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Geosynthetic clay liners (GCLs) are mostly used as flow barriers in landfills and waste containments due to their low hydraulic conductivity to prevent the leachate from reaching the environment. The self-healing and swell-shrink properties of soft clays (expansive soils) such as bentonite enable them as promising materials for the GCL core layers. However, it is important to modify their physico-chemical properties in order to overcome the functional limitations of GCL under different hydraulic conditions. In the present study, locally available black cotton soil (BCS) is introduced in the presence of an anionic polymer named carboxymethyl cellulose (CMC) as an alternative to bentonite to enhance the hydraulic properties of GCL under different compositions. The modified GCL is prepared by stitching the liner with an optimum percentage of CMC along with various percentages of BCS mixed with bentonite. Hydraulic conductivity tests were performed on the modified GCL using the flexi-wall permeameter. The results suggest that the lowest hydraulic conductivity of 4.58 × 10−10 m/s is obtained when 25% of BCS is blended with bentonite and an optimum 8% CMC and further addition of BCS results in the reduction of the hydraulic conductivity. HIGHLIGHTS Modification of bentonite with locally available black cotton soil and caboxymethyl cellulose polymer.; Enhancement of hydraulic performance of modified geosynthetic clay liner.; Sodium content is low in the modified bentonite beyond the optimum percentage of black cotton soil blended with carboxymethyl cellulose polymer.;

As the short- and long-term impacts of climate change are becoming more visible at smaller regional scales, frequent occurrence (absence) of erratic precipitation as well as water scarcity issues can be identified as reliable indicators for predicting meteorological droughts. A supervised declaration of meteorological drought based on available precipitation data requires an understanding of reliability and consistency of drought indices for appropriate severity classification. An attempt has been made in this study to critically evaluate the performance of six popular drought indices namely, Standardized Precipitation Index (SPI), China Z Index (CZI), Modified China Z Index (MCZI), Deciles Index (DI), Rainfall Anomaly Index (RAI), and Z-Score Index (ZSI) for four districts in Tamil Nadu falling under arid (Karur), semi-arid (Cuddalore), dry sub-humid (Kanyakumari) and moist sub-humid (Coimbatore) conditions based on 120 years of precipitation records. Results showed that the SPI and CZI provided similar quantification of drought events (about 18% of the total months) irrespective of their climatic considerations while ZSI and RAI resulted in overestimation of drought severity (about 30–47%). Based on the classification strategy adopted for the selected indices, a framework for drought vulnerability assessment is proposed in conjunction with the estimated drought severity classifications. HIGHLIGHTS An attempt is made in this study to critically evaluate the performance of six different drought indices.; SPI, CZI, MCZI, DI, RAI and ZSI are calculated for four districts in Tamil Nadu.; SPI and CZI provided similar quantification of drought events irrespective of the regional scale climatic considerations.; ZSI and RAI resulted in overestimation of drought severity.; A framework for the drought vulnerability assessment is provided.;

Aluminium alloy components are used in lightweight engineering applications and lack mechanical properties, wear resistance, and corrosion resistance. When hard reinforcement particulates are dispersed in the aluminium matrix alloy, aluminium matrix composites (AMCs) are formed. This new material exhibits enhanced properties such as better specific stiffness, specific strength, corrosion resistance, elastic modulus, wear resistance, and lightweight. AMCs have many favorable properties compared to their alloy and extensive applications. Especially, in the space industry, where weight reduction and an increase in modulus are prevalent, the strength-to-weight ratio is more important. This study focuses on the tribological, mechanical, and corrosion properties of Al 7075 metal matrix composites (MMCs) reinforced with one or more particulates such as aluminium oxide (Al2O3), boron carbide (B4C), titanium carbide (TiC), silicon carbide (SiC), titanium dioxide (TiO2), and titanium diboride (TiB2). In AMCs, the reinforcements are incorporated by either the solid or liquid metallurgy route. The study addresses the findings and shortcomings in the preparation of MMCs with reinforcements and their improvement in corrosion resistance, wear resistance, mechanical properties, and lower coefficient of thermal expansion than the Al 7075 base alloy. A comprehensive survey of reinforcement particulates in MMCs and their influences are outlined from the literature, encompassing recent research trends to enhance the structural properties.

Performance of green treatment systems such as adsorption to treat textile effluents often suffers lack of longevity and efficiency due to the presence of complex compounds of varying reactivity. There is scope for improving the operational efficiency of such processes using real-time monitoring systems. The present study aimed to evaluate the performance of an activated biosorbent prepared from the leaves of Acalypha indica for treating textile industry effluent by simulating process control with real-time monitoring. Batch experiments were performed with synthetic and real-time dye effluents to identify the optimum conditions (pH = 3.0, dosage = 1.0 g/L; time = 1 h) for the highest adsorption capacity (6 mg g−1 and 2 mg g−1). The evaluation of physical parameters suggested best fit for Freundlich isotherm model and pseudo-second-order kinetic model. The LabVIEW-based simulation control system enabled close monitoring of pH and temperature during the process. Based on the inputs, an alteration of initial pH has resulted in substantial reduction in chemical oxygen demand (COD) (73.91%), turbidity (52.43%) and total dissolved solids (TDS) (19.43%). The average incremental increase was highest for COD (45.80 ± 0.06%) compared to TDS (10.13 ± 0.06%) and turbidity (−1.74 ± 0.03%) for varying dosage (3 g to 11 g). The proposed framework for incorporating a process-control-based monitoring system can help to achieve better performance. HIGHLIGHTS Activated carbon produced from the leaves of Acalypha indica as a biosorbent.; Adsorption isotherm provides best fit with Freundlich model.; Adsorption kinetics indicate that the textile effluent follows pseudo-second-order kinetics.; LabVIEW has been used for the measurement of pH and temperature of the effluent.; Adjustment of the initial pH led to substantial reduction in the COD, TDS and turbidity.;

Carbon nanotubes (CNTs) and graphene, in particular, have been the subject of many recent studies since their discovery in the early 2000s. Because of their unusual properties, carbon nanotubes (CNTs) have piqued the interest of scientists across a wide range of disciplines. An Al matrix was reinforced with powder metallurgy-fabricated B4C and CNT composites. The nanocomposite aluminium matrix was examined for tribological behaviour, density, stiffness, and compressive strength before and after hot isostatic pressing (HIP). Scanning electron microscopy and TEM were used to analyze the carbon nanotubes and their hybrid counterparts (SEM). The density of nanocomposites was reduced by 38% without HIP but by 45% after it was added to the mixture. Hardness was also increased by 40%, but following HIP, the hardness rose to 67%. Before and after HIP, the compression strength increased by 39% and 60%, respectively. HIP improves the wear rate by 45%, and B4C and CNTs improve the coefficient of friction by 20% in all volume fractions but only by 48% in the case of nanocomposites.

Reservoirs are the major source of water supply in many localities for meeting the water demand of the people, and hence it is important to monitor the metal concentration of the water stored in such reservoirs for the benefit of the people in terms of drinking water and irrigation. The main objective of this study is to monitor the metal concentrations of Arsenic (As), Boron (B), Cadmium (Cd), Chromium (Cr), Copper (Cu), Iron (Fe), Nickel (Ni), Lead (Pb), Selenium (Se), and Zinc (Zn) in the water of the Amaravathi and Thirumoorthy reservoirs located in the Tiruppur district of the state of Tamil Nadu, India. Results indicate that the water collected from the Thirumoorthy reservoir is free from metal contamination while that from the Amaravathi reservoir has a marginal contamination of Fe concentration. Thus, the water stored in these reservoirs is suitable for drinking and irrigation purpose.

A synthetic cry2AX1 gene, consisting sequence of cry2Aa and cry2Ac genes, driven by green tissue specific rbcS promoter was used to develop insect resistant marker-free transgenic rice events. The gene of interest cry2AX1 and the selectable marker gene hpt were present in two independent T-DNAs of the Agrobacterium strain, C58C1. Seventy seven hygromycin and GUS positive T0 transgenic plants were recovered. Among them, 48 were found to be co-transformed with cry2AX1. The Cry2AX1 protein expression level in T0 transgenic events ranged from 0.027 to 0.110 μg/g of fresh leaf tissue. The toxicity level of Cry2AX1 protein was assessed through in vitro bioassay against target insects. The larval mortality ranged from 46.66 to 66.67 per cent against rice leaffolder (C. medinalis) while it ranged from 60 to 100 per cent against rice yellow stem borer (S. incertulas) in T0 transgenic plants. A marker free transgenic event, which expressed 0.043 μg/g of Cry2AX1 in fresh leaf tissue exhibited 45 and 55 per cent larval mortality against rice leaffolder and rice yellow stem borer, respectively in T2 generation.

Diversity analyses on ninety two genotypes of sesame using ten morphological characters were studied. Results indicated that ten clusters were formed wherein maximum inter cluster distance was observed between cluster IX and X (239.87). Simultaneously crossing of these 90 genotypes with Co-1 and TMV-5 was carried out. The 180 hybrids generated using two lines (CO 1 and TMV 5) with these 90 genotypes, upon evaluation, indicated five elite hybrids namely TMV 5 X bardur local (B)(217.49 percent), TMV 5 X bardur local (W) (198.38 percent), CO 1 x RT 172 (163.47 percent), TMV 5 x Rama (161.04 percent) and TMV 5 x MT-10-23-3 (155.57 percent) significantly yielded than the standard check TMV 7 and their male parents were found to be from the cluster I which were moderately divergent (19.09) among them.

Sorption is one of the key processes that plays a major role in the transport of contaminants in fractured porous media. Extensive studies have been conducted on sorption isotherms in fracture matrix coupled system but studies pertaining to sorption in fractured porous media with fracture–skin are very limited. In this study, a numerical model is developed for analysing the influence of sorption intensities on velocity, macro dispersion coefficient and dispersivity using the method of spatial moments. Implicit finite difference numerical technique has been used to solve the coupled non-linear governing equations. A varying grid is adopted at the fracture and skin interface to capture the mass transfer at the interface. Results suggest that the role of non-linear sorption is dominant in comparison with that of advection and dispersion in deciding the final relative concentration within the fracture. The role of sorption partition coefficients is not always enhancing the mixing phenomena which lead to dilution of solutes. Furthermore, the role of sorption partition coefficients is extremely sensitive in the sense that the resultant magnitude of effective dispersivity may either get enhanced or mitigated depending on the magnitude of sorption partition coefficients.

Metal Matrix composites (MMCs) has many excellent engineering properties like good strength to weight ratio, stiffness and increased wear resistance etc., These properties are the main requirements in aerospace, automotive industries and hence the MMCs are extensively used in these industries. This paper presents the detailed experimental study on cutting forces and surface roughness aspects in turning of 5% Graphite reinforced AZ91D Magnesium alloy metal matrix composite (AZ91D Magnesium alloy matrix + 5 % Graphite reinforcement). The stir casting process under inert atmosphere is followed for synthesis of the composite. The turning process is followed using Tungsten carbide cutting tool, in a lathe. The effect of machining parameters viz., cutting speed, feed rate and depth of cut, on the cutting forces and surface roughness (Ra) achieved during the machining are analysed and modelled through the response surface methodology (RSM). Study of effect of machining parameters and their interactions are carried out by using the surface, contour plots of RSM. The experimental result shows that the most significant machining parameter affecting surface roughness and cutting forces is cutting speed. The experimental results and predicted values are observed as in good agreement.

The workpiece produced by wire electrical discharge machining (WEDM) has the surface variations caused by simultaneous heating and cooling process during machining. The thermally affected layers have great effect on mechanical and metallurgical properties. It is not possible to achieve good surface finish (Ra) with a single pass. After the machining process few finishing passes have to be used to produce a better surface finish. In this paper an attempt is made to achieve maximum surface finish by using multi cutting passes in WEDM. The Metal Matrix Composite (MMC) workpieces were machined at one, two and three cutting passes and the Ra of the workpieces of MMC is measured. Field Emission Scanning Electron Microscopy (FESEM) picture is analyzed to study the white layer or recast layer and heat affected zone (HAZ) in the machined surface of the workpiece. By the experimental results, it is found that Ra value is reduced by increasing the number of cutting passes. In rough cutting pass the white layer is formed which increases the surface cracks and craters. In semi finish cutting passes the thickness of the white layer is reduced and it decreases the surface cracks and craters and in finish cutting pass the white layer is completely removed.

Vigna Δ1-pyrroline-5-carboxylate synthetase (P5CS) cDNA was transferred to chickpea (Cicer arietinum L.) cultivar Annigeri via Agrobacterium tumefaciens mediated transformation. Following selection on hygromycin and regeneration, 60 hygromycin-resistant plants were recovered. Southern blot analysis of five fertile independent lines of T0 and T1 generation revealed single and multiple insertions of the transgene. RT-PCR and Western blot analysis of T0 and T1 progeny demonstrated that the P5CS gene is expressed and produced functional protein in chickpea. T1 transgenic lines accumulated higher amount of proline under 250 mM NaCl compared to untransformed controls. Higher accumulation of Na+ was noticed in the older leaves but negligible accumulation in seeds of T1 transgenic lines as compared to the controls. Chlorophyll stability and electrolyte leakage indicated that proline overproduction helps in alleviating salt stress in transgenic chickpea plants. The T1 transgenics lines were grown to maturity and set normal viable seeds under continuous salinity stress (250 mM) without any reduction in plant yield in terms of seed mass.

Zeolitic Imidazolate (metal organic) Frameworks (ZIFs) and Prussian Blue Analogues (PBAs) are promising materials in electrochemical sensing due to their unique properties. In this study, a composite material comprising NiFe-PBA and ZIF-67 was synthesized and made to form a uniform layer onto a glassy carbon electrode (GCE) to enhance electrochemical performance for furazolidone (FZD) detection. The synthesized NiFe-PBA/ZIF-67 composite exhibited excellent sensitivity, selectivity, and stability towards FZD detection, with a low limit of detection (LOD). The electrochemical behaviour of FZD on the NiFe-PBA/ZIF-67/GCE electrode was investigated, revealing a diffusion-controlled process. Differential pulse voltammetry (DPV) analysis demonstrated the synergetic effect of the PBA/MOF core-shell structure in enhancing FZD electro-reduction. The sensor exhibited exceptional LOD of 0.007 μM. Selectivity studies confirmed the sensor's ability to distinguish FZD from potential interferents. Extensive evaluations demonstrated the sensor's reproducibility, repeatability, and long-term stability, affirming its practical utility. Real sample analysis further validated the sensor's excellent analytical capabilities in diverse matrices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Phototherapy based on photocatalytic semiconductor nanomaterials has received considerable attention for the cancer treatment. Nonetheless, intense efficacy for in vivo treatment is restricted by inadequate photocatalytic activity and visible light response., Methods: In this study, we designed a photocatalytic heterostructure using graphitic carbon nitride (g-C 3 N 4 ) and tin disulfide (SnS 2 ) to synthesize g-C 3 N 4 /SnS 2 heterostructure through hydrothermal process. Furthermore, Au nanoparticles were decorated in situ deposition on the surface of the g-C 3 N 4 /SnS 2 heterostructure to form g-C 3 N 4 /SnS 2 @Au nanoparticles., Results: The g-C 3 N 4 /SnS 2 @Au nanoparticles generated intense reactive oxygen species radicals under near-infrared (NIR) laser irradiation through photodynamic therapy (PDT) pathways (Type-I and Type-II). These nanoparticles exhibited enhanced photothermal therapy (PTT) efficacy with high photothermal conversion efficiency (41%) when subjected to 808 nm laser light, owing to the presence of Au nanoparticles. The in vitro studies have indicated that these nanoparticles can induce human liver carcinoma cancer cell (HepG2) apoptosis (approximately 80% cell death) through the synergistic therapeutic effects of PDT and PTT. The in vivo results demonstrated that these nanoparticles exhibited enhanced efficient antitumor effects based on the combined effects of PDT and PTT., Conclusion: The g-C 3 N 4 /SnS 2 @Au nanoparticles possessed enhanced photothermal properties and PDT effect, good biocompatibility and intense antitumor efficacy. Therefore, these nanoparticles could be considered promising candidates through synergistic PDT/PTT effects upon irradiation with NIR laser for cancer treatment., Competing Interests: The authors declare no known competing financial interests or personal relationships that could have influenced the work reported in this paper., (© 2024 Dash et al.)

A combination of therapeutic modalities in a single nanostructure is crucial for a successful cancer treatment. Synergistic photothermal therapy (PTT) can enhance the effects of chemodynamic therapy (CDT) and chemotherapy, which could intensify the therapeutic efficacy to induce cancer cell apoptosis. In this study, Fe and Mn on a zeolitic imidazolate framework (ZIF-8) (Fe/Mn-ZIF-8; FMZ) were synthesized through ion deposition. Furthermore, bismuth sulfide nanorods (Bi 2 S 3 NRs; BS NRs) were synthesized via a hydrothermal process and coated onto FMZ to generate the core-shell structure of the Bi 2 S 3 @FMZ nanoparticles (B@FMZ). Next, methotrexate (MTX) was loaded effectively onto the porous surface of ZIF-8 to form the B@FMZ/MTX nanoparticles. The Fenton-like reaction catalyzes Fe 2+ /Mn 2+ ions by decomposing H 2 O 2 in the tumor microenvironment, resulting in the formation of toxic hydroxyl radicals (·OH), which promotes the CDT effect of killing cancer cells. Furthermore, under 808 nm laser irradiation, these B@FMZ nanoparticles showed a strong PTT effect, owing to the presence of intense BS NRs as a photothermal agent. The B@FMZ nanoparticles exhibited a prominent drug release efficiency of 87.25% at pH 5.5 under near-infrared laser irradiation due to the PTT effect can promote the drug delivery performance. The B@FMZ nanoparticles were subjected to dual-modal imaging, guided magnetic resonance imaging, and X-ray computed tomography imaging. Both in vitro and in vivo results suggested that the B@FMZ/MTX nanoparticles exhibited enhanced antitumor effects through the combined therapeutic effects of PTT, CDT, and chemotherapy. Therefore, these nanoparticles exhibit good biocompatibility and are promising candidates for cancer treatment.

This research introduces a novel composite material, cobalt hydroxide/titanium dioxide (Co(OH) 2 /TiO 2 ), engineered for the detection of the fungicide carbendazim (CBZ) in environmental samples. A glassy carbon electrode (GCE) was modified with Co(OH) 2 /TiO 2 to create an electrochemical sensor capable of highly sensitive CBZ detection. Differential pulse voltammetry was utilized to quantify various CBZ concentrations, revealing that the Co(OH) 2 /TiO 2 -GCE sensor provided robust response signals across a concentration range from 0.039 μM to 2630.1 μM, with a detection limit of 0.007 μM. The sensor demonstrated notable stability, reproducibility, and selectivity towards CBZ, attributable to the synergistic effects of Co(OH) 2 /TiO 2 . Additionally, the Co(OH) 2 /TiO 2 -GCE sensor proved effective for analyzing CBZ in fruit and vegetable samples. Thus, this sensor presents significant potential for widespread application in environmental monitoring and food safety assessments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Learning, memorizing, and recalling of potential ovipositing sites can influence oviposition preference. Classical conditioning experiments have shown that vinegar flies can learn the association of olfactory, gustatory, or visual stimuli with either positive or negative unconditioned stimuli. However, less is known about whether similar associations are formed in an ecologically more relevant context like during oviposition. Our experiments reveal that Drosophila melanogaster females increase their preference for substrates they have already experienced. However, this change of preference requires that the flies not only smelled or touched the substrates but also oviposited on them. We furthermore show that such an experience results in long-term memory lasting for at least 4 days, i.e., a duration that so far was shown only for aversive conditioning. Our study thus reveals a different form of associative learning in D. melanogaster that might be highly relevant for settling novel ecological niches., Competing Interests: The authors declare no competing interests., (© 2024 The Authors.)

Importance: Given the high number of opioid overdose deaths in the US and the complex epidemiology of opioid use disorder (OUD), systems models can serve as a tool to identify opportunities for public health interventions., Objective: To estimate the projected 3-year association between public health interventions and opioid overdose-related outcomes among persons with OUD., Design, Setting, and Participants: This decision analytical model used a simulation model of the estimated US population aged 12 years and older with OUD that was developed and analyzed between January 2019 and December 2023. The model was parameterized and calibrated using 2019 to 2020 data and used to estimate the relative change in outcomes associated with simulated public health interventions implemented between 2021 and 2023., Main Outcomes and Measures: Projected OUD and medications for OUD (MOUD) prevalence in 2023 and number of nonfatal and fatal opioid-involved overdoses among persons with OUD between 2021 and 2023., Results: In a baseline scenario assuming parameters calibrated using 2019 to 2020 data remained constant, the model projected more than 16 million persons with OUD not receiving MOUD treatment and nearly 1.7 million persons receiving MOUD treatment in 2023. Additionally, the model projected over 5 million nonfatal and over 145 000 fatal opioid-involved overdoses among persons with OUD between 2021 and 2023. When simulating combinations of interventions that involved reducing overdose rates by 50%, the model projected decreases of up to 35.2% in nonfatal and 36.6% in fatal opioid-involved overdoses among persons with OUD. Interventions specific to persons with OUD not currently receiving MOUD treatment demonstrated the greatest reduction in numbers of nonfatal and fatal overdoses. Combinations of interventions that increased MOUD initiation and decreased OUD recurrence were projected to reduce OUD prevalence by up to 23.4%, increase MOUD prevalence by up to 137.1%, and reduce nonfatal and fatal opioid-involved overdoses among persons with OUD by 6.7% and 3.5%, respectively., Conclusions and Relevance: In this decision analytical model study of persons with OUD, findings suggested that expansion of evidence-based interventions that directly reduce the risk of overdose fatality among persons with OUD, such as through harm reduction efforts, could engender the highest reductions in fatal overdoses in the short-term. Interventions aimed at increasing MOUD initiation and retention of persons in treatment projected considerable improvement in MOUD and OUD prevalence but could require a longer time horizon for substantial reductions in opioid-involved overdoses.

Teamwork in graduate medical education (GME) is often hindered in clinical learning environments where discontinuity among residents, supervisors, and other health care professionals is typical. Teaming is a conceptual approach to teamwork in dynamic environments with constantly changing team members and goals. Teaming is built on principles of project management and team leadership, which together provide an attractive strategy for addressing teamwork challenges in GME. Indeed, teaming is now a requirement of the Accreditation Council for Graduate Medical Education Clinical Learning Environment Review program. However, many clinician-educators and leaders may be unfamiliar with teaming and how to integrate it into their GME programs. In this article, the teaming framework is described with a specific example of how it can be applied to improve hospital ward rounds, a common setting of teamwork breakdown. The goal of this article is to educate and encourage GME leaders as they learn new ways to implement teaming to improve patient care and education in their programs., Competing Interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

Suicide is a leading cause of death in the United States, particularly among adolescents. In recent years, suicidal ideation, attempts, and fatalities have increased. Systems maps can effectively represent complex issues such as suicide, thus providing decision-support tools for policymakers to identify and evaluate interventions. While network science has served to examine systems maps in fields such as obesity, there is limited research at the intersection of suicidology and network science. In this paper, we apply network science to a large causal map of adverse childhood experiences (ACEs) and suicide to address this gap. The National Center for Injury Prevention and Control (NCIPC) within the Centers for Disease Control and Prevention recently created a causal map that encapsulates ACEs and adolescent suicide in 361 concept nodes and 946 directed relationships. In this study, we examine this map and three similar models through three related questions: (Q1) how do existing network-based models of suicide differ in terms of node- and network-level characteristics? (Q2) Using the NCIPC model as a unifying framework, how do current suicide intervention strategies align with prevailing theories of suicide? (Q3) How can the use of network science on the NCIPC model guide suicide interventions?, Competing Interests: Competing interests. None.

Abstract: Opioid prescribing varies widely, and prescribed opioid dosages for an individual can fluctuate over time. Patterns in daily opioid dosage among patients prescribed long-term opioid therapy have not been previously examined. This study uses a novel application of time-series cluster analysis to characterize and visualize daily opioid dosage trajectories and associated demographic characteristics of patients newly initiated on long-term opioid therapy. We used 2018 to 2019 data from the IQVIA Longitudinal Prescription (LRx) all-payer pharmacy database, which covers 92% of retail pharmacy prescriptions dispensed in the United States. We identified a cohort of 277,967 patients newly initiated on long-term opioid therapy during 2018. Patients were stratified into 4 categories based on their mean daily dosage during a 90-day baseline period (<50, 50-89, 90-149, and ≥150 morphine milligram equivalent [MME]) and followed for a 270-day follow-up period. Time-series cluster analysis identified 2 clusters for each of the 3 baseline dosage categories <150 MME and 3 clusters for the baseline dosage category ≥150 MME. One cluster in each baseline dosage category comprised opioid dosage trajectories with decreases in dosage at the end of the follow-up period (80.7%, 98.7%, 98.7%, and 99.0%, respectively), discontinuation (58.5%, 80.0%, 79.3%, and 81.7%, respectively), and rapid tapering (50.8%, 85.8%, 87.5%, and 92.9%, respectively). These findings indicate multiple clusters of patients newly initiated on long-term opioid therapy who experience discontinuation and rapid tapering and highlight potential areas for clinician training to advance evidence-based guideline-concordant opioid prescribing, including strategies to minimize sudden dosage changes, discontinuation, or rapid tapering, and the importance of shared decision-making., (Copyright © 2023 Written work prepared by employees of the Federal Government as part of their official duties is, under the U.S. Copyright Act, a “work of the United States Government” for which copyright protection under Title 17 of the United States Code is not available. As such, copyright does not extend to the contributions of employees of the Federal Government.)

Background: Suicide is currently the second leading cause of death among adolescents ages 10-14, and third leading cause of death among adolescents ages 15-19 in the United States (U.S). Although we have numerous U.S. based surveillance systems and survey data sources, the coverage offered by these data with regard to the complexity of youth suicide had yet to be examined. The recent release of a comprehensive systems map for adolescent suicide provides an opportunity to contrast the content of surveillance systems and surveys with the mechanisms listed in the map., Objective: To inform existing data collection efforts and advance future research on the risk and protective factors relevant to adolescent suicide., Methods: We examined data from U.S. based surveillance systems and nationally-representative surveys that included (1) observations for an adolescent population and (2) questions or indicators in the data that identified suicidal ideation or suicide attempt. Using thematic analysis, we evaluated the codebooks and data dictionaries for each source to match questions or indicators to suicide-related risk and protective factors identified through a recently published suicide systems map. We used descriptive analysis to summarize where data were available or missing and categorized data gaps by social-ecological level., Results: Approximately 1-of-5 of the suicide-related risk and protective factors identified in the systems map had no supporting data, in any of the considered data sources. All sources cover less than half the factors, except the Adolescent Brain Cognitive Development Study (ABCD), which covers nearly 70% of factors., Conclusions: Examining gaps in suicide research can help focus future data collection efforts in suicide prevention. Our analysis precisely identified where data is missing and also revealed that missing data affects some aspects of suicide research (e.g., distal factors at the community and societal level) more than others (e.g., proximal factors about individual characteristics). In sum, our analysis highlights limitations in current suicide-related data availability and provides new opportunities to identify and expand current data collection efforts., (© 2023. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Purpose: Suicide is the second leading cause of death for adolescents in the United States; however, suicide is preventable and a better understanding of circumstances that contribute to death can inform prevention efforts. While the association between adolescent suicide and mental health is well established, multiple circumstances contribute to suicide risk. This study examines characteristics of adolescents who died by suicide and differences in circumstances between those with and without known mental health conditions at the time of death., Methods: Logistic regression models were used to estimate adjusted odds ratios and 95% confidence intervals of circumstances contributing to suicide between decedents with and without known mental health conditions using data from the 2013 to 2018 National Violent Death Reporting System (analyzed in 2021)., Results: Decedents with a known mental health condition were 1.2-1.8 times more likely to experience problematic alcohol misuse, substance misuse, family and other nonintimate relationship problems, and school problems; however, there were no significant differences between those with and without a known mental health condition for the preceding circumstances of arguments or conflicts, criminal or legal problems, or any crisis occurring within the two weeks prior to death., Discussion: A comprehensive suicide prevention approach can address not only mental health conditions as a risk factor but also life stressors and other crises experienced among adolescents without known mental health conditions., (Published by Elsevier Inc.)