bluuebunny/crossref_metadata_2025_split huggingface dataset:
A derivative‐based interpretation approach to estimating source parameters of simple 2D magnetic sources from Euler deconvolution, the analytic‐signal method and analytical expressions of the anomalies
Authors: Doo Wen‐Bin , Hsu Shu‐Kun , Yeh Yi‐Ching 
Published: February 2007

ABSTRACTThe major advantage of using either the analytic‐signal or the Euler‐deconvolution technique is that we can determine magnetic‐source locations and depths independently of the ambient earth magnetic parameters. In this study, we propose adopting a joint analysis of the analytic signal and Euler deconvolution to estimate the parameters of 2D magnetic sources. The results can avoid solution bias from an inappropriate magnetic datum level and can determine the horizontal locations, depths, structural types (indices), magnetization contrasts and/or structural dips. We have demonstrated the feasibility of the proposed method on 2D synthetic models, such as magnetic contacts (faults), thin dikes and cylinders. However, the method fails to solve the parameters of magnetic sources if there is severe interference between the anomalies of two adjacent magnetic sources.
Constraints on velocity‐depth trends from rock physics models
Authors: Japsen Peter , Mukerji Tapan , Mavko Gary 
Published: February 2007

ABSTRACTEstimates of depth, overpressure and amount of exhumation based on sonic data for a sedimentary formation rely on identification of a normal velocity–depth trend for the formation. Such trends describe how sonic velocity increases with depth in relatively homogeneous, brine‐saturated sedimentary formations as porosity is reduced during normal compaction (mechanical and chemical). Compaction is ‘normal’ when the fluid pressure is hydrostatic and the thickness of the overburden has not been reduced by exhumation. We suggest that normal porosity at the surface for a given lithology should be constrained by its critical porosity, i.e. the porosity limit above which a particular sediment exists only as a suspension. Consequently, normal velocity at the surface of unconsolidated sediments saturated with brine approaches the velocity of the sediment in suspension. Furthermore, porosity must approach zero at infinite depth, so the velocity approaches the matrix velocity of the rock and the velocity–depth gradient approaches zero. For sediments with initially good grain contact (when porosity is just below the critical porosity), the velocity gradient decreases with depth. By contrast, initially compliant sediments may have a maximum velocity gradient at some depth if we assume that porosity decreases exponentially with depth. We have used published velocity–porosity–depth relationships to formulate normal velocity–depth trends for consolidated sandstone with varying clay content and for marine shale dominated by smectite/illite. The first relationship is based on a modified Voigt trend (porosity scaled by critical porosity) and the second is based on a modified time‐average equation. Baselines for sandstone and shale in the North Sea agree with the established constraints and the shale trend can be applied to predict overpressure. A normal velocity–depth trend for a formation cannot be expressed from an arbitrary choice of mathematical functions and regression parameters, but should be considered as a physical model linked to the velocity–porosity transforms developed in rock physics.
Vegetation loss alters soil nitrogen dynamics in an Arctic salt marsh
Authors: BUCKERIDGE KATE M. , JEFFERIES ROBERT L. 
Published: February 2007

Summary

Plant and microbial nitrogen (N) dynamics were examined in soils of an Arctic salt marsh beneath goose‐grazed swards and in degraded soils. The degraded soils are the outcome of intensive destructive foraging by geese, which results in vegetation loss and near‐irreversible changes in soil properties. The objective of the study was to determine whether vegetation loss led to a decline in microbial activity and a redistribution of N amongst the different soil N pools that potentially could adversely affect plant regrowth.
In situ N allocation between plants, microbes and soil was determined based on injection of 15NH4Cl into soil cores; changes in isotopic ratios and N concentrations in the different pools were measured after 24 h. Degraded soils, in contrast to vegetated soils, were characterized by a decline in microbial biomass, reduced microbial 15N excess, reduced rates of gross N immobilization and an increased microbial residency time of 15N. In vegetated soils, both microbes and the forage grass, Puccinellia phryganodes, accumulated 15N such that little remained in the soil abiotic phase after 24 h, unlike in degraded soils.
The decline in microbial activity in degraded soils may be linked to a low availability of soil carbon in the absence of plants and to deteriorating abiotic conditions, including the occurrence of hypersalinity in summer.
Not all biotic processes respond similarly to the change in ecosystem state. Unlike vascular plant productivity and goose foraging which are absent in degraded soils, soil microbial activity is maintained, albeit at a lower level. In spite of this activity, the greater proportion of 15N in degraded soils is in the abiotic pool rather than in microbial biomass with an increased potential for soil N loss from leaching and soil erosion.
Disturbance linked to herbivory often triggers catastrophic shifts in ecosystem properties resulting in vegetation loss and changes in soil biogeochemical cycling that are irreversible, at least on a decadal time scale, and lead to the loss of N and other nutrients required for plant growth. These results clearly illustrate that microbial activity does not compensate for the effects of plant removal on soil N retention.
Above‐ and below‐ground competition cues elicit independent responses
Authors: MURPHY GUILLERMO P. , DUDLEY SUSAN A. 
Published: February 2007

Summary

Plants sharing pots have been observed to show more allocation to roots than do solitary plants, even when resources per plant are constant, indicating plasticity to root neighbours. Lowered red to far‐red ratio (R : FR), a cue of above‐ground competition, is known to cause increased stem elongation and decreased allocation to roots. In nature, however, cues for above‐ and below‐ground competition are likely to be experienced simultaneously, and may elicit contradictory responses.
We investigated whether the presence of the above‐ground competition cue (low R : FR) affected the responses to the below‐ground competition cue (presence of neighbouring roots) in soybean and whether these responses depended on the presence or absence of symbiotic bacteria or on the availability of nutrients.
In a fully factorial study in a growth room, light quality, root neighbours, nutrient availability and Bradyrhizobium inoculation were manipulated. Stem elongation and biomass allocation were measured.
As predicted, plants allocated more to roots in the presence of root neighbours, regardless of R : FR, Bradyrhizobium and nutrient treatment. Plants elongated under low R : FR, although the degree of elongation was affected by Bradyrhizobium and nutrients. R : FR did not affect allocation to roots. Surprisingly, we found no reduction in reproductive allocation and therefore no ‘tragedy of the commons’ cost; instead, growth was increased in the presence of root neighbours.
We conclude that soybean responds to both competition cues independently, but that below‐ground resources such as Bradyrhizobium and nutrient availability moderate the morphological responses to above‐ and below‐ground competition.
To our knowledge, this is the first study that tests responses to above‐ and below‐ground competition cues simultaneously and that shows the independence of these responses. This study provides supporting evidence that plants can sense neighbouring roots as a cue of impending competition and demonstrates clearly that the root allocation response is not dependent on the presence of Bradyrhizobium or an artefact of inadvertent R : FR manipulation.
Functional impairment in patients with mania: baseline results of the EMBLEM study
Authors: Goetz I , Tohen M , Reed C , Lorenzo M , Vieta E ,   the EMBLEM Advisory Board
Published: February 2007

Objectives:  The European Mania in Bipolar Longitudinal Evaluation of Medication (EMBLEM) is a large‐scale prospective observational multicentre study to evaluate the longitudinal course of bipolar disorder and its associations with pharmacological treatment following an acute manic or mixed episode. We present an overview of the study design and patient characteristics at baseline while focusing on factors influencing work performance in the year prior to enrolment.Methods:  A total of 530 investigators across 14 European countries enrolled 3,681 patients with acute mania between December 2002 and June 2004. Longitudinal observations are ongoing until July 2006. Socio‐demographic variables, psychiatric history, clinical status and information on pharmacological treatment for bipolar disorder were recorded. Items from the SLICE of LIFE were applied, including a measure of work impairment during the previous year. The distribution of the baseline characteristics was analysed with descriptive statistics. Eighteen variables were investigated as hypothesized risk factors for work impairment applying logistic regression models.Results:  In the previous year, 28 and 68% of patients were classified as having ‘low’ and ‘high’ work impairment, respectively. Clinical Global Impression – Bipolar Disorder (CGI‐BP) overall, CGI‐BP depression at baseline, rapid cycling during the previous 12 months, age between 35 and 64 years, substance abuse other than alcohol and cannabis and living without a partner or as dependent household member were significantly associated with work impairment during the previous year.Conclusions:  EMBLEM is to our knowledge the largest prospective observational study assessing patients during and after an acute episode of mania. Work impairment is significant in the year prior to an acute episode of mania.
Long‐term social functioning after depression treated by psychiatrists: a review
Authors: Kennedy Noel , Foy Kevin , Sherazi Rafay , McDonough Michael , McKeon Patrick 
Published: February 2007

Objectives: Numerous long‐term studies of depression in psychiatric settings have shown a poor clinical outcome but little emphasis has been placed on psychosocial or functional outcome in studies to date. This article reviews published data on long‐term social functioning after depression and considers why psychosocial recovery appears delayed compared with clinical recovery.Methods: Searches were carried out of the databases MEDLINE, PSYCHLIT and EMBASE for articles published from 1980 using keywords relating to social and functional outcomes of unipolar and bipolar depression. Review articles and relevant textbooks were also searched.Results: The few outcome studies published have described long‐term functional impairment in the majority of patients but have been limited by methodological shortcomings. Psychosocial impairment tends to persist even after clinical remission from depression. Residual symptomatology after remission from depression may lead to enduring psychosocial impairment, as may subtle neurocognitive deficits. Axis I and II comorbidities predict a poor psychosocial outcome, but episodes of depression do not appear to lead to personality ‘scarring’.Conclusions: Future outcome studies need to focus on longitudinal social functioning. Full functional recovery after an episode of depression should be the goal of treatment as enduring residual symptoms lead to long‐term psychosocial impairment.
Functional outcome in bipolar disorder: the role of clinical and cognitive factors
Authors: Martinez‐Aran A , Vieta E , Torrent C , Sanchez‐Moreno J , Goikolea JM , Salamero M , Malhi GS , Gonzalez‐Pinto A , Daban C , Alvarez‐Grandi S , Fountoulakis K , Kaprinis G , Tabares‐Seisdedos R , Ayuso‐Mateos JL 
Published: February 2007

Introduction: Few studies have examined the clinical, neuropsychological and pharmacological factors involved in the functional outcome of bipolar disorder despite the gap between clinical and functional recovery.Methods: A sample of 77 euthymic bipolar patients were included in the study. Using ana prioridefinition of low versus good functional outcome, based on the psychosocial items of the Global Assessment of Functioning (GAF, DSM‐IV), and taking also into account their occupational adaptation, the patients were divided into two groups: good or low occupational functioning. Patients with high (n = 46) and low (n = 31) functioning were compared on several clinical, neuropsychological and pharmacological variables and the two patient groups were contrasted with healthy controls (n = 35) on cognitive performance.Results: High‐ and low‐functioning groups did not differ with respect to clinical variables. However, bipolar patients in general showed poorer cognitive performance than healthy controls. This was most evident in low‐functioning patients and in particular on verbal memory and executive function measures.Conclusions: Low‐functioning patients were cognitively more impaired than highly functioning patients on verbal recall and executive functions. The variable that best predicted psychosocial functioning in bipolar patients was verbal memory.
Acanthamoeba polyphaga resuscitates viable non‐culturable Legionella pneumophila after disinfection
Authors: García María Teresa , Jones Snake , Pelaz Carmen , Millar Richard D. , Abu Kwaik Yousef 
Published: February 2007

SummaryAmoebae are the natural hosts for Legionella pneumophila and play essential roles in bacterial ecology and infectivity to humans. When L. pneumophila colonizes an aquatic installation, it can persist for years despite repeated treatments with disinfectants. We hypothesized that freshwater amoebae play an important role in bacterial resistance to disinfectants, and in subsequent resuscitation of viable non‐culturable (VNC) L. pneumophila that results in re‐emergence of the disease‐causing strain in the disinfected water source. Our work showed that in the absence of Acanthamoeba polyphaga, seven L. pneumophila strains became non‐culturable after treatment by 256 p.p.m. of sodium hypochlorite (NaOCl). In contrast, intracellular L. pneumophila within A. polyphaga was resistant to 1024 p.p.m. of NaOCl. In addition, L. pneumophila‐infected A. polyphaga exhibited increased resistance to NaOCl. When chlorine‐sterilized water samples were co‐cultured with A. polyphaga, the non‐culturable L. pneumophila were resuscitated and proliferated robustly within A. polyphaga. Upon treatment by NaOCl, uninfected amoebae differentiated into cysts within 48 h. In contrast, L. pneumophila‐infected A. polyphaga failed to differentiate into cysts, and L. pneumophila was never detected in cysts of A. polyphaga. We conclude that amoebic trophozoites protect intracellular L. pneumophila from eradication by NaOCl, and play an essential role in resuscitation of VNC L. pneumophila in NaOCl‐disinfected water sources. Intracellular L. pneumophila within trophozoites of A. polyphaga block encystation of the amoebae, and the resistance of both organisms to NaOCl is enhanced. To ensure long‐term eradication and complete loss of the VNC state of L. pneumophila, we recommend that Legionella‐protozoa co‐culture should be an important tool to ensure complete loss of the VNC state of L. pneumophila.
Improving asthma discharge management in relation to emergency departments: The ADMIRE project
Authors: Kelly Anne‐Maree , Clooney Megan 
Published: February 2007

AbstractThe present paper describes the process, outcomes and lessons learned from a federally funded, multicentre action research project aimed at improving discharge practices for asthma patients who attend ED and are discharged home. Thirty‐two ED participated and worked locally to improve discharge practices using previously published best‐practice guidelines. Although they achieved some improvements, major barriers to best‐practice discharge outside ED control were identified, including access to GP, hospital policies regarding supply of medications and access to appropriate asthma education. The ED developed some useful tools to assist with improving asthma management that have been compiled as a toolkit and are available online.
Osmotic myelinolysis syndrome after treatment of severe deamino arginine vasopressin‐associated hyponatraemia: Pitfalls in emergency medicine
Authors: Gutenstein Marc 
Published: February 2007

AbstractHyponatraemia is among the more common electrolyte abnormalities encountered in the ED. Both the primary disturbance and its correction can result in life‐threatening neurological sequelae. Osmotic myelinolysis syndrome is one such complication and is associated with the rapid correction of hyponatraemia. The present case report describes the mechanism of severe hyponatraemia in a patient taking deamino arginine vasopressin, and the subsequent development of both central pontine and extrapontine myelinolysis after rapid correction of sodium levels. Implications for the emergency management of such patients are discussed.
Regulation of Sulfur Assimilation Pathways in
Burkholderia cenocepacia
: Identification of Transcription Factors CysB and SsuR and Their Role in Control of Target Genes
Authors: Iwanicka-Nowicka Roksana , Zielak Agata , Cook Anne M. , Thomas Mark S. , Hryniewicz Monika M. 
Published: February 2007

ABSTRACT

Two genes encoding transcriptional regulators involved in sulfur assimilation pathways in
Burkholderia cenocepacia
strain 715j have been identified and characterized functionally. Knockout mutations in each of the
B. cenocepacia
genes were constructed and introduced into the genome of 715j by allelic replacement. Studies on the utilization of various sulfur sources by 715j and the obtained mutants demonstrated that one of the
B. cenocepacia
regulators, designated CysB, is preferentially involved in the control of sulfate transport and reduction, while the other, designated SsuR, is required for aliphatic sulfonate utilization. Using transcriptional promoter-
lacZ
fusions and DNA-binding experiments, we identified several target promoters for positive control by CysB and/or SsuR—
sbpp
(preceding the
sbp cysT cysW cysA ssuR
cluster),
cysIp
(preceding the
cysI cysD1 cysN cysH cysG
cluster),
cysD2p
(preceding a separate cluster,
cysD2 cysNC
), and
ssuDp
(located upstream of the
ssuDCB
operon)—and we demonstrated overlapping functions of CysB and SsuR at particular promoters. We also demonstrated that the
cysB
gene is negatively controlled by both CysB and SsuR but the
ssuR
gene itself is not significantly regulated as a separate transcription unit. The function of
B. cenocepacia
CysB (in vivo and in vitro) appeared to be independent of the presence of acetylserine, the indispensable coinducer of the CysB regulators of
Escherichia coli
and
Salmonella
. The phylogenetic relationships among members of the “CysB family” in the γ and β subphyla are presented.
Preventing suicide by jumping: the effect of a bridge safety fence
Authors: Pelletier Andrew R 
Published: February 2007

Objective:To evaluate the effect of a bridge safety fence in preventing suicide.Methods:We examined suicides from jumping off the Memorial Bridge in Augusta, Maine, from 1 April 1960 to 31 July 2005. The safety fence was installed during 1983, the mid-point of the study period.Results:14 suicides from the bridge were identified; all occurred before installation of the safety fence. The number of suicides by jumping from other structures remained unchanged after installation of the fence.Conclusion:The safety fence was effective in preventing suicides from the bridge. There was no evidence that suicidal individuals sought alternative sites for jumping.
Dietary Folate Intake in Combination with MTHFR C677T Genotype and Promoter Methylation of Tumor Suppressor and DNA Repair Genes in Sporadic Colorectal Adenomas
Authors: van den Donk Maureen , van Engeland Manon , Pellis Linette , Witteman Ben J.M. , Kok Frans J. , Keijer Jaap , Kampman Ellen 
Published: February 2007

AbstractMethylation of the promoter region of tumor suppressor genes is increasingly recognized to play a role in cancer development through silencing of gene transcription. We examined the associations between dietary folate intake, MTHFR C677T genotype, and promoter methylation of six tumor suppressor and DNA repair genes. Patients with colorectal adenoma (n = 149) and controls (n = 286) with folate intake in the upper or lower tertile with the CC or TT genotype were selected from a case-control study. Methylation-specific PCRs were conducted on colorectal adenoma specimens. The percentages of promoter methylation ranged from 15.7% to 64.2%. In case-case comparisons, folate was inversely associated with promoter methylation, especially among TT homozygotes. Case-control comparisons suggested that folate was not associated with the occurrence of adenomas with promoter methylation, and increased the risk of unmethylated adenomas, especially in TT homozygotes. The interactions between folate and MTHFR genotype were most pronounced for O6-MGMT: compared with CC homozygotes with low folate intake, the adjusted odds ratios (95% confidence interval) of having a methylated O6-MGMT promoter were 3.39 (0.82-13.93) for TT homozygotes with low folate intake and 0.37 (0.11-1.29) for TT homozygotes with high folate intake (P interaction = 0.02); the odds ratios for the occurrence of adenomas without methylation were 0.57 (0.16-2.11) for TT homozygotes with low folate intake and 3.37 (1.17-9.68) for TT homozygotes with high folate intake (P interaction = 0.03). In conclusion, folate intake seems to be inversely associated with promoter methylation in colorectal adenomas in case-case comparisons, and was positively associated with the occurrence of adenomas without promoter methylation in case-control comparisons, especially for TT homozygotes. (Cancer Epidemiol Biomarkers Prev 2007;16(2):327–33)
Exploring an ensemble approach to estimating skill in multiproxy palaeoclimate reconstructions
Authors: van der Schrier G. , Osborn T. J. , Briffa K. R. , Cook E. R. 
Published: February 2007

This paper describes an approach that gives an estimate of the reconstructive skill of a proxy-based palaeoclimatological reconstruction. Uncertainties in proxy data are likely to be reflected in variations in reconstructive skill of the proxy-based climatic reconstructions. The method is based on making an ensemble of reconstructions, providing a probability distribution of each reconstruction estimate. The relative breadth of the distribution for a particular reconstructed value should give an indication of the reconstructive skill. The ensemble reconstruction approach draws on the ensemble prediction system as used for operational weather forecasting. The ensemble reconstruction approach is tested using a recent multiproxy reconstruction of the winter North Atlantic Oscillation (NAO) index. It is shown that the ensemble approach provides a representation of the degree of certainty associated with the reconstructed NAO-index values.
Fabrication of Superhydrophobic Surface on Magnesium Alloy
Authors: Liang Jun , Guo Zhiguang , Fang Jian , Hao Jingcheng 
Published: February 2007

Abstract
A stable biomimetic superhydrophobic surface on magnesium alloy was fabricated by microarc oxidation pretreatment and followed by chemical modification based on lotus effect. The as-prepared surface showed an interesting micro- and nanoscale binary structure, exhibiting a good superhydrophobic property with a water contact angle larger than 150° and a water sliding angle less than 8°.