Operational Definition Research Articles

Renal Pelvis Urine Sampling in Patients with Obstructed, Infected Ureterolithiasis: A Retrospective Quality Improvement Initiative.

Purpose: Patients who present with urinary tract infections secondary to obstructing stones occasionally fail to improve on treatment based on midstream urine culture (MUSCx). Varying microbiomes between the bladder and the renal pelvis may account for this. In this study, we sought to investigate the utility of obtaining a renal pelvis urine culture (RPUCx) at the time of stenting to guide antibiotic treatment prior to definitive stone operation. Materials and Methods: RPUCx was obtained in 257 patients presenting with obstructive ureteral stones undergoing emergent stenting. Concordance rates of RPUCx to MUSCx and blood cultures were examined. Operative time and infectious complication rates after definitive stone management between the two groups were studied. A comparison of those who received an intraoperative RPUCx with those who did not was carried out. Results and Conclusions: RPUCx was obtained in patients undergoing emergent stenting from 2018 to -2021; 31% (52/168) of patients had pathogens in the renal pelvis that were absent in the MUSCx. RPUCx had a greater concordance rate with blood culture results compared with MUSCx (95% vs 50%). Drawing RPUCx intraoperatively did not significantly change operative time (15.9 vs 13.6 minutes, p = 0.15). Treatment tailored to RPUCx resulted in lower rates of post-stone management complications (odds ratio 0.26, 95% confidence interval = 0.08-0.83; p = 0.01). RPUCx at the time of stenting can guide treatment and decrease post-treatment complications without additional operative time, confirming utility in the treatment of patients with infection secondary to obstructing stones.

Pexidartinib and standard neoadjuvant therapy in the adaptively randomized I-SPY2 trial for early breast cancer.

We investigated the small-molecule receptor tyrosine kinase-inhibitor of colony-stimulating factor-1 receptor pexidartinib in the stage II/III breast cancer in the I-SPY2 platform trial. I-SPY2 is an adaptive platform trial that features multiple arms of experimental agents administered on a background of standard neoadjuvant therapy with paclitaxel and adriamycin/cyclophosphamide, followed by definitive surgery. The adaptive randomization engine preferentially assigns patients based upon cumulative performance of each agent in a given breast cancer subtype based on hormone receptor and HER2 receptor status. The study endpoint is pathologic complete response. A total of 9 participants were randomized to receive pexidartinib with neoadjuvant paclitaxel before enrollment was halted due to a serious adverse event of vanishing bile duct syndrome. No participants received a full course of the study drug. Although there remains interest in agents targeting CSF-1, hepatic toxicity appears to be a limiting factor for their use in early breast cancer. NCT01042379 ( www. gov/ct2/show/NCT01042379 ).

Characterization of Persister Cells Provides Insights into Mechanisms of Therapy Resistance in Neuroblastoma

Summary:The study by Grossmann and colleagues uses single-nucleus RNA sequencing in a cohort of matched high-risk neuroblastoma primary tumor samples, obtained from the same patient at diagnosis and definitive surgery, to identify persister cells that survive induction chemotherapy. These persister cells utilize mechanisms of chemoresistance that are both tumor-intrinsic and tumor-extrinsic, are highly dependent on the original genetic profile of the tumor, and represent novel, patient-specific targets to precisely inhibit chemoresistance and disease recurrence.See related article by Grossmann et.al., p. 2387

Long-term outcomes of EUS-guided gastroenterostomy: a large, single center experience

Introduction: EUS-guided gastroenterostomy (EUS-GE) is effective and safe in benign and malignant indications. However, there is a paucity of literature on the outcomes of these patients. Our study evaluates the long-term outcomes of patients who underwent EUS-GE and stent-related adverse events (AEs). Methods: This retrospective study took place at a tertiary-care institution from January 1, 2014 to December 31, 2022. Patients who underwent EUS-GE were included. Procedure details and outcomes were recorded. Patients were followed for at least 3 months after the procedure. Results: A total of 207 patients (50.3% male, mean age 62.3 years) underwent EUS-GE for malignant (N=117, 56.5%) and benign (N=90, 43.5%) indications. Overall technical success was 95.7%. Patients were followed for a mean of 406 days. Stents were removed in 25.6% of patients; common reasons include completed access for endoscopic retrograde cholangiopancreatography (ERCP) (N=13, 25%), resection/resolution of gastric outlet obstruction (GOO) (N=28, 53.8%), and surgical resection of malignant GOO (N=8, 15.4%). EUS-GE stents remained in place in 63.6% of patients for ≥3 months and in 21% of patients for ≥1 years. Late AEs occurred in 3.4%. Among patients who were stent-dependent (N=24, 11.6%) and underwent annual stent exchanges, no late AEs occurred. Discussion: Long-term outcomes of EUS-GE are promising with few adverse events, particularly with preemptive annual exchanges of stents to prevent stent delamination and occlusion among patients who require long-term indwelling stents. EUS-GE has an increasing role in access for ERCP in altered anatomy, acute or chronic management of benign GOO, or bridge to definitive surgery for GOO.

Policy Proposals for Mitigating Intensive Care Unit Strain: Insights from the COVID-19 Pandemic.

Intensive care unit (ICU) strain, characterized by a discrepancy between perceived or actual intensive care resources and demand, significantly impacts patient outcomes and healthcare worker well-being. The coronavirus disease (COVID-19) pandemic exacerbated ICU strain, leading to increased mortality and extended hospital stays, affecting both critically ill patients with and without COVID-19. A systematic review identified 16 leading and lagging indicators of ICU capacity strain, including queuing, premature and after-hours ICU discharge, use of temporary space, length of stay, burnout, staffing and nurse-to-patient ratio, ICU census, acuity and turnover, standardized mortality ratio, readmissions, availability of critical supplies, ventilator use, and surgery cancellation. However, variability in operational definitions and limited evidence regarding the reliability, validity, usability, and feasibility limit the value of single indicators for informed strategic planning and policy guidance. Regional and national policies and programs are essential to enhance real-time monitoring for effective management of critical care resources, and they mitigate the impact of ICU strain, facilitating complex interhospital transfers to reduce strain and ensuring comprehensive strategies for enhancing ICU resilience. Proactive regional cooperation is advocated for policy formulation, knowledge exchange, and resource allocation to anticipate and mitigate ICU strain, ensuring equitable healthcare access during global health crises. The policy implications for future preparedness emphasize the importance of evidence-based triage and adaptable patient management strategies alongside ethical considerations in resource allocation and the role of behavioral economic insights in optimizing resource utilization and collaborative healthcare practices. This multifaceted approach for addressing ICU strain comprehensively and effectively during a pandemic would promote health equity and enhance healthcare system resilience under both routine operations and crisis conditions.

Efficacy of Vitamin E Versus Pioglitazone in Treating Non-Alcoholic Fatty Liver Disease (NAFLD) without Diabetes “Decoding the Exodus of Liver Health”.

Objective: To compare the effectiveness of vitamin E in comparison with Pioglitazone in the management of NAFLD without Diabetes. Study Design: Randomized Control Trial. Setting: Outpatient Department of Allied Hospital, Faisalabad. Period: Dec 2023 to May 2024. Methods: The Ethics Review Committee of Faisalabad Medical University was taken on board and patients having the characteristics of the set Inclusion Criteria were enrolled as allowed. Selected individuals were counseled regarding the study and their consent was sought. Using a computer-generated random number table, two main groups were formed out of the participants, Group A and Group B. Group A was given 800IU of Vitamin E daily. Group B received Pioglitazone 30mg daily. Patients were monitored for efficacy over three months by tracking ALT levels as specified in the operational definition. Follow-up was ensured through contact numbers. Results: In our study of 722 cases (361 in each group), the mean age was 41.25±6.41 years in Group A and 41.23±6.56 years in Group B. Males comprised 60.11% (n=217) of Group A and 59.56% (n=215) of the Group B, while females accounted for 39.89% (n=144) out of Group A and 40.44% (n=146) of the Group B. Efficacy comparison showed that 49.72% (n=147) in Group A and 31.30% (n=113) in Group B achieved efficacy, with a p-value of 0.008, pointing out a considerable difference. Conclusion: Our study succeeded in establishing the better efficacy of Vitamin E in treating NAFLD compared to Pioglitazone.

All In: Understanding and Motivating Stakeholders to Create an Equitable Culture of Student Success.

Discourse around Science, Technology, Engineering, and Mathematics (STEM) education in the United States has long focused on improving the persistence and academic achievement of students. On the surface, such goals are reasonable and well-intentioned. However, the near-exclusive focus on those two outcomes as shorthand for "success" serves hegemonic norms which preclude the equitable success of all students. Although STEM education research has begun to address the inequitable systems within which students and faculty operate, the language of success has largely not changed. While previous work has aimed to recognize and characterize how normative definitions of success harm students and faculty, they fall short of providing readers with strategies for how to sustainably change these systems of injustice. Utilizing the four frames model for systemic change, this Essay 1) deconstructs the operational definitions of student success among key stakeholders involved in STEM higher education: students, faculty, departments, and institutions; 2) determines how extant policies and practices drive misalignments among these definitions and thwart equity; and 3) highlights three key opportunities for change agents to transform how success is measured and defined within STEM higher education.

On soil districts

In 2023, the European Commission released a legislative proposal for a Directive on Soil Monitoring and Resilience which aims to define a legal framework to achieve healthy soils across the European Union (EU) by 2050. A key component of the initial Directive is the mandate for Member States to establish basic geographic soil governance units, referred to as soil districts, and appoint a district-specific authority to oversee the implementation of soil health assessments. This paper proposes an operational definition of the districts following the conditions outlined in the proposal for the Directive and discusses various attention points for their implementation. Tentative districts were developed for seven EU countries, considering soil type, climate, topography, and land cover factors, starting from the smallest existing administrative unit (i.e. municipalities). Experts were asked to report on the applicability of the proposed districts within well-known pedo-ecological regions and discuss the relevance of the districts for establishing an EU-wide monitoring network and reporting on soil health and degradation. The outcomes highlight the need for detailed soil maps to account for specific soil types when stratifying countries into soil districts. The soilscape approach allows for a consistent method to defining soil districts across Member States. This enables contrasting soils within a district to be managed in a similar manner, with soil degradation/health thresholds applied to each district based on land cover. However, it is unclear whether soil districts as currently formulated in the Directive are in fact the right tool to support local soil management and monitoring of soil health. Districts can help ensure that all soil conditions are covered in a monitoring system, but they may not provide support for soil management or monitoring at a local scale due to short-scale soil variability and threats affecting soil management within the same soilscape. Beyond the use of districts for designing a European/national scale monitoring system, the districts can help create animations and other educational tools to promote soil literacy and connectivity of users to soils locally.

Benzodiazepine rescue medication administration for seizure clusters: Real-world retrospective outcomes.

Benzodiazepine rescue medications are established as therapy for acute termination of seizure clusters. A post-hoc analysis of a clinical trial of seizure cluster treatment with diazepam nasal spray found a potential longer-term impact over a year of treatment. In this retrospective analysis, we tested the hypothesis that benzodiazepine-treated seizure clusters are associated with prolonged time to the next seizure cluster compared with untreated seizure clusters in a patient-reported real-world database. We analyzed data on self-reported seizures and benzodiazepine rescue medication administration in the Seizure Tracker™ database between 2007 and 2022. Kaplan-Meier analysis was used to compare treated vs untreated seizure clusters with respect to time to start of the next seizure cluster or immediate-use medication administration. Mixed-effects analysis was used to compare the number of seizures per cluster for treated and untreated seizure clusters. Robustness of findings was evaluated across three operational seizure-cluster definitions: ≥2 seizures in 4 hours as primary analysis and in 6 and 24 hours as sensitivity analyses. A total of 10 889 benzodiazepine immediate-use medication administrations (n = 220 patients) met inclusion criteria. Benzodiazepine rescue administrations were followed by longer time to the next seizure cluster or rescue administration, compared with untreated seizure clusters, corresponding to a median of 4.9 days following treated seizure clusters and a median of 0.8 days following untreated seizure clusters. This prolongation was driven by a minority of patients (accounting for 45.9% of seizure clusters in the sample) and patients were more likely to be women. The number of seizures per cluster was lower when treatment was administered earlier in the seizure cluster. These retrospective real-world data suggest that the effect of benzodiazepines on termination of seizure clusters may be more pronounced when administration occurs earlier after onset, and support a hypothesis of a possible longer-term effect of benzodiazepines beyond immediate-use acute seizure termination.

Screening for frequent hospitalization risk among community-dwelling older adult between 2016 and 2023: machine learning-driven item selection, scoring system development, and prospective validation

BackgroundScreening for frequent hospitalizations in the community can help prevent super-utilizers from growing in the inpatient population. However, the determinants of frequent hospitalizations have not been systematically examined, their operational definitions have been inconsistent, and screening among community members lacks tools. Nor do we know if what determined frequent hospitalizations before COVID-19 continued to be the determinant of frequent hospitalizations at the height of the pandemic. Hence, the current study aims to identify determinants of frequent hospitalization and their screening items developed from the Comprehensive Geriatric Assessment (CGA), as our 273-item CGA is too lengthy to administer in full in community or primary care settings. The stability of the identified determinants will be examined in terms of the prospective validity of pre-COVID-selected items administered at the height of the pandemic.MethodsComprehensive Geriatric Assessments (CGAs) were administered between 2016 and 2018 in the homes of 1,611 older adults aged 65+ years. Learning models were deployed to select CGA items to maximize the classification of different operational definitions of frequent hospitalizations, ranging from the most inclusive definition, wherein two or more hospitalizations over 2 years, to the most exclusive, wherein two or more hospitalizations must appear during year two, reflecting different care needs. In addition, the CGA items selected by the best-performing learning model were then developed into a random-forest-based scoring system for assessing frequent hospitalization risk, the validity of which was tested during 2018 and again prospectively between 2022 and 2023 in a sample of 329 older adults recruited from a district adjacent to where the CGAs were initially performed.ResultsSeventeen items were selected from the CGA by our best-performing algorithm (DeepBoost), achieving 0.90 AUC in classifying operational definitions of frequent hospitalizations differing in temporal distributions and care needs. The number of medications prescribed and the need for assistance with emptying the bowel, housekeeping, transportation, and laundry were selected using the DeepBoost algorithm under the supervision of all operational definitions of frequent hospitalizations. On the other hand, reliance on walking aids, ability to balance on one’s own, history of chronic obstructive pulmonary disease (COPD), and usage of social services were selected in the top 10 by all but the operational definitions that reflect the greatest care needs. The prospective validation of the original risk-scoring system using a sample recruited from a different district during the COVID-19 pandemic achieved an AUC of 0.82 in differentiating those rehospitalized twice or more over 2 years from those who were not.ConclusionA small subset of CGA items representing one’s independence in aspects of (instrumental) activities of daily living, mobility, history of COPD, and social service utilization are sufficient for community members at risk of frequent hospitalization. The determinants of frequent hospitalization represented by the subset of CGA items remain relevant over the course of COVID-19 pandemic and across sociogeography.

Multidisciplinary Approach of a Male Case of Imported Malaria, HIV Chronic Infection, and Latent Syphilis

Background: The current economic and social crisis in Latin America has caused migration to the USA, bringing with it Public Health challenges due to the importation of various infectious diseases. Migrants, particularly those with chronic conditions, such as HIV infection and other sexually transmitted infections (STI), are at greater risk due to pharmacological interruption and access to medical care, so the timely detection of diseases acquired during their migration, such as malaria, is crucial to avoid health complications. Objective: To outline by a multidisciplinary approach (Infectology, Parasitology, Epidemiology, molecular Biology, Venereology, and Public Health) the diagnosis and management of a male case with malaria imported to Mexican territory, HIV chronic infection, and latent syphilis. Methods: A male migrant of Venezuelan nationality attended the Clínica Especializada Condesa Iztapalapa in Mexico City for health complications. A comprehensive analysis of laboratory and molecular tests was performed to confirm HIV infection. During the STI diagnostic algorithm, latent syphilis was detected and microscopic observation of blood smears revealed parasitic forms compatible with malaria. Standard and molecular tests were applied under the operational definition for malaria cases for identification, diagnosis, and treatment. Finally, study of clinical history and migration route by questioning for the investigation of the imported case was performed. Results: The immigrant was diagnosed with HIV chronic-stage infection with interrupted antiretroviral therapy (ART), latent syphilis, and malaria by Plasmodium vivax. The ART administered was chosen based on the possible drug interaction with antimalarials and genetic barrier to the HLA-B* allele. Finally, antimicrobial therapy against syphilis was penicillin. From the analysis of the migratory route, incubation time of imported malaria, and questioning, we speculated that the migrant acquired the P. vivax infection in Panama. Conclusions: This case highlights the complex health problems faced by migrants with HIV infection, particularly when they contract additional infections such as malaria during migration and highlights the need for comprehensive access to healthcare and ART, antimalarial and antimicrobial treatments to mitigate the health risks of this vulnerable population.

The development of an “Engagement in Physical Education” scale

PurposeThe purpose of this paper is to present a scale that assesses students' perceptions of their engagement in physical education. The scale assesses all four dimensions of engagement (agentic, cognitive, behavioral, and emotional) in order to be consistent with the contemporary notion of engagement used in current educational research.MethodA total of 231 eighth and ninth-grade students (108 boys, Mage = 14.55) completed a 21-item scale, with items taken from previously validated scales, but with an added string relating to physical education lessons. Following model respecification by the examination of standardized residual covariances to remove items, the factor loading for each of the items on the scale was examined.ResultsThe results from a confirmatory factor analysis showed that there was psychometric support for an 18-item survey in which each of the four a priori latent variables was kept in the validation of the four-factor hypothesized model. [χ2 = 226.01, df = 125, χ2/df = 1.808, GFI = .903, RMSEA (90% CI) = .061 (.048–.073)].ConclusionGiven the research on engagement within physical education has been beleaguered by the lack of a robust operational definition, this scale allows for the comprehensive measurement of the different components of engagement.

The relationships between balanced-bilingual proficiency, executive function, and rational thinking: a dissociative finding

ABSTRACT The cognitive advantages of bilingualism have accumulated significant support in various domains, and executive function is suggested to be one of their operative mechanisms. However, empirical evidence of the relationships among bilingualism, executive function, and rational thinking is still lacking. The present study extends this understanding. With a refined operational definition of bilingualism and by controlling for possible confounding variables, we recruited 114 university participants to perform a balanced bilingual proficiency task; a modified Simon executive function (EF) task (to assess inhibition and updating components of EFs); a syllogism task; a critical thinking test; and measures of intelligence, socioeconomic status (SES), and the openness-to-experience personality trait. The results showed that balanced bilingual proficiency positively and robustly predicted participants’ performance in syllogism and critical thinking tasks after we controlled for other variables. The relationships between EF components and rational thinking showed a dissociative result: Inhibition and updating ability contributed to syllogistic and critical thinking differently. These results shed further light on the educational application needs of bilingual learning and concluded in a discussion of future investigations of the theoretical accounts and mechanisms of bilingual advantages.

About Whom Are We Talking When We Use Intellectual and Developmental Disabilities?

Communicating clearly about who is included in a population group is a critical element to effective dissemination and knowledge transfer. This narrative review highlights the inconsistency as it relates to communicating about individuals with intellectual disability (ID) and developmental disability (DD). There is enormous variability in the use of definitions and abbreviations in the field of intellectual disability and developmental disabilities. The lack of consistency has resulted in widely varying reported rates of prevalence and has contributed to confusion around the interpretation of research and clinical findings, population statistics, and policy decisions. The reported rates of prevalence for developmental disabilities published by different US federal agencies have ranged widely from 3% to 17%. This represents a 5-fold difference. Equally confusing is the inconsistent and ambiguous adoption of initialisms. These initialisms include ID/DD, IDD, and I/DD for which it is not always clear if these initialisms reference separate and independent populations (eg, ID or DD) or populations with co-occurring conditions (eg, persons with ID and DD). This Narrative Review discusses these issues and proposed a number of recommendations that would contribute to enhanced consistency and clarity of understanding for stakeholders, administrators, practitioners, researchers, and policy makers. Authors of scholarly works, clinical publications, policies, and position papers are encouraged to provide a clear operational definition as well as the choice of initialisms used (eg, ID/DD, IDD, I/DD, etc) when it is first used.

Barriers and facilitators to point-of-care ultrasound use in an academic emergency department by perceived usability

BackgroundWhile use of point-of-care ultrasound (POCUS) has become widespread in emergency medicine, its adoption and usage among emergency clinicians is variable. In this study, we explored the barriers and facilitators to POCUS use among emergency medicine clinicians in a tertiary care emergency department in the United States by clinical role and perceived usability of POCUS. MethodsWe initially administered a quantitative survey via REDCap and used a validated technology usability scale to categorize clinicians into tertiles of low, moderate, and high, based on perceived utility of POCUS. Subsequently, a purposeful sample in each category participated in semi-structured interviews until thematic saturation was reached (9–10 per category, 29 total). The qualitative interviews were analyzed using Braun and Clark's content analysis approach. A coding scheme was developed through initial review of 20 % of the transcripts, followed by operational definitions of codes, concept and category development, and selection of representative quotes. Analysis was supported by Dedoose software. ResultsWe identified 41 % (12/29) as high POCUS users, 31 % (9/29) as moderate, and 28 % (8/29) as low, based on perceived usability. Interviewees consisted of 24 % (7/29) attendings, 28 % (8/29) residents and 48 % (14/29) advanced practice providers (APPs). Attendings made up 50 % in the high POCUS group and 75 % of the low POCUS group were APPs. In the low group, the lack of prior and present POCUS training was a major barrier to POCUS use. The lack of time during clinical shifts was a major barrier to POCUS utility in the high and low groups. Availability of POCUS machines in clinical spaces was identified as a facilitator to POCUS use in the medium group. ConclusionsParticipants reported that POCUS facilitates patient disposition and clinical supervision enhances its use. Early POCUS education in professional school and continued POCUS training in clinical practice could facilitate POCUS use clinically. Structured POCUS courses and continued medical education programs may provide protected time to learn and practice POCUS. Moreover, accessible and standardized machines in the clinical environment could improve POCUS usage.

Total colonic aganglionosis: management and long-term outcomes at a referral centre.

The management of total colonic aganglionosis (TCA) in low-middle income countries (LMIC) is challenging. We aimed to analyze the profile, management, and outcome of patients with TCA at an Indian referral centre. A retrospective review of demography, presentation, investigations, and treatment of patients with TCA at a single centre over 22 years with a standardized protocol is detailed. Long-term outcome was assessed with qualitative evaluation and bowel function score. Twenty-two patients were reviewed. Although neonatal intestinal obstruction was common, 36% had chronic constipation. Delayed meconium history was evident in 54% and a classical microcolon in 28%. 71% of contrast enemas were incongruent with the final histological diagnosis. The median time on a levelled stoma was 13months. 45.5% had 15 interim surgical interventions, including 8 relevelling (36%) before the definitive surgery at a median age of 19.5 months. At a mean follow-up age of 10.3years, eleven had a bowel function score of ≥ 17 and five others had a favorable qualitative outcome. The diagnosis, histological levelling and management of TCA continues to be challenging in LMIC. The morbidity and long-term outcomes with the described protocol were comparable to studies from developed nations.

Once is enough! An analogue study on repeated validity assessment in adults with ADHD

Performance validity tests (PVTs) can be seen as gatekeepers for valid neuropsychological assessment, by marking cognitive test scores that may not reflect true ability levels. The present study explored the significance of repeated validity testing of adults with attention-deficit/hyperactivity disorder (ADHD), by exploring the potential value of performance consistency across assessments. The operational definition of performance consistency was determined by calculating the mean variation in a participant’s PVT scores across three separate assessments. Neuropsychological test data of 24 individuals diagnosed with ADHD were complemented by an analogue study involving 69 typically developing individuals who were allocated to either a control group or a simulation group instructed to feign ADHD. All individuals were assessed with embedded and stand-alone PVTs three times with one-month intervals between each assessment. The rate of failed validity testing remained rather stable across assessments. Significant differences in neuropsychological performance scores occurred between individuals with ADHD and experimental simulators, however, mostly nonsignificant effects of small size emerged when considering performance consistency. Our data demonstrate that the consistency of cognitive performance over repeated assessments may be no effective approach to complement validity assessment. Replication is needed in independent research on larger samples.

The Concept of Weight as Reflecting the Epistemological Changes in Physics

AbstractThe goal of this study was to elicit and juxtapose the account of the concept of weight in history vis a vis physics education. The results reveal the problem of consistency in the currently employed teaching materials. The weight concept is very old and remains ubiquitous in science. Its history reflects the maturation of scientific methodology. The latter implied three periods of its development: old, classical, and modern. The “old” weight designated heaviness, or gravity, of bodies and the quantity of matter, both measured through weighing by balance. The “old” weight served as the basis for trade and technology. “Old” weight split in the scientific revolution of the seventeenth century into mass and gravitational force that explained the weight of massive objects—weight was identified with gravitational force. The third period followed the scientific revolution of the twentieth century. Classical Mechanics adopted the equivalence principle and included the accelerated observers. This implied redefinition of weight by the operational definition as the result of weighing. Thus, weight was distinguished from the gravitational force. All three periods reflect the change of physics methodology. In education, physics textbooks are currently divided between the contradictory accounts of the second and third periods of weight history. The weight concept is often confused by students who show numerous related misconceptions. Facing this complexity, we argue for using weight teaching as a tool for promoting the modern perspective of knowledge construction in physics, its epistemology, that is, revealing the nature of science, the need for a reliable operational definition alongside a theoretical one, to the students. The teaching in accordance with the discipline-culture paradigm emphasizes the discursive nature of science, reveals the conceptual dialogue, and suggests its presentation in science/physics classes.

Mismatch Vs No Mismatch in Large Core-AMatter of Definition.

Endovascular thrombectomy (EVT) has shown promise in randomized controlled trials (RCTs) for large ischemic core stroke patients, yet variability in core definition and onset-to-imaging time creates heterogeneity in outcomes. This study aims to clarify the prevalence and implications of core-perfusion mismatch (MM) versus no mismatch (No MM) in such patients, utilizing established imaging criteria. Aretrospective cohort study was conducted including patients from 7/29/2019 to 1/29/2023, with data extracted from acontinuously maintained database. Patients were eligible if they met criteria including multimodal CT imaging performed within 24 h from last known well (LKW), AIS-LVO diagnosis, and ischemic core size defined by specific rCBF thresholds. Mismatch was assessed based on different operational definitions from the EXTEND and DEFUSE 3trials. Fifty-two patients were included, with various time windows from LKW. Using EXTEND criteria, asignificant portion of early window patients exhibited MM; however, fewer patients met MM criteria in the late window. Defining MM using DEFUSE 3criteria yielded similar patterns, but with overall lower MM prevalence in the late window. When employing rCBF <38% as asurrogate for ischemic core, ahigher percentage of patients were classified as MM across both time windows compared to rCBF <30%. The prevalence of MM in large ischemic core patients varies significantly depending on the imaging criteria and time from LKW. Notably, MM was more prevalent in the early time window across all criteria used. Additional RCTs are needed to determine if this definition of MM identifies patients who will benefit most from EVT.

Visual Modeling Languages in Patient Pathways: Scoping Review.

Patient pathways (PPs) are presented as a panacea solution to enhance health system functions. It is a complex concept that needs to be described and communicated well. Modeling plays a crucial role in promoting communication, fostering a shared understanding, and streamlining processes. Only a few existing systematic reviews have focused on modeling methods and standardized modeling languages. There remains a gap in consolidated knowledge regarding the use of diverse visual modeling languages. This scoping review aimed to compile visual modeling languages used to represent PPs, including the justifications and the context in which a modeling language was adopted, adapted, combined, or developed. After initial experimentation with the keywords used to describe the concepts of PPs and visual modeling languages, we developed a search strategy that was further refined and customized to the major databases identified as topically relevant. In addition, we consulted gray literature and conducted hand searches of the referenced articles. Two reviewers independently screened the articles in 2 stages using preset inclusion criteria, and a third reviewer voted on the discordance. Data charting was done using an iteratively developed form in the Covidence software. Descriptive and thematic summaries were presented following rounds of discussion to produce the final report. Of 1838 articles retrieved after deduplication, 22 satisfied our inclusion criteria. Clinical pathway is the most used phrase to represent the PP concept, and most papers discussed the concept without providing their operational definition. We categorized the visual modeling languages into five categories: (1) general purpose-modeling language (GPML) adopted without major extension or modification, (2) GPML used with formal extension recommendations, (3) combination of 2 or more modeling languages, (4) a developed domain-specific modeling language (DSML), and (5) ontological modeling languages. The justifications for adopting, adapting, combining, and developing visual modeling languages varied accordingly and ranged from versatility, expressiveness, tool support, and extensibility of a language to domain needs, integration, and simplification. Various visual modeling languages were used in PP modeling, each with varying levels of abstraction and granularity. The categorization we made could aid in a better understanding of the complex combination of PP and modeling languages. Standardized GPMLs were used with or without any modifications. The rationale to propose any modification to GPMLs evolved as more evidence was presented following requirement analyses to support domain constructs. DSMLs are infrequently used due to their resource-intensive development, often initiated at a project level. The justifications provided and the context where DSMLs were created are paramount. Future studies should assess the merits and demerits of using a visual modeling language to facilitate PP communications among stakeholders and use evaluation frameworks to identify, modify, or develop them, depending on the scope and goal of the modeling need.