (45% vs 33%; P = .24) and need for mechanical ventilation (59% vs 44%, P = .13) were slightly higher in the preintervention population, but the difference was not statistically significant. The proportion of patients in whom the decision not to initiate renal replacement therapy was made because of poor prognosis was significantly higher in the postintervention population (14% vs 67%, P = .05). There was a nonstatistically significant trend toward earlier GOC discussions (median time from ICU admission to GOC 4 vs 3 days) and fewer critical care interventions such as tracheostomies (17% vs 4%, P = .19). Our study demonstrates that directed PC training of ICU teams has a potential to reduce end of life critical care interventions in patients with a poor prognosis.

scholarly journals The impact of COVID 19 pandemic on pattern of cancer mortality in Najran, Saudi Arabia: a single-cancer center experience

2021 ◽  
Author(s):  
Ahmed M Badheeb ◽  
Mohamed A Badheeb ◽  
Hamdi A Alhakimi
Keyword(s):  
Hepatocellular Carcinoma ◽  
Saudi Arabia ◽  
Cancer Treatment ◽  
Cancer Patients ◽  
Cancer Mortality ◽  
Cancer Center ◽  
Anti Cancer ◽  
Before And After ◽  
The Difference ◽  
The Impact

Abstract Background: The aim of this paper is to compare the patterns and determinants of cancer mortality in Najran region before and after the COVID-19 epidemics. The association between cancer mortality and each of age, sex, site of cancer, stage, and the 30-days survival rate after the last dose of chemotherapy were assessed.Materials & Methods: Adult cancer patients who died of cancer in King Khalid Hospital in Najran Saudi Arabia, were included in this retrospective observational study. We compared mortality patterns in a period of 6 months in 2020 (March to August) with the corresponding period of 2019.Results: 50 dead adult cancer patients were included, 24 in 2019 and 26 in 2020. Among them, 21% vs 42% were younger than 65 years of age; 61% vs 62% were males, for the years 2019 & 2020 respectively. The top three killers in 2019 were colorectal, gastro-esophageal cancers, and hepatocellular carcinoma, while in 2020 were colorectal, hepatocellular carcinoma, and lymphomas. About 16.7% of patients died within 30 days of receiving anti-cancer treatment in 2019 in comparison with 7.7% in 2020. The difference in the 30-days mortality after receiving anti-cancer treatment was not statistically significant between 2019 and 2020 (p = 0.329).Conclusion: The Year 2020, the time of the COVID-19pandemic, was not associated with a significant increase in short-term mortality among patients with malignancy in Najran, Saudi Arabia. Our results generally reflect the crucial role of strict preventive national measures in saving lives and warrants further exploration.

scholarly journals Female directors in Italy: The state of art after the mandatory gender quota

2017 ◽  
Vol 14 (3) ◽  
pp. 157-169 ◽  
Author(s):  
Barbara Sveva Magnanelli ◽  
Elisa Raoli ◽  
Riccardo Tiscini
Keyword(s):  
Family Firms ◽  
The State ◽  
Board Composition ◽  
Corporate Boards ◽  
Female Directors ◽  
Before And After ◽  
The Law ◽  
The Difference ◽  
The Impact ◽  
State Of Art

The purpose of this paper is to investigate the state of art of female directors in terms of presence, role and remuneration for Italian corporate boards. The analysis wants to highlight the changes occurred after the introduction of the mandatory female quotas legislation in 2012 and to check how many firms are already complying with the law after 2 years. The picture of the state of art is drawn looking at 163 Italian listed firms for a period of 4 years, from 2011 to 2014. The analysis of the data reveals relevant differences in board composition before and after the law. A significant result concerning the presence of female directors stands in the difference between family and non-family firms: the first are those with higher number of female members in the board. Additionally, an interesting data refers to the amount of remuneration for women, which is significantly lower than the remuneration provided to male directors. Being the first work which charts the situation of board composition and board member remuneration in Italy before and after female quotas introduction, this paper wants to trace some key points for future analysis about the impact of female quotas on various firm’s aspects, such as firm performance, firm earning management and quality, governance characteristics.

scholarly journals The Impact of the Capture of Leaders of Criminal Organizations on the Labor Market: Evidence from Mexico

2021 ◽  
Author(s):  
Daniel Osuna Gómez ◽  
Keyword(s):  
Labor Market ◽  
Census Data ◽  
Negative Impact ◽  
Difference Analysis ◽  
Criminal Organizations ◽  
Before And After ◽  
Economic Census ◽  
The Difference ◽  
Integral Assessment ◽  
The Impact

This paper estimates the impact of the capture of leaders of criminal organizations on the labor market in municipalities where these organizations operated between 2004 and 2006. The difference-in-difference analysis compares different employment outcomes in cartel locations and the rest, before and after the capture of cartel leaders. The results show that captures caused a decrease in nominal wages and paid employment in cartel municipalities. Using Economic Census Data, I find that captures also caused a fall in the number of establishments and had a negative impact on other establishment outcomes. This document focuses exclusively on the impact of the capture of leaders of criminal organizations on the labor market until 2011 without studying other possible consequences, and thus does not make an integral assessment of this policy

scholarly journals Effects of Extracorporeal Membrane Oxygenation Initiation on Oxygenation and Pulmonary Opacities

2021 ◽  
Vol 7 (1) ◽  
pp. 6-13
Author(s):  
Kiran Batra ◽  
Manish Mohanka ◽  
Srinivas Bollineni ◽  
Vaidehi Kaza ◽  
Prabhakar Rajiah ◽  
...  
Keyword(s):  
Extracorporeal Membrane Oxygenation ◽  
P Value ◽  
Limited Data ◽  
Hospital Survival ◽  
Membrane Oxygenation ◽  
Pulmonary Physiology ◽  
Before And After ◽  
Laboratory Variables ◽  
The Difference ◽  
The Impact

Abstract Introduction There is limited data on the impact of extracorporeal membrane oxygenation (ECMO) on pulmonary physiology and imaging in adult patients. The current study sought to evaluate the serial changes in oxygenation and pulmonary opacities after ECMO initiation. Methods Records of patients started on veno-venous, or veno-arterial ECMO were reviewed (n=33; mean (SD): age 50(16) years; Male: Female 20:13). Clinical and laboratory variables before and after ECMO, including daily PaO2 to FiO2 ratio (PFR), were recorded. Daily chest radiographs (CXR) were prospectively appraised in a blinded fashion and scored for the extent and severity of opacities using an objective scoring system. Results ECMO was associated with impaired oxygenation as reflected by the drop in median PFR from 101 (interquartile range, IQR: 63-151) at the initiation of ECMO to a post-ECMO trough of 74 (IQR: 56-98) on post-ECMO day 5. However, the difference was not statistically significant. The appraisal of daily CXR revealed progressively worsening opacities, as reflected by a significant increase in the opacity score (Wilk’s Lambda statistic 7.59, p=0.001). During the post-ECMO period, a >10% increase in the opacity score was recorded in 93.9% of patients. There was a negative association between PFR and opacity scores, with an average one-unit decrease in the PFR corresponding to a +0.010 increase in the opacity score (95% confidence interval: 0.002 to 0.019, p-value=0.0162). The median opacity score on each day after ECMO initiation remained significantly higher than the pre-ECMO score. The most significant increase in the opacity score (9, IQR: -8 to 16) was noted on radiographs between pre-ECMO and forty-eight hours post-ECMO. The severity of deteriorating oxygenation or pulmonary opacities was not associated with hospital survival. Conclusions The use of ECMO is associated with an increase in bilateral opacities and a deterioration in oxygenation that starts early and peaks around 48 hours after ECMO initiation.

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