A multicentre outcome analysis to define global benchmarks for donation after circulatory death liver transplantation.

BACKGROUND & AIMS: The concept of benchmarking is established in the field of transplant surgery; however, benchmark values for donation after circulatory death (DCD) liver transplantation are not available. Thus, we aimed to identify the best possible outcomes in DCD liver transplantation and to propose outcome reference values. METHODS: Based on 2,219 controlled DCD liver transplantations, collected from 17 centres in North America and Europe, we identified 1,012 low-risk, primary, adult liver transplantations with a laboratory MELD score of ≤20 points, receiving a DCD liver with a total donor warm ischemia time of ≤30 minutes and asystolic donor warm ischemia time of ≤15 minutes. Clinically relevant outcomes were selected and complications were reported according to the Clavien-Dindo-Grading and the comprehensive complication index (CCI). Corresponding benchmark cut-offs were based on median values of each centre, where the 75th-percentile was considered. RESULTS: Benchmark cases represented between 19.7% and 75% of DCD transplantations in participating centres. The 1-year retransplant and mortality rates were 4.5% and 8.4% in the benchmark group, respectively. Within the first year of follow-up, 51.1% of recipients developed at least 1 major complication (≥Clavien-Dindo-Grade III). Benchmark cut-offs were ≤3 days and ≤16 days for ICU and hospital stay, ≤66% for severe recipient complications (≥Grade III), ≤16.8% for ischemic cholangiopathy, and ≤38.9 CCI points 1 year after transplant. Comparisons with higher risk groups showed more complications and impaired graft survival outside the benchmark cut-offs. Organ perfusion techniques reduced the complications to values below benchmark cut-offs, despite higher graft risk. CONCLUSIONS: Despite excellent 1-year survival, morbidity in benchmark cases remains high. Benchmark cut-offs targeting morbidity parameters offer a valid tool to assess the protective value of new preservation technologies in higher risk groups and to provide a valid comparator cohort for future clinical trials. LAY SUMMARY: The best possible outcomes after liver transplantation of grafts donated after circulatory death (DCD) were defined using the concept of benchmarking. These were based on 2,219 liver transplantations following controlled DCD donation in 17 centres worldwide. Donor and recipient combinations with higher risk had significantly worse outcomes. However, the use of novel organ perfusion technology helped high-risk patients achieve similar outcomes as the benchmark cohort.

Longitudinal participation in delivery and payment reform programs among US Primary Care Organizations.

OBJECTIVE: To assess longitudinal primary care organization participation patterns in large-scale reform programs and identify organizational characteristics associated with multiprogram participation. DATA SOURCES: Secondary data analysis of national program participation data over an eight-year period (2009-2016). STUDY DESIGN: We conducted a retrospective, observational study by creating a unique set of data linkages (including Medicare and Medicaid Meaningful Use and Medicare Shared Savings Program Accountable Care Organization (MSSP ACO) participation from CMS, Patient-Centered Medical Home (PCMH) participation from the National Committee for Quality Assurance, and organizational characteristics) to measure longitudinal participation and identify what types of organizations participate in one or more of these reform programs. We used multivariate models to identify organizational characteristics that differentiate those that participate in none, one, or two-to-three programs. DATA EXTRACTION METHODS: We used Medicare claims to identify organizations that delivered primary care services (n = 56 ,287) and then linked organizations to program participation data and characteristics. PRINCIPAL FINDINGS: No program achieved more than 50% participation across the 56,287 organizations in a given year, and participation levels flattened or decreased in later years. 36% of organizations did not participate in any program over the eight-year study period; 50% participated in one; 13% in two; and 1% in all three. 14.31% of organizations participated in five or more years of Meaningful Use while 3.84% of organizations participated in five years of the MSSP ACO Program and 0.64% participated in at least five years of PCMH. Larger organizations, those with younger providers, those with more primary care providers, and those with larger Medicare patient panels were more likely to participate in more programs. CONCLUSIONS AND RELEVANCE: Primary care transformation via use of voluntary programs, each with their own participation requirements and approach to incentives, has failed to broadly engage primary care organizations. Those that have chosen to participate in multiple programs are likely those already providing high-quality care.

Artificial intelligence to predict in-hospital mortality using novel anatomical injury score.

The aim of the study is to develop artificial intelligence (AI) algorithm based on a deep learning model to predict mortality using abbreviate injury score (AIS). The performance of the conventional anatomic injury severity score (ISS) system in predicting in-hospital mortality is still limited. AIS data of 42,933 patients registered in the Korean trauma data bank from four Korean regional trauma centers were enrolled. After excluding patients who were younger than 19 years old and those who died within six hours from arrival, we included 37,762 patients, of which 36,493 (96.6%) survived and 1269 (3.4%) deceased. To enhance the AI model performance, we reduced the AIS codes to 46 input values by organizing them according to the organ location (Region-46). The total AIS and six categories of the anatomic region in the ISS system (Region-6) were used to compare the input features. The AI models were compared with the conventional ISS and new ISS (NISS) systems. We evaluated the performance pertaining to the 12 combinations of the features and models. The highest accuracy (85.05%) corresponded to Region-46 with DNN, followed by that of Region-6 with DNN (83.62%), AIS with DNN (81.27%), ISS-16 (80.50%), NISS-16 (79.18%), NISS-25 (77.09%), and ISS-25 (70.82%). The highest AUROC (0.9084) corresponded to Region-46 with DNN, followed by that of Region-6 with DNN (0.9013), AIS with DNN (0.8819), ISS (0.8709), and NISS (0.8681). The proposed deep learning scheme with feature combination exhibited high accuracy metrics such as the balanced accuracy and AUROC than the conventional ISS and NISS systems. We expect that our trial would be a cornerstone of more complex combination model.

The Path Forward: Using Metrics to Promote Equitable Work Environments.

Women continue to be underrepresented in medicine, especially in senior leadership positions, and they experience challenges related to gender bias and sexual harassment. Women who are members of multiple groups that experience marginalization, including, for example, women who are American Indian, Alaskan native, indigenous, Black, or Hispanic, face a compounded challenge. In this article, we explore how institutions and professional organizations in medicine can use metrics to better understand the structural disparities that create and promote gender inequity in the work environment and how to employ these metrics to track progress in narrowing these gaps. Examples in health care (clinical medicine, scientific organizations, scientific publishing), business, and law are used to illustrate how impactful metrics can promote accountability when coupled with transparent reporting.

Assessment of Benchmark Dose in BEAS-2B Cells by Evaluating the Cell Relative Viability with Particulates in Motorcycle Exhaust via the Air-liquid Interface Exposure.

OBJECTIVE: This study aimed to use an air-liquid interface (ALI) exposure system to simulate the inhalation exposure of motorcycle exhaust particulates (MEPs) and then investigate the benchmark dose (BMD) of MEPs by evaluating cell relative viability (CRV) in lung epithelial BEAS-2B cells. METHODS: The MEPs dose was characterized by measuring the number concentration (NC), surface area concentration (SAC), and mass concentration (MC). BEAS-2B cells were exposed to MEPs at different concentrations via ALI and CRV was determined using Cell Counting Kit (CCK-8) assay. BMD software was applied to calculate BMD and the lower limit of benchmark dose (BMDL) according to Akaike Information Coefficient (AIC), with P-value based on Hill, Linear, Polynomial, and Power model. RESULTS: Our results reveal that BMD of NC and SAC were estimated by the best-fitting Hill model, while MC was estimated by Polynomial model. The BMDL for CRV following ALI exposure to MEPs were as follows: 364.2#/cm 3 for NC; 0.662 × 10 7 nm 2/cm 3 for SAC; and 0.278 µg/m 3 for MC. CONCLUSION: These results indicate that MEPs exposure via ALI system induces a dose-dependent decrease of CRV and provides the potential exposure threshold of MEPs in a lung cell model.

Benchmarking Oxford Nanopore read assemblers for high-quality molluscan genomes.

Choosing the optimum assembly approach is essential to achieving a high-quality genome assembly suitable for comparative and evolutionary genomic investigations. Significant recent progress in long-read sequencing technologies such as PacBio and Oxford Nanopore Technologies (ONT) has also brought about a large variety of assemblers. Although these have been extensively tested on model species such as Homo sapiens and Drosophila melanogaster, such benchmarking has not been done in Mollusca, which lacks widely adopted model species. Molluscan genomes are notoriously rich in repeats and are often highly heterozygous, making their assembly challenging. Here, we benchmarked 10 assemblers based on ONT raw reads from two published molluscan genomes of differing properties, the gastropod Chrysomallon squamiferum (356.6 Mb, 1.59% heterozygosity) and the bivalve Mytilus coruscus (1593 Mb, 1.94% heterozygosity). By optimizing the assembly pipeline, we greatly improved both genomes from previously published versions. Our results suggested that 40-50X of ONT reads are sufficient for high-quality genomes, with Flye being the recommended assembler for compact and less heterozygous genomes exemplified by C. squamiferum, while NextDenovo excelled for more repetitive and heterozygous molluscan genomes exemplified by M. coruscus. A phylogenomic analysis using the two updated genomes with 32 other published high-quality lophotrochozoan genomes resulted in maximum support across all nodes, and we show that improved genome quality also leads to more complete matrices for phylogenomic inferences. Our benchmarking will ensure efficiency in future assemblies for molluscs and perhaps also for other marine phyla with few genomes available. This article is part of the Theo Murphy meeting issue 'Molluscan genomics: broad insights and future directions for a neglected phylum'.

Validating a generic cancer consumer quality index in eight European countries, patient reported experiences and the influence of cultural differences.

BACKGROUND: Taking patient centeredness into account is important in healthcare. The European Cancer Consumer Quality Index (ECCQI) is a validated tool for international benchmarking of patient experiences and satisfaction. This study aimed to further validate the ECCQI in larger and more uniform groups of high volume tumours such as breast and prostate cancer. A second objective was the verification of the influence of cultural factors of the country to determine its possible use in international benchmarking. METHODS: Data from two survey studies in eight European countries were combined. Socio-demographic correlations were analysed with Kruskall-Wallis and Mann-Whitney tests. Cronbach's alpha was calculated to validate internal consistency. Influences of masculinity (MAS), power distance (PD) and uncertainty avoidance (UA) were determined by linear regression analysis in a general model and subgroup models. RESULTS: A total of 1322 surveys were included in the analysis (1093 breast- and 348 prostate cancer patients). Cronbach's alpha was good (α ≥ 0.7) or acceptable (0.5 ≤ α ≤ 0.7) in 8 out of 9 questionnaire categories, except in the category 'Safety' (α = 0.305). Overall ECCQI scores ranged from 22.1 to 25.1 between countries on a 1-35 scale (categories had a 1-4 scale). In certain subcategories such as 'Organisation' (range 2.2 vs 3.0) and 'Supervision & Support' (range 3.0 vs 3.8) a large difference was observed between countries. Differences in 'Overall opinion' were however small: mean scores of 3.7 vs 3.9, whereas median scores were all the maximum of 4.0. Power distance was positively associated with higher patient satisfaction scores whereas Uncertainty avoidance was negatively associated with these scores. Masculinity was only associated with patient satisfaction scores in lower educated patients. We found the highest impact of culture on overall scores in Hungary and Portugal and the lowest in Romania. CONCLUSIONS: The ECCQI shows high internal consistency in all categories except 'Safety'. Especially in separate categories and overall ECCQI scores the questionnaire showed discriminative value. This study showed a positive correlation of power distance and a negative correlation for uncertainty avoidance in some countries. When using the ECCQI for international benchmarking these two dimensions of culture should be taken into account.

Validation of the Artificial Intelligence-Based Predictive Optimal Trees in Emergency Surgery Risk (POTTER) Calculator in Emergency General Surgery and Emergency Laparotomy Patients.

BACKGROUND: The Predictive Optimal Trees in Emergency Surgery Risk (POTTER) tool is an artificial intelligence-based calculator for the prediction of 30-day outcomes in patients undergoing emergency operations. In this study, we sought to assess the performance of POTTER in the emergency general surgery (EGS) population in particular. METHODS: All patients who underwent EGS in the 2017 American College of Surgeons NSQIP database were included. The performance of POTTER in predicting 30-day postoperative mortality, morbidity, and 18 specific complications was assessed using the c-statistic metric. As a subgroup analysis, the performance of POTTER in predicting the outcomes of patients undergoing emergency laparotomy was assessed. RESULTS: A total of 59,955 patients were included. Median age was 50 years and 51.3% were women. POTTER predicted mortality (c-statistic = 0.93) and morbidity (c-statistic = 0.83) extremely well. Among individual complications, POTTER had the highest performance in predicting septic shock (c-statistic = 0.93), respiratory failure requiring mechanical ventilation for 48 hours or longer (c-statistic = 0.92), and acute renal failure (c-statistic = 0.92). Among patients undergoing emergency laparotomy, the c-statistic performances of POTTER in predicting mortality and morbidity were 0.86 and 0.77, respectively. CONCLUSIONS: POTTER is an interpretable, accurate, and user-friendly predictor of 30-day outcomes in patients undergoing EGS. POTTER could prove useful for bedside counseling of patients and their families and for benchmarking of EGS care.

Editor's Choice - Optimal Threshold for the Volume-Outcome Relationship After Open AAA Repair in the Endovascular Era: Analysis of the International Consortium of Vascular Registries.

OBJECTIVE: As open abdominal aortic aneurysm (AAA) repair (OAR) rates decline in the endovascular era, the endorsement of minimum volume thresholds for OAR is increasingly controversial, as this may affect credentialing and training. The purpose of this analysis was to identify an optimal centre volume threshold that is associated with the most significant mortality reduction after OAR, and to determine how this reflects contemporary practice. METHODS: This was an observational study of OARs performed in 11 countries (2010 - 2016) within the International Consortium of Vascular Registry database (n = 178 302). The primary endpoint was post-operative in hospital mortality. Two different methodologies (area under the receiving operating curve optimisation and Markov chain Monte Carlo procedure) were used to determine the optimal centre volume threshold associated with the most significant mortality improvement. RESULTS: In total, 154 912 (86.9%) intact and 23 390 (13.1%) ruptured AAAs were analysed. The majority (63.1%; n = 112 557) underwent endovascular repair (EVAR) (OAR 36.9%; n = 65 745). A significant inverse relationship between increasing centre volume and lower peri-operative mortality after intact and ruptured OAR was evident (p < .001) but not with EVAR. An annual centre volume of between 13 and 16 procedures per year was associated with the most significant mortality reduction after intact OAR (adjusted predicted mortality < 13 procedures/year 4.6% [95% confidence interval 4.0% - 5.2%] vs. ≥ 13 procedures/year 3.1% [95% CI 2.8% - 3.5%]). With the increasing adoption of EVAR, the mean number of OARs per centre (intact + ruptured) decreased significantly (2010 - 2013 = 35.7; 2014 - 2016 = 29.8; p < .001). Only 23% of centres (n = 240/1 065) met the ≥ 13 procedures/year volume threshold, with significant variation between nations (Germany 11%; Denmark 100%). CONCLUSION: An annual centre volume of 13 - 16 OARs per year is the optimal threshold associated with the greatest mortality risk reduction after treatment of intact AAA. However, in the current endovascular era, achieving this threshold requires significant re-organisation of OAR practice delivery in many countries, and would affect provision of non-elective aortic services. Low volume centres continuing to offer OAR should aim to achieve mortality results equivalent to the high volume institution benchmark, using validated data from quality registries to track outcomes.

Clinical Practices in Head and Neck Cancer: A Speech-Language Pathologist Practice Pattern Survey.

OBJECTIVE: Clinical practices of speech-language pathologists (SLP) treating head and neck cancer (HNC) patients range widely despite literature trending toward best practices. This survey study was designed to identify current patterns and assess for gaps in clinical implementation of research evidence. METHOD: A web-based survey was distributed to SLPs via listserv and social media outlets. Descriptive statistics and group calculations were completed to identify trends and associations in responses. RESULTS: Of 152 received surveys, the majority of respondents were hospital-based (86%) and had greater than 5 years of experience (65%). There was group consensus for the use of prophylactic exercise programs (95%), recommendations for SLP intervention during HNC treatment (75%), and use of maintenance programs post-treatment (97%). Conversely, no group consensus was observed for use of pre-treatment swallow evaluations, frequency of service provision, and content of therapy sessions. Variation in clinical decision making was noted in use of prophylactic feeding tubes and number of patients taking nothing by mouth during treatment. No associations were found between years of experience and decision-making practices, nor were any associations found between practice setting and clinical decision making. CONCLUSION: Despite the growing body of literature outlining evidence-based treatment practices for HNC patients, clinical practice patterns among SLPs continue to vary widely resulting in inconsistent patient care across practice settings. As compared to prior similar data, increased alignment with best practices was observed relative to early referrals, implementation of prophylactic intervention programs, and intervention with the SLP during the period of HNC treatment.

The use of benchmark dose uncertainty measurements for robust comparative potency analyses.

The Benchmark Dose (BMD) method is the favored approach for quantitative dose-response analysis where uncertainty measurements are delineated between the upper (BMDU) and lower (BMDL) confidence bounds, or confidence intervals (CIs). Little has been published on the accurate interpretation of uncertainty measurements for potency comparative analyses between different test conditions. We highlight this by revisiting a previously published comparative in vitro genotoxicity dataset for human lymphoblastoid TK6 cells that were exposed to each of 10 clastogens in the presence and absence (+/-) of low concentration (0.25%) S9, and scored for p53, γH2AX and Relative Nuclei Count (RNC) responses at two timepoints (Tian et al., 2020). The researchers utilized BMD point estimates in potency comparative analysis between S9 treatment conditions. Here we highlight a shortcoming that the use of BMD point estimates can mischaracterize potency differences between systems. We reanalyzed the dose responses by BMD modeling using PROAST v69.1. We used the resulting BMDL and BMDU metrics to calculate "S9 potency ratio confidence intervals" that compare the relative potency of compounds +/- S9 as more statistically robust metrics for comparative potency measurements compared to BMD point estimate ratios. We performed unsupervised hierarchical clustering that identified four S9-dependent groupings: high and low-level potentiation, no effect, and diminution. This work demonstrates the importance of using BMD uncertainty measurements in potency comparative analyses between test conditions. Irrespective of the source of the data, we propose a stepwise approach when performing BMD modeling in comparative potency analyses between test conditions.

Utilisation of the 2019 IWGDF diabetic foot infection guidelines to benchmark practice and improve the delivery of care in persons with diabetic foot infections.

AIMS: To utilise the 2019 International Working Group on the Diabetic Foot (IWGDF) - diabetic foot infection (DFI) guidelines as an audit tool for clinical practice in patients with diabetes attending a High-Risk Foot Service. METHODS: Data from 93 consecutive patients were collected over a 19-month period in patients attending a High-Risk Foot Service. The diagnosis and management of each patient in the sample were compared against the 2019 IWGDF DFI guidelines, grouped into four categories: Diagnosis, Microbiology, Treatment of soft tissue infection, and Surgical treatment and osteomyelitis. Deficits in performance were recorded using the recommendations as a benchmark standard. RESULTS: There were 109 DFI events. Nineteen (63%) of the recommendations were met, 7 (24%) were partially met, and four (13%) recommendations were not met. Fourteen of the sample had no documented requests for full blood counts. Tissue was obtained for culture in 32 (29%) of the sample. No percutaneous bone biopsies were performed. Only 13 (28%) patients had intraoperative bone specimens sent for culture and sensitivities, with no bone specimens sent for histopathology. Modification of antibiotic therapy following available culture results was low, occurring in 12 out of 63 possible occasions (19%). The duration of antibiotic regimens in PEDIS 2 infections and osteomyelitis was greater than that recommended. CONCLUSIONS: Utilising the IWGDF DFI guidelines to benchmark clinical practice is a useful tool to identify gaps in clinical performance or service delivery and may help to improve patient care.

National Trends in Daily Ambulatory Electronic Health Record Use by Otolaryngologists.

OBJECTIVE: Since their development in the 1970s electronic health records (EHRs) are now nearly ubiquitous. This study aims to characterize the daily interactions of otolaryngology providers with EHRs. METHODS: This study was a cross-sectional review of provider efficiency profile (PEP) data, as collected by a major EHR vendor. Participating institutions had 6 months of de-identified PEP data reviewed starting January 1, 2019. PEP data is generated for providers with scheduled patients, both attendings and advanced practice providers (APPs). Time metrics are recorded when a provider is interacting with the EHR including a 5-second time-out for inactivity. RESULTS: Data on 269 otolaryngologists and 29 APPs from 10 institutions were evaluated. On scheduled ambulatory clinic days attendings spent 70 ± 36 (mean ± standard deviation) min interacting in the EHR versus 108 ± 46 min for APPs. Of the daily EHR time, mean time in notes, clinical review, in basket, orders, and schedule were 30.1 ± 19.4, 9.6 ± 6.1, 7.3 ± 5.8, and 5.8 ± 7.6 min, respectively. Per patient visit, median (interquartile range) time in notes, clinical review, and orders were 3.19 (2.2-4.9), 1.14 (0.63-1.8), and 0.70 (0.47-1.05) min, respectively. Mean progress note length was 4638 ± 2143 characters. CONCLUSION: Otolaryngology providers spend a meaningful portion of their clinic day interacting with the EHR. PEP data may provide means to target interventions and a metric to measure the impact of those interventions on provider EHR efficiency. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:975-981, 2021.

Continued improvement in morbidity reduction in extremely premature infants.

OBJECTIVE: Provide a progress report updating our long-term quality improvement collaboration focused on major morbidity reduction in extremely premature infants 23-27 weeks. METHODS: 10 Vermont Oxford Network (VON) neonatal intensive care units (NICUs) (the POD) sustained a structured alliance: (A) face-to-face meetings, site visits and teleconferences, (B) transparent process and outcomes sharing, (C) utilisation of evidence-based potentially better practice toolkits, (D) family integration and (E) benchmarking via a composite mortality-morbidity score (Benefit Metric). Morbidity-specific toolkits were employed variably by each NICU according to local priorities. The eight major VON morbidities and the risk-adjusted Benefit Metric were compared in two epochs 2010-2013 versus 2014-2018. RESULTS: 5888 infants, mean (SD) gestational age 25.8 (1.4) weeks, were tracked. The POD Benefit Metric significantly improved (p=0.03) and remained superior to the aggregate VON both epochs (p<0.001). Four POD morbidities significantly improved through 2018 - chronic lung disease (48%-40%), discharge weight <10th percentile (32%-22%), any late infection (19%-17%) and periventricular leukomalacia (4%-2%). In epoch 2, 34% of survivors had none of the eight major morbidities, while 36% had just one. Mortality did not change. CONCLUSIONS: Inter-NICU collaboration, process and outcomes sharing and potentially better practice toolkits sustain improvement in 23-27 week morbidity rates, notably chronic lung disease, extrauterine growth restriction and the lowest zero-or-one major morbidity rate reported by a quality improvement collaboration. Unrevealed biological and cultural variables affect morbidity rates, countless remain unmeasured, thus duplication to other quality improvement groups is challenging. Understanding intensive care as innumerable interactions and constant flux that defy convenient linear constructs is fundamental.

Age disparities in stage-specific colon cancer survival across seven countries: An International Cancer Benchmarking Partnership SURVMARK-2 population-based study.

We sought to understand the role of stage at diagnosis in observed age disparities in colon cancer survival among people aged 50 to 99 years using population-based cancer registry data from seven high-income countries: Australia, Canada, Denmark, Ireland, New Zealand, Norway and the United Kingdom. We used colon cancer incidence data for the period 2010 to 2014. We estimated the 3-year net survival, as well as the 3-year net survival conditional on surviving at least 6 months and 1 year after diagnosis, by country and stage at diagnosis (categorised as localised, regional or distant) using flexible parametric excess hazard regression models. In all countries, increasing age was associated with lower net survival. For example, 3-year net survival (95% confidence interval) was 81% (80-82) for 50 to 64 year olds and 58% (56-60) for 85 to 99 year olds in Australia, and 74% (73-74) and 39% (39-40) in the United Kingdom, respectively. Those with distant stage colon cancer had the largest difference in colon cancer survival between the youngest and the oldest patients. Excess mortality for the oldest patients with localised or regional cancers was observed during the first 6 months after diagnosis. Older patients diagnosed with localised (and in some countries regional) stage colon cancer who survived 6 months after diagnosis experienced the same survival as their younger counterparts. Further studies examining other prognostic clinical factors such as comorbidities and treatment, and socioeconomic factors are warranted to gain further understanding of the age disparities in colon cancer survival.

Assessment of Benchmark Dose in BEAS-2B Cells by Evaluating the Cell Relative Viability with Particulates in Motorcycle Exhaust / 生物医学与环境科学（英文）

Objective@#This study aimed to use an air-liquid interface (ALI) exposure system to simulate the inhalation exposure of motorcycle exhaust particulates (MEPs) and then investigate the benchmark dose (BMD) of MEPs by evaluating cell relative viability (CRV) in lung epithelial BEAS-2B cells.@*Methods@#The MEPs dose was characterized by measuring the number concentration (NC), surface area concentration (SAC), and mass concentration (MC). BEAS-2B cells were exposed to MEPs at different concentrations @*Results@#Our results reveal that BMD of NC and SAC were estimated by the best-fitting Hill model, while MC was estimated by Polynomial model. The BMDL for CRV following ALI exposure to MEPs were as follows: 364.2#/cm @*Conclusion@#These results indicate that MEPs exposure

Quantifying intraherd cattle movement metrics: Implications for disease transmission risk.

There are a paucity of data quantifying on-farm management practices such as the frequency of intraherd cattle movements, use of consolidated or spatially fragmented grazing pastures, and duration of time cattle spend at grass with respect to biosecurity and disease transmission. Such movement dynamics are important when attempting to understand the maintenance of chronic infectious disease, such as bovine tuberculosis (bTB). We captured empirical data on daily cattle movements for a sample of eighteen farms throughout one complete grazing season (n = 18,988 grazing days) and assessed these attributes in relation to herd bTB risk. Dairy herds were stocked at significantly higher densities compared to beef production systems (6.6 animals/ha, 95 % confidence intervals (CI) 6.5-6.7 and 4.1 animals/ha, 95 %CI 4.1 - 4.1 respectively, p < 0.001). Most notably milking cows, were grazed at higher densities than other life stages (e.g. calves, heifers and bullocks) (p < 0.001) and experienced four times the number of movements between pastures. Beef cattle were more likely to be grazed across multiple (rather than single) fields (p < 0.001), with greater time spent on fragmented land away from the main/home farm (p < 0.001). None of the farm or herd attributes analysed (e.g. stocking density, frequency of movement, movement distances or land fragmentation) were associated with herd bovine tuberculosis (bTB) breakdowns during this study. However, there was a weak positive association between bTB breakdowns during the 3 years prior to the study and cattle movement distances (p = 0.05) and time spent on fragmented land (p = 0.08). After a bTB breakdown occurs, restrictions on animals moving out of these herds are implemented to control disease spread, yet we argue that more attention is needed on the role of intraherd grazing patterns in modelling disease transmission risk between herds.