Measurement and Characterization of Rotational Errors of Aerostatic Bearings in Subnanometer Accuracy.

Measuring the running accuracy of aerostatic bearings is challenging because of the high-precision requirements in rotational motion. This paper presents an ultra-high precision measurement method for aerostatic bearings using atomic force microscopy (AFM) as the displacement sensor. The Donaldson reversal method was used to separate the artifact form errors from the measurement results. A measurement system was developed with the integration of an AFM module. The effects of sensor nonlinearity, environmental noise, and structural vibration on the measurement results were effectively suppressed in the system. The experimental results show that the measurement achieves up to subnanometer accuracy.

A Review of In Situ Defect Detection and Monitoring Technologies in Selective Laser Melting.

The additive manufacturing (AM) technique has received considerable industrial attention, as it is capable of producing complex functional parts in the aerospace and defense industry. Selective laser melting (SLM) technology is a relatively mature AM process that can manufacture complex structures both directly and efficiently. However, the quality of SLM parts is affected by many factors, resulting in a lack of repeatability and stability of this method. Therefore, several common and advanced in situ monitoring as well as defect detection methods are utilized to improve the quality and stability of SLM processes. This article aims at documenting the various defects that occurred in SLM processes and their influences on the final parts. Various types of in situ monitoring and defect detection methods and their applications are reviewed, and their integrations with the SLM processes are also discussed.

Comparative Effectiveness and Safety of Direct Oral Anticoagulants Versus Warfarin Among Adults With Cancer and Atrial Fibrillation.

BACKGROUND: While clinical guidelines recommend direct-acting oral anticoagulants (DOAC) over warfarin to treat isolated nonvalvular atrial fibrillation, guidelines are silent regarding nonvalvular atrial fibrillation treatment among individuals with cancer, reflecting the paucity of evidence in this setting. We quantified relative risk of ischemic stroke or systemic embolism and major bleeding (primary outcomes), and all-cause and cardiovascular death (secondary outcomes) among older individuals with cancer and nonvalvular atrial fibrillation comparing DOACs and warfarin. METHODS: This retrospective cohort study used Surveillance, Epidemiology, and End Results cancer registry and linked US Medicare data from 2010 through 2016, and included individuals diagnosed with cancer and nonvalvular atrial fibrillation who newly initiated DOAC or warfarin. We used inverse probability of treatment weighting to control confounding. We used competing risk regression for primary outcomes and cardiovascular death, and Cox proportional hazard regression for all-cause death. RESULTS: Among 7675 individuals included in the cohort, 4244 (55.3%) received DOACs and 3431 (44.7%) warfarin. In the inverse probability of treatment weighting analysis, there was no statistically significant difference among DOAC and warfarin users in the risk of ischemic stroke or systemic embolism (1.24 versus 1.19 events per 100 person-years, adjusted hazard ratio 1.41 [95% CI, 0.92-2.14]), major bleeding (3.08 versus 4.49 events per 100 person-years, adjusted hazard ratio 0.90 [95% CI, 0.70-1.17]), and cardiovascular death (1.88 versus 3.14 per 100 person-years, adjusted hazard ratio 0.82 [95% CI, 0.59-0.1.13]). DOAC users had significantly lower risk of all-cause death (7.09 versus 13.3 per 100 person-years, adjusted hazard ratio 0.81 [95% CI, 0.69-0.94]) compared to warfarin users. CONCLUSIONS: Older adults with cancer and atrial fibrillation exposed to DOACs had similar risks of stroke and systemic embolism and major bleeding as those exposed to warfarin. Relative to warfarin, DOAC use was associated with a similar risk of cardiovascular death and a lower risk of all-cause death.

Development and Validation of the Summary Elixhauser Comorbidity Score for Use With ICD-10-CM-Coded Data Among Older Adults.

BACKGROUND: Older adults have many comorbidities contributing to mortality. OBJECTIVE: To develop a summary Elixhauser (S-Elixhauser) comorbidity score to predict 30-day, in-hospital, and 1-year mortality in older adults using the 38 comorbidities operationalized by the Agency for Healthcare Research and Quality (AHRQ). DESIGN: Retrospective cohort study. SETTING: Medicare beneficiaries from 2017 to 2019. PATIENTS: Persons hospitalized in 2018 (n = 899 844) and 3 disease-specific hospitalized cohorts. MEASUREMENTS: Weights were derived for 38 comorbidities to predict 30-day, in-hospital, and 1-year mortality. The S-Elixhauser score was internally validated and calibrated. Individual Elixhauser comorbidity indicators (38 comorbidities), the modified application of the AHRQ-derived Elixhauser summary score, the Charlson comorbidity indicators (17 comorbidities), and the Charlson summary score were externally validated. The c-statistic was used to evaluate discrimination of a comorbidity score model. RESULTS: The S-Elixhauser score was well calibrated and internally validated, with a c-statistic of 0.705 (95% CI, 0.703 to 0.707) in predicting 30-day mortality, 0.654 (CI, 0.651 to 0.657) for in-hospital mortality, and 0.743 (CI, 0.741 to 0.744) for 1-year mortality. In external validation of other comorbidity indices for 30-day mortality, the c-statistic was 0.711 (CI, 0.709 to 0.713) for the individual Elixhauser comorbidity indicators, 0.688 (CI, 0.686 to 0.690) for the AHRQ Elixhauser score, 0.696 (CI, 0.694 to 0.698) for the Charlson comorbidity indicators, and 0.690 (CI, 0.688 to 0.693) for the Charlson summary score. In 3 disease-specific populations, the discrimination of the S-Elixhauser score in predicting 30-day mortality ranged from 0.657 to 0.732. LIMITATION: Validation of the S-Elixhauser comorbidity score and head-to-head comparison with other comorbidity scores in an external population are needed to evaluate comparative performance. CONCLUSION: The S-Elixhauser comorbidity score is well calibrated and internally validated but its advantage over the AHRQ Elixhauser and Charlson summary scores is unclear. PRIMARY FUNDING SOURCE: National Institute on Aging.

Use of oral anticoagulants among individuals with cancer and atrial fibrillation in the United States, 2010-2016.

BACKGROUND: Anticoagulation among patients with cancer and atrial fibrillation is challenging due to elevated risk of bleeding and stroke. We characterized use of oral anticoagulants among patients with cancer and non-valvular atrial fibrillation (NVAF). METHODS: We used Surveillance, Epidemiology, and End Results (SEER)-Medicare data and included patients with cancer aged ≥66 years with an incident diagnosis of NVAF from 2010 to 2016. We used a Cox proportional hazard model and multivariable logistic regression to identify factors associated with anticoagulant use versus no use and direct oral anticoagulants (DOACs) versus warfarin use, respectively. RESULTS: Of 27,702 patients with cancer and NVAF, 4469 (16.1%) used DOACs and 3577 (12.9%) used warfarin. Among 8046 anticoagulant users, DOACs use increased from 21.8% in 2011 to 76.2% in 2016, with a corresponding decline in warfarin use from 78.2% to 23.8%. Nearly 7 out of 10 patients with cancer and NVAF did not initiate anticoagulation in 2016. Anticoagulant use was more likely among those with higher CHA2DS2-VASc scores (hazard ratio [HR] 1.55, 95% confidence interval [CI] 1.27-1.90 for score ≥6 vs. 1) or with lower HAS-BLED scores (HR 1.96, 95% CI 1.67-2.30 for score 1 vs. ≥6). Among anticoagulant users, DOAC use was less likely than warfarin in those with higher CHA2DS2-VASc scores (odds ratio [OR] 0.53, 95% CI 0.33-0.84 for score ≥6 vs. 1). CONCLUSIONS: Nearly 7 out of 10 patients with cancer and NVAF did not receive anticoagulation. Use of DOACs increased from 2010 to 2016, with a corresponding decline in warfarin use. DOACs are used less than warfarin among those at higher risk of stroke.

Use of Hydroxychloroquine, Remdesivir, and Dexamethasone Among Adults Hospitalized With COVID-19 in the United States : A Retrospective Cohort Study.

BACKGROUND: Relatively little is known about the use patterns of potential pharmacologic treatments of COVID-19 in the United States. OBJECTIVE: To use the National COVID Cohort Collaborative (N3C), a large, multicenter, longitudinal cohort, to characterize the use of hydroxychloroquine, remdesivir, and dexamethasone, overall as well as across individuals, health systems, and time. DESIGN: Retrospective cohort study. SETTING: 43 health systems in the United States. PARTICIPANTS: 137 870 adults hospitalized with COVID-19 between 1 February 2020 and 28 February 2021. MEASUREMENTS: Inpatient use of hydroxychloroquine, remdesivir, or dexamethasone. RESULTS: Among 137 870 persons hospitalized with confirmed or suspected COVID-19, 8754 (6.3%) received hydroxychloroquine, 29 272 (21.2%) remdesivir, and 53 909 (39.1%) dexamethasone during the study period. Since the release of results from the RECOVERY (Randomised Evaluation of COVID-19 Therapy) trial in mid-June, approximately 78% to 84% of people who have had invasive mechanical ventilation have received dexamethasone or other glucocorticoids. The use of hydroxychloroquine increased during March 2020, peaking at 42%, and started declining by April 2020. By contrast, remdesivir and dexamethasone use gradually increased over the study period. Dexamethasone and remdesivir use varied substantially across health centers (intraclass correlation coefficient, 14.2% for dexamethasone and 84.6% for remdesivir). LIMITATION: Because most N3C data contributors are academic medical centers, findings may not reflect the experience of community hospitals. CONCLUSION: Dexamethasone, an evidence-based treatment of COVID-19, may be underused among persons who are mechanically ventilated. The use of remdesivir and dexamethasone varied across health systems, suggesting variation in patient case mix, drug access, treatment protocols, and quality of care. PRIMARY FUNDING SOURCE: National Center for Advancing Translational Sciences; National Heart, Lung, and Blood Institute; and National Institute on Aging.

Risk of Hospitalization and Death Associated With Pimavanserin Use in Older Adults With Parkinson Disease.

BACKGROUND AND OBJECTIVES: To determine the risk of hospitalization and death associated with pimavanserin use. METHODS: We conducted a retrospective cohort study of adults 65 years and older with Parkinson disease between November 1, 2015, and December 31, 2018, using an administrative dataset on residents of Medicare-certified long-term care facilities and linked Medicare claims data. Propensity score-based inverse probability of treatment weighting (IPTW) was used to balance pimavanserin users and nonusers on 24 baseline characteristics. Fine-Gray competing risk and Cox proportional hazards regression models were used to estimate the risk of hospitalization and death up to 1 year, respectively. RESULTS: The study cohort included 2,186 pimavanserin users and 18,212 nonusers. There was a higher risk of 30-day hospitalization with pimavanserin use vs nonuse (IPTW-adjusted hazard ratio [aHR] 1.24, 95% confidence intervals [CI] 1.06-1.43). There was no association of pimavanserin use with 90-day hospitalization (aHR 1.10, CI 0.99-1.24) or with 30-day mortality (aHR 0.76, CI 0.56-1.03). Pimavanserin use vs nonuse was associated with increased 90-day mortality (aHR 1.20, CI 1.02-1.41) that persisted after 180 days (aHR 1.28, CI 1.13-1.45) and 1 year (aHR 1.56, CI 1.42-1.72). DISCUSSION: Pimavanserin use vs nonuse in older adults was associated with an increased risk of hospitalization at 1 month of initiation and a higher risk of death for up to 1 year following initiation. These findings, in a large real-world cohort within long-term care facilities, may help to inform decisions regarding its risk/benefit balance among patients with Parkinson disease. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that in patients with Parkinson disease who are 65 or older and residing in Medicare-certified long-term care facilities, pimavanserin is associated with an increased risk of 30-day hospitalization and higher 90-, 180-, and 365-day mortality.

Comparative Efficacy of Commercial Liquid and Mat-Type Electric Vaporizer Insecticides Against Asian Tiger Mosquito (Diptera: Culicidae).

Mat and liquid-type electric insecticide vaporizers continuously emit insecticides into the surrounding air. Because both the target insects, mostly mosquitoes, and humans are exposed to those insecticides, it is crucial to understand and monitor their deposition and spatial distribution in treated areas. In the current study, we examined the evaporation of insecticides from seven commercial liquid and mat vaporizers and measured their knock-down and insecticidal activity against the adult females of the Asian tiger mosquito, Aedes albopictus (Skuse). Electric vaporizers from three manufactures had differences in their heaters and active ingredients. Most had continued evaporation during hourly and daily monitoring; however, some liquid vaporizers failed to continue emission to their designated end periods. Overall, mosquitoes located at the upper position in a Peet-Grady chamber and in a field-simulation room exhibited faster knock-down activity than did mosquitoes in other areas, indicating that the insecticides accumulated on the ceiling area. Although most of mat and liquid vaporizers had <60 min of average KT90 values when tested in the Peet-Grady chamber (1.8 × 1.8 × 1.8 m), they failed to have any knock-down in 2 h of observation in the field-simulation room (6.8 × 3.4 × 2.7 m) but showed 72. 8 ± 11.7% and 56. 7 ± 7.3% knock-down in the mat and liquid vaporizers, respectively, in 3 h of operation. Further study will be required to examine whether this relatively limited efficacy can be compensated by other physiological and behavioral effects, including disruption in host-seeking or blood-sucking activities.

Efficacy of Seven Commercial Household Aerosol Insecticides and Formulation-Dependent Toxicity Against Asian Tiger Mosquito (Diptera: Culicidae).

For the indoor and outdoor pest controls, various types of insecticide formulations are available including aerosols, sprays, electric vaporizers, mosquito coils, and traps. In the present study, the insecticidal activity of aerosols, the most commonly used formulation of household insecticides for mosquito control, against Aedes albopictus (Skuse) was assessed using seven commercial products and some attributes which can affect the efficacy of aerosol were investigated as well. The products had difference in their chemical composition of active ingredients, propellant/liquid phase ratios, solvent types, and nozzle orifice sizes, and these characteristics seem to affect the overall insecticidal activity. In general, solvent type dominantly determined the insecticidal activity, where four products in oil-based solvent system showed greater mortality (97.5% in average) than water-based aerosols (38.3% in average) against the mosquitoes located at the far side of the test chamber. The contribution of solvent type and nozzle orifice size were further examined with the sample aerosols, and the orifice size were determined more influential to the spray distance. Regardless of solvent types, the sample products attached to a bigger actuator (0.96 mm in diameter) showed greater knock-down activity (>98%) than the smaller ones (0.48 mm, 62.5% in average) to the back panel in the chamber. On the other hand, solvent system significantly affected the residual activity, as the oil-based and water-based aerosols showed 2.3- and 4.8-fold decrease in KT50 values, respectively, between 1 and 10 min after the spray.