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* Context.-Machine learning applications in the pathology clinical domain are emerging rapidly. As decision support systems continue to mature, laboratories will increasingly need guidance to evaluate their performance in clinical practice. Currently there are no formal guidelines to assist pathology laboratories in verification and/or validation of such systems. These recommendations are being proposed for the evaluation of machine learning systems in the clinical practice of pathology. Objective.-To propose recommendations for performance evaluation of in vitro diagnostic tests on patient samples that incorporate machine learning as part of the pre-analytical, analytical, or post-analytical phases of the laboratory workflow. Topics described include considerations for machine learning model evaluation including risk assessment, predeployment requirements, data sourcing and curation, verification and validation, change control management, human-computer interaction, practitioner training, and competency evaluation. Data Sources.-An expert panel performed a review of the literature, Clinical and Laboratory Standards Institute guidance, and laboratory and government regulatory frameworks. Conclusions.-Review of the literature and existing documents enabled the development of proposed recommendations. This white paper pertains to performance evaluation of machine learning systems intended to be implemented for clinical patient testing. Further studies with real-world clinical data are encouraged to support these proposed recommendations. Performance evaluation of machine learning models is critical to verification and/or validation of in vitro diagnostic tests using machine learning intended for clinical practice. (Arch Pathol Lab Med. 2024;148:e335-e361; doi: 10.5858/arpa.2023-0042-CP), Institution of machine learning (ML) in the pathology clinical domain has gained momentum and is rapidly advancing. As ML-based clinical decision support (CDS) systems continue to mature, laboratories will increasingly [...]

Abstract Background Despite the pressing need for the creation of applications that facilitate the aggregation of clinical and molecular data, most current applications are proprietary and lack the necessary compliance with standards that would allow for cross-institutional data exchange. In line with its mission of accelerating research discoveries and improving patient outcomes by linking networks of researchers, physicians, and patients focused on cancer research, caBIG (cancer Biomedical Informatics Grid™) has sponsored the creation of the caTRIP (Cancer Translational Research Informatics Platform) tool, with the purpose of aggregating clinical and molecular data in a repository that is user-friendly, easily accessible, as well as compliant with regulatory requirements of privacy and security. Results caTRIP has been developed as an N-tier architecture, with three primary tiers: domain services, the distributed query engine, and the graphical user interface, primarily making use of the caGrid infrastructure to ensure compatibility with other tools currently developed by caBIG. The application interface was designed so that users can construct queries using either the Simple Interface via drop-down menus or the Advanced Interface for more sophisticated searching strategies to using drag-and-drop. Furthermore, the application addresses the security concerns of authentication, authorization, and delegation, as well as an automated honest broker service for deidentifying data. Conclusion Currently being deployed at Duke University and a few other centers, we expect that caTRIP will make a significant contribution to further the development of translational research through the facilitation of its data exchange and storage processes.

The rapid melting of glaciers and thawing of permafrost in mountainous regions have heightened the danger of rock‐ice avalanches. These avalanches pose a severe threat due to their potential to transform into water‐saturated debris flows. The catastrophic event in Chamoli, India, on 7 February 2021, illustrates the devastating consequences of such processes. Developing a model capable of predicting the dynamics and extent of these events is imperative for natural hazard science and disaster mitigation. In response, we propose a depth‐averaged rock‐ice avalanche model encompassing four distinct materials: rock, ice, snow, and water. The model integrates crucial physical processes, including frictional heating, phase changes, ground material entrainment, and air‐blast hazards. Through a system of mass and momentum balance equations extended with grain flow and internal energy equations, the model captures heat exchanges and resulting phase changes as the fragmented material flows. Focusing on identifying the primary water source in the flow and testing the model on the 2021 Chamoli event, we quantify water's influence on flow dynamics and regime transitions. However, uncertainties persist in heat transfer physics and quantifying the hydro‐meteorological state of the flow path. Our thermo‐mechanical model enables the simulation of complex avalanches and identifies key flow transitions: powder cloud formation and potential debris flow transformation. The study underscores the pivotal role of water in avalanche dynamics and the challenge of accurately quantifying water content within the flow, necessitating comprehensive ground assessments for effective disaster management. Plain Language Summary: In the context of global climate warming, the rapid melting of glaciers and thawing of permafrost lead to rock and ice mass collapses, forming rock‐ice avalanches. These can evolve into water‐saturated debris flows, increasingly endangering societies and infrastructures in hazard‐prone regions. The 2021 Chamoli rock‐ice avalanche, which transformed into a debris flow causing over 200 fatalities, exemplifies the severe consequences of such natural disasters. To address this issue, we developed a depth‐averaged model to predict the complex dynamics characteristics of rock‐ice events. The model considers various components like rock, ice, snow, and water, along with crucial processes such as frictional heating, phase changes, material entrainment, and air‐blast hazards; and captures heat changes between phases and resultant phase transitions. Using this model, we investigated the primary water source within avalanche flows and its effects on dynamics, focusing on the 2021 Chamoli avalanche. Our findings highlight the pivotal role of water in shaping the behavior of these rock‐ice events and flow transitions. Despite significant progress, challenges remain in refining our understanding of heat transfer physics and quantifying hydro‐meteorological conditions within the flow. Nevertheless, our thermo‐mechanical model represents a significant advancement in simulating and comprehensively analyzing the dynamics of rock‐ice avalanches. Key Points: New depth‐averaged model for rock‐ice avalanches, including rock, ice, snow, and water, phases changes, ground entrainment and air blastOur model identifies three key flow transitions: powder cloud formation, debris flow transformation, and hyperconcentrated flood occurrenceModel testing shows water's impact on flow transitions. Uncertainties remain in heat transfer and entrainment calling for more validation [ABSTRACT FROM AUTHOR]

Background: Molecular testing of thyroid nodules is an essential tool to help risk stratify nodules with indeterminate cytology. Although ThyroSeq testing has been around for over a decade, there is a paucity of long‐term follow‐up data on cytologically indeterminate nodules that are determined to be molecularly negative or low‐risk. The objective of this study is to assess the outcomes of nodules with indeterminate cytology (Bethesda III or IV) and negative or low‐risk ThyroSeq results. Methods: This is a single academic institution retrospective cohort study. Patients with at least one thyroid nodule sampled with fine‐needle aspiration who underwent ThyroSeq testing from 2012 to 2018 and had negative or low‐risk ThyroSeq results on a cytologically indeterminate sample (n = 159 patients, 167 nodules) were included in the study. Outcomes include the false‐negative rate and negative predictive value of each test version, as well as follow‐up length for each nodule. Results: There were 159 patients with a mean age of 58 years (7–84 years) included in this study; the majority were female (81.8%). The mean follow‐up was 4.0 years. Of 167 nodules, three were found to be malignant on resection (1.8%). The negative predictive value for the entire cohort was 98.2% and it was 89.3% for the surgical series. Conclusion: ThyroSeq testing has good negative predictive value and can help risk stratify cytologically indeterminate nodules. Routine follow‐up allows for safe monitoring of nodules for features suggestive of malignancy. ThyroSeq testing can be used to risk stratify cytologically indeterminate nodules and decrease the number of unnecessary surgeries due to its low rates of false negatives and a high negative predictive value. [ABSTRACT FROM AUTHOR]

Background: COVID-19 spurred rapid adoption and expansion of telemedicine. We investigated the factors driving visit modality (telemedicine vs. in-person) for outpatient visits at a large cardiovascular center. Methods: We used electronic health record data from March 2020 to February 2021 from four cardiology subspecialties (general cardiology, electrophysiology, heart failure, and interventional cardiology) at a large academic health system in Northern California. There were 21,912 new and return visits with 69% delivered by telemedicine. We used hierarchical logistic regression and cross-validation methods to estimate the variation in visit modality explained by patient, clinician, and visit factors as measured by the mean area under the curve. Results: Across all subspecialties, the clinician seen was the strongest predictor of telemedicine usage, while primary visit diagnosis was the next most predictive. In general cardiology, the model based on clinician seen had a mean area under the curve of 0.83, the model based on the primary diagnosis had a mean area under the curve of 0.69, and the model based on all patient characteristics combined had a mean area under the curve of 0.56. There was significant variation in telemedicine use across clinicians within each subspecialty, even for visits with the same primary visit diagnosis. Conclusion: Individual clinician practice patterns had the largest influence on visit modality across subspecialties in a large cardiovascular medicine practice, while primary diagnosis was less predictive, and patient characteristics even less so. Cardiovascular clinics should reduce variability in visit modality selection through standardized processes that integrate clinical factors and patient preference. [ABSTRACT FROM AUTHOR]

BackgroundA novel MRI technique, employing dual contrast manganese-enhanced MRI (MEMRI) and delayed enhancement MRI (DEMRI), can evaluate the physiologically unstable peri-infarct region. Dual contrast MEMRI-DEMRI enables comprehensive evaluation of telmisartan to salvage the peri-infarct injury to elucidate the underlying mechanism of restoring the ischemic cardiomyopathy in the diabetic mouse model.Methods and resultsDual contrast MEMRI-DEMRI was performed on weeks 1, 2, and 4 following initiation of telmisartan treatment in 24 left anterior descendent artery ligated diabetic mice. The MRI images were analyzed for core infarct, peri-infarct, left ventricular end-diastolic, end-systolic volumes, and the left ventricular ejection fraction (LVEF). Transmission electron microscopy (TEM) and real-time PCR were used for ex vivo analysis of the myocardium. Telmisartan vs. control groups demonstrated significantly improved LVEF at weeks 1, 2, and 4, respectively (33 ± 7 %*** vs. 19 ± 5 %, 29 ± 3 %*** vs. 22 ± 4 %, and 31 ± 2 %*** vs 18 ± 6 %, ***p < 0.001). The control group demonstrated significant differences in the scar volume measured by MEMRI and DEMRI, demonstrating peri-infarct injury. Telmisartan group significantly salvaged the peri-infarct injury. The myocardial effects were validated by TEM, which confirmed the presence of the injured but viable cardiomyocyte morphology in the peri-infarct region and by flow cytometry of venous blood, which demonstrated significantly increased circulating endothelial progenitor cells (EPCs).ConclusionThe improved cardiac function in ischemic cardiomyopathy of diabetic mice by telmisartan is attributed to the attenuation of the peri-infarct injury by the angiogenic effects of EPCs to salvage the injured cardiomyocytes. Dual-contrast MEMRI-DEMRI technique tracked the therapeutic effects of telmisartan on the injured myocardium longitudinally.

Early in the COVID-19 pandemic, cardiology clinics rapidly implemented telemedicine to maintain access to care. Little is known about subsequent trends in telemedicine use and visit volumes across cardiology subspecialties. We conducted a retrospective cohort study including all patients with ambulatory visits at a multispecialty cardiovascular center in Northern California from March 2019 to February 2020 (pre-COVID) and March 2020 to February 2021 (COVID). Telemedicine use increased from 3.5% of visits (1200/33,976) during the pre-COVID period to 63.0% (21,251/33,706) during the COVID period. Visit volumes were below pre-COVID levels from March to May 2020 but exceeded pre-COVID levels after June 2020, including when local COVID-19 cases peaked. Telemedicine use was above 75% of visits in all cardiology subspecialties in April 2020 and stabilized at rates ranging from over 95% in electrophysiology to under 25% in heart transplant and vascular medicine. From June 2020 to February 2021, subspecialties delivering a greater percentage of visits through telemedicine experienced larger increases in new patient visits (r = 0.81, p = 0.029). Telemedicine can be used to deliver a significant proportion of outpatient cardiovascular care though utilization varies across subspecialties. Higher rates of telemedicine adoption may increase access to care in cardiology clinics. [ABSTRACT FROM AUTHOR]

The present study focuses on recovery and removal of phosphate in the form of hydroxyapatite (HAP) from a phosphate-rich secondary-treated effluents. Synthesis of HAP has been done at different operating parameters and statistical analysis was carried out using response surface methodology (RSM). Initial PO43−−P concentration (mg/L), pH, and stirring speed (rpm) have been used as the input parameters for the RSM process. Optimization and interaction between the factors (initial PO43−−P concentration, pH, and rpm) were performed using the Box-Behnken design (BBD) of RSM. The model obtained from the RSM-based BBD statistical study has given pH: 12, PO43−−P initial concentration: 400 mg/L, and rpm: 100 as optimized parameters for the synthesis of HAP. Maximum removal of 79% phosphate removal/recovery was achieved (as HAP) in this study for the experimental runtime of 3.5 h. The effect of pH, PO43−−P initial concentration and stirring speed on HAP formation/phosphate removal were also briefly discussed. ANOVA and the fit statistics generated for the model has identified that the model is significant. The validation study conducted using both synthetically prepared and secondary-treated effluent revealed their reasonable agreement with the predicted results (less error). Scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX) characterization was performed for the HAP produced in this to discover the morphology and elemental composition. [ABSTRACT FROM AUTHOR]