bluuebunny/crossref_metadata_2025 huggingface dataset:
Root Initiation In Mukhikachu (Colocasia Esculenta)As Influenced By IAA And NAA
Authors: Bhuiyan MKR , Hossain MJ , Rahman MS , Rahman SML , Sattar MA
Published: December 2011

In vitro root initiation in Mukhikachu (Colocasia esculenta var. globulifera) was assessed in a factorial experiment using three levels of IAA (0.5, 1.0, and 2.0 mg/l), three levels of NAA (0.5, 1.0, and 2.0 mg/l) and control. Fifty percent intact shoots were used as usual, which was named as normal cut explant and the rest 50 % shoots were cut slantly to expose fresh surface i.e., cambium zone and named as slant cut explant. Low levels of IAA (0.5mg/l) initiated the roots earliest (≈14 DAC) and gave the highest percentage of root (49.71). This treatment also gave the maximum roots/culture (3.63). Root initiation was higher (61.33 %) with slant cut when cultured on a medium containing 0.5 mg/l IAA. The cultures with slant cut end also produced more number of roots and longest roots whereas, the highest root initiation (45.05 %) was given by the treatment 1.0 mg/l NAA, but 2.0 mg/I NAA gave lower percentage of roots (39.89).The maximum number of roots/culture was also obtained by 1.0 mg/l NAA. Slant cut explant performed better regarding root initiation (%), number of roots/culture and length of roots. In this experiment, slant cut explant performed better than that of normal cut and either IAA (0.05 mg/l) or NAA (1.0 mg/l) might be used for root initiation in Mukhikachu. Keywords: Root initiation; Colocasia; IAA; NAA. DOI: http://dx.doi.org/10.3329/bjar.v36i3.9276 BJAR 2011; 36(3): 487-494
Effects Of Plant Population And Bio-Fertilizer On The Growth Parameters Of Three Summer Mungbean (Vigna Radiata L.) Cultivars
Authors: Rana MM , Chowdhury AKMSH , Bhuiya MSU
Published: December 2011

Keywords: Mungbean, plant population, bio-fertilizer, growth.DOI: http://dx.doi.org/10.3329/bjar.v36i3.9281BJAR 2011; 36(3): 537-542
Discriminating Gene Expression Signature of Radiation-Induced Thyroid Tumors after Either External Exposure or Internal Contamination
Authors: Ory Catherine , Ugolin Nicolas , Schlumberger Martin , Hofman Paul , Chevillard Sylvie
Published: December 2011

Both external radiation exposure and internal radionuclide contamination are well known risk factors in the development of thyroid epithelial tumors. The identification of specific molecular markers deregulated in radiation-induced thyroid tumors is important for the etiological diagnosis since neither histological features nor genetic alterations can discriminate between sporadic and radiation-induced tumors. Identification of highly discriminating markers in radiation-induced tumors is challenging as it relies on the ability to identify marker deregulation which is associated with a cellular stress that occurred many years before in the thyroid cells. The existence of such a signature is still controversial, as it was not found in several studies while a highly discriminating signature was found in both post-radiotherapy and post-Chernobyl series in other studies. Overall, published studies searching for radiation-induced thyroid tumor specificities, using transcriptomic, proteomic and comparative genomic hybridization approaches, and bearing in mind the analytical constraints required to analyze such small series of tumors, suggest that such a molecular signature could be found. In comparison with sporadic tumors, we highlight molecular similarities and specificities in tumors occurring after high-dose external radiation exposure, such as radiotherapy, and in post-Chernobyl tumors that occurred after internal 131I contamination. We discuss the relevance of signature extrapolation from series of tumors developing after high and low doses in the identification of tumors induced at very low doses of radiation.
Diversification of the American bulb‐bearing Oxalis (Oxalidaceae): Dispersal to North America and modification of the tristylous breeding system
Authors: Gardner Andrew G. , Vaio Magdalena , Guerra Marcelo , Emshwiller Eve
Published: December 2011

• Premise of the study: The American bulb‐bearing Oxalis (Oxalidaceae) have diverse heterostylous breeding systems and are distributed in mountainous areas from Patagonia to the northeastern United States. To study the evolutionary processes leading to this diversity, we constructed the first molecular phylogeny for the American bulb‐bearing Oxalis and used it to infer biogeographic history and breeding system evolution.

• Methods: We used DNA sequence data (nuclear ribosomal internal transcribed spacer, trnL‐trnL‐trnF, trnT‐trnL, and psbJ‐petA) to infer phylogenetic history via parsimony, likelihood, and Bayesian analyses. We used Bayes Multistate to infer ancestral geographic distributions at well‐supported nodes of the phylogeny. The Shimodaira‐Hasegawa (SH) test distinguished among hypotheses of single or multiple transitions from South America to North America, and tristyly to distyly.

• Key results: The American bulb‐bearing Oxalis include sampled members of sections Ionoxalis and Pseudobulbosae and are derived from a larger clade that includes members of sections Palmatifoliae, Articulatae, and the African species. The American bulb‐bearing Oxalis comprise two clades: one distributed in SE South America and the other in the Andes and North America. An SH test supports multiple dispersals to North America. Most sampled distylous species form a single clade, but at least two other independent distylous lineages are supported by the topologies and SH tests.

• Conclusions: Phylogenetic results suggest the American bulb‐bearing Oxalis originated in southern South America, dispersed repeatedly to North America, and had multiple transitions from tristyly to distyly. This study adds to our understanding of biogeographic history and breeding system evolution and provides a foundation for more precise inferences about the study group.
CONSTRUCTION PROJECT CASH FLOW PLANNING USING THE PARETO OPTIMALITY EFFICIENCY NETWORK MODEL / STATYBOS PROJEKTO PINIGŲ SRAUTŲ PLANAVIMAS, NAUDOJANT PARETO OPTIMUMO EFEKTYVUMO TINKLO MODELĮ
Authors: Jiang Aiyin , Issa Raja R. A. , Malek Maged
Published: December 2011

Cash flow is crucial for ensuring the viability of a project. It consists of a complete history of all cash disbursement, cash shortage, loans, cost of money, and all earnings received. Although significant research work has been conducted on cash flow forecast, planning, and management, the objective is constantly the maximization of profit/final cash balance, or minimization of total project cost. Moreover, cash flow forecasting needs to be effective and fast. The paper develops multiple-objective cash flow planning model – Pareto optimality efficiency network model, which considers typical banking instruments, the constraints of the financial market, the budget constraints, and retention of money. A case study illustrates the multi-objective project cash flow management approach by applying the proposed model to a real world problem. A what-if-analysis depicts the tradeoff between profitability and loan interests, which are major issues in project cash flow planning and management. The model presents an effective decision making tool to be used by industry practitioners with reasonable accuracy.

Santrauka

Projekto gyvybingumui pinigų srautai turi kritinę reikšmę. Pinigų srautus sudaro piniginės viso projekto išlaidos, pinigų trūkumas, paskolos, pinigų kaina ir visos gautos pajamos. Nors atlikta daug pinigų srautų prognozių, planavimo ir valdymo tyrimų, jų objektas paprastai yra pelno (galutinio pinigų likučio) maksimizavimas arba bendros projekto kainos minimizavimas. Be to, pinigų srautų prognozavimas turi būti veiksmingas ir greitas. Darbe kuriamas daugiatikslis pinigų srautų planavimo modelis – Pareto optimumo efektyvumo tinklo modelis, kuris apima įprastas bankų veiklos priemones, finansų rinkos suvaržymus, biudžeto suvaržymus ir pinigų išsaugojimą. Tiriant atvejį pristatomas daugiatikslis projekto pinigų srautų valdymo metodas, t. y. taikant siūulomą modelį sprendžiamas praktinis uždavinys. Galimų variantų analizė (angl. What-if-analysis) rodo, kaip suderinti pelningumą ir paskolos palūkanas, t. y. pagrindines problemas planuojant ir valdant projekto pinigų srautus. Modelis yra gana tiksli ir efektyvi sprendimų priėmimo priemonė, skirta sektoriaus praktikams.
ENERGY EFFICIENCY CHALLENGES IN MULTI-APARTMENT BUILDING RENOVATION IN LITHUANIA / IŠŠŪKIAI ENERGIJOS VARTOJIMO EFEKTYVUMUI VYKDANT DAUGIABUČIŲ NAMŲ MODERNIZACIJĄ LIETUVOJE
Authors: Biekša Darius , Šiupšinskas Giedrius , Martinaitis Vytautas , Jaraminienė Eglė
Published: December 2011

The paper presents a position of the authors on the current setup of the multi-apartment renovation process in Lithuania. The conducted investigation includes the actual case study analysis of the group of residential buildings in Birštonas. The paper deals with three areas that have a major impact on the success of the overall renovation process. The areas include the currently applied mechanisms for identifying and evaluating energy efficiency measures, data analysis of measuring actual energy efficiency and determination of the economic feasibility of the renovation process. Research results clearly indicate that the current shape of the program scheme is far from completion. The paper produces recommendations and research findings that could be used for further improvement on the process.

Santrauka

Straipsnyje pateikta autorių pozicija dėl Lietuvoje vykdomos daugiabučių gyvenamųjų namų modernizavimo programos. Tyrimas apima grupės pastatų Birštone analizę ir orientuojasi į tris pagrindines sritis, turinčias lemiamą reikšmę bendram daugiabučių namų modernizavimo programos igyvendinimui. Šios sritys yra: taikomi energijos vartojimo efektyvumo didinimo priemonių identifikavimo ir įvertinimo mechanizmai, faktinių energijos vartojimo duomenų analizė ir pastatų modernizacijos proceso ekonominio patrauklumo vertinimas. Gautos tyrimu išvados rodo, kad daugiabučių namų modernizavimo programa yra tobulintina. Joje apibrėžiama modernizavimo projektų vykdymo ir paramos tvarka turi nemažai prieštaravimų dėl neleistinai didelių faktinių ir skaičiuotinų energijos suvartojimo nesutapimų, energijos vartojimo efektyvumo didinimo priemonių ekonominio efektyvumo nustatymo patikimumo, perdėtos veiklų rizikos koncentravimo galutiniam vartotojui ir pan. Tyrime pateikiama nustatytų problemų apžvalga ir pateikiamos rekomendacijos, kaip ką spręsti.
Parenthood and the Structuring of Time among Urban Households in Northern Italy
Authors: Ghezzi Simone
Published: December 2011

Résumé Parentalité et temporalités dans des foyers urbains dans l’Italie du Nord Le thème principal de cet article a pris forme en réfléchissant à un sujet récurrent, bien qu’inattendu – la compression du temps familial –, constamment mentionné par nos interlocuteurs lors du travail de terrain conduit dans deux sites italiens (urbain et semi-urbain). Plusieurs d’entre eux se plaignaient du temps que prenait l’enquête kass sur leur temps quotidien. Les parents comme les époux, et même les enfants, tenaient des discours très particuliers qui dominaient la discussion dès lors que nous abordions la question du temps. C’est dans ce contexte que nous avons commencé à explorer la structuration du temps parmi les différents membres de la famille.
Kinship, Community and Care: Rural-Urban Contrasts in Croatia
Authors: Leutloff-Grandits Carolin
Published: December 2011

Résumé Parenté, communauté, entraide : différences entre la ville et la campagne en Croatie Fondé sur un double terrain croate, urbain et rural, cet article analyse le rôle des parents dans la Croatie d’après le socialisme. En dépit de points communs, comme la proximité résidentielle de la proche famille et l’importance de la parentèle, deux rationalités distinctes sont en fait à l’œuvre. Dans le complexe urbain de Travno, la proximité spatiale des proches parents permet l’entraide intra-familiale, ce qui facilite l’ajustement des familles aux nouvelles demandes de flexibilité de la vie professionnelle et aux jeunes femmes d’entrer sur le marché du travail. En milieu rural, où l’emploi est plus limité, la proximité et les valeurs familiales conduisent les femmes à rester à la maison ou à s’impliquer dans une agriculture de subsistance. Celles qui ne se plient pas à ce modèle émigrent. L’importance croissante des fêtes marquant les étapes du cycle de la vie familiale, au cours desquelles se renforcent les réseaux superposés de parenté, de voisinage, d’amitié et de parrainage, contribue à la stabilisation des communautés rurales et au maintien de leur modèle de parenté spécifique.
Paternités contemporaines et nouvelles trajectoires familiales
Authors: Martial Agnès
Published: December 2011

Résumé À partir d’une recherche en cours auprès d’hommes séparés ou divorcés élevant leurs enfants selon différentes modalités résidentielles, cet article interroge les clivages sociaux et sexués traversant la paternité « en solitaire », tout en l’envisageant à travers différentes temporalités (quotidienne, biographique et générationnelle).
The Social Politics of Fatherhood in Spain and France: a Comparative Analysis of Parental Leave and Shared Residence
Authors: Escobedo Anna , Flaquer Lluís , Navarro-Varas Lara
Published: December 2011

Résumé Les politiques sociales de la paternité en France et en Espagne : une analyse comparée du congé parental et de la résidence partagée L’article présente une analyse comparative de l’évolution des politiques relatives aux congés paternels et à la garde conjointe en Espagne et en France dans la dernière décennie. Ces deux mesures sont toutes deux largement reconnues comme instruments importants de la promotion de nouveaux styles de paternité et par conséquent d’une plus grande égalité entre hommes et femmes dans l’Union européenne. Alors que la rhétorique du choix a été développée dans les deux pays en matière d’emploi de la mère et de garde d’enfants, avec de meilleurs résultats en France qu’en Espagne, il reste à voir dans quelle mesure la possibilité de choix sera aussi ouverte aux pères.
Paternités en solitaire : ruptures conjugales et logiques d'insertion sociale
Authors: Orain Renaud
Published: December 2011

Résumé Les parcours de vie des pères « en solitaire » sont divers, tant au regard des situations matérielles que des relations post-rupture et de leur encadrement judiciaire. À partir d’une enquête de terrain en région parisienne réalisée en 2009-2010, nous étudions les conditions sociales et économiques qui affectent la manière dont les hommes peuvent ou non jouer un rôle suffisant ou légitime à leur propres yeux dans la vie de leurs enfants et dans son organisation.
Paternité et sexualité dans la construction de soi
Authors: Tarnovski Flávio Luiz
Published: December 2011

Résumé Paternité et homosexualité ont pendant longtemps été considérées comme des expériences contradictoires. La visibilité récente des familles homoparentales commence à produire des changements en direction d’une conjugaison positive de ces deux expériences. À partir de l’analyse des récits des pères homosexuels ayant eu leurs enfants dans une union hétérosexuelle, il s’agira de problématiser l’articulation entre orientation sexuelle et désir de paternité.
Vulvar basal cell carcinoma: report of a case involving the mucosa and review of the literature
Authors: Caucanas Marie , Müller Gebhard , Vanhooteghemv Olivier
Published: December 2011

We report the case of woman who presented a vulvar basal cell carcinoma (BCC) on the inner part of the labium majus, treated with local resection. Vulvar BCC is a rare cancer but can be long misdiagnosed due to a non-specific presentation. Though even rarer, BCC involving the mucosal side of the labium majus has to be considered in the differential diagnosis of the vulvar tumors. A complete excision with free margins is the treatment most recommended. Other recommendations include the early identification of aggressive subtypes, which carry a greater risk of recurrence and spreading potential as well as a long-term follow-up with exhaustive muco-cutaneous examination.
Formulation and evaluation of colon targeted tablets containing simvastatin solid dispersion
Authors: Abd Elbary Ahmed , Ibrahim Howida K. , Hazaa Balquees S.
Published: December 2011

Solid dispersions (SDs) of simvastatin with mannitol, Ineutic®, Pluronic® F-68, PEG 4000 and PVP K-30 were prepared and evaluated to deliver simvastatin to the colon in a pre-solubilized form. The formula of choice was compressed into fast disintegrating tablets using drug compatible excipients and was coated with Eudragit® S100 as a pH-responsive polymer. We investigated the effects of several variables related to both SD preparation (carrier type, combined carriers and drug to carrier ratio) and tablet coating (coat level and type of plasticizer) on drug dissolution. Differential scanning caloremitry (DSC) and scanning electron microscopy (SEM) proved drug amorphization in SDs. The 1:5 simvastatin/ Pluronic® SDs showed the greatest improvement in dissolution efficiency (12.2-fold) at the lowest carrier ratio. The coating level was critical for determining the duration of the lagphase. Best results were given by the 10% coat (20:2:1 w/w Eudragit S100/ triethylcitrate/ talc). This formula resisted pre-colonic pH values and showed an adequate lag time for the intended colonic targeting (4 h), followed by an immediate release phase (t50%=249 min) in pH 7.4. The proposed coated tablets may provide a colonic delivery system for simvastatin with improved bioavailability.
Field guide for monitoring shoreline change, fortress of Louisbourg National Historical Site, Nova Scotia
Authors: Taylor R B , Frobel D , Brown A O , Duggan R , Reeves L
Published: December 2011

This field guide is an updated version of a 1996 Shoreline Monitoring report for Fortress Louisbourg Historical Site. It is designed to assist park staff in locating specific shore sites and line markers for accurately measuring shoreline change following severe
storms or during routine patrols. Location maps, sketches, photos, GPS coordinates of markers and tables are provided for examining and recording changes at each shore site. Deterioration and loss of markers at a number of shore sites during the past few years and a focus by archaeologists on newly
exposed cultural resources on Rochefort Point and along Louisbourg Harbour necessitated this revision. Additional sites were added in 2011 at White Point and Battery Island. Any information collected or changes observed at any of these sites should be reported to the archaeological group at Fortress
Louisbourg for inclusion in their computer data base and assessment of shoreline changes.
Health Fitness Training Responses of Normotensive and Elevated Normotensive Children
Authors: Brandon L. Jerome , Fillingim Jacqueline
Published: December 2011

The purpose of this study was to compare health fitness profiles of normotensive (blood pressure < 108/76) and elevated normotensive (blood pressure ≥ 108/76) children and to evaluate the health fitness training responses of children with higher and lower blood pressures to a regular program of exercise over an eight month period. The subjects were 386 fourth grade students (lower blood pressures = 305; higher blood pressures = 81). They were measured for height and weight and evaluated before and after an exercise intervention program for flexibility, muscular endurance, cardiovascular endurance, and body fat levels. The results show that children with higher blood pressures were fatter and had lower cardiovascular fitness levels before and after the intervention. They had health fitness profiles similar to hypertensive adults. Their rate of health fitness improvement, with training, was similar to children with lower blood pressures. Therefore, elevated normotensive children have an increased risk of cardiovascular disease but can change their risk profile with regular exercise.
The Relationship between Socioeconomic Status and Household Smoking Patterns in Canada
Authors: Millar W. J. , Hunter L.
Published: December 2011

This report uses data from a 1986 Labour Force Survey (LFS) smoking supplement to examine the relationship between education and smoking prevalence within Canadian households and the influence of parental smoking behavior on the smoking behavior of their children. The sample was a national probability sample of 14,469 households and 30,000 respondents.

Over one in two (54 %) Canadian children are exposed to the presence of at least one adult smoker in the household. Parents and children within lower socioeconomic groups are more likely to be regular smokers than their counterparts in upper socioeconomic groups. Children in lower socioeconomic households are three times more likely to be exposed to a family environment in which both parents smoke than children in upper socioeconomic level households. At all socioeconomic levels, there is a gradient in the smoking prevalence among youth and young adults according to parental smoking behavior.

The patterns of smoking within households suggest the possibility of increasing divergence in smoking rates between socioeconomic groups. The findings are discussed in terms of epidemiological and health promotion implications.
Weight Change among Registered Nurses in a Self-Help Smoking Cessation Program
Authors: Gritz Ellen R. , Berman Barbara A. , Read Laura L. , Marcus Alfred C. , Siau Jessie
Published: December 2011

Weight-related beliefs, attitudes, and patterns of weight change were analyzed for 144 registered nurses followed for one year in a self-help smoking cessation study. Smoking history and outcome status, physical descriptors, weight orientation, and use of self-help smoking cessation materials were examined in relation to weight change. A multiple regression analysis which included all subjects yielded three predictors of weight gain: continuous abstainer smoking status, lower body mass index, and greater fear of weight gain. A logistic regression confirmed the influence of smoking status at outcome on weight change. Abstinence was associated with weight gain; continuous abstainers were more likely to gain weight (88.2%) than noncontinuous abstainers (50%) and never quitters (35.9%). Weight variables were found to be interrelated, forming an “eating orientation” linked to smoking behavior.
Cardiovascular Fitness and Absenteeism in 8,301 Employed Adults
Authors: Tucker Larry A. , Aldana Steven G. , Friedman Glenn M.
Published: December 2011

The purpose of this study was to determine the extent of the relationship between cardiovascular fitness and absenteeism in the workplace. A total of 8,301 adult males and females who were employed by corporations which participated in a health screening program were used in the study. Absenteeism due to illness, demographic variables, and smoking status were assessed using a written questionnaire, while body fat was measured using skinfold calipers and cardiovascular fitness was assessed using a step test. Results indicated that high levels of cardiovascular fitness were associated significantly with low levels of absenteeism. The relationship remained strong after adjusting for differences in age, gender, income, cigarette smoking, and percent body fat. The association was stronger in females than males.
Correlates of Anger Symptoms in Women in Middle Adulthood
Authors: Thomas Sandra P. , Donnellan Madge M.
Published: December 2011

Background.

Anger is of great interest to health professionals due to its relationship with disease outcomes. However, male samples have been used in most studies examining linkages between anger and health indicators. In this exploratory study, anger symptoms and their cognitive and environmental correlates were examined in a sample of 87 women in middle adulthood.

Methods.

This descriptive-correlational study involved secondary analyses of data obtained in the third phase of a longitudinal study of health in middle adulthood. Data were collected with a battery of well-established self-report instruments. Descriptive statistics, t tests, and correlational and regression analysis were used.

Results.

Significant correlates of anger symptoms included lower optimism, external health locus of control, higher frequency and severity of daily hassles, lower functional social support, and loss of important relationship(s) during the past year. Greater body mass index, inadequate sleep, lack of exercise, drinking, and use of over-the-counter drugs were also associated with anger symptomatology.

Discussion.

Findings regarding the relationship of daily stress and anger were consistent with the Framingham Study. Contrary to expectations, women who reported more anger symptoms were not suppressors of their anger but directed it outward.
Efficiency of Printed Materials in Worksite Health Promotion
Authors: Kishchuk Natalie , Anbar Frida , O'Loughlin Jennifer , Masson Paule , Sacks-Silver Gloria
Published: December 2011

Background.

Printed health promotion materials are widely believed to be an efficient means of achieving basic health promotion objectives, such as increasing knowledge of risk factors. This study examined the efficiency of cardiovascular health promotion leaflets in reaching employees in a heterogeneous sample of worksites.

Methods.

Two types of distribution were used: copies of the leaflets were either made available centrally or distributed to each individual employee. Interviews were conducted with 272 employees in six worksites. Respondents were asked whether they recognized, had read, and had learned something from the leaflets.

Results.

Only one-quarter of respondents recognized the leaflets and only 14% stated that they had learned something. The efficiency of the leaflets was therefore much lower than expected. Z-tests for proportions showed that recognition, reading, and learning were significantly greater among those employees who had been given individual copies of the material. Among those who had been given individual copies, 45 % reported recognizing the leaflet, 36% reading it, and 23% learning something from it. Among those who had only central access, the respective scores were 11%, 7% and 6%.

Discussion.

These results suggest that the potential cost-effectiveness of printed materials such as leaflets and brochures should be weighed against alternative forms of intervention, given specific program objectives and characteristics of the target population. They also suggest that the cost and effort required in organizing the distribution of individual copies may be recouped in greater penetration.
Implementing SNOMED CT for Quality Reporting: Avoiding Pitfalls
Authors: Wade G.
Published: December 2011

Objective: To implement the SNOMED CT electronic specifications for reporting quality measures and to identify critical issues that affect implementation.

Background: The Centers for Medicare and Medicaid (CMS) have issued the electronic specifications for reporting quality measures requiring vendors and hospital systems to use standardized data elements to provide financial incentives for eligible providers.

Methods: The electronic specifications from CMS were downloaded and extracted. All SNOMED CT codes were examined individually as part of the creation of a mapping table for distribution by a vendor for incorporation into electronic health record systems. A qualitative and quantitative evaluation of the SNOMED CT codes was done as a follow up to the mapping project.

Results: A total of 10643 SNOMED codes were examined for the 44 measures. The approved SNOMED CT code sets contain aberrancies in content such as incomplete IDs, the use of description IDs instead of concept IDs, inactive codes, morphology and observable codes for clinical findings and the inclusion of non-human content.

Conclusion: Implementers of these approved specifications must do additional rigorous review and make edits in order to avoid incorporating errors into their EHR products and systems.
Seasonal variations in aerosol particle composition at the puy-de-Dôme research station in France
Authors: Freney E. J. , Sellegri K. , Canonaco F. , Boulon J. , Hervo M. , Weigel R. , Pichon J. M. , Colomb A. , Prévôt A. S. H. , Laj P.
Published: December 2011

Abstract. Detailed investigations of the chemical and microphysical properties of atmospheric aerosol particles were performed at the puy-de-Dôme (pdD) research station (1465 m) in autumn (September and October 2008), winter (February and March 2009), and summer (June 2010) using a compact Time-of-Flight Aerosol Mass Spectrometer (cToF-AMS). Over the three campaigns, the average mass concentrations of the non-refractory submicron particles ranged from 10 μg m−3 up to 27 μg m−3. Highest nitrate and ammonium mass concentrations were measured during the winter and during periods when marine modified airmasses were arriving at the site, whereas highest concentrations of organic particles were measured during the summer and during periods when continental airmasses arrived at the site. The measurements reported in this paper show that atmospheric particle composition is strongly influenced by both the season and the origin of the airmass. The total organic mass spectra were analysed using positive matrix factorisation to separate individual organic components contributing to the overall organic particle mass concentrations. These organic components include a low volatility oxygenated organic aerosol particle (LV-OOA) and a semi-volatile organic aerosol particle (SV-OOA). Correlations of the LV-OOA components with fragments of m/z 60 and m/z 73 (mass spectral markers of wood burning) during the winter campaign suggest that wintertime LV-OOA are related to aged biomass burning emissions, whereas organic aerosol particles measured during the summer are likely linked to biogenic sources. Equivalent potential temperature calculations, gas-phase, and LIDAR measurements define whether the research site is in the planetary boundary layer (PBL) or in the free troposphere (FT)/residual layer (RL). We observe that SV-OOA and nitrate particles are associated with air masses arriving from the PBL where as particle composition measured from RL/FT airmasses contain high mass fractions of sulphate and LV-OOA. This study provides unique insights into the effects of season and airmass variability on regional aerosol particles measured at an elevated site.
Contrasting winter and summer VOC mixing ratios at a forest site in the Western Mediterranean Basin: the effect of local biogenic emissions
Authors: Seco R. , Peñuelas J. , Filella I. , Llusià J. , Molowny-Horas R. , Schallhart S. , Metzger A. , Müller M. , Hansel A.
Published: December 2011

Abstract. Atmospheric volatile organic compounds (VOCs) are involved in ozone and aerosol generation, thus having implications for air quality and climate. VOCs and their emissions by vegetation also have important ecological roles as they can protect plants from stresses and act as communication cues between plants and between plants and animals. In spite of these key environmental and biological roles, the reports on seasonal and daily VOC mixing ratios in the literature for Mediterranean natural environments are scarce. We conducted seasonal (winter and summer) measurements of VOC mixing ratios in an elevated (720 m a.s.l.) holm oak Mediterranean forest site near the metropolitan area of Barcelona (NE Iberian Peninsula). Methanol was the most abundant compound among all the VOCs measured in both seasons. While aromatic VOCs showed almost no seasonal variability, short-chain oxygenated VOCs presented higher mixing ratios in summer, presumably due to greater emission by vegetation and increased photochemistry, both enhanced by the high temperatures and solar radiation in summer. Isoprenoid VOCs showed the biggest seasonal change in mixing ratios: they increased by one order of magnitude in summer, as a result of the vegetation's greater physiological activity and emission rates. The maximum diurnal concentrations of ozone increased in summer too, most likely due to more intense photochemical activity and the higher levels of VOCs in the air. The daily variation of VOC mixing ratios was mainly governed by the wind regime of the mountain, as the majority of the VOC species analyzed followed a very similar diel cycle. Mountain and sea breezes that develop after sunrise advect polluted air masses to the mountain. These polluted air masses had previously passed over the urban and industrial areas surrounding the Barcelona metropolitan area, where they were enriched in NOx and in VOCs of biotic and abiotic origin. Moreover, these polluted air masses receive additional biogenic VOCs emitted in the local valley by the vegetation, thus enhancing O3 formation in this forested site. The only VOC species that showed a somewhat different daily pattern were monoterpenes because of their local biogenic emission. Isoprene also followed in part the daily pattern of monoterpenes, but only in summer when its biotic sources were stronger. The increase by one order of magnitude in the concentrations of these volatile isoprenoids highlights the importance of local biogenic summer emissions in these Mediterranean forested areas which also receive polluted air masses from nearby or distant anthropic sources.
Reactive nitrogen, ozone and ozone production in the Arctic troposphere and the impact of stratosphere-troposphere exchange
Authors: Liang Q. , Rodriguez J. M. , Douglass A. R. , Crawford J. H. , Olson J. R. , Apel E. , Bian H. , Blake D. R. , Brune W. , Chin M. , Colarco P. R. , da Silva A. , Diskin G. S. , Duncan B. N. , Huey L. G. , Knapp D. J. , Montzka D. D. , Nielsen J. E. , Pawson S. , Riemer D. D. , Weinheimer A. J. , Wisthaler A.
Published: December 2011

Abstract. We use aircraft observations obtained during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) mission to examine the distributions and source attributions of O3 and NOy in the Arctic and sub-Arctic region. Using a number of marker tracers, we distinguish various air masses from the background troposphere and examine their contributions to NOx, O3, and O3 production in the Arctic troposphere. The background Arctic troposphere has a mean O3 of ~60 ppbv and NOx of ~25 pptv throughout spring and summer with CO decreasing from ~145 ppbv in spring to ~100 ppbv in summer. These observed mixing ratios are not notably different from the values measured during the 1988 ABLE-3A and the 2002 TOPSE field campaigns despite the significant changes in emissions and stratospheric ozone layer in the past two decades that influence Arctic tropospheric composition. Air masses associated with stratosphere-troposphere exchange are present throughout the mid and upper troposphere during spring and summer. These air masses, with mean O3 concentrations of 140–160 ppbv, are significant direct sources of O3 in the Arctic troposphere. In addition, air of stratospheric origin displays net O3 formation in the Arctic due to its sustainable, high NOx (75 pptv in spring and 110 pptv in summer) and NOy (~800 pptv in spring and ~1100 pptv in summer). The air masses influenced by the stratosphere sampled during ARCTAS-B also show conversion of HNO3 to PAN. This active production of PAN is the result of increased degradation of ethane in the stratosphere-troposphere mixed air mass to form CH3CHO, followed by subsequent formation of PAN under high NOx conditions. These findings imply that an adequate representation of stratospheric NOy input, in addition to stratospheric O3 influx, is essential to accurately simulate tropospheric Arctic O3, NOx and PAN in chemistry transport models. Plumes influenced by recent anthropogenic and biomass burning emissions observed during ARCTAS show highly elevated levels of hydrocarbons and NOy (mostly in the form of NOx and PAN), but do not contain O3 higher than that in the Arctic tropospheric background except some aged biomass burning plumes sampled during spring. Convection and/or lightning influences are negligible sources of O3 in the Arctic troposphere but can have significant impacts in the upper troposphere in the continental sub-Arctic during summer.
Characterization of the inter-annual, seasonal, and diurnal variations of condensation particle concentrations at Neumayer, Antarctica
Authors: Weller R. , Minikin A. , Wagenbach D. , Dreiling V.
Published: December 2011

Abstract. Continuous condensation particle (CP) observations were conducted from 1984 through 2009 at Neumayer Station under stringent contamination control. During this period, the CP concentration (median 258 cm−3) showed no significant long term trend but exhibited a pronounced seasonality characterized by a stepwise increase starting in September and reaching its annual maximum of around 103 cm−3 in March. Minimum values below 102 cm–3 were observed during June/July. Dedicated time series analyses in the time and frequency domain revealed no significant correlations between inter-annual CP concentration variations and atmospheric circulation indices like Southern Annular Mode (SAM) or Southern Ocean Index (SOI). The impact of the Pinatubo volcanic eruption and strong El Niño events did not affect CP concentrations. From thermodenuder experiments we deduced that the portion of volatile (at 125 °C) and semi-volatile (at 250 °C) particles which could be both associated with biogenic sulfur aerosol, was maximum during austral summer, while during winter non-volatile sea salt particles dominated. During September through April we could frequently observe enhanced concentrations of ultrafine particles within the nucleation mode (between 3 nm and 7 nm particle diameter), preferentially in the afternoon.
Projecting future HFC-23 emissions
Authors: Miller B. R. , Kuijpers L. J. M.
Published: December 2011

Abstract. A Reference Case (RC) scenario for emissions of HFC-23 from co-production during HCFC-22 manufacture over the next 25 years is presented. Offered as a template rather than a prediction, this model projects current production practices and existing abatement frameworks to yield insights into how atmospheric composition and radiative forcing might change with and without additional efforts to constrain HFC-23 emissions. Assuming that no additional abatement measures are implemented, emissions for year 2035 in this Reference Case would rise to 24 ktonnes yr−1, (cf., 8.6 ktonnes yr−1 in 2009), the atmospheric abundance of HFC-23 would rise to 50 ppt, which is a 121 % increase over the 2009 observed abundance, and HFC-23 would be expected to contribute a radiative forcing of 9 mW m−2 (cf., 4 mW m−2 in 2009). Under such a scenario, the HFC-23 emission growth rate would be a continuation of the historical trend of ∼0.2 ktonnes yr−2 until 2030, after which the growth is projected to quadruple as the Montreal Protocol phase-out of HCFC production for dispersive use concludes and HFC-23 thermal decomposition in the projects of the Clean Development Mechanism (CDM) comes to a scheduled end while growth in the production of HCFC-22 for feedstock use continues to climb with projected GDP growth. Two opposite variations regarding the future renewal of CDM projects are examined for their impact on projected emissions and abundance, relative to the Reference Case scenario.
The isotopic composition of methane in the stratosphere: high-altitude balloon sample measurements
Authors: Röckmann T. , Brass M. , Borchers R. , Engel A.
Published: December 2011

Abstract. The isotopic composition of stratospheric methane has been determined on a large suite of air samples from stratospheric balloon flights covering subtropical to polar latitudes and a time period of 16 yr. 154 samples were analyzed for δ13C and 119 samples for δD, increasing the previously published dataset for balloon borne samples by an order of magnitude, and more than doubling the total available stratospheric data (including aircraft samples) published to date. The samples also cover a large range in mixing ratio from tropospheric values near 1800 ppb down to only 250 ppb, and the strong isotope fractionation processes accordingly increase the isotopic composition up to δ13C = −14‰ and δD = +190‰, the largest enrichments observed for atmospheric CH4 so far. When analyzing and comparing kinetic isotope effects (KIEs) derived from single balloon profiles, it is necessary to take into account the residence time in the stratosphere in combination with the observed mixing ratio and isotope trends in the troposphere, and the range of isotope values covered by the individual profile. The isotopic composition of CH4 in the stratosphere is affected by both chemical and dynamical processes. This severely hampers interpretation of the data in terms of the relative fractions of the three important sink mechanisms (reaction with OH, O(1D) and Cl). It is shown that a formal sink partitioning using the measured data severely underestimates the fraction removed by OH, which is likely due to the insensitivity of the measurements to the kinetic fractionation in the lower stratosphere. Full quantitative interpretation of the CH4 isotope data in terms of the three sink reactions requires a global model.
Towards space based verification of CO2 emissions from strong localized sources: fossil fuel power plant emissions as seen by a CarbonSat constellation
Authors: Velazco V. A. , Buchwitz M. , Bovensmann H. , Reuter M. , Schneising O. , Heymann J. , Krings T. , Gerilowski K. , Burrows J. P.
Published: December 2011

Abstract. Carbon dioxide (CO2) is the most important man-made greenhouse gas (GHG) that cause global warming. With electricity generation through fossil-fuel power plants now being the economic sector with the largest source of CO2, power plant emissions monitoring has become more important than ever in the fight against global warming. In a previous study done by Bovensmann et al. (2010), random and systematic errors of power plant CO2 emissions have been quantified using a single overpass from a proposed CarbonSat instrument. In this study, we quantify errors of power plant annual emission estimates from a hypothetical CarbonSat and constellations of several CarbonSats while taking into account that power plant CO2 emissions are time-dependent. Our focus is on estimating systematic errors arising from the sparse temporal sampling as well as random errors that are primarily dependent on wind speeds. We used hourly emissions data from the US Environmental Protection Agency (EPA) combined with assimilated and re-analyzed meteorological fields from the National Centers of Environmental Prediction (NCEP). CarbonSat orbits were simulated as a sun-synchronous low-earth orbiting satellite (LEO) with an 828-km orbit height, local time ascending node (LTAN) of 13:30 (01:30 p.m. LT) and achieves global coverage after 5 days. We show, that despite the variability of the power plant emissions and the limited satellite overpasses, one CarbonSat has the potential to verify reported US annual CO2 emissions from large power plants (≥5 Mt CO2 yr−1) with a systematic error of less than ~4.9% and a random error of less than ~6.7% for 50% of all the power plants. For 90% of all the power plants, the systematic error was less than ~12.4% and the random error was less than ~13%. We additionally investigated two different satellite configurations using a combination of 5 CarbonSats. One achieves global coverage everyday but only samples the targets at fixed local times. The other configuration samples the targets five times at two-hour intervals approximately every 6th day but only achieves global coverage after 5 days. From the statistical analyses, we found, as expected, that the random errors improve by approximately a factor of two if 5 satellites are used. On the other hand, more satellites do not result in a large reduction of the systematic error. The systematic error is somewhat smaller for the CarbonSat constellation configuration achieving global coverage everyday. Therefore, we recommend the CarbonSat constellation configuration that achieves daily global coverage.
Integration of remote sensing data and surface observations to estimate the impact of the Russian wildfires over Europe and Asia during August 2010
Authors: Mei L. , Xue Y. , de Leeuw G. , Guang J. , Wang Y. , Li Y. , Xu H. , Yang L. , Hou T. , He X. , Wu C. , Dong J. , Chen Z.
Published: December 2011

Abstract. A series of wildfires broke out in Western Russia starting in late July of 2010. Harmful particulates and gases released into the local Russian atmosphere have been reported, as have possible negative consequences for the global atmosphere. In this study, an extremely hazy area and its transport trajectory on Russian wildfires were analysed using aerosol optical depth (AOD) images retrieved via the synergy method from Moderate Resolution Imaging Spectroradiometer (MODIS) data. In addition, we used trace gases (NO2 and SO2) and CO2 products measured using Ozone Monitoring Instrument (OMI) data, vertical distribution of AOD data retrieved from Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data, the mass trajectory analyses, synoptic maps from a HYSPLIT model simulation and ground-based data, including AERONET (both AOD and Ångström exponent) data and PM2.5. First, an Optimal Smoothing (OS) scheme was used to develop more precise and reliable AOD data based on multiple competing predictions made using several AOD retrieval models; then, integrated AOD and PM2.5 data were related using a chemical transport model (GEOS-Chem), and the integrated AOD and visibility data were related using the 6S radiative transfer code. The results show that the PM2.5 concentration is enhanced by a factor of 3–5 as determined from both satellite and in situ observations with peak daily mean concentrations of approximately 500 μg m3. Also, the visibility in many parts of Russia, for instance in Moscow, was less than 100 m; in some areas, the visibility was less than 50 m. Additionally, the possible impact on neighbouring countries due to long-transport was analysed for 31 July and 15 August 2010. A comparison of the satellite aerosol products and ground observations from the neighbouring countries suggests that wildfires in Western Russian had little impact on most european and asian countries, the exceptions being Finland, Estonia, Ukraine and Kyrgyzstan. However, a possible impact on the Arctic region was identified; such an effect would have a serious influence on the polar atmospheric enviroment, and on animals such as polar bears.