bluuebunny/crossref_metadata_2025 huggingface dataset:
Indicator mineral abundance data for bedrock, till and stream sediment samples from the Pine Point Mississippi Valley-Type Zn-Pb deposits, Northwest Territories
Authors: McClenaghan M B , Oviatt N M , Averill S A , Paulen R C , Gleeson S A , McNeil R
J , McCurdy M W , Paradis S , Rice J M
Published: December 2012

Till, stream sediment and bedrock samples from and around the Pine Point Zn-Pb mine district in the Northwest Territories were collected to determine the indicator minerals and their trace element signatures that are indicative of Mississippi Valley-Type
deposits. The purpose of this open file is to report the raw indicator mineral weight and abundance data for bedrock, till and stream sediment samples collected in 2010 and 2011 for this case study. Samples were processed by the commercial lab Overburden Drilling Management Limited, Ottawa, using a
combination of tabling, panning and heavy liquids to recover potential indicator minerals. Sample locations, weights of various fractions produced during sample processing and indicator mineral grains identified are reported in this open file.
The theological paraphrasing of history: The Exodus tradition in the Wisdom of Solomon
Authors: Bosman Hendrik L.
Published: November 2012

This study of the reinterpretation of the exodus tradition in the Wisdom of Solomon investigated the possibility that the reinterpretation entailed the alignment of history and wisdom. To come to grips with this alignment, attention had to be paid to its Greco-Roman context, whilst also taking into consideration the literary and theological structure of the Wisdom of Solomon, as well as its rhetoric and genre. In a theologically creative manner, Wisdom (as divine personification) and history (as memories of salvation during the Exodus) were combined in the Wisdom of Solomon to convince the Jews in the diaspora that justice would prevail – not only in this life but also thereafter. By means of poetic imagery, rhetorical skill, historical reinterpretation and imaginative wisdom theology, religious identity were not only bolstered to resist a dominant Greco-Roman culture but also to develop a positive view of creation according to the values of wisdom exemplified by the reinterpreted Exodus traditions.
Molecular cloning, characterization and expression patterns of heat shock protein 60 (HSP60) in the laying duck (Anas platyrhynchos)
Authors: Wang Deqian , Lu Lizhi , Tian Yong , Li Jinjun , Shen Junda , Tao Zhengrong , Li Guoqing , Xu Ningying
Published: November 2012

Wang, D., Lu, L., Tian, Y., Li, J., Shen, J., Tao, Z., Li, G. and Xu, N. 2012. Molecular cloning, characterization and expression patterns of heat shock protein 60 (HSP60) in the laying duck (Anas platyrhynchos). Can. J. Anim. Sci. 92: 425–432. In the present study, we cloned and characterized the HSP60 cDNA from Anas platyrhyncho (designated as ApHSP60) using a combination of homology and rapid amplification of cDNA ends (RACE). The full-length of ApHSP60 is 2027 bp in length, with an open reading frame of 1707 bp encoding a putative protein of 569 amino acids. Comparison of amino acid sequences of HSP60 revealed ApHSP60 is highly conserved, especially in the domains of classical HSP60 family signatures. ApHSP60 transcripts were at low expression levels throughout embryo development. ApHSP60 transcripts were constitutively expressed in all tested tissues of untreated laying duck, with a maximum level in the liver. Fluorescent real-time quantitative reverse transcription-polymerase chain reaction was applied to determine ApHSP60 expression after exposure to different thermal shocks. Under long term treatment with both 30°C and 35°C, ApHSP60 transcripts in heart and liver were significantly up-regulated. Otherwise, ApHSP60 transcripts were remarkably down-regulated in heart and liver under acute challenge with 40°C (a fatal temperature for laying duck). A time-dependent expression pattern of ApHSP60 was found in the recovery period after heat shock reaction. ApHSP60 expression levels in liver and heart were immediately up-regulated to the maximum at 1 h post-challenge, and then decreased to pre-challenge levels by 2 h and 3 h post-challenge, respectively. These results suggest that mRNA expression of the ApHSP60 gene is constitutive and inducible. Meanwhile, it plays an important role in response to heat stressors.
Performance and total tract nutrient digestibility of growing pigs fed hulless low phytate barley
Authors: Woyengo T. A. , Akinremi O. O. , Rossnagel B. G. , Nyachoti C. M.
Published: November 2012

Woyengo, T. A., Akinremi, O. O., Rossnagel, B. G. and Nyachoti, C. M. 2012. Performance and total tract nutrient digestibility of growing pigs fed hulless low phytate barley. Can. J. Anim. Sci. 92: 505–511. An experiment was conducted to determine the performance and nutrient digestibility of growing pigs fed hulless low phytate (HLP) barley without or with phytase for 28 d. Twenty-four growing pigs (average initial body weight=25.3 kg) were fed three diets in a completely randomised design. The diets included a regular-hulled barley-based diet, and a HLP barley-based diet without or with phytase at 500 phytase units kg−1. Pigs fed the HLP barley-based diet without phytase had greater (P<0.05) average daily gain (0.911 vs. 0.717 kg), and apparent total tract digestibility of dry matter, energy, P, Mg, and Na were higher (P<0.05) than the regular barley-based diet. Supplementation of phytase to the HLP barley-based diet resulted in improved (P<0.05) feed conversion efficiency (0.506 vs. 0.547 kg kg−1), and apparent total tract digestibility of N, P and K. In conclusion, pigs fed the HLP barley-based diet had higher growth performance and nutrient digestibility than those fed the regular-hulled barley-based diet, indicating that the HLP barley is a better source of nutrients for pigs than regular barley. Phytase supplementation to the HLP barley-based diet can result in a further increase in nutrient utilisation by pigs.
Effects of feeding 10% rapeseed meal (Brassica napus) during gestation and lactation over three reproductive cycles on the performance of hyperprolific sows and their litters
Authors: Quiniou N. , Quinsac A. , Crépon K. , Evrard J. , Peyronnet C. , Bourdillon A. , Royer E. , Etienne M.
Published: November 2012

Quiniou, N., Quinsac, A., Crépon, K., Evrard, J., Peyronnet, C., Bourdillon, A., Royer, E. and Etienne, M. 2012. Effects of feeding 10% rapeseed meal (Brassica napus) during gestation and lactation over three reproductive cycles on the performance of hyperprolific sows and their litters. Can. J. Anim. Sci. 92: 513–524. Largely due to increased production of biodiesel, there is a greater availability of solvent-extracted rapeseed meal (RM) in France, making it competitive for feeding pigs. Nevertheless, the long-term effects of dietary glucosinolates (GSL) when feeding RM on sow reproductive and litter performance are a persistent concern to feed manufacturers. Four batches of 24 hyperprolific sows were fed to evaluate the effects of including 0 or 10% RM [14.5 µmol GLS g−1dry matter (DM) basis] in the gestation and lactation diets over three reproductive cycles. Intake of dietary GLS remained below 5 mmol d−1over the gestation period and averaged 8 mmol d−1over the lactation period, corresponding to less than 2 µmol GLS g−1DM basis. Lactation feed intake, sow body weight and backfat, and the length of the weaning-to-estrus interval were not different (P>0.05) between treatment groups. Sows fed diets with 10% or no RM farrowed 43.6 and 43.8 piglets over three reproductive cycles, respectively (P>0.05). Piglet weight at birth or weaning, survival and litter weight gain were not affected (P>0.05) by dietary RM inclusion. Similar (P>0.10) plasma thyroxin levels of sows and piglets indicated that thyroid function was not altered by RM inclusion. In conclusion, feeding gestation and lactation diets including 10% RM to hyper prolific sows over three parities was safe and did not affect sow longevity, reproductive or litter performance.
Blindness in Smoky Joe roosters results in advanced sexual maturation
Authors: Perttula Jennifer , Bédécarrats Grégoy Y.
Published: November 2012

Perttula, J. and Bédécarrats, G. Y. 2012. Blindness in Smoky Joe roosters results in advanced sexual maturation. Can. J. Anim. Sci. 92: 483–491. In chickens, an increase in photoperiod activates the hypothalamo-pituitary gonadal axis resulting in sexual maturation. Although it is well established that light can directly stimulate the hypothalamus, the relative contribution of the eye in the control of reproduction is still controversial. Using a genetically blind line of chickens (Smoky Joe), we investigated the relative importance of the retina of the eye in sexual maturation in roosters. Furthermore, to evaluate the effect of photostimulation, three generations of blind and sighted Smoky Joe roosters were utilize. Generation 1 (G1) was photostimulated at 17 wk of age, while generation 2 (G2) was left un-photostimulated and generation 3 (G3) was photostimulated at 12 wk of age. Blind roosters in G1 and G2 matured between 17 and 19 wk of age (testicular weight, comb length) independently of photostimulation whereas maturation of sighted animals was significantly delayed in G2. However, this advanced sexual maturation was no longer evident when birds were stimulated at 12 wk of age. Blind roosters in G2 showed advanced spermatogenesis when compared with sighted animals. No significant difference in plasma testosterone levels was observed for any of the three generations. In conclusion, although still photosensitive, blind rooster sexually matured spontaneously earlier than their sighted counterpart.
Farm practices as they affect NH3 emissions from beef cattle
Authors: Sheppard S. C. , Bittman S.
Published: November 2012

Sheppard, S. C. and Bittman, S. 2012. Farm practices as they affect NH 3 emissions from beef cattle. Can. J. Anim. Sci. 92: 525–543. Beef cattle farms in Canada are very diverse, both in size and management. Because the total biomass of beef cattle in Canada is larger than any other livestock sector, beef also has the potential for the largest environmental impact. In this study we estimate NH3 emissions associated with beef cattle production across Canada using data on farm practices obtained from a detailed survey answered by 1380 beef farmers in 11 Ecoregions. The farms were various combinations of cow/calf, backgrounding and finishing operations. The proportion of animals on pasture varied markedly among Ecoregions, especially for cows and calves, and this markedly affected the estimated NH3 emissions. The crop components of feed also varied among Ecoregions, but the resulting crude protein concentrations were quite consistent for both backgrounding and finishing cattle. Manure was stored longer in the west than in the east, and fall spreading of manure was notably more common in the west, especially when spread on tilled land. The estimated NH3 emissions per animal were relatively consistent across Ecoregions for confinement production, but because the proportion of animals on pasture varied with Ecoregion, so did the overall estimated NH3 emissions per animal. Temperature is a key factor causing Ecoregion differences, although husbandry and manure management practices are also important. Hypothetical best management practices had little ability to reduce overall emission estimates, and could not be implemented without detailed cost/benefit analysis.
Short Communication:Escherichia coliO157 bacteriophages: lytic activity and effects on fermentation in ruminal batch culture
Authors: Bach S. J. , Cook S. R. , Wang Y. , Stanford K. , Johnson R. , McAllister T. A.
Published: November 2012

Bach, S. J., Cook, S. R., Wang, Y., Stanford, K., Johnson, R. P. and McAllister, T. A. 2012. Short Communication: Escherichia coli O157 bacteriophages: lytic activity and effects on fermentation in ruminal batch culture. Can. J. Anim. Sci. 92: 545–550. The effect of three lytic Escherichia coli O157, rV5, wV8 and wV11 on in vitro pH, gas production and dry matter disappearance in bovine ruminal cultures were assessed. None of the bacteriophages altered any of the measured parameters in ruminal fluid from concentrate or forage-fed animals. All bacteriophages were able to persist in ruminal fluid from forage and concentrate-fed cattle over a 24-h period; however, lytic activity against E. coli O157:H7 in ruminal batch cultures was not evident.
Red River 1861 Roundup Ready™ high erucic acid, low glucosinolate summer rape
Authors: McVetty P. B. E. , Duncan R. W. , Fernando W. G. D. , Li G. , Zelmer C. D.
Published: November 2012

McVetty, P. B. E., Duncan, R. W., Fernando, W. G. D., Li, G. and Zelmer, C. D. 2012. Red River 1861 Roundup Ready™ high erucic acid, low glucosinolate summer rape. Can. J. Plant Sci. 92: 1407–1409. Red River 1861 summer rape (Brassica napus L.) is the world's fourth Roundup Ready™ high erucic acid, low glucosinolate cultivar. On average, Red River 1861 yielded 19% more seed, 7 g kg−1 more seed oil and 7 g kg −1 more meal protein than MillenniUM 03 high erucic acid, low glucosinolate summer rape. Red River 1861 has an erucic acid content of 52.6% in isolated field trials of HEAR lines and is adapted to the southern B. napus growing regions of western Canada.
On Generating Optimal Sparse Probabilistic Boolean Networks with Maximum Entropy from a Positive Stationary Distribution
Authors: Jiang Hao , Chen Xi , Qiu Yushan , Ching Wai-Ki
Published: November 2012

To understand a genetic regulatory network, two popular mathematical models, Boolean Networks (BNs) and its extension Probabilistic Boolean Networks (PBNs) have been proposed. Here we address the problem of constructing a sparse Probabilistic Boolean Network (PBN) from a prescribed positive stationary distribution. A sparse matrix is more preferable, as it is easier to study and identify the major components and extract the crucial information hidden in a biological network. The captured network construction problem is both ill-posed and computationally challenging. We present a novel method to construct a sparse transition probability matrix from a given stationary distribution. A series of sparse transition probability matrices can be determined once the stationary distribution is given. By controlling the number of nonzero entries in each column of the transition probability matrix, a desirable sparse transition probability matrix in the sense of maximum entropy can be uniquely constructed as a linear combination of the selected sparse transition probability matrices (a set of sparse irreducible matrices). Numerical examples are given to demonstrate both the efficiency and effectiveness of the proposed method.
A Randomized, Double-Blind, Controlled Trial of the 17D Yellow Fever Virus Vaccine Given in Combination with Immune Globulin or Placebo: Comparative Viremia and Immunogenicity
Authors: Edupuganti Srilatha , Eidex Rachel B. , Keyserling Harry , Akondy Rama S. , Lanciotti Robert , Orenstein Walter , del Rio Carlos , Pan Yi , Querec Troy , Lipman Harvey , Barrett Alan , Ahmed Rafi , Teuwen Dirk , Cetron Martin , Mulligan Mark J.
Published: December 2012

We evaluated whether coadministration of the yellow fever (YF) virus vaccine with human immunoglobulin (Ig) that contained YF virus-neutralizing antibodies would reduce post-vaccination viremia without compromising immunogenicity and thus, potentially mitigate YF vaccine-associated adverse events. We randomized 80 participants to receive either YF vaccine and Ig or YF vaccine and saline placebo. Participants were followed for 91 days for safety and assessments of viremia and immunogenicity. There were no differences found between the two groups in the proportion of vaccinated participants who developed viremia, seroconversion, cluster of differentiation (CD)-8+ and CD4+ T-cell responses, and cytokine responses. These results argue against one putative explanation for the increased reporting of YF vaccine side effects in recent years (i.e., a change in travel clinic practice after 1996 when hepatitis A prophylaxis with vaccine replaced routine use of pre-travel Ig, thus potentially removing an incidental YF vaccine-attenuating effect of anti-YF virus antibodies present in Ig) (ClinicalTrials.gov identifier: NCT00254826).
Leprosy and Tuberculosis Co-Infection: Clinical and Immunological Report of Two Cases and Review of the Literature
Authors: Trindade Maria Ângela B. , Miyamoto Denise , Benard Gil , Sakai-Valente Neusa Y. , Vasconcelos Dewton de M. , Naafs Bernard
Published: December 2012

A review of the records of patients seen between 2004 and 2011 at the Dermatology Clinic of the São Paulo University Medical School showed that only two leprosy patients had been co-infected with tuberculosis (TB). One patient showed a type 1 leprosy reaction during the first 3 months of treatment of pleural TB and in the other patient, pulmonary TB was diagnosed during the first 3 months of treatment of a type 1 leprosy reaction. Both patients showed normal cellular immune response tests, including those of the interferon-gamma (IFN-γ)/interleukin 12 (IL-12) axis. Although both mycobacterial infections are endemic in developing countries like Brazil, the co-infection has hardly been reported in the last decade. There is no suitable explanation for this observation. The reports on the interaction between the two mycobacteria are highly speculative: some studies suggest that leprosy, especially the anergic form, would predispose to TB, whereas other investigations suggested an antagonism between the two diseases.
The system of local supply of stone tools in Amzabegovo-Vršnik culture from Neolithic Macedonia
Authors: Dimitrovska Vasilka
Published: November 2012

"Although the number of Neolithic sites excavated in the territory of the Republic of Macedonia is considerable, the stone tools pertinent to these sites are still less known because they have never interested investigators. The results of surveys in the Kratovo-Zletovo area and analyses of stone assemblages from several archaeological sites of the Amzabegovo-Vršnik culture point to a system of local supply for stone tools used by the local communities. The aim of this paper is to draw attention to areas abundant in lithic raw materials and suggest that they were local sources for the production of stone artefacts in the Amzabegovo-Vršnik culture in Neolithic Macedonia.
A technological study of Hassuna culture ceramics (Yarim Tepe I settlement)
Authors: Petrova Natalia Yu.
Published: November 2012

The article presents the results of a comparative technological analysis of Hassuna culture pottery from Yarim Tepe I (6th millennium BC) from the lower and middle horizons. The technological stages of selecting the clay and organic materials, the composition of the clay paste and the surface treatment, but also certain issues related to the ornamentation and firing of the pottery are presented in the article.
Not meant to last: mobility and disposable pottery
Authors: Gibbs Kevin
Published: November 2012

Discussions of the emergence of pottery have often focused on the development of durable vessels among sedentary societies. However, there is increasing appreciation of the fact that early pottery was sometimes used by mobile groups, such as Late Pleistocene hunter-gatherers in East Asia and perhaps Late Neolithic pastoral nomads in the Near East. Pottery that was not intended to have a long use-life, i.e. disposable pottery, could have been used to resolve some of the conflicts between pottery production and a mobile way of life, including scheduling conflicts, length of production episodes, portability and scale of production.
Towards reassessing the Neolithisation process in Western Iran
Authors: Darabi Hojjat
Published: November 2012

The multi-proxy evidence from Lake Zeribar indicates the possible impact of the Younger Dryas on Western Iran. By the end of this episode, the region was affected by rising temperatures and ensuing environmental enrichment, which could have resulted in changes in the settlement pattern from mobility to more sedentism c. 9500 BC. It is proposed that semi-sedentism led to population growth and ensuing food management in the region, which finally encouraged people to domesticate plants and animals around 8000 BC. This paper will briefly discuss the three ‘why’, ‘how’ and ‘when’ questions in investigating the Neolithisation process in western Iran.
Clinician Perceptions of Pediatric Growth Chart Use and Electronic Health Records in Kentucky
Authors: Vyas K. , Perry B. , Soares N.
Published: November 2012

Background: Growth chart recording is a key component of pediatric care. EHR systems could provide several growth charting functionalities compared to paper methods. To our knowledge, there has been no U.S. study exploring clinicians’ perceptions and practices related to recording of growth parameters as they adapt to electronic methods.

Objectives: To explore clinician practices regarding recording growth parameters as they adapt to electronic health records (EHR) and to investigate clinician perceptions of electronic growth charting using EHR.

Methods: An online survey of pediatricians and family practitioners in Kentucky inquiring about EHR usage, specifically use of growth charting with EHR, was conducted.

Results: Forty-six percent of respondents utilized EHRs, with pediatricians lagging family practitioners, and academic pediatricians lagging non-academicians. There was no consensus on EHR platforms being used. Almost a third of those who used EHR did not utilize electronic growth charting. Clinicians using EHR reported that electronic growth charts would improve clinician satisfaction and clinical efficiency as well as parent satisfaction and parent education. Only 12% of respondents provided copies of growth charts to parents at the end of their visit and discussed growth parameters with parents, with clinicians using EHR more likely to engage in these activities than nonEHR users.

Conclusion: Although Kentucky clinicians continue to slowly adopt EHRs, clinician perceptions and practices reflect enduring barriers to widespread use of electronic growth charting in pediatric and family practice. However, our results suggest that electronic growth charting has important benefits for both clinicians and patients, and greater adoption is expected as EHRs become standard across health care systems.

Citation: Soares N, Vyas K, Perry B. Clinician perceptions of pediatric growth chart use and electronic health records in Kentucky. Appl Clin Inf 2012; 3: 437–447

http://dx.doi.org/10.4338/ACI-2012-06-RA-0023
Assessment of the efficacy of laser biostimulation and low-frequency pulsed magnetic field in the treatment of microvascular abnormalities in patients with Raynaud’s phenomenon
Authors: Kuryliszyn-Moskal Anna , Kita Jacek , Dakowicz Agnieszka , Klimiuk Piotr , Kowal-Bielecka Otylia
Published: December 2012

Wstęp: Objaw Raynauda (Raynaud’s phenomenon – RP) charakteryzuje się dużą różnorodnością obrazu klinicznego, uwarun-kowanego stopniem zaawansowania zaburzeń mikrokrążenia. Kapilaroskopia wałów paznokciowych jest najlepszą nieinwazyjną metodą badania i monitorowania zaburzeń mikrokrążenia. Wobec braku satysfakcjonujących wyników leczenia farmakologicznego terapia fizykalna stanowi cenną możliwość poprawy jakości życia pacjentów z RP.

Cel pracy: Ocena klinicznego efektu terapii z zastosowaniem biostymulacji laserowej oraz impulsowego pola magnetycznego niskiej częstotliwości u 48 pacjentów z pierwotnym RP leczonych pentoksyfiliną (tab. I).

Materiał i metody: Ocenę kliniczną oraz badanie kapilaroskopowe przeprowadzono przed terapią, po 3 tygodniach leczenia pentoksyfiliną oraz po 3 tygodniach stosowania zabiegów fizykote-rapeutycznych. Po 3 tygodniach leczenia pentoksyfiliną losowo wyodrębniono dwie grupy, po 24 osoby każda, w których przez kolejne 3 tygodnie stosowano dodatkowo fizykoterapię. W obu grupach zabiegi stosowano 5 dni w tygodniu. W pierwszej grupie chorzy otrzymywali biostymulację laserową (częstotliwość 1500 Hz, dawka 25 J/cm2, czas trwania zabiegu 2,5 min). Pacjenci z drugiej grupy otrzymywali po zabiegu biostymulacji laserowej pole magnetyczne niskiej częstotliwości (40 Hz, indukcja 1–5 mT, czas trwania sesji 10–20 min).

Wyniki: Po 3 tygodniach leczenia pentoksyfiliną różnice w liczbie epizodów RP i ich intensywności nie osiągnęły znamienności statystycznej. Mimo że po zastosowaniu fizykoterapii znamienną poprawę kliniczną wykazano u wszystkich pacjentów, nie stwier-dzono istotnych różnic pomiędzy pacjentami po dwóch rodzajach terapii a pacjentami, którzy otrzymywali jedynie biostymulację laserową. Ponadto po zastosowaniu fizykoterapii wykazano poprawę w zakresie zaburzeń mikrokrążenia w badaniu kapilaroskopowym (ryc. 1–3).

Wnioski: W pracy wykazano korzystny efekt kliniczny biostymulacji laserowej u pacjentów z objawem Raynauda, leczonych pentoksyfiliną, aczkolwiek terapia z zastosowaniem pola magnetycznego niskiej częstotliwości nie miała dodatkowego wpływu na poprawę kliniczną. Po zabiegach fizykoterapeutycznych obserwowano również poprawę w zakresie zaburzeń mikrokrążenia w badaniu kapilaroskopowym.
Role of endothelial progenitor cells and redox potential in synovium neovascularisation
Authors: Rzodkiewicz Przemysław , Gajewski Michał , Maśliński Sławomir , Wojtecka-Łukasik Elżbieta
Published: December 2012

Zwiększona neowaskularyzacja błony maziowej jest jednym z istotnych elementów patomechanizmu rozwoju reumatoidalnego zapalenia stawów (RZS). Jednym z czynników mających znaczenie w przebiegu tego procesu jest produkcja wolnych rodników tlenowych, które wpływają zarówno na proces neowaskularyzacji, jak i na metabolizm endotelialnych komórek progenitorowych. Zaburzenia związane z produkcją wolnych rodników tlenowych w przebiegu zapalenia mogą być więc nie tylko bezpośrednią przyczyną uszkodzeń obserwowanych w przebiegu RZS, lecz także czynnikiem wpływającym na przebieg choroby. W niniejszej publikacji przedstawiono stan aktualnej wiedzy na temat procesu neowaskularyzacji, ze szczególnym omówieniem znaczenia potencjału redoks.
A new multi-gas constrained model of trace gas non-homogeneous transport in firn: evaluation and behaviour at eleven polar sites
Authors: Witrant E. , Martinerie P. , Hogan C. , Laube J. C. , Kawamura K. , Capron E. , Montzka S. A. , Dlugokencky E. J. , Etheridge D. , Blunier T. , Sturges W. T.
Published: December 2012

Abstract. Insoluble trace gases are trapped in polar ice at the firn-ice transition, at approximately 50 to 100 m below the surface, depending primarily on the site temperature and snow accumulation. Models of trace gas transport in polar firn are used to relate firn air and ice core records of trace gases to their atmospheric history. We propose a new model based on the following contributions. First, the firn air transport model is revised in a poromechanics framework with emphasis on the non-homogeneous properties and the treatment of gravitational settling. We then derive a nonlinear least square multi-gas optimisation scheme to calculate the effective firn diffusivity (automatic diffusivity tuning). The improvements gained by the multi-gas approach are investigated (up to ten gases for a single site are included in the optimisation process). We apply the model to four Arctic (Devon Island, NEEM, North GRIP, Summit) and seven Antarctic (DE08, Berkner Island, Siple Dome, Dronning Maud Land, South Pole, Dome C, Vostok) sites and calculate their respective depth-dependent diffusivity profiles. Among these different sites, a relationship is inferred between the snow accumulation rate and an increasing thickness of the lock-in zone defined from the isotopic composition of molecular nitrogen in firn air (denoted δ15N). It is associated with a reduced diffusivity value and an increased ratio of advective to diffusive flux in deep firn, which is particularly important at high accumulation rate sites. This has implications for the understanding of δ15N of N2 records in ice cores, in relation with past variations of the snow accumulation rate. As the snow accumulation rate is clearly a primary control on the thickness of the lock-in zone, our new approach that allows for the estimation of the lock-in zone width as a function of accumulation may lead to a better constraint on the age difference between the ice and entrapped gases.
Variability in upwelling across the tropical tropopause and correlations with tracers in the lower stratosphere
Authors: Abalos M. , Randel W. J. , Serrano E.
Published: December 2012

Abstract. Temporal variability of the upwelling near the tropical tropopause on daily to annual timescales is investigated using three different estimates computed from the ERA-Interim reanalysis. These include upwelling archived by the reanalysis, plus estimates derived from thermodynamic and momentum balance calculations. Substantial variability in upwelling is observed on both seasonal and sub-seasonal timescales, and the three estimates show reasonably good agreement. Tropical upwelling should exert strong influence on temperatures and on tracers with large vertical gradients in the lower stratosphere. We test this behavior by comparing the calculated upwelling estimates with observed temperatures in the tropical lower stratosphere, and with measurements of ozone and carbon monoxide (CO) from the Aura Microwave Limb Sounder (MLS) satellite instrument. Time series of temperature, ozone and CO are well correlated in the tropical lower stratosphere, and we quantify the influence of tropical upwelling on this joint variability. Strong coherent annual cycles observed in each quantity are found to reflect the seasonal cycle in upwelling. Statistically significant correlations between upwelling, temperatures and tracers are also found for sub-seasonal timescales, demonstrating the importance of upwelling in forcing transient variability in the lower tropical stratosphere.
Aerosol cloud activation in summer and winter at puy-de-Dôme high altitude site in France
Authors: Asmi E. , Freney E. , Hervo M. , Picard D. , Rose C. , Colomb A. , Sellegri K.
Published: December 2012

Abstract. Cloud condensation nuclei (CCN) size distributions and numbers were measured for the first time at Puy-de-Dôme high altitude (1465 m a.s.l) site in Central France. Majority of the measurements were done at constant supersaturation (SS) of 0.24%, which was also deduced to be representative of the typical in-cloud SS at the site. CCN numbers during summer ranged from about 200 up to 2000 cm−3 and during winter from 50 up to 3000 cm−3. Variability of CCN number was explained by both particle chemistry and size distribution variability. The higher CCN concentrations were measured in continental, in contrast to marine, air masses. Aerosol CCN activity was described with a single hygroscopicity parameter κ. Range of this parameter was 0.29 ± 0.13 in summer and 0.43 ± 0.19 in winter. When calculated using SS of 0.51% during summer, κ of 0.22 ± 0.07 was obtained. The decrease with increasing SS is likely explained by the particle size dependent chemistry with smaller particles containing higher amounts of freshly emitted organic species. Higher κ values during winter were for the most part explained by the observed aged organics (analysed from organic m/z 44 ratio) rather than from aerosol organic to inorganic volume fraction. The obtained κ values also fit well within the range of previously proposed global continental κ of 0.27 ± 0.21. During winter, the smallest κ values and the highest organic fractions were measured in marine air masses. CCN closure using bulk AMS chemistry led to positive bias of 5% and 2% in winter and summer, respectively. This is suspected to stem from size dependent aerosol organic fraction, which is underestimated by using AMS bulk mass composition. Finally, the results were combined with size distributions measured from interstitial and whole air inlets to obtain activated droplet size distributions. Cloud droplet number concentrations were shown to increase with accumulation mode particle number, while the real in-cloud SS correspondingly decreased. These results provide evidence on the effects of aerosol particles on maximum cloud supersaturations. Further work with detailed characterisation of cloud properties is proposed in order to provide more quantitative estimates on aerosol effects on clouds.
Investigating the long-term evolution of subtropical ozone profiles applying ground-based FTIR spectrometry
Authors: García O. E. , Schneider M. , Redondas A. , González Y. , Hase F. , Blumenstock T. , Sepúlveda E.
Published: November 2012

Abstract. This study investigates the long-term evolution of subtropical ozone profile time series (1999–2010) obtained from ground-based FTIR (Fourier Transform InfraRed) spectrometry at the Izaña Observatory ozone super-site. Different ozone retrieval strategies are examined, analysing the influence of an additional temperature retrieval and different constraints. The theoretical assessment reveals that the FTIR system is able to resolve four independent ozone layers with a precision of better than 6% in the troposphere and of better than 3% in the lower, middle and upper stratosphere. This total error includes the smoothing error, which dominates the random error budget. Furthermore, we estimate that the measurement noise as well as uncertainties in the applied atmospheric temperature profiles and instrumental line shape are leading error sources. We show that a simultaneous temperature retrieval can significantly reduce the total random errors and that a regular determination of the instrumental line shape is important for producing a consistent long-term dataset. These theoretical precision estimates are empirically confirmed by daily intercomparisons with Electro Chemical Cell (ECC) sonde profiles. In order to empirically document the long-term stability of the FTIR ozone profile data we compare the linear trends and seasonal cycles as obtained from the FTIR and ECC time series. Concerning seasonality, in winter both techniques observe stratospheric ozone profiles that are typical middle latitude profiles (low tropopause, low ozone maximum concentrations) and in summer/autumn profiles that are typical tropical profiles (high tropopause, high maximum concentrations). The linear trends estimated from the FTIR and the ECC datasets agree within their error bars. For the FTIR time series, we observe a significant negative trend in the upper troposphere/lower stratosphere of about −0.2% yr−1 and a significant positive trend in the middle and upper stratosphere of about +0.3% yr−1 and +0.4% yr−1, respectively. Identifying such small trends is a difficult task for any measurement technique. In this context, super-sites applying different techniques are very important for the detection of reliable ozone trends.
Total OH reactivity measurements using a new fast Gas Chromatographic Photo-Ionization Detector (GC-PID)
Authors: Nölscher A. C. , Sinha V. , Bockisch S. , Klüpfel T. , Williams J.
Published: December 2012

Abstract. The primary and most important oxidant in the atmosphere is the hydroxyl radical (OH). Currently OH sinks, particularly gas phase reactions, are poorly constrained. One way to characterize the overall sink of OH is to measure directly the ambient loss rate of OH, the total OH reactivity. To date, direct measurements of total OH reactivity have been either performed using a Laser-Induced Fluorescence (LIF) system ("pump-and-probe" or "flow reactor") or the Comparative Reactivity Method (CRM) with a Proton-Transfer-Reaction Mass Spectrometer (PTR-MS). Both techniques require large, complex and expensive detection systems. This study presents a feasibility assessment for CRM total OH reactivity measurements using a new detector, a Gas Chromatographic Photoionization Detector (GC-PID). Such a system is smaller, more portable, less power consuming and less expensive than other total OH reactivity measurement techniques. Total OH reactivity is measured by the CRM using a competitive reaction between a reagent (here pyrrole) with OH alone and in the presence of atmospheric reactive molecules. The new CRM method for total OH reactivity has been tested with parallel measurements of the GC-PID and the previously validated PTR-MS as detector for the reagent pyrrole during laboratory experiments, plant chamber and boreal field studies. Excellent agreement of both detectors was found when the GC-PID was operated under optimum conditions. Time resolution (60–70 s), sensitivity (LOD 3–6 s−1) and overall uncertainty (25% in optimum conditions) for total OH reactivity were similar to PTR-MS based total OH reactivity measurements. One drawback of the GC-PID system was the steady loss of sensitivity and accuracy during intensive measurements lasting several weeks, and a possible toluene interference. Generally, the GC-PID system has been shown to produce closely comparable results to the PTR-MS and thus in suitable environments (e.g. forests) it presents a viably economical alternative for groups interested in total OH reactivity observations.
Observations of NO in the upper mesosphere and lower thermosphere during ECOMA 2010
Authors: Hedin J. , Rapp M. , Khaplanov M. , Stegman J. , Witt G.
Published: November 2012

Abstract. In December 2010 the last campaign of the German-Norwegian sounding rocket project ECOMA (Existence and Charge state Of Meteoric smoke particles in the middle Atmosphere) was conducted from Andøya Rocket Range in northern Norway (69° N, 16° E) in connection with the Geminid meteor shower. The main instrument on board the rocket payloads was the ECOMA detector for studying meteoric smoke particles (MSPs) by active photoionization and subsequent detection of the produced charges (particles and photoelectrons). In addition to photoionizing MSPs, the energy of the emitted photons from the ECOMA flash-lamp is high enough to also photoionize nitric oxide (NO). Thus, around the peak of the NO layer, at and above the main MSP layer, photoelectrons produced by the photoionization of NO are expected to contribute to, or even dominate above the main MSP-layer, the total measured photoelectron current. Among the other instruments on board was a set of two photometers to study the O2 (b1Σg+−X3Σg
Technical Note: Comparison between a direct and the standard, indirect method for dissolved organic nitrogen determination in freshwater environments with high dissolved inorganic nitrogen concentrations
Authors: Graeber D. , Gelbrecht J. , Kronvang B. , Gücker B. , Pusch M. T. , Zwirnmann E.
Published: November 2012

Abstract. Research on dissolved organic nitrogen (DON) in aquatic systems with high dissolved inorganic nitrogen (DIN, the sum of NO3–, NO2– and NH4+) concentrations is often hampered by high uncertainties regarding the determined DON concentration. The reason is that DON is determined indirectly as the difference between total dissolved nitrogen (TDN) and DIN. In this standard approach to determine DON concentrations, even small relative measurement errors of the DIN and TDN concentrations propagate into high absolute errors of DON concentrations at high DIN : TDN ratios. To improve the DON measurement accuracy at high DIN : TDN ratios, we investigated the DON measurement accuracy of this standard approach according to the DIN : TDN ratio and compared it to the direct measurement of DON by size-exclusion chromatography (SEC) for freshwater systems. For this, we used standard compounds and natural samples with and without DIN enrichment. We show that for the standard approach, large errors of the determined DON concentrations at DIN : TDN ratios >0.6 occur for both standard compounds and natural samples. In contrast, measurements of DON by SEC always gave low errors at high DIN : TDN ratios due to the successful separation of DON from DIN. For SEC, DON recovery rates were 91–108% for five pure standard compounds and 89–103% for two standard compounds, enriched with DIN. Moreover, SEC resulted in 93–108% recovery rates for DON concentrations of natural samples at a DIN : TDN ratio of 0.8 and the technique was successfully applied to a range of samples from waste water treatment plants to forest and agricultural streams. With 2.5 h of measurement time per sample, SEC is slower, but more accurate than the standard approach for determination of DON concentrations in freshwaters with DIN : TDN ratios >0.6. To sum up, the direct DON measurement by SEC enables better understanding of the nitrogen cycle of urban and agricultural freshwater systems.
The effect of cattle slurry in combination with nitrate and the nitrification inhibitor dicyandiamide on in situ nitrous oxide and dinitrogen emissions
Authors: McGeough K. L. , Laughlin R. J. , Watson C. J. , Müller C. , Ernfors M. , Cahalan E. , Richards K. G.
Published: December 2012

Abstract. A field study was conducted to determine the effect of the nitrification inhibitor dicyandiamide (DCD) on N2O and N2 emissions after cattle slurry (CS) application in the presence of nitrate (NO3) fertiliser on seven different occasions (between March 2009 and March 2011). N2O emissions from CS in the presence of NO3 fertiliser were very high (0.4–8.7% of applied N) over a 20-day period, under mild moist conditions. Emissions were significantly larger from the CS treatment compared to an NH4+-N source, supplying the same rate of N as in the slurry. This study supports the view that organic fertilisers should not be applied at the same time as nitrate-based fertilisers, as significant increases in N2O emissions occur. The average N2O mole fraction (N2O/(N2O + N2)) over all seven application dates was 0.34 for CSNO3 compared to 0.24 for the NH4ClNO3 treatment, indicating the dominance of N2 emissions. The rate of nitrification in CSNO3 was slower than in NH4ClNO3, and DCD was found to be an effective nitrification inhibitor in both treatments. However, as N2O emissions were found to be predominantly associated with the NO3 pool, the effect of DCD in lowering N2O emissions is limited in the presence of a NO3 fertiliser. To obtain the maximum cost-benefit of DCD in lowering N2O emissions, under mild moist conditions, it should not be applied to a nitrate containing fertiliser (e.g. ammonium nitrate or calcium ammonium nitrate), and therefore the application of DCD should be restricted to ammonium-based organic or synthetic fertilisers.
Glacial-interglacial dynamics of Antarctic firn columns: comparison between simulations and ice core air-δ15N measurements
Authors: Capron E. , Landais A. , Buiron D. , Cauquoin A. , Chappellaz J. , Debret M. , Jouzel J. , Leuenberger M. , Martinerie P. , Masson-Delmotte V. , Mulvaney R. , Parrenin F. , Prié F.
Published: December 2012

Abstract. Correct estimate of the firn lock-in depth is essential for correctly linking gas and ice chronologies in ice cores studies. Here, two approaches to constrain the firn depth evolution in Antarctica are presented over the last deglaciation: output of a firn densification model and measurements of δ15N of N2 in air trapped in ice core. Since the firn densification process is largely governed by surface temperature and accumulation rate, we have investigated four ice cores drilled in coastal (Berkner Island, BI, and James Ross Island, JRI) and semi coastal (TALDICE and EPICA Dronning Maud Land, EDML) Antarctic regions. Combined with available δ15N measurements performed from the EPICA Dome C (EDC) site, the studied regions encompass a large range of surface accumulation rate and temperature conditions. While firn densification simulations are able to correctly represent most of the δ15N trends over the last deglaciation measured in the EDC, BI, TALDICE and EDML ice cores, they systematically fail to capture BI and EDML δ15N glacial levels, a mismatch previously seen for Central East Antarctic ice cores. Using empirical constraints of the EDML gas-ice depth offset during the Laschamp event (~ 41 ka), we can rule out the existence of a large convective zone as the explanation of the glacial firn model-δ15N data mismatch for this site. The good match between modelled and measured δ15N at TALDICE as well as the lack of any clear correlation between insoluble dust concentration in snow and δ15N records in the different ice cores suggest that past changes in loads of impurities are not the only main driver of glacial-interglacial changes in firn lock-in depth. We conclude that firn densification dynamics may instead be driven mostly by accumulation rate changes. The mismatch between modelled and measured δ15N may be due to inaccurate reconstruction of past accumulation rate or underestimated influence of accumulation rate in firnification models.
Future Flows Hydrology: an ensemble of daily river flow and monthly groundwater levels for use for climate change impact assessment across Great Britain
Authors: Prudhomme C. , Haxton T. , Crooks S. , Jackson C. , Barkwith A. , Williamson J. , Kelvin J. , Mackay J. , Wang L. , Young A. , Watts G.
Published: December 2012

Abstract. The dataset Future Flows Hydrology was developed as part of the project "Future Flows and Groundwater Levels" to provide a consistent set of transient daily river flow and monthly groundwater levels projections across England, Wales and Scotland to enable the investigation of the role of climate variability on river flow and groundwater levels nationally and how this may change in the future. Future Flows Hydrology is derived from Future Flows Climate, a national ensemble projection derived from the Hadley Centre's ensemble projection HadRM3-PPE to provide a consistent set of climate change projections for the whole of Great Britain at both space and time resolutions appropriate for hydrological applications. Three hydrological models and one groundwater level model were used to derive Future Flows Hydrology, with 30 river sites simulated by two hydrological models to enable assessment of hydrological modelling uncertainty in studying the impact of climate change on the hydrology. Future Flows Hydrology contains an 11-member ensemble of transient projections from January 1951 to December 2098, each associated with a single realisation from a different variant of HadRM3 and a single hydrological model. Daily river flows are provided for 281 river catchments and monthly groundwater levels at 24 boreholes as .csv files containing all 11 ensemble members. When separate simulations are done with two hydrological models, two separate .csv files are provided. Because of potential biases in the climate-hydrology modelling chain, catchment fact sheets are associated with each ensemble. These contain information on the uncertainty associated with the hydrological modelling when driven using observed climate and Future Flows Climate for a period representative of the reference time slice 1961–1990 as described by key hydrological statistics. Graphs of projected changes for selected hydrological indicators are also provided for the 2050s time slice. Limitations associated with the dataset are provided, along with practical recommendation of use. Future Flows Hydrology is freely available for non-commercial use under certain licensing conditions. For each study site, catchment averages of daily precipitation and monthly potential evapotranspiration, used to drive the hydrological models, are made available, so that hydrological modelling uncertainty under climate change conditions can be explored further. doi:10.5285/f3723162-4fed-4d9d-92c6-dd17412fa37b.
Observing desert dust devils with a pressure logger
Authors: Lorenz R. D.
Published: December 2012

Abstract. A commercial pressure logger has been adapted for long-term field use. Its flash memory affords the large data volume to allow months of pressure measurements to be acquired at the rapid cadence (>1 Hz) required to detect dust devils, small dust-laden convective vortices observed in arid regions. The power consumption of the unit is studied and battery and solar/battery options evaluated for long-term observations. A two-month long field test is described, and several example dust devil encounters are examined. In addition, a periodic (~20 min) convective signature is observed, and some lessons in operations and correction of data for temperature drift are reported. The unit shows promise for obtaining good statistics on dust devil pressure drops, to permit comparison with Mars lander measurements, and for array measurements.