bluuebunny/crossref_metadata_2025 huggingface dataset:
Chromium(VI) oxide oxidation of non‐ethoxylated and ethoxylated alcohols for determination by electrospray ionization mass spectrometry
Authors: Beneito‐Cambra Miriam , Bernabé‐Zafón Virginia , Simó‐Alfonso Ernesto F. , Ramis‐Ramos Guillermo
Published: June 2010

A new derivatization procedure to increase the sensitivity of electrospray ionization mass spectrometry (ESI‐MS) to non‐ethoxylated and ethoxylated alcohols was investigated. The analytes were oxidized with chromium(VI) oxide and the resulting carboxylic and ethoxy‐carboxylic acids were isolated by extraction with ethyl acetate; the extracts were alkalinized and infused into the ESI‐MS system working in the negative‐ion mode. The yields of the combined oxidation‐extraction were ca. 100% for non‐ethoxylated fatty alcohols dissolved in acetone and they decreased moderately in samples containing increasing amounts of water (e.g., a 75% yield was obtained with 50% water). Ethoxylated alcohols with more than two ethylene oxide units resulted in yields of ca. 60%. Low limits of detection (LODs) were obtained when the procedure was applied to the analysis of body‐care products and cosmetics containing fatty alcohols, e.g., in a varicose‐vein cream, the LODs were 25 µg cetyl alcohol and 7.5 µg stearyl alcohol (detected as palmitic acid and stearic acid, respectively) per gram of sample. High molecular mass alcohols were also detected in seawater after pre‐concentration by solid‐phase extraction. Thus, the proposed method is particularly valuable for use in industrial samples having complex matrices and in environmental samples and it is competitive with other methods for the analysis of trace amounts of fatty alcohols. Copyright © 2010 John Wiley & Sons, Ltd.
Robotic tools for deep water archaeology: Surveying an ancient shipwreck with an autonomous underwater vehicle
Authors: Bingham Brian , Foley Brendan , Singh Hanumant , Camilli Richard , Delaporta Katerina , Eustice Ryan , Mallios Angelos , Mindell David , Roman Christopher , Sakellariou Dimitris
Published: June 2010

The goals of this article are twofold. First, we detail the operations and discuss the results of the 2005 Chios ancient shipwreck survey. This survey was conducted by an international team of engineers, archaeologists, and natural scientists off the Greek island of Chios in the northeastern Aegean Sea using an autonomous underwater vehicle (AUV) built specifically for high‐resolution site inspection and characterization. Second, using the survey operations as context, we identify the specific challenges of adapting AUV technology for deep water archaeology and describe how our team addressed these challenges during the Chios expedition. After identifying the state of the art in robotic tools for deep water archaeology, we discuss opportunities in which new developments and research (e.g., AUV platforms, underwater imaging, remote sensing, and navigation techniques) will improve the rapid assessment of deep water archaeological sites. It is our hope that by reporting on the Chios field expedition we can both describe the opportunities that AUVs bring to fine‐resolution seafloor site surveys and elucidate future opportunities for collaborations between roboticists and ocean scientists. © 2010 Wiley Periodicals, Inc.
An investigation of the use of active infrared thermography to detect localized surface anomalies in lumber
Authors: van Dyk Herman , Lemaster Richard L.
Published: June 2010

Efforts are being pursued to improve and automate processes for grading, trimming, and cutting up softwood and hardwood lumber by automated, non‐contact, non‐labor‐intensive methods. Existing technology for detecting defects in lumber has focused heavily on the use of charged coupled device scanners or cameras, but these devices are limited by inherent color differences of the material. Thermography has been proven to detect knots in lumber, but the use of active thermography has not been investigated in terms of detecting dents, holes, and gouges. This research focused on four heating techniques, i.e. defect side heating, back side heating, forced air heating, and pulsed thermography, to detect dents, holes, gouges, and knots. All four heating methods proved successful for at least two defect types. Implementation of these techniques in an industrial setting will depend on the requirements of the manufacturer and the physical limitations of the industrial line. SCANNING 32: 219–223, 2010. © 2010 Wiley Periodicals, Inc.
Fabrication of Metallized Nanopores in Silicon Nitride Membranes for Single‐Molecule Sensing
Authors: Wei Ruoshan , Pedone Daniel , Zürner Andreas , Döblinger Markus , Rant Ulrich
Published: June 2010

The fabrication and characterization of a metallized nanopore structure for the sensing of single molecules is described. Pores of varying diameters (>10 nm) are patterned into free‐standing silicon nitride membranes by electron‐beam lithography and reactive ion etching. Structural characterization by transmission electron microscopy (TEM) and tomography reveals a conical pore shape with a 40° aperture. Metal films of Ti/Au are vapor deposited and the pore shape and shrinking are studied as a function of evaporated film thickness. TEM tomography analysis confirms metalization of the inner pore walls as well as conservation of the conical pore shape. In electrical measurements of the transpore current in aqueous electrolyte solution, the pores feature very low noise. The applicability of the metallized pores for stochastic sensing is demonstrated in real‐time translocation experiments of single λ‐DNA molecules. We observe exceptionally long‐lasting current blockades with a fine structure of distinct current levels, suggesting an attractive interaction between the DNA and the PEGylated metallic pore walls.
Maternal serum placental growth hormone, but not human placental lactogen or insulin growth factor‐1, is positively associated with fetal growth in the first half of pregnancy
Authors: Pedersen N. G. , Juul A. , Christiansen M. , Wøjdemann K. R. , Tabor A.
Published: June 2010

Objective

To investigate if maternal levels of human placental lactogen (hPL), placental growth hormone (PGH) and insulin‐like growth factor‐1 (IGF‐1) are associated with growth rate of the biparietal diameter (BPD) in the first half of pregnancy.

Methods

Data on 8215 singleton fetuses from the Copenhagen First Trimester Study with measurements of BPD from ultrasound scans performed at weeks 11–14 and 17–21 of pregnancy were analyzed. Growth rate was defined as millimeters of growth/day of BPD between the two scans. Fetuses with growth rate below the 2.5th centile (low growth rate, n = 203) and above the 97.5th centile (high growth rate, n = 203) were identified. As a reference group 212 fetuses with growth rate around the median were identified (intermediate growth rate). Out of the 618 selected cases in the three growth rate groups a total of 463 cases had a blood sample taken at the time of first‐trimester ultrasound (5.6% of the original sample size of 8215 pregnancies). The maternal blood serum concentrations of hPL, PGH and IGF‐1 were determined in the three different growth‐rate groups. Linear regression analysis without adjustment and with adjustment for known and potential confounders was used to compare serum levels between the groups.

Results

Simple linear regression showed a difference in serum level of log10PGH between the high and intermediate growth‐rate groups (P = 0.037). When adjusted for maternal weight and crown–rump length, multiple linear regression analysis confirmed this difference, as fetuses with high growth rates had a 12% (95% confidence interval, 2–20%; P = 0.009) higher maternal serum level of PGH than those with intermediate growth rates. No differences in hPL and IGF‐1 levels between the three different growth‐rate groups were found after simple and multiple linear regression analysis.

Conclusion

Maternal PGH levels are higher in women carrying fetuses with high first‐trimester growth rates than in controls, both in a simple unadjusted analysis and in analyses adjusted for known and potential confounders. Thus, PGH may be involved in fetal growth regulation as early as in the first trimester of pregnancy. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Open Access Publishing: An Initial Discussion of Income Sources, Scholarly Journals and Publishers
Authors: Polydoratou Panayiota , Palzenberger Margit , Schimmer Ralf , Mele Salvatore
Published: June 2010

The Study for Open Access Publishing (SOAP) project is one of the initiatives undertaken to explore the risks and opportunities of the transition to open access publishing. Some of the early analyses of open access journals listed in the Directory of Open Access Journals (DOAJ) show that more than half of the open access publishing initiatives were undertaken by smaller publishers, learned societies and few publishing houses that own a large number of journal titles. Regarding income sources as means for sustaining a journal’s functions, “article processing charges", "membership fee" and "advertisement" are the predominant options for the publishing houses; "subscription to the print version of the journal", "sponsorship" and somewhat less the "article processing charges" have the highest incidences for all other publishers.
Diagnosis and Treatment of Diffuse Cavernous Hemangioma of the Rectum: Report of 17 Cases
Authors: Wang Han Tao , Gao Xian Hua , Fu Chuan Gang , Wang Lie , Meng Rong Gui , Liu Lian Jie
Published: June 2010

Background

Diffuse cavernous hemangioma of the rectum (DCHR) is a rare benign vascular disease, which is often misdiagnosed and difficult to treat.

Methods

Seventeen cases of DCHR in our hospitals from 1995 to 2009 were identified. The detailed data of diagnosis, treatment, and prognosis were carefully studied.

Results

Seven, three, two, and one patient were mistaken as having hemorrhoids, colitis, portal hypertension, and rectal polypus, respectively. The mean delay time between initial symptoms and final diagnosis was 17.63 years (range = 0–48 years). Colonoscopy and MRI were important in the diagnosis of DCHR because of their high positive rates and specific features. All of the lesions originated from the dentate line, extending to the proximal colorectal wall. Most of the lesions were found to be restricted to the rectosigmoid wall and the rectal mesentery. Involvement of right gluteus maximus and right leg was revealed by MRI in two patients. After admission, six patients underwent coloanal sleeve anastomosis and seven patients underwent pull‐through transection and coloanal anastomosis. The latter procedure was superior to the former with respect to length of operation, intraoperative blood loss, intraoperative blood transfusion, and perioperative complications.

Conclusion

DCHR is often misdiagnosed. Preoperative colonoscopy and MRI are essential in making the correct diagnosis and to depict the extent of the lesion accurately. Due to its origination from the dentate line and the involvement of the whole layer of the rectal wall and the rectal mesentery, the treatment of choice for DCHR is complete resection by the pull‐through transection and coloanal anastomosis.
Variation in Fatty Acid Composition in Indian Germplasm of Sesame
Authors: Mondal Nupur , Bhat K. V. , Srivastava P. S.
Published: June 2010

A germplasm collection of 33 entries comprising 22 sesame (Sesamum indicum L.) cultivars, 4 landraces of S. mulayanum and 7 other accessions of 4 wild species were analyzed for the fatty acid compositions of their seed oil. The entries varied widely in their fatty acid compositions. The percentage content of oleic, linoleic, palmitic and erucic acids ranged between 36.7–52.4, 30.4–51.6, 9.1–14.8 and 0.0–8.0, respectively. Linolenic and arachidonic acids were the minor constituents but varied widely in wild species. Oleic and linoleic were the major fatty acids with mean values of 45.9 and 40.5%, respectively and the mean of their combined values was 86.4%. The polyunsaturated fatty acid (PUFA) compositions ranged from 30.9 to 52.5% showing high variation in PUFA in the germplasm. Linoleic acid content was very high in one landrace (47.8) and one accession each of three wild species, S. mulayanum (49.3), S. malabaricum (48.2) and S. radiatum (51.6%). Use of fatty acid ratios to estimate the efficiency of biosynthetic pathways resulted in high oleic and low linoleic desaturation ratios and consequently high linoleic and very low linolenic acid contents in seed oil. The results of this study provided useful background information on the germplasm and also identified a few accessions having high linoleic acid which can be used for developing cultivars with desirable fatty acid compositions.
Nonlinear modelling of target leverage with latent determinant variables — new evidence on the trade‐off theory
Authors: Sabiwalsky Ralf
Published: June 2010

This paper applies a nonlinear structural equation framework to analyze dynamic capital structure choice. I test the hypothesis that firms adjust leverage towards a time‐varying target, and that this target is determined by solving an optimization problem: optimal leverage is achieved when the difference between the expected net present value of the tax shield and the expected net present value of the costs of insolvency is maximized. Results indicate that firm size is an important determinant of the validity of this simple trade‐off model.
Transverse instability of surface solitary waves. Part 2. Numerical linear stability analysis
Authors: KATAOKA TAKESHI
Published: June 2010

In a previous work, Kataoka & Tsutahara (J. Fluid Mech., vol. 512, 2004a, p. 211) proved the existence of longitudinally stable but transversely unstable surface solitary waves by asymptotic analysis for disturbances of small transverse wavenumber. In the present paper, the same transverse instability is examined numerically for the whole range of solitary-wave amplitudes and transverse wavenumbers of disturbances. Numerical results show that eigenvalues and eigenfunctions of growing disturbance modes agree well with those obtained by the asymptotic analysis if the transverse wavenumber of the disturbance is small. As the transverse wavenumber increases, however, the growth rate of the disturbance, which is an increasing function for small wavenumbers, reaches a maximum and finally falls to zero at some finite wavenumber. Thus, there is a high-wavenumber cutoff to the transverse instability. For higher amplitude, solitary waves become longitudinally unstable, and the dependence of the eigenvalues on the transverse wavenumber exhibits various complicated patterns. We found that such eigenvalues versus transverse wavenumber can be simply grouped into three basic classes.
Gymnolaemate bryozoans from the Algarve (southern Portugal): new species and biogeographical considerations
Authors: Souto Javier , Reverter-Gil Oscar , Fernández-Pulpeiro Eugenio
Published: June 2010

Three sampling surveys were carried out, by SCUBA diving, in the Algarve (southern Portugal) in December 2007. A total of 57 species of gymnolaemate Bryozoa were identified. Of these, eight species were new to science (Mollia cristinae sp. nov., Hippoporina teresae sp. nov., Schizoporella spinosa sp. nov., Fenestrulina inesae sp. nov., Celleporina derungsi sp. nov., Dentiporella saldanhai sp. nov., Rhynchozoon celestinoi sp. nov. and Rhynchozoon rosae sp. nov.). Another 16 species are cited for the first time in Portuguese waters; of these, Stephanollona contracta is cited for the first time in European continental waters. Reference material deposited in several collections was also revised, and lectotypes and paralectotypes were selected for Mollia multijuncta and Dentiporella sardonica, species subjected to diverse interpretations. In addition Rhynchozoon revelatus was found to be a junior synonym of D. sardonica. The species collected in the study area reflect the existence of Lusitanian, Mauretanian and Mediterranean influences; the latter influence is of interest as the Mediterranean species found were previously considered endemic to the Mediterranean Sea and are usually found in shallow waters. Finally, a large degree of intracolonial variability was observed in some of the species studied, especially in Stephanollona armata, which may be taken into account in studies of the geographical variability and differentiation of cryptic species.
Morphological variation in the Indian gooseberries (Phyllanthus emblica and Phyllanthus indofischeri) and the chloroplast trnL (UAA) intron as candidate gene for their identification
Authors: Sangeetha N. , Mercy S. , Kavitha M. , Selvaraj Divya , Sathishkumar R. , Ganesh D.
Published: June 2010

Indian gooseberry, popularly known as amla, is harvested from two species of Phyllanthus, namely Phyllanthus emblica and Phyllanthus indofischeri. Although these two species are characterized on vegetative and reproductive features, development of reliable and authentic identification based on molecular approaches is necessary for precise identification. Most of the commercial orchards of Indian gooseberry are established with mixture of the two species. Introduction of unauthentic clones and seedlings in the establishment of orchards and differences in the growth of these two species under different elevations are the major constrains in identification. The present work aims to study the changes in vegetative and reproductive features under different elevations and to develop a simple molecular tool for precise identification of these two species based on single nucleotide polymorphisms in trnL (UAA) intron sequences of chloroplast DNA. Genomic DNA of leaf tissues of P. emblica and P. indofischeri, collected from the authentic source, was subjected to polymerase chain reaction amplification using trnL (UAA) intron gene-specific primers. The amplified product with the molecular weight of 540 bp was sequenced and used as reference for identification of these two species. The trnL (UAA) introns sequenced from 60 individual trees in three different orchards were compared with trnL (UAA) intron of authentic samples, and confirmed that these orchards have 76% population of P. indofischeri and remaining 24% is occupied by P. emblica. Thus, trnL (UAA) intron is a potential DNA marker for precise identification of these two species. The importance of the present study and its practical application in genetic improvement of Indian gooseberry are discussed.
Collaborative Governance and Civic Empowerment: A Discussion of Investing in Democracy: Engaging Citizens in Collaborative Governance
Authors: Weir Margaret
Published: June 2010

Whether as a solution to problems of political legitimacy or social mistrust, as a way of involving civil society, or as a method of crafting more effective “third way” policies, collaborative governance has been a topic of renewed interest for political scientists and policy intellectuals. Carmen Sirianni's Investing in Democracy: Engaging Citizens in Collaborative Governance (Brookings, 2009) is an important new book that raises many of these issues. Perspectives on Politics is a forum for raising questions of interest to a broad range of political scientists. In this symposium, we have asked a number of prominent political scientists and policy analysts to assess the book and to address two broader questions: in what ways does the book draw from and add to political science scholarship, and in what ways does political science scholarship help to shed light on the book's core themes?
Collaborative Governance and Civic Empowerment: A Discussion ofInvesting in Democracy: Engaging Citizens in Collaborative Governance
Authors: Coles Romand
Published: June 2010

Whether as a solution to problems of political legitimacy or social mistrust, as a way of involving civil society, or as a method of crafting more effective “third way” policies, collaborative governance has been a topic of renewed interest for political scientists and policy intellectuals. Carmen Sirianni'sInvesting in Democracy: Engaging Citizens in Collaborative Governance(Brookings, 2009) is an important new book that raises many of these issues.Perspectives on Politicsis a forum for raising questions of interest to a broad range of political scientists. In this symposium, we have asked a number of prominent political scientists and policy analysts to assess the book and to address two broader questions: in what ways does the book draw from and add to political science scholarship, and in what ways does political science scholarship help to shed light on the book's core themes?
Collaborative Governance and Civic Empowerment: A Discussion of Investing in Democracy: Engaging Citizens in Collaborative Governance
Authors: Deneen Patrick J.
Published: June 2010

Whether as a solution to problems of political legitimacy or social mistrust, as a way of involving civil society, or as a method of crafting more effective “third way” policies, collaborative governance has been a topic of renewed interest for political scientists and policy intellectuals. Carmen Sirianni's Investing in Democracy: Engaging Citizens in Collaborative Governance (Brookings, 2009) is an important new book that raises many of these issues. Perspectives on Politics is a forum for raising questions of interest to a broad range of political scientists. In this symposium, we have asked a number of prominent political scientists and policy analysts to assess the book and to address two broader questions: in what ways does the book draw from and add to political science scholarship, and in what ways does political science scholarship help to shed light on the book's core themes?
The Liberals' Moment: The McGovern Insurgency and the Identity Crisis of the Democratic Party. By Bruce Miroff. Lawrence: University Press of Kansas, 2007. 356p. $29.95 cloth, $17.95 paper.
Authors: Spragens Thomas A.
Published: June 2010

In his book, Bruce Miroff provides a captivating account of the ill-fated 1972 presidential campaign of George McGovern. Indeed, given Miroff's access and diligence in interviewing many of the major players, this is likely to be the definitive study of that campaign for the foreseeable future. To read it is to relive the events of a crucial episode in the career of American liberalism—and also to relive the emotions of hope, anguish, frustration, and dismay that attended them. In addition to providing such a wonderful narrative and judicious assessment of this campaign, Miroff also wants to argue that these events marked the onset of and contributed in some ways to what he calls “the identity crisis of the Democratic Party.”
Getting the Left Right: The Transformation, Decline, and Reformation of American Liberalism. By Thomas A. Spragens, Jr. Lawrence: University Press of Kansas, 2009. 304p. $34.95.
Authors: Miroff Bruce
Published: June 2010

Why have American liberals been losing most political contests in recent decades? Theorist Thomas A. Spragens argues that the core of liberalism's problems lies in an ill-conceived transformation in public philosophy. In a “political treatise informed by scholarly resources” (p. ix), he defends an older liberalism, which he describes as populist and progressive, and decries a new one that he associates with the social justice approach of John Rawls. Shifting his attention back and forth from theory to practice, Spragens constructs an argument that liberalism will not recoup its political fortunes until it rediscovers its “populist heart” (p. xvii). Bearing some resemblance to previous treatises by Richard Rorty and Michael Sandel (along with important differences that Spragens notes), Getting the Left Right is provocative and powerful as theoretical critique and advocacy, but is less effective in providing a historical explanation for contemporary liberalism's troubled state.
Offensive Political Theory
Authors: Rehfeld Andrew
Published: June 2010

Penn State's decision to eliminate political theory set off existential angst about the status of political theory in the discipline. The organized, defensive responses to that decision failed to answer the central question it posed: Is “political theory” social science, and if not, why does it belong? I argue that social scientific political theory is political science and its many strains—conceptual, normative, and explanatory—belong in the discipline on their own terms. Humanistic research, like dermatology or music theory, is not political science and as such it should find another home. By explaining why (and what kinds of) political theory is political science this article may wind up being offensive in both senses of the word. But it is meant to be in service to a more secure, stable, and productive interdisciplinary future for all kinds of political theory going forward.
Fresh evidence relating the great Adriatic surge of 21 June 1978 to mesoscale atmospheric forcing
Authors: Orlić Mirko , Belušić Danijel , Janeković Ivica , Pasarić Miroslava
Published: June 2010

On the morning of 21 June 1978, exceptional sea level oscillations with a trough‐to‐crest height of 6 m and a period of 10–20 min were observed in Vela Luka Bay. Slightly less pronounced variability was observed in a wider middle and south Adriatic east coastal area and, with some delay, along the west coast. In this paper, one of the original hypotheses put forward to interpret the event, relating it to a mesoscale air pressure disturbance, is reconsidered by using all the available data as well as state‐of‐the‐art meteorological and oceanographic models. A fresh look at the meteorological data confirms that the atmospheric disturbance propagated at about 22 m/s in a northeastward direction. Additionally, the data suggest that it had the shape of the boxcar function characterized by an air pressure offset of 3 mbar and duration of 10 min. The meteorological model employed (Weather Research and Forecasting (WRF)‐Advanced Research WRF) proves unable to reproduce the mesoscale disturbance coinciding with the surge, but it shows that the background atmospheric conditions were favorable for the development of such disturbances. The oceanographic model Advanced Circulation Model for Shelves, Coasts and Estuaries (two‐dimensional depth integrated), forced by the described air pressure disturbance, successfully reproduces sea level variability in Vela Luka Bay reaching a few meters and thus surpassing the inverted barometer response by two orders of magnitude. The enhancement appears to be due to a four‐phase process. The model also suggests that the scattering due to the variable bathymetry and the reflection from the east Adriatic coast resulted in waves that returned towards the west coast and generated considerable sea level activity there.
Return stroke peak current versus charge transfer in rocket‐triggered lightning
Authors: Schoene J. , Uman M. A. , Rakov V. A.
Published: June 2010

We examined data on 117 return strokes in 31 rocket‐and‐wire‐triggered lightning flashes acquired during experiments conducted from 1999 through 2004 at the International Center for Lightning Research and Testing at Camp Blanding, Florida, in order to compare the peak currents of the lightning return strokes with the corresponding charges transferred during various time intervals within 1 ms after return stroke initiation. We find that the determination coefficient (R2) for lightning return stroke peak current versus the corresponding charge transfer decreases with increasing the duration of the charge transfer starting from return stroke onset. For example, R2 = 0.91 for a charge transfer duration of 50 μs after return stroke onset, R2 = 0.83 for a charge transfer duration of 400 μs, and R2 = 0.77 for a charge transfer duration of 1 ms. Our results support the view that (1) the charge deposited on the lower portion of the leader channel determines the current peak and that (2) the charge transferred at later times is increasingly unrelated to both the current peak and the charge deposited on the lower channel section. Additionally, we find that the relation between triggered‐lightning peak current and charge transfer to 50 μs in Florida is essentially the same as that for subsequent strokes in natural lightning in Switzerland, further confirming the view that triggered‐lightning strokes are very similar to subsequent strokes in natural lightning.
PSInSAR as a new tool to monitor pre‐eruptive volcano ground deformation: Validation using GPS measurements on Piton de la Fournaise
Authors: Peltier A. , Bianchi M. , Kaminski E. , Komorowski J.‐C. , Rucci A. , Staudacher T.
Published: June 2010

The Permanent Scatterers Synthetic Aperture Radar Interferometry (PSInSAR™) is a technique, which aims at ground deformation mapping with millimetric precision. In the framework of the Globvolcano ESA project, we evaluated a PSInSAR derived approach to monitor ground deformation in highly active volcanic areas, based on the example of Piton de La Fournaise. The Permanent Scatterer (PS) velocities show two main areas of deformation: (1) the eastern flank displaying old lava flow subsidence (0.05–0.13 m.y−1); and (2) the summit cone highly disturbed by eruptions. The PS time series for the summit area agree with the cGPS trends with small long‐term (weeks/months) ground displacements preceding eruptions (0.05–0.35 m.y−1) and large rapid ground displacements linked to eruptions. Despite some limitations, such as the loss of coherence during the most rapid ground displacements and lava flow emplacement, PSInSAR and its derived approach provide a reliable inference of the volcano ground deformation over large areas.
Obesity and Persistent Organic Pollutants: Possible Obesogenic Effect of Organochlorine Pesticides and Polychlorinated Biphenyls
Authors: Dirinck Eveline , Jorens Philippe G. , Covaci Adrian , Geens Tinne , Roosens Laurence , Neels Hugo , Mertens Ilse , van Gaal Luc
Published: June 2010

Persistent organic pollutants (POPs) are endocrine‐disrupting chemicals associated with the development of the metabolic syndrome and type 2 diabetes. In humans, little is known about their role in the potential origin of obesity. This study aims to assess the associations between serum levels of POPs and the prevalence of obesity in a cohort of obese and lean adult men and women. POP serum samples were investigated cross‐sectionally in 98 obese and 47 lean participants, aged ≥18 years. Serum samples were analyzed for the presence of polychlorinated biphenyl (PCB) congeners 153, 138, 180, and 170 and for the organochlorine pesticides, dichloro‐diphenyl‐dichloroethylene (pp‐DDE), and β‐hexachlorocyclohexane (βHCH). We established a significant negative correlation between BMI, waist, fat mass percentage, total and subcutaneous abdominal adipose tissue, and serum levels of PCB 153, 180, 170, and the sumPCBs. For βHCH, we demonstrated a positive correlation with BMI, waist, fat mass percentage, and total and subcutaneous abdominal adipose tissue. PCBs 180, 170, and the sum of PCBs correlated significantly negative with homeostasis model assessment for insulin resistance (HOMAIR). βHCH correlated significantly positively with HOMAIR. A strong correlation was established between all POP serum levels and age. We established a positive relationship between high serum levels of βHCH and BMI and HOMAIR, whereas serum PCB levels were inversely correlated with BMI and HOMAIR. Combined, these results suggest that the diabetogenic effect of low‐dose exposure to POPs might be more complicated than a simple obesogenic effect.
Effects of Exendin‐4 Alone and With Peptide YY3–36 on Food Intake and Body Weight in Diet‐Induced Obese Rats
Authors: Reidelberger Roger D. , Haver Alvin C. , Apenteng Bettye A. , Anders Krista L. , Steenson Sharalyn M.
Published: June 2010

Significant weight loss following Roux‐en‐Y gastric bypass surgery (RYGB) in obese humans correlates with enhanced secretion of anorexigenic gut hormones glucagon‐like peptide‐1 (GLP‐1) and peptide YY3–36 (PYY3–36). Our aim here was to identify a dosing strategy for intraperitoneal (IP) infusion of GLP‐1 homologue exendin‐4 alone and with PYY3–36 that produces a sustained reduction in daily food intake and body weight in diet‐induced obese (DIO) rats. We tested 12 exendin‐4 strategies over 10 weeks. Exendin‐4 infused during the first and last 3 h of the dark period at 15–20 pmol/h (0.15 nmol/kg/day) produced a sustained 24 ± 1% reduction in daily food intake for 17 days, and decreased body weight by 7%. In a separate group of DIO rats, none of seven dosing strategies combining exendin‐4 and PYY3–36 produced a similar reduction in daily food intake for >10 days. The subsequent decline in efficacies of exendin‐4 alone and with PYY3–36 on food intake and body weight in each experiment suggested possible receptor downregulation and tolerance to treatments. However, when treatments were discontinued for 1 day following losses in efficacies, daily food intake significantly increased. Together, these results demonstrate that (i) intermittent IP infusion of a low dose of exendin‐4 can produce a relatively prolonged reduction in daily food intake and body weight in DIO rats, (ii) co‐infusion of exendin‐4 and PYY3–36 does not further prolong this response, and (iii) activation of an orexigenic mechanism gradually occurs to counteract the inhibitory effects of exendin‐4 alone and with PYY3–36 on food intake and body weight.
Reversal of Small, Dense LDL Subclass Phenotype by Weight Loss Is Associated With Impaired Fat Oxidation
Authors: Siri‐Tarino Patty W. , Woods Amy C. , Bray George A. , Krauss Ronald M.
Published: June 2010

Adiposity is more prevalent among individuals with a predominance of small, dense low‐density lipoprotein (LDL) (pattern B) particles than among those with larger LDL (pattern A). We tested for differences in resting energy expenditure (REE) and respiratory quotient (RQ) in overweight men with pattern A (n = 36) or pattern B (n = 60). Men consumed a standardized isoenergetic diet for 3 weeks after which a ∼9 kg weight loss was induced by caloric deficit for 9 weeks, followed by 4 weeks of weight stabilization. REE and RQ were measured by indirect calorimetry before and after weight loss. Results were analyzed separately in pattern B men who converted to pattern A (B→A; n = 35) and those who did not (B→B; n = 25). At baseline, B→B men had higher trunk fat, triacylglycerol (TG) and insulin concentrations, homeostasis model assessment of insulin resistance (HOMAIR), and smaller LDL particles compared to B→A men and baseline pattern A men who remained pattern A (A→A; n = 35). REE normalized to fat‐free mass did not change after weight loss. RQ decreased in A→A men, increased in B→A men, and did not change significantly in B→B men after weight loss. Calculated fat oxidation rates paralleled the RQ results. Baseline plasma TG concentrations were positively correlated with RQ and inversely correlated with the magnitude of weight loss achieved for a given prescribed energy reduction in the entire study population. Pattern B men who converted to pattern A with weight loss may have an underlying impairment in fat oxidation that predisposes to both dyslipidemia and an impaired ability to achieve weight loss by energy restriction.
The Relationship Between Visceral Adiposity and the Risk of Erosive Esophagitis in Severely Obese Chinese Patients
Authors: Tai Chi‐Ming , Lee Yi‐Chia , Tu Hung‐Pin , Huang Chih‐Kun , Wu Ming‐Tin , Chang Chi‐Yang , Lee Ching‐Tai , Wu Ming‐Shiang , Lin Jaw‐Town , Wang Wen‐Ming
Published: June 2010

A higher prevalence of erosive esophagitis is found in obese than in nonobese patients; however, it remains unclear why some obese patients develop this disease, whereas others do not. Accordingly, we elucidated the risk factors associated with erosive esophagitis in severely obese Chinese patients. Between June 2007 and January 2009, a total of 260 Chinese patients with morbid obesity referred for bariatric surgery were enrolled in this cross‐sectional study. All patients received preoperative endoscopy for evaluation of the presence and severity of erosive esophagitis. Demographic variables, anthropometric measurements, and metabolic factors were included in a logistic regression model to identify the factors predictive of erosive esophagitis. The prevalence of erosive esophagitis was 32.3%. Multiple logistic regression showed that increased waist circumference (odds ratio (OR) = 1.03, 95% confidence interval (CI) = 1.01–1.04), increased insulin resistance (OR = 1.57, 95% CI = 1.06–2.31), and presence of reflux symptoms (OR = 2.40, 95% CI = 1.22–4.74) were independent risk factors associated with erosive esophagitis. In conclusion, among Chinese patients with morbid obesity, increased waist circumference and insulin resistance were risk factors for erosive esophagitis, which highlights the critical role of visceral adiposity in the pathogenesis of erosive esophagitis.
Revisiting Bergmann's rule for saguaros (Carnegiea gigantea (Engelm.) Britt. and Rose): stem diameter patterns over space
Authors: Drezner Taly Dawn
Published: June 2010

Aim The influence of winter temperatures and other climate variables are explored to determine which variables are associated with saguaro stem diameter and to determine if Bergmann's rule is applicable to saguaros.

Location The northern Sonoran Desert in Arizona, USA.

Methods Thirty saguaro populations were sampled (height, diameter, number of branches), and after adjustment for population height structure, mean relative thickness of saguaros was calculated for each plot (population). Fifty‐seven climate variables were calculated for the thirty populations. Regression was run to determine which variables (cold winter, hot summer and precipitation) best predict relative thickness. Previous studies have demonstrated a significant positive relationship between winter precipitation and saguaro branching (Drezner, 2003, Ecography, in press). To determine if relative thickness may be an artefact of branching (branches), partial correlation analysis was employed.

Results Mean March precipitation best predicts relative thickness. When only winter temperature variables are considered, none are significantly related to relative thickness. Relative thickness is not an artefact of branches.

Main conclusions  (1) Rainfall, not temperature, best predicts saguaro stem thickness. In addition, despite the focus on summer rains in the literature, winter precipitation is the best predictor of thickness. (2) Bergmann's rule is not applicable to saguaro populations as has been previously suggested [e.g. Niering et al. (1963)Science142, 15], as thickness does not increase significantly with latitude. In addition, the suggested mechanism for Bergmann's rule, cold winter temperature, does not significantly predict saguaro stem diameters over the area studied. In some populations that experience high winter rainfall as well as cold temperatures, individuals likely derive thermal benefits from a larger stem diameter; however, the trend is not observed over the area studied and it does not appear to be adaptive.
Exotic plant species of the St Lawrence River wetlands: a spatial and historical analysis
Authors: Lavoie Claude , Jean Martin , Delisle Fanny , Létourneau Guy
Published: June 2010

Aim To evaluate the importance (number of species, plant cover) of the exotic flora in seven well‐defined sectors of one of the most important transportation waterways in North America. To determine the impact of exotic species on wetland plant diversity and reconstruct the spread of some invasive species.

Location St Lawrence River, southern Québec.

Methods The exotic flora (vascular plants) of wetlands bordering the St Lawrence River was studied using 713 sampling stations (25 m2) along a 560‐km long corridor.

Results Exotic species represent 13.7% of the vascular flora of the St Lawrence wetlands. The relative plant cover occupied by exotic species is high in some of the fluvial sectors (42–44%), but low (6–10%) in the estuarine sectors. Wetlands (marshes) surrounding islands were particularly susceptible to invasion by exotic plants. Historical, abiotic and landscape factors may explain the differences observed between sites. Purple loosestrife (Lythrum salicariaL.) is the most common exotic species of the St Lawrence wetlands, but other species, namely flowering‐rush (Butomus umbellatusL.) and reed canary grass (Phalaris arundinaceaL.) are much more invasive. There is no linear relationship between the exotic species cover and the diversity of wetland plants; low diversity sites can be dominated by either exotic or native plant species. In the other sites, exotic species generally have little impact on plant communities and can contribute to increase diversity. Common reed (Phragmites australis(Cav.) Trin. ex Steudel) and reed canary grass, both considered as exotic species in this study, clearly have a stronger impact on plant diversity than flowering‐rush and purple loosestrife.

Main conclusions This study shows that the global impact of an invader cannot be adequately evaluated with only a few highly invaded sites. While nationwide strategies have been developed to control exotic species, large surveys are essential to adapt them to regional particularities.
Real vs. artefactual absences in species distributions: tests for Oryzomys albigularis (Rodentia: Muridae) in Venezuela
Authors: Anderson Robert P.
Published: June 2010

Aim  Numerous geographical information system (GIS)‐based techniques for estimating a species’ potential geographical distribution now exist. While a species’ potential distribution is more extensive than its documented range, the lack of records from some suitable regions may simply derive from inadequate sampling there. Using occurrence records of both the study species and the more inclusive overall target group, I propose a progression of statistical models to evaluate apparent absences in species distributions.

Location  Northern Venezuela.

Methods  Employing data from the Smithsonian Venezuelan Project (a large set of standardized mammalian inventories undertaken across Venezuela), I tested distributional hypotheses for the sigmodontine rodent Oryzomys albigularis (Tomes, 1860). Those inventories collected O. albigularis in two of the five major montane regions of northern Venezuela (the Cordillera de Mérida/Macizo de El Tamá and Cordillera de la Costa Central). I used the Genetic Algorithm for Rule‐Set Prediction (GARP) to estimate the species’ potential distribution in northern Venezuela. Then, based on all collection localities from the Smithsonian Venezuelan Project, I determined the probability that the absence of O. albigularis from the three regions of potential presence where it was not documented (the Serranía de Perijá, Lara–Falcón highlands, and Cordillera de la Costa Oriental) could be the result of inadequate sampling.

Results and main conclusions  All statistical models indicated that the sampling efforts of the Smithsonian Venezuelan Project were insufficient to demonstrate conclusively the absence of O. albigularis from any of the three regions lacking records. Indeed, a subsequent compilation of specimens from ten natural history museums confirmed its presence in the Serranía de Perijá and the Lara–Falcón highlands. Tests using empirical sampling effort and taking human modification of the landscape into account most closely fulfilled the assumptions required for the tests. By providing a framework for bringing additional quantitative rigour to studies of species distributions, these methods will probably prove of wide applicability to other systems.
Effects of forest fragmentation on European birds: implications of regional differences in species richness
Authors: Tellería José Luis , Baquero Rocío , Santos Tomás
Published: June 2010

Aim In this paper, we adopted a large‐scale approach to evaluate the effect of regional richness of forest birds on the number of bird species retained by forest fragments in several localities across Europe.

Location We studied bird assemblages in fourteen forest archipelagos embedded in agricultural matrices from southern Norway to central Spain. Tree composition varied from oak and beech forests of the northern localities to oak and pine xerophitic woodlands of the southern ones. The number of fragments in each forest archipelago ranged from eighteen to 211.

Methods We used the Gleason equation (s = a + z  log  A; wheresandAare, respectively, the species richness and size of forest fragments andzthe rate of species loss) to estimate the species richness for 1‐ and 15‐ha fragments in each archipelago. The regional richness of forest birds was estimated by modelling the geographical distribution of species richness in the European atlas of breeding birds.

Results The latitudinal distribution of regional richness displayed a convex form, with the highest values being in central Europe. Along this gradient, the number of species retained by fragments and the rate of species loss was positively related to regional richness. In addition, the percentage of the regional pool of species sampled by fragments decreased in the southern localities.

Main conclusions Relationships between regional richness of forest birds and richness in fragments seem to explain why fragments in central Europe shelter more species than their southern counterparts. The decreased ability of southern forest fragments to sample the regional richness of forest birds, could be explained as an effect of the low abundance of many species in the Mediterranean, which could depress their ability to prevent extinction in fragments by a rescue effect. Alternatively, high beta diversity in the Mediterranean could produce undersampling by fragments of the regional pool of species. These regional differences in the response of bird assemblages to forest fragmentation are used to discuss the usefulness of large‐scale, biogeographical approaches in the design of conservation guidelines.
Representation of tundra vegetation by pollen in lake sediments of northern Alaska
Authors: Wyatt Oswald W. , Anderson Patricia M. , Brubaker Linda B. , Hu Feng Sheng , Engstrom Daniel R.
Published: June 2010

Aim  To understand better the representation of arctic tundra vegetation by pollen data, we analysed pollen assemblages and pollen accumulation rates (PARs) in the surface sediments of lakes.

Location  Modern sediment samples were collected from seventy‐eight lakes located in the Arctic Foothills and Arctic Coastal Plain regions of northern Alaska.

Methods  For seventy of the lakes, we analysed pollen and spores in the upper 2 cm of the sediment and calculated the relative abundance of each taxon (pollen percentages). For eleven of the lakes, we used 210Pb analysis to determine sediment accumulation rates, and analysed pollen in the upper 10–15 cm of the sediment to estimate modern PARs. Using a detailed land‐cover map of northern Alaska, we assigned each study site to one of five tundra types: moist dwarf‐shrub tussock‐graminoid tundra (DST), moist graminoid prostrate‐shrub tundra (PST) (coastal and inland types), low‐shrub tundra (LST) and wet graminoid tundra (WGT).

Results  Mapped pollen percentages and multivariate comparison of the pollen data using discriminant analysis show that pollen assemblages vary along the main north–south vegetational and climatic gradients. On the Arctic Coastal Plain where climate is cold and dry, graminoid‐dominated PST and WGT sites were characterized by high percentages of Cyperaceae and Poaceae pollen. In the Arctic Foothills where climate is warmer and wetter, shrub‐dominated DST, PST and LST were characterized by high percentages of Alnus and Betula pollen. Small‐scale variations in tundra vegetation related to edaphic variability are also represented by the pollen data. Discriminant analysis demonstrated that DST sites could be distinguished from foothills PST sites based on their higher percentages of Ericales and Rubus chamaemorus pollen, and coastal PST sites could be distinguished from WGT sites based on their higher percentages of Artemisia. PARs appear to reflect variations in overall vegetation cover, although the small number of samples limits our understanding of these patterns. For coastal sites, PARs were higher for PST than WGT, whereas in the Arctic Foothills, PARs were highest in LST, intermediate in DST, and lowest in PST.

Main conclusion  Modern pollen data from northern Alaska reflect patterns of tundra vegetation related to both regional‐scale climatic gradients and landscape‐scale edaphic heterogeneity.