Isoprene nitrates: preparation, separation, identification, yields, and atmospheric chemistry

Isoprene is an important atmospheric volatile organic compound involved in ozone production and NO<sub>x</sub> (NO+NO<sub>2</sub>) sequestration and transport. Isoprene reaction with OH in the presence of NO can form either isoprene hydroxy nitrates ("isoprene nitrates") or convert NO to NO<sub>2</sub> which can photolyze to form ozone. While it has been shown that isoprene nitrate production can represent an important sink for NO<sub>x</sub> in forest impacted environments, there is little experimental knowledge of the relative importance of the individual isoprene nitrate isomers, each of which has a different fate and reactivity. In this work, we have identified the 8 individual isomers and determined their total and individual production yields. The overall yield of isoprene nitrates at atmospheric pressure and 295 K was found to be 0.070(+0.025/−0.015). Three isomers, representing nitrates resulting from OH addition to a terminal carbon, represent 90% of the total IN yield. We also determined the ozone rate constants for three of the isomers, and have calculated their atmospheric lifetimes, which range from ~1–2 h, making their oxidation products likely more important as atmospheric organic nitrates and sinks for nitrogen

Controlled Cold Water and Water Slushy Ingestion, and Heat Performance in Subjects of Average Fitness

Fluid ingestion is known to improve exercise performance and could lead to a heat sink effect, if cold enough. While research has been conducted on the influence of hydration in exercise performance, little has been done which consider beverages’ temperature during controlled consumption. PURPOSE: To examine the effect of controlled consumption of water at different temperatures on heat performance in subjects of average fitness. METHODS: Fifteen males, ages 18-29, with no prior heat illness were recruited. Subjects were tested for body composition and peak oxygen consumption (VO2peak) prior to testing. All subjects underwent three experimental trials [cold water (CD=4̊C), water slushy (SL=-1̊C), room temperature water (RM=22̊C)] in a balanced crossover design. Subjects were required to exercise on a cycle ergometer at intensity 70% VO2peak (vigorous exercise) in the heat (34.0±0.6̊C, 41.7±2.7% RH, 3.6 km∙hr∙-1 wind speed) until volitional maximum. Subjects were required to consume a controlled volume (2.5 g∙kgBodyMass-1) of one of the treatments (CD, SL, RM) every 10 minutes each trial. Measurements for maximum exercise time (ExT), pre-/post-core body temperature change (ΔTc), heart rate (HR), mean skin temperature (MTsk), sweat rate (SR), and RPE were recorded. One-way (beverage) or two-way (beverage x time) ANOVA with repeated measures was used (α=0.05). RESULTS: ExT did not differ significantly between treatments (CD=33.8±9.4 min; SL=35.0±9.8 min; RM=31.5±8.6 min) but a trend (p=0.0680) was seen where SL&CD\u3eRM, which was supported by all subjects having their longest bouts during CD (n=10) and SL (n=5) trials. Neither ΔTc (CD=0.69±0.36˚C, SL=0.64±0.43˚C, RM=0.77±0.45˚C), or SR (CD=1545±1109 ml·hr-1; SL=1837±692 ml·hr-1; RM=1891±489 ml·hr-1), differed (p\u3e0.05) between treatments. A main effect for beverage was seen in HR (CD=157±16 bpm; SL=153±18 bpm; RM=160±17 bpm)(p\u3c0.05) where SLsk or RPE (p\u3e0.05). A main effect for time (p\u3c0.05) was see in HR (T20=161±18 bpm\u3eT10=153±16 bpm), MTsk (T20=36.2±0.3˚C\u3eT10=35.9±0.3˚C), and RPE (T20=5.8±2.1 (0-10)\u3eT10=3.3±1.4 (0-10)). A trend towards significant beverage x time interaction was seen for HR (p=0.0900) but treatments did not respond differently over time for MTsk or RPE (p\u3e0.05). HR at volitional maximum differed between treatments (CD=168±20 bpm; SL=165±20 bpm; RM=173±20 bpm)(p\u3c0.05), specifically SLsk or RPE (p\u3e0.05). CONCLUSION: SL appeared to improve performance over RM, but not CD. There may be a point where colder beverage temperature does not yield a greater heat sink effect or, results could have been due to shorter exercise time in subjects of average fitness

Psychological Responses Prior to a Strenuous Task Involving an Injured Joint

Injuries are an inherent risk of sport participation. Roughly 68% of athletes experience an athletic injury during their college career, with over half being injuries to the lower extremity (Hootman, Dick & Agel, 2007). While much attention has been given to the physical effects of an injury, the psychological ramifications can also affect an athlete’s recovery from injury. According to Quinn & Fallon (2008), an athlete can physically recover from an injury however they may not attain a complete psychological recovery. An athlete’s performance can be affected negatively if they return to sport participation without recovering psychologically from their injury, which can also lead to a risk of re-injury or receiving additional injuries (Quinn & Fallon, 2008). Two variables related to psychological recovery include re-establishment of confidence and a decrease in fear of re-injury (Magyar & Duda, 2000; Walker & Heaney, 2013). Additionally, an athlete may feel reluctance to perform skills that require the site of injury to be used which affects subsequent performance. An athlete’s fear of re-injury can negatively affect athletes’ performance by undermining an athlete’s confidence in obtaining their pre-injury sport performance (Arden, Taylor, Feller & Webster, 2012). The purpose of this study was to determine how psychological responses to injury, namely sport resumption confidence, fear of re-injury, and injury perception change throughout the rehabilitation process. These variables were examined in relation to performing a strenuous isokinetic dynamometer task on an injured joint (e.g., knee, ankle). Participants (N=21; 62% female) completed psychometrically sound measures designed to assess confidence, fear and injury perception across three groups of athletes: healthy (n = 9), injured (n = 6), and rehabilitated (n = 6). All subjects were told they would be completing a maximal isokinetic contraction task on the lower extremity that had been injured before completing the survey. Only healthy and rehabilitated athletes actually performed the task at the completion of the survey. ANOVA was utilized to compare group differences on study variables. There was a significant difference between groups with regard to fear (healthy=1.62 ± 0.03; injured=4.09 ± 0.10; rehabilitated=3.17 ± 0.61; p \u3c .05) and confidence (healthy=5.82 ± 0.68; injured=2.99 ± 0.06; rehabilitated=4.06 ± 0.58; p \u3c .01) where healthy athletes reported the highest confidence and lowest fear across groups. Additionally, injured athletes reported the lowest confidence and highest fear across groups. There were no group differences found with regard to injury perception (healthy=0.00 ± 0.00; injured=1.01 ± 0.41; rehabilitated=0.07 ± 0.09). This study extends the current sport injury research base by identifying changes in key psychological variables across the healthy-injured-rehabilitated continuum of the collegiate sport experience

Anthropogenic Control over Wintertime Oxidation of Atmospheric Pollutants

Anthropogenic air pollutants such as nitrogen oxides (NO(x) = NO + NO(2)), sulfur dioxide (SO(2)), and volatile organic compounds (VOC), among others, are emitted to the atmosphere throughout the year from energy production and use, transportation, and agriculture. These primary pollutants lead to the formation of secondary pollutants such as fine particulate matter (PM(2.5)) and ozone (O(3)) and perturbations to the abundance and lifetimes of short-lived greenhouse gases. Free radical oxidation reactions driven by solar radiation govern the atmospheric lifetimes and transformations of most primary pollutants and thus their spatial distributions. During winter in the mid and high latitudes, where a large fraction of atmospheric pollutants are emitted globally, such photochemical oxidation is significantly slower. Using observations from a highly instrumented aircraft, we show that multi-phase reactions between gas-phase NO(x) reservoirs and aerosol particles, as well as VOC emissions from anthropogenic activities, lead to a suite of atypical radical precursors dominating the oxidizing capacity in polluted winter air, and thus, the distribution and fate of primary pollutants on a regional to global scale

80,000,000 hooligans. Discourses of resistance to racism and xenophobia in German punk lyrics 1991-1994

The late eighties and early nineties in Germany were not only marked by the fall of the Wall and German unification, but also by the dramatization of the political issue of asylum, resulting in outbreaks of xenophobic violence. In the context of the asylum debate of the early nineties, a number of punk bands produced songs between 1991 and 1994 which criticise the xenophobic climate created by the asylum debate and undermine an exculpatory official discourse about the violent attacks. The lyrics of these songs will be analysed as instances of counter-discourse emerging from a subcultural sphere that nurtures a critical distance towards hegemonic public and political discourse, arguing that Critical Discourse Analysis should pay more attention to defiance of hegemonic discourse

Ghosts of other stories: a synthesis of hauntology, crime and space

Criminology has long sought to illuminate the lived experience of those at the margins. More recently, there has been a turn toward the spatial in the discipline. This paper sets out an analytical framework that synthesizes spatial theory with hauntology. We demonstrate how a given space's violent histories can become embedded in the texts that constitute it and the language that describes it. The art installation ‘Die Familie Schneider’ is used as an example of how the incorporation of social trauma can lead to the formation of a spatial “crypt”. Cracking open this “crypt” allows us to draw out Derrida's notion of the specter within the context of a “haunted” city space

The Aminopeptidase CD13 Induces Homotypic Aggregation in Neutrophils and Impairs Collagen Invasion.

Aminopeptidase N (CD13) is a widely expressed cell surface metallopeptidase involved in the migration of cancer and endothelial cells. Apart from our demonstration that CD13 modulates the efficacy of tumor necrosis factor-α-induced apoptosis in neutrophils, no other function for CD13 has been ascribed in this cell. We hypothesized that CD13 may be involved in neutrophil migration and/or homotypic aggregation. Using purified human blood neutrophils we confirmed the expression of CD13 on neutrophils and its up-regulation by pro-inflammatory agonists. However, using the anti-CD13 monoclonal antibody WM-15 and the aminopeptidase enzymatic inhibitor bestatin we were unable to demonstrate any direct involvement of CD13 in neutrophil polarisation or chemotaxis. In contrast, IL-8-mediated neutrophil migration in type I collagen gels was significantly impaired by the anti-CD13 monoclonal antibodies WM-15 and MY7. Notably, these antibodies also induced significant homotypic aggregation of neutrophils, which was dependent on CD13 cross-linking and was attenuated by phosphoinositide 3-kinase and extracellular signal-related kinase 1/2 inhibition. Live imaging demonstrated that in WM-15-treated neutrophils, where homotypic aggregation was evident, the number of cells entering IL-8 impregnated collagen I gels was significantly reduced. These data reveal a novel role for CD13 in inducing homotypic aggregation in neutrophils, which results in a transmigration deficiency; this mechanism may be relevant to neutrophil micro-aggregation in vivo.This work was funded by a Medical Research Council Research Training Fellowship to CAF (G0900329), Addenbrooke’s Charitable Trust (ACT), CUHNHSFT, Papworth Hospital NHS Foundation Trust and the NIHR Cambridge Biomedical Research Centre. CAF received a Raymond and Beverly Sackler Studentship.This is the final version of the article. It first appeared from the Public Library of Science via http://dx.doi.org/10.1371/journal.pone.016010

Influence of relative humidity and aging on the optical properties of organic aerosols from burning African biomass fuels

Biomass burning (BB) is a major source of atmospheric fine carbonaceous aerosols, which play a significant, yet uncertain, role in modulating the Earth’s radiation balance. However, accurately representing their optical properties in climate models remains challenging due to factors such as particle size, mixing state, combustion type, chemical composition, aging processes, and relative humidity (RH). In our study, we investigated BB organic-rich aerosols generated from smoldering sub-Saharan African biomass fuels. Fuel samples were collected in Africa and aerosols generated in the laboratory. We quantified key optical parameters, including mass cross-sections for extinction (2.04 ± 0.32 − 15.5 ± 2.48 m2/g), absorption (0.04 ± 0.01–0.3 ± 0.1 m2/g), and scattering (1.9 ± 0.68–15.3 ± 5.5 m2/g). Wavelength-dependent properties were used to determine absorption and scattering Ångström exponents. The single scattering albedo of these aerosols ranged from 0.8 ± 0.03 to 1.0 ± 0.04 and we observed a wavelength-dependent behavior. Extinction emission factors were determined at a wavelength of 550 nm, with values ranging from 42 ± 5 to 293 ± 32 m2/kg. Notably, optical properties exhibited fuel-type dependence, with differences observed between hardwood samples and other fuels, such as grass and animal dung. Aging increased mass extinction and scattering cross-sections at 550 nm, while humidity had the opposite effect across all fuels. Nitrate radical oxidation, both in photo and dark aging conditions, also influenced these properties. The findings are expected to close the gap in our understanding of optical properties of BB aerosol emissions in one of the least studied regions of the world – Africa – providing information to climate and air quality models for the region

Predicting 2-year survival in stage I-III non-small cell lung cancer: the development and validation of a scoring system from an Australian cohort

Background: There are limited data on survival prediction models in contemporary inoperable non-small cell lung cancer (NSCLC) patients. The objective of this study was to develop and validate a survival prediction model in a cohort of inoperable stage I-III NSCLC patients treated with radiotherapy. Methods: Data from inoperable stage I-III NSCLC patients diagnosed from 1/1/2016 to 31/12/2017 were collected from three radiation oncology clinics. Patient, tumour and treatment-related variables were selected for model inclusion using univariate and multivariate analysis. Cox proportional hazards regression was used to develop a 2-year overall survival prediction model, the South West Sydney Model (SWSM) in one clinic (n = 117) and validated in the other clinics (n = 144). Model performance, assessed internally and on one independent dataset, was expressed as Harrell’s concordance index (c-index). Results: The SWSM contained five variables: Eastern Cooperative Oncology Group performance status, diffusing capacity of the lung for carbon monoxide, histological diagnosis, tumour lobe and equivalent dose in 2 Gy fractions. The SWSM yielded a c-index of 0.70 on internal validation and 0.72 on external validation. Survival probability could be stratified into three groups using a risk score derived from the model. Conclusions: A 2-year survival model with good discrimination was developed. The model included tumour lobe as a novel variable and has the potential to guide treatment decisions. Further validation is needed in a larger patient cohort