Fuel Injector: Air swirl characterization aerothermal modeling, phase 2, volume 2

A well integrated experimental/analytical investigation was conducted to provide benchmark quality data relevant to prefilming type airblast fuel nozzle and its interaction with combustor dome air swirler. The experimental investigation included a systematic study of both single-phase flows that involved single and twin co-axial jets with and without swirl. A two-component Phase Doppler Particle Analyzer (PDPA) equipment was used to document the interaction of single and co-axial air jets with glass beads that simulate nonevaporating spray and simultaneously avoid the complexities associated with fuel atomization processes and attendant issues about the specification of relevant boundary conditions. The interaction of jets with methanol spray produced by practical airblast nozzle was also documented in the spatial domain of practical interest. Model assessment activities included the use of three turbulence models (k-epsilon, algebraic second moment (ASM) and differential second moment (DSM)) for the carrier phase, deterministic or stochastic Lagrangian treatment of the dispersed phase, and advanced numerical schemes. Although qualitatively good comparison with data was obtained for most of the cases investigated, the model deficiencies in regard to modeled dissipation rate transport equation, single length scale, pressure-strain correlation, and other critical closure issues need to be resolved before one can achieve the degree of accuracy required to analytically design combustion systems

Fuel injector: Air swirl characterization aerothermal modeling, phase 2, volume 1

A well integrated experimental/analytical investigation was conducted to provide benchmark quality relevant to a prefilming type airblast fuel nozzle and its interaction with the combustor dome air swirler. The experimental investigation included a systematic study of both single-phase flows that involved single and twin co-axial jets with and without swirl. A two-component Phase Doppler Particle Analyzer (PDPA) was used to document the interaction of single and co-axial air jets with glass beads that simulate nonevaporating spray and simultaneously avoid the complexities associated with fuel atomization processes and attendant issues about the specification of relevant boundary conditions. The interaction of jets with methanol spray produced by practical airblast nozzle was also documented in the spatial domain of practical interest. Model assessment activities included the use of three turbulence models (k-epsilon, algebraic second moment (ASM), and differential second moment (DSM)) for the carrier phase, deterministic or stochastic Lagrangian treatment of the dispersed phase, and advanced numerical schemes. Although qualitatively good comparison with data was obtained for most of the cases investigated, the model deficiencies in regard to modeled dissipation rate transport equation, single length scale, pressure-strain correlation, and other critical closure issues need to be resolved before one can achieve the degree of accuracy required to analytically design combustion systems

Homelessness predicts attrition but not alcohol abstinence in outpatients experiencing co-occurring alcohol dependence and serious mental illness.

BACKGROUND: Adults experiencing homelessness and serious mental illnesses (SMI) are at an increased risk of poor mental health and treatment outcomes compared with stably housed adults with SMI. The additional issue of alcohol misuse further complicates the difficulties of those living with homelessness and SMI. In this secondary data analysis, the authors investigated the impact of homelessness on attrition and alcohol use in a contingency management (CM) intervention that rewarded alcohol abstinence in outpatients with SMI. METHODS: The associations between housing status and attrition and alcohol abstinence during treatment, as assessed by ethyl glucuronide (EtG) urine tests, were evaluated in 79 adults diagnosed with alcohol dependence and SMI. RESULTS: Thirty-nine percent (n = 31) of participants reported being homeless at baseline. Individuals who were homeless were more likely to drop out of CM (n = 10, 62.5%) than those who were housed (n = 4, 16.7%), χ CONCLUSIONS: Individuals experiencing homelessness and co-occurring alcohol dependence and SMI receiving CM had higher rates of attrition, relative to those who were housed. Homelessness was not associated with differences in biologically assessed alcohol abstinence

Prevalence and Correlates of Cannabis Use in Outpatients with Serious Mental Illness Receiving Treatment for Alcohol Use Disorders.

Introduction: People with serious mental illness (SMI) use cannabis more than any other illicit drug. Cannabis use is associated with increased psychotic symptoms and is highly comorbid with alcohol use disorders (AUDs). Despite the national trend toward decriminalization, little is known about the prevalence, correlates, and impact of cannabis use on those with SMI receiving treatment for substance use disorders, a group at high risk for the negative effects of cannabis use. Methods: In this secondary data analysis, cannabis use prevalence, correlates, and impact on treatment outcomes were examined in 121 adults with cooccurring SMI and AUDs receiving outpatient addiction treatment in a randomized trial of contingency management (CM) for alcohol. Prevalence and frequency of cannabis use were calculated across the 7-month study period using self-report and urine tests. Cannabis users were compared with nonusers by SMI diagnosis, psychiatric symptoms, medical problems, legal problems, and HIV-risk behavior. The relationship between cannabis use and longest duration of alcohol abstinence in participants randomized to CM (n=40) was assessed. Results: Fifty-seven (47%) of participants submitted at least one cannabis-positive urine sample during the study. Out of the 2834 total samples submitted, 751 (27%) were positive for cannabis. Cannabis users were 2.2 times more likely to submit an alcohol-positive sample, and 2.5 times more likely to submit a cocaine-positive sample at baseline, relative to noncannabis users (p=0.01). Cannabis users were more likely to engage in risky sexual behavior (p=0.01) and to report being homeless (p=0.03) than nonusers. When controlling for pretreatment alcohol use, the relationship between comorbid cannabis use and alcohol abstinence during CM was not significant (p=0.77). Conclusion: Rates of comorbid cannabis use were high in this sample of adults with SMI and AUDs. Cannabis use was correlated with recent alcohol and cocaine use, risky sexual behavior, and homelessness, but not with alcohol abstinence during CM

Interaction between pre-treatment drug use and heterogeneity of psychiatric diagnosis predicts outcomes in outpatients with co-occurring disorders.

We examined whether the interaction of baseline stimulant use, assessed by urine drug tests, and type of serious mental illness (SMI) diagnosis predicted stimulant use in a trial of contingency management (CM). The interaction between baseline stimulant use and SMI diagnoses was significant in the overall sample (p=0.002) when controlling for the main effects of treatment condition, baseline stimulant use, and SMI diagnosis. Similar results were also found within the CM sample. Individuals with bipolar disorder were more or less likely, depending on their baseline stimulant-drug test results, to use stimulants during treatment compared to those with other SMI diagnoses

A Randomized Controlled Trial of Ethyl Glucuronide-Based Contingency Management for Outpatients With Co-Occurring Alcohol Use Disorders and Serious Mental Illness.

OBJECTIVE: The authors examined whether a contingency management intervention using the ethyl glucuronide (EtG) alcohol biomarker resulted in increased alcohol abstinence in outpatients with co-occurring serious mental illnesses. Secondary objectives were to determine whether contingency management was associated with changes in heavy drinking, treatment attendance, drug use, cigarette smoking, psychiatric symptoms, and HIV-risk behavior. METHOD: Seventy-nine (37% female, 44% nonwhite) outpatients with serious mental illness and alcohol dependence receiving treatment as usual completed a 4-week observation period and were randomly assigned to 12 weeks of contingency management for EtG-negative urine samples and addiction treatment attendance, or reinforcement only for study participation. Contingency management included the variable magnitude of reinforcement prize draw procedure contingent on EtG-negative samples (/mL) three times a week and weekly gift cards for outpatient treatment attendance. Urine EtG, drug test, and self-report outcomes were assessed during the 12-week intervention and 3-month follow-up periods. RESULTS: Contingency management participants were 3.1 times (95% CI=2.2-4.5) more likely to submit an EtG-negative urine test during the 12-week intervention period, attaining nearly 1.5 weeks of additional alcohol abstinence compared with controls. Contingency management participants had significantly lower mean EtG levels, reported less drinking and fewer heavy drinking episodes, and were more likely to submit stimulant-negative urine and smoking-negative breath samples, compared with controls. Differences in self-reported alcohol use were maintained at the 3-month follow-up. CONCLUSIONS: This is the first randomized trial utilizing an accurate and validated biomarker (EtG) to demonstrate the efficacy of contingency management for alcohol dependence in outpatients with serious mental illness

Provider perspectives on the impact of COVID-19 on treatment of substance use and opioid use disorders among American Indian and Alaska Native adults

IntroductionAmerican Indian/Alaska Native (AI/AN) communities are more likely to suffer negative consequences related to substance misuse. The COVID-19 pandemic exacerbated the opioid poisoning crisis, in combination with ongoing treatment barriers resulting from settler-colonialism, systemic oppression and racial discrimination. AI/AN adults are at greatest risk of COVID-19 related serious illness and death. In collaboration with an Indigenous community advisory board and Tribal leadership, this study explored AI/AN treatment provider perceptions of client-relatives’ (i.e., SUD treatment recipients) experiences during the pandemic from 2020 to 2022.MethodsProviders who underwent screening and were eligible to participate (N = 25) represented 6 programs and organizations serving rural and urban areas in Washington, Utah, and Minnesota. Participants engaged in audio-recorded 60–90 min semi-structured individual interviews conducted virtually via Zoom. The interview guide included 15 questions covering regulatory changes, guidance for telemedicine, policy and procedures, staff communication, and client-relatives’ reactions to implemented changes, service utilization, changes in treatment modality, and perceptions of impact on their roles and practice. Interview recordings were transcribed and de-identified. Members of the research team independently reviewed transcripts before reaching consensus. Coding was completed in Dedoose, followed by analyses informed by a qualitative descriptive approach.ResultsFive main domains were identified related to client-relative experiences during the COVID-19 pandemic, as observed by providers: (1) accessibility, (2) co-occurring mental health, (3) social determinants of health, (4) substance use, coping, and harm reduction strategies, and (5) community strengths. Providers reported the distinctive experiences of AI/AN communities, highlighting the impact on client-relatives, who faced challenges such as reduced income, heightened grief and loss, and elevated rates of substance use and opioid-related poisonings. Community and culturally informed programming promoting resilience and healing are outlined.ConclusionFindings underscore the impact on SUD among AI/AN communities during the COVID-19 pandemic. Identifying treatment barriers and mental health impacts on client-relatives during a global pandemic can inform ongoing and future culturally responsive SUD prevention and treatment strategies. Elevating collective voice to strengthen Indigenous informed systems of care to address the gap in culturally-and community-based services, can bolster holistic approaches and long-term service needs to promote SUD prevention efforts beyond emergency response efforts