bluuebunny/crossref_metadata_2025 huggingface dataset:
Structured Light Scanning to Evaluate Three-Dimensional Anthropometry in HIV Facial Lipoatrophy
Authors: Gacto-Sánchez Purificación , Lobo-Bailón Fernando , Suárez Cristina , Gómez- Cía Tomás
Published: November 2011

The psychological and social impact of the lipodystrophy syndrome on HIV-infected individuals may be quite considerable and adversely affect their quality of life. Currently no validated assessment tool for facial lipoatrophy is available. The main objective of this paper is to evaluate the reliability of interactive anthropometric landmark localization based on digitized 3D facial images. By comparing both computed tomography (CT) and structured light scanning we try to demonstrate that surface scanning shows a higher sensitivity in measuring facial reference points. Besides, we evaluate the reproducibility of facial 3D white-light scans. Three HIVpositive men attending our plastic surgery outpatient clinic for treatment of facial lipodystrophy were enrolled in the study. Localization of anthropometric landmarks measurements was performed on the patients. All patients underwent a facial CT and a facial white-light scanning on the same day. The inter-landmark distances measured on facial models developed from CT aided with VirSSPA 3D software and structured light scanning were compared to the real human models. We found that facial distances measured in the CT 3D reconstruction showed a mean error margin of 0.357 cm from the real distances measured on patients. On the contrary, mean error margin with the white-light scanning was of 0.096 cm. In both cases, measurements were found to be statistically significant (p < 0.05). When compared to CT reconstructions, white-light surface scanning offers a more accurate landmark localization as well as reliable reconstructions of up to less than the tenth of a millimetre as average when compared to real measurements on facial human models.
Geology of the Weldon Bay - Syme Lake area, Manitoba
Authors: Froese E
Published: November 2011

The Weldon Bay-Syme Lake area, located 40 km northeast of Flin Flon, Manitoba, straddles the boundary between the Flin Flon volcanic belt and the southern flank of the Kisseynew gneiss belt (Zwanzig et al., 1995; Zwanzig, 1999). The southern flank, in contrast to
the central region of the Kisseynew gneiss belt, includes considerable areas of volcanic rocks and these are currently regarded as an extension of the Flin Flon volcanic belt (H.V. Zwanzig, pers. comm., 2007).
Natural in utero infection of neonatal calves with bovine viral diarrhoea virus on a large dairy farm in Saudi Arabia
Authors: Abuelzein Eltayb M. , Al-Khaliyfa Mofeed A. , Gameel Ahmed A.
Published: November 2011

The dairy industry is a large and important business in Saudi Arabia. Although farms are administered to high international standards, some reproduction problems, of uncertain aetiology, are encountered. The most frequently seen are conception failures, abortions, stillbirths and the birth of weak or malformed calves. These conditions are suggestive of bovine viral diarrhoea virus (BVDV) infection. Unfortunately, very little published information is available regarding the impact of this disease on cattle populations in Saudi Arabia. As a consequence, the present study was carried out and is the first of its kind in Saudi Arabia and the Gulf region. The aim of the study was to elucidate the role of in utero BVDV infection leading to the birth of weak or malformed calves on a large dairy farm in Saudi Arabia. The study was divided into two parts. Firstly, apparently healthy neonatal calves were sampled for the detection of pre-colostral serum antibodies to BVDV. The presence of these antibodies indicates exposure of the foetus to BVDV during the last two trimesters of gestation. Secondly, tissue samples from malformed neonatal calves were examined for the presence of BVDV antigens. Detection of such antigens confirms exposure of the foetus to the virus during the first trimester of gestation. The results of the investigation indicated that 36.1% of the neonatal calves were exposed to BVDV infection in utero. This is higher than what has been reported in the literature and suggests that dairy farmers in the Arabian Peninsula need to be made aware of the dangers of BVDV infections in their herds. The epidemiological significance of the results is discussed.
�Within the enclave� � Profiling South African social and religious developments since 1994
Authors: Cilliers Johan , Nell Ian A.
Published: November 2011

The paper investigated religious and social transformations within a specific religious tradition in South Africa. After clarifying the charged concept of �transformation�, the authors showed that transformation is about more than changed systems and structures, for, on a deeper level, it is also about the change in relationships and attitudes between the different cultural groups in South Africa. The argument was supported by making use of data from the SA reconciliation barometer 2010 and the 2009 Transformation audit. In the next part of the paper, the authors took a closer look at the Dutch Reformed Church (DRC) as a case in point. The basic question they asked was how do these social transformations affect the religious transformations within the DRC and vice versa? By making use of Mary Douglas�s concept of �the enclave� it was proposed that a new enclave developed in the DRC after 1994, the characteristics of which were investigated in the remainder of the paper.
The Genetics of Pulmonary Arterial Hypertension in the Post‐BMPR2 Era
Authors: Fessel Joshua P. , Loyd James E. , Austin Eric D.
Published: November 2011

Pulmonary arterial hypertension (PAH) is a rapidly progressive and fatal disease for which there is an ever‐expanding body of genetic and related pathophysiological information on disease pathogenesis. The most common single culprit gene known is BMPR2, and animal models of the disease in several forms exist. There is a wealth of genetic data regarding modifiers of disease expression, penetrance, and severity. Despite the rapid accumulation of data in the last decade, a complete picture of the molecular pathogenesis of PAH leading to novel therapies is lacking. In this review, we attempt to summarize the current understanding of PAH from the genetic perspective. The most recent PAH demographics are discussed. Heritable PAH in the post‐BMPR2 era is examined in detail as the most robust model of PAH genetics in both animal models and human pedigrees. Important downstream molecular pathways and modifiers of disease expression are reviewed in light of what is known about PAH pathogenesis. Current and emerging therapies are examined in light of genetic data. The role of genetic testing in PAH in the post‐BMPR2 era is discussed. Finally, directions for future investigations that ideally will fulfill the promise of novel therapeutic or preventive strategies are discussed.
Surgical Treatment of Pulmonary Hypertension: Lung Transplantation
Authors: Long Jason , Russo Mark J. , Muller Charlie , Vigneswaran Wickii T.
Published: November 2011

Pulmonary hypertension (PH) is a serious and progressive disorder that results in right ventricular dysfunction that lead to subsequent right heart failure and death. When untreated the median survival for these patients is 2.8 years. Over the past decade advances in disease specific medical therapy considerably changed the natural history. This is reflected in a threefold decrease in the number of patients undergoing lung transplantation for PH which used to be main stay of treatment. Despite the successful development of medical therapy lung transplant still remains the gold standard for patients who fail medical therapy. Referral for lung transplant is recommended when patients have a less than 2‐3 years of predicted survival or in NYHA class III or IV. Both single and bilateral lung transplants have been successfully performed for PH but outcome analyses and survival comparisons generally favor a bilateral lung transplant.
Epigenetic Mechanisms of Pulmonary Hypertension
Authors: Kim Gene H. , Ryan John J. , Marsboom Glenn , Archer Stephen L.
Published: November 2011

Epigenetics refers to changes in phenotype and gene expression that occur without alterations in DNA sequence. Epigenetic modifications of the genome can be acquired de novo and are potentially heritable. This review focuses on the emerging recognition of a role for epigenetics in the development of pulmonary arterial hypertension (PAH). Lessons learned from the epigenetics in cancer and neurodevelopmental diseases, such as Prader‐Willi syndrome, can be applied to PAH. These syndromes suggest that there is substantial genetic and epigenetic cross‐talk such that a single phenotype can result from a genetic cause, an epigenetic cause, or a combined abnormality. There are three major mechanisms of epigenetic regulation, including methylation of CpG islands, mediated by DNA methyltransferases, modification of histone proteins, and microRNAs. There is substantial interaction between these epigenetic mechanisms. Recently, it was discovered that there may be an epigenetic component to PAH. In PAH there is downregulation of superoxide dismutase 2 (SOD2) and normoxic activation of hypoxia inducible factor (HIF‐1α). This decrease in SOD2 results from methylation of CpG islands in SOD2 by lung DNA methyltransferases. The partial silencing of SOD2 alters redox signaling, activates HIF‐1α) and leads to excessive cell proliferation. The same hyperproliferative epigenetic abnormality occurs in cancer. These epigenetic abnormalities can be therapeutically reversed. Epigenetic mechanisms may mediate gene‐environment interactions in PAH and explain the great variability in susceptibility to stimuli such as anorexigens, virus, and shunts. Epigenetics may be relevant to the female predisposition to PAH and the incomplete penetrance of BMPR2 mutations in familial PAH.
MicroRNAs‐Control of Essential Genes: Implications for Pulmonary Vascular Disease
Authors: Joshi Sachindra R. , McLendon Jared M. , Comer Brian S. , Gerthoffer William T.
Published: November 2011

During normal lung development and in lung diseases structural cells in the lungs adapt to permit changes in lung function. Fibroblasts, myofibroblasts, smooth muscle, epithelial cells, and various progenitor cells can all undergo phenotypic modulation. In the pulmonary vasculature occlusive vascular lesions that occur in severe pulmonary arterial hypertension are multifocal, polyclonal lesions containing cells presumed to have undergone phenotypic transition resulting in altered proliferation, cell lifespan or contractility. Dynamic changes in gene expression and protein composition that underlie processes responsible for such cellular plasticity are not fully defined. Advances in molecular biology have shown that multiple classes of ribonucleic acid (RNA) collaborate to establish the set of proteins expressed in a cell. Both coding Messenger Ribonucleic acid (mRNA) and small noncoding RNAs (miRNA) act via multiple parallel signaling pathways to regulate transcription, mRNA processing, mRNA stability, translation and possibly protein lifespan. Rapid progress has been made in describing dynamic features of miRNA expression and miRNA function in some vascular tissues. However posttranscriptional gene silencing by microRNA‐mediated mRNA degradation and translational blockade is not as well defined in the pulmonary vasculature. Recent progress in defining miRNAs that modulate vascular cell phenotypes is reviewed to illustrate both functional and therapeutic significance of small noncoding RNAs in pulmonary arterial hypertension.
Pulmonary Hemodynamic Responses to Inhaled NO in Chronic Heart Failure Depend on PDE5 G(‐1142)T Polymorphism
Authors: Damy Thibaud , Lesault Pierre‐François , Guendouz Soulef , Eddahibi Saadia , Tu Ly , Marcos Elisabeth , Guellich Aziz , Dubois‐Randé Jean‐Luc , Teiger Emmanuel , Hittinger Luc , Adnot Serge
Published: November 2011

To evaluate the vasoconstrictor component of PH in CHF by investigating the hemodynamic response to inhaled nitric oxide (iNO) and to determine whether this response was influenced by the phosphodiesterase 5 gene (PDE5) G(1142)T polymorphism. CHF patients underwent right heart catheterization at rest and after 20 ppm of iNO and plasma cGMP and PDE5 G(1142)T polymorphism determinations. Of the 72 included CHF patients (mean age, 53±1 years; mean left ventricular ejection fraction, 29±1%; and mean pulmonary artery pressure, 25.5±1.3 mmHg), 54% had ischemic heart disease. Proportions of patients with the TT, GT, and GG genotypes were 39%, 42% and 19% respectively. Baseline hemodynamic characteristics were not significantly different across PDE5 genotype groups, although pulmonary capillary wedge pressure (PCWP) tended to be lower in the TT group (P=0.09). Baseline plasma cGMP levels were significantly lower in the TT than in the GG and GT patients. With iNO, PVR diminished in TT (‐33%) but not GG (‐1.6%) or GT (0%) patients (P=0.002); and PCWP increased more in TT than in GT (P<0.05) or GG (P<0.003) patients. The PDE5 G(‐1142) polymorphism is therefore a major contributor to the iNO‐induced PVR decrease in CHF.
Idiopathic and Heritable PAH Perturb Common Molecular Pathways, Correlated with Increased MSX1 Expression
Authors: Austin Eric D. , Menon Swapna , Hemnes Anna R. , Robinson Linda R. , Talati Megha , Fox Kelly L. , Cogan Joy D. , Hamid Rizwan , Hedges Lora K. , Robbins Ivan , Lane Kirk , Newman John H. , Loyd James E. , West James
Published: November 2011

The majority of pulmonary arterial hypertension (PAH) is not associated with BMPR2 mutation, and major risk factors for idiopathic PAH are not known. The objective of this study was to identify a gene expression signature for IPAH. To accomplish this, we used Affymetrix arrays to probe expression levels in 86 patient samples, including 22 healthy controls, 20 IPAH patients, 20 heritable PAH patients (HPAH), and 24 BMPR2 mutation carriers that were as yet unaffected (UMC). Culturing the patient cells removes the signatures of drug effects and inflammation which have made interpretation of results from freshly isolated lymphocytes problematic. We found that gene expression signatures from IPAH patients clustered either with HPAH patients or in a single distinct group. There were no groups of genes changed in IPAH that were not also changed in HPAH. HPAH, IPAH, and UMC had common changes in metabolism, actin dynamics, adhesion, cytokines, metabolism, channels, differentiation, and transcription factors. Common to IPAH and HPAH but not UMC were an upregulation of vesicle trafficking, oxidative/nitrosative stress, and cell cycle genes. The transcription factor MSX1, which is known to regulate BMP signaling, was the most upregulated gene (4∗) in IPAH patients. These results suggest that IPAH cases have a shared molecular origin, which is closely related to, but distinct from, HPAH. HPAH and IPAH share the majority of altered signaling pathways, suggesting that treatments developed to target the molecular etiology of HPAH will also be effective against IPAH.
S1P4 Receptor Mediates S1P‐Induced Vasoconstriction in Normotensive and Hypertensive Rat Lungs
Authors: Ota Hiroki , Beutz Michelle A. , Ito Masako , Abe Kohtaro , Oka Masahiko , McMurtry Ivan F.
Published: November 2011

This study aimed to identify receptors mediating sphingosine‐1‐phosphate (S1P)‐induced vasoconstriction in the normotensive and chronic hypoxia‐induced hypertensive rat pulmonary circulation. In isolated perfused lungs from normoxic rats, infusion of S1P caused a sustained vasoconstriction, which was not reduced by combinational pretreatment with the dual S1P1 and 3 receptor antagonist VPC23019 and the S1P2 receptor antagonist JTE013. The S1P4 receptor agonists phytosphingosine‐1‐phospate and VPC23153, but not the dual S1P1 and 3 receptor agonist VPC24191, caused dose‐dependent vasoconstrictions. In hypertensive lungs from chronically hypoxic rats, the vasoconstrictor responses to S1P and VPC23153 were markedly enhanced. The S1P4 receptor agonist VPC 23153 caused contraction of isolated pulmonary but not of renal or mesenteric arteries from chronically hypoxic rats. S1P4 receptor protein as well as mRNA were detected in both normotensive and hypertensive pulmonary arteries. In contrast to what has been reported in the systemic circulation and mouse lung, our findings raise the possibility that S1P4 receptor plays a significant role in S1P‐induced vasoconstriction in the normotensive and hypertensive rat pulmonary circulation.
Neurogenic Responses in Rat and Porcine Large Pulmonary Arteries
Authors: Duggan Daniel J. , Bieger Detlef , Tabrizchi Reza
Published: November 2011

Pharmacological differences between neurogenic sympathetic responses in rat and pig isolated pulmonary arteries were examined in strip preparations. Electrical field stimulation in the range of 0.6 to 40 Hz resulted in frequency‐dependent contractions in terms of amplitude and rate of rise. Responses in the rat declined sharply from pulmonary trunk to main artery; in contrast, in the pig they continued into the third‐order vessels. Contractions were inhibited in the presence of tetrodotoxin, prazosin or WB‐4101 and hence neurogenic in origin. Cocaine enhanced field stimulated contractions in both rat and porcine tissues; however, the effect in the former was of significantly greater magnitude in terms of either area under the mechanogram or height of contraction. In addition, the rate of rise, time to peak and duration of peak were all increased in the rat but less so or not in the pig. Field stimulated contractions were virtually abolished by guanethidine (1×10−6 M) in rat but not in porcine pulmonary arteries in which a ten‐fold higher concentration significantly reduced neurogenic contractions and abolished them in 2 out of 4 tissues tested. The effect of guanethidine (1×10−6 M) observed in blood vessels of rat exceeded about five‐fold that observed in porcine tissues. Thus, neurogenic responses appear to be entirely mediated by extra‐junctional α1‐adrenoceptors in both species, and in contrast to the rat, pig tissues seem to have a noradrenaline re‐uptake that is either less efficient or operating near saturation.
Isolated Large Vessel Pulmonary Vasculitis as a Cause of Chronic Obstruction of the Pulmonary Arteries
Authors: Hagan Guy , Gopalan Deepa , Church Colin , Rassl Doris , Mukhtyar Chetan , Wistow Trevor , Lang Chim , Sivasothy Pasupathy , Stewart Susan , Jayne David , Sheares Karen , Tsui Steven , Jenkins David P. , Pepke‐Zaba Joanna
Published: November 2011

Isolated pulmonary artery involvement by large vessel vasculitis is rare. This case report describes two patients with large vessel pulmonary vasculitis initially thought to have chronic thromboembolic pulmonary hypertension who had their diagnosis revised following pulmonary endarterectomy surgery. Advances in imaging techniques such as positron emission tomography and magnetic resonance imaging have permitted complementary radiological methods of diagnosis and follow up of large vessel disease and these are discussed in conjunction with the immunosuppressive and operative management of these patients.
Pulmonary Hydatid Cyst with Complicating Aspergillus Infection Presenting as a Refractory Lung Abscess
Authors: Mahmood Nader , Azam Hamad , Ali M. Imran , Khan M. Anees
Published: November 2011

Background

Hydatid disease is rare in the United States. Rarely the hydatid cyst can become infected with mycotic organisms, such as Aspergillus. We describe a young male who presents with clinical features of suppurative lung abscess whose workup diagnosed hydatid cyst complicated by Aspergillus co-infection.

Case presentation

A 27-year-old Peruvian male was hospitalized because of fever, chills, and productive cough of three months’ duration. Clinical features were consistent with a suppurative lung abscess. Significant findings included leukocytosis with eosinophilia and a chest x-ray showing a large lingular lobe thick walled cavity with a wavy irregular fluid level. The patient ultimately underwent surgical resection of the lingular lobe. Examination of the surgical specimen revealed the cavity to be a hydatid cyst. Histologic examination of the cyst wall showed intense inflammation and several septate hyphae of Aspergillus species. The patient recovered fully and has remained in good health.

Conclusion

A thick-walled cavity and a wavy meniscus constitute unusual features for an ordinary pyogenic lung abscess and suggests other possibilities. Endogenous cases of hydatid disease are uncommon in the United States, with the majority of cases occurring in immigrants. There are few published case reports describing incidental findings of Aspergillus in a hydatid cyst. The rare occurrence of such a condition can lead to a delay in diagnosis and treatment.
Electronic Health Record Adoption – Maybe It’s not about the Money
Authors: Skinner A. , Windle J. , Grabenbauer L.
Published: November 2011

Objective: The slow adoption of electronic health record (EHR) systems has been linked to physician resistance to change and the expense of EHR adoption. This qualitative study was conducted to evaluate benefits, and clarify limitations of two mature, robust, comprehensive EHR Systems by tech-savvy physicians where resistance and expense are not at issue.

Methods: Two EHR systems were examined – the paperless VistA / Computerized Patient Record System used at the Veterans‘ Administration, and the General Electric Centricity Enterprise system used at an academic medical center. A series of interviews was conducted with 20 EHR-savvy multi-institutional internal medicine (IM) faculty and house staff. Grounded theory was used to analyze the transcribed data and build themes. The relevance and importance of themes were constructed by examining their frequency, convergence, and intensity.

Results: Despite eliminating resistance to both adoption and technology as drivers of acceptance, these two robust EHR’s are still viewed as having an adverse impact on two aspects of patient care, physician workflow and team communication. Both EHR’s had perceived strengths but also significant limitations and neither were able to satisfactorily address all of the physicians’ needs.

Conclusion: Difficulties related to physician acceptance reflect real concerns about EHR impact on patient care. Physicians are optimistic about the future benefits of EHR systems, but are frustrated with the non-intuitive interfaces and cumbersome data searches of existing EHRs.
Volatility of secondary organic aerosol during OH radical induced ageing
Authors: Salo K. , Hallquist M. , Jonsson Å. M. , Saathoff H. , Naumann K.-H. , Spindler C. , Tillmann R. , Fuchs H. , Bohn B. , Rubach F. , Mentel Th. F. , Müller L. , Reinnig M. , Hoffmann T. , Donahue N. M.
Published: November 2011

Abstract. The aim of this study was to investigate oxidation of SOA formed from ozonolysis of α-pinene and limonene by hydroxyl radicals. This paper focuses on changes of particle volatility, using a Volatility Tandem DMA (VTDMA) set-up, in order to explain and elucidate the mechanism behind atmospheric ageing of the organic aerosol. The experiments were conducted at the AIDA chamber facility of Karlsruhe Institute of Technology (KIT) in Karlsruhe and at the SAPHIR chamber of Forchungzentrum Jülich (FZJ) in Jülich. A fresh SOA was produced from ozonolysis of α-pinene or limonene and then aged by enhanced OH exposure. As an OH radical source in the AIDA-chamber the ozonolysis of tetramethylethylene (TME) was used while in the SAPHIR-chamber the OH was produced by natural light photochemistry. A general feature is that SOA produced from ozonolysis of α-pinene and limonene initially was rather volatile and becomes less volatile with time in the ozonolysis part of the experiment. Inducing OH chemistry or adding a new portion of precursors made the SOA more volatile due to addition of new semi-volatile material to the aged aerosol. The effect of OH chemistry was less pronounced in high concentration and low temperature experiments when lower relative amounts of semi-volatile material were available in the gas phase. Conclusions drawn from the changes in volatility were confirmed by comparison with the measured and modelled chemical composition of the aerosol phase. Three quantified products from the α-pinene oxidation; pinonic acid, pinic acid and methylbutanetricarboxylic acid (MBTCA) were used to probe the processes influencing aerosol volatility. A major conclusion from the work is that the OH induced ageing can be attributed to gas phase oxidation of products produced in the primary SOA formation process and that there was no indication on significant bulk or surface reactions. The presented results, thus, strongly emphasise the importance of gas phase oxidation of semi- or intermediate-volatile organic compounds (SVOC and IVOC) for atmospheric aerosol ageing.
Secondary organic aerosol formation in cloud droplets and aqueous particles (aqSOA): a review of laboratory, field and model studies
Authors: Ervens B. , Turpin B. J. , Weber R. J.
Published: November 2011

Abstract. Progress has been made over the past decade in predicting secondary organic aerosol (SOA) mass in the atmosphere using vapor pressure-driven partitioning, which implies that SOA compounds are formed in the gas phase and then partition to an organic phase (gasSOA). However, discrepancies in predicting organic aerosol oxidation state, size and product (molecular mass) distribution, relative humidity (RH) dependence, color, and vertical profile suggest that additional SOA sources and aging processes may be important. The formation of SOA in cloud and aerosol water (aqSOA) is not considered in these models even though water is an abundant medium for atmospheric chemistry and such chemistry can form dicarboxylic acids and "humic-like substances" (oligomers, high-molecular-weight compounds), i.e. compounds that do not have any gas phase sources but comprise a significant fraction of the total SOA mass. There is direct evidence from field observations and laboratory studies that organic aerosol is formed in cloud and aerosol water, contributing substantial mass to the droplet mode. This review summarizes the current knowledge on aqueous phase organic reactions and combines evidence that points to a significant role of aqSOA formation in the atmosphere. Model studies are discussed that explore the importance of aqSOA formation and suggestions for model improvements are made based on the comprehensive set of laboratory data presented here. A first comparison is made between aqSOA and gasSOA yields and mass predictions for selected conditions. These simulations suggest that aqSOA might contribute almost as much mass as gasSOA to the SOA budget, with highest contributions from biogenic emissions of volatile organic compounds (VOC) in the presence of anthropogenic pollutants (i.e. NOx) at high relative humidity and cloudiness. Gaps in the current understanding of aqSOA processes are discussed and further studies (laboratory, field, model) are outlined to complement current data sets.
Observations of nonmethane organic compounds during ARCTAS − Part 1: Biomass burning emissions and plume enhancements
Authors: Hornbrook R. S. , Blake D. R. , Diskin G. S. , Fried A. , Fuelberg H. E. , Meinardi S. , Mikoviny T. , Richter D. , Sachse G. W. , Vay S. A. , Walega J. , Weibring P. , Weinheimer A. J. , Wiedinmyer C. , Wisthaler A. , Hills A. , Riemer D. D. , Apel E. C.
Published: November 2011

Abstract. Mixing ratios of a large number of nonmethane organic compounds (NMOCs) were observed by the Trace Organic Gas Analyzer (TOGA) on board the NASA DC-8 as part of the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) field campaign. Many of these NMOCs were observed concurrently by one or both of two other NMOC measurement techniques on board the DC-8: proton-transfer-reaction mass spectrometry (PTR-MS) and whole air canister sampling (WAS). A comparison of these measurements to the data from TOGA indicates good agreement for the majority of co-measured NMOCs. The ARCTAS study, which included both spring and summer deployments, provided opportunities to sample a large number of biomass burning (BB) plumes with origins in Asia, California and central Canada, ranging from very recent emissions to plumes aged one week or more. For this analysis, BB smoke interceptions were grouped by flight, source region and, in some cases, time of day, generating 40 identified BB plumes for analysis. Normalized excess mixing ratios (NEMRs) to CO were determined for each of the 40 plumes for up to 19 different NMOCs or NMOC groups. Although the majority of observed NEMRs for individual NMOCs or NMOC groups were in agreement with previously-reported values, the observed NEMRs to CO for ethanol, a rarely quantified gas-phase trace gas, ranged from values similar to those previously reported, to up to an order of magnitude greater. Notably, though variable between plumes, observed NEMRs of individual light alkanes are highly correlated within BB emissions, independent of estimated plume ages. BB emissions of oxygenated NMOC were also found to be often well-correlated. Using the NCAR Master Mechanism chemical box model initialized with concentrations based on two observed scenarios, fresh Canadian BB and fresh Californian BB, decreases are predicted for the low molecular weight carbonyls (i.e. formaldehyde, acetaldehyde, acetone and methyl ethyl ketone, MEK) and alcohols (i.e. methanol and ethanol) as the plumes evolve in time, i.e. the production of these compounds is less than the chemical loss. Comparisons of the modeled NEMRs to the observed NEMRs from BB plumes estimated to be three days in age or less indicate overall good agreement.
Experimental study of the role of physicochemical surface processing on the IN ability of mineral dust particles
Authors: Niedermeier D. , Hartmann S. , Clauss T. , Wex H. , Kiselev A. , Sullivan R. C. , DeMott P. J. , Petters M. D. , Reitz P. , Schneider J. , Mikhailov E. , Sierau B. , Stetzer O. , Reimann B. , Bundke U. , Shaw R. A. , Buchholz A. , Mentel T. F. , Stratmann F.
Published: November 2011

Abstract. During the measurement campaign FROST 2 (FReezing Of duST 2), the Leipzig Aerosol Cloud Interaction Simulator (LACIS) was used to investigate the influence of various surface modifications on the ice nucleating ability of Arizona Test Dust (ATD) particles in the immersion freezing mode. The dust particles were exposed to sulfuric acid vapor, to water vapor with and without the addition of ammonia gas, and heat using a thermodenuder operating at 250 °C. Size selected, quasi monodisperse particles with a mobility diameter of 300 nm were fed into LACIS and droplets grew on these particles such that each droplet contained a single particle. Temperature dependent frozen fractions of these droplets were determined in a temperature range between −40 °C ≤T≤−28 °C. The pure ATD particles nucleated ice over a broad temperature range with their freezing behavior being separated into two freezing branches characterized through different slopes in the frozen fraction vs. temperature curves. Coating the ATD particles with sulfuric acid resulted in the particles' IN potential significantly decreasing in the first freezing branch (T>−35 °C) and a slight increase in the second branch (T≤−35 °C). The addition of water vapor after the sulfuric acid coating caused the disappearance of the first freezing branch and a strong reduction of the IN ability in the second freezing branch. The presence of ammonia gas during water vapor exposure had a negligible effect on the particles' IN ability compared to the effect of water vapor. Heating in the thermodenuder led to a decreased IN ability of the sulfuric acid coated particles for both branches but the additional heat did not or only slightly change the IN ability of the pure ATD and the water vapor exposed sulfuric acid coated particles. In other words, the combination of both sulfuric acid and water vapor being present is a main cause for the ice active surface features of the ATD particles being destroyed. A possible explanation could be the chemical transformation of ice active metal silicates to metal sulfates. The strongly enhanced reaction between sulfuric acid and dust in the presence of water vapor and the resulting significant reductions in IN potential are of importance for atmospheric ice cloud formation. Our findings suggest that the IN concentration can decrease by up to one order of magnitude for the conditions investigated.
Atmospheric dust modeling from meso to global scales with the online NMMB/BSC-Dust model – Part 2: Experimental campaigns in Northern Africa
Authors: Haustein K. , Pérez C. , Baldasano J. M. , Jorba O. , Basart S. , Miller R. L. , Janjic Z. , Black T. , Nickovic S. , Todd M. C. , Washington R.
Published: November 2011

Abstract. The new online NMMB/BSC-Dust model is intended to provide short to medium-range weather and dust forecasts from regional to global scales. The companion paper Pérez et al., 2011 develops the dust model parameterizations and provides daily to annual evaluations of the model for its global and regional configurations. Modeled aerosol optical depth (AOD) was evaluated against AERONET Sun photometers over Northern Africa, Middle East and Europe with correlations around 0.6–0.7 on average without dust data assimilation. In this paper we analyze in detail the behavior of the model using data from the Saharan Mineral dUst experiment (SAMUM-1) in 2006 and the Bodélé Dust Experiment (BoDEx) in 2005. AOD from satellites and Sun photometers, vertically resolved extinction coefficients from lidars and particle size distributions at the ground and in the troposphere are used, complemented by wind profile data and surface meteorological measurements. All simulations were performed at the regional scale for the Northern African domain at the expected operational resolution of 25 km. Model results for SAMUM-1 generally show good agreement with satellite data over the most active Saharan dust sources. The model reproduces the AOD from Sun photometers close to sources and after long-range transport, and the dust size spectra at different height levels. At this resolution, the model is not able to reproduce a large haboob occurred during the campaign. Some deficiencies are found concerning the vertical distribution. The mixing height is underestimated which may be attributed to poor soil initial conditions. For the BoDEx period, particular attention is paid to understand the dust model behavior in relation with the low level jet (LLJ) in the Bodélé. The diurnal temperature cycle depends strongly on the soil moisture, which is underestimated in the NCEP analysis used for model initialization. The daily maximum surface wind speeds are underestimated up to 50% in some days even when using a more accurate soil moisture initialization. The dust plume over the Bodélé is well reproduced by the model and the reductions in the threshold friction velocity substantially reduce the negative AOD bias in the model due to wind speed underestimation. The LLJ is also well reproduced, which is remarkable given the rather poor model initialization with NCEP-FNL data.
Lower hybrid resonances stimulated by the four CLUSTER relaxation sounders deep inside the plasmasphere: observations and inferred plasma characteristics
Authors: Kougblénou S. , Lointier G. , Décréau P. M. E. , Trotignon J.-G. , Rauch J.-L. , Vallières X. , Canu P. , Masson A. , Pickett J.
Published: November 2011

Abstract. The frequency range of the WHISPER relaxation sounder instrument on board CLUSTER, 4–80 kHz, has been chosen so as to encompass the electron gyro-frequency, Fce, and the electron plasma frequency, Fp, in most regions to be explored. Measurement of those frequencies, which are triggered as resonances by the sounder, provides a direct estimation of in situ fundamental plasma characteristics: electron density and magnetic field intensity. In the late mission phase, CLUSTER penetrated regions deep inside the plasmasphere where Fce and Fp are much higher than the upper frequency of the sounder's range. However, they are of the right order of magnitude as to place the lower hybrid frequency, Flh, in the 4–15 kHz band. This characteristic frequency, placed at a resonance of the medium, is triggered by the sounder's transmitter and shows up as an isolated peak in the received spectrum, not present in spectra of naturally occuring VLF waves. This paper illustrates, from analysis of case events, how measured Flh values give access to a plasma diagnostic novel of its kind. CLUSTER, travelling along its orbit, encounters favourable conditions where Fce is increasing and Fp decreasing, such that Fce/Fp increases from values below unity to values above unity. Measured Flh values thus give access, in turn, to the effective mass, Meff, indicative of plasma ion composition, and to the core plasmasphere electron density value, a parameter difficult to measure. The analysed case events indicate that the estimated quantities (Meff in the 1.0–1.4 range, Ne in the 5 × 102–104 cm−3 range) are varying with external factors (altitude, L value, geomagnetic activity) in a plausible way. Although covering only a restricted region (mid-latitude, low altitude inner plasmasphere), these measurements are available, since late 2009, for all CLUSTER perigee passes not affected by eclipses (on average, roughly a third of a total of ~200 passes per year) and offer multipoint observations previously unavailable in this region.
Simulation of anthropogenic CO2 uptake in the CCSM3.1 ocean circulation-biogeochemical model: comparison with data-based estimates
Authors: Wang S. , Moore J. K. , Primeau F. W. , Khatiwala S.
Published: November 2011

Abstract. The global ocean has taken up a large fraction of the CO2 released by human activities since the industrial revolution. Quantifying the oceanic anthropogenic carbon (Cant) inventory and its variability is important for predicting the future global carbon cycle. The detailed comparison of data-based and model-based estimates is essential for the validation and continued improvement of our prediction capabilities. So far, three global estimates of oceanic Cant inventory that are "data-based" and independent of global ocean circulation models have been produced: one based on the ΔC* method, and two are based on reconstructions of the Green function for the surface-to-interior transport, the TTD method and the maximum entropy inversion method (KPH). The KPH method, in particular, is capable of reconstructing the history of Cant inventory through the industrial era. In the present study we use forward model simulations of the Community Climate System Model (CCSM3.1) to estimate the Cant inventory and compare the results with the data-based estimates. We also use the simulations to test several assumptions of the KPH method, including the assumption of constant climate and circulation, which is common to all the data-based estimates. Though the integrated estimates of global Cant inventories are consistent with each other, the regional estimates show discrepancies up to 50 %. The CCSM3 model underestimates the total Cant inventory, in part due to weak mixing and ventilation in the North Atlantic and Southern Ocean. Analyses of different simulation results suggest that key assumptions about ocean circulation and air-sea disequilibrium in the KPH method are generally valid on the global scale, but may introduce significant errors in Cant estimates on regional scales. The KPH method should also be used with caution when predicting future oceanic anthropogenic carbon uptake.
Multiple-factor controls on terrestrial N2O flux over North America from 1979 through 2010
Authors: Xu X. F. , Tian H. Q. , Liu M. L. , Ren W. , Chen G. S. , Lu C. Q. , Zhang C.
Published: November 2011

Abstract. Nitrous oxide (N2O) is a potent greenhouse gas which also contributes to the depletion of stratospheric ozone (O3). However, the magnitude and underlying mechanisms for the spatiotemporal variations in the terrestrial sources of N2O are still far from certain. Using a process-based ecosystem model (DLEM – the Dynamic Land Ecosystem Model) driven by multiple global change factors, including climate variability, nitrogen (N) deposition, rising atmospheric CO2, trophospheric O3 pollution, N fertilizer application, and land conversion, the spatial and temporal variations in terrestrial N2O flux over North America were examined and attributed to various driving factors. From 1979 to 2010, the North America accumulatively emitted 55.1 ± 0.8 Tg N2O-N (1 Tg = 1012 g), of which global change factors contributed 2.8 ± 1.0 Tg N2O-N, and baseline emission contributed 52.3 ± 0.6 Tg N2O-N. Climate variability, N deposition, O3 pollution, N fertilizer application, and land conversion increased N2O emission by 0.3 ± 0.7 Tg N2O-N, 0.5 ± 0.1 Tg N2O-N, 0.11 ± 0.02 Tg N2O-N, 1.2 ± 0.1 Tg N2O-N, and 0.2 ± 0.02 Tg N2O-N, respectively. The elevated atmospheric CO2 led to a decrease in terrestrial N2O emission by 0.5 ± 0.07 Tg N2O-N. The interactive effect among multiple factors enhanced N2O emission by 0.9 ± 0.3 Tg N2O-N over the 32 years. At country level, climate variability and elevated atmospheric CO2 decreased, while all other single factors and multiple-factor interaction enhanced N2O emission in the United States of America (USA) over the study period. During the same time period, elevated atmospheric CO2 and multiple-factor interaction decreased, while other factors enhanced N2O emission from Canada. Elevated atmospheric CO2 and land conversion decreased while other factors enhanced N2O emission from Mexico. The interactive effects among climate variables play a predominant role in controlling climate -induced changes in N2O emission at both continental and country levels. Central and southeastern parts of the North America – including central Canada, central USA, southeastern USA, and all of Mexico – experienced increases in N2O emission from 1979 to 2010. The effects of climate variability and multiple-factor interaction dominating the inter-annual variations in terrestrial N2O emission at both continental and country levels indicate that projected changes in the global climate system during this century may substantially alter the regime of N2O emission from terrestrial ecosystems. They also imply that the interactive effect among global change factors may significantly affect N2O flux, needing more investigations through field experiments.
Using synoptic type analysis to understand New Zealand climate during the Mid-Holocene
Authors: Ackerley D. , Lorrey A. , Renwick J. A. , Phipps S. J. , Wagner S. , Dean S. , Singarayer J. , Valdes P. , Abe-Ouchi A. , Ohgaito R. , Jones J. M.
Published: November 2011

Abstract. Diagnosing the climate of New Zealand from low-resolution General Circulation Models (GCMs) is notoriously difficult due to the interaction of the complex topography and the Southern Hemisphere (SH) mid-latitude westerly winds. Therefore, methods of downscaling synoptic scale model data for New Zealand are useful to help understand past climate. New Zealand also has a wealth of palaeoclimate-proxy data to which the downscaled model output can be compared, and to provide a qualitative method of assessing the capability of GCMs to represent, in this case, the climate 6000 yr ago in the Mid-Holocene. In this paper, a synoptic weather and climate regime classification system using Empirical Orthogonal Function (EOF) analysis of GCM and reanalysis data was used. The climate regimes are associated with surface air temperature and precipitation anomalies over New Zealand. From the analysis in this study, we find at 6000 BP that increased trough activity in summer and autumn led to increased precipitation, with an increased north-south pressure gradient ("zonal events") in winter and spring leading to drier conditions. Opposing effects of increased (decreased) temperature are also seen in spring (autumn) in the South Island, which are associated with the increased zonal (trough) events; however, the circulation induced changes in temperature are likely to have been of secondary importance to the insolation induced changes. Evidence from the palaeoclimate-proxy data suggests that the Mid-Holocene was characterized by increased westerly wind events in New Zealand, which agrees with the preference for trough and zonal regimes in the models.
Online Optical Coherence Tomography during Subthreshold Laser Irradiation
Authors: Veritti Daniele , Sarao Valentina , Lanzetta Paolo
Published: November 2011

Purpose

To investigate the role of real-time optical coherence tomography (OCT) in the detection of standard and nonvisible subthreshold laser irradiation.

Methods

We used an integrated platform consisting of a slit-lamp, a digital camera, a slit-lamp mounted OCT, and a 532-nm laser photocoagulator (Topcon Inc., Tokyo, Japan). The laser aiming beam and the OCT scan were aligned to obtain real-time tomographic imaging of the irradiated area during laser exposure. Standard and subthreshold laser irradiation and simultaneous OCT acquisition were tested in artificial and biological samples. Laser testing cards were chosen as artificial samples. Freshly enucleated pig eyes were used for iris irradiation.

Results

Ophthalmoscopically visible reference burns were placed on the laser testing card in 2 parallel lines. Then, a series of laser spots with the same size and duration but different power were placed between the reference burns. Online OCT during laser irradiation detected changes in the reflectivity profile of the artificial sample at a power of 200 mW, in absence of ophthalmoscopically visible lesions. Similarly, reference burns were placed on pig iris and between them various laser spots were performed at ranging powers. Changes in the iris optical properties, as detected with online OCT, were produced with a power of 860 mW in absence of visible endpoint.

Conclusions

Online OCT is able to identify non-ophthalmoscopically visible lesions during subthreshold laser irradiation either in artificial samples or in pig iris.
Reversal of Sensation of Conjunctival Autograft after Pterygium Surgery
Authors: Sakarya Yasar , Sakarya Rabia , Kara Selcuk
Published: November 2011

Purpose

To evaluate sensation change at nasal and superior conjunctival and corneal quadrants after pterygium surgery with conjunctival autograft.

Methods

A prospective study was carried out in 14 patients. Seventeen eyes were operated for primary nasal pterygium. Sensation in nasal and superior conjunctival and corneal quadrants was measured with a Cochet-Bonnet aesthesiometer (CBA) before, and at 2 weeks, 1 month, and every month for 6 months after surgery. Preoperative and postoperative measurements were recorded and analyzed with Wilcoxon signed-rank test.

Results

The mean patient age was 53.5 years (range 44-68). All patients had nasal primary pterygium and completed the 6-month follow-up. The conjunctival autograft was correctly positioned and fixed in all eyes with fibrin glue. Mean ± SD sensations in conjunctival autograft were none (p<0.05) at 1 month, 4.28±5.34 mm (p<0.05) at 2 months, 12.85±2.67 mm (p<0.05) at 3 months, and returned to normal level, 23.57±2.43 mm (p>0.05), at 4 months. Mean sensations in superior conjunctival area where the autograft was harvested were 11.42±5.56 mm (p<0.05) at 1 month, and returned to normal level, 22.14±2.67 mm (p>0.05), at 2 months. Mean sensations in nasal corneal area after surgery were 7.81±4.06 mm (p<0.05) at 2 weeks, 26.42±2.43 mm (p<0.05) at 1 month, and returned to normal level, 49.00±3.38 mm (p>0.05), at 2 months. Mean sensations in superior corneal area did not change postoperatively.

Conclusions

Anesthesia at first month and hypoesthesia at second and third month at conjunctival autograft was observed after pterygium surgery. Additionally, hypoesthesia was observed at nasal cornea and superior bulbar conjunctiva at the first month.