bluuebunny/crossref_metadata_2025_split huggingface dataset:
Carbon Monoxide Alleviates Salt‐Induced Oxidative Damage in Wheat Seedling Leaves
Authors: Huang Ben‐Kai , Xu Sheng , Xuan Wei , Li Ming , Cao Ze‐Yu , Liu Kai‐Li , Ling Teng‐Fang , Shen Wen‐Biao 
Published: March 2006

AbstractCarbon monoxide (CO), a by‐product released during the degradation of heme by heme oxygenases (EC 1.14.99.3) in animals, is regarded as an important physiological messenger or bioactive molecule involved in many biological events that has been recently reported as playing a major role in mediating the cytoprotection against oxidant‐induced lung injury. In the present study, we first determined the protective effect of exogenous CO against salt‐induced oxidative damage in wheat seedling leaves. Wheat seedlings treated with 0.01 μmol/L hematin as the CO donor demonstrated significant reversal of chlorophyll decay, dry weight, and water loss induced by 300 mmol/L NaCl stress. Interestingly, the increase in lipid peroxidation observed in salt‐treated leaves was reversed by 0.01 nmol/L hematin treatment. Time‐course analyses showed that application of 0.01 μmol/L hematin enhanced guaiacol peroxidase, superoxide dismutase, ascorbate peroxidase and catalase activities in wheat seedling leaves subjected to salt stress. These effects are specific for CO because the CO scavenger hemoglobin (1.2 mg/L) blocked the actions of the CO donor hematin. However, higher concentration of the CO donor (1.0 μmol/L) did not alleviate dry weight and water loss of salt‐stressed wheat seedlings. These results suggest that exogenous application of low levels of a CO donor may be advantageous against salinity toxicity.(Managing editor: Ping He)
Variant Scaling Relationship for Mass‐Density Across Tree‐Dominated Communities
Authors: Li Hai‐Tao , Han Xing‐Guo , Wu Jian‐Guo 
Published: March 2006

AbstractThe past few decades have seen a resurgence of interest in biological allometry. Specifically, a number of recent studies has suggested a ‐4/3 invariant scaling relationship between mass and density that is universally valid for tree‐dominated communities, regardless of their phyletic affiliation or habitat. In the present study, we test this scaling relationship using a comprehensive forest biomass database, including 1 266 plots of six biomes and 17 forest types across China. The present study shows that the scaling exponent of the mass‐density relationship varies across different tree‐dominated communities and habitats. This great variability in the scaling exponent makes any generalization unwarranted. Although inappropriate regression methods can lead to flawed estimation of the scaling exponent, inconsistency of theoretical framework and empirical patterns may have undermined the validity of previous work.(Managing editor: Ya‐Qin Han)
‘I Can't Eat That, It's Purple’: a Geography Field Course in Vanuatu and Fiji
Authors: CONNELL JOHN 
Published: February 2006

AbstractA month‐long field course in the Pacific island states of Vanuatu and Fiji focused on development issues, involving lectures, seminars and much informal interaction. Students completed daily journals as a means of learning, a form of self‐assessment of learning, a way of evaluating their participation in the course and their perception of its value. Journal themes reflected an evolution from unsettling rhetorical questions towards notions of discovery, autonomy, reflexivity and emerging cultural sensitivity. Students developed valuable social skills, and gained first‐hand experience of various concepts of development and social justice. Grading the journals was difficult because of the extent of subjectivity and diverse personal experiences. The course, and the journals, emphasised the diverse values and roles of courses both on, and particularly in, developing countries, despite the substantial costs.
Doing Fieldwork in Development Geography: Research Culture and Research Spaces in Vietnam
Authors: SCOTT STEFFANIE , MILLER FIONA , LLOYD KATE 
Published: February 2006

AbstractRapid socioeconomic and institutional changes in Vietnam since the early 1990s have opened up new geographical spaces for field research. Reflecting on the experiences of three doctoral student researchers engaged in distinct development geography fieldwork projects in Vietnam, this paper profiles some of the conditions and procedures for carrying out fieldwork in order to serve as a basis for comparison of changing ‘fieldwork possibilities’ in Vietnam and other developing and transitional socialist countries.
Exploring the Transition: Coursework to Research‐Based Study in the Geography Honours Year
Authors: SCHWEINSBERG STEPHEN , MCMANUS PHIL 
Published: February 2006

AbstractThe transition from coursework study to independent research is a component of many geography Honours programs in Australian tertiary institutions. Despite being canvassed at the 2003 annual meeting of the Australian Heads of Geography Units, it is a topic that has, to date, received relatively little academic attention.This paper developed from a review of the Geography Honours program at the University of Sydney, conducted by the authors in early 2004. The paper aims to help address the perceived deficiency of research into Honours study. Three topics, related to the Honours year transition, are discussed. These are: the rationale for the Honours year transition from undergraduate coursework to research‐focussed study; the composition and rationale behind coursework programs for geography Honours students, and student‐supervisor relations and their impact on independent Honours research. In the process of examining these issues this paper offers suggestions as to how tertiary geography schools can look to develop their Honours year programs. These recommendations are made with the understanding that all tertiary Honours programs are unique and that issues such as staffing levels and departmental structure will influence what suggestions are appropriate for individual institutions. It is hoped that this paper will encourage more discussion about the nature of the Honours year. It is through such communication that the value of the Honours year in student development can be enhanced
Re‐sampling for Soil‐caesium‐137 to Assess Soil Losses after a 19‐year Interval in a Hunter Valley Vineyard, New South Wales, Australia
Authors: LOUGHRAN ROBERT J. , BALOG RICHARD M. 
Published: February 2006

AbstractSoils in a lower Hunter valley vineyard, New South Wales, Australia, were sampled and analysed for caesium‐137, an indicator of soil erosion status, in 1984–1985 and 2004. From the time of the vineyard's first establishment in 1971 to 1985, estimated soil losses were 250 tonnes (equivalent to 64.2 t ha−1 yr−1). Re‐sampling in 2004 showed that soil losses were 48 tonnes in the 19 years since 1985, equivalent to 9.7 t ha−1 yr−1. The decline in erosion rates may be explained by a change in land and soil management from intensive cultivation to one of no cultivation (sod culture) in 1998, and a lower annual rainfall and fewer rain‐days per year in the period from 1986 to 2004.
Indigenous Research: Whose Priority? Journeys and Possibilities of Cross‐Cultural Research in Geography
Authors: HODGE PAUL , LESTER JOHN 
Published: February 2006

AbstractDecolonising research in geography is part of a broader ‘reflexive’ process which continues to question the positivist status of ‘researcher as observer’. This paper contributes to this reflexive turn, drawing on the particular experiences of a cross‐cultural Honours thesis. The paper is pursued through a parallel journey involving a non‐Indigenous researcher (and author of the cross‐cultural Honours thesis) engaging Indigenous research1 with interpretative insight from an Indigenous adviser or ‘on‐looker’. The methodological difficulties revealed by the parallel journey are emphasised to highlight both the complexities and reflexive possibilities of cross‐cultural research but also to consider potential institutional and pedagogic implications that stem from the experience. One of the substantial findings of the paper is that, by linking Indigenous community priorities to research and coursework, conventional (and often unequal) research relations are minimised and colonising tendencies reduced. By challenging the conventional way that cross‐cultural research is conceived, and the way that institutional practices and research frameworks are implemented, geographers can continue their prolonged and complex efforts at decolonisation of the field and their own practices.
Specificity of aVibrio vulnificusAminopeptidase toward Kinins and Other Peptidyl Substrates
Authors: Richards Gary P. , Nuñez Alberto 
Published: March 2006

ABSTRACTRecently, phosphoglucose isomerase with a lysyl aminopeptidase (PGI-LysAP) activity was identified inVibrio vulnificus. In this paper, we demonstrate the proteolytic cleavage of human-derived peptides by PGI-LysAP ofV. vulnificususing three approaches: (i) a quantitative fluorescent ninhydrin assay for free lysine, (ii) matrix-assisted laser desorption ionization-two-stage time of flight mass spectrometry (MALDI-TOF-TOF), and (iii) Tricine gel electrophoresis. PGI-LysAP hydrolyzed bradykinin, Lys-bradykinin, Lys-(des-Arg9)-bradykinin, neurokinin A, Met-Lys-bradykinin, histatin 8, and a myosin light chain fragment. We detected the proteolytic release of freel-lysine from peptide digests using a rapid, simple, sensitive, and quantitative fluorescent ninhydrin assay, and results were confirmed by MALDI-TOF-TOF. The use of the fluorescent ninhydrin assay to quantitatively detect free lysine hydrolyzed from peptides is the first application of its kind and serves as a paradigm for future studies. The visualization of peptide hydrolysis was accomplished by Tricine gel electrophoresis. Proteolytic processing of kinins alters their affinities toward specific cellular receptors and initiates signal transduction mechanisms responsible for inflammation, vasodilation, and enhanced vascular permeability. By applying novel approaches to determine the proteolytic potential of bacterial enzymes, we demonstrate that PGI-LysAP has broad exopeptidase activity which may enhanceV. vulnificusinvasiveness by altering peptides involved in signal transduction pathways.
Putative Surface Proteins Encoded within a Novel Transferable Locus Confer a High-Biofilm Phenotype to
Enterococcus faecalis
Authors: Tendolkar Preeti M. , Baghdayan Arto S. , Shankar Nathan 
Published: March 2006

ABSTRACT

Enterococci are opportunistic pathogens and among the leading causes of nosocomial infections.
Enterococcus faecalis
, the dominant species among infection-derived isolates, has recently been recognized as capable of forming biofilms on abiotic surfaces in vitro as well as on indwelling medical devices. A few bacterial factors known to contribute to biofilm formation in
E. faecalis
have been characterized. To identify additional factors which may be important to this process, we utilized a Tn
917
-based insertional mutagenesis strategy to generate a mutant bank in a high-biofilm-forming
E. faecalis
strain, E99. The resulting mutant bank was screened for mutants exhibiting a significantly reduced ability to form biofilms. One mutant, P101D12, which showed greater than 70% reduction in its ability to form biofilms compared to the wild-type parent, was further characterized. The single Tn
917
insertion in P101D12 was mapped to a gene,
bee-2
, encoding a probable cell wall-anchored protein. Sequence information for the region flanking
bee-2
revealed that this gene was a member of a locus (termed the
bee
locus for
b
iofilm
e
nhancer in
e
nterococcus) comprised of five genes encoding three putative cell wall-anchored proteins and two probable sortases. Contour-clamped homogeneous electric field gel and Southern hybridization analyses suggested that the
bee
locus is likely harbored on a large conjugative plasmid. Filter mating assays using wild-type E99 or mutant P101D12 as a donor confirmed that the
bee
locus could transfer conjugally at high frequency to recipient
E. faecalis
strains. This represents the first instance of the identification of a mobile genetic element conferring biofilm-forming property in
E. faecalis
.
MotD of
Sinorhizobium meliloti
and Related α-Proteobacteria Is the Flagellar-Hook-Length Regulator and Therefore Reassigned as FliK
Authors: Eggenhofer Elke , Rachel Reinhard , Haslbeck Martin , Scharf Birgit 
Published: March 2006

ABSTRACT

The flagella of the soil bacterium
Sinorhizobium meliloti
differ from the enterobacterial paradigm in the complex filament structure and modulation of the flagellar rotary speed. The mode of motility control in
S. meliloti
has a molecular corollary in two novel periplasmic motility proteins, MotC and MotE, that are present in addition to the ubiquitous MotA/MotB energizing proton channel. A fifth motility gene is located in the
mot
operon downstream of the
motB
and
motC
genes. Its gene product was originally designated MotD, a cytoplasmic motility protein having an unknown function. We report here reassignment of MotD as FliK, the regulator of flagellar hook length. The FliK gene is one of the few flagellar genes not annotated in the contiguous flagellar regulon of
S. meliloti
. Characteristic for its class, the 475-residue FliK protein contains a conserved, compactly folded Flg hook domain in its carboxy-terminal region. Deletion of
fliK
leads to formation of prolonged flagellar hooks (polyhooks) with missing filament structures. Extragenic suppressor mutations all mapped in the cytoplasmic region of the transmembrane export protein FlhB and restored assembly of a flagellar filament, and thus motility, in the presence of polyhooks. The structural properties of FliK are consistent with its function as a substrate specificity switch of the flagellar export apparatus for switching from rod/hook-type substrates to filament-type substrates.
Evidence that the Promoter Can Influence Assembly of Antitermination Complexes at Downstream RNA Sites
Authors: Zhou Ying , Shi Ting , Mozola Mark A. , Olson Eric R. , Henthorn Karla , Brown Susan , Gussin Gary N. , Friedman David I. 
Published: March 2006

ABSTRACT

The N protein of phage λ acts with
Escherichia coli
Nus proteins at RNA sites, NUT, to modify RNA polymerase (RNAP) to a form that overrides transcription terminators. These interactions have been thought to be the primary determinants of the effectiveness of N-mediated antitermination. We present evidence that the associated promoter, in this case the λ early
P
R
promoter, can influence N-mediated modification of RNAP even though modification occurs at a site (NUTR) located downstream of the intervening
cro
gene. As predicted by genetic analysis and confirmed by in vivo transcription studies, a combination of two mutations in
P
R
, at positions −14 and −45 (yielding
P
R-GA
), reduces effectiveness of N modification, while an additional mutation at position −30 (yielding
P
R-GCA
) suppresses this effect. In vivo, the level of
P
R-GA
-directed transcription was twice as great as the wild-type level, while transcription directed by
P
R-GCA
was the same as that directed by the wild-type promoter. However, the rate of open complex formation at
P
R-GA
in vitro was roughly one-third the rate for wild-type
P
R
. We ascribe this apparent discrepancy to an effect of the mutations in
P
R-GCA
on promoter clearance. Based on the in vivo experiments, one plausible explanation for our results is that increased transcription can lead to a failure to form active antitermination complexes with NUT RNA, which, in turn, causes failure to read through downstream termination sites. By blocking antitermination and thus expression of late functions, the effect of increased transcription through
nut
sites could be physiologically important in maintaining proper regulation of gene expression early in phage development.
Photorhabdus
Virulence Cassettes Confer Injectable Insecticidal Activity against the Wax Moth
Authors: Yang G. , Dowling A. J. , Gerike U. , ffrench-Constant R. H. , Waterfield N. R. 
Published: March 2006

ABSTRACT

Two recently sequenced genomes of the insect-pathogenic bacterium
Photorhabdus
and a large
Serratia entomophila
plasmid, pADAP, have phage-related loci containing putative toxin effector genes, designated the “
Photorhabdus
virulence cassettes” (PVCs). In
S. entomophila
, the single plasmid PVC confers antifeeding activity on larvae of a beetle. Here, we show that recombinant
Escherichia coli
expressing PVC-containing cosmids from
Photorhabdus
has injectable insecticidal activity against larvae of the wax moth. Electron microscopy showed that the structure of the PVC products is similar to the structure of the antibacterial R-type pyocins. However, unlike these bacteriocins, the PVC products of
Photorhabdus
have no demonstrable antibacterial activity. Instead, injection of
Photorhabdus
PVC products destroys insect hemocytes, which undergo dramatic actin cytoskeleton condensation. Comparison of the genomic organizations of several PVCs showed that they have a conserved phage-like structure with a variable number of putative anti-insect effectors encoded at one end. Expression of these putative effectors directly inside cultured cells showed that they are capable of rearranging the actin cytoskeleton. Together, these data show that the PVCs are functional homologs of the
S. entomophila
antifeeding genes and encode physical structures that resemble bacteriocins. This raises the interesting hypothesis that the PVC products are bacteriocin-like but that they have been modified to attack eukaryotic host cells.
The evaluation of the risks and benefits of phase II cancer clinical trials by institutional review board (IRB) members: a case study
Authors: van Luijn H E M , Aaronson N K , Keus R B , Musschenga A W 
Published: February 2006

Objectives:There are indications that institutional review board (IRB) members do not find it easy to assess the risks and benefits in medical experiments, although this is their principal duty. This study examined how IRB members assessed the risk/benefit ratio (RBR) of a specific phase II breast cancer clinical trial.Participants and methods:The trial was evaluated by means of a questionnaire administered to 43 members of IRBs at six academic hospitals and specialised cancer centres in the Netherlands. The questionnaire addressed: identification and estimation of inconvenience, toxicity, psychosocial distress, and benefits of trial participation to patients; identification and estimation of benefits to future patients and medical science; assessment of the trial’s RBR; and assessment of its ethical acceptability.Results:Most IRB members expected trial participation to involve fairly or very serious inconvenience, fairly severe to sometimes life-threatening toxicity, and serious psychological and social consequences. Conversely, the perceived likelihood of benefits to patients was modest. Most regarded the study as important, and the balance between risks and benefits to be favourable, and believed that the protocol should be approved. The IRB members’ final judgement on the trial’s ethical acceptability was significantly correlated with their RBR assessment of the protocol.Conclusions:Because most patients who participate in clinical trials hope this will prolong their lives, it is suggested that patient information should better describe the anticipated benefits—for example, the likelihood of prolonging life. This would allow patients to make decisions regarding participation based on realistic expectations.
Concerns over confidentiality may deter adolescents from consulting their doctors. A qualitative exploration
Authors: Carlisle J , Shickle D , Cork M , McDonagh A 
Published: February 2006

Objectives:Young people who are concerned that consultations may not remain confidential are reluctant to consult their doctors, especially about sensitive issues. This study sought to identify issues and concerns of adolescents, and their parents, in relation to confidentiality and teenagers’ personal health information.Setting:Recruitment was conducted in paediatric dermatology and general surgery outpatient clinics, and on general surgery paediatric wards. Interviews were conducted in subjects’ own homes.Methods:Semistructured interviews were used for this exploratory qualitative study. Interviews were carried out with 11 young women and nine young men aged 14–17. Parents of 18 of the young people were interviewed separately. Transcripts of tape recorded interviews provided the basis for a framework analysis.Results:Young women were more concerned than young men, and older teenagers more concerned than younger teenagers, about people other than their general practitioner (GP) having access to their health information. Young people with little experience of the healthcare system were less happy than those with greater knowledge of the National Health Service (NHS) for non-medical staff to access their health information. As they grow older, adolescents become increasingly concerned that their health information should remain confidential.Conclusion:Young people’s willingness to be open in consultations could be enhanced by doctors taking time to explain to them that their discussion is completely confidential. Alternatively, if for any reason confidentiality cannot be assured, doctors should explain why.
Education of ethics committee members: experiences from Croatia
Authors: Borovečki A , ten Have H , Orešković S 
Published: February 2006

Objectives:To study knowledge and attitudes of hospital ethics committee members at the first workshop for ethics committees in Croatia.Design:Before/after cross-sectional study using a self administered questionnaire.Setting:Educational workshop for members of hospital ethics committees, Zagreb, 2003.Main outcome measurements:Knowledge and attitudes of participants before and after the workshop; everyday functioning of hospital ethics committees.Results:The majority of the respondents came from committees with at least five members. The majority of ethics committees were appointed by the governing bodies of their hospitals. Most committees were founded after the implementation of the law on health protection in 1997. Membership structure (three physicians and two members from other fields) and functions were established on the basis of that law. Analysis of research protocols was the main part of their work. Other important functions—education, case analysis, guidelines formation—were neglected. Members’ level of knowledge was not sufficient for the complicated tasks they were supposed to perform. However, it was significantly higher after the workshop. Most respondents felt their knowledge should be improved by additional education. Their views on certain issues and bioethical dilemmas displayed a high level of paternalism and over protectiveness, which did not change after the workshop.Conclusions:The committees developed according to bureaucratic requirements. Furthermore, there are concerns about members’ knowledge levels. More efforts need to be made to use education to improve the quality of the work. Additional research is necessary to explore ethics committees’ work in Croatia especially in the hospital setting.