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International audience; Abstract Despite the key role of the Arctic in the global Earth system, year-round in-situ atmospheric composition observations within the Arctic are sparse and mostly rely on measurements at ground-based coastal stations. Measurements of a suite of in-situ trace gases were performed in the central Arctic during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition. These observations give a comprehensive picture of year-round near-surface atmospheric abundances of key greenhouse and trace gases, i.e., carbon dioxide, methane, nitrous oxide, ozone, carbon monoxide, dimethylsulfide, sulfur dioxide, elemental mercury, and selected volatile organic compounds (VOCs). Redundancy in certain measurements supported continuity and permitted cross-evaluation and validation of the data. This paper gives an overview of the trace gas measurements conducted during MOSAiC and highlights the high quality of the monitoring activities. In addition, in the case of redundant measurements, merged datasets are provided and recommended for further use by the scientific community.

The increase in levels of mercury in the environment is a truly global concern, recognised in the preparation and signing of the Minamata Convention on Mercury by 128 countries in 2010, and its enacting into force in 2017. The global nature of the problem lies in the persistence of mercury in the environment, leading to distribution of this neurotoxin to regions far-removed from sources, be they natural or anthropogenic. Understanding of the biogeochemical cycling of mercury is critical in order to estimate the legacy of previously emitted mercury, and to assess the effectiveness of control measures designed to decrease releases to the environment. This biogeochemical cycling is a complex system of processes, as the unique physicochemical properties of mercury allow for constant exchange between atmospheric, aquatic, terrestrial and biological reservoirs. Variation to rates, magnitudes and directions of this exchange take place across temporal and spatial scales, necessitating an increase in the number of biogeochemical cycling investigations implemented across the globe. Investigations such as these are limited in the context of the Australian environment. Modelling efforts have taken place to quantify and characterise biogeochemical cycling in Australia, though these are based on field and laboratory parameterisations undertaken elsewhere around the globe, and may not be suitably applicable to Australia's unique environs. Large, sparsely-populated and girt by sea, Australia is relatively unimpacted by local anthropogenic emissions of mercury. Instead, sources of mercury to this island continent are thought to be dominated by long-range transport, particularly through the atmosphere. Despite this, no long-term monitoring datasets of atmospheric mercury exist over Australia. This thesis presents the first multi-year investigations into atmospheric mercury levels in Australia. These investigations take place at two locations spanning the breadth of Australia's climate zones - one in tropical Northern Territory and the other in temperate Tasmania. Comparison between the two suggests that atmospheric mercury concentrations are largely congruous, despite very different source types and source regions. Further comparison with similar datasets taken elsewhere suggests this is broadly the case for the Southern Hemisphere in general, and that the concentration of atmospheric mercury is lower than previously believed. In this context, this thesis also investigates two important aspects regarding the natural biogeochemical cycling of mercury - delivery of atmospheric mercury to vegetation communities, and its release from these communities as a result of biomass burning. In both cases it is found that exchange of mercury is lower than previously believed, and that storage of mercury in Australian vegetation is up to 90 % lower than parameters currently used in biogeochemical modelling efforts. Depletion of ambient elemental mercury as a result of surface deposition under stable nocturnal boundary layers was observed at two locations, and throughout the year at one of these. Re-emission in the following morning at both sites provides further evidence for the prompt recycling process of atmospheric mercury transport. These investigations represent a first step in developing parameterisations unique to the Australian continent, and will serve as part of the wider global effort to monitor and mitigate the impacts of mercury on both humans and the natural environment.

The genetic basis of chronic lymphocytic leukemia (CLL) has not been fully elucidated to date. Although it is the most common haematological malignancy in Caucasians, it is uncommon among Asians. A recent genome-wide scan of CLL in Caucasians, which was carried out in the UK, identified six variants showing strong association. We attempted to replicate these findings in 71 patients with CLL and 1273 controls in Hong Kong Chinese. Three of the six variants were significantly associated with CLL. The rs872071 variant (Odds Ratio (95% Confidence Interval) = 1.78 (1.25-2.53), P = 0.0013) in the IRF4 gene region showed the strongest association, similar to that reported in the UK study. Polymorphisms in SP140 and ACOXL were also associated with risk of CLL. Further, the mean allele frequencies of the six variants were moderately (59%) to extremely (0.5%) lower in the Chinese population compared with Caucasians. These results suggest that variants in three loci may contribute to risk of CLL among Chinese.

Those who knew Dr. Purpura when he was teaching know exactly what I am talking about. We met, Judi (Howard Dean's wife) and I, in his class. The reason I got 35 (the passing grade being 34) was because we were doing the New York Times crossword puzzles at the back of the class. We had been doing the puzzles in some of the classes because the classes were boring. Dr. Purpura's class was never boring. In fact, doing the puzzles was actually self-defense, in that the class was terrifying. So much information was coming so fast that we with- drew, and tried to read the syllabus later. Judi obviously retained things a lot better than I did.

Lung cancer rates in Xuanwei County have been among the highest in China for both males and females and have been causally associated with exposure to indoor smoky (bituminous) coal emissions that contain very high levels of polycyclic aromatic hydrocarbons. There are numerous coal mines across the County. Although lung cancer risk is strongly associated with the use of smoky coal as a whole, variation in risk by smoky coal subtype has not been characterized as yet. We conducted a population-based case-control study of 498 lung cancer cases and 498 controls, individually matched to case subjects on age (+/-2 years) and sex to examine risk by coal subtype. Odds ratios (ORs) and 95% confidence intervals (CIs) for coal subtype were calculated by conditional logistic regression, adjusting for potential confounders. Overall, smoky coal use was positively and statistically significantly associated with lung cancer risk, when compared with the use of smokeless coal or wood (OR = 7.7, 95% CI = 4.5-13.3). Furthermore, there was a marked heterogeneity in risk estimates for specific subtypes of smoky coal (test for heterogeneity: p = 5.17 x 10(-10)). Estimates were highest for coal of the Laibin (OR = 24.8, 95% CI = 12.4-49.6) and Longtan (OR = 11.6, 95% CI = 5.0-27.2) coal types and lower for coal from other subtypes. These findings strongly suggest that in Xuanwei and elsewhere, the carcinogenic potential of coal combustion products can exhibit substantial local variation by specific coal source.

Previous studies indicate that the relationship between empirically derived particle counts, particle mass determinations, and particle size-related silica content are not constant within mines or across mine work tasks. To better understand the variability of particle size distributions and variations in silica content by particle size in a granite quarry, exposure surveys were conducted with side-by-side arrays of four closed face cassettes, four cyclones, four personal environmental monitors, and a real-time particle counter. In general, the proportion of silica increased as collected particulate size increased, but samples varied in an inconstant way. Significant differences in particle size distributions were seen depending on the extent of ventilation and the nature and activity of work performed. Such variability raises concerns about the adequacy of silica exposure assessments based on only limited numbers of samples or short-term samples.

Globally, about 53% of lung cancer cases in women and 15% of lung cancer cases in men are not attributable to active tobacco use, making lung cancer in never smokers the seventh leading cause of cancer death. Experimental and epidemiological evidence suggest that lung cancer in never smokers has unique risk factors, clinical features, and histological distributions as compared to those lung cancer cases attributed to tobacco smoking. In general, lung cancer in never smokers presents predominately as adenocarcinoma and in females. The lung cancer rate among females in Xuanwei, China is among the highest in the world for nonsmoking females, and has been attributed to indoor air pollution from domestic fuel combustion, particularly from bituminous coal. To further explore the clinical and histological aspects of lung cancer in Xuanwei, we collected formalin-fixed paraffin embedded (FFPE) tissue samples from a series of 76 female lung cancer cases. The mean age of the patients was 47.7 years old (±9.2 years). Expert consensus review found 54 (71%) of the female lung cancer cases were adenocarcinomas (ADCs), 11 (14.5%) were squamous cell carcinomas (SCCs), 1 (1.3%) was an adenosquamous carcinoma (ADSC), 8 (10.5%) were large cell carcinomas, and 2 (2.7%) were other subtypes. We then used two multiplexed assays to detect in DNA from FFPE tissue more than 40 recurrent mutations in nine genes relevant to existing and emerging targeted lung cancer therapies among subjects who were confirmed never smoking female lung cancer cases (32 ADCs, 7 SCCs, 1 ADSC). These assays include amplification of DNA through Applied Biosystem's SNaPshot technology to detect 38 different recurrent somatic point mutations in 8 driver genes (EGFR, KRAS, BRAF, NRAS, PIK3CA, MEK1, AKT1, and PTEN) and a PCR-based sizing assay that assesses for EGFR exon 19 deletions, EGFR exon 20 insertions, and HER2 exon 20 insertions. We detected 15 EGFR mutations [E20-6bp-ins. (n=1); EGFR_19-15bpDel (n=4); EGFR_G719A_2156G>C (n=2); EGFR_G719C_2155G>T (n=3); EGFR_G719S _2155G>T (n=1); EGFR_G719S_2155G>A (n=1); EGFR_L858R_2573T>G (n=2); EGFR L861Q_2582T>A (n=1)] in 12 ADCs and 2 SCCs. Six KRAS mutations, all of which were KRAS G12C_34G>T, were detected in 5 ADCs and 1 SCC. EGFR and KRAS mutations were mutually exclusive and no mutations were observed for BRAF, NRAS, PIK3CA, MEK1, HER2, AKT1, or PTEN. The high percentage of samples with KRAS mutations (15.0% overall; 15.6% ADCs; 14.3% SCCs) in our series is of interest, primarily because KRAS mutations are reportedly more rare in other populations from Asia (∼5%) and populations of never smokers from Asia (∼2%). Given that all subjects with KRAS mutations burned coal indoors for heating and cooking, our findings may provide new insights into the pathogenesis of lung cancer among never smoking females exposed to indoor air pollution from coal. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5479. doi:1538-7445.AM2012-5479

To the Editor. —You are to be congratulated for your outstanding edition on universal health insurance (May 15, 1991). It was well-organized and well thought out, and I deeply appreciate your attention to this topic. As one of the few politicians in this country who practices medicine, I'd like to share the following observations. There are two major faults with many of these plans. The first is that a number of them rely on continuation of the Medicare program. Any practicing physician will tell you that the Medicare program is a disaster. It underreimburses the physicians, it undercompensates the insured patients, and its bureaucracy and interference with medical practice are demoralizing. Second, the major shortcoming of many plans (including that of the American Medical Association) is the lack of serious provision for cost containment. That also applies to the Pepper Commission and many of the other plans that rely on

Mercury (Hg) is an environmental toxicant dangerous to human health and the environment. Its anthropogenic emissions are regulated by global, regional, and local policies. Here, we investigate Hg sources in the coastal city of Boston, the third largest metropolitan area in the Northeastern United States. With a median of 1.37 ng m−3, atmospheric Hg concentrations measured from August 2017 to April 2019 were at the low end of the range reported in the Northern Hemisphere and in the range reported at North American rural sites. Despite relatively low ambient Hg concentrations, we estimate anthropogenic emissions to be 3–7 times higher than in current emission inventories using a measurement-model framework, suggesting an underestimation of small point and/or nonpoint emissions. We also test the hypothesis that a legacy Hg source from the ocean contributes to atmospheric Hg concentrations in the study area; legacy emissions (recycling of previously deposited Hg) account for ∼60% of Hg emitted annually worldwide (and much of this recycling takes place through the oceans). We find that elevated concentrations observed during easterly oceanic winds can be fully explained by low wind speeds and recirculating air allowing for accumulation of land-based emissions. This study suggests that the influence of nonpoint land-based emissions may be comparable in size to point sources in some regions and highlights the benefits of further top-down studies in other areas.

Despite the key role of the Arctic in the global Earth system, year-round in-situ atmospheric composition observations within the Arctic are sparse and mostly rely on measurements at ground-based coastal stations. Measurements of a suite of in-situ trace gases were performed in the central Arctic during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition. These observations give a comprehensive picture of year-round near-surface atmospheric abundances of key greenhouse and trace gases, i.e., carbon dioxide, methane, nitrous oxide, ozone, carbon monoxide, dimethylsulfide, sulfur dioxide, elemental mercury, and selected volatile organic compounds (VOCs). Redundancy in certain measurements supported continuity and permitted cross-evaluation and validation of the data. This paper gives an overview of the trace gas measurements conducted during MOSAiC and highlights the high quality of the monitoring activities. In addition, in the case of redundant measurements, merged datasets are provided and recommended for further use by the scientific community.

DERMATOLOGISTS and physical therapists have, for many years, utilized infrared rays to counteract accidental overexposure to ultraviolet light. However, the chemical and physiological bases for this phenomenon have not been demonstrated and the fundamental nature of ultraviolet erythema has not been clarified. We became interested in studying the nature of infrared modification of ultraviolet erythema in hope that an investigation might contribute to our understanding of the physiology of the sunburn reaction. Review The 1929 study of Shattock and Waller is the only investigation we have found which concerned itself with the effect of infrared radiation on the cutaneous erythema produced by ultraviolet light. 1 In their study it was shown that the application of heat during or after, but not prior to, ultraviolet radiation diminished and delayed the appearance of the erythema reaction. More recent studies of the infrared effect on induced ultraviolet damage have either been conducted