bluuebunny/crossref_metadata_2025 huggingface dataset:
Edge effects in recruitment of trees, and relationship to seed dispersal patterns, in cleared strips in the Peruvian Amazon
Authors: Gorchov David L. , Rondon Xanic J. , Cornejo Fernando , Schaefer Robert L. , Janosko Julia M. , Slutz Greg
Published: November 2012

We investigated the spatial pattern of tree recruitment 15 years after clear‐cutting in two logged strips in the Peruvian Amazon, focusing on differences between seed dispersal modes and cohorts, and relating these to spatial patterns of seed dispersal in the years immediately following clearing. Most trees that recruited in logged strips belonged to taxa dispersed by birds or nonvolant mammals, with smaller numbers dispersed by bats or wind. Seed dispersal patterns differed, with few mammal‐dispersed seeds reaching strips, bird‐dispersed seeds more abundant near the forest edge than strip centers, and bat‐ and wind‐dispersed seeds more evenly distributed. However, this pattern was not reflected in the tree recruits, except in the deferment cut half of strip 2. Different dispersal modes were differentially represented in different cohorts; for example, in strip 1 bird‐dispersed trees predominated in early cohorts, while trees dispersed by nonvolant mammals predominated in later cohorts. Our finding that trees dispersed by mammals (which disperse the majority of commercial trees in Amazonia) successfully regenerate from seed in the interior of logged strips highlights the value of maintaining these animals in forest management systems.
Analysis of CLA Isomer Distribution in Nutritional Supplements by Single Column Silver‐Ion HPLC
Authors: Cossignani L. , Giua L. , Lombardi G. , Simonetti M. S. , Damiani P. , Blasi F.
Published: November 2012

Nutritional supplements containing conjugated linoleic acid (CLA) isomers, widely used to improve body composition and inhibit fat storage, should be thoroughly analyzed, as CLA effects are isomer specific. In this research, an improvement of silver‐ion high performance liquid chromatography (Ag+‐HPLC) was obtained by using a single‐column instead of the most commonly used multi‐columns. To develop the procedure, a standard CLA mixture has been derivatized with different chain length alcohols (from methanol to hexanol). Hexyl CLA showed better separation between CLA isomer pairs, in particular the resolution of the t10,c12: c9,t11 pair increased from 0.3 (methyl esters) to 0.8 (hexyl esters). Therefore, the CLA isomer composition of some commercial CLA products was determined by Ag+‐HPLC analysis of hexyl esters. The main isomers in all supplements turned out to be c9,t11‐CLA and t10,c12‐CLA, the most anti‐adipogenic isomer. t8,c10‐ and c11,t13‐CLA were not detected. The nutritional supplements were also analyzed by high resolution gas chromatography of methyl esters to evaluate the fatty acid % composition and total CLA % content. The total CLA ranged from 79.4 to 94.4 %, and the t,t isomer from 1.4 to 7.3 %.
Simplex‐Centroid Mixture Design Applied to the Aqueous Enzymatic Extraction of Fatty Acid‐Balanced Oil from Mixed Seeds
Authors: Li Yang , Zhang Yan , Wang Mei , Jiang Lianzhou , Sui Xiaonan
Published: November 2012

A one‐step method was developed to extract oil from a mixture of soybeans, peanuts, linseeds, and tea seeds using an aqueous enzymatic method. The proportion of the four seeds was targeted in accordance with a fatty acid ratio of 0.27 (SFA, saturated fatty acid(s)): 1 (MUFA, monounsaturated fatty acid(s)): 1 (PUFA, polyunsaturated fatty acid(s)), and the oil extraction yield was maximized by applying the simplex‐centroid mixture design method. Three models were developed for describing the relationship between the proportion of the individual seeds in the mixture, the fatty acid ratio in the extracted oil, and the oil extraction yield, respectively. The developed models were then analyzed using an ANOVA and were found to fit the data quite well, with R2 values of 0.98, 0.93, and 0.93, respectively. The three models were validated experimentally. The results indicated that the ratio of fatty acids in the oil ranged between 0.98 and 1.12 (MUFA:PUFA) and between 0.26 and 0.28 (SFA:MUFA), which were quite close to the target values of 1 and 0.27, respectively. The oil extraction yield of 62.13 % was slightly higher than the predicted value (60.32 %).
Portuguese text generation using factored language models
Authors: de Novais Eder Miranda , Paraboni Ivandré
Published: November 2012

As in many other natural language processing (NLP) fields, the use of statistical methods is now part of mainstream natural language generation (NLG). In the development of systems of this kind, however, there is the issue of data sparseness, a problem that is particularly evident in the case of morphologically-rich languages such as Portuguese. This work presents a shallow surface realisation system that makes use of factored language models (FLMs) of Portuguese to overcome some of these difficulties. The system combines FLMs trained on a large corpus with a number of NLP resources that have been made publicly available by the Brazilian NLP research community in recent years, such as corpora, dictionaries, thesauri and others. Our FLM-based approach to surface realisation has been successfully applied to the generation of Brazilian newspapers headlines, and the results are shown to outperform a number of statistical and non-statistical baseline systems alike.
Physical measures and absolute continuity for one-dimensional center direction
Authors: Viana Marcelo , Yang Jiagang
Published: November 2012

For a class of partially hyperbolic

C^{k}

,

k > 1

diffeomorphisms with circle center leaves we prove the existence and finiteness of physical (or Sinai–Ruelle–Bowen) measures, whose basins cover a full Lebesgue measure subset of the ambient manifold. Our conditions hold for an open and dense subset of all

C^{k}

partially hyperbolic skew-products on compact circle bundles.

Our arguments blend ideas from the theory of Gibbs states for diffeomorphisms with mostly contracting center direction together with recent progress in the theory of cocycles over hyperbolic systems that call into play geometric properties of invariant foliations such as absolute continuity. Recent results show that absolute continuity of the center foliation is often a rigid property among volume preserving systems. We prove that this is not at all the case in the dissipative setting, where absolute continuity can even be robust.
Moderating effect of schizotypy on the relationship between smoking and neurocognition
Authors: Hori H. , Matsuo J. , Teraishi T. , Sasayama D. , Kawamoto Y. , Kinoshita Y. , Ota M. , Hattori K. , Kunugi H.
Published: November 2012

Purpose

Smoking rates in schizotypic individuals are shown to be elevated, as in patients with schizophrenia, although findings on the association of smoking with different symptomatology of schizotypy have been mixed. Moreover, possible moderating effects of schizotypy on the relationship between smoking and cognition have not been well documented.

Subjects and methods

The Schizotypal Personality Questionnaire (SPQ) and the full version of the Wechsler Memory Scale-Revised (WMS-R) were administered to 501 healthy adults. Subjects were divided into smokers (n = 85) and non-smokers (n = 416) based on the presence/absence of current smoking.

Results

The analysis of covariance (ANCOVA) on the three factor scores as well as the total score of the SPQ, controlling for age and gender, revealed that cognitive-perceptual factor was significantly associated with an increased rate of smoking (P = 0.048). The ANCOVA on the WMS-R indices, with smoking group as a fixed factor and age, gender and total SPQ score as covariates, revealed that the schizotypy-by-smoking interaction was significant for attention/working memory (P = 0.029).

Discussion and conclusion

Positive schizotypy may be associated with more smoking. Schizotypy and smoking could interact with each other to negatively affect attention/working memory.
Detecting single photons: A supramolecular matter?
Authors: Cangiano Lorenzo , Dell'Orco Daniele
Published: November 2012

Rod photoreceptors detect single photons through a tradeoff of light collecting ability, amplification and speed. Key roles are played by rhodopsin (Rh) and transducin (G
t
), whose complex supramolecular organization in outer segment disks begs for a functional interpretation. Here we review past and recent evidence of a temperature‐dependence of photon detection by mammalian rods, and link this phenomenon with the putative oligomeric organization of Rh and new ideas on the dynamics of Rh–G
t
interaction. Identifying an electrophysiological correlate of the supramolecular organization of Rh and G
t
may shed light on the evolutionary advantage it confers to night vision.
Running‐induced epigenetic and gene expression changes in the adolescent brain
Authors: Abel Jean LeBeau , Rissman Emilie F.
Published: November 2012

Physical exercise is associated with positive neural functioning. Here we examined the gene expression consequences of 1 week of voluntary wheel running in adolescent male mice. We assayed expression levels of genes associated with synaptic plasticity, signaling pathways, and epigenetic modifying enzymes. Two regions were examined: the hippocampus, which is typically examined in exercise studies, and the cerebellum, an area directly involved in motor control and learning. After 1 week of exercise, global acetylation of histone 3 was increased in both brain regions. Interestingly this was correlated with increased brain derived neural growth factor in the hippocampus, as noted in many other studies, but only a trend was found in cerebellum. Differences and similarities between the two areas were noted for genes encoding functional proteins.

In contrast, the expression pattern of DNA methyltransferases (Dnmts) and histone deacetylases (Hdacs), genes that influence DNA methylation and histone modifications in general, decreased in both regions with exercise. We hypothesize that epigenetic mechanisms, involving many of the genes assessed here, are essential for the positive affects of exercise on behavior and suspect these data have relevance for adolescent boys.
Long‐term anticholinergic use and the aging brain
Authors: Cai Xueya , Campbell Noll , Khan Babar , Callahan Christopher , Boustani Malaz
Published: November 2012

Background

Older Americans are facing an epidemic of chronic diseases and are thus exposed to anticholinergics (ACs) that might negatively affect their risk of developing mild cognitive impairment (MCI) or dementia.

Objective

To investigate the association between impairment in cognitive function and previous AC exposure.

Design

A retrospective cohort study.

Setting

Primary care clinics in Indianapolis, Indiana.

Participants

A total of 3690 older adults who have undergone cognitive assessment and had a 1‐year medication‐dispensing record.

Outcome

Cognitive function was measured in two sequential steps: a two‐step screening process followed by a formal diagnostic process for participants with positive screening results.

Exposure

Three patterns of AC exposure were defined by the duration of AC exposure, the number of AC medications dispensed at the same time, and the severity of AC effects as determined by the Anticholinergic Cognitive Burden list.

Results

Compared with older adults with no AC exposure and after adjusting for age, race, gender, and underlying comorbidity, the odds ratio for having a diagnosis of MCI was 2.73 (95% confidence interval, 1.27–5.87) among older adults who were exposed to at least three possible ACs for at least 90 days; the odds ratio for having dementia was 0.43 (95% confidence interval, 0.10–1.81).

Conclusion

Exposure to medications with severe AC cognitive burden may be a risk factor for developing MCI.
Late Pleistocene vegetation change in Korea and its possible link to East Asian monsoon and Dansgaard–Oeschger (D–O) cycles
Authors: Lim Jaesoo , Kim Ju-Yong , Kim Seon-Ju , Lee Jin-Young , Hong Sei-Sun
Published: November 2012

Late Pleistocene carbon isotope (δ13C) records from a paleolithic sedimentary sequence collected from Baeki, Hongcheon, central Korea, show long-term changes with superimposed short-term isotopic excursions. The δ13C value of the sedimentary organic matter, a proxy for past vegetation change, varied from − 26‰ to − 23‰ for the period between 30 and 90 ka, with a long-term variation similar to insolation changes. High-amplitude (− 1‰ to approximately − 1.5‰) fluctuations superimposed on the long-term changes in the δ13C values decreased during stronger summer monsoon intervals but increased during the weakened summer monsoon. This millennial-scale pattern is generally similar to Greenland Dansgaard–Oeschger (D–O) cycles. The possible connection between the Hongcheon area, Korea and high latitudes may be explained by atmospheric circulation changing in response to the D–O oscillations in the Northern Hemisphere.
Australia in the Global Economy
Authors: Dyster Barrie , Meredith David
Published: November 2012

With the global economy in crisis, there is great need for a deeper understanding of Australia's economic place in the world – both today and throughout history. This new edition of Barrie Dyster and David Meredith's highly successful book is fully updated and includes three new chapters covering until the end of 2011. The book explores the evolution of Australia's position in the global economy from the start of the twentieth century through to the present day, examining the international and local economies of five key historical periods. With a focus on trade, foreign investment and immigration, the book considers periods both of growth and decline. By using historical perspectives to explain the present and give direction to the future, this unique book presents a rich account of Australia's position within a global economic context. It is an essential resource for students and lecturers of Australian economic history.
Essentials of EU Law
Authors: Reinisch August
Published: November 2012

Students new to the study of EU law can find knowing what questions to ask to be as much of a challenge as answering them. This book clearly sets the scene: it explores the history and institutions of the EU, examines the interplay of its main bodies in its legislative process and illustrates the role played by the EU Courts and the importance of fundamental rights. The student is also introduced to the key principles of the internal market, in particular the free movement of goods and the free movement of workers. In addition a number of other EU policies, such as the Common Agricultural Policy, Environmental Protection and Social Policy are outlined, while a more detailed inquiry is made into European competition law. This book is an essential first port-of-call for all students of European law.
Short Introduction to Strategic Human Resource Management
Authors: Cascio Wayne F. , Boudreau John W.
Published: November 2012

This Short Introduction to Strategic Human Resource Management provides a concise treatment of the key elements of strategic HRM using an innovative risk-management approach. It emphasizes the importance of the decisions, processes and choices organizations make about managing people and shows how workforce management directly affects strategic organizational outcomes. It provides guidance for managers on how to make better human capital decisions in order to achieve strategic success more effectively. Reflecting an increasing uncertainty in global business, Cascio and Boudreau consider ways of dealing with risk in managing human capital. Numerous examples in every chapter illustrate key points with real business cases from around the world.
Are We Getting Smarter?
Authors: Flynn James R.
Published: November 2012

The 'Flynn effect' is a surprising finding, identified by James R. Flynn, that IQ test scores have significantly increased from one generation to the next over the past century. Flynn now brings us an exciting new book which aims to make sense of this rise in IQ scores and considers what this tells us about our intelligence, our minds and society. Are We Getting Smarter? features fascinating new material on a variety of topics including the effects of intelligence in the developing world; the impact of rising IQ scores on the death penalty, cognitive ability in old age and the language abilities of youth culture; as well as controversial topics of race and gender. He ends with the message that assessing IQ goes astray if society is ignored. As IQ scores continue to rise into the twenty-first century, particularly in the developing world, the 'Flynn effect' marches on.
Representations of Lie Algebras
Authors: Henderson Anthony
Published: November 2012

This bold and refreshing approach to Lie algebras assumes only modest prerequisites (linear algebra up to the Jordan canonical form and a basic familiarity with groups and rings), yet it reaches a major result in representation theory: the highest-weight classification of irreducible modules of the general linear Lie algebra. The author's exposition is focused on this goal rather than aiming at the widest generality and emphasis is placed on explicit calculations with bases and matrices. The book begins with a motivating chapter explaining the context and relevance of Lie algebras and their representations and concludes with a guide to further reading. Numerous examples and exercises with full solutions are included. Based on the author's own introductory course on Lie algebras, this book has been thoroughly road-tested by advanced undergraduate and beginning graduate students and it is also suited to individual readers wanting an introduction to this important area of mathematics.
The Sources of Social Power
Authors: Mann Michael
Published: November 2012

Distinguishing four sources of power - ideological, economic, military and political - this series traces their interrelations throughout human history. This third volume of Michael Mann's analytical history of social power begins with nineteenth-century global empires and continues with a global history of the twentieth century up to 1945. Mann focuses on the interrelated development of capitalism, nation-states and empires. Volume 3 discusses the 'Great Divergence' between the fortunes of the West and the rest of the world; the self-destruction of European and Japanese power in two world wars; the Great Depression; the rise of American and Soviet power; the rivalry between capitalism, socialism and fascism; and the triumph of a reformed and democratic capitalism.
The Limits of Altruism in Democratic Athens
Authors: Christ Matthew
Published: November 2012

Athenians in the classical period (508–322 BC) were drawn to an image of themselves as a compassionate and generous people who rushed to the aid of others in distress, both at home and abroad. What relation does this image bear to actual Athenian behavior? This book argues that Athenians felt little pressure as individuals to help fellow citizens whom they did not know. Democratic ideology called on citizens to refrain from harming one another rather than to engage in mutual support, and emphasized the importance of the helping relationship between citizen and city rather than among individual citizens. If the obligation of Athenians to help fellow citizens was fairly tenuous, all the more so was their responsibility to intervene to assist the peoples of other states; a distinct pragmatism prevailed in the city's decisions concerning intervention abroad.
Doing Capitalism in the Innovation Economy
Authors: Janeway William H.
Published: November 2012

The innovation economy begins with discovery and culminates in speculation. Over some 250 years, economic growth has been driven by successive processes of trial and error: upstream exercises in research and invention and downstream experiments in exploiting the new economic space opened by innovation. Drawing on his professional experiences, William H. Janeway provides an accessible pathway for readers to appreciate the dynamics of the innovation economy. He combines personal reflections from a career spanning forty years in venture capital, with the development of an original theory of the role of asset bubbles in financing technological innovation and of the role of the state in playing an enabling role in the innovation process. Today, with the state frozen as an economic actor and access to the public equity markets only open to a minority, the innovation economy is stalled; learning the lessons from this book will contribute to its renewal.
Couple and Family Therapy with Five Physical Rehabilitation Populations: A Scoping Review
Authors: Allan Robert , Ungar Michael
Published: November 2012

This article provides a scoping review with a focus on the substantive and methodological issues of the research pertaining to couple and family therapy (CFT) with five physical medical rehabilitation populations. We searched for literature concerned with five populations: spinal cord injury, stroke, multiple sclerosis, traumatic brain injury and amputations. A detailed review of CINAHL, PubMed, and PsycINFO databases identified 14 publications that researched couple/family therapy interventions with these populations. We synthesised the data by outlining and charting the substantive and methodological issues with this research. Findings suggest that individuals who have sustained an injury or are diagnosed with an illness requiring extensive rehabilitation experience increased relationship distress and decreased family functioning. While the literature clearly points to the impact on spouses and families, CFT was primarily used to engage families in efforts to assist health care workers improve physical functioning.
Efficacy of a Character Strengths and Gratitude Intervention for People with Chronic Back Pain
Authors: Baxter Heidi J. , Johnson Malcolm H. , Bean Debbie
Published: November 2012

This study investigated the efficacy of a character strengths and gratitude intervention to reduce pain in people with chronic back pain. Eight participants (males = 4, females = 4) took part in a cross-over multi-baseline study over 5‒7 weeks. Comparisons were made for intervention efficacy effects by contrasting a character strengths approach with a comparison condition premised on positive memories. Daily measures were used to assess mood (happiness, sadness, anger) and pain. In addition, measures of happiness, depression, anxiety, pain catastrophising and pain were collected at each phase. The results indicated improved daily happiness and significantly reduced daily anger following the character strengths and gratitude intervention. This provides preliminary evidence that daily focusing on positive aspects of one's emotional experience benefits those with chronic back pain.
How phonetic features project more talk
Authors: Local John , Walker Gareth
Published: November 2012

Investigations into the management of turn-taking have typically focussed on pitch and other prosodic phenomena, particularly pitch-accents. Here, non-pitch phonetic features and their role in turn-taking are described. Through sustained phonetic and interactional analysis of a naturally occurring, 12-minute long telephone call between two adult speakers of British English, sets of talk-projecting and turn-projecting features are identified. Talk-projecting features include the avoidance of durational lengthening, articulatory anticipation, continuation of voicing, the production of talk in maximally close proximity to a preceding point of possible turn-completion, and the reduction of consonants and vowels. Turn-projecting features include the converse of each of the talk-projecting features, and two other distinct features: release of plosives at the point of possible turn-completion, and the production of audible outbreaths. We show that features of articulatory and phonatory quality and duration are relevant factors in the design and treatment of talk as talk- or turn-projective.
Bardi
Authors: Bowern Claire , McDonough Joyce , Kelliher Katherine
Published: November 2012

Bardi is the northernmost language of the Nyulnyulan family, a non-Pama-Nyungan family of the Western Kimberley region of northwestern Australia. Currently about five people speak the language fluently, but approximately 1,000 people identify as Bardi. The region was settled by Europeans in the 1880s and two missions were founded in Bardi country in the 1890s. Use of the language began declining in the 1930s. Many Bardi people were moved several times between 1940 and 1970, both to other missions dominated by speakers of other Indigenous languages and to local towns such as Derby. This community disruption accelerated the decline of language use in the community and first language acquisition. Bardi is the name of the language variety spoken at One Arm Point. There are two other named mutually intelligible varieties apart from Bardi: Baard and Jawi. The extent of dialect diversity within Bardi is unknown, but does not seem to have been particularly high compared to that between named varieties. The ISO-639 language code is [bcj].
Central Sama
Authors: Pallesen A. Kemp , Soderberg Craig
Published: November 2012

Central Sama (ISO code sml) is spoken in the Philippines throughout the Sulu Archipelago and the Sibuguey Gulf to the north, and in many scattered communities as far north as Manila Bay. In Sabah, Malaysia, it is spoken primarily in the districts of Semporna and Kunak. For more information regarding the classification of this language within Austronesian, see Gordon (2005).
Tausug (Suluk)
Authors: Soderberg Craig , Ashley Seymour A. , Olson Kenneth S.
Published: November 2012

Tausug (ISO code tsg) is an Austronesian language spoken on the island of Jolo in the southwestern Philippines. It is also found on other nearby islands in the southwestern part of the Philippines and in parts of Sabah, Malaysia, where it is called Suluk. The population of the Tausug in the Philippines is estimated at 900,000 (Gordon 2005) and the year 2000 population estimate of the Suluk in Sabah, Malaysia, is 150,000. The following description is based on the variety spoken on Jolo. ‘The North Wind and the Sun’ text was translated from English into Tausug by Irene Hassan. Previous studies of Tausug phonology include Asmah (1978, 1983) and Hassan, Ashley & Ashley (1994). David Lao, age 62 at the time of the recording, born in Jolo, Philippines, was the reader for the Tausug words in this article. Due to difficult access into the language area, all audio recordings were obtained by Skype transmission.
Is omniscience impossible?
Authors: PEELS RIK
Published: November 2012

In a recent paper, Dennis Whitcomb argues that omniscience is impossible. But if there cannot be any omniscient beings, then God, at least as traditionally conceived, does not exist. The objection is, roughly, that the thesis that there is an omniscient being, in conjunction with some principles about grounding, such as its transitivity and irreflexivity, entails a contradiction. Since each of these principles is highly plausible, divine omniscience has to go. In this article, I argue that Whitcomb's argument, if sound, has several unacceptable consequences. Among others, it implies that nobody knows that someone has knowledge, that, for most of us, all of our beliefs are false, and that there are no truths. This reductio all by itself provides sufficient reason to reject the argument. However, I also provide a diagnosis of where precisely the argument goes wrong. I argue that Whitcomb's crucial notion of grounding actually covers two distinct relations and that the principle of transitivity is true only for cases in which one of these relations holds rather than both of them.
The role of oxidative stress in postprandial endothelial dysfunction
Authors: Lacroix Sébastien , Rosiers Christine Des , Tardif Jean-Claude , Nigam Anil
Published: November 2012

Endothelial dysfunction is a turning point in the initiation and development of atherosclerosis and its complications and is predictive of future cardiovascular events. Ingestion of high-carbohydrate or high-fat meals often results in postprandial hyperglycaemia and/or hypertriacylglycerolaemia that may lead to a transient impairment in endothelial function. The present review will discuss human studies evaluating the impact of high-carbohydrate and high-fat challenges on postprandial endothelial function as well as the potential role of oxidative stress in such postprandial metabolic alterations. Moreover, the present review will differentiate the postprandial endothelial and oxidative impact of meals rich in varying fatty acid types.
Seasonal changes of foraging habitats and prey species in the Japanese Crested Ibis Nipponia nippon reintroduced on Sado Island, Japan
Authors: ENDO CHIHIRO , NAGATA HISASHI
Published: November 2012

Seasonal foraging habitats, prey species and foraging frequency of Japanese Crested Ibis Nipponia nippon in farmland were studied one year after its reintroduction on Sado Island, Japan. Paddies were the main foraging habitat in spring, early summer, autumn and winter. In late summer, ibises often used levees around paddies, grasslands, uncropped paddies and abandoned paddies. Small invertebrates were important prey components in terms of frequency (70–90%) throughout the year. Ibises took Misgurnus loaches (less than 20% of prey captured) throughout the year; the capture rate of loaches in ditches was especially high in winter. Ibises depended on terrestrial invertebrates, including earthworms, particularly in late summer. No clear correlations between the rate of capture for each prey species and the proportion of habitat use in each season were detected. However, abandoned and uncropped paddies provided suitable habitats for the ibis because human disturbance was relatively low and the rate of capture for each prey type was relatively high throughout the year. Management of grass height in grasslands and on levees around the paddies will be effective in ensuring the availability of foraging habitats in late summer. Seasonal changes in the availability of foraging habitats in farmland ecosystems should be considered when designing effective management strategies for the establishment of Japanese Crested Ibis populations.
Correlative ultrastructural analysis of extracellular DNA in early Enterococcus faecalis biofilms
Authors: Barnes A. , Ballering K.S. , Leibman R.S. , Wells C.L. , Dunny G.M.
Published: November 2012

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.
Morphological Effects of Quaternary Ammonium Compounds on Staphylococcal Biofilms
Authors: Zerdoum A. , Libera M. , Crismaru M. , Loontjens J.A. , van der Mei H. , Busscher H.
Published: November 2012

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.
Anti-aggregation Potential of Sugars against Strepococcus mutans in co-culture with Lactobacillus rhamnosus
Authors: Park Y. , Queenan C. , Calabro A. , Leonardi D.
Published: November 2012

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.
An Assessment of Measurements Generated by Scanning Electron Microscopy for Determining Microbial Contributions to Biocorrosion
Authors: Johnson C.N. , Drilling H.S. , Lawson P.A. , Stevenson B.S.
Published: November 2012

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.
Mineralogical Analyses in Forensic Practise
Authors: Kotrly M. , Turková I. , Grunwaldova V.
Published: November 2012

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.
Dichroic Spectral Measurements For Classification And Discrimination Of Dyed Fiber And Film Evidence
Authors: Reffner J.A. , Purcell D.K.
Published: November 2012

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.
Bacterial Endospore Sterilization and Ultrastructure Study
Authors: Brantner C.A. , Pope R.K. , Hannah R.M. , Burans J.P.
Published: November 2012

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.
Visualizing BAR-Dependent Membrane Remodeling
Authors: Mim C. , Gawronski-Salerno J. , Unger V.M. , Frost A.
Published: November 2012

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.
Structure and Heterogeneity of the COPII Coat
Authors: O'Donnell J. , Zhang Q. , Noble A. , Bhattacharya N. , Hariri H. , Stagg S.
Published: November 2012

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.
HIV-1 Biogenesis Studied by Cellular Cryo-Electron Tomography and Biochemical in vitro Reconstitution
Authors: Carlson L. , Hurley J.H. , Grünewald K. , Kräusslich H. , Briggs J.
Published: November 2012

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.
Structural Analysis of Dynamin Reveals a Mechanism of Membrane Fission
Authors: Hinshaw J.
Published: November 2012

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.
Spatial Structure of Cytoplasmic Actin Filaments with Special Reference to the Association with Nuclear Envelope.
Authors: Uskura J. , Minakata S.
Published: November 2012

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.
Effect of vitamin D deficiency during pregnancy on offspring bone structure, composition and quality in later life
Authors: Lanham S. A. , Roberts C. , Habgood A. K. , Alexander S. , Burne T. H. J. , Eyles D. W. , Trueman C. N. , Cooper M. , McGrath J. J. , Oreffo R. O. C.
Published: November 2012

During foetal development, calcium requirements are met as a consequence of maternal adaptations independent of vitamin D status. In contrast, after birth, dependency on vitamin D appears necessary for calcium metabolism and skeletal health. We used a rodent model (Sprague-Dawley rats), to determine if maternal vitamin D deficiency during pregnancy had a deleterious effect on bone structure at birth. Vitamin D deplete females were maintained under deplete conditions until birth of the pups, whereupon all dams were fed a vitamin D replete diet. Offspring were harvested at birth, and 140 days of age. Bones were analyzed using micro-computed tomography and strength tested to study differences in bone structure, density and strength and subjected to elemental analysis using plasma mass spectrometry to determine strontium, barium and calcium contents. Offspring from deplete mothers displayed altered trabecular parameters in the femur at birth and 140 days of age. In addition, at 140 days of age there was evidence of premature mineralization of the secondary ossification centre of the femoral head. Elemental analysis showed increased strontium uptake in the femur of the developmentally vitamin D-deficient offspring. Vitamin D depletion during development in the offspring may have a long-lasting effect, despite repletion of vitamin D from birth. This may have consequences for human health given the low vitamin D levels seen during pregnancy and current lifestyle of sun avoidance due to the risk of skin cancer.
Psychopathology and adversities from early- to late-adolescence: a general population follow-up study with the CBCL DSM-Oriented Scales
Authors: Nobile M. , Colombo P. , Bellina M. , Molteni M. , Simone D. , Nardocci F. , Carlet O. , Battaglia M.
Published: November 2012

Aims.

Adolescence is a critical transition phase between childhood and adulthood, when the burden of mental disorder may still be prevented. The aim of this study was to evaluate the continuity and discontinuity of behavioural problems in adolescence while taking into account the multiple co-variation of psychopathological traits and the complex role of recent stressful life events (SLEs).

Methods.

This is a 5-year follow-up investigation of emotional and behavioural problems assessed by the newly developed Child Behavior Checklist (CBCL) DSM-Oriented Scales (DOSs) in 420 general population subjects aged 15–19 years.

Results.

The DOSs showed good stability, even when multiple co-variation was taken into account. Longitudinal data showed that homotypic evolution of psychopathology was to be expected in the first place. Equifinality and multifinality were also found. Oppositional Defiant Problems emerged to be polyvalent predictors of both internalizing and externalizing problems. Furthermore, Oppositional Defiant Problems predicted more SLEs, which in turn predicted more Depression, Anxiety and Oppositional Defiant Problems. Mediational analyses confirmed the role of SLEs in partially accounting for the continuity of Oppositional Defiant Problems and for the heterotypic progression towards Affective Problems.

Conclusions.

These data underscore early adolescence behavioural problems as an important focus for primary and secondary intervention.
Ca2+ enhances Aβ polymerization rate and fibrillar stability in a dynamic manner
Authors: Brännström Kristoffer , Öhman Anders , Lindhagen-Persson Malin , Olofsson Anders
Published: November 2012

Identifying factors that affect the self-assembly of Aβ (amyloid-β peptide) is of utmost importance in the quest to understand the molecular mechanisms causing AD (Alzheimer's disease). Ca2+ has previously been shown to accelerate both Aβ fibril nucleation and maturation, and dysregulated Ca2+ homoeostasis frequently correlates with development of AD. The mechanisms regarding Ca2+ binding, as well as its effect on fibril kinetics, are not fully understood. Using a polymerization assay we show that Ca2+ in a dynamic and reversible manner enhances both the elongation rate and fibrillar stability, where specifically the ‘dock and lock’ phase mechanism is enhanced. Through NMR analysis we found that Ca2+ affects the fibrillar architecture. In addition, and unexpectedly, we found that Ca2+ does not bind the free Aβ monomer. This implies that Ca2+ binding requires an architecture adopted by assembled peptides, and consequently is mediated through intermolecular interactions between adjacent peptides. This gives a mechanistic explanation to the enhancing effect on fibril maturation and indicates structural similarities between prefibrillar structures and mature amyloid. Taken together we show how Ca2+ levels affect the delicate equilibrium between the monomeric and assembled Aβ and how fluctuations in vivo may contribute to development and progression of the disease.
A long way to the electrode: how do Geobacter cells transport their electrons?
Authors: Bonanni Pablo Sebastián , Schrott Germán David , Busalmen Juan Pablo
Published: November 2012

The mechanism of electron transport in Geobacter sulfurreducens biofilms is a topic under intense study and debate. Although some proteins were found to be essential for current production, the specific role that each one plays in electron transport to the electrode remains to be elucidated and a consensus on the mechanism of electron transport has not been reached. In the present paper, to understand the state of the art in the topic, electron transport from inside of the cell to the electrode in Geobacter sulfurreducens biofilms is analysed, reviewing genetic studies, biofilm conductivity assays and electrochemical and spectro-electrochemical experiments. Furthermore, crucial data still required to achieve a deeper understanding are highlighted.
Rho family GTPases
Authors: Hall Alan
Published: November 2012

Rho GTPases comprise a family of molecular switches that control signal transduction pathways in eukaryotic cells. A conformational change induced upon binding GTP promotes an interaction with target (effector) proteins to generate a cellular response. A highly conserved function of Rho GTPases from yeast to humans is to control the actin cytoskeleton, although, in addition, they promote a wide range of other cellular activities. Changes in the actin cytoskeleton drive many dynamic aspects of cell behaviour, including morphogenesis, migration, phagocytosis and cytokinesis, and the dysregulation of Rho GTPases is associated with numerous human diseases and disorders.
Magnetochrome: a c-type cytochrome domain specific to magnetotatic bacteria
Authors: Siponen Marina I. , Adryanczyk Géraldine , Ginet Nicolas , Arnoux Pascal , Pignol David
Published: November 2012

Magnetotactic bacteria consist of a group of taxonomically, physiologically and morphologically diverse prokaryotes, with the singular ability to align with geomagnetic field lines, a phenomenon referred to as magnetotaxis. This magnetotactic property is due to the presence of iron-rich crystals embedded in lipidic vesicles forming an organelle called the magnetosome. Magnetosomes are composed of single-magnetic-domain nanocrystals of magnetite (Fe3O4) or greigite (Fe3S4) embedded in biological membranes, thereby forming a prokaryotic organelle. Four specific steps are described in this organelle formation: (i) membrane specialization, (ii) iron acquisition, (iii) magnetite (or greigite) biocrystallization, and (iv) magnetosome alignment. The formation of these magnetic crystals is a genetically controlled process, which is governed by enzyme-catalysed processes. On the basis of protein sequence analysis of genes known to be involved in magnetosome formation in Magnetospirillum magneticum AMB-1, we have identified a subset of three membrane-associated or periplasmic proteins containing a double cytochrome c signature motif CXXCH: MamE, MamP and MamT. The presence of these proteins suggests the existence of an electron-transport chain inside the magnetosome, contributing to the process of biocrystallization. We have performed heterologous expression in E. coli of the cytochrome c motif-containing domains of MamE, MamP and MamT. Initial biophysical characterization has confirmed that MamE, MamP and MamT are indeed c-type cytochromes. Furthermore, determination of redox potentials for this new family of c-type cytochromes reveals midpoint potentials of −76 and −32 mV for MamP and MamE respectively.
Microscale gradients and their role in electron-transfer mechanisms in biofilms
Authors: Beyenal Haluk , Babauta Jerome T.
Published: November 2012

The chemical and electrochemical gradients in biofilms play a critical role in electron-transfer processes between cells and a solid electron acceptor. Most of the time, electron-transfer processes have been investigated in the bulk phase, for a biofilm electrode or for an isolated component of a biofilm. Currently, the knowledge of chemical and electrochemical gradients in living biofilms respiring on a solid surface is limited. We believe the chemical and electrochemical gradients are critical for explaining electron-transfer mechanisms. The bulk conditions, an isolated part of a biofilm or a single cell cannot be used to explain electron-transfer mechanisms in biofilm systems. In addition, microscale gradients explain how the reactor configuration plays a critical role in electron-transfer processes.
The quest to achieve the detailed structural and functional characterization of CymA
Authors: Louro Ricardo O. , Paquete Catarina M.
Published: November 2012

Shewanella oneidensis MR-1 is a sediment organism capable of dissimilatory reduction of insoluble metal compounds such as those of Fe(II) and Mn(IV). This bacterium has been used as a model organism for potential applications in bioremediation of contaminated environments and in the production of energy in microbial fuel cells. The capacity of Shewanella to perform extracellular reduction of metals is linked to the action of several multihaem cytochromes that may be periplasmic or can be associated with the inner or outer membrane. One of these cytochromes is CymA, a membrane-bound tetrahaem cytochrome localized in the periplasm that mediates the electron transfer between the quinone pool in the cytoplasmic membrane and several periplasmic proteins. Although CymA has the capacity to regulate multiple anaerobic respiratory pathways, little is known about the structure and functional mechanisms of this focal protein. Understanding the structure and function of membrane proteins is hampered by inherent difficulties associated with their purification since the choice of the detergents play a critical role in the protein structure and stability. In the present mini-review, we detail the current state of the art in the characterization of CymA, and add recent information on haem structural behaviour for CymA solubilized in different detergents. These structural differences are deduced from NMR spectroscopy data that provide information on the geometry of the haem axial ligands. At least two different conformational forms of CymA are observed for different detergents, which seem to be related to the micelle size. These results provide guidance for the discovery of the most promising detergent that mimics the native lipid bilayer and is compatible with biochemical and structural studies.
Molecular structure and free energy landscape for electron transport in the decahaem cytochrome MtrF
Authors: Breuer Marian , Zarzycki Piotr , Shi Liang , Clarke Thomas A. , Edwards Marcus J. , Butt Julea N. , Richardson David J. , Fredrickson James K. , Zachara John M. , Blumberger Jochen , Rosso Kevin M.
Published: November 2012

The free energy profile for electron flow through the bacterial decahaem cytochrome MtrF has been computed using thermodynamic integration and classical molecular dynamics. The extensive calculations on two versions of the structure help to validate the method and results, because differences in the profiles can be related to differences in the charged amino acids local to specific haem groups. First estimates of reorganization free energies λ yield a range consistent with expectations for partially solvent-exposed cofactors, and reveal an activation energy range surmountable for electron flow. Future work will aim at increasing the accuracy of λ with polarizable forcefield dynamics and quantum chemical energy gap calculations, as well as quantum chemical computation of electronic coupling matrix elements.
Mineral respiration under extreme acidic conditions: from a supramolecular organization to a molecular adaptation in Acidithiobacillus ferrooxidans
Authors: Roger Magali , Castelle Cindy , Guiral Marianne , Infossi Pascale , Lojou Elisabeth , Giudici-Orticoni Marie-Thérèse , Ilbert Marianne
Published: November 2012

Acidithiobacillus ferrooxidans is an acidophilic chemolithoautotrophic Gram-negative bacterium that can derive energy from the oxidation of ferrous iron at pH 2 using oxygen as electron acceptor. The study of this bacterium has economic and fundamental biological interest because of its use in the industrial extraction of copper and uranium from ores. For this reason, its respiratory chain has been analysed in detail in recent years. Studies have shown the presence of a functional supercomplex that spans the outer and the inner membranes and allows a direct electron transfer from the extracellular Fe2+ ions to the inner membrane cytochrome c oxidase. Iron induces the expression of two operons encoding proteins implicated in this complex as well as in the regeneration of the reducing power. Most of these are metalloproteins that have been characterized biochemically, structurally and biophysically. For some of them, the molecular basis of their adaptation to the periplasmic acidic environment has been described. Modifications in the metal surroundings have been highlighted for cytochrome c and rusticyanin, whereas, for the cytochrome c oxidase, an additional partner that maintains its stability and activity has been demonstrated recently.