Publications by authors named "Stephenson C"

The practicality was examined of performing a cumulative dietary exposure assessment according to the requirements of the EFSA guidance on probabilistic modelling. For this the acute and chronic cumulative exposure to triazole pesticides was estimated using national food consumption and monitoring data of eight European countries. Both the acute and chronic cumulative dietary exposures were calculated according to two model runs (optimistic and pessimistic) as recommended in the EFSA guidance.

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Natural product modification with photoredox catalysis allows for mild, chemoselective access to a wide array of related structures in complex areas of chemical space, providing the possibility for novel structural motifs as well as useful quantities of less abundant congeners. While amine additives have been used extensively as stoichiometric electron donors for photocatalysis, the controlled modification of amine substrates through single-electron oxidation is ideal for the synthesis and modification of alkaloids. Here, we report the conversion of the amine (+)-catharanthine into the natural products (-)-pseudotabersonine, (-)-pseudovincadifformine, and (+)-coronaridine utilizing visible light photoredox catalysis.

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Objective: Longitudinal trends in the dispensing of antidepressant, antipsychotic and ADHD medications from 2009-2012 were examined according to age and gender of patient and prescriber speciality. Of particular interest were changing trends in the prescription of psychotropic medications to children, adolescents and young adults.

Method: Dispensing data for government-subsidised antidepressant, antipsychotic and ADHD medications were obtained from the database maintained by the Department of Human Services.

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Catalytic radical-based domino reactions represent important advances in synthetic organic chemistry. Their development benefits synthesis by providing atom- and step-economical methods to complex molecules. Intricate combinations of radical, cationic, anionic, oxidative/reductive, and transition metal mechanistic steps result in cyclizations, additions, fragmentations, ring-expansions, and rearrangements.

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The development of a room-temperature lignin degradation strategy consisting of a chemoselective benzylic oxidation with a recyclable oxidant ([4-AcNH-TEMPO]BF4) and a catalytic reductive C-O bond cleavage utilizing the photocatalyst [Ir(ppy)2(dtbbpy)]PF6 is described. This system was tested on relevant lignin model substrates containing β-O-4 linkages to generate fragmentation products in good to excellent yields.

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The enantioselective oxidative C-H functionalization of tetrahydroisoquinoline derivatives is achieved through the merger of photoredox and asymmetric anion-binding catalysis. This combination of two distinct catalysis concepts introduces a potentially general approach to asymmetric transformations in oxidative photocatalysis.

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A tandem dienone photorearrangement-cycloaddition (DPC) reaction of novel cyclohexadienone substrates tethered with various 2π and 4π reaction partners resulted in the formation of polycyclic, bridged frameworks. In particular, use of alkynyl ether-tethered substrates led to (3 + 2) cycloaddition to afford strained alkenes which could be further elaborated by intra- and intermolecular cycloaddition chemistry to produce complex, polycyclic chemotypes.

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As a health care collaborative among Trenton's hospitals, its only Federally Qualified Health Center, its Division of Health, and more than 40 community organizations serving on the Community Advisory Board, Trenton Health Team has leveraged unprecedented data sharing and direct engagement with community residents to identify the health needs and priorities for its geography. This process has resulted in a unified Community Health Needs Assessment and Community Health Improvement Plan for the city of Trenton, allowing collaborative allocation of resources to manage and improve population health in the city.

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This commentary responds to the recent critique by Weinstock and Slatin [1] of our systematic review on the effectiveness of occupational safety and health (OSH) training conducted jointly by the Institute for Work & Health (IWH) in Canada and the National Institute for Occupational Safety and Health (NIOSH) in the United States [2, 3]. We address misunderstandings of our perspectives on training, especially empowerment training, and the evaluation of such training.

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Distorted sex ratios occur in hematologic disorders. For example, chronic lymphocytic leukemia (CLL) displays disproportionate sex ratios with a large male excess. However, the underlying genetics for these disparities are poorly understood, and gender differences for specific cytogenetic abnormalities have not been carefully investigated.

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The prevalence and phylogenetic description of fungal organisms and their role as part of the intestinal ecosystem have not yet been studied extensively in dogs. This study evaluated the fungal microbiome of 19 dogs (12 healthy dogs and 7 dogs with acute diarrhea) using fungal tag-encoded FLX-Titanium amplicon pyrosequencing. Five distinct fungal phyla were identified, with Ascomycota (medians: 97.

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Aims: Old age and diabetes are risk factors that often coexist increasing the vulnerability of the heart to the lethal effects of ischaemia-reperfusion injury (IRI). However, to our knowledge, no investigations have examined IRI and cardioprotective signalling in animal models bearing these co-morbidities concomitantly. The ability of the heart to recover following IRI is greatly dependent on its innate cardioprotective potential, in which a central role is played by Akt.

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Purpose: This phase I clinical trial evaluated the safety, tolerability, and pharmacokinetics of high-dose intravenous (i.v.) ascorbic acid as a monotherapy in patients with advanced solid tumors refractory to standard therapy.

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We report a patient with a rare primary signet-ring cell carcinoma of the transverse colon with secondary leptomeningeal carcinomatosis. The only presenting and persistent symptom was worsening headache for 6 weeks until death. There were no other neurological, constitutional, or gastrointestinal symptoms.

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Unlabelled: WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Shockwave lithotripsy (SWL) can be used to treat stones at any position within the ureter, as long as the stone is radio-opaque and there is a path for the shockwave to reach the stone. However the results of SWL to distal ureteric calculi, with the patient in a prone position, were inferior to those of treating stones within the upper ureter. The transguteal approach allows the lithotripsy shockwave to reach the lower ureter via the greater selatle foramen.

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Acute liver failure (ALF) during pregnancy is very uncommon. Pregnancy-specific liver conditions like hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome and acute fatty liver of pregnancy can cause ALF at term or postpartum, but, typically occur during the third trimester. Most of these patients recover spontaneously after delivery, but, on occasion, they require liver transplantation in the postpartum period.

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Objective: This study examined longitudinal trends in the dispensing of psychotropic medications in Australia from January 2000 to December 2011.

Method: Dispensing data for the major classes of psychotropic medications (antidepressants, anxiolytics, sedatives, antipsychotics, mood stabilisers and attention-deficit hyperactivity disorder (ADHD) medications) were obtained from the Drug Utilisation Sub-Committee of the Australian Department of Health and Ageing. Results were expressed in terms of defined daily doses/1000 population/day (DDDs/1000/day).

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Herein we report a one-pot deoxygenation protocol for primary and secondary alcohols developed via the combination of the Garegg-Samuelsson reaction, visible light-photoredox catalysis, and flow chemistry. This procedure is characterized by mild reaction conditions, easy-to-handle reactants and reagents, excellent functional group tolerance, and good yields.

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A mild and practical synthesis of spirooxindole [1,3]oxazino derivatives from N-substituted isatins and 1,3-dicarbonyl compounds with pyridine derivatives is reported. The reactions provided good to excellent yields. Further exploration of the molecular diversity of these compounds is demonstrated through Diels-Alder reactions.

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The discovery of genomic abnormalities present in monoclonal plasma cells has diagnostic, prognostic, and disease-monitoring implications in plasma cell neoplasms (PCNs). However, technical and disease-related limitations hamper the detection of these abnormalities using cytogenetic analysis or fluorescence in situ hybridization (FISH). In this study, 28 bone marrow specimens with known PCNs were examined for the presence of genomic abnormalities using microarray analysis after plasma cell enrichment.

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Radical reactions are a powerful class of chemical transformations. However, the formation of radical species to initiate these reactions has often required the use of stoichiometric amounts of toxic reagents, such as tributyltin hydride. Recently, the use of visible-light-mediated photoredox catalysis to generate radical species has become popular, but the scope of these radical precursors has been limited.

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Previous research on the theory of planned behavior (TPB) is characterized by cross-sectional tests of the model's proposed causal relationships. In the absence of effective experimental techniques for changing the TPB's cognitive antecedents, the present research aimed to provide a stronger non-experimental test of the model, using causal analyses of two-wave panel data. Two studies of driver behavior were conducted in which naturally occurring within-participant changes in TPB constructs were measured over time, and used to predict corresponding within-participant changes in both intentions and behavior.

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This mini-review highlights the Stephenson group's contribution to the field of photoredox catalysis with emphasis on carbon-carbon bond formation. The realization of photoredox mediated reductive dehalogenation initiated investigations toward both intra- and intermolecular coupling reactions. These reactions commenced via visible light-mediated reduction of activated halogens to give carbon-centered radicals that were subsequently involved in carbon-carbon bond forming transformations.

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