Unraveling the Ultrafast Photochemical Dynamics of Nitrobenzene in Aqueous Solution.

Nitroaromatic compounds are major constituents of the brown carbon aerosol particles in the troposphere that absorb near-ultraviolet (UV) and visible solar radiation and have a profound effect on the Earth's climate. The primary sources of brown carbon include biomass burning, forest fires, and residential burning of biofuels, and an important secondary source is photochemistry in aqueous cloud and fog droplets. Nitrobenzene is the smallest nitroaromatic molecule and a model for the photochemical behavior of larger nitroaromatic compounds. Despite the obvious importance of its droplet photochemistry to the atmospheric environment, there have not been any detailed studies of the ultrafast photochemical dynamics of nitrobenzene in aqueous solution. Here, we combine femtosecond transient absorption spectroscopy, time-resolved infrared spectroscopy, and quantum chemistry calculations to investigate the primary steps following the near-UV (λ ≥ 340 nm) photoexcitation of aqueous nitrobenzene. To understand the role of the surrounding water molecules in the photochemical dynamics of nitrobenzene, we compare the results of these investigations with analogous measurements in solutions of methanol, acetonitrile, and cyclohexane. We find that vibrational energy transfer to the aqueous environment quenches internal excitation, and therefore, unlike the gas phase, we do not observe any evidence for formation of photoproducts on timescales up to 500 ns. We also find that hydrogen bonding between nitrobenzene and surrounding water molecules slows the S1/S0 internal conversion process.

Wastewater surveillance to infer COVID-19 transmission: A systematic review.

Successful detection of SARS-COV-2 in wastewater suggests the potential utility of wastewater-based epidemiology (WBE) for COVID-19 community surveillance. This systematic review aims to assess the performance of wastewater surveillance as early warning system of COVID-19 community transmission. A systematic search was conducted in PubMed, Medline, Embase and the WBE Consortium Registry according to PRISMA guidelines for relevant articles published until 31st July 2021. Relevant data were extracted and summarized. Quality of each paper was assessed using an assessment tool adapted from Bilotta et al.'s tool for environmental science. Of 763 studies identified, 92 studies distributed across 34 countries were shortlisted for qualitative synthesis. A total of 26,197 samples were collected between January 2020 and May 2021 from various locations serving population ranging from 321 to 11,400,000 inhabitants. Overall sample positivity was moderate at 29.2% in all examined settings with the spike (S) gene having maximum rate of positive detections and nucleocapsid (N) gene being the most targeted. Wastewater signals preceded confirmed cases by up to 63 days, with 13 studies reporting sample positivity before the first cases were detected in the community. At least 50 studies reported an association of viral load with community cases. While wastewater surveillance cannot replace large-scale diagnostic testing, it can complement clinical surveillance by providing early signs of potential transmission for more active public health responses. However, more studies using standardized and validated methods are required along with risk analysis and modelling to understand the dynamics of viral outbreaks.

Examining social supply among nonmedical prescription stimulant users in the San Francisco Bay Area.

In the US, prescription stimulants are prescribed for a variety of conditions including attention deficit hyperactivity disorder (ADHD) and narcolepsy. Over the last two decades, dramatic increases in stimulant prescriptions have led to greater availability and increased risk for diversion and nonmedical use. Our own and other investigators' findings indicate that many drug "suppliers" do not fit into the traditional image of drug "dealers." These suppliers typically do not identify themselves as "dealers," but instead understand their drug distribution as sharing with people they know. Coomber and colleagues' (2007; 2013) concept of "social supply" raises the question: When friends supply or facilitate supply of drugs to friends, is this really dealing? Further, if dealing and supplying are distinct kinds of social transactions, should different types of criminal justice approaches be applied? Social supply extends our understanding of drug dealing as a complex social activity. In this article, we examine the issue of social supply among nonmedical users of prescription stimulants. We conducted a 36-month National Institute on Drug Abuse-funded project to conduct a qualitative, mixed methods study of 150 adult nonmedical prescription stimulant users in the San Francisco Bay Area. We explore intersecting factors, including life stage and social location, that contribute to decisions to use prescription stimulants nonmedically, motivations to use, knowledge about risks and benefits of prescription stimulant use, any adverse health or social consequences experienced, availability, acquisition and diversion of prescription stimulants, and differences in attitudes and behaviours. For this analysis, we rely on participants' narratives concerning prescription stimulant acquisition practices and how they understood these interactions, purchases, and exchanges with the suppliers of prescription stimulants in their social networks. The authors argue that acknowledging the distinction between social supply and "proper" drug dealing would redress the disparity between drug sharing and profiteering particularly regarding criminal sentencing.

A safer alternative: Cannabis substitution as harm reduction.

INTRODUCTION AND AIMS: Substitution is operationalised as a conscious choice made by users to use one drug instead of, or in conjunction with another based on: perceived safety, level of addiction potential, effectiveness in relieving symptoms, access and level of acceptance. Harm reduction is a set of strategies that aim to minimise problems associated with drug use while recognising that for some users, abstinence may be neither a realistic nor a desirable goal. In this paper, we aim for deeper understandings of older adult cannabis users' beliefs and substitution practices as part of the harm reduction framework. DESIGN AND METHODS: We present selected findings from our qualitative study of Baby Boomer (born 1946-1964) marijuana users in the San Francisco Bay Area. Although the sample consisted of primary cannabis users, many had personal experience with other drugs throughout their lifetimes. Data collection consisted of an audio-recorded, semi-structured in-depth life history interview followed by a questionnaire and health survey. Qualitative interviews were analysed to discover users' harm reduction beliefs and cannabis substitution practices. RESULTS: Study participants described using cannabis as a safer alternative for alcohol, illicit drugs and pharmaceuticals based on their perceptions of less adverse side effects, low-risk for addiction and greater effectiveness at relieving symptoms, such as chronic pain. DISCUSSION AND CONCLUSIONS: Cannabis substitution can be an effective harm reduction method for those who are unable or unwilling to stop using drugs completely. More research is needed on cannabis as a safer alternative.

Responsible and controlled use: Older cannabis users and harm reduction.

BACKGROUND: Cannabis use is becoming more accepted in mainstream society. In this paper, we use Zinberg's classic theoretical framework of drug, set, and setting to elucidate how older adult cannabis users managed health, social and legal risks in a context of normalized cannabis use. METHODS: We present selected findings from our qualitative study of Baby Boomer (born 1946-1964) cannabis users in the San Francisco Bay Area. Data collection consisted of a recorded, in-depth life history interview followed by a questionnaire and health survey. Qualitative interviews were analyzed to discover the factors of cannabis harm reduction from the users' perspectives. RESULTS: Interviewees made harm reduction choices based on preferred cannabis derivatives and routes of administration, as well as why, when, where, and with whom to use. Most interviewees minimized cannabis-related harms so they could maintain social functioning in their everyday lives. Responsible and controlled use was described as moderation of quantity and frequency of cannabis used, using in appropriate settings, and respect for non-users. Users contributed to the normalization of cannabis use through normification. CONCLUSION: Participants followed rituals or cultural practices, characterized by sanctions that helped define "normal" or "acceptable" cannabis use. Users contributed to cannabis normalization through their harm reduction methods. These cultural practices may prove to be more effective than formal legal prohibitions in reducing cannabis-related harms. Findings also suggest that users with access to a regulated market (medical cannabis dispensaries) were better equipped to practice harm reduction. More research is needed on both cannabis culture and alternative routes of administration as harm reduction methods.

SOX10 expression in a gangliocytic paraganglioma--a case report.

We present a case of a 49-year-old woman who underwent a pancreaticoduodenectomy for symptomatic treatment of an obstructive periampullary duodenal mass initially found on CT imaging. Histologically, the tumor showed a triphasic pattern including small round cells, a spindle-cell component and ganglion cells of varying size. Furthermore, the tumor was surrounded by a proliferation of pancreatic ducts. These features led to the diagnosis of a gangliocytic paraganglioma arising in an ectopic pancreas. Sections of the tumor were then stained for SOX10, a neural crest transcription factor, and it was shown to be positive in the ganglion cells. The exact origin of gangliocytic paragangliomas has not yet been clearly defined. However, this finding of aberrant expression of SOX10 supports the idea of these lesions being neoplastic in nature.

Baby Boomers and Cannabis Delivery Systems.

Findings for this article are derived from our National Institute on Drug Abuse (NIDA)-funded study of older and younger Baby Boomers and marijuana use. We explore Baby Boomers' use of a variety of cannabis products and the motives behind the choices they make concerning these preparations. Cannabis concentrates and edible goods have become increasingly popular over the years. With so many new ways to consume marijuana and a growing number of medical marijuana dispensaries, more and more people are using alternative cannabis products to relieve physical ailments, to improve mental health issues, and for recreational purposes. We explore Baby Boomers' motives to use and how aging may change those motives and influence their choices in cannabis delivery systems. As they get older, Boomers' health concerns grow and many have turned to these alternative cannabis products to improve mental and physical well-being, and even to reduce the potential risks of traditional marijuana smoking.