Examining minimal important change of the Canadian Occupational Performance Measure for subacute rehabilitation hospital inpatients

Background The Canadian Occupational Performance Measure (COPM) is an individualized patient-reported outcome designed to evaluate the self-perceptions of a patient’s occupational performance. Our study aimed to examine the minimal important change (MIC) in inpatients undergoing subacute rehabilitation. The MIC values were calculated using the three different anchor-based analyses with the transition index as an external criterion; the mean change method (MICMeanChange), the receiver operating characteristic (MICROC) analysis, and the predictive modeling method adjusted for the proportion of improved patients (MICadjust). In this study, the MICadjust value was considered as the most valid statistical method. We recruited 100 inpatients with various health conditions from subacute rehabilitation hospitals. Data were collected twice: an initial assessment and a reassessment one month later. The systematic interview format (Five Ws and How) was used for both the initial and second assessments to prevent information bias (response shift). Results Three patients who indicated deterioration on the transition index were excluded from all analyses, and 97 patients were analyzed in this study. The MICadjust values were 2.20 points (95% confidence interval 1.80–2.59) for the COPM performance score and 2.06 points (95% confidence interval 1.73–2.39) for the COPM satisfaction score. The MICMeanChange and MICROC values were considered less reasonable to interpret because the proportions of the improved patients subgroup were more than 50% (82.5%). Conclusions The MICadjust value estimates from this study can help detect whether the patients’ perceived occupational performance improved or did not change. The results support the multidisciplinary use of COPM in clinical practice and research on subacute rehabilitation inpatients.

The Effect of Oil-Water Ratio on Rheological Properties and Sag Stability of Oil-Based Drilling Fluids

Drilling fluids for oilfield use consist of complex mixtures of natural and synthetic materials. The viscous properties along with the particle size distribution of the applied weight materials are vital in controlling the stability of the microstructure and density of the drilling fluid. Typical oil-based drilling fluids made for North Sea oilfield drilling application with oil-water-ratios (OWR) of 80/20 and 60/40 are examined with respect to their density stability. The stability was analyzed both at rest and at dynamic conditions using flow and viscosity tests, oscillatory sweep tests, creep tests, and time-dependent oscillatory sweep tests using a scientific rheometer with a measuring system applying a grooved bob at atmospheric conditions. The quantities used in ranking the stability of the fluids include the yield stress, flow transition index, mechanical storage stability index, and dynamic sag index. We observed that the drilling fluid sample with OWR=60/40 showed a more stable dispersion with a stronger structure having higher yield stress and flow transition index values, while the mechanical storage stability index and dynamic sag index recorded lower values. Furthermore, the Herschel-Bulkley parameters for yield stress and consistency index increased in fluid with OWR=60/40, whereas the flow index values for both fluid samples were similar. The results of this study enable drilling fluid engineers to design realistic oil-based drilling fluids with stable microstructure to mitigate weigh material settling and sag of particles for North Sea drilling operation.

Country transition index based on hierarchical clustering to predict next COVID-19 waves

COVID-19 has widely spread around the world, impacting the health systems of several countries in addition to the collateral damage that societies will face in the next years. Although the comparison between countries is essential for controlling this disease, the main challenge is the fact of countries are not simultaneously affected by the virus. Therefore, from the COVID-19 dataset by the Johns Hopkins University Center for Systems Science and Engineering, we present a temporal analysis on the number of new cases and deaths among countries using artificial intelligence. Our approach incrementally models the cases using a hierarchical clustering that emphasizes country transitions between infection groups over time. Then, one can compare the current situation of a country against others that have already faced previous waves. By using our approach, we designed a transition index to estimate the most probable countries’ movements between infectious groups to predict next wave trends. We draw two important conclusions: (1) we show the historical infection path taken by specific countries and emphasize changing points that occur when countries move between clusters with small, medium, or large number of cases; (2) we estimate new waves for specific countries using the transition index.

Improvements and Spatial Dependencies in Energy Transition Measures

This article aims to improve one of the newest energy transition measures—the World Economic Forum WEF Energy Transition Index (ETI) and find its driving forces. This paper proposes a new approach to correct the ETI structure, i.e., sensitivity analysis, which allows assessing the accuracy of variable weights. Moreover, the novelty of the paper is the use the spatial error models to estimate determinants of the energy transition on different continents. The results show that ETI is unbalanced and includes many variables of marginal importance for the shape of the final ranking. The variables with the highest weights in ETI did not turn out to be its most important determinants, which means that they differentiate the analysed countries well; nonetheless, they do not have sufficient properties of approximating the values of the ETI components. The most important components of ETI (with the highest information load) belong to the CO2 emissions per capita, the innovative business environment, household electricity prices, or renewable capacity buildout. Moreover, we identified the clustering of both ETI and its two main pillars in Europe, which is not observed in America and Asia. The identified positive spatial effects showing that European countries need much deeper cooperation to reach a successful energy transition.

Agroecological transition in family agriculture: A case study in Primavera municipality, Brazilian Amazon

<abstract> <p>Family farmers, producing a large proportion of the food consumed by the Brazilian population, seek alternative production strategies through agroecological practices owing to financial challenges. We developed an indicator system for evaluating agroecological transition potential and analyzed farmer family profiles in a Primavera Family Farmer Cooperative. Socioeconomic and productivity data were collected through questionnaires and direct observation, and an agroecological transition index was established using factor analysis. Approximately 81% of the subsistence farmers interviewed had moderate (62%) or high potential for agroecological transition (19%), had diversified production systems, and adopted a variety of sustainable agricultural practices. However, they lived with limited infrastructure and marketed products inefficiently.</p> </abstract>

On the Stability of Oil-Based Drilling Fluid: Effect of Oil-Water Ratio

Drilling fluids are complex mixtures of natural and synthetic chemical compounds used to cool and lubricate the drill bit, clean the wellbore, carry drilled cuttings to the surface, control formation pressure, and improve the function of the drill string and tools in the hole. The two main types of drilling fluids are water-based and oil-based drilling fluids, where the oil-based also include synthetic-based drilling fluids. Many rheological properties of drilling fluids are key parameters that must be controlled during design and operations. The base fluid properties are constructed by the interaction of the emulsified water droplets in combination with organophilic clay particles. The rheological properties resulted from this combination, along with the particle size distribution of weight materials are vital in controlling the physical stability of the microstructure in the drilling fluid. A weak fluid microstructure induces settling and sagging of weight material particles. The presence of sag has relatively often been the cause for gas kicks and oil-based drilling fluids are known to be more vulnerable for sag than water-based drilling fluids. Hence, the shear-dependent viscosity and elasticity of drilling fluids are central properties for the engineers to control the stability of weight material particles in suspension. In this study, we examined the stability of typical oil-based drilling fluids made for North Sea oilfield drilling application with oil-water-ratios (OWR) of 80/20 and 60/40. The structural character of the fluid samples was analyzed both at rest and dynamic conditions via flow and viscosity curves, amplitude sweep, frequency sweep, and time-dependent oscillatory sweep tests using a rheometer with a measuring system applying a grooved bob at atmospheric conditions. A high precision density meter was used to measure the density of the drilling fluid samples before and after each test. The measurement criteria used to rank the fluids stability include the yield stress as measured from flow curves and oscillatory tests, flow transition index, mechanical storage stability index, and dynamic sag index. We observed that between the two drilling fluids, the sample with OWR = 60/40 showed a stable dispersion with stronger network structure as evidenced by higher yield stress and flow transition index values, while the mechanical storage stability index and dynamic sag index recorded lower values. The results of this study enable drilling fluid engineers to design realistic oil-based drilling fluids with stable microstructure to mitigate settling and sagging of weight material particles for North Sea drilling operation.

The Investigation on Rheology and Microstructure for Lithium Complex Grease

The rheological characteristic parameters of five lithium complex lubricating greases were determined. The comparison of rheological characteristic parameters and microstructure of the five greases was made. The results showed that the knowledge of the rheological properties of lubricating greases may contribute to reflect the change of the thickener structure. The flow transition index characterized the breaking behavior of inner structure of grease, the greater this index, the better that soap fiber structure of grease; The damping factor was shifted from a medium range towards a lower value which resulted in brittle character of sample. At a constant shear rate, the soap fiber structure of complex lithium grease is dense and uniform, apparent viscosity decline rate is small. In this sense, it is relevant to understand how the development of the soap fiber structures in the grease contributes to several functional and rheological properties of lubricating greases.