bluuebunny/crossref_metadata_2025 huggingface dataset:
Charge localization in alcohol isomers studied by Compton scattering
Authors: Hakala M. , Nygård K. , Vaara J. , Itou M. , Sakurai Y. , Hämäläinen K.
Published: January 2009

The isomers of small molecule alcohols propanol (PrOH) and butanol (BuOH) are studied by x-ray Compton scattering experiments with synchrotron radiation and density-functional theory calculations. The lineshape of the measured spectra, i.e., the Compton profile, is a momentum-space property, and its changes reflect changes in the electronic charge density between the isomers. Compared to the linear alcohols (n-PrOH and n-BuOH), the Compton profiles of the branched alcohols (iso-PrOH, iso-BuOH, sec-BuOH) are found to be narrower, which indicates a more delocalized charge for the latter. The calculations are performed for systems consisting of one to three monomer units and are found to reproduce reasonably the experimental spectral features. The influence of the basis set and exchange-correlation scheme is studied in more detail. The results provide new insight into the isomeric differences in small molecule alcohols and show that quantum chemical calculations can be increasingly tested against the x-ray Compton scattering data.
Constrained density functional theory based configuration interaction improves the prediction of reaction barrier heights
Authors: Wu Qin , Kaduk Benjamin , Van Voorhis Troy
Published: January 2009

In this work, a constrained density functional theory based configuration interaction approach (CDFT-CI) is applied to calculating transition state energies of chemical reactions that involve bond forming and breaking at the same time. At a given point along the reaction path, the configuration space is spanned by two diabaticlike configurations: reactant and product. Each configuration is constructed self-consistently with spin and charge constraints to maximally retain the identities of the reactants or the products. Finally, the total energy is obtained by diagonalizing an effective Hamiltonian constructed in the basis spanned by these two configurations. By design, this prescription does not affect the energies of the reactant or product species but will affect the energy at intermediate points along the reaction coordinate, most notably by modifying the reaction barrier height. When tested with a large set of reactions that include hydrogen transfer, heavy atom transfer, and nucleophilic substitution, CDFT-CI is found to improve the prediction of barrier heights by a factor of 2–3 for some commonly used local, semilocal, and hybrid functionals. Thus, just as CDFT can be used to cure energy errors in charge localized states, CDFT-CI can recover the correct energy for charge delocalized states by approximating the true wave function as a linear combination of localized configurations (e.g., reactant and product). The well-defined procedure and the promising results of CDFT-CI suggest that it could broaden the applicability of traditional DFT methods for reaction barrier heights.
Free-time and fixed end-point optimal control theory in quantum mechanics: Application to entanglement generation
Authors: Mishima K. , Yamashita K.
Published: January 2009

We have constructed free-time and fixed end-point optimal control theory for quantum systems and applied it to entanglement generation between rotational modes of two polar molecules coupled by dipole-dipole interaction. The motivation of the present work is to solve optimal control problems more flexibly by extending the popular fixed time and fixed end-point optimal control theory for quantum systems to free-time and fixed end-point optimal control theory. As a demonstration, the theory that we have constructed in this paper will be applied to entanglement generation in rotational modes of NaCl–NaBr polar molecular systems that are sensitive to the strength of entangling interactions. Our method will significantly be useful for the quantum control of nonlocal interaction such as entangling interaction, which depends crucially on the strength of the interaction or the distance between the two molecules, and other general quantum dynamics, chemical reactions, and so on.
On the interactions between molecules in an off-resonant laser beam: Evaluating the response to energy migration and optically induced pair forces
Authors: Andrews David L. , Leeder Jamie M.
Published: January 2009

Electronically excited molecules interact with their neighbors differently from their ground-state counterparts. Any migration of the excitation between molecules can modify intermolecular forces, reflecting changes to a local potential energy landscape. It emerges that throughput off-resonant radiation can also produce significant additional effects. The context for the present analysis of the mechanisms is a range of chemical and physical processes that fundamentally depend on intermolecular interactions resulting from second and fourth-order electric-dipole couplings. The most familiar are static dipole-dipole interactions, resonance energy transfer (both second-order interactions), and dispersion forces (fourth order). For neighboring molecules subjected to off-resonant light, additional forms of intermolecular interaction arise in the fourth order, including radiation-induced energy transfer and optical binding. Here, in a quantum electrodynamical formulation, these phenomena are cast in a unified description that establishes their inter-relationship and connectivity at a fundamental level. Theory is then developed for systems in which the interplay of these forms of interaction can be readily identified and analyzed in terms of dynamical behavior. The results are potentially significant in Förster measurements of conformational change and in the operation of microelectromechanical and nanoelectromechanical devices.
Vibrationally inelastic collisions of H+D2: A comparison of quantum mechanical, quasiclassical, and experimental results
Authors: Jambrina P. G. , Aldegunde J. , Castillo J. F. , Aoiz F. J. , Sáez Rábanos V.
Published: January 2009

A detailed comparison of quantum mechanical (QM) and quasiclassical trajectory (QCT) integral and differential cross sections (DCSs) as well as opacity functions is presented in this work for the vibrationally inelastic collisions of H+D2(v=0,j=0)→H+D2(v′=3,j′) at 1.72 eV collision energy. These results are also compared with the experimental differential cross sections by Greaves et al. [Nature (London) 454, 88 (2008)]. The agreement between QCT and QM results is fairly good but some differences are appreciable, and it is shown that the experimental results are in a somewhat better agreement with the calculated QM DCS. The present results and their analysis confirm that the vibrational excitation takes place by elongation of the D–D bond in a “tug-of-war” mechanism, where the incoming H atom and one of the D atoms compete for the formation of a bond with the other D atom, as proposed by Greaves et al. It is also found that these collisions may give rise to the formation of short-lived collision complexes (τcoll=35–50 fs) that can be traced back to the presence of relatively deep wells in the potential surface when the original D–D bond is stretched. The analysis of the trajectories into v′=3 reveals that most of them cross at least twice the reaction barrier via a recrossing mechanism.
Dimethyldioxirane Oxidation of Exocyclic (E,E)-Cinnamylideneketones
Authors: Lévai Albert , Silva Artur M. S. , Santos Clementina M. M. , Cavaleiro José A. S. , Jekő József
Published: January 2009

Exocyclic (E,E)-cinnamylideneketones were oxidized by an excess of isolated dimethyldioxirane (DMDO, in acetone solution) at room temperature, providing diastereomeric mixtures of the α,β:γ,δ-diepoxides. In the case of derivatives bearing an ortho-nitrocinnamylidene moiety, α,β-monoepoxides were also isolated as minor products. The structures of all new compounds and the stereochemistry of the monoepoxides and diepoxide diastereomers were established by NMR studies.
A Strategic, 'Green' Approach to Organic Chemistry with Microwave Assistance and Predictive Yield Optimization as Core, Enabling Technologies
Authors: Strauss Christopher R.
Published: January 2009

Since 1988, we have pursued enabling technologies and methods as tools for ‘green’ synthetic chemistry. The developed technologies comprise hardware including catalytic membranes and continuous and batch microwave reactors that have established global markets, as well as interactive, predictive software for optimization of yields and translation of conditions. New methods include ‘green’ reactions such as a catalytic symmetrical etherification, Pd-catalyzed coupling processes and a multi-component cascade for aniline derivatives. Reactions and workup were facilitated through solvent-free conditions, aqueous media at high temperature and dimethylammonium dimethylcarbamate (dimcarb) as a ‘distillable’ protic ionic liquid, as well as by non-extractive techniques for product isolation. The technologies and methods were designed for use alone or in various combinations as desired. Consolidation of individual operations or processes into unit steps was achieved through multi-tasking: media, reactants, catalysts, and conditions were selected to serve several purposes at various stages of a reaction. The tools were used to establish a technology platform comprising structurally diverse oligomers, macrocycles, and rod-like molecules supplementary to those available through phenol-formaldehyde chemistry. Dienone precursors were assembled from versatile building blocks containing complementary ‘male’ or ‘female’ fittings that were connected through inherently ‘green’ Claisen–Schmidt-type reactions. Isoaromatization afforded Horning-crowns, macrocyclic phenolic derivatives that were hybrids of calixarenes and crown ethers. Preliminary studies of organic substrates in salt water, with and without CO2, called into question proposals for disposal of anthropogenic CO2 by deep-sea dispersal.
Population dynamics of large and small mammals: Graeme Caughley's grand vision
Authors: Krebs Charles J.
Published: January 2009

Ecologists that study the population dynamics of large and small herbivorous mammals operate in two worlds that overlap only partly, and in this paper I address whether the conjecture that these worlds represent two distinct and valid paradigms is currently justified. I argue that large mammals fall into three groups depending on whether they have effective predators or not, and whether they are harvested by humans. Because of human persecution of large predators, more and more large herbivorous mammals are effectively predator-free and are controlled bottom-up by food. But in less disturbed systems, large herbivorous mammals should be controlled top-down by effective predators, and this can lead to a trophic cascade. Small herbivorous mammals have been suggested to be controlled top-down by predators but some experimental evidence has challenged this idea and replaced it with the notion that predation is one of several factors that may affect rates of population increase. Intrinsic control (territoriality, infanticide, social inhibition of breeding) appears to be common in small herbivorous mammals with altricial young but is absent in species with precocial young, in ecosystems with strong stochastic weather variation (deserts) and in areas of human-induced habitat fragmentation in agricultural monocultures. The extrinsic control of large herbivores with precocial young validates part of Graeme Caughley’s Grand Vision, but the relative role of intrinsic and extrinsic mechanisms for small herbivores with altricial young is still controversial. An improved knowledge of population control mechanisms for large and small herbivores is essential for natural resource management.
Advances in wildlife ecology and the influence of Graeme Caughley
Authors: Sinclair A. R. E. , Metzger Kristine L.
Published: January 2009

Graeme Caughley produced substantial advances in our understanding of interactions between large mammalian herbivores and the environments they occupy. The strength of his work lay in the logical approach to answering fundamental questions. While his life work contributed to our understanding of animal population dynamics, it is in the application of his research and ideas that we have greatly advanced the science of conservation biology. Two central legacies of Caughley’s lifelong work are that an understanding of basic science leads to more appropriate management, and that underlying assumptions must be explicitly stated and tested. By arguing that efficient management of ecosystems requires an understanding of the underlying mechanisms, he moved forward the application of basic research to management. Future advances in wildlife conservation must focus on three aspects: (1) the rules for stability in ecosystems, and how humans cause instability; (2) the decline in native habitats, mostly from agriculture, and how to renew and reconstruct them while expanding threatened populations; and (3) how to breed species in captivity, and then reintroduce them as a last line of defence.
Graeme Caughley and the fundamentals of population ecology: a personal view
Authors: Sibly Richard M.
Published: January 2009

Caughley’s contributions to single-species population ecology are here discussed in the light of some of the ideas and studies his work elicited, with particular reference to influences on my own work and that of my collaborators. Major themes are the manner and extent of population regulation; the alternate perspectives on population regulation that are obtained by density-dependence analyses and mechanistic analyses in terms of food availability and other causal factors; and ways in which mechanistic analyses can be elaborated to characterise a species’ ecological niche and relate it to the species’ geographic range.
Expansion of radiofrequency ablation volume by saturated NaCL saline injection in the area of vaporization
Authors: Shimizu A. , Ishizaka H. , Awata S. , Shiraishi A. , Hirasawa S. , Tatezawa T. , Kano M. , Shimodaira K. , Taketomi-Takahashi A. , Tsushima Y. , Endo K.
Published: January 2009

Background: Vaporization around the radiofrequency (RF) electrode after RF application (RFA) limits the RF ablation area.

Purpose: To determine whether saturated saline injected into the area of vaporization after initial RFA extends ablation area after further RFA.

Material and Methods: RFA was performed in 18 ex vivo porcine livers and four in vivo rabbit erector spinae muscles. An RF electrode was used to ablate an area with 40W of parallel current for 15 min. The ablation margin was determined using a thermocouple, and the radius of the ablated area was measured. After RF electrode removal, saturated saline was infused through a percutaneous ethanol injection needle into the site of the original RFA in 11 liver samples and two erector spinae muscles. Three minutes later, RFA was resumed for 15 min. The remaining seven control liver samples and two spinae muscles received RFA without saline injection. The radius of the final ablated area was then measured.

Results: In the ex vivo study, injection of saturated saline significantly decreased tissue impedance (87.7±9.4 to 51.1±9.7Ω, P<0.0001), and increased the mean radius of the ablated area (15.9±3.0 to 25.0±3.6 mm, P<0.0001). These significant changes were not observed without injection of saturated saline. Similar trends were found in the in vivo study.

Conclusion: Injection of saturated saline into the area of vaporization around the RF electrode, followed by additional RFA, caused concentric expansion of the final ablation area, facilitating more efficient tumor ablation.
BEYOND HIERARCHICAL REPRESENTATIONS OF THE FORMAL/INFORMAL EMPLOYMENT DUALISM
Authors: Williams Colin C. , Round John
Published: January 2009

This paper evaluates critically the conventional hierarchical representation of the formal/informal employment dualism, which depicts formal employment as extensive and positively contributing to economic development and social cohesion, and the separate realm of informal employment as weaker, inhabiting the margins and impairing progress and development. Although the discourses of informal employment as weak, marginal and separate from formal employment have been previously put under the spotlight, there has been little questioning of whether informal employment is a negative phenomenon. Through a study of Ukraine, however, this paper finds evidence that informal employment positively contributes to not only economic development as a seedbed for enterprise and entrepreneurship but also social cohesion as a primary vehicle for delivering community self-help. The outcome is a call for a finer-grained understanding of informal (and ultimately also formal) employment that recognises its plurality of forms and their varying consequences for economic development and social cohesion.
CONCENTRATION OF WORKING-AGE MALE MORTALITY AMONG MANUAL WORKERS IN URBAN LATVIA AND RUSSIA, 1970–1989
Authors: Andreev Evgueni , Hoffmann Rasmus , Carlson Elwood , Shkolnikov Vladimir , Kharkova Tatiana L.
Published: January 2009

Until recently data on mortality by socioeconomic status were not available for the initial period of mortality increase in the former Soviet Union from 1965 to 1979. Newly discovered data from the Russian State Archive of Economics allow us to close this gap and to compare mortality trends in urban Latvia and several urban areas of Russia with the concentration of rising male mortality among manual workers already found in several eastern European countries. A similar trend appears in these data for rising mortality to concentrate among manual workers over time. Unfavorable trends in the life expectancy of the total population were largely driven by mortality increase among manual workers. Possible determinants of the pattern include a special type of economic growth in the USSR in the 1970s and 1980s associated with dominance of heavy industries and military sector, and low consumer goods’ production, high prevalence of hard manual labor, massive rural–urban migrations and poor living conditions of new coming industrial workers, growing psychosocial stress and high prevalence of adverse health behaviors. These characteristics are discussed in the framework of an incomplete modernization and distinct health life styles in state socialist countries.
Rationality of the Folsom-Ono grid
Authors: Guerzhoy P.
Published: January 2009

In a recent paper Folsom and Ono constructed a grid of Poincaré series of weights

3

/

2

3/2

and

1

/

2

1/2

. They conjectured that the coefficients of the holomorphic parts of these series are rational integers. We prove that these coefficients are indeed rational numbers with bounded denominators.
An upper bound on the characteristic polynomial of a nonnegative matrix leading to a proof of the Boyle-Handelman conjecture
Authors: Goldberger Assaf , Neumann Michael
Published: January 2009

In their celebrated 1991 paper on the inverse eigenvalue problem for nonnegative matrices, Boyle and Handelman conjectured that if

A
A

is an

(
n
+
1
)
×
(
n
+
1
)

(n+1)\times (n+1)

nonnegative matrix whose nonzero eigenvalues are:

λ
0

≥

|

λ
i

|

\lambda _0 \geq |\lambda _i|

,

i
=
1
,
…
,
r

i=1,\ldots ,r

,

r
≤
 
n

r \leq \ n

, then for all

x
≥

λ
0

x \geq \lambda _0

,
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="StartLayout 1st Row with Label left-parenthesis asterisk right-parenthesis EndLabel product Underscript i equals 0 Overscript r Endscripts left-parenthesis x minus lamda Subscript i Baseline right-parenthesis less-than-or-equal-to x Superscript r plus 1 Baseline minus lamda 0 Superscript r plus 1 Baseline period EndLayout">

(
∗
)

∏

i
=
0

r

(
x
−

λ
i

)
≤

x

r
+
1

−

λ
0

r
+
1

.

\begin{equation} \prod _{i=0}^{r} (x-\lambda _i) \leq x^{r+1}-\lambda _0^{r+1}.\tag *{$(\ast )$} \end{equation}

To date the status of this conjecture is that Ambikkumar and Drury (1997) showed that the conjecture is true when

2
(
r
+
1
)
≥
(
n
+
1
)

2(r+1)\geq (n+1)

, while Koltracht, Neumann, and Xiao (1993) showed that the conjecture is true when

n
≤
4

n\leq 4

and when the spectrum of

A
A

is real. They also showed that the conjecture is asymptotically true with the dimension.

Here we prove a slightly stronger inequality than in

(
∗
)

(\ast )

, from which it follows that the Boyle–Handelman conjecture is true. Actually, we do not start from the assumption that the

λ
i

\lambda _i

’s are eigenvalues of a nonnegative matrix, but that

λ
1

,
…
,

λ

r
+
1

\lambda _1,\ldots , \lambda _{r+1}

satisfy

λ
0

≥

|

λ
i

|

\lambda _0\geq |\lambda _i|

,

i
=
1
,
…
,
r

i=1,\ldots , r

, and the trace conditions:
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="StartLayout 1st Row with Label left-parenthesis asterisk asterisk right-parenthesis EndLabel sigma-summation Underscript i equals 0 Overscript r Endscripts lamda Subscript i Superscript k Baseline greater-than-or-equal-to 0 comma for all k greater-than-or-equal-to 1 period EndLayout">

(
∗
∗
)

∑

i
=
0

r

λ
i
k

≥
0
,
 

for all

k
≥
1.

\begin{equation} \sum _{i=0}^{r} \lambda _i^k \geq 0, \ \mbox {for all} k \geq 1.\tag *{$(\ast \ast )$} \end{equation}

A strong form of the Boyle–Handelman conjecture, conjectured in 2002 by the present authors, says that (

∗
*

) continues to hold if the trace inequalities in (

∗
∗

**

) hold only for

k
=
1
,
…
,
r

k=1,\ldots ,r

. We further improve here on earlier results of the authors concerning this stronger form of the Boyle–Handelman conjecture.
On period minimal pseudo-Anosov braids
Authors: de Carvalho André , Hall Toby , Venzke Rupert
Published: January 2009

A family of period minimal pseudo-Anosov braids, one for each pair of Farey neighbors in

(
0
,
1

/

2
]

(0,1/2]

, is described.
Optimization of the first eigenvalue in problems involving the 𝑝-Laplacian
Authors: Cuccu Fabrizio , Emamizadeh Behrouz , Porru Giovanni
Published: January 2009

This paper concerns minimization and maximization of the first eigenvalue in problems involving the

p
p

-Laplacian, under homogeneous Dirichlet boundary conditions. Physically, in the case of

N
=
2

N=2

and

p
p

close to

2
2

, our equation models the vibration of a nonhomogeneous membrane

Ω
\Omega

which is fixed along the boundary. Given several materials (with different densities) of total extension

|

Ω

|

|\Omega |

, we investigate the location of these material inside

Ω
\Omega

so as to minimize or maximize the first mode in the vibration of the membrane.
Audit of Management of Acute Infective Conjunctivitis in Primary Care
Authors: Knights Gayle
Published: January 2009

A recent article in the British Medical Journal ( Everitt et al., 2006 ), looking at various options for the management of uncomplicated acute infective conjunctivitis (AIC), suggested that a delayed prescription of anti-infective eye preparations was the most appropriate choice. Up to this point, I routinely prescribed chloramphenicol or fusidic acid for all patients presenting with AIC and the partners at my practice agreed their management approach was the same as mine. A literature search of Medline, Cochrane Library and BMJ.com , using search strings ‘infective conjunctivitis’, ‘delayed prescribing’ and ‘conjunctivitis-delayed prescribing’ revealed further evidence for withholding treatment.
Modern Records, New Challenges
Authors: Gillian Braunold
Published: January 2009

Our clinical records are changing. The familiar world of a patient's record being kept by a general practice with no links to the outside world has already passed. New ways of working are arriving on our desktops daily. This paper looks at the implications of these changes.
Implications of Pathogenesis by Erwinia amylovora on Rosaceous Stigmas to Biological Control of Fire Blight
Authors: Johnson K. B. , Sawyer T. L. , Stockwell V. O. , Temple T. N.
Published: January 2009

As a prerequisite to infection of flowers, Erwinia amylovora grows epiphytically on stigmas, which provide a conducive habitat for bacterial growth. Stigmas also support growth of several other bacterial genera, which allows for biological control of fire blight; although, in practice, it is very difficult to exclude E. amylovora completely from this habitat. We investigated the dynamics of growth suppression of E. amylovora by comparing the ability of virulent and avirulent strains of E. amylovora to compete with each other on stigmas of pear, apple, and blackberry, and to compete with a co-inoculated mixture of effective bacterial antagonists. When strains were inoculated individually, virulent E. amylovora strain Ea153N attained the highest population size on stigmas, with population sizes that were approximately double those of an avirulent hrpL mutant of Ea153 or the bacterial antagonists. In competition experiments, growth of the avirulent derivative was suppressed by the antagonist mixture to a greater extent than the virulent strain. Unexpectedly, the virulent strain enhanced the population size of the antagonist mixture. Similarly, a small dose of virulent Ea153N added to inoculum of an avirulent hrpL mutant of Ea153 significantly increased the population size of the avirulent strain. A pathogenesis-gene reporter strain, Ea153 dspE::gfp, was applied to flowers and a subset of the population expressed the green fluorescent protein while growing epiphytically on stigmas of apple. These results are consistent with the hypothesis that virulent E. amylovora modifies the epiphytic habitat presented by the stigma through a pathogenesis-related process, which increases host resources available to itself and, coincidentally, to nonpathogenic competitors. Over nine orchard trials, avirulent Ea153 hrpL significantly suppressed the incidence of fire blight four times compared with six for the antagonist mixture. The degree of biological control achievable with an avirulent strain of E. amylovora likely is limited by its inability to utilize the stigmatic habitat to the same degree as a virulent strain.
Genetic Loci Involved in Rubrifacine Production in the Walnut PathogenBrenneria rubrifaciens
Authors: McClean Ali E. , Kluepfel Daniel A.
Published: January 2009

Brenneria rubrifaciens produces a unique red pigment known as rubrifacine that has been hypothesized to play a role in pathogenesis on walnut. Analysis of DNA flanking the Tn5 insertion site in 20 rubrifacine minus (pig–) mutants identified three regions required for rubrifacine production. The first region was homologous to nonribosomal peptide synthetases (NRPS), the second was homologous to autoinducer synthase genes (expI homologs), and the third region was homologous to the slyA gene of Candidatus blochmania and Escherichia coli. Pigment production was not necessary for elicitation of the hypersensitive response (HR) in tobacco and had little impact on virulence in tissue-cultured walnut plants. The expI-interrupted mutants exhibited reduced virulence on walnut and were HR negative on tobacco. Pigment production was restored in Br-212 when grown in the presence of wild-type B. rubrifaciens, E. coli carrying the cloned expI-like gene, or introduction of the cloned wild-type copy of the expI-like gene. Two Brenneria spp., B. nigrifluens and B. salicis, also restored pigment production in Br-212. These results demonstrate that rubrifacine production and virulence of B. rubrifaciens on walnut are under the control of a quorum-sensing system and are sensitive to signal molecules from other Brenneria spp.
Inoculum Availability and Conidial Dispersal Patterns of Fusarium mangiferae, the Causal Agent of Mango Malformation Disease
Authors: Gamliel-Atinsky E. , Sztejnberg A. , Maymon M. , Shtienberg D. , Freeman S.
Published: January 2009

Inoculum availability and conidial dispersal patterns of Fusarium mangiferae, causal agent of mango malformation disease, were studied during 2006 and 2007 in an experimental orchard. The spatial pattern of primary infections in a heavily infected commercial mango orchard corresponded with a typical dispersal pattern caused by airborne propagules. Malformed inflorescences were first observed in mid-March, gradually increased, reaching a peak in May, and declined to negligible levels in August. The sporulation capacity of the malformed inflorescences was evaluated during three consecutive months. Significantly higher numbers of conidia per gram of malformed inflorescence were detected in May and June than in April. Annual conidial dissemination patterns were evaluated by active and passive trapping of conidia. A peak in trapped airborne conidia was detected in May and June for both years. The daily pattern of conidial dispersal was not associated with a specifically discernable time of day, and an exponential correlation was determined between mean relative humidity (RH) and mean number of trapped conidia. Higher numbers of conidia were trapped when RH values were low (<55%). This is the first detailed report on airborne dispersal of F. mangiferae, serving as the primary means of inoculum spread.
Real-Time Quantitative Expression Studies of the Zearalenone Biosynthetic Gene Cluster in Fusarium graminearum
Authors: Lysøe Erik , Bone Karen R. , Klemsdal Sonja S.
Published: January 2009

The estrogenic mycotoxin zearalenone (ZON) produced by some Fusarium spp. causes reproductive problems and hyperestrogenic syndromes in mammals. In an effort to elucidate the molecular pathways of ZON production, we present a comparative real-time quantitative polymerase chain reaction expression study of seven contiguous genes in the ZON biosynthetic cluster on sterile rice and during wheat and oat infection. Under ZON production on rice, the polyketide synthase (PKS) genes PKS4 and PKS13, alcohol oxidase FG12056 gene, and transcriptional regulator FG02398 gene showed similarly upregulated patterns, whereas the nonribosomal peptide synthetase (NPS) FG02394, the K+ channel β subunit FG12015, and the protein kinase FG02399 displayed a variant pattern. During the same time period under wheat infection when no ZON was produced, the PKS genes and the NPS were downregulated relative to rice whereas the K+ channel β subunit gene FG12015 was markedly upregulated, suggesting that it may play a role in the infection process. This is the first expression study of ZON biosynthetic genes in planta. The results give insight into the regulation and activities of the ZON gene cluster under different experimental systems and suggest a connection between ZON and a K+ channel that could reveal a novel function for ZON in Fusarium spp.
Identification and Characterization of the Most Abundant Cellulases in Stylet Secretions from Globodera rostochiensis
Authors: Rehman Sajid , Butterbach Patrick , Popeijus Herman , Overmars Hein , Davis Eric L. , Jones John T. , Goverse Aska , Bakker Jaap , Smant Geert
Published: January 2009

Plant-parasitic cyst nematodes secrete cell wall modifying proteins during their invasion of host plants. In this study, we used a monoclonal antibody to immunopurify and to sequence the N terminus of the most abundant cellulases in stylet secretions of preparasitic juveniles of Globodera rostochiensis. The N-terminal amino acid sequence perfectly matched the sequence of an expressed sequence tag of two nearly identical genes, named Gr-eng3 and Gr-eng4, which show relatively low similarity with the previously identified Gr-eng1 and Gr-eng2 (i.e., 62% similarity and 42% identity). The recombinantly produced proteins from Gr-eng3 and Gr-eng4 demonstrated specific activity on carboxymethylcellulose, indicating that these genes encode active cellulases. To date, the cellulases in cyst nematodes are comprised of three possible domain structure variants with different types of ancillary domains at the C terminus of the glycosyl hydrolase family 5 (GHF5) domain. We used Bayesian inference to show that the phylogeny of the GHF5 domain based on currently available data suggest that the extant nematode cellulases arose through reshuffling of the GHF5 domain with different types of ancillary domains as relatively independent units. Knocking-down Gr-eng3 and Gr-eng4 using RNA interference resulted in a reduction of nematode infectivity by 57%. Our observations show that the reduced infectivity of the nematodes can be attributed to poor penetration of the host's root system at the onset of parasitism.
AER1, a Major Gene Conferring Resistance to Aphanomyces euteiches in Medicago truncatula
Authors: Pilet-Nayel M.-L. , Prospéri J.-M. , Hamon C. , Lesné A. , Lecointe R. , Le Goff I. , Hervé M. , Deniot G. , Delalande M. , Huguet T. , Jacquet C. , Baranger A.
Published: January 2009

Aphanomyces euteiches is a major soilborne oomycete pathogen that infects various legume species, including pea and alfalfa. The model legume Medicago truncatula has recently emerged as a valuable genetic system for understanding the genetic basis of resistance to A. euteiches in leguminous crops. The objective of this study was to identify genetic determinants of resistance to a broad host-range pea-infecting strain of A. euteiches in M. truncatula. Two M. truncatula segregating populations of 178 F5 recombinant inbred lines and 200 F3 families from the cross F83005.5 (susceptible) × DZA045.5 (resistant) were screened for resistance to A. euteiches. Phenotypic distributions observed suggested a dominant monogenic control of resistance. A major locus associated with resistance to A. euteiches, namely AER1, was mapped by bulk segregant analysis to a terminal end of chromosome 3 in M. truncatula and explained 88% of the phenotypic variation. AER1 was identified in a resistance-gene-rich region, where resistance gene analogs and genes associated with disease resistance phenotypes have been identified. Discovery of AER1 opens up new prospects for improving resistance to A. euteiches in cultivated legumes using a comparative genomics approach.
Repression of Seed Maturation Genes by a Trihelix Transcriptional Repressor inArabidopsisSeedlings
Authors: Gao Ming-Jun , Lydiate Derek J. , Li Xiang , Lui Helen , Gjetvaj Branimir , Hegedus Dwayne D. , Rozwadowski Kevin
Published: January 2009

The seed maturation program is repressed during germination and seedling development so that embryonic genes are not expressed in vegetative organs. Here, we describe a regulator that represses the expression of embryonic seed maturation genes in vegetative tissues. ASIL1 (for Arabidopsis 6b-interacting protein 1-like 1) was isolated by its interaction with the Arabidopsis thaliana 2S3 promoter. ASIL1 possesses domains conserved in the plant-specific trihelix family of DNA binding proteins and belongs to a subfamily of 6b-interacting protein 1-like factors. The seedlings of asil1 mutants exhibited a global shift in gene expression to a profile resembling late embryogenesis. LEAFY COTYLEDON1 and 2 were markedly derepressed during early germination, as was a large subset of seed maturation genes, such as those encoding seed storage proteins and oleosins, in seedlings of asil1 mutants. Consistent with this, asil1 seedlings accumulated 2S albumin and oil with a fatty acid composition similar to that of seed-derived lipid. Moreover, ASIL1 specifically recognized a GT element that overlaps the G-box and is in close proximity to the RY repeats of the 2S promoters. We suggest that ASIL1 targets GT-box–containing embryonic genes by competing with the binding of transcriptional activators to this promoter region.
Bias and conflict in phylogenetic inference of myco‐heterotrophic plants: a case study in Thismiaceae
Authors: Merckx Vincent , Bakker Freek T. , Huysmans Suzy , Smets Erik
Published: January 2009

Due to morphological reduction and absence of amplifiable plastid genes, the identification of photosynthetic relatives of heterotrophic plants is problematic. Although nuclear and mitochondrial gene sequences may offer a welcome alternative source of phylogenetic markers, the presence of rate heterogeneity in these genes may introduce bias/systematic error in phylogenetic analyses. We examine the phylogenetic position of Thismiaceae based on nuclear 18S rDNA and mitochondrial atpA DNA sequence data, as well as using parsimony, likelihood and Bayesian inference methods. Significant differences in evolutionary rates of these genes between closely related taxa lead to conflicting results: while parsimony analyses of 18S rDNA and combined data strongly support the monophyly of Thismiaceae, Bayesian inference, with and without a relaxed molecular clock, as well as the Swofford–Olsen–Waddell–Hillis (SOWH) test confidently reject this hypothesis. We show that rate heterogeneity in our data leads to long‐branch attraction artifacts in parsimony analysis. However, using model‐based inference methods the question of whether Thismiaceae are monophyletic remains elusive. On the one hand maximum likelihood nonparametric bootstrapping and parametric hypothesis tests fail to support a paraphyletic Thismiaceae, on the other hand Bayesian inference methods (both without and with a relaxed clock) significantly reject a monophyletic Thismiaceae. These results show that an adequate sampling, the use of rate homogeneous data, and the application of different inference methods are important factors for developing phylogenetic hypotheses of myco‐heterotrophic plants. © The Willi Hennig Society 2009.
Secondary chemistry and ribosomal DNA data congruencies in Arnica (Asteraceae)
Authors: Ekenäs Catarina , Rosén Josefin , Wagner Steffen , Merfort Irmgard , Backlund Anders , Andreasen Katarina
Published: January 2009

To investigate possible congruencies between DNA sequence data and secondary chemistry, we compared nuclear ribosomal DNA (nrDNA) sequence data, sesquiterpene lactone (STL) contents, and cytometric data from 35 accessions of 16 Arnica (Asteraceae) species and two outgroup taxa (Layia hieracioides and Madia sativa), using phylogenetic inference and principal component analysis (PCA). Several groups supporting multiple accessions of the same species (of A. montana, A. longifolia, A. gracilis, and A. chamissonis) are congruent between the phylogenetic trees based on nrDNA and STL data. Sesquiterpene lactone profiles were found to be highly consistent within multiple samples of A. montana and A. longifolia respectively. Moreover, sesquiterpene lactone data support subspecies classifications of A. chamissonis and A. parryi, with additional support from DNA sequence data and cytometric data. Morphology, STL data (PCA), cytometric data and DNA sequence data suggest a hybrid origin of one accession (A. gracilis × longifolia). In A. gracilis, A. latifolia, and Layia hieracioides, previously not investigated for STLs, we found large amounts of xanthalongin derivatives. This is the first time STLs have been reported from subtribe Madiinae.

© The Willi Hennig Society 2009.
Children as Public Actors: Navigating the Tensions
Authors: Shier Harry
Published: January 2009

Drawing on comparative research with children’s participation practitioners in Nicaragua and the United Kingdom, this study explores the thinking that guides their practice. Earlier models are considered inadequate to describe complex, multidimensional participation processes. Whilst several differences are observed, the key issues or tensions are similar in both countries. Fifteen tensions are discussed in three categories. Most are tensions between participation as social control and participation as empowerment, which apply to all marginalised groups, not just children. The second group is specific to children. Finally, there are tensions between process and product. It is suggested that practitioners could use this analysis to reappraise and improve practice.
Framing the Picture of the Child
Authors: Alasuutari Maarit , Karila Kirsti
Published: January 2009

The paper studies the forms that are used in planning for a child’s early childhood education and care in Finnish day care from the perspectives of social constructionism and discourse analysis. It asks how childhood is conceptualised in these forms and what are the social functions of early childhood education and care as implied in the conceptualisations. The paper shows that the conceptions of childhood and the understanding of the functions of early childhood education and care are mostly in unison and are rooted in traditional discourses, approaches and practices of Finnish day care. Consequently, the child’s view and the child as an agent in her/his world are not present in the forms.
Listening to Children in Care: A Review of Methodological and Theoretical Approaches to Understanding Looked after Children’s Perspectives
Authors: Holland Sally
Published: January 2009

This article reviews 44 refereed journal articles published between 2003 and 2008. All of the articles attempt to directly uncover the experiences or perspectives of young people cared for by the state in foster, residential or kinship care homes. The review reveals that this field is developing a rich body of evidence derived from a broad range of methodological and theoretical frameworks. In this sample, research designs appeared to be influenced by placement settings, as well as theoretical orientations, but comparative and longitudinal designs were used in both quantitative and qualitative studies. Participative research designs were only present in qualitative designs within a broadly interpretive theoretical orientation. It is suggested in this article that researchers should critically reflect on the use of constructs that may negatively label young people in care. It is also suggested that there could be fuller reporting of ethical issues. Despite some identified gaps, such as the participation of young people in quantitative research designs and research with younger age groups, the article concludes that there appears to be an encouraging emergence of theoretical and methodological diversity in this research area.
Immunolocalization and serum antibody responses to Brugia malayi pepsin inhibitor homolog (Bm‐33)
Authors: Krushna Nagampalli S. A. , Shiny Chandanpurath , Dharanya Srinivasan , Sindhu Arivazhagan , Aishwarya Sridharan , Narayanan Rangarajan B.
Published: January 2009

cDNA coding for Brugia malayi pepsin inhibitor homolog (Bm‐33) from the human filarial parasite was cloned in pRSET for large‐scale expression and functional characterization. The pRSET‐B cloned gene did not yield recombinant protein expression and the reason was attributed to the presence of an N‐terminal signal peptide. The gene was subcloned in pRSET‐A without a signal peptide and the 33 kDa histidine‐tagged recombinant protein was purified by IMAC. All individuals from an endemic area generated IgG responses against Bm‐33 in the order MF>CP>EN. Isotype analysis indicated an elevated IgG4 reactivity in the order MF>EN>CP. Bm‐33‐specific IgE levels were elevated in MF, CP and EN compared to non‐endemic normals with no significant differences among the groups. Paraffin‐embedded sections of Setaria digitata (cattle filarial parasite) stained with mouse anti‐Bm‐33 antibodies exhibited the hypodermal nature of Bm‐33. These findings suggest that Bm‐33 is an immunodominant antigen and contributes to filarial pathogenesis.
Prevalence and characteristics of cytolethal distending toxin‐producing Escherichia coli from children with diarrhea in Japan
Authors: Hinenoya Atsushi , Naigita Akira , Ninomiya Keiko , Asakura Masahiro , Shima Kensuke , Seto Kazuko , Tsukamoto Teizo , Ramamurthy T. , Faruque Shah M. , Yamasaki Shinji
Published: January 2009

In the present study, we examined the prevalence and characteristics of CTEC among diarrheal children in Japan during a year‐long surveillance study. A PCR‐RFLP assay for the detection and differentiation of five types of E. coli cdtB gene (types I through V) was developed, and 362 stool specimens collected from patients reporting to pediatric departments in two hospitals were analyzed. Of the 35 samples (9.7%) that were positive for the cdtB gene, 21 were positive for cdt‐I, three for cdt‐II, four for cdt‐III, three for cdt‐IV and four samples were positive for cdt‐V, as determined by different molecular techniques. The recovery of CTEC having cdt alleles was a little less, which included 19 with cdt‐I, one cdt‐II, three cdt‐III, three cdt‐IV and four with cdt‐V. Among 30 CTEC strains isolated, the majority of them (43%) belonged to serogroup O2. The other virulence genes such as astA, cnf1, eaeA, cnf2 and bfpA genes were detected in 14 (47%), 11 (37%), four (13%), three (10%) and one (3.3%) strains of CTEC, respectively. However, the other common virulence‐associated genes specific for DEC were not detected in these strains. Interestingly, an untypable cdt gene was detected by PCR‐RFLP in Providencia alcalifaciens. Our data indicate that CTEC may be associated with diarrheal children in Japan and most of them do not belong to a conventional enteropathogenic pathovar and thus differ from strains isolated in developing countries.
Clinical trial: a randomized, study comparing meperidine (pethidine) and fentanyl in adult gastrointestinal endoscopy
Authors: ROBERTSON D. J. , JACOBS D. P. , MACKENZIE T. A. , ORINGER J. A. , ROTHSTEIN R. I.
Published: January 2009

Background  There is little evidence to guide choice between meperidine (pethidine) and fentanyl for sedation for gastrointestinal endoscopy.

Aim  To compare meperidine with fentanyl in terms of procedure time and analgesia.

Methods  Single centre randomized controlled trial. Patients received narcotic doses and midazolam at the discretion of the attending endoscopist who was unaware of narcotic assignment. Endoscopy and recovery times were then recorded. The main outcome was total procedure time, defined as endoscopy time plus recovery time. Patient discomfort was assessed prior to discharge via visual analogue scale (VAS).

Results  In total, 55 patients were randomized to meperidine [44 colonoscopy and 11 esophagogastroduodenoscopy (EGD)] and 56 to fentanyl (45 colonoscopy and 11 EGD). Total procedure time was shorter for those receiving fentanyl (mean = 87.7 min) than for those receiving meperidine (mean = 102.9 min) (P = 0.05). The difference between the groups was explained by a shorter mean recovery time in the fentanyl group (63.0 min) than in the meperidine group (76.2 min) (P = 0.07). Based on post procedure pain scores, examinations with meperidine (mean = 1.99) were less painful when compared with those receiving fentanyl (mean = 2.86, P = 0.03).

Conclusions  Fentanyl shortened total procedure time by reducing recovery time. A simple change in narcotic choice could increase endoscopy unit efficiency.
Predictors of corticosteroid‐dependent and corticosteroid‐refractory inflammatory bowel disease: analysis of a Chinese cohort study
Authors: CHOW D. K. L. , SUNG J. J. Y. , TSOI K. K. F. , WONG V. W. S. , WU J. C. Y. , LEONG R. W. L. , CHAN F. K. L.
Published: January 2009

Background  Patients with inflammatory bowel disease (IBD) who are corticosteroid‐dependent or ‐refractory are at higher risk of developing disease‐ and treatment‐related complications.

Aims  To identify retrospectively clinical factors present at diagnosis that predict the occurrence of corticosteroid dependency and refractoriness in Crohn’s disease (CD) and ulcerative colitis (UC) patients.

Methods  A total of 310 IBD patients (134 CD, 176 UC) were observed for 2140 person years and their use of systemic corticosteroids was determined. Outcomes of corticosteroid dependency and refractoriness were recorded. Univariate and multivariate analyses were performed to determine the clinical factors associated with outcomes.

Results  Seventy‐seven (57.5%) CD and 95 (54.0%) UC patients had received corticosteroids during study period. In CD, thrombocytosis [Hazard ratio (HR):3.0] predicted, whereas colonic CD (HR:0.3) negatively predicted corticosteroid dependency. Stricturing phenotype (HR:4.5) predicted corticosteroid‐refractory CD. For UC, thrombocytosis (HR:3.9) and extensive colitis (HR:1.7) predicted corticosteroid dependency. Presence of anaemia (HR:10.8) at diagnosis and initial requirement of total parenteral nutrition (TPN) (HR:18.8) predicted corticosteroid‐refractory UC. The cumulative risks of surgery were 17.8% and 5.4% for CD and UC patients respectively at 1 year after starting corticosteroids.

Conclusions  Thrombocytosis at diagnosis predicted corticosteroid‐dependency in IBD. Stricturing phenotype of CD and the presence of anaemia in UC predicted subsequent course of corticosteroid refractoriness.