bluuebunny/crossref_metadata_2025 huggingface dataset:
Complex genetic, photothermal, and photoacoustic analysis of nanoparticle-plant interactions
Authors: Khodakovskaya Mariya V. , de Silva Kanishka , Nedosekin Dmitry A. , Dervishi Enkeleda , Biris Alexandru S. , Shashkov Evgeny V. , Galanzha Ekaterina I. , Zharov Vladimir P.
Published: December 2010

Understanding the nature of interactions between engineered nanomaterials and plants is crucial in comprehending the impact of nanotechnology on the environment and agriculture with a focus on toxicity concerns, plant disease treatment, and genetic engineering. To date, little progress has been made in studying nanoparticle-plant interactions at single nanoparticle and genetic levels. Here, we introduce an advanced platform integrating genetic, Raman, photothermal, and photoacoustic methods. Using this approach, we discovered that multiwall carbon nanotubes induce previously unknown changes in gene expression in tomato leaves and roots, particularly, up-regulation of the stress-related genes, including those induced by pathogens and the water-channelLeAqp2gene. A nano-bubble amplified photothermal/photoacoustic imaging, spectroscopy, and burning technique demonstrated the detection of multiwall carbon nanotubes in roots, leaves, and fruits down to the single nanoparticle and cell level. Thus, our integrated platform allows the study of nanoparticles’ impact on plants with higher sensitivity and specificity, compared to existing assays.
Immature T-cell clustering and efficient differentiation require the polarity protein Scribble
Authors: Pike Kelly A. , Kulkarni Sarang , Pawson Tony
Published: December 2010

T-cell polarization is required for cell migration and cell–cell interactions, cellular behaviors crucial for lymphocyte differentiation. Despite expression of the epithelial polarity network in T cells, neither its contribution to thymocyte polarity nor its requirement during development is known. We report here that depletion of the polarity protein Scribble in hematopoietic progenitor cells results in inefficient T-cell development characterized by a partial developmental block during the early double-negative (DN) stage of differentiation. Scribble-depleted hematopoietic progenitor cells exhibit a delayed transition into late CD44
lo/−
CD25
+
DN3 cells, evidenced by the accumulation of early CD44
int
CD25
+
DN3 cells. As a consequence, a limited cellular expansion and a reduced frequency of intracellular T-cell receptor β–positive DN3 cells are observed among Scribble-deficient differentiating T cells. Moreover, whereas purified Scribble-depleted DN2 and DN3 cells do not exhibit compromised spontaneous motility, T-cell clustering and prolonged homotypic interactions among such cells are reduced. This deficiency correlates with a lack of polarization of the integrin LFA-1 during T-cell migration or on the initiation of T-cell–T-cell interactions. Scribble is therefore a critical contributor to the clustering of immature T cells, an event shown here to be necessary for efficient developmental progression.
Applying cognitive linguistics to instructed L2 learning
Authors: Tyler Andrea , Mueller Charles M. , Ho Vu
Published: December 2010

This paper reports the results of a quasi-experimental effects-of-instruction study examining the efficacy of applying a Cognitive Linguistic (CL) approach to L2 learning of the semantics of English modals. In spite of their frequency in typical input, modal verbs present L2 learners with difficulties, party due to their inherent complexity — modals typically have two divergent senses — a root1 sense and an epistemic sense. ELT textbooks and most grammar books aimed at L2 teachers present the two meanings as homophones, failing to address any systematic semantic patterning in the modal system as a whole. Additionally, ELT texts tend to present modals from a speech act perspective. In contrast, CL analyses (e. g., Langacker 1991; Nuyts 2001; Sweetser 1990; Talmy 1988) offer both a systematic, motivated representation of the relationship between the root and epistemic meanings and a rather precise representation of the semantics of each modal. To test the pedagogical effectiveness of a CL account of modals, an effects-of-instruction study was conducted with three groups of adult, high-intermediate ESL learners: a Cognitive treatment group, a Speech Acts2 treatment group, and a Control group. Results of an ANCOVA indicated that the Cognitive treatment group demonstrated significantly more improvement than the Speech Acts treatment group. The experiment thus lends empirical support for the position that CL, in addition to offering a compelling analytical account of language, may also provide the basis for more effective grammar instruction than that found in most current ELT teaching materials.
Metonymic inferencing and second language acquisition
Authors: Barcelona Antonio
Published: December 2010

The article is a reflection on the various areas of cognitive linguistic research on metonymy that are of potential relevance for SLA. Three of them are particularly relevant: (1) research on metonymy-guided inferencing; (2) research on metonymy-based lexical polysemy, and (3) research on metonymy-based grammatical constructions. Of the three main areas with which the paper is mainly concerned, area (1) is particularly relevant for research on second language comprehension, especially in utterance and discourse types heavily relying on the inferential work of the comprehender; area (2) has already proved to be very useful for research on the inferencing strategies followed by second language learners in their comprehension of new lexical senses in context; and area (3) should be helpful for research on the acquisition of grammatical constructions by these learners.
Metaphorical competence in EFL
Authors: MacArthur Fiona
Published: December 2010

Although there exists a number of studies that have shown the benefits of applying the cognitive linguistics notion of motivation to foster comprehension and retention of conventional English metaphors, relatively little attention has been paid to EFL learners’ productive use of metaphor in speech and writing. Using data gathered in a post-intermediate English language classroom, I describe and explore the metaphorical language used by undergraduate students in their writing. The data show that learners use metaphor to express their ideas on complex, abstract topics, but that the resulting metaphorical usage is not always conventional or felicitous. Since metaphor is deployed by EFL learners in response to particular communication demands, teachers need to find ways of providing appropriate feedback on learners’ efforts to make use of their limited linguistic resources to express their own meanings. However, how effective feedback is to be given is not always straightforward. I discuss some of the problems involved and suggest areas that are in need of further research.
Narrating traumas and transgressions
Authors: Mansfield Cade D. , Mclean Kate C. , Lilgendahl Jennifer P.
Published: December 2010

Experiencing personal growth via reflection on negative events is well established. Yet, we know less about how people process and grow (or not) from different types of negative events, and how such narrative processing might differentially predict important outcomes, in this case, wisdom and well-being. Eighty-five community members participated in an online study examining the narrative processing and self-perceptions of traumas and transgressions, and how narrative processing predicted wisdom and well-being. Results showed few differences in the processing of traumas and transgressions, though the latter was viewed as less important to the self compared to the former. Further, growth in transgressions predicted wisdom, and narrative resolution of transgressions predicted well-being. In contrast, for trauma narratives well-being was predicted by the interaction of resolution and narrative complexity. Discussion focuses on the role of event types in narrative processing in relation to wisdom and well-being.
Big stories co-constructed
Authors: Helsig Sarah
Published: December 2010

Tying up to previous narrative work that is concerned with the interrelations between big story and small story research (Bamberg, 2006; Freeman, 2006; Georgakopoulou, 2006b), this article aims to demonstrate that big story research can profit from methodological procedures that understand narrative research interviews as interactional encounters and positions assigned to the narrator during this encounter as impinging on the biographic accounts they deliver. For that purpose, I take the interaction between the interviewer and the interviewee — both before and during the actual interview — as an analytical point of departure and argue that the self-constructions that narrators undertake when engaging in (auto)biographic self-reflection have to and can only be understood against the background of this embedding interaction.
Tales of the bitter and sweet
Authors: Sandel Todd L.
Published: December 2010

Recent research in Taiwanese families has found that children’s transgressions are narratable and parents encourage children to confess and reflect upon their faults. Little, however, is known if adults do the same when talking with children or other adults. This study examines transgression stories from interviews with 102 adult participants in Taiwan. It finds adults often tell stories about the faults of close family members such as spouses, parents, children, and aunts and uncles. However, they are less likely to tell stories of their own faults. Furthermore, they say telling transgression stories to children must take into account the child’s age and the story’s potential didactic value. The study also finds that many stories, especially those told by older adults, i.e., grandparents, articulate part of a “master story” lamenting how they persevered from a bitter past to a much better present. Such a story shapes cross-generational narrative and lends greater moral authority to elders. Finally, implications are discussed how this study sheds light on a theory of confessional narratives by authority figures across different cultures.
Mouse intact cardiac myocyte mechanics: cross-bridge and titin-based stress in unactivated cells
Authors: King Nicholas M.P. , Methawasin Methajit , Nedrud Joshua , Harrell Nicholas , Chung Charles S. , Helmes Michiel , Granzier Henk
Published: December 2010

A carbon fiber–based cell attachment and force measurement system was used to measure the diastolic stress–sarcomere length (SL) relation of mouse intact cardiomyocytes, before and after the addition of actomyosin inhibitors (2,3-butanedione monoxime [BDM] or blebbistatin). Stress was measured during the diastolic interval of twitching myocytes that were stretched at 100% base length/second. Diastolic stress increased close to linear from 0 at SL 1.85 µm to 4.2 mN/mm2 at SL 2.1 µm. The actomyosin inhibitors BDM and blebbistatin significantly lowered diastolic stress by ∼1.5 mN/mm2 (at SL 2.1 µm, ∼30% of total), suggesting that during diastole actomyosin interaction is not fully switched off. To test this further, calcium sensitivity of skinned myocytes was studied under conditions that simulate diastole: 37°C, presence of Dextran T500 to compress the myofilament lattice to the physiological level, and [Ca2+] from below to above 100 nM. Mean active stress was significantly increased at [Ca2+] > 55 nM (pCa 7.25) and was ∼0.7 mN/mm2 at 100 nM [Ca2+] (pCa 7.0) and ∼1.3 mN/mm2 at 175 nM Ca2+ (pCa 6.75). Inhibiting active stress in intact cells attached to carbon fibers at their resting SL and stretching the cells while first measuring restoring stress (pushing outward) and then passive stress (pulling inward) made it possible to determine the passive cell’s mechanical slack SL as ∼1.95 µm and the restoring stiffness and passive stiffness of the cells around the slack SL each as ∼17 mN/mm2/µm/SL. Comparison between the results of intact and skinned cells shows that titin is the main contributor to restoring stress and passive stress of intact cells, but that under physiological conditions, calcium sensitivity is sufficiently high for actomyosin interaction to contribute to diastolic stress. These findings are relevant for understanding diastolic function and for future studies of diastolic heart failure.
Nilpotency of normal subgroups having two 𝐺-class sizes
Authors: Alemany Elena , Beltrán Antonio , Felipe María
Published: December 2010

Let

G
G

be a finite group. If

N
N

is a normal subgroup which has exactly two

G
G

-conjugacy class sizes, then

N
N

is nilpotent. In particular, we show that

N
N

is abelian or is the product of a

p
p

-group

P
P

by a central subgroup of

G
G

. Furthermore, when

P
P

is not abelian,

P

/

(

Z

(
G
)
∩
P
)

P/(\textbf {Z}(G)\cap P)

has exponent

p
p

.
Harmonic cohomology of symplectic fiber bundles
Authors: Ebner Oliver , Haller Stefan
Published: December 2010

We show that every de Rham cohomology class on the total space of a symplectic fiber bundle with closed Lefschetz fibers admits a Poisson harmonic representative in the sense of Brylinski. The proof is based on a new characterization of closed Lefschetz manifolds.
Buser’s isoperimetric inequalities with integral norms of Ricci curvature
Authors: Paeng Seong-Hun
Published: December 2010

We generalize Buser’s isoperimetric inequality with integral norms of Ricci curvature.
Positive entropy homeomorphisms of chainable continua and indecomposable subcontinua
Authors: Mouron Christopher
Published: December 2010

It is shown that if

X
X

is a chainable continuum and

h
:
X
⟶
X

h:X\longrightarrow X

is a homeomorphism such that the topological entropy of

h
h

is greater than 0, then

X
X

must contain an indecomposable subcontinuum. This answers a question of Barge.
On quasiconformal maps with identity boundary values
Authors: Manojlović V. , Vuorinen M.
Published: December 2010

Quasiconformal homeomorphisms of the unit ball

B
n

B^n

of

R

n

,
n
≥
3
,

{\mathbb R}^n, n \ge 3,

onto itself with identity boundary values are studied. A spatial analogue of Teichmüller’s theorem is proved.
A Colding-Minicozzi stability inequality and its applications
Authors: Espinar José , Rosenberg Harold
Published: December 2010

We consider operators

L
L

acting on functions on a Riemannian surface,

Σ
\Sigma

, of the form
\[

L
=
Δ
+
V
−
a
K
.

L=\Delta +V-a K .

\]

Here

Δ
\Delta

is the Laplacian of

Σ
\Sigma

,

V
V

a nonnegative potential on

Σ
\Sigma

,

K
K

the Gaussian curvature and

a
a

is a nonnegative constant.

Such operators

L
L

arise as the stability operator of

Σ
\Sigma

immersed in a Riemannian

3
−

3-

manifold with constant mean curvature (for particular choices of

V
V

and

a
a

). We assume that

L
L

is nonpositive acting on functions compactly supported on

Σ
\Sigma

and we obtain results in the spirit of some theorems of Fischer-Colbrie-Schoen, Colding-Minicozzi and Castillon. We extend these theorems to

a
≤
1

/

4

a \leq 1/4

. We obtain results on the conformal type of

Σ
\Sigma

and a distance (to the boundary) lemma.
On the Dirichlet problem for first order quasilinear equations on a manifold
Authors: Panov E.
Published: December 2010

We study the Dirichlet problem for a first order quasilinear equation on a smooth manifold with boundary. The existence and uniqueness of a generalized entropy solution are established. The uniqueness is proved under some additional requirement on the field of coefficients. It is shown that generally the uniqueness fails. The nonuniqueness occurs because of the presence of the characteristics not outgoing from the boundary (including closed ones). The existence is proved in a general case. Moreover, we establish that among generalized entropy solutions laying in the ball‖u‖∞≤R\|u\|_\infty \le Rthere exist unique maximal and minimal solutions. To prove our results, we use the kinetic formulation similar to the one by C. Imbert and J. Vovelle.
Forcing relation on patterns of invariant sets and reductions of interval maps
Authors: Mai Jie-Hua , Shao Song
Published: December 2010

Patterns of invariant sets of interval maps are the equivalence classes of invariant sets under order-preserving conjugacy. In this paper we study forcing relations on patterns of invariant sets and reductions of interval maps. We show that for any interval mapffand any nonempty invariant setSSofffthere exists a reductionggofffsuch thatg|S=f|Sg|_S=f|_Sandggis a monotonic extension off|Sf|_S. By means of reductions of interval maps, we obtain some general results about forcing relations between the patterns of invariant sets of interval maps, which extend known results about forcing relations between patterns of periodic orbits. We also give sufficient conditions for a general pattern to force a given minimal pattern in the sense of Bobok. Moreover, as applications, we give a new and simple proof of the converse of the Sharkovskiĭ Theorem and study fissions of periodic orbits, entropies of patterns, etc.
Stein spaces characterized by their endomorphisms
Authors: Andrist Rafael
Published: December 2010

Finite-dimensional Stein spaces admitting a proper holomorphic embedding of the complex line are characterized, among all complex spaces, by their holomorphic endomorphism semigroup in the sense that any semigroup isomorphism induces either a biholomorphic or an antibiholomorphic map between them.
1-point Gromov-Witten invariants of the moduli spaces of sheaves over the projective plane
Authors: Li Wei-Ping , Qin Zhenbo
Published: December 2010

The Gieseker-Uhlenbeck morphism maps the Gieseker moduli space of stable rank-

2
2

sheaves on a smooth projective surface to the Uhlenbeck compactification and is a generalization of the Hilbert-Chow morphism for Hilbert schemes of points. When the surface is the complex projective plane, we determine all the

1
1

-point genus-

0
0

Gromov-Witten invariants extremal with respect to the Gieseker-Uhlenbeck morphism. The main idea is to understand the virtual fundamental class of the moduli space of stable maps by studying the obstruction sheaf and using a meromorphic

2
2

-form on the Gieseker moduli space.
Representations of logmodular algebras
Authors: Paulsen Vern , Raghupathi Mrinal
Published: December 2010

We study the question of whether or not contractive representations of logmodular algebras are completely contractive. We prove that a 2-contractive representation of a logmodular algebra extends to a positive map on the enveloping

C
∗

C^*

-algebra, which we show generalizes a result of Foias and Suciu on uniform logmodular algebras. Our proof uses non-commutative operator space generalizations of classical results on 2-summing maps and semi-spectral measures. We establish some matrix factorization results for uniform logmodular algebras.
Generalised morphisms of 𝑘-graphs: 𝑘-morphs
Authors: Kumjian Alex , Pask David , Sims Aidan
Published: December 2010

In a number of recent papers,(k+l)(k+l)-graphs have been constructed fromkk-graphs by inserting new edges in the lastlldimensions. These constructions have been motivated byC∗C^*-algebraic considerations, so they have not been treated systematically at the level of higher-rank graphs themselves. Here we introducekk-morphs, which provide a systematic unifying framework for these various constructions. We think ofkk-morphs as the analogue, at the level ofkk-graphs, ofC∗C^*-correspondences betweenC∗C^*-algebras. To make this analogy explicit, we introduce a category whose objects arekk-graphs and whose morphisms are isomorphism classes ofkk-morphs. We show how to extend the assignmentΛ↦C∗(Λ)\Lambda \mapsto C^*(\Lambda )to a functor from this category to the category whose objects areC∗C^*-algebras and whose morphisms are isomorphism classes ofC∗C^*-correspondences.
Least action principle and the incompressible Euler equations with variable density
Authors: Lopes Filho Milton , Nussenzveig Lopes Helena , Precioso Juliana
Published: December 2010

In this article we study a variational formulation, proposed by V. I. Arnold and by Y. Brenier, for the incompressible Euler equations with variable density. We consider the problem of minimizing an action functional, the integral in time of the kinetic energy, among fluid motions considered as trajectories in the group of volume-preserving diffeomorphisms beginning at the identity and ending at some fixed diffeomorphism at a given time. We show that a relaxed version of this variational problem always has a solution, and we derive an Euler-Lagrange system for the relaxed minimization problem which we call the relaxed Euler equations. Finally, we prove consistency between the relaxed Euler equations and the classical Euler system, showing that weak solutions of the relaxed Euler equations with the appropriate geometric structure give rise to classical Euler solutions and that classical solutions of the Euler system induce weak solutions of the relaxed Euler equations. The first consistency result is new even in the constant density case. The remainder of our analysis is an extension of the work of Y. Brenier (1999) to the variable density case.
Geometrically finite and semi-rational branched coverings of the two-sphere
Authors: Cui Guizhen , Jiang Yunping
Published: December 2010

In 1982, Thurston gave a necessary and sufficient condition for a critically finite branched covering of the two-sphere to itself to be combinatorially equivalent to a rational map. We discuss extending this result to geometrically finite rational maps. We give an example to show that Thurston’s original condition is not sufficient. This example is topologically pathological near accumulation points of the postcritical set. We give two conditions forbidding such pathology, show that they are equivalent, and (in a sequel to the present paper) will show that Thurston’s condition together with this tameness is both necessary and sufficient to characterize geometrically finite rational maps.
Patching subfields of division algebras
Authors: Harbater David , Hartmann Julia , Krashen Daniel
Published: December 2010

Given a field

F
F

, one may ask which finite groups are Galois groups of field extensions

E

/

F

E/F

such that

E
E

is a maximal subfield of a division algebra with center

F
F

. This question was originally posed by Schacher, who gave partial results in the case

F
=

Q

F = \mathbb Q

. Using patching, we give a complete characterization of such groups in the case that

F
F

is the function field of a curve over a complete discretely valued field with algebraically closed residue field of characteristic zero, as well as results in related cases.
Averages over hyperplanes, sum-product theory in vector spaces over finite fields and the Erdős-Falconer distance conjecture
Authors: Hart Derrick , Iosevich Alex , Koh Doowon , Rudnev Misha
Published: December 2010

We prove a pointwise and average bound for the number of incidences between points and hyperplanes in vector spaces over finite fields. While our estimates are, in general, sharp, we observe an improvement for product sets and sets contained in a sphere. We use these incidence bounds to obtain significant improvements on the arithmetic problem of covering

F

q

{\mathbb F}_q

, the finite field with

q
q

elements, by

A
⋅
A
+
⋯
+
A
⋅
A

A \cdot A+\dots +A \cdot A

, where

A
A

is a subset

F

q

{\mathbb F}_q

of sufficiently large size. We also use the incidence machinery and develop arithmetic constructions to study the Erdős-Falconer distance conjecture in vector spaces over finite fields. We prove that the natural analog of the Euclidean Erdős-Falconer distance conjecture does not hold in this setting. On the positive side, we obtain good exponents for the Erdős-Falconer distance problem for subsets of the unit sphere in

F

q
d

\mathbb F_q^d

and discuss their sharpness. This results in a reasonably complete description of the Erdős-Falconer distance problem in higher-dimensional vector spaces over general finite fields.
Cluster algebras and semipositive symmetrizable matrices
Authors: Seven Ahmet
Published: December 2010

There is a particular analogy between combinatorial aspects of cluster algebras and Kac-Moody algebras: roughly speaking, cluster algebras are associated with skew-symmetrizable matrices while Kac-Moody algebras correspond to (symmetrizable) generalized Cartan matrices. Both classes of algebras and the associated matrices have the same classification of finite type objects by the well-known Cartan-Killing types. In this paper, we study an extension of this correspondence to the affine type. In particular, we establish the cluster algebras which are determined by the generalized Cartan matrices of affine type.
Lattès-type mappings on compact manifolds
Authors: Astola Laura , Kangaslampi Riikka , Peltonen Kirsi
Published: December 2010

A uniformly quasiregular mapping acting on a compact Riemannian manifold distorts the metric by a bounded amount, independently of the number of iterates. Such maps are rational with respect to some measurable conformal structure and there is a Fatou-Julia type theory associated with the dynamical system obtained by iterating these mappings. We study a rich subclass of uniformly quasiregular mappings that can be produced using an analogy of classical Lattès’ construction of chaotic rational functions acting on the extended planeC¯\bar {\mathbb {C}}. We show that there is a plenitude of compact manifolds that support these mappings. Moreover, we find that in some cases there are alternative ways to construct this type of mapping with different Julia sets.
Changes between consecutive broods in the fecundity of the spider crab, Maja brachydactyla
Authors: Verísimo Patricia , Bernárdez Cristina , González-Gurriarán Eduardo , Freire Juan , Muiño Ramón , Fernández Luis
Published: December 2010

Verísimo, P., Bernárdez, C., González-Gurriarán, E., Freire, J., Muiño, R., and Fernández, L. 2011. Changes between consecutive broods in the fecundity of the spider crab, Maja brachydactyla. – ICES Journal of Marine Science, 68: . An analysis of the fecundity of Maja brachydactyla and the possible causes for its variability was carried out during two breeding cycles in the Ría de Arousa (Galicia, NW Spain). Based on brood samples with known weight data, subsample counts were taken of the number of eggs (125 081–530 309 eggs), and dry weight and volume of individual eggs were recorded. The main cause of variability in egg number and dry weight of the broods was female body length. Moreover, the size of the broods during the two breeding cycles and of subsequent broods exhibited significant differences in terms of both fecundity (p < 0.05) and brood dry weight (p< 0.05). The first broods contained fewer, larger eggs (a greater energy investment per egg), whereas subsequent broods contained more, smaller eggs (less energy investment per egg).
Real-time calibration of in situ measurements of target strength
Authors: MacLennan David N.
Published: December 2010

MacLennan, D. N. 2011. Real-time calibration of in situ measurements of target strength. – ICES Journal of Marine Science, 68: . The in situ measurement of target strength (TS) depends on exactly one fish being within the sampled volume. This is more likely to occur the nearer the transducer is to the fish targets. The detection rate can be improved by lowering the transducer on a cable from a stationary vessel, so decreasing the range to the observed fish. In this application, a standard sphere is commonly suspended below the transducer to provide the real-time calibration of the received signals. However, forward scattering by the sphere distorts the transmitted pulse, and equally the returning fish echoes, causing a bias in the estimated TS. Further, for a split-beam transducer, forward-scattering of the fish echo by the sphere modifies the phase differences observed between the transducer segments. This changes the apparent distribution of targets, but not the estimated TS. The biases are not large, those considered being within ±0.9 dB, and they depend on the sonar frequency, the target range, and the direction. The theory of these effects is examined, and formulae are provided for correcting the observed fish echo to that which would be received in free-field conditions, i.e. with the sphere removed.
Fisheries bycatch data provide insights into the distribution of the mauve stinger (Pelagia noctiluca) around Ireland
Authors: Bastian Thomas , Stokes David , Kelleher Jane E. , Hays Graeme C. , Davenport John , Doyle Thomas K.
Published: December 2010

Bastian, T., Stokes, D., Kelleher, J. E., Hays, G. C., Davenport, J., and Doyle, T. K. 2011. Fisheries bycatch data provide insights into the distribution of the mauve stinger (Pelagia noctiluca) around Ireland. – ICES Journal of Marine Science, 68: . There is concern that jellyfish populations are proliferating in the Northeast Atlantic and that their socio-economic impacts will increase. Using information from the Irish Groundfish Survey, data are presented on the distribution of the mauve stinger, Pelagia noctiluca, over an area >160 000 km² around Ireland and the UK in 2009. The species accounted for 93% of the overall catch of gelatinous organisms, with an average catch biomass of 0.26 ± 2.3 kg ha−1. The study area was divided into four subregions (North, West, Southwest, and South), and the distribution and abundance of P. noctiluca displayed both inter- and intraregional variations. Individual bell diameters ranged from 1 to 13.5 cm (median 4.5 cm, s.d. 1.2 cm), and the size distribution also varied spatially. It is the first time that such detailed information has been made available for P. noctiluca in a part of the Northeast Atlantic where its impact on the salmon aquaculture industry can be considerable. Finally, the possibility of using annual datasets from this type of fisheries survey to develop time-series that, in the future, will allow investigation of relationships between long-term variations of P. noctiluca populations and climatic factors in the area is addressed.
Regional-scale changes in diatom distribution in the Humboldt upwelling system as revealed by remote sensing: implications for fisheries
Authors: Jackson Thomas , Bouman Heather A. , Sathyendranath Shubha , Devred Emmanuel
Published: December 2010

Jackson, T., Bouman, H. A., Sathyendranath, S., and Devred, E. 2011. Regional-scale changes in diatom distribution in the Humboldt upwelling system as revealed by remote sensing: implications for fisheries. – ICES Journal of Marine Science, 68: 729–736. A diatom-detection algorithm was parametrized for the Humboldt upwelling system using local cruise data that were first validated, then used to create monthly composites of diatom distribution from 0 to 40°S and 90 to 70°W for both normal and El Niño conditions. There was a 50% reduction in the areal extent of diatom-dominated waters during the peak of the 1997 El Niño. The extent of the coastward contraction in the diatom-dominated area varied along the South American coastline. These regional shifts in phyto- and zooplankton communities would have increased food stress on local anchovy (Engraulis ringens) populations and could have contributed to diminished larval survival and landings the following year. A region of strong upwelling over the wide Peruvian continental shelf around 15°S was the only area that maintained a strong diatom population throughout the El Niño; the area may require special protection from fishing pressure in years following an El Niño event.
Ecotypes as a concept for exploring responses to climate change in fish assemblages
Authors: Engelhard Georg H. , Ellis Jim R. , Payne Mark R. , ter Hofstede Remment , Pinnegar John K.
Published: December 2010

Engelhard, G. H., Ellis, J. R., Payne, M. R., ter Hofstede, R., and Pinnegar, J. K. 2011. Ecotypes as a concept for exploring responses to climate change in fish assemblages. – ICES Journal of Marine Science, 68: . How do species-rich fish assemblages respond to climate change or to other anthropogenic or environmental drivers? To explore this, a categorization concept is presented whereby species are assigned with respect to six ecotype classifications, according to biogeography, horizontal and vertical habitat preference, trophic guild, trophic level, or body size. These classification schemes are termed ecotypology, and the system is applied to fish in the North Sea using International Bottom Trawl Survey data. Over the period 1977–2008, there were changes in the North Sea fish community that can be related to fish ecotypes. Broadly speaking, there were steady increases in abundance of species that were either Lusitanian, small-bodied, or low-/mid-trophic-level ecotypes, and generally declining or only marginally increasing trends of most Boreal, large-bodied, or high-trophic-level ecotypes or combinations of them. The post-1989 warm biological regime appears to have favoured pelagic species more than demersal species. These community-level patterns agree with the expected responses of ecotypes to climate change and also with anticipated vulnerability to fishing pressure.
Gelatinization, Pasting, and Gelling Properties of Sweetpotato and Wheat Starch Blends
Authors: Zhu Fan , Corke Harold
Published: December 2010

Sweetpotato starch is high yielding but has very limited uses. It is possible to expand its application by blending it with other starches to obtain novel properties. In this study, functional properties of the blends of native sweetpotato starch with native, acid‐thinned, and hydroxypropylated wheat starch were studied at different ratios (75:25, 50:50, 25:75). The swelling factor, extent of amylose leaching, pasting, and gel textural properties of the blends were nonadditive of their individual components, and could be mathematically modeled by quadratic equations in relation to the ratios. Two peaks during pasting were observed for some starch mixtures studied by Rapid ViscoAnalyser (RVA). The gelatinization and retrogradation enthalpies (ΔH) of the blends were additive of their individual components and could be modeled by linear equations. All starch mixtures exhibited two peaks during differential scanning calorimetry (DSC) scan for gelatinization, but a single peak for retrograded starches. This study may provide basis for formulation of mixtures using starch from diverse sources to develop more natural starch systems with a range of physicochemical properties.
Quantitative Proteomic Analysis of the Interaction Between the Endophytic Plant-Growth-Promoting Bacterium Gluconacetobacter diazotrophicus and Sugarcane
Authors: Lery Letícia M. S. , Hemerly Adriana S. , Nogueira Eduardo M. , von Krüger Wanda M. A. , Bisch Paulo M.
Published: December 2010

Gluconacetobacter diazotrophicus is a plant-growth-promoting bacterium that colonizes sugarcane. In order to investigate molecular aspects of the G. diazotrophicus–sugarcane interaction, we performed a quantitative mass spectrometry-based proteomic analysis by 15N metabolic labeling of bacteria, root samples, and co-cultures. Overall, more than 400 proteins were analyzed and 78 were differentially expressed between the plant–bacterium interaction model and control cultures. A comparative analysis of the G. diazotrophicus in interaction with two distinct genotypes of sugarcane, SP70-1143 and Chunee, revealed proteins with fundamental roles in cellular recognition. G. diazotrophicus presented proteins involved in adaptation to atypical conditions and signaling systems during the interaction with both genotypes. However, SP70-1143 and Chunee, sugarcane genotypes with high and low contribution of biological nitrogen fixation, showed divergent responses in contact with G. diazotrophicus. The SP70-1143 genotype overexpressed proteins from signaling cascades and one from a lipid metabolism pathway, whereas Chunee differentially synthesized proteins involved in chromatin remodeling and protein degradation pathways. In addition, we have identified 30 bacterial proteins in the roots of the plant samples; from those, nine were specifically induced by plant signals. This is the first quantitative proteomic analysis of a bacterium–plant interaction, which generated insights into early signaling of the G. diazotrophicus–sugarcane interaction.
Development of a Host-Induced RNAi System in the Wheat Stripe Rust Fungus Puccinia striiformis f. sp. tritici
Authors: Yin Chuntao , Jurgenson James E. , Hulbert Scot H.
Published: December 2010

Rust fungi cause devastating diseases of wheat and other cereal species globally. Genetic resistance is the preferred method to control rusts but the effectiveness of race-specific resistance is typically transient due to the genetic plasticity of rust populations. The advent of RNA interference (RNAi) technology has shown promise for the engineering of resistance to some biotrophic pathogens in plants by altering the expression of essential pathogens' genes. Gene fragments from the rust fungi Puccinia striiformis f. sp. tritici or P. graminis f. sp. tritici were delivered to plant cells through the Barley stripe mosaic virus system, and some reduced the expression of the corresponding genes in the rust fungus. The ability to detect suppression was associated with the expression patterns of the fungal genes because reduction was only detected in transcripts with relatively high levels of expression in fungal haustoria. The results indicate that an in planta RNAi approach can be used in functional genomics research for rust fungi and that it could potentially be used to engineer durable resistance.
Effects of Integrating Cultivar Resistance and Fungicide Application on Fusarium Head Blight and Deoxynivalenol in Winter Wheat
Authors: Wegulo Stephen N. , Bockus William W. , Nopsa John Hernandez , De Wolf Erick D. , Eskridge Kent M. , Peiris Kamaranga H. S. , Dowell Floyd E.
Published: December 2010

Fusarium head blight (FHB) or scab, incited by Fusarium graminearum, can cause significant economic losses in small grain production. Five field experiments were conducted from 2007 to 2009 to determine the effects on FHB and the associated mycotoxin deoxynivalenol (DON) of integrating winter wheat cultivar resistance and fungicide application. Other variables measured were yield and the percentage of Fusarium-damaged kernels (FDK). The fungicides prothioconazole + tebuconazole (formulated as Prosaro 421 SC) were applied at the rate of 0.475 liters/ha, or not applied, to three cultivars (experiments 1 to 3) or six cultivars (experiments 4 and 5) differing in their levels of resistance to FHB and DON accumulation. The effect of cultivar on FHB index was highly significant (P < 0.0001) in all five experiments. Under the highest FHB intensity and no fungicide application, the moderately resistant cultivars Harry, Heyne, Roane, and Truman had less severe FHB than the susceptible cultivars 2137, Jagalene, Overley, and Tomahawk (indices of 30 to 46% and 78 to 99%, respectively). Percent fungicide efficacy in reducing index and DON was greater in moderately resistant than in susceptible cultivars. Yield was negatively correlated with index, with FDK, and with DON, whereas index was positively correlated with FDK and with DON, and FDK and DON were positively correlated. Correlation between index and DON, index and FDK, and FDK and DON was stronger in susceptible than in moderately resistant cultivars, whereas the negative correlation between yield and FDK and yield and DON was stronger in moderately resistant than in susceptible cultivars. Overall, the strongest correlation was between index and DON (0.74 ≤ R ≤ 0.88, P ≤ 0.05). The results from this study indicate that fungicide efficacy in reducing FHB and DON was greater in moderately resistant cultivars than in susceptible ones. This shows that integrating cultivar resistance with fungicide application can be an effective strategy for management of FHB and DON in winter wheat.
Evaluation of Microbial Products for Management of Powdery Mildew on Summer Squash and Cantaloupe in Florida
Authors: Zhang Shouan , Vallad Gary E. , White Thomas L. , Huang Cheng-Hua
Published: December 2010

Powdery mildew, caused by Podosphaera xanthii (syn. Sphaerotheca fuliginea auct. p.p.), is a serious and frequently occurring disease of cucurbits worldwide. Efficacy of four microbial products (i.e., Actinovate AG, Companion, BU EXP 1216C, and BU EXP 1216S), which contain microbes as the active ingredient, were evaluated on summer squash and cantaloupe against powdery mildew when applied alone or in alternation with a half-rate of conventional fungicide under greenhouse and field conditions. In greenhouse experiments, the product BU EXP 1216S significantly (P < 0.05) reduced the disease severity by nearly 70% relative to the water control. The level of control achieved was not significantly different from that obtained with Procure 480SC (triflumizole), the half-rate of conventional fungicide treatment, in two of four greenhouse experiments. Compared with the untreated water control, BU EXP 1216C and BU EXP 1216S, when applied alternately with Procure 480SC, consistently promoted plant growth measured by plant height, stem caliper, total fresh weight, and chlorophyll content in the leaves. The degree of increase was 11.6 and 11.3% in plant height, 15.6 and 19.8% in stem caliper, 25 and 40.7% in chlorophyll content, and 164 and 250% in total fresh weight, respectively. Alternating applications of these products with Procure 480SC resulted in significantly less powdery mildew disease than in the water control. In the first field trial on summer squash, all products applied individually or in alternation with Procure 480SC significantly reduced the severity of powdery mildew at the early stage (60 days after planting [DAP]) of disease development. Moreover, these alternating treatments resulted in significantly better control than with Procure 480SC alone at the late assessment stage (88 DAP). The products in alternation with Procure 480SC had a level of disease reduction equivalent to Procure 480SC alone on cantaloupe and significantly reduced disease severity in comparison with the water control. Compared with applying the microbial products alone, alternating applications of these products with Procure 480SC significantly reduced disease severity on cantaloupe and improved the marketable fruit number and weight. The data from our studies suggest that these microbial products could be effectively incorporated into disease management programs. In particular, these microbial products could be integrated into the management of powdery mildew on summer squash and cantaloupe in Florida by alternating their application with low rates of conventional fungicides, potentially reducing the development of fungicide resistance in the pathogen population.
A Sida sp. Is a New Host for “Candidatus Phytoplasma brasiliense” in Brazil
Authors: Eckstein B. , Barbosa J. C. , Rezende J. A. M. , Bedendo I. P.
Published: December 2010

Sida is a genus of flowering herbs in the family Malvaceae, which includes several species that are weeds in Brazil. Plants of a Sida sp. exhibiting symptoms characterized by stunting, chlorosis, small leaves, and witches'-broom, indicative of infection by phytoplasmas, were found in a field previously cultivated with tomato, located in the region of Campinas, State of São Paulo, in December 2008. To demonstrate the presence of phytoplasmas in diseased tissues, DNA was extracted from shoots and leaves from three symptomatic and eight asymptomatic plants. Nested PCR was performed using primers P1/Tint followed by primer pair R16F2n/R16R2 (1). DNA fragments of 1.2 kb, corresponding to 16S rDNA, were amplified only for DNA from two symptomatic samples. Phytoplasma identification was initially carried out by restriction fragment length polymorphism (RFLP) analysis through digesting the PCR products with the restriction enzymes AluI, HhaI, HaeIII, HpaII, MseI, and RsaI. The two phytoplasma isolates found to be infecting a Sida sp. showed identical RFLP patterns, which were indistinguishable from the phytoplasma previously reported in association with hibiscus (Hibiscus rosa-sinensis) witches'-broom in Brazil (2). Nucleotide sequence alignment revealed that 16S rDNA of both phytoplasma isolates found in a Sida sp. (GenBank Accession No. HQ230579) shared 99.9% sequence similarity with 16S rDNA from hibiscus witches'-broom phytoplasma (HibWB) (GenBank Accession No. AF147708). HibWB is the representative of the 16SrXV group and it was proposed as a putative species nominated “Candidatus Phytoplasma brasiliense” (2). The disease is frequently observed in hibiscus plants used as ornamentals in the states of São Paulo (4) and Rio de Janeiro (2). “Ca. Phytoplasma brasiliense” has only been reported in Brazil to be infecting hibiscus (2,4) and periwinkle (Catharanthus roseus) (3). The presence of a phytoplasma belonging to group 16SrXV in a Sida sp. expands its natural host range. The role of this weed as a potential source of inoculum for crops should be investigated.

References: (1) I. M. Lee et al. Int. J. Syst. Bacteriol. 48:1153, 1998. (2) H. G. Montano et al. Int. J. Syst. Evol. Microbiol. 51:1109, 2001. (3) H. G. Montano et al. Plant Dis. 85:1209, 2001. (4) E. G. Silva et al. Summa Phytopathol. 35:234, 2009.
Models for Predicting Potential Yield Loss of Wheat Caused by Stripe Rust in the U.S. Pacific Northwest
Authors: Sharma-Poudyal D. , Chen X. M.
Published: December 2010

Climatic variation in the U.S. Pacific Northwest (PNW) affects epidemics of wheat stripe rust caused by Puccinia striiformis f. sp. tritici. Previous models only estimated disease severity at the flowering stage, which may not predict the actual yield loss. To identify weather factors correlated to stripe rust epidemics and develop models for predicting potential yield loss, correlation and regression analyses were conducted using weather parameters and historical yield loss data from 1993 to 2007 for winter wheat and 1995 to 2007 for spring wheat. Among 1,376 weather variables, 54 were correlated to yield loss of winter wheat and 18 to yield loss of spring wheat. Among the seasons, winter temperature variables were more highly correlated to wheat yield loss than the other seasons. The sum of daily temperatures and accumulated negative degree days of February were more highly correlated to winter wheat yield loss than the other monthly winter variables. In addition, the number of winter rainfall days was found correlated with yield loss. Six yield loss models were selected for each of winter and spring wheats based on their better correlation coefficients, time of weather data availability during the crop season, and better performance in validation tests. Compared with previous models, the new system of using a series of the selected models has advantages that should make it more suitable for forecasting and managing stripe rust in the major wheat growing areas in the U.S. PNW, where the weather conditions have become more favorable to stripe rust.