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Abstract This study presents the first annotated, haplotype-resolved, chromosome-scale genome of Lantana camara, a flowering shrub native to Central America and known for its dual role as an ornamental plant and an invasive species. Despite its widespread cultivation and ecological impact, the lack of a high-quality genome has hindered the investigation of traits of both ornamental and invasive. This research bridges the gap in genomic resources for L. camara, which is crucial for both ornamental breeding programs and invasive species management. Whole-genome and transcriptome sequencing were utilized to elucidate the genetic complexity of a diploid L. camara breeding line UF-T48. The genome was assembled de novo using HiFi and Hi-C reads, resulting in two phased genome assemblies with high Benchmarking Universal Single-Copy Orthologs (BUSCO) scores of 97.7%, indicating their quality. All 22 chromosomes were assembled with pseudochromosomes averaging 117 Mb. The assemblies revealed 29 telomeres and an extensive presence of repetitive sequences, primarily long terminal repeat transposable elements. The genome annotation identified 83,775 protein-coding genes, with 83% functionally annotated. In particular, the study mapped 42 anthocyanin and carotenoid candidate gene clusters and 12 herbicide target genes to the assembly, identifying 38 genes spread across the genome that are integral to flower color development and 53 genes for herbicide targeting in L. camara. This comprehensive genomic study not only enhances the understanding of L. camara’s genetic makeup but also sets a precedent for genomic research in the Verbenaceae family, offering a foundation for future studies in plant genetics, conservation, and breeding.

Abstract Short-acting beta-agonist (SABA) over-use in asthma is harmful for patients and the environment. The Investment and Impact Fund (IIF) 2022/2023 financially rewarded English primary care networks that achieved specific targets, including reducing SABA over-use (RESP-02) and lowering the mean carbon footprint per salbutamol inhaler prescribed (ES-02). SENTINEL Plus is a co-designed quality improvement package that aims to improve asthma outcomes and reduce asthma’s environmental impact by addressing SABA over-use. We investigated the impact of (i) the IIF incentives and (ii) SENTINEL Plus implementation on asthma prescribing. Using Openprescribing.net data, we demonstrate that IIF 2022-2023 had no significant impact on the total number of SABA prescribed in England (25,927,252 during 12-months pre- and 25,885,213 12-months post-IIF; 0.16% decrease; p=NS), but lower carbon footprint SABA inhaler use increased (Salamol™ prescribing increased from 5.1% to 19% of SABA prescriptions, p

The discovery of triploids in caladium has raised strong interest in their use in cultivar development. For triploid production, tetraploids must first be generated from elite breeding material without the introduction of deleterious alleles like has been seen with chemical agents like colchicine and 2,4-D. To meet this new demand, virus eradicated, meristem-tip caladium cultures were grown on auxin-free media and used for generation and evaluation of new somaclonal variants. Over 12,000 micropropagated caladiums were visually screened ex vitro for sports varying from the wild-type phenotype. Eight variants from four cultivars were discovered and characterized for morphological, cytological, and molecular changes. Genome duplication occurred in seven of the variants with an average nuclear DNA content of 18.76 pg·2C−1. The tetraploid variant of cultivar ‘White Wing’ had eight more chromosomes (2n = 4x = 68) than the other tetraploids and exactly double that of its wildtype. All other diploids had the expected 2n = 2x = 30 chromosomes and tetraploids recorded 2n = 4x = 60. Tetraploids had 19% rounder leaves and 44% thicker leaves than the diploids in the study. Tetraploids also had a 49% and 31% increase in stomata length and width, respectively. Molecular marker analysis only revealed two polymorphisms with both occurring in the 'White Wing' variant. Few changes in molecular marker banding could indicate that the tetraploids discovered have a clean duplication of the genome and might effectively be used for new triploid cultivar development.

The newly released “Plant This Not That: A Guide to Avoiding Invasive Plant Species in Florida” booklet emerges as a crucial tool in cultivating a comprehensive understanding of invasive species, facilitating informed decision-making in plant selection. Its unique focus on illustrating alternatives to invasive plants, coupled with its accessible format, can empower individuals to contribute to the preservation of Florida, USA, ecosystems. The booklet’s impact was displayed through an in-service training for 58 University of Florida/Institute of Food and Agricultural Sciences extension personnel. Following the in-service training, attendees demonstrated statistically significant improvements in their perceived knowledge of four key invasive species concepts. This study highlights the booklet and accompanying training’s potential as a valuable resource for mitigating the impacts of invasive plant species.

Abstract In this work, we present the most updated catalog of Io hot spots based on Juno/JIRAM data. We find 242 hot spots, including 23 previously undetected. Over the half of the new hot spots identified, are located at high northern and southern latitudes (>70°). We observe a latitudinal variability and a larger concentration of hot spots in the polar regions, in particular in the North. The comparison between JIRAM and the most recent Io hot spot catalogs listing power output (Veeder et al., 2015, https://doi.org/10.1016/j.icarus.2014.07.028; de Kleer, de Pater, et al., 2019, https://doi.org/10.3847/1538-3881/ab2380), shows JIRAM detected 63% and 88% of the total number of hot spots, respectively. Furthermore, JIRAM observed 16 of the 34 faint hot spots previously identified. JIRAM data revealed thermal emission from 5 dark pateræ inferred to be active from color ratio images, thus confirming that these are hot spots.

Gulf vervain (Verbena xutha) is a herbaceous perennial native to the southern United States. The species produces attractive spike inflorescences that provide a source of food for many pollinators. Besides botanical classifications, pollen morphology and cytological traits of this species have not been documented until now. Gulf vervain was found to have 2n = 42 chromosomes, with the first report of 2C nuclear DNA content of 2.95 pg. Convex-triangular pollen grains averaged 37.18 μm in diameter, with 84% stainability after cotton blue staining to estimate pollen viability. This information brings light to the genetic makeup of gulf vervain and may aid in future breeding programs.

Cultivated caladium (Caladium × hortulanum; 2n = 2x = 30) is an important ornamental aroid for the environmental horticulture industry. A better understanding of its genetic diversity is needed for continued improvement of caladium. The caladium germplasm maintained in the University of Florida’s caladium breeding program were surveyed for potential variation in chromosome number and nuclear DNA content to gain a better understanding of caladium genetic diversity at the cytogenetic level. For the first time caladium triploidy was discovered in two breeding lines, UF-15-414 and UF-4407 with 2n = 3x = 45 chromosomes and a nuclear DNA content of 13.86 pg·2C−1. In addition, a new chromosome number (2n = 2x = 34) was found in one cultivar, ‘White Wing’. Compared with their diploid parents or grandparents, the triploids showed a distinct, attractive leaf morphology with rounder and thicker leaves. The pollen stainability of UF-15-414 and UF-4407 was 63% and 73%, respectively, indicating potential male fertility, which was unexpected. Analysis of simple sequence repeat (SSR) marker banding patterns confirmed that UF-15-414 was a direct progeny of UF-4407 through hybridization with the diploid cultivar Aaron, whereas UF-4407 might result from fusion of an unreduced (female or male) gamete with a reduced gamete. Chromosome counting and SSR marker analysis of ‘White Wing’ and its progeny cultivars ‘White Wonder’ and ‘White Delight’ suggested that ‘White Wing’ possibly transmitted its 34 chromosomes to progeny during sexual reproduction. The discovery and characterization of these triploids revealed the occurrence of natural sexual polyploidization in caladium and indicated good potential for creating and selecting new triploids for future caladium breeding. The observed new chromosome number in ‘White Wing’ and its progeny cultivars implies that other chromosome variations may be present among cultivated caladiums. In summary, these results revealed two male-fertile triploid caladiums and a new chromosome number that can enrich the cytogenetic diversity in future caladium cultivar development.

Education policy has long been analyzed as a cycle where various actors influence different stages. However, few such studies have focused on identifying and interrogating the specific moments that shape an education policy's overall equity trajectory. This article uses Bowe, Ball, and Gold's policy cycle as an exploratory theoretical framework, focusing on the historic "Review of Funding for Schooling" (2011) in Australia, which evaluated the nation's school funding policy. The authors concentrate on the Context of Text Production phase of its policymaking process, and consider the implications for equity. From this work, the authors highlight two "critical moments" that they argue significantly influenced how the appointed panel approached equity. Their theorizing of a "critical moment" offers valuable insights for researchers and stakeholders seeking to understand or influence education policy.

The article advances an emergent framework for conceptualizing the relationship between principal leadership and education policy implementation. Based on a qualitative study of school principals and policy implementation in Region X of the Philippines, findings suggested that the way in which policies were interpreted and implemented at the school level was influenced by a variety of intrinsic and extrinsic dynamics and these were shaped in situ by individual, school and community inhibitors and facilitators. These motivations and localized contexts were critical to implementation, and compelled principals to ignore, monitor, or implement education policies as a priority.

Lantana species are an important component of the U.S. environmental horticulture industry. The most commonly produced and used species are L. camara and, on a smaller scale, L. montevidensis. Both were introduced to the United States from Central and/or South America. Lantana species native to the continental United States include L. canescens, L. depressa, L. involucrata, etc. and most of them have not been well exploited. This study was conducted to obtain information about somatic chromosome numbers, karyotypes, and genome size of these five species. Nuclear DNA content in these species ranged from 2.74 pg/2C (L. involucrata) to 6.29 pg/2C (L. depressa var. depressa). Four chromosome numbers were observed: 2n = 2x = 22 in L. camara ‘Lola’ and ‘Denholm White’, 2n = 4x = 44 in L. depressa var. depressa, 2n = 2x = 24 in L. canescens and L. involucrata, and 2n = 3x = 36 in L. montevidensis. Two basic chromosome numbers were observed: x = 11 in L. camara and L. depressa var. depressa, and x = 12 in L. canescens, L. involucrata, and L. montevidensis. Analysis of somatic metaphases resulted in formulas of 20m + 2sm for L. camara ‘Lola’ and ‘Denholm White’, 12m + 12sm for L. canescens, 44m for L. depressa var. depressa, 10m + 14sm for L. involucrata, and 32m + 4sm for L. montevidensis. Satellites were identified in all five species, but were associated with a different chromosome group in different species. L. depressa var. depressa had the longest total chromatin length (146.78 µm) with a range of 1.88 to 4.41 µm for individual chromosomes. The maximum arm ratio was observed in L. canescens, with a ratio of 2.5 in chromosome group 3. L. depressa var. depressa was the only species that had all of its centromeres located in the median region of the chromosome. The results show significant differences in nuclear DNA content, chromosome number, and karyotype among three native and two introduced lantana species and will help to identify, preserve, protect, and use native lantana species. The information will be helpful in assessing the ploidy levels in the genus by flow cytometry.

Porterweed (Stachytarpheta spp.), a member of the verbena family, is frequently used in pollinator gardens to attract butterflies. This study was conducted to assess the morphological features, pollen stainability and morphology, nuclear DNA content, and chromosome number of five porterweed selections. Coral porterweed (S. mutabilis), ‘Naples Lilac’ porterweed (S. cayennensis × S. mutabilis ‘Violacea’), and nettleleaf porterweed (S. cayennensis) had the largest plant heights. Flower number was significantly higher in nettleleaf porterweed, jamaican porterweed (S. jamaicensis), and U*J3-2 porterweed (S. cayennensis × S. jamaicensis), with an average of 65–72 flowers per inflorescence. Internode length and flower width of jamaican porterweed had much lower values than the other selections. Coral porterweed recorded the lowest pollen stainability with only 10.6% stainability, but it had the largest relative pollen production. ‘Naples Lilac’ porterweed had the highest DNA content with an average of 3.79 pg/2C, like jamaican porterweed with 3.73 pg/2C. Ploidy levels varied between selections, and the basic chromosome number was x = 28. Coral, jamaican, and ‘Naples Lilac’ porterweed had 2n = 6x = 168 chromosomes, first reported in this genus. These results provide a guide and a new tool to distinguish native and non-native porterweed and may aid future breeding toward the production of noninvasive cultivars.

As part of a larger project focused on the intersection of educational and health trajectories over the life course, we use in-depth interviews with 28 adults who experienced multiple non-promotional school changes during the course of their K-12 schooling in three U.S. urban centers to advance understanding of frequent student mobility. Prior research focuses predominantly on isolating the impact of student mobility while saying little about processes through which mobility influences educational trajectories in particular contexts. Frequent student mobility was intertwined with adverse childhood experiences and access to coping resources, and these forces shaped participants' trajectories in patterned ways. Supporting frequently mobile students, almost a third of school-age children in the United States, will require greater attention to the reasons for, processes of, and contexts of student mobility.

The Flow Country peatlands receive national and international recognition and protection as a highly valued habitat, and also provide a number of important ecosystem services. While there has been much research on the terrestrial peatland habitat of the Flow Country, the area’s many hundreds of natural water bodies have been largely unstudied. The first part of this study therefore focuses on establishing the contemporary conditions at 18 Flow Country lakes, examining between-lake heterogeneity in terms of physical structure, water chemistry and biological communities. Temporal change in these lakes is then considered by combining contemporary ecological and palaeolimnological approaches. We examine how the diatom and chironomid communities of Flow Country lakes have changed since a time prior to the mid-nineteenth century. Results show that the lake communities today are different to those present pre-1850, containing more taxa tolerant of increased acidity and nutrient availability. General linear modelling (GLM) analysis demonstrated a statistically significant association between the extent of change in diatom communities and both dissolved organic carbon (DOC) and nitrate. Community shifts, though considerable, are shown to be complex and idiosyncratic and no shift between trophic states is indicated. The extent and type of coarse-scale community change we observed points to widespread bottom-up drivers such as land management, afforestation and/or atmospheric deposition rather than more localised management practices such as fish stocking. The benefits of combining approaches is discussed and palaeolimnological methods by which land management, afforestation and atmospheric deposition could be further disentangled are identified.

Background: Pulmonary vein (PV) reconduction after PV isolation (PVI) unmasked by adenosine is associated with a higher risk for paroxysmal atrial fibrillation (PAF) recurrence. It is unknown if the reconnected PVs after adenosine testing and immediate re-ablation can predict reconnection and reconnection patterns of PVs at repeat procedures. We assessed reconnection of PVs with and without dormant-conduction (DC) during the first and the repeat procedure. Methods: We included 67 patients undergoing PVI for PAF and a second procedure for PAF recurrence. DC during adenosine administration at first procedure was seen in 31 patients (46%). 264 PVs were tested with adenosine; DC was found in 48 PVs (18%) and re-ablated during first procedure. During the second procedure, all PVs where checked for reconnection. Results: Fifty-eight patients (87%) showed PV reconnection during the second procedure. Reconnection was found in 152/264 PVs (58%). Of 216 PVs without reconnection during adenosine testing at the first ablation, 116 PVs (53.7%) showed reconnection at the repeat procedure. Overall, 14.9% of patients showed the same PV reconnection pattern in the first and second procedure, expected statistical probability of encountering the same reconnection pattern was only 6.6%(p = 0.012). Conclusions: In repeat procedures PVs showed significantly more often the same reconnection pattern as during first procedure than statistically expected. More than 50% of initial isolated PVs without reconnection during adenosine testing showed a reconnection during repeat ablation. Techniques to detect susceptibility for PV re-connection like prolonged waiting-period should be applied. Elimination of DC should be expanded from segmental to circumferential re-isolation or vaster RF application. Keywords: Atrial fibrillation, RF ablation, Pulmonary vein isolation, Adenosine, Recurrence of atrial fibrillation

More than a buzzword, teacher burnout captures the zeitgeist of the last few years as schools grapple with the challenges of education in a post-COVID-19 pandemic world. Garwood sounds an alarm and issues a call to action to address teacher burnout given its implications on students in general and, more specifically, on its implications for the fidelity of service delivery interventions for those students most in need. Of the malleable factors related to burnout, this article focused on teachers' "capacity to manage classroom behavior" and discusses the potential of the Behavioral, Academic, and Social Engagement (BASE) Model to disrupt processes that can lead to teacher burnout. To illustrate the model's potential, we present perspectives from middle school teachers shared in focus groups about challenging classroom behaviors and their professional development needs, and we discuss how the BASE Model can help address teachers' capacity for managing their classroom context. Implications for teacher training and supported professionalism to reduce burnout are discussed.

Atmospheric chemistry and transport of mercury play a key role in the global mercury cycle. However, there are still considerable knowledge gaps concerning the fate of mercury in the atmosphere. This is the second part of a model intercomparison study investigating the impact of atmospheric chemistry and emissions on mercury in the atmosphere. While the first study focused on ground-based observations of mercury concentration and deposition, here we investigate the vertical and interhemispheric distribution and speciation of mercury from the planetary boundary layer to the lower stratosphere. So far, there have been few model studies investigating the vertical distribution of mercury, mostly focusing on single aircraft campaigns. Here, we present a first comprehensive analysis based on various aircraft observations in Europe, North America, and on intercontinental flights. The investigated models proved to be able to reproduce the distribution of total and elemental mercury concentrations in the troposphere including interhemispheric trends. One key aspect of the study is the investigation of mercury oxidation in the troposphere. We found that different chemistry schemes were better at reproducing observed oxidized mercury patterns depending on altitude. High concentrations of oxidized mercury in the upper troposphere could be reproduced with oxidation by bromine while elevated concentrations in the lower troposphere were better reproduced by OH and ozone chemistry. However, the results were not always conclusive as the physical and chemical parameterizations in the chemistry transport models also proved to have a substantial impact on model results.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Abstract Disease-modifying therapies for Alzheimer’s disease (AD) are likely to be most beneficial when initiated in the presymptomatic phase. To track the benefit of such interventions, fluid biomarkers are of great importance, with neurofilament light chain protein (NfL) showing promise for monitoring neurodegeneration and predicting cognitive outcomes. Here, we update and complement previous findings from the Dominantly Inherited Alzheimer Network Observational Study by using matched cross-sectional and longitudinal cerebrospinal fluid (CSF) and plasma samples from 567 individuals, allowing timely comparative analyses of CSF and blood trajectories across the entire disease spectrum. CSF and plasma trajectories were similar at presymptomatic stages, discriminating mutation carriers from non-carrier controls 10-20 years before the estimated onset of clinical symptoms, depending on the statistical model used. However, after symptom onset the rate of change in CSF NfL continued to increase steadily, whereas the rate of change in plasma NfL leveled off. Both plasma and CSF NfL changes were associated with grey-matter atrophy, but not with Aβ-PET changes, supporting a temporal decoupling of Aβ deposition and neurodegeneration. These observations support NfL in both CSF and blood as an early marker of neurodegeneration but suggest that NfL measured in the CSF may be better suited for monitoring clinical trial outcomes in symptomatic AD patients.

Specialized research training is a key component of graduate education, yet sexual and gender diverse (SGD) emerging scholars may not receive quality training and networking opportunities at their home institutions. International and interdisciplinary trainings by SGD scholars may develop research competence and academic networks, but few such extracurricular research training programs exist. This article presents the curriculum and mixed-method evaluation of the International Student Training Network (ISTN), a two-year bilingual training program designed to train SGD emerging scholars in Canada, the USA, Mexico, and the UK to conduct research with SGD youth. The racially diverse and interdisciplinary trainees (N = 38) completed a competence self-assessment at pre-test, midpoint, and post-test. Significant improvements in knowledge and skill were found, while importance of the concepts remained consistently high. Twelve trainees participated in interviews to reflect on their experience. Thematic analysis produced three themes, describing benefits of the ISTN: (1) 'You do stick out a lot': Fostering SGD scholarly community in academia; (2) 'We were all working together': Bridging the disciplinary and geographic gaps; and (3) 'A transformative experience': Developing scholarly self-concept and academic self-efficacy. The findings highlight the utility of specialized research training for emerging SGD scholars limited by geographical and disciplinary siloes.

Growth in the online survey market may be increasing response burden and possibly jeopardizing higher response rates. This meta-analysis evaluated survey trends over one decade (2011-2020) to determine: (1) changes in survey publication rates over time, (2) changes in response rates over time, (3) typical response rates within health sciences education research, (4) the factors influencing survey completion levels, and (5) common gaps in survey methods and outcomes reporting. Study I estimated survey publication trends between 2011 and 2020 using articles published in the top three health sciences education research journals. Study II searched the anatomical sciences education literature across six databases and extracted study/survey features and survey response rates. Time plots and a proportional meta-analysis were performed. Per 2926 research articles, the annual estimated proportion of studies with survey methodologies has remained constant, with no linear trend (p > 0.050) over time (Study I). Study II reported a pooled absolute response rate of 67% (95% CI = 63.9-69.0) across 360 studies ("k"), totaling 115,526 distributed surveys. Despite response rate oscillations over time, no significant linear trend (p = 0.995) was detected. Neither survey length, incentives, sponsorship, nor population type affected absolute response rates (p [greater than or equal to] 0.070). Only 35% (120 of 339) of studies utilizing a Likert scale reported evidence of survey validity. Survey response rates and the prevalence of studies with survey methodologies have remained stable with no linear trends over time. We recommend researchers strive for a typical absolute response rate of 67% or higher and clearly document evidence of survey validity for empirical studies.

214 neodymium permanent magnets have been manufactured for the fixed-field, multiturn return loop of the Cornell-Brookhaven Energy recovery linac Test Accelerator at Cornell University. There are 5 types of quadrupole and combined-function gradient magnets using a variant of the circular Halbach design. These are made out of NdFeB material and glued into an aluminium housing with water channels for temperature stabilization. The NdFeB wedges and magnet construction were done by outside companies, while the final “tuning” using inserts containing 64 iron rods per magnet was done at BNL over a period of about 6 months. Average relative field errors of 2.2×10^{-4} were achieved on the beam region. The magnet strengths vary by type but are of order 10 T/m for quadrupole component and up to 0.3 T for the dipole. This paper reports on the field quality and timeline achieved in this production process.

We perform global-scale inverse modeling to constrain present-day atmospheric mercury emissions and relevant physiochemical parameters in the GEOS-Chem chemical transport model. We use Bayesian inversion methods combining simulations with GEOS-Chem and ground-based Hg0 observations from regional monitoring networks and individual sites in recent years. Using optimized emissions/parameters, GEOS-Chem better reproduces these ground-based observations and also matches regional over-water Hg0 and wet deposition measurements. The optimized global mercury emission to the atmosphere is ~ 5.8 Gg yr−1. The ocean accounts for 3.2 Gg yr−1 (55 % of the total), and the terrestrial ecosystem is neither a net source nor a net sink of Hg0. The optimized Asian anthropogenic emission of Hg0 (gas elemental mercury) is 650–1770 Mg yr−1, higher than its bottom-up estimates (550–800 Mg yr−1). The ocean parameter inversions suggest that dark oxidation of aqueous elemental mercury is faster, and less mercury is removed from the mixed layer through particle sinking, when compared with current simulations. Parameter changes affect the simulated global ocean mercury budget, particularly mass exchange between the mixed layer and subsurface waters. Based on our inversion results, we re-evaluate the long-term global biogeochemical cycle of mercury, and show that legacy mercury becomes more likely to reside in the terrestrial ecosystem than in the ocean. We estimate that primary anthropogenic mercury contributes up to 23 % of present-day atmospheric deposition.

From 10 May through 17 June 2007 and 6 June through 9 July 2008 intensive sampling campaigns at Summit, Greenland confirmed that active bromine chemistry is occurring in and above the snow pack at the highest part of the Greenland ice sheet (72°36´ N, 38°25´ W and 3.2 km above sea level). Direct measurements found BrO and soluble gas phase Br− mixing ratios in the low pptv range on many days (maxima < 10 pptv). Conversion of up to 200 pg m−3 of gaseous elemental mercury (GEM) to reactive gaseous mercury (RGM) and enhanced OH relative to HO2 plus RO2 confirm that active bromine chemistry is impacting chemical cycles even at such low abundances of reactive bromine species. However, it does not appear that Bry chemistry can fully account for observed perturbations to HOx partitioning, suggesting unknown additional chemical processes may be important in this unique environment, or that our understanding of coupled NOx-HOx-Bry chemistry above sunlit polar snow is incomplete. Rapid transport from the north Atlantic marine boundary layer occasionally caused enhanced BrO at Summit (just two such events observed during the 12 weeks of sampling over the two seasons). In general observed reactive bromine was linked to activation of bromide (Br−) in, and release of reactive bromine from, the snowpack. A coupled snow-atmosphere model simulated observed NO and BrO at Summit during a three day interval when winds were weak. The source of Br− in surface and near surface snow at Summit is not entirely clear, but concentrations were observed to increase when stronger vertical mixing brought free tropospheric air to the surface. Reactive Bry mixing ratios above the snow often increased in the day or two following increases in snow concentration, but this response was not consistent. On seasonal time scales concentrations of Br− in snow and reactive bromine in the air were directly related.

We have developed a new nested-grid mercury (Hg) simulation over North America with a 1/2° latitude by 2/3° longitude horizontal resolution employing the GEOS-Chem global chemical transport model. Emissions, chemistry, deposition, and meteorology are self-consistent between the global and nested domains. Compared to the global model (4° latitude by 5° longitude), the nested model shows improved skill at capturing the high spatial and temporal variability of Hg wet deposition over North America observed by the Mercury Deposition Network (MDN) in 2008–2009. The nested simulation resolves features such as higher deposition due to orographic precipitation, land/ocean contrast and and predicts more efficient convective rain scavenging of Hg over the southeast United States. However, the nested model overestimates Hg wet deposition over the Ohio River Valley region (ORV) by 27%. We modify anthropogenic emission speciation profiles in the US EPA National Emission Inventory (NEI) to account for the rapid in-plume reduction of reactive to elemental Hg (IPR simulation). This leads to a decrease in the model bias to −2.3% over the ORV region. Over the contiguous US, the correlation coefficient (r) between MDN observations and our IPR simulation increases from 0.60 to 0.78. The IPR nested simulation generally reproduces the seasonal cycle in surface concentrations of speciated Hg from the Atmospheric Mercury Network (AMNet) and Canadian Atmospheric Mercury Network (CAMNet). In the IPR simulation, annual mean gaseous and particulate-bound Hg(II) are within 140% and 11% of observations, respectively. In contrast, the simulation with unmodified anthropogenic Hg speciation profiles overestimates these observations by factors of 4 and 2 for gaseous and particulate-bound Hg(II), respectively. The nested model shows improved skill at capturing the horizontal variability of Hg observed over California during the ARCTAS aircraft campaign. The nested model suggests that North American anthropogenic emissions account for 10–22% of Hg wet deposition flux over the US, depending on the anthropogenic emissions speciation profile assumed. The modeled percent contribution can be as high as 60% near large point sources in ORV. Our results indicate that the North American anthropogenic contribution to dry deposition is 13–20%.

We conducted the first ever mercury speciation measurements atop the Greenland ice sheet at Summit Station (Latitude 72.6° N, Longitude 38.5° W, Altitude 3200 m) in the Spring and Summer of 2007 and 2008. These measurements were part of the collaborative Greenland Summit Halogen-HOx experiment (GSHOX) campaigns investigating the importance of halogen chemistry in this remote environment. Significant levels of BrO (1–5 pptv) in the near surface air were often accompanied by diurnal dips in gaseous elemental mercury (GEM), and in-situ production of reactive gaseous mercury (RGM). While halogen (i.e. Br) chemistry is normally associated with marine boundary layers, at Summit, Greenland, far from any marine source, we have conclusively detected bromine and mercury chemistry in the near surface air. The likely fate of the formed mercury-bromine radical (HgBr) is further oxidation to stable RGM (HgBr2, HgBrOH, HgBrCl...), or thermal decomposition. These fates appear to be controlled by the availability of Br, OH, Cl, etc. to produce RGM (Hg(II)), versus the lifetime of HgBr by thermal dissociation. At Summit, the production of RGM appears to require a sun elevation angle of >5 degrees, and an air temperature of 2), requires a sun angle >5 degrees, while the formation of RGM from HgBr requires a temperature

The Greenland Summit Halogen-HOx (GSHOX) Campaign was performed in spring 2007 and summer 2008 to investigate the impact of halogens on HOx (= OH + HO2) cycling above the Greenland Ice Sheet. Chemical species including hydroxyl and peroxy radicals (OH and HO2 + RO2), ozone (O3), nitrogen oxide (NO), nitric acid (HNO3), nitrous acid (HONO), reactive gaseous mercury (RGM), and bromine oxide (BrO) were measured during the campaign. The median midday values of HO2 + RO2 and OH concentrations observed by chemical ionization mass spectrometry (CIMS) were 2.7 × 108 molec cm−3 and 3.0 × 106 molec cm−3 in spring 2007, and 4.2 × 108 molec cm−3 and 4.1 × 106 molec cm−3 in summer 2008. A basic photochemical 0-D box model highly constrained by observations of H2O, O3, CO, CH4, NO, and J values predicted HO2 + RO2 (R = 0.90, slope = 0.87 in 2007; R = 0.79, slope = 0.96 in 2008) reasonably well and under predicted OH (R = 0.83, slope = 0.72 in 2007; R = 0.76, slope = 0.54 in 2008). Constraining the model to HONO observations did not significantly improve the ratio of OH to HO2 + RO2 and the correlation between predictions and observations. Including bromine chemistry in the model constrained by observations of BrO improved the correlation between observed and predicted HO2 + RO2 and OH, and brought the average hourly OH and HO2 + RO2 predictions closer to the observations. These model comparisons confirmed our understanding of the dominant HOx sources and sinks in this environment and indicated that BrO impacted the OH levels at Summit. Although, significant discrepancies between observed and predicted OH could not be explained by the measured BrO. Finally, observations of enhanced RGM were found to be coincident with under prediction of OH.

We have developed an intrinsic resonance free circular electron accelerator. This lattice could be placed in the existing RHIC tunnel and accelerate electrons from 400 MeV to 18 GeV avoiding all major polarization loss usual in such machines.

Polar ecosystems are considered to be the last pristine environments of the earth relatively uninfluenced by human activities. Antarctica in particular, compared to the Arctic is considered to be even less affected by any kind of anthropogenic influences. Once contaminants reach the Polar Regions, their lifetime in the troposphere depends on local removal processes. Atmospheric mercury, in particular, has unique characteristics that include long-range transport to Polar Regions and the transformation to more toxic and water-soluble compounds that may potentially become bioavailable. These chemical-physical properties have placed mercury on the priority list of an increasing number of International, European and National conventions, and agreements, aimed at the protection of the ecosystems including human health (i.e. GEO, UNEP, AMAP, UN-ECE, HELCOM, OSPAR). This interest, in turn, stimulates a significant amount of research including measurements of gaseous elemental mercury reaction rate constant with atmospheric oxidants, experimental and modelling studies in order to understand the cycling of mercury in Polar Regions, and its impact to these ecosystems. Special attention in terms of contamination of Polar Regions is paid to the consequences of the springtime phenomena, referred to as "Atmospheric Mercury Depletion Events" (AMDEs), during which elemental mercury through a series of photochemically-initiated reactions involving halogens, may be converted to a reactive form that may accumulate in polar coastal, or sea ice, ecosystems. The discovery of the AMDEs, first noted in the Arctic, has also been observed at both poles and was initially considered to result in an important net input of atmospheric mercury into the polar surfaces. However, recent studies point out that complex processes take place after deposition that may result in less significant net-inputs from the atmosphere since a fraction, sometimes significant, of deposited mercury may be recycled. Therefore, the contribution of this unique reactivity occurring in polar atmospheres to the global budget of atmospheric mercury, and the role played by snow and ice surfaces of these regions, are important issues. This paper presents a review of atmospheric mercury studies conducted in the Antarctic troposphere, both at coastal locations and on the Antarctic Plateau since 1985. Our current understanding of atmospheric reactivity in this region is also presented.

It was discovered in 1995 that, during the spring time, unexpectedly low concentrations of gaseous elemental mercury (GEM) occurred in the Arctic air. This was surprising for a pollutant known to have a long residence time in the atmosphere; however conditions appeared to exist in the Arctic that promoted this depletion of mercury (Hg). This phenomenon is termed atmospheric mercury depletion events (AMDEs) and its discovery has revolutionized our understanding of the cycling of Hg in Polar Regions while stimulating a significant amount of research to understand its impact to this fragile ecosystem. Shortly after the discovery was made in Canada, AMDEs were confirmed to occur throughout the Arctic, sub-Artic and Antarctic coasts. It is now known that, through a series of photochemically initiated reactions involving halogens, GEM is converted to a more reactive species and is subsequently associated to particles in the air and/or deposited to the polar environment. AMDEs are a means by which Hg is transferred from the atmosphere to the environment that was previously unknown. In this article we review Hg research taken place in Polar Regions pertaining to AMDEs, the methods used to collect Hg in different environmental media, research results of the current understanding of AMDEs from field, laboratory and modeling work, how Hg cycles around the environment after AMDEs, gaps in our current knowledge and the future impacts that AMDEs may have on polar environments. The research presented has shown that while considerable improvements in methodology to measure Hg have been made but the main limitation remains knowing the speciation of Hg in the various media. The processes that drive AMDEs and how they occur are discussed. As well, the role that the snow pack and the sea ice play in the cycling of Hg is presented. It has been found that deposition of Hg from AMDEs occurs at marine coasts and not far inland and that a fraction of the deposited Hg does not remain in the same form in the snow. Kinetic studies undertaken have demonstrated that bromine is the major oxidant depleting Hg in the atmosphere. Modeling results demonstrate that there is a significant deposition of Hg to Polar Regions as a result of AMDEs. Models have also shown that Hg is readily transported to the Arctic from source regions, at times during springtime when this environment is actively transforming Hg from the atmosphere to the snow and ice surfaces. The presence of significant amounts of methyl Hg in snow in the Arctic surrounding AMDEs is important because this species is the link between the environment and impacts to wildlife and humans. Further, much work on methylation and demethylation processes has occurred but these processes are not yet fully understood. Recent changes in the climate and sea ice cover in Polar Regions are likely to have strong effects on the cycling of Hg in this environment; however more research is needed to understand Hg processes in order to formulate meaningful predictions of these changes.

A variational analysis of dynamics of soliton solution of coupled nonlinear Schrödinger equations with oscillating terms is made, considering a birefringent fiber with a third-order nonlinearity in the anomalous dispersion frequency region. This theoretical model predicts optical soliton oscillations in lossy fibers.

The properties of the neutrino provide a unique window on physics beyond that described by the standard model. The study of subleading effects in neutrino oscillations, and the race to discover CP-invariance violation in the lepton sector, has begun with the recent discovery that θ_{13}>0. The measured value of θ_{13} is large, emphasizing the need for a facility at which the systematic uncertainties can be reduced to the percent level. The neutrino factory, in which intense neutrino beams are produced from the decay of muons, has been shown to outperform all realistic alternatives and to be capable of making measurements of the requisite precision. Its unique discovery potential arises from the fact that only at the neutrino factory is it practical to produce high-energy electron (anti)neutrino beams of the required intensity. This paper presents the conceptual design of the neutrino factory accelerator facility developed by the European Commission Framework Programme 7 EUROν Design Study consortium. EUROν coordinated the European contributions to the International Design Study for the Neutrino Factory (the IDS-NF) collaboration. The EUROν baseline accelerator facility will provide 10^{21} muon decays per year from 12.6 GeV stored muon beams serving a single neutrino detector situated at a source-detector distance of between 1 500 km and 2 500 km. A suite of near detectors will allow definitive neutrino-scattering experiments to be performed.

Organisms can respond to rapid climatic changes in three ways: 1) adaptation by evolution, affecting physiology and morphology), 2) migration and population dynamics including biogeographical changes) and 3) extinction local or global). Here, the focus is on examples of the second type. Organisms, whether algae, trees, or animals, find their ecological niches in a multi- dimensional space of gradients such as temperature winter, summer, means or extremes), humidity soil or air), pH, various nutrients, light. Presence or absence of taxa species, genera, families) can be related to such gradients. With training sets based on current gradients, they can also be related to environmental changes of the past e. g. summer mean temperatures or pH). The relationships between the occurrence of taxa and environmental variables can also be used to examine the biotic response to changes based on other proxies, for example, changes in temperature inferred from oxygen- isotope ratios in carbonates or from the content in organic matter of lake sediments. The groups of organisms referred to here are plants pollen), insects chironomids) and other aquatic invertebrates. The three Late Glacial periods with very high rates of change in temperature estimates are the transition from the Oldest Dryas to the Bölling from GS- 2 to GI- 1 in the Late Glacial, ca. 14 670 cal yr BP), and the beginning and the end of the Younger Dryas ca. 12 600 cal yr BP, 11 500 cal yr BP respectively). The « classical » hypothesis was that trees represented in pollen diagrams) respond more slowly to climatic change than invertebrates aquatic or terrestrial) because of differences in life cycles. But it is shown here that terrestrial vegetation) and aquatic invertebrate) ecosystems may respond synchronously. Three major biological processes are involved in the responses to climatic change: 1) Migration – can be slow if, for example, a longliving tree migrated back from a southern refugium. 2) Build- up of populations – intermediate velocity, for the process needs time depending on the life cycles of the organisms. 3) Productivity – can change rapidly, within a year or a few years e. g. pollen productivity, tree rings). The first two of these processes occur on the organisational level of populations, the last one on the level of the individual. These processes develop also in various combinations.