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Autism ◽  
2022 ◽  
pp. 136236132110644
Author(s):  
Sarah R Edmunds ◽  
Kyle M Frost ◽  
R Chris Sheldrick ◽  
Alice Bravo ◽  
Diondra Straiton ◽  
...  

Defining the central components of an intervention is critical for balancing fidelity with flexible implementation in both research settings and community practice. Implementation scientists distinguish an intervention’s essential components (thought to cause clinical change) and adaptable periphery (recommended, but not necessary). While implementing core components with fidelity may be essential for effectiveness, requiring fidelity to the adaptable periphery may stifle innovation critical for personalizing care and achieving successful community implementation. No systematic method exists for defining essential components a priori. We present the CORE (COmponents & Rationales for Effectiveness) Fidelity Method—a novel method for defining key components of evidence-based interventions—and apply it to a case example of reciprocal imitation teaching, a parent-implemented social communication intervention. The CORE Fidelity Method involves three steps: (1) gathering information from published and unpublished materials; (2) synthesizing information, including empirical and hypothesized causal explanations of component effectiveness; and (3) drafting a CORE model and ensuring its ongoing use in implementation efforts. Benefits of this method include: (1) ensuring alignment between intervention and fidelity materials; (2) clarifying the scope of the adaptable periphery to optimize implementation; and (3) hypothesizing—and later, empirically validating—the intervention’s active ingredients and their associated mechanisms of change. Lay abstract Interventions that support social communication include several “components,” or parts (e.g. strategies for working with children and families, targeting specific skills). Some of these components may be essential for the intervention to work, while others may be recommended or viewed as helpful but not necessary for the intervention to work. “Recommended” components are often described as “adaptable” because they can be changed to improve fit in different settings where interventions are offered or with different individuals. We need to understand which parts of an intervention are essential (and which are adaptable) when translating interventions from research to community settings, but it is challenging to do this before studying an intervention in the community. This article presents the CORE (COmponents & Rationales for Effectiveness) Fidelity Method—a new method for defining the essential components of evidence-based interventions—and applies it to a case example of Reciprocal Imitation Teaching, an intervention that parents are taught to deliver with their young children with social communication delays. The CORE Fidelity Method involves three steps: (1) gathering information from multiple sources; (2) integrating information from previous research and theory; and (3) drafting a CORE model for ongoing use. The benefits of using the CORE Fidelity Method may include: (1) improving consistency in intervention and research materials to help all providers emphasize the most important skills or strategies; (2) clarifying which parts of the intervention can be adapted; and (3) supporting future research that evaluates which intervention components work and how they work.


Author(s):  
Kevin Cleary Wanta ◽  
◽  
Ivanna Crecentia Narulita Simanungkalit ◽  
Elsha Pamida Bahri ◽  
Ratna Frida Susanti ◽  
...  

As one of the hazardous and toxic solid wastes, spent catalysts need to be treated before the waste is discharged into the environment. One of the substances that need to be removed from the spent catalysts is the heavy metal ions and/or compounds contained therein. The method that can be applied is the extraction method using an acid solvent. In this study, the extraction process was carried out on spent catalysts samples from PT. Petrokimia Gresik. The focus of the study is on nickel extraction by varying the temperature in the range of 30–85 oC. A 1 M hydrochloric acid (HCl) solution was used as a solvent while the extraction process was 120 minutes. The experimental results show that the maximum nickel recovery of 14.70% can be achieved at a temperature of 85 oC. Kinetic studies were carried out using two kinetic models. The results of both models evaluation on the research data show that the lump model gives better results than the shrinking core model. The average error percentage of the lump model is smaller than the shrinking core model. It indicates that the extraction process was controlled by the diffusion step through the ash layer in the solid and chemical reactions simultaneously.


Author(s):  
A. I. Shayakhmetov ◽  
◽  
V. L. Malyshev ◽  
E. F. Moiseeva ◽  
A. I. Ponomarev ◽  
...  

The results of experimental study of oil extraction by supercritical carbon dioxide in a low-permeability reservoir are presented. As an object of study, we selected core samples from a low-permeability oil-saturated reservoir of one of the fields in Western Siberia, which is currently being developed in the regime of depletion of reservoir energy. The contact time of supercritical carbon dioxide with composite core models in three experiments was 8, 24, and 72 hours, respectively. Based on the results of laboratory experiments, the dynamics of the penetration of carbon dioxide along the depth of the composite core model was established. The value of the oil recovery factor and it’s distribution along the length of the core model in time is given. Keywords: carbon dioxide; low-permeability reservoir; mnimum miscibility pressure; slim-tube; extraction; oil recovery.


2021 ◽  
Vol 1201 (1) ◽  
pp. 012065
Author(s):  
M G Gubaidullin ◽  
I P Belozerov

Abstract For today digital core modelling technology is demanded and developing instrument in conducting the main reservoir-capacitive properties of terrigenous rocks. This technology is becoming more widespread in connection with the development of computer and nanotechnologies. The main attempts to apply the digital core model in practice have been undertaken in the last decade, although the first examples of its use for the analysis of reservoir rocks date back to the 80s of the last century. Improvement of digital core modeling technology will allow to cope with the problem of lack or absence of core material, as well as to solve the problems of studying loose, weakly cemented and other rocks, "problematic" of conducting physical experiments. In addition, it seems relevant to create a digital core block that fits into the general digitalization platform of technologies related to reservoir-capacitive properties in the development of hydrocarbon fields. With the use of a digital core model, it also becomes possible to effectively refine and supplement the calculated parameters in laboratory core studies, reducing the likelihood of errors in the obtained results.


Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Qiji Sun ◽  
Kesen Yang ◽  
Guomin Xu ◽  
Shunde Yin ◽  
Chunsheng Wang

An artificial sandstone core model of large well group of positive rhythmic heterogeneous reservoir was designed and made for the simulation of ASP flooding experiment in the moderate heterogeneous reservoir. The well layout of one injection and one production was employed for the core model, to simulate the influence of polymer preslugs with different viscosity on ASP flooding effect. The experimental results show that the injectability of the polymer preslug and the effect of relieving the conflict of remaining oil production in each layer are related to the viscosity of the system. In the heterogeneous core model with the coefficient of variation of 0.65, under the constraint of the same amount of polymer agent, the ASP flooding effect of the 0.075 PV, 60 mPa·s polymer preslug was better than that of the 0.093 PV, 40 mPa·s and 0.064 PV, 80 mPa·s polymer preslugs. The change in the viscosity of the polymer preslug did not enable the ASP system to effectively exploit the low-permeability layer though. As the viscosity increased, the pressure difference between injection and production increased; the remaining oil could be exploited effectively at the bottom of the high-permeability layer and the medium-permeability layer as well as the injection end of the medium-permeability layer. If the viscosity is too small, the high-permeability area cannot be effectively blocked by the injected chemical agent, and if the viscosity is too large, the injected chemical agent cannot produce good elastic displacement relationship, which will lead to ineffective chemical agent flow. Therefore, the polymer preslug viscosity of the ASP flooding system should be moderate, and cores with different heterogeneity should have a reasonable viscosity matching range.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kimon Stamatelopoulos ◽  
Georgios Georgiopoulos ◽  
Kenneth F. Baker ◽  
Giusy Tiseo ◽  
Dimitrios Delialis ◽  
...  

AbstractAccurate risk stratification in COVID-19 patients consists a major clinical need to guide therapeutic strategies. We sought to evaluate the prognostic role of estimated pulse wave velocity (ePWV), a marker of arterial stiffness which reflects overall arterial integrity and aging, in risk stratification of hospitalized patients with COVID-19. This retrospective, longitudinal cohort study, analyzed a total population of 1671 subjects consisting of 737 hospitalized COVID-19 patients consecutively recruited from two tertiary centers (Newcastle cohort: n = 471 and Pisa cohort: n = 266) and a non-COVID control cohort (n = 934). Arterial stiffness was calculated using validated formulae for ePWV. ePWV progressively increased across the control group, COVID-19 survivors and deceased patients (adjusted mean increase per group 1.89 m/s, P < 0.001). Using a machine learning approach, ePWV provided incremental prognostic value and improved reclassification for mortality over the core model including age, sex and comorbidities [AUC (core model + ePWV vs. core model) = 0.864 vs. 0.755]. ePWV provided similar prognostic value when pulse pressure or hs-Troponin were added to the core model or over its components including age and mean blood pressure (p < 0.05 for all). The optimal prognostic ePWV value was 13.0 m/s. ePWV conferred additive discrimination (AUC: 0.817 versus 0.779, P < 0.001) and reclassification value (NRI = 0.381, P < 0.001) over the 4C Mortality score, a validated score for predicting mortality in COVID-19 and the Charlson comorbidity index. We suggest that calculation of ePWV, a readily applicable estimation of arterial stiffness, may serve as an additional clinical tool to refine risk stratification of hospitalized patients with COVID-19 beyond established risk factors and scores.


2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
K Stamatelopoulos ◽  
D Delialis ◽  
D Bampatsias ◽  
M E Tselegkidi ◽  
I Petropoulos ◽  
...  

Abstract Background The pattern of peripheral vascular involvement in the wild type transthyretin-related cardiac amyloidosis (ATTRwt) and its diagnostic utility in differentiating this infiltrating cardiomyopathy from light chain (AL) cardiac amyloidosis (AL-CA) and heart failure with preserved ejection fraction (HFpEF) of different origin have not been explored. Aims To characterize the pattern of peripheral vascular involvement in ATTRwt and evaluate its value in differentiating ATTRwt from AL-CA and HFpEF. Methods Newly diagnosed patients with ATTRwt (n=42) were consecutively recruited from our amyloidosis center. These patients were matched 1:1 for age and sex to patients with AL-CA (n=32) and subjects without amyloidosis (n=32) and also matched 2:1 to HFpEF patients (n=16). All subjects underwent a series of non-invasive vascular examinations for the assessment of: 1. subclinical carotid atherosclerosis with B-mode ultrasonography, 2. Arterial stiffness with measurement of carotid-femoral pulse wave velocity, 3. Reactive vasodilation with flow-mediated dilation (FMD) and 4. Aortic blood pressures and arterial wave reflections with augmentation index (AI) and return time of reflected wave (Tr). Results ATTRwt patients had lower peripheral (pBP) and aortic blood pressure (aBP) markers compared to non-AL controls (p&lt;0.05 for all). ATTRwt grouping was an independent determinant of these markers, after adjustment for cardiovascular risk factors (CVRF), including history of hypertension, hyperlipidemia and diabetes, glomerular filtration rate, body mass index and smoking status (core model). ATTRwt had lower aDBP and increased Tr compared to AL subjects. In a comparison between ATTRwt and AL patients with cardiac involvement, AI and Tr were higher and FMD lower in ATTRwt patients. ATTRwt was an independent determinant of these markers, after adjustment for the core model (p&lt;0.05 for all). Compared to HFpEF, patients with ATTRwt had lower peripheral and central BP and higher Tr (p&lt;0.05 for all). By ROC analysis, Tr provided high diagnostic value for ATTRwt vs. AL-CA (Area Under the Curve, AUC=0.809, CI: 0.65–0.96) and for ATTRwt vs combined AL-CA and HFpEF (AUC=0.880, CI: 0.79–0.97). Finally, AI was closely correlated with posterior (Spearman's Rho=−0.30) and intraventricular wall thickness (Rho=−0.329) and left ventricular global longitudinal strain (Rho=−0.4) and lower cDBP with higher Gilmore and New York Heart Association stage (p&lt;0.05). Conclusion ATTRwt patients present differential characteristics of peripheral vascular function and aortic hemodynamics as compared to AL, HFpEF and healthy controls. The clinical value of these characteristics merit further investigation since differential diagnosis among amyloidosis types is clinically challenging, while it may have prognostic implications. FUNDunding Acknowledgement Type of funding sources: None.


Metals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1560
Author(s):  
Xingqiang Xiong ◽  
Changrong Li ◽  
Zuobing Xi ◽  
Lu Chen

The aim of the experiment in this work is to modify the Al2O3 inclusions in high-carbon hard wire steel by magnesium treatment. The general evolution process of inclusions in steel is: Al2O3 → MgO·Al2O3(MA) → MgO. The unreacted core model was used to study the modification process of inclusions. The results show that the complete modification time (tf) of inclusions is significantly shortened by the increase of magnesium content in molten steel. For Al2O3 inclusions with radius of 1 μm and Mg content in the range of 0.0005–0.0055%, the modification time of Al2O3 inclusions to MA decreased from 755 s to 25 s, which was reduced by 730 s. For Al2O3 inclusions with a radius of 1.5 μm and Mg content in the range of 0.001–0.0035%, the Al2O3 inclusions were completely modified to MgO inclusions from 592 s to 55 s. The Mg content in the molten steel increased 3.4-fold, and the time for complete modification of inclusions was shortened by about 10-fold. With the increase of Al and O content in molten steel, the complete modification time increased slightly, but the change was small. At the same time, the larger the radius of the unmodified inclusion is, the longer the complete modification time is. The tf of Al2O3 inclusions with a radius of 1 μm when modified to MA is 191 s, and the tf of Al2O3 inclusions with a radius of 2 μm when modified to MA is 765 s. According to the boundary conditions and the parameters of the unreacted core model, the MgO content in inclusions with different radius is calculated. The experimental results are essentially consistent with the kinetic calculation results.


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