bluuebunny/crossref_metadata_2025 huggingface dataset:
Hemocyte quantitative changes in Anticarsia gemmatalis (Lepidoptera: Noctuidae) larvae infected by AgMNPV
Authors: Andrade Fábio Goulart de , Negreiro Maria Cláudia Cordeiro de , Levy Sheila Michele , Fonseca Inês Cristina de Batista , Moscardi Flávio , Falleiros Ângela Maria Ferreira
Published: May 2010

The initial effects of the infection by AgMNPV in the total and differential counts of the hemocytes in Anticarsia gemmatalis (Lepidoptera: Noctuidae) larvae were studied. The total number of the hemocytes did not decrease in infected larvae, as it occurred in non infected larvae. In infected larvae, the hemocyte types showed the following frequencies: plasmatocytes - 47.8%, esferulocytes - 25.9%, granulocytes - 15.8%, oenocytoids - 7.2%, prohemocytes - 2.8%, vermicytes - 0,5%. Only the percentage of the granulocytes was different among infected and non infected larvae, indicating that these cells responded quickly to the initial viral infection. These results showed the effective role of the hemocytes in the response of the A. gemmatalis to the infection by AgMNPV. The comprehension of the immunological mechanisms of this insect is an important tool to understand its biological control.
N-Glycosylation of Carnosinase Influences Protein Secretion and Enzyme Activity
Authors: Riedl Eva , Koeppel Hannes , Pfister Frederick , Peters Verena , Sauerhoefer Sibylle , Sternik Paula , Brinkkoetter Paul , Zentgraf Hanswalter , Navis Gerjan , Henning Robert H. , Van Den Born Jacob , Bakker Stephan J.L. , Janssen Bart , van der Woude Fokko J. , Yard Benito A.
Published: May 2010

OBJECTIVE

The (CTG)n polymorphism in the serum carnosinase (CN-1) gene affects CN-1 secretion. Since CN-1 is heavily glycosylated and glycosylation might influence protein secretion as well, we tested the role of N-glycosylation for CN-1 secretion and enzyme activity. We also tested whether CN-1 secretion is changed under hyperglycemic conditions.

RESULTS

N-glycosylation of CN-1 was either inhibited by tunicamycin in pCSII-CN-1–transfected Cos-7 cells or by stepwise deletion of its three putative N-glycosylation sites. CN-1 protein expression, N-glycosylation, and enzyme activity were assessed in cell extracts and supernatants. The influence of hyperglycemia on CN-1 enzyme activity in human serum was tested in homozygous (CTG)5 diabetic patients and healthy control subjects.

Tunicamycin completely inhibited CN-1 secretion. Deletion of all N-glycosylation sites was required to reduce CN-1 secretion efficiency. Enzyme activity was already diminished when two sites were deleted. In pCSII-CN-1–transfected Cos-7 cells cultured in medium containing 25 mmol/l d-glucose, the immature 61 kilodaltons (kDa) CN-1 immune reactive band was not detected. This was paralleled by an increased GlcNAc expression in cell lysates and CN-1 expression in the supernatants. Homozygous (CTG)5 diabetic patients had significantly higher serum CN-1 activity compared with genotype-matched, healthy control subjects.

CONCLUSIONS

We conclude that apart from the (CTG)n polymorphism in the signal peptide of CN-1, N-glycosylation is essential for appropriate secretion and enzyme activity. Since hyperglycemia enhances CN-1 secretion and enzyme activity, our data suggest that poor blood glucose control in diabetic patients might result in an increased CN-1 secretion even in the presence of the (CTG)5 allele.
Replication Study for the Association Between Four Loci Identified by a Genome-Wide Association Study on European American Subjects With Type 1 Diabetes and Susceptibility to Diabetic Nephropathy in Japanese Subjects With Type 2 Diabetes
Authors: Maeda Shiro , Araki Shin-ichi , Babazono Tetsuya , Toyoda Masao , Umezono Tomoya , Kawai Koichi , Imanishi Masahito , Uzu Takashi , Watada Hirotaka , Suzuki Daisuke , Kashiwagi Atsunori , Iwamoto Yasuhiko , Kaku Kohei , Kawamori Ryuzo , Nakamura Yusuke
Published: May 2010

OBJECTIVE

Genetic factors are believed to contribute to the development and progression of diabetic nephropathy. Recently, a genome-wide association study for diabetic nephropathy revealed four novel candidate loci in European American subjects with type 1 diabetes. In this study, we determined the association of the four loci with diabetic nephropathy in Japanese subjects with type 2 diabetes.

RESEARCH DESIGN AND METHODS

We genotyped 11 singlenucleotide polymorphisms (SNPs) in four distinct loci (rs39059 and rs39075 in the CPVL/CHN2, rs1888747 and rs10868025 in FRMD3, rs739401 and rs451041 in CARS, and rs1041466, rs1411766, rs6492208, rs7989848, and rs9521445 in a chromosome 13q locus) in four independent Japanese populations.

RESULTS

Six SNPs were nominally associated with diabetic nephropathy in one of the four Japanese populations (P < 0.05; rs451041 in study 1; rs39059 and rs1888747 in study 3; rs1411766 in studies 1 and 4; and rs7989848 and rs9521445 in study 4); however, no significant association was observed for any SNP after correction for multiple testing errors in the individual populations. Nevertheless, a meta-analysis performed for the data obtained from all four populations revealed that one SNP (rs1411766) in chromosome 13q was significantly associated with diabetic nephropathy in the Japanese populations (nominal P = 0.004, corrected P = 0.04, odds ratio 1.26 [95% CI = 1.07–1.47]).

CONCLUSIONS

Our results suggest that the rs1411766 locus may be commonly involved in conferring susceptibility to diabetic nephropathy among subjects with type 1 or type 2 diabetes across different ethnic groups.
Weight Loss, Glycemic Control, and Changes in Cardiovascular Biomarkers in Patients With Type 2 Diabetes Receiving Incretin Therapies or Insulin in a Large Cohort Database
Authors: Horton Edward S. , Silberman Cheryl , Davis Keith L. , Berria Rachele
Published: May 2010

OBJECTIVE

Weight loss in patients with type 2 diabetes can improve glycemic control, lower blood pressure, and improve dyslipidemia. Glucagon-like peptide (GLP-1) receptor agonists are associated with weight loss and have potentially beneficial effects on cardiovascular risk biomarkers; however, there is limited information to indicate whether these effects remain outside of clinical trials.

RESEARCH DESIGN AND METHODS

Medical records from the General Electric Centricity research database were analyzed retrospectively to evaluate the relationship between weight loss and glycemic control and changes in blood pressure and lipids in patients with type 2 diabetes initiating therapy with exenatide, sitagliptin, or insulin. Baseline and follow-up (90–365 days after the index date) for weight, A1C, fasting blood glucose (FBG), blood pressure, triglycerides, and LDL, HDL, and total cholesterol were assessed.

RESULTS

A total of 6,280, 5,861, and 32,398 patients receiving exenatide, sitagliptin, or insulin, respectively, were included in the analysis. Exenatide-treated patients lost a mean ± SD of 3.0 ± 7.33 kg, sitagliptin-treated patients lost 1.1 ± 5.39 kg, and insulin-treated patients gained 0.6 ± 9.49 kg. There was a significant association between weight loss and a reduction in A1C and FBG with exenatide only and a reduction in blood pressure for all therapies. Weight loss was associated with some improvements in lipids, primarily in the GLP-1 receptor agonist group, with little association in the insulin group.

CONCLUSIONS

Weight reduction with GLP-1 receptor agonists was associated with a shift toward a more favorable cardiovascular risk profile. Outcome trials are needed to determine whether improvement in biomarkers translates into a reduction in cardiovascular events in patients with type 2 diabetes.
The general gould type integral with respect to a multisubmeasure
Authors: Gavriluţ Alina
Published: May 2010

In two earlier papers [GAVRILUŢ, A.: A Gould type integral with respect to a multisubmeasure, Math. Slovaca 58 (2008), 1–20] and [Gavriluţ, A.: On some properties of the Gould type integral with respect to a multisubmeasure, An. Ştiinţ. Univ. Al. I. Cuza Iaşi. Mat. (N.S.) 52 (2006), 177–194], we defined and studied a Gould type integral for a real valued, bounded function with respect to a multisubmeasure having finite variation. In this paper, we introduce and study the properties of a Gould type integral in the general setting: the function may be unbounded and the variation of the multisubmeasure may be infinite.
Unique solvability of a non-linear non-local boundary-value problem for systems of non-linear functional differential equations
Authors: Dilna N. , Ronto A.
Published: May 2010

General conditions for the unique solvability of a non-linear nonlocal boundary-value problem for systems of non-linear functional differential equations are obtained.
A note on a dirichlet problem with concave-convex nonlinearity
Authors: Galewski Marek
Published: May 2010

We prove an existence principle that would apply for elliptic problems with nonlinearity separating into a difference of derivatives of two convex functions in the case when the growth conditions are imposed only on the minuend term. We present abstract result and its application. We modify the so called dual variational method.
The Funj Region Pastoral Fulbe: From 'Exit' to 'Voice'
Authors: Osman Elhadi Ibrahim
Published: May 2010

The pastoral Fulbe were harassed by local people and authorities and were forced to lead a withdrawn life in the Funj region. They opted for 'exit' and adopted a highly mobile form of pastoralism. However, due to various recent socioeconomic and environmental transformations, they have shifted to a 'voice' strategy and have emerged as an important economic and political force. The Fulbe have become integrated into the national economy and wider society, and have started fighting for economic and political gains. They are also trained in the use of sophisticated firearms and have entered into politico-military alliances.
Pastoral Land Rights and Peacebuilding in North Kordofan: Policy and Legislative Challenges
Authors: Babiker Mustafa
Published: May 2010

This article focuses on the policy and legislative challenges posed by land claims made by different pastoral and agro-pastoral groups in North Kordofan. It takes as its point of departure the fact that many past and contemporary pastoral conflicts have their roots in struggles over land and that failure to implement the necessary legislative and administrative mechanisms to guard pastoral land rights can keep conflicts simmering, either openly or under the surface, with high social and economic costs. These issues are here considered in the context of the opportunities for both legal and administrative reform provided by the Naivasha Peace Agreement and the progress in its implementation thus far.
From Points to Forecasts: Predicting Invasive Species Habitat Suitability in the Near Term
Authors: Holcombe Tracy R. , Stohlgren Thomas J. , Jarnevich Catherine S.
Published: May 2010

We used near-term climate scenarios for the continental United States, to model 12 invasive plants species. We created three potential habitat suitability models for each species using maximum entropy modeling: (1) current; (2) 2020; and (3) 2035. Area under the curve values for the models ranged from 0.92 to 0.70, with 10 of the 12 being above 0.83 suggesting strong and predictable species-environment matching. Change in area between the current potential habitat and 2035 ranged from a potential habitat loss of about 217,000 km2, to a potential habitat gain of about 133,000 km2.
Thionation of Some α,β-Unsaturated Steroidal Ketones
Authors: Krstić Natalija M. , Bjelaković Mira S. , Dabović Milan M. , Pavlović Vladimir D.
Published: May 2010

The reactions of selected α,β-unsaturated steroidal ketones with Lawesson’s reagent (LR) in CH2Cl2 and toluene under the standard reaction conditions and with a combination of phosphorus pentasulfide with hexamethyldisiloxane (P4S10/HMDO) in 1,2-dichlorobenzene (ODCB) under microwave irradiation were investigated and for this purpose several cholestane, androstane and pregnane carbonyl derivatives were chosen. Depending on the reagent and the solvent, 19 new sulfur containing compounds, including dithiones 4c and 4d, α,β-unsaturated 3-thiones 3a-e, dimer-sulfides 2a-e, 1,2,4-trithiolanes 5a-e and phosphonotrithioates 6b-e were synthesized. All newly prepared compounds were characterized by IR, 1H- and 13C-NMR spectroscopy and elemental analysis.
Synthesis of Environmentally Responsive Polymers by Atom Transfer Radical Polymerization: Generation of Reversible Hydrophilic and Hydrophobic Surfaces
Authors: Mittal Vikas
Published: May 2010

Environmentally responsive poly(N-isopropylacrylamide) brushes were grafted from the surface of polymer particles or flat surfaces in order to generate reversible hydrophilic and hydrophobic surfaces. The use of atom transfer radical polymerization was demonstrated for the grafting of polymer brushes as it allows efficient control on the amount of grafted polymer. The polymer particles were generated with or without surfactant in the emulsion polymerization and their surface could be modified with the atom transfer radical polymerization (ATRP) initiator. The uniform functionalization of the surface with ATRP initiator was responsible for the uniform grafting of polymer brushes. The grafted brushes responded reversibly with changes in temperature indicating that the reversible responsive behavior could be translated to the particle surfaces. The particles were observed to adsorb and desorb protein and virus molecules by changing the temperatures below or higher than 32 °C. The initiator functionalized particles could also be adsorbed on the flat surfaces. The adsorption process also required optimization of the heat treatment conditions to form a uniform layer of the particles on the substrate. The grafted polymer brushes also responded to the changes in temperatures similar to the spherical particles studied through water droplets placed on the flat substrates.
Novel Feature Modelling the Prediction and Detection of sEMG Muscle Fatigue towards an Automated Wearable System
Authors: Al-Mulla Mohamed R. , Sepulveda Francisco
Published: May 2010

Surface Electromyography (sEMG) activity of the biceps muscle was recorded from ten subjects performing isometric contraction until fatigue. A novel feature (1D spectro_std) was used to extract the feature that modeled three classes of fatigue, which enabled the prediction and detection of fatigue. Initial results of class separation were encouraging, discriminating between the three classes of fatigue, a longitudinal classification on Non-Fatigue and Transition-to-Fatigue shows 81.58% correct classification with accuracy 0.74 of correct predictions while the longitudinal classification on Transition-to-Fatigue and Fatigue showed lower average correct classification of 66.51% with a positive classification accuracy 0.73 of correct prediction. Comparison of the 1D spectro_std with other sEMG fatigue features on the same dataset show a significant improvement in classification, where results show a significant 20.58% (p < 0.01) improvement when using the 1D spectro_std to classify Non-Fatigue and Transition-to-Fatigue. In classifying Transition-to-Fatigue and Fatigue results also show a significant improvement over the other features giving 8.14% (p < 0.05) on average of all compared features.
A Comprehensive Review of Glucose Biosensors Based on Nanostructured Metal-Oxides
Authors: Rahman Md. Mahbubur , Ahammad A. J. Saleh , Jin Joon-Hyung , Ahn Sang Jung , Lee Jae-Joon
Published: May 2010

Nanotechnology has opened new and exhilarating opportunities for exploring glucose biosensing applications of the newly prepared nanostructured materials. Nanostructured metal-oxides have been extensively explored to develop biosensors with high sensitivity, fast response times, and stability for the determination of glucose by electrochemical oxidation. This article concentrates mainly on the development of different nanostructured metal-oxide [such as ZnO, Cu(I)/(II) oxides, MnO2, TiO2, CeO2, SiO2, ZrO2, and other metal-oxides] based glucose biosensors. Additionally, we devote our attention to the operating principles (i.e., potentiometric, amperometric, impedimetric and conductometric) of these nanostructured metal-oxide based glucose sensors. Finally, this review concludes with a personal prospective and some challenges of these nanoscaled sensors.
OUTCOME OF ALLOGENEIC STEM CELL TRANSPLANTATION FOLLOWING REDUCED-INTENSITY CONDITIONINIG REGIMEN IN PATIENTS WITH IDIOPATHIC MYELOFIBROSIS: THE G.I.T.M.O. EXPERIENCE AND REVIEW OF THE LITERATURE
Authors: Patriarca Francesca , Bacigalupo Andrea , Sperotto Alessandra , Isola Miriam , Van Lint Maria Teresa , Iori Anna Paola , Di Bartolomeo Paolo , Musso Maurizio , Pioltelli Pietro , Visani Giuseppe , Iacopino Pasquale , Fanin Renato , Bosi Alberto
Published: May 2010

BackgroundAllogeneic stem cell transplantation (SCT) is a potentially curative treatment for myelofibrosis (MI),  though  limited by a high rate  of transplant-related mortality (TRM). .   In the present study we evaluate the outcome of MI patients undergoing an allogeneic SCT after reduced intensity conditioning (RIC) regimens  , and the impact of prognostic factors . Design and methods: Fifty two patients were transplanted in 26 Italian centres between 1998 and 2006. We analyzed the influence of patient and disease clinical features before SCT and of transplant procedures on TRM and overall survival (OS) by means of univariate and multivariate analyses.Results: At SCT,  median age was 52,5 years (32-68) and  89% of the patients had  an intermediate or high Dupriez score. Conditioning regimens were based on fludarabine plus busulphan in 27% of patients, thiotepa plus cyclophosphamide in 46% and miscellaneous drug combinations in the other 27% of cases.  Stem cells came from matched sibling donors for 75% of the patients and mismatched sibling or unrelated donors for the remaining 25%.   The cumulative incidence of engraftment at day 90 after transplant was 83% (95% CI, 0.87-0.97 ). The estimated  1-year TRM was 30%.  The estimated  3- -year event-free-survival (EFS) and OS after hematopoietic SCT was 44%  and 38% respectively.  In multivariate analysis , an higher leukocyte count and circulating blasts in the peripheral blood before SCT significantly reduced EFS and OS respectively. Interpretation and conclusions: We conclude that the extension of the disease before transplantation based on the presence of circulating blasts and high leukocyte counts significantly affected the outcome after HSCT
Progression from on-site to point-of-care fine needle aspiration service: Opportunities and challenges
Authors: Gupta Prabodh K
Published: May 2010

Background

Standard-of-care requires the availability of an efficient, economical and accurate on-site fine needle aspiration (FNA) service. Presence of a trained individual during the procedure ensures an improved patient care. Appropriate selection of the equipment, interaction with the clinicians and compliance with the various regulations during the procedure is essential. This is often done by an on-site FNA service. Organization and implementation of such a system in a large academic center is challenging.

Method

we reviewed the ambulatory care needs in the new Perelman Center for Advanced Medicine (PeCAM). Multiple (9) FNA sites have been established keeping in view the patient's convenience, clinic demands, various regulatory requirements and laboratory staff. Each location has dedicated FNA station with microscopes and supplies. In addition, state- ofthe -art technologies including a mobile FNA cart (Penn-A- Cart), remote specimen evaluation (TeleCyP) have been incorporated.

Results

The new set up is extremely efficient and much valued by the patients and the clinicians. It has improved patient care.

Conclusion

With necessary investments and resources a point-of-care FNA service has been created which has improved patient care. This, albeit with certain modifications may serve as a model for FNA service.
Audiovisual Presentations on a Handheld PC Are Preferred As an Educational Tool by NICU Parents
Authors: Cirelli J. , Goodstein M. , Bell T. , Liss J. , Alur P.
Published: May 2010

Background Health literacy is critical for understanding complex medical problems and necessary for the well being of the patient. Printed educational materials (PM) have limitations in explaining the dynamics of a disease process. Multimedia formats may be useful for enhancing the educational process.

Objective: To evaluate whether a printed format or animation with commentary on a handheld personal computer (PC) is preferred as an educational tool by parents of a baby in the NICU.

Methods: Parents evaluated two formats: A 1-page illustrated document from the American Heart Association explaining patent ductus arteriosus (PDA) and animation with commentary on a handheld PC that explained the physiology of PDA in 1 minute. The reading grade level of the PM was 8.6 versus 18.6 for the audio portion of the animated presentation. Parents viewed each format and completed a four-item questionnaire. Parents rated both formats and indicated their preference as printed, animation, or both.

Results: Forty-six parents participated in the survey. Parents preferred animation over PM (50% vs. 17.4%. p = 0.02); 39.1% expressed that the animation was excellent; whereas 4.3% expressed that the PM was excellent (p<0.001). The order of presentation of formats, sex, age, and educational level of parents did not influence the method preferred (p>0.05).

Conclusion: Parents preferred animation on a small screen handheld PC despite a much higher language level. Because handheld PCs are portable and inexpensive, they can be used effectively at the bedside with low-cost animation to enhance understanding of complex disease conditions.

Citation: Alur P, Cirelli J, Goodstein M, Bell T, Liss J. Audiovisual Presentations on a Handheld PC Are Preferred As an Educational Tool by NICU Parents. Appl Clin Inf 2010; 1: 142-148 http://dx.doi.org/10.4338/ACI-2010-01-RA-0005
Learning together: Kolb's experiential theory and its application
Authors: Akella Devi
Published: May 2010

This paper aims to make a limited contribution to Kolb's Experiential Learning Theory. An evaluation has been made of an empirically based personal narrative of the author's experiences, reflections and problems as an instructor of a management elective course at the undergraduate level. The paper examines the process of reflection, correction and learning from the perspective of the instructor and how the issue of race and origin of the student learners' can stimulate or hinder assimilation of knowledge within a classroom. The study reveals that it is essential for an educator to be critically reflective of his/her culture and that of his/her students to be able to assess their learning styles and adopt suitable and appropriate teaching pedagogies within the classroom. This paper draws attention towards types of teaching pedagogies, non traditional methods and aids and their effectiveness in educating students of diverse backgrounds. It provides insights about diversity within classrooms and its impact on teaching, pedagogies and learning styles of both educators and students, by portraying the journey of an educator and her process of self improvement.
The impact of cultural similarities and differences on performance in strategic partnerships: An integrative perspective
Authors: Meirovich Gavriel
Published: May 2010

This theoretical research endeavors to find common ground in the ostensibly inconsistent results of studies on the impact of cultural similarities and differences on strategic partnerships. Some findings suggested that partners have to possess similar cultural characteristics in order to achieve success while others showed that cultural distance had a positive effect on efficiency and the competitiveness of partnerships. This paper systematically analyzes the equivocal evidence of influence of both commonalities and differences on partnerships' outcomes, highlighting conditions under which they can be either beneficial or dysfunctional. Several propositions are formulated in regard to the role of qualitative and quantitative differences in both organizational and national cultures. Further, the theoretical and practical implications are also discussed.
A proposed improvement to the multilevel theory for hierarchical decision-making teams
Authors: Kang Mincheol
Published: May 2010

The multilevel theory proposed by Hollenbeck et al. identified a set of core variables that are central to accuracy in decision-making in hierarchical teams with distributed expertise. Following the identification of the limitations of the original core variables, a new set of core variables is proposed: (a) member validity, which represents the overall predictability of team members with regard to the correct decision and (b) hierarchical sensitivity, which represents the effectiveness of the leader's weightings of members' recommendations. To test the revised theory, a computational model called Team-Soar is used. The simulation results show that the small set of new core variables explains a large portion of the variance in the team decision accuracy and mediates the effects of other variables on the accuracy. The revised theory can be used as a conceptual vehicle to parsimoniously explain the performance of hierarchical decision-making teams. The theory could also be used to diagnose and train real teams in terms of the core variables.
The validity of Performance Environment Perception Scales: Environmental predictors of citizenship performance
Authors: Poropat Arthur E.
Published: May 2010

This research examined the validity of Performance Environment Perception Scales (PEPS), a new instrument designed to assess performance-relevant aspects of the work environment. A sample of 156 employees of an Australian university completed PEPS and their supervisors rated their task and citizenship performance. Confirmatory Factor Analysis showed PEPS to have a valid factor structure, and PEPS were found to be significantly correlated with citizenship performance, but not with task performance. Although this finding is consistent with theoretical predictions, PEPS are apparently the first measures of work environment perceptions that have confirmed this. Thus PEPS show promise as measures for use in future research and organizational development projects that focus on relationships between the work environment and performance. Limitations of the research and implications for the validity of PEPS, as well as for future research and practice, are discussed.
A theoretical model of transformational leadership and knowledge creation: The role of open-mindedness norms and leader–member exchange
Authors: Tse Herman HM , Mitchell Rebecca J
Published: May 2010

Considerable research attention has been devoted to understanding the importance of knowledge creation in organisations over the last decade. Research suggests that leadership plays an important role in knowledge-creation processes. Nonetheless, there is an important omission in knowledge creation research; namely, what are the underlying processes that underpin the implications of leadership for knowledge creation? This article aims to develop a theoretical model of leadership and knowledge creation by drawing on two contrasting leadership perspectives; that is transformational leadership and leader–member exchange (LMX), and the research on open-mindedness norms. Specifically, we argue why transformational leadership is related to knowledge creation, and also theorise how open-mindedness norms and LMX quality serve as underlying mechanisms to underpin the effect of transformational leadership on knowledge creation. We conclude with a discussion of implications of the model for theory and practice, and also suggest potential avenues for future research.
Process analysis and sensitivity study of regional ozone formation over the Pearl River Delta, China, during the PRIDE-PRD2004 campaign using the Community Multiscale Air Quality modeling system
Authors: Wang X. , Zhang Y. , Hu Y. , Zhou W. , Lu K. , Zhong L. , Zeng L. , Shao M. , Hu M. , Russell A. G.
Published: May 2010

Abstract. In this study, the Community Multiscale Air Quality (CMAQ) modeling system is used to simulate the ozone (O3) episodes during the Program of Regional Integrated Experiments of Air Quality over the Pearl River Delta, China, in October 2004 (PRIDE-PRD2004). The simulation suggests that O3 pollution is a regional phenomenon in the Pearl River Delta (PRD). Elevated O3 levels often occurred in the southwestern inland PRD, Pearl River estuary (PRE), and southern coastal areas during the 1-month field campaign. Three evolution patterns of simulated surface O3 are summarized based on different near-ground flow conditions. More than 75% of days featured interactions between weak synoptic forcing and local sea-land circulation. Integrated process rate (IPR) analysis shows that photochemical production is a dominant contributor to O3 enhancement from 09:00 to 15:00 local standard time in the atmospheric boundary layer over most areas with elevated O3 occurrence in the mid-afternoon. The simulated ozone production efficiency is 2–8 O3 molecules per NOx molecule oxidized in areas with high O3 chemical production. Precursors of O3 originating from different source regions in the central PRD are mixed during the course of transport to downwind rural areas during nighttime and early morning, where they then contribute to the daytime O3 photochemical production. The sea-land circulation plays an important role on the regional O3 formation and distribution over PRD. Sensitivity studies suggest that O3 formation is volatile-organic-compound-limited in the central inland PRD, PRE, and surrounding coastal areas with less chemical aging (NOx/NOy>0.6), but is NOx-limited in the rural southwestern PRD with aged air (NOx/NOy<0.3).
Preliminary evaluation of polarimetric parameters from a new dual-polarization C-band weather radar in an alpine region
Authors: Paulitsch H. , Teschl F. , Randeu W. L.
Published: May 2010

Abstract. The first operational weather radar with dual polarization capabilities was recently installed in Austria. The use of polarimetric radar variables rises several expectations: an increased accuracy of the rain rate estimation compared to standard Z-R relationships, a reliable use of attenuation correction methods, and finally hydrometeor classification. In this study the polarimetric variables of precipitation events are investigated and the operational quality of the parameters is discussed. For the new weather radar also several polarimetric rain rate estimators, which are based on the horizontal polarization radar reflectivity, ZH, the differential reflectivity, ZDR, and the specific differential propagation phase shift, KDP, have been tested. The rain rate estimators are further combined with an attenuation correction scheme. A comparison between radar and rain gauge indicates that ZDR based rain rate algorithms show an improvement over the traditional Z-R estimate. KDP based estimates do not provide reliable results, mainly due to the fact, that the observed KDP parameters are quite noisy. Furthermore the observed rain rates are moderate, where KDP is less significant than in heavy rain.
Current and future CO2 emissions from drained peatlands in Southeast Asia
Authors: Hooijer A. , Page S. , Canadell J. G. , Silvius M. , Kwadijk J. , Wösten H. , Jauhiainen J.
Published: May 2010

Abstract. Forested tropical peatlands in Southeast Asia store at least 42 000 Million metric tonnes (Mt) of soil carbon. Human activity and climate change threatens the stability of this large pool, which has been decreasing rapidly over the last few decades owing to deforestation, drainage and fire. In this paper we estimate the carbon dioxide (CO2) emissions resulting from drainage of lowland tropical peatland for agricultural and forestry development which dominates the perturbation of the carbon balance in the region. Present and future emissions from drained peatlands are quantified using data on peatland extent and peat thickness, present and projected land use, water management practices and decomposition rates. Of the 27.1 Million hectares (Mha) of peatland in Southeast Asia, 12.9 Mha had been deforested and mostly drained by 2006. This latter area is increasing rapidly because of increasing land development pressures. Carbon dioxide (CO2) emission caused by decomposition of drained peatlands was between 355 Mt y−1 and 855 Mt y−1 in 2006 of which 82% came from Indonesia, largely Sumatra and Kalimantan. At a global scale, CO2 emission from peatland drainage in Southeast Asia is contributing the equivalent of 1.3% to 3.1% of current global CO2 emissions from the combustion of fossil fuel. If current peatland development and management practices continue, these emissions are predicted to continue for decades. This warrants inclusion of tropical peatland CO2 emissions in global greenhouse gas emission calculations and climate mitigation policies. Uncertainties in emission calculations are discussed and research needs for improved estimates are identified.
Modelling and quantifying the effect of heterogeneity in soil physical conditions on fungal growth
Authors: Pajor R. , Falconer R. , Hapca S. , Otten W.
Published: May 2010

Abstract. Despite the importance of fungi in soil ecosystem services, a theoretical framework that links soil management strategies with fungal ecology is still lacking. One of the key challenges is understanding how the complex geometrical shape of pores in soil affects fungal spread and species interaction. Progress in this area has long been hampered by a lack of experimental techniques for quantification. In this paper we use X-ray computed tomography to quantify and characterize the pore geometry at microscopic scales (30 μm) that are relevant for fungal spread in soil. We analysed the pore geometry for replicated samples with bulk-densities ranging from 1.2–1.6 g/cm3. The bulk-density of soils significantly affected the total volume, mean pore diameter and connectivity of the pore volume. A previously described fungal growth model comprising a minimal set of physiological processes required to produce a range of phenotypic responses was used to analyse the effect of these geometric descriptors on fungal invasion, and we showed that the degree and rate of fungal invasion was affected mainly by pore volume and pore connectivity. The presented experimental and theoretical framework is a significant first step towards understanding how environmental change and soil management impact on fungal diversity in soils.
On the reproducibility and repeatability of laser absorption spectroscopy measurements for δ2H and δ18O isotopic analysis
Authors: Penna D. , Stenni B. , Šanda M. , Wrede S. , Bogaard T. A. , Gobbi A. , Borga M. , Fischer B. M. C. , Bonazza M. , Chárová Z.
Published: May 2010

Abstract. The aim of this study was to analyse the reproducibility of off-axis integrated cavity output spectroscopy (OA-ICOS)-derived δ2H and δ18O measurements on a set of 35 water samples by comparing the performance of four laser spectroscopes with the performance of a conventional mass spectrometer under typical laboratory conditions. All samples were analysed using three different schemes of standard/sample combinations and related data processing to assess the improvement of results compared with mass spectrometry. The repeatability of the four OA-ICOS instruments was further investigated by multiple analyses of a sample subset to evaluate the stability of δ2H and δ18O measurements. Results demonstrated an overall agreement between OA-ICOS-based and mass spectrometry-based measurements for the entire dataset. However, a certain degree of variability existed in precision and accuracy between the four instruments. There was no evident bias or systematic deviations from the mass spectrometer values, but random errors, which were apparently not related to external factors, significantly affected the final results. Our investigation revealed that analytical precision ranged from ±0.56‰ to 1.80‰ for δ2H and from ±0.10‰ to 0.27‰ for δ18O measurements, with a marked variability among the four instruments. The overall capability of laser instruments to reproduce stable results with repeated measurements of the same sample was acceptable, and there were general differences within the range of the analytical precision for each spectroscope. Hence, averaging the measurements of three identical samples led to a higher degree of accuracy and eliminated the potential for random deviations.
Response of the ice cap Hardangerjøkulen in southern Norway to the 20th and 21st century climates
Authors: Giesen R. H. , Oerlemans J.
Published: May 2010

Abstract. Glaciers respond to mass balance changes by adjusting their surface elevation and area. These properties in their turn affect the local and area-averaged mass balance. To incorporate this interdependence in the response of glaciers to climate change, models should include an interactive scheme coupling mass balance and ice dynamics. In this study, a spatially distributed mass balance model, comprising surface energy balance calculations, was coupled to a vertically integrated ice-flow model based on the shallow ice approximation. The coupled model was applied to the ice cap Hardangerjøkulen in southern Norway. The available glacio-meteorological records, mass balance and glacier length change measurements were utilized for model calibration and validation. Forced with meteorological data from nearby synoptic weather stations, the coupled model realistically simulated the observed mass balance and glacier length changes during the 20th century. The mean climate for the period 1961–1990, computed from local meteorological data, was used as a basis to prescribe climate projections for the 21st century at Hardangerjøkulen. For a linear temperature increase of 3 °C from 1961–1990 to 2071–2100, the modelled net mass balance soon becomes negative at all altitudes and Hardangerjøkulen disappears around the year 2100. The projected changes in the other meteorological variables could at most partly compensate for the effect of the projected warming.
Presence of peripheral arthritis and male sex predicting continuation of anti–tumor necrosis factor therapy in ankylosing spondylitis: An observational prospective cohort study from the South Swedish arthritis treatment group register
Authors: Kristensen L. E. , Karlsson J. A. , Englund M. , Petersson I. F. , Saxne T. , Geborek P.
Published: May 2010

Objective

To examine clinical characteristics as possible predictors of long‐term treatment continuation with adalimumab, etanercept, and infliximab in ankylosing spondylitis (AS) patients who had never taken biologics treated in clinical practice.

Methods

Patients in southern Sweden with active AS starting biologic therapy for the first time between October 1999 and December 2008 (n = 243, 75% men) were included in a structured clinical followup over 2 years. Patients with clinical spondylitis had not responded to at least 2 nonsteroidal antiinflammatory drugs, whereas patients who also had peripheral arthritis (n = 121) had additionally failed at least 1 conventional disease‐modifying antirheumatic drug (DMARD) treatment course. The mean ± SD age at inclusion was 43 ± 12 years, with a mean ± SD disease duration prior to treatment of 16 ± 12 years.

Results

The 2‐year drug continuation rate was 74%. Male sex (hazard ratio [HR] of premature discontinuation 0.36 [95% confidence interval (95% CI) 0.19–0.68]) and the presence of peripheral arthritis (HR 0.49 [95% CI 0.27–0.88]) were found to be significant predictors of better drug survival. Furthermore, a trend was seen for more favorable drug continuation on treatment with etanercept as compared with infliximab (HR 0.50 [95% CI 0.25–1.04], P = 0.062), whereas no differences were found comparing the 3 anti–tumor necrosis factor agents in other ways. Higher baseline C‐reactive protein level (HR 0.99 [95% CI 0.97–1.00], P = 0.12) and concomitant treatment with nonbiologic DMARDs (HR 0.61 [95% CI 0.34–1.10], P = 0.10) also showed trends to entail better drug adherence.

Conclusion

AS patients in this study have an excellent 2‐year drug survival rate of 74%. Significant predictors for treatment continuation in this study were male sex and the presence of peripheral arthritis.
Paraoxonase gene mutations in amyotrophic lateral sclerosis
Authors: Ticozzi Nicola , LeClerc Ashley Lyn , Keagle Pamela J. , Glass Jonathan D. , Wills Anne‐Marie , van Blitterswijk Marka , Bosco Daryl A. , Rodriguez‐Leyva Ildefonso , Gellera Cinzia , Ratti Antonia , Taroni Franco , McKenna‐Yasek Diane , Sapp Peter C. , Silani Vincenzo , Furlong Clement E. , Brown Robert H. , Landers John E.
Published: May 2010

Three clustered, homologous paraoxonase genes (PON1, PON2, and PON3) have roles in preventing lipid oxidation and detoxifying organophosphates. Recent reports describe a genetic association between the PON genes and sporadic amyotrophic lateral sclerosis (ALS). We now report that in genomic DNA from individuals with familial and sporadic ALS, we have identified at least 7 PON gene mutations that are predicted to alter PON function. ANN NEUROL 2010
Preparation and properties of α‐chitin‐whisker‐reinforced hyaluronan–gelatin nanocomposite scaffolds
Authors: Hariraksapitak Parintorn , Supaphol Pitt
Published: May 2010

Tissue scaffolds made of naturally derived polymers present poor mechanical properties, which may limit their actual utilization in certain areas where high strength is a key criterion. This study was aimed at developing tissue scaffolds from a 50 : 50 w/w blend of hyaluronan (HA) and gelatin (Gel) that contained different amounts of acid‐hydrolyzed α‐chitin whiskers (CWs) by a freeze‐drying method. The weight ratios of the CWs to the blend were 0–30%. These scaffolds were characterized for their physical, physicochemical, mechanical, and biological properties. Regardless of the CW content, the average pore size of the scaffolds ranged between 139 and 166 μm. The incorporation of 2% CWs in the HA–Gel scaffolds increased their tensile strength by about two times compared to those of the other groups of the scaffolds. Although the addition of 20–30% CWs in the scaffolds improved their thermal stability and resistance to biodegradation, the scaffolds with 10% CWs were the best for supporting the proliferation of cultured human osteosarcoma cells (SaOS‐2). © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
The influence of crosslinking agents on the morphology and electro‐optical performances of PDLC films
Authors: Kashima Miki , Cao Hui , Meng Qingyong , Liu Huijing , Wang Ding , Li Fasheng , Yang Huai
Published: May 2010

The morphology of polymer‐dispersed liquid crystal (PDLC) has a major impact on its electro‐optic properties. The PDLC was prepared by photochemical polymerization from UV‐curable monomers/crosslinking agent/initiator/LC mixture. The influences of crosslinking agents on the PDLC system had been studied. The microstructures of the PDLC were strongly influenced by the insertion of polyethylene glycol (600) diacrylate (PEGDA 600) crosslinker, relatively long and flexible branch, and diethylene glycol diacrylate (DEGDA) crosslinker along the network bone. The relative weight ratio of crosslinking agents and polymerization temperature had a significant effect on the LC domain size, and which resulted in influencing the electro‐optic properties of PDLC. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
High‐frequency dielectric characterization for liquid crystalline polyimide/SiO2 nanocomposites
Authors: Ho Czung‐Yu , Chang Che‐Chiang , Lee Jiunn‐Yih
Published: May 2010

In this study, we investigated the influence of frequency, film thickness, and SiO2 content on the dielectric constant (K) and loss tangent (tan δ) of liquid crystalline polyimide (LCPi) and liquid crystalline polyimide/SiO2 (LCPi/SiO2) nanocomposites in a high frequency environment. We tested the loss tangent of the LCPi and LCPi/SiO2 nanocomposites within the high frequency 1 MHz to 3 GHz range, and determined its value to be between 0.01 and 0.001. In addition, we found a formant for frequencies ranging from 0.5 GHz to 1 GHz. We also inferred from the dielectric loss graphs of films with different thicknesses that the formants of the loss tangent shifted toward higher frequencies with increasing thicknesses. When measuring the dielectric constant at high frequencies, we found that the dielectric constant decreased markedly with increased SiO2 contents. Using the dielectric constant of high‐frequency circuit board materials as the standard, the dielectric constant of the LCPi/SiO2 nanocomposites at the frequency range from 1 MHz to 3 GHz was found to be as high as 2.2–3.4, thereby confirming the viability of LCPi/SiO2 nanocomposites as candidate materials for high‐frequency circuit board. In addition, the volume resistivity (ρV) of the LCPi and LCPi/SiO2 nanocomposites also increased with increased SiO2 contents. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Studies on α to β phase transformations in mechanically deformed PVDF films
Authors: R. P. Vijayakumar , Khakhar Devang V. , Misra Ashok
Published: May 2010

PVDF cast films were drawn at different temperatures to different draw ratios at constant draw rate to understand the mechanism of α to β phase transformation during mechanical deformation. WAXD and FTIR studies were carried out to determine the formation and content of β phase in the drawn films. Lower stretch temperatures gave higher fractions of β phase. The cast PVDF films were also drawn at suitable temperatures below the PVDF ambient melting point to the draw ratio of 6.4. The highest fraction of β phase obtained in these ultra drawn films was 0.98. SALS studies carried out for films at different stretch ratios show the change in spherulitic structure with the stretching parameters and give information for the understanding of phase transformation during stretching of PVDF films. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of vinyl pivalate/vinyl acetate comonomer composition on the self‐assembled morphology of poly(vinyl alcohol) prepared by in situ fibrillation: Preparation of PVA with a spherical morphology
Authors: Chirowodza Helen , Zou Mingxuan , Sanderson Ronald D.
Published: May 2010

The photoinitiated copolymerization of vinyl pivalate (VPi) and vinyl acetate (VAc) was carried out in bulk. Varying monomer feed ratios of VPi/VAc (mol %/mol %) of 100/0, 90/10, 60/40, 50/50, and 30/70 were used. Polyvinyl alcohol (PVA) with s‐diad contents ranging from 61.8% to 55.7% was obtained. The morphology and thermal properties of the different PVA samples were investigated. PVA prepared from PVPi homopolymer resulted in PVA with a well‐aligned microfibrillar structure. With a decrease in the VPi content in the precursor polymer, the fibrous morphology was gradually lost, resulting in PVA with mixtures of fibrillar and spherical structures. When the PVPi content was 38.5 mol %, only spherical particles were observed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010