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Identifying predictors of opioid overdose following release from prison is critical for opioid overdose prevention. We leveraged an individually linked, state-wide database from 2015–2020 to predict the risk of opioid overdose within 90 days of release from Massachusetts state prisons. We developed two decision tree modeling schemes: a model fit on all individuals with a single weight for those that experienced an opioid overdose and models stratified by race/ethnicity. We compared the performance of each model using several performance measures and identified factors that were most predictive of opioid overdose within racial/ethnic groups and across models. We found that out of 44,246 prison releases in Massachusetts between 2015–2020, 2237 (5.1%) resulted in opioid overdose in the 90 days following release. The performance of the two predictive models varied. The single weight model had high sensitivity (79%) and low specificity (56%) for predicting opioid overdose and was more sensitive for White non-Hispanic individuals (sensitivity = 84%) than for racial/ethnic minority individuals. Stratified models had better balanced performance metrics for both White non-Hispanic and racial/ethnic minority groups and identified different predictors of overdose between racial/ethnic groups. Across racial/ethnic groups and models, involuntary commitment (involuntary treatment for alcohol/substance use disorder) was an important predictor of opioid overdose. [ABSTRACT FROM AUTHOR]

When studying health risks across a large geographic region such as a state or province, researchers often assume that finer-resolution data on health outcomes and risk factors will improve inferences by avoiding ecological bias and other issues associated with geographic aggregation. However, coarser-resolution data (e.g., at the town or county-level) are more commonly publicly available and packaged for easier access, allowing for rapid analyses. The advantages and limitations of using finer-resolution data, which may improve precision at the cost of time spent gaining access and processing data, have not been considered in detail to date. We systematically examine the implications of conducting town-level mixed-effect regression analyses versus census-tract-level analyses to study sociodemographic predictors of COVID-19 in Massachusetts. In a series of negative binomial regressions, we vary the spatial resolution of the outcome, the resolution of variable selection, and the resolution of the random effect to allow for more direct comparison across models. We find stability in some estimates across scenarios, changes in magnitude, direction, and significance in others, and tighter confidence intervals on the census-tract level. Conclusions regarding sociodemographic predictors are robust when regions of high concentration remain consistent across town and census-tract resolutions. Inferences about high-risk populations may be misleading if derived from town- or county-resolution data, especially for covariates that capture small subgroups (e.g., small racial minority populations) or are geographically concentrated or skewed (e.g., % college students). Our analysis can help inform more rapid and efficient use of public health data by identifying when finer-resolution data are truly most informative, or when coarser-resolution data may be misleading. [ABSTRACT FROM AUTHOR]

A methodology for optimizing the inertial characteristics, propeller, battery capacity and PID (Proportional Integral Derivative) controller for propeller of an Autonomous Underwater Vehicle (AUV) is proposed in this paper. The AUV is launched at high speed in horizontal orientation, thereafter it pitches bow down and finally hovers at a particular desired water depth. The study involves both positively and negatively buoyant AUV. Four quadrant propeller open water model and quaternion are incorporated in the Maneuvering Modeling Group (MMG) type maneuvering model to make it suitable for 7 degree of freedom (DoF) dynamics. The bow down orientation is performed due to the inertial characteristics of the AUV, while the depth control maneuvering of the AUV is carried out by using PID controller for propeller revolutions. A cost function is proposed in terms of energy consumed and the distance traveled by AUV during the desired maneuver. The numeral value of cost function can be computed by carrying out numerical simulations. The numerical simulations can estimate when the AUV's propeller works in turbine mode. This information is useful for protecting the electric/electronic components of the AUV. • Study of positively and negatively buoyant AUV dynamics with four quadrant propeller. • Study of depth control maneuver for different operating speed using quaternion. • Optimization of gain coefficients of the PID controller for propeller revolution control. • Development of cost function for finding battery capacity. [ABSTRACT FROM AUTHOR]

Titanium alloys are of great demand in the aerospace and biomedical industries. Most the titanium products are either cast or sintered to required shape and finish machined to get the appropriate surface texture to meet the design requirements. Ti-6Al-4 V is often referred as work horse among the titanium alloys due to its heavy use in the aerospace industry. This paper is an attempt to investigate and improve the machining performance of Ti-6Al-4 V. Thin wall machining is an advance machining technique especially used in machining turbine blades which can be done both in a conventional way and using a special technique known as trochoidal milling. The experimental design consists of conducting trials using combination of cutting parameters such as cutting speed (vc), 90 and 120 m/min; feed/tooth (fz) of 0.25 and 0.35 mm/min; step over (ae) 0.3 and 0.2; at constant depth of cut (ap) 20 mm and using coolant. A preliminary assessment of machinability of Ti-6Al-4 V during thin wall machining using trochoidal milling is done. A correlation established using cutting force, surface texture and dimensional accuracy. [ABSTRACT FROM AUTHOR]

Abstract: Relatively less toxic and biodegradable ionic liquid [C8dabco]Br has been successfully used for the synthesis of quinoxaline and phthalazinetrione derivatives in an aqueous media. Recyclability of catalyst, high yields, use of environmentally benign aqueous media as solvent, simple product isolation and high atom economy are the noteworthy aspects of the protocols. [Copyright &y& Elsevier]

Bioresorbable polymer microparticles are widely used to provide long-lasting drug delivery in several chronic diseases. Having fine control over the physical properties of such microparticles can improve product reproducibility, performance and process efficiency. By using an ink-jet based droplet generator device, a new approach to microparticle manufacture was explored that uses an extremely rapid phase-separation to produce highly uniform, injectable microparticles from PLGA and a PLA/PLGA blend. To demonstrate the possible pharmaceutical applicability of the microparticle printing technique, the approved peptides ciclosporin A and octreotide were formulated, producing low-density microparticles that showed between sustained release over several months. The facile scale-up of the technique was demonstrated by using an array of 256 ink-jet nozzles, allowing over 1 million discrete particles per second to be produced. The new apparatus and methods described herein could be used across a wide range of biomaterials and therapeutic compounds. [ABSTRACT FROM AUTHOR]