Crack Cocaine Research Articles

Pressure-dependent joint elastic–electrical properties in brine-saturated artificial sandstones with aligned penny-shaped cracks—Part I: Experimental results

SUMMARY Elastic and electrical properties can be jointly interpreted for better characterizations of rocks with cracks that are common in geological rocks. However, the cross-property relationship between the elastic and electrical properties of cracked rocks, which forms the key to the successful joint elastic–electrical interpretation, remains poorly understood. We investigate the pressure effects on the joint elastic–electrical properties in brine-saturated artificial sandstones with aligned non-interacting penny-shaped cracks that are far from percolation. We measured and compared the anisotropic electrical conductivity and ultrasonic velocity in the artificial sandstones with and without aligned cracks under applied effective stress from 5 to 50 MPa. We showed that the existence of aligned cracks significantly enhanced the elastic and electrical anisotropies of the rocks, and the difference in the elastic and electrical anisotropies between the cracked and intact samples reduced as the effective stress increased. We also showed that the pressure-dependent electrical conductivity and ultrasonic velocity exhibited strong linear correlations in both the intact and cracked samples cored in different directions, and a difference existed in the slopes between the samples with and without aligned cracks. The distinct contributions of the pressure-induced deformation of cracks to the anisotropic elastic and electrical properties, as well as their different sensitivity to the cracks, were found to plausibly explain the observed experimental results. Theoretical modelling for quantitative interpretation of the experimental data is presented in a companion paper.

Non-fatal stimulant overdose among homeless and unstably housed women in San Francisco, California

BackgroundUS rates of overdose deaths involving stimulants (e.g., cocaine or methamphetamine) have increased, but little is known about non-fatal stimulant overdoses, particularly among vulnerable populations. We characterized rates of non-fatal stimulant overdose identified outside of health care settings among women at high risk. MethodsHomeless and unstably housed women in San Francisco, California using stimulants were administered questionnaires on drug use and outcomes (stimulant overdose, health care utilization) monthly for six months. Based on pilot interviews, stimulant overdose during follow-up was defined as acute toxicity from stimulant use (“over-amping”) resulting in “feeling sick, really scared, or like one’s life may be in danger”. Poisson regression estimated unadjusted incidence rate ratio (IRR) comparing participant characteristics. ResultsWe included 160 women (41% Black, 26% White, 15% Latina, median age 54 years) using crack cocaine (81%), methamphetamine (48%), and powdered cocaine (36%). Participants reported 67 non-fatal stimulant overdoses over 685 person-months of observation, a rate of 117.4 per 100 person-years (95% CI 85.8–160.5). Rates were higher among participants who were Latina vs. White (IRR 4.18 [1.60–10.94]), used methamphetamine (IRR 1.80 [0.96–3.38]), or used any stimulant daily/almost daily (IRR 2.63 [1.41–4.91]). Among women reporting stimulant overdose, 4% received emergency and 3% inpatient care for overdose of any drug. ConclusionsWomen in this setting, particularly those who used stimulants frequently or used methamphetamine, experienced high non-fatal stimulant overdose and rarely received health care for these events. Efforts should be made to increase awareness and reduce harms of stimulant toxicity in vulnerable populations.

Application of Configuration Force to Dynamic Crack of Shale under Hydration

The natural microdefects of shale and the expansion of microcracks under hydration and overlying rock loadings are important for the wellbore stability. According to the conservation of energy, the force of the microdefects and microcracks under finite deformation is studied by the method of configuration force through the migrating control volume in the spatial observer. Under the hydration stress and rock pressure, the equation of hydration stress and its work in reference configuration has been obtained, and the equations of configuration forces and configuration moment have been established as a consequence of invariance under changes. The relationship between the configuration and deformation forces is determined by the second law. The energy dissipation equation of the crack tip has been deduced, which shows that the projection of the concentrated internal configuration body force at the crack tip in the opposite direction of the crack is equal to the energy dissipation of the crack tip per unit length. The inertial and internal parts of the concentrated configuration body force at the crack tip have been derived; it is indicated that the internal configuration force plays a leading role in the irreversible fracture process. Moreover, the energy release rate of shale under hydration is proved to depend on constitutive responses and hydration stress. In the theoretical system of configuration force, the migrating control volume at the crack tip contains inclusions, microcracks, microvoids, and heterogeneity of the rock itself. We use the configuration force theory to solve the problem of rock crack propagation and rock fracture. The factors considered are more comprehensive, which can better reflect the actual situation and provide a theoretical basis for the study of wellbore stability.

Associations amongst form of cocaine used (powder vs crack vs both) and HIV-related outcomes

IntroductionCocaine (including powder and crack) use is common among people with HIV (PWH). We identified socio-demographic and behavioral factors associated with cocaine use (overall and various forms) among PWH; we also examined differences in HIV treatment outcomes across cocaine exposure groups. MethodsThe study sample (N = 1166) was derived from two cohorts of PWH in Florida between 2014 and 2020. Baseline data were linked to the Enhanced HIV/AIDS Reporting System (eHARS) which tracks HIV viral load. Socio-demographics and polysubstance use were compared by cocaine use and the three cocaine use groups (powder only n = 101, crack only n = 91, or both n = 65). The association between the three cocaine use groups, ART adherence, and HIV viral suppression (<200 copies/mL) in the following year was assessed by multivariate logistic regression. ResultsPeople who used cocaine had lower HIV treatment adherence and viral suppression than those who did not use. People who used powder cocaine only were more likely to be younger, Hispanic/Latinx, and employed than those who used crack only or both. Compared to people who used both powder and crack cocaine, those who used one form of cocaine had 3 + odds of having durable viral suppression in the following year. ConclusionThe dual use of both powder and crack cocaine was associated with significantly worse HIV outcomes compared to use of only one form of cocaine. Screening for powder and crack cocaine use and timely intervention are needed to improve HIV treatment outcomes among this high-risk population.

Association between alcohol and crack: Prevalence, effects, associated factors and experiences of combined use.

ObjectiveTo estimate the prevalence and factors associated with the effect of alcohol on crack cocaine use and to analyze experiences related to combined use. Materials and methods: sequential mixed methods (qualitative and quantitative) research, carried out between August 2014 and August 2015 with people who use crack. In the quantitative approach, a cross-sectional study was conducted with 1,062 participants. Factors associated with “alcohol use with the effect of increasing the effect of crack/crack craving” were estimated by multiple regression. In the qualitative approach, 39 interviews were conducted using Bardin’s content analysis technique.Results871 (82.0%) participants reported consuming alcohol, among them, 668 (76.7%) used alcohol combined with crack: 219 (32.8%) reported feeling an effect of reduction in paranoia and/or crack craving and 384 (57.5%) reported feeling an increase in the effect of crack and in the craving to consume the drug. This relationship was also observed in the narratives of the people who use crack, with the possibility of a cyclic effect of consumption of the two substances. Those who related alcohol use to the effect of increasing crack craving (384) were more likely to use alcohol before crack (OR: 1.81; 95%CI: 1.13–2.89); to consume more than 20 stones daily (OR: 1.48; 95%CI: 1.01–2.16); to remain in abstinence from crack for less than one month (OR: 3.20; 95%CI: 1.91–5.35); to use dependence treatment services (OR: 1.85; 95%CI: 1.26–2.71); and to commit physical violence (OR:1.67; 95%CI:1.08–2.56).ConclusionThe findings of this study indicate that the modulation of the effect of alcohol use on crack cocaine depends on the moment when the drugs are consumed, and the use of alcohol before crack consumption is associated with characteristics that suggest a greater vulnerability to patterns of harmful crack use. Even though combined use is referred to as a way of reducing the negative effects of crack, the damage of this association may be greater than its possible benefits.

Prevalence of crack cocaine use and its associated factors in patients treated in a specialized outpatient service

Abstract Background Despite the advance in studies addressing the use of crack cocaine, knowledge about the characteristics of users that seek treatment in the different modalities of care for substance use disorders is important to plan the operationalization of these services. Objective To analyze the prevalence and factors associated with the use of crack cocaine in outpatients. Method Cross-sectional study consisting in the analysis of the medical records of outpatients of a chemical dependency clinic located in the south of Brazil from 1999 to 2015. The Fisher’s exact test and the Poisson regression model were used to analyze the data. Results Medical records from 1,253 patients were analyzed, and 1,196 (95.5%) of them contained information on the use of crack cocaine. Use of this substance was reported by 47% (95% CI [44, 50]) of the outpatients. The risk group was composed of adults aged 20-39 years, with no income, who had three or more children, did not consume alcohol or marijuana, had continuous family assistance, spontaneously looked for the service, and had already been hospitalized or assisted at a therapeutic community or psychosocial center. Conclusion There is great demand for the outpatient care of crack cocaine users. It is crucial that the risk factors guide treatment planning.

27736 Painful retiform purpura with cutaneous necrosis

A 46-year-old Caucasian male with a past medical history significant for hepatitis C virus (HCV) infection, metastatic melanoma, and years of crack cocaine use presented to the emergency department with a one-week history of painful lesions involving the nose, limbs, and mouth. Skin exam showed painful purpura of the ears and right nasal ala, retiform purpura with necrosis of all four extremities, and an ulcer of the left buccal mucosa. His initial laboratory values were significant for microcytic anemia, decreased complement levels, and a positive drug screen for cocaine.

Criminalized or Medicalized? Examining the Role of Race in Responses to Drug Use

AbstractDrug policy has shifted from intense criminalization toward reforms that prioritize decarceration and treatment. Despite this shift, little is known about whether support for recent treatment-oriented drug policy is equitable by users’ race and the drug type. Using the opiate and crack cocaine crises as cases, we analyze 400 articles from the New York Times and Washington Post to assess the degree to which the two crises were racialized, criminalized, and medicalized. We find that media coverage medicalized and humanized White people who use opiates, while coverage of crack cocaine focused on criminalization, vilifying Black people who use drugs. We then conduct two vignette experiments (N=308; N=630) to examine whether these racialized frames shape public support for treatment or criminalization. We find the public more likely to support criminalization for Black people, while supporting drug treatment for White people. Respondents are more likely to support drug treatment for heroin use than for crack cocaine. Our findings suggest that support for medicalized approaches to drug use is more likely to occur for White people and drugs linked to White people, while Black people and drugs associated with Black people continue to be perceived as largely amenable to punitive options.

ASSESSMENT OF FRACTAL DIMENSION AND PANORAMIC RADIOMORPHOMETRIC INDICES IN CRACK–COCAINE-ADDICTED MEN: A CROSS-SECTIONAL STUDY

The impact of crack–cocaine dependence on the quality and microarchitecture of the mandibular bone tissue requires further investigation. This cross-sectional study evaluated the fractal dimension and panoramic radiomorphometric indices in crack–cocaine-addicted men. Panoramic radiographs were obtained from 24 addicted and 24 nonaddicted men (control individuals) between the ages of 18 years and 60 years. The fractal dimensions of four different regions, along with the cortical mandibular, mental, and panoramic mandibular indices, were evaluated bilaterally. Significance level of 5% ([Formula: see text]) was adopted in the statistical analysis. Mean fractal dimension value of all the four different regions of the jaw in the addict group ([Formula: see text]) was lower than that of the nonaddict group ([Formula: see text]; [Formula: see text]). Furthermore, the inter-group panoramic radiomorphometric indices were not significantly different ([Formula: see text]). Mean fractal dimension value was associated with the duration of addiction ([Formula: see text]; [Formula: see text]), contrary to the indices ([Formula: see text]). Crack–cocaine addiction and longer duration of addiction were associated with lower fractal dimension values in the mandibular bone. Therefore, patients and dentists should be aware of this condition while planning periodontal, implant, and orthodontic therapies. Furthermore, crack–cocaine patients should be referred to a specialist for the evaluation of osteoporosis and osteopenia.

Association between crack cocaine use and dental caries experience: a cross-sectional study in southern Brazil.

The aim of the present study was to compare the prevalence of dental caries between crack cocaine users and a control group. The study included 106 participants in each group matched for age, sex, and exposure to tobacco. Crack cocaine users were selected from institutions for the treatment of chemical dependency, and the control group was recruited from a public school and among patients who sought dental care. A calibrated examiner determined dental caries experience [Decayed, Missing and Filled Teeth (DMFT) index]. The severity of tooth decay was determined using the Significant Caries Index (SiC). The prevalence of dental caries (DMFT ≥ 1) was 96.2 and 81.1% among the crack cocaine users and nonusers, respectively. Crack users had higher mean DMFT values (7.16 versus 4.92) for the decayed and missing components as well as a higher percentage of individuals with highly severe caries compared to nonusers. After the adjustments in the multivariate model, the prevalence of caries was 18% higher among the crack users (prevalence ratio: 1.18; 95% confidence interval: 1.08-1.30). Age, family income, crack cocaine use, and dental calculus were associated with the occurrence of dental caries. In conclusion, the prevalence of caries was higher among the crack users compared with the control group and remained associated with dental caries in the multivariate analysis.

The daily life of the family living with a crack user

Background and objectives: Drug use is considered a public health problem due to the physical, biological, psychological and social repercussions caused by this phenomenon in the lives of users and society in general. The aim of this study was to describe the daily life of the family living with a crack user. Methods: This is an exploratory-descriptive qualitative study. Data were collected through a focus group with ten family members of crack addicts admitted to a drug detox treatment unit in a hospital in Rio Grande do Sul. Data were analyzed according to content analysis. Results: Based on the analysis of results, two categories emerged, namely “Feelings of family members” and “Living with concerns”. Conclusion: Crack addiction weakens family relationships and disrupts the family and social life.

Impacts of Abusing Drugs on Our Society

Alcohol, heroin, inhalants and similar are considered as drug of abuse in our society. These can ruin the lives of everyone. Infact these are slow poisons. Mostly teen agers are big victims of these drugs. They may be more likely to engage in harmful behavior. Alcohol, cigarettes, and crack cocaine are the most often consumed drugs by young people. Our objectives are to identify the effects of abusing drugs in our society and play a role to stop it. The study was done in the Faisalabad division by the interviews of people who were drug addicts through the questionnaire. This survey research was completed in March 2020 to June 2020. We interviewed about 450 drug addicts and we have found about six abusing drugs among those. The drugs were alcohol, heroin, marijuana, allergic injection, inhalant and opium and the percentage of addicts were 24, 30, 15, 14, 10 and 07 respectively. We also found 9% females and 91% males were involve and 25% were teen ager, 60% were between 20 to 40 years and 15% were above 40 years. It is concluded that authorities should play their role to stop this sin and it should be established a number of centers for treatment of the drug addicts.

Squirt flow in partially saturated cracks: a simple analytical model

SUMMARY Obtaining the seismic response of rocks containing cracks whose scales are much smaller than the prevailing wavelengths is a classic and important problem in rock physics. Seminal analytical models yield the seismic signatures of cracked rocks saturated with a single fluid phase. However, in a wide variety of practically relevant scenarios, cracks may be partially saturated with multiple immiscible fluids of contrasting compressibilities, such as gas and water. When a passing seismic wave deforms the medium, fluid pressure gradients arise within such partially saturated cracks, which, in turn, tend to relax through a process commonly known as squirt flow. The corresponding viscous dissipation may greatly affect the seismic amplitudes and velocities, as well as the anisotropic behaviour of the medium. To date, extensions of classical analytical models to include squirt flow occurring within isolated partially saturated cracks remain limited either in the saturation or in the frequency range. In this work, we present a simple analytical model to compute the seismic response of rocks containing partially saturated aligned cracks accounting for squirt flow effects. First, we solve the linearized Navier–Stokes equations within a partially saturated penny-shaped crack subjected to an oscillatory strain. Then, we obtain a closed analytical expression for a complex-valued frequency-dependent effective fluid bulk modulus which accounts for the stiffness variations of each crack due to squirt flow. Using classic effective medium models, together with such an effective saturating fluid, we retrieve the effective compliance matrix of the probed partially saturated cracked rock. The proposed analytical solution is validated by comparison with corresponding 3-D numerical simulations and existing analytical models.

Porous and cracked rocks elasticity: Macroscopic poroelasticity and effective media theory

Macroscopic poroelasticity and effective medium theory are two independent approaches which can be used to analyze the role of pores, cracks, and fluid on elastic properties. Macroscopic poroelasticity belongs to the macroscopic framework of thermodynamics whereas effective medium theory expresses the medium properties in terms of microstructural characteristics (pore and crack shape, etc.) and component properties (fluid properties, solid grain properties, etc.). In this paper, we review the fundamental assumptions and results of both approaches, and show that they are complementary but do not apply over the same range of conditions. A compilation of data is reported, in various dry and saturated rocks, to show the validity of the Gassmann equation and the dispersion between unrelaxed modulus –where effective medium model applies- and relaxed modulus –where poroelasticity applies.

Parrot Beak Nail: Case Report and Review of Parrot Beak Nail Dystrophy

Parrot beak nail dystrophy is an excessive forward curvature of the nail plate that can affect both fingernails and toenails. Few cases have been reported since its original description in 1971; however, the incidence is estimated to be 2.5% in healthy individuals. Although the pathogenesis has not yet been established, parrot beak nail has been associated with chronic crack cocaine use, congenital bone or soft tissue abnormalities, other nail dystrophies, peripheral neuropathy, systemic sclerosis, and trauma to the nail. We describe an 86-year-old man with dementia and neuropathy who presented with an unperceived parrot beak nail of his left fourth toenail and concurrent onycholysis of his left great toenail. He had stopped visits with his podiatrist for nail care, which fostered the growth of these nail dystrophies. Our patient’s parrot beak nail was successfully treated with nail clipping and regular nail maintenance to prevent its recurrence. The associated conditions, etiologies, and treatment of parrot beak nails are discussed.

Histopathological and inflammatory response in multiple organs of rats exposed to crack

ABSTRACT The aim of this study was to investigate histopathological and inflammatory response in liver and kidney of rats after crack exposure. For this purpose, a total of 32 male Wistar rats were distributed into four groups: (G1) and (G2): received 18 mg/kg of body weight (b.w) of crack cocaine, but Group G2 remained 72 h without exposure after the experimental period (5 days). Experimental group 3 (G3): received 36 mg/kg of body weight (b.w) of crack cocaine. Control Group (CTRL): received only the vehicle (DMSO) administered by intraperitoneal (i.p) route for 5 days. The results showed that crack cocaine induced histopathological changes in liver and kidney. Immunohistochemistry data revealed that G2 group showed a higher immunoexpression of Ki-67 in hepatic and renal tissues. Regarding inflammation, the results showed that all groups exposed to crack cocaine decreased the expression of TNF-α, IL-6, and IL-10 in liver and kidney. In summary, our results showed that the subacute doses of crack cocaine used in this study had cytotoxic, and immunosuppressive effects in liver and kidney of rats, especially at 36 mg/kg dose. Since cellular death and inflammation participates in the multi-step process of chemical carcinogenesis, these data offer new insights into potential ways to understand the pathobiological mechanisms induced by crack cocaine in several tissues and organs.

White House: Time to equalize cocaine‐crack sentencing

Back in 2006, a study published in the International Journal of Drug Policy found that most whites who support prison for cocaine possession blame the person who uses drugs, think that Blacks are more likely than whites to use cocaine and deny that racism is a problem or that it even exists (see “Study examines attitudes toward prison for first‐time cocaine offenders,” ADAW, June 12, 2006). At this time, sentencing disparities for crack cocaine and cocaine powder had been going on since the 1980s. The study, funded by the Robert Wood Johnson Foundation, could have been written today, but if President Joe Biden and his Office of National Drug Control Policy (ONDCP) have anything to say about it, that sentencing disparity is going to end.

Crack cocaine use among aging Mexican American men with heroin use histories: motivations and polydrug use patterns

Background Knowledge about the motivations for crack cocaine use and the long-term effects among people who inject heroin is limited. This study aims to understand motivations associated with this co-use drug pattern among aging men entrenched in established intergenerational heroin subcultures. Methods: A sample of 60 men with diverse injecting heroin use histories was recruited from low-income Mexican American urban communities for semi-structured ethnographic interviews using respondent-driven sampling. Qualitative analysis was then employed to provide an in-depth understanding of patterns and motivations of polydrug use among this older population. Results: The men discussed motivations including tolerance, curiosity and experimentation, a paradox of affordability, alternatives to the health hassles and stigma, and the cross-fertilization of drug markets. Concurrent and switching use patterns were primarily reported among those seeking a new or different high, while replacement patterns were reported by men in methadone treatment or by those who had tired of injection. Discussion: Findings translate to the on-going opioid crisis and the emerging trend in polysubstance use involving crack cocaine, methamphetamine and other psychostimulants among people who use heroin. More research is needed to investigate the full range of social and health consequences associated with these co-use patterns. Targeted and tailored prevention and treatment services are essential to improve outcomes among aging Mexican American men who use heroin and other persons with similar polydrug use patterns.

Social support networks of users of crack cocaine and the role of a Brazilian health program for people living on the street: A qualitative study

This cross-sectional qualitative study analyzed characteristics of social support for users of crack cocaine and the role of “Consultório na Rua” (CR), or “Office in the Street,” a Brazilian program for people living on the street. Data were collected using 1) ethnographic field observations during the delivery of services from this program, 2) in-depth interviews with 17 users of crack cocaine, and 3) a focus group with professionals from CR. To analyze data, we used content analysis and analytical categories based on Social Network Analysis (SNA) theoretical statements. Results showed that family, peers, community members, and professionals from CR were the main social support providers. Participants mentioned receiving material, informational, and emotional support from CR members. It was observed that CR had a welcoming and inclusive approach, but CR team members identified challenges related to stigma directed toward people who use substances and live on the street. CR assumed a central role in the health and social assistance of users of crack cocaine living on the street, providing an important link to healthcare and social services. However, initiatives related to motivation to receive mental health services, treatment, or social reintegration were not observed in conjunction with this program.

Estimation of directional crack density and fluid properties from well logs in vertical wells

The study of elastic properties of fractured/cracked rocks has been an important subject of interest in seismology and geophysical exploration. Downhole logging provides a direct measurement of fractured rock properties in terms of elastic wave velocities and anisotropy. Most existing studies only provide qualitative descriptions of fracture properties as evidenced from the acquired measurements. To better use downhole measurements, we have derived a comprehensive theoretical analysis and developed an inversion technique to characterize fracture properties. Theoretical results for cracked rocks show that crack density, crack alignment direction, and crack filling materials are the three main fracture parameters that strongly affect the elastic wave properties of fractured rocks. Furthermore, a detailed analysis of the crack effects on elastic properties shows that the measured elastic moduli can be used to evaluate the crack parameters of cracked rocks. We assume that cracks with any orientational distribution can be divided into two parts: horizontal and vertical. Based on the theoretical analysis, we develop an inversion method to estimate fracture parameters from well logs acquired in a vertical borehole. We assume a rock-physics model for rocks that adds effective horizontal and vertical cracks that are filled with liquid in an isotropic background, the elastic and fluid properties of which are inverted from the measured logs. The inversion method enables the quantification of the directional crack density and crack-filling material when applied to field logging measurements acquired in fractured formations. Theoretically predicted fracture properties are validated with formation microresistivity scan logging data and are consistent with the interpretation results.