bluuebunny/crossref_metadata_2025 huggingface dataset:
Body dissatisfaction, maternal appraisal, and depressive symptoms in Hong Kong adolescents
Authors: Fung Samantha S. W. , Stewart Sunita M. , Ho S. Y. , Wong Joy P. S. , Lam T. H.
Published: July 2010

Body dissatisfaction, its risk factors and association with depressed mood have been well investigated in the West. However, more studies are needed to examine further the relation between body dissatisfaction and depressive symptoms and the factors influencing body dissatisfaction in non‐Western cultures. The present study examined in a sample of Hong Kong Chinese adolescents the relation between body dissatisfaction and depressive symptoms, and the relation of maternal appraisal of their adolescent's figure to the adolescent's body dissatisfaction and depressive symptoms. We obtained information from 379 boys and 254 girls about their body dissatisfaction and depressive symptoms. Their mothers provided information about their appraisal of their adolescent's body shape and size compared to ideal. Body dissatisfaction was related to depressive symptoms in girls (B = 2.58, p <.01), but not in boys (B = −0.08, p >.10). Negative maternal appraisal did not have direct effects on adolescents’ depressive symptoms (B = 0.14, p =.75), but the association between negative maternal appraisal and body dissatisfaction was significantly stronger in adolescents whose ideal was smaller than they perceived themselves to be (B = 0.32, p <.01) than those whose ideal was larger than their own perception (B = 0.14, p < .01). Our findings suggest that maternal appraisal had indirect effects on mood, acting through adolescents’ body dissatisfaction, and that body dissatisfaction may be a sex‐specific risk factor for depression. This study points to the need for testing and adapting programs to reduce body dissatisfaction particularly in girls at risk for depression, and to raise mothers’ awareness of the link between their negative appraisals and their adolescents’ body dissatisfaction and depressive symptoms.
Rapid Communication: Finding memory in search: The effect of visual working memory load on visual search
Authors: Emrich Stephen M. , Al-Aidroos Naseem , Pratt Jay , Ferber Susanne
Published: July 2010

There is now substantial evidence that during visual search, previously searched distractors are stored in memory to prevent them from being reselected. Studies examining which memory resources are involved in this process have indicated that while a concurrent spatial working memory task does affect search slopes, depleting visual working memory (VWM) resources does not. In the present study, we confirm that VWM load indeed has no effect on the search slope; however, there is an increase in overall reaction times that is directly related to the number of items held in VWM. Importantly, this effect on search time increases proportionally with the memory load until the capacity of VWM is reached. Furthermore, the search task interfered with the number of items stored in VWM during the concurrent change-detection task. These findings suggest that VWM plays a role in the inhibition of previously searched distractors.
Some classes of flexible Lie-admissible algebras
Authors: Myung Hyo Chul
Published: July 2010

Let

A

\mathfrak {A}

be a finite-dimensional, flexible, Lie-admissible algebra over a field of characteristic

≠
2

\ne 2

. Suppose that

A

−

{\mathfrak {A}^ - }

has a split abelian Cartan subalgebra

H

\mathfrak {H}

which is nil in

A

\mathfrak {A}

. It is shown that if every nonzero root space of

A

−

{\mathfrak {A}^ - }

for

H

\mathfrak {H}

is one-dimensional and the center of

A

−

{\mathfrak {A}^ - }

is 0, then

A

\mathfrak {A}

is a Lie algebra isomorphic to

A

−

{\mathfrak {A}^ - }

. This generalizes the known result obtained by Laufer and Tomber for the case that

A

−

{\mathfrak {A}^ - }

is simple over an algebraically closed field of characteristic 0 and

A

\mathfrak {A}

is power-associative. We also give a condition that a Levi-factor of

A

−

{\mathfrak {A}^ - }

be an ideal of

A

\mathfrak {A}

when the solvable radical of

A

−

{\mathfrak {A}^ - }

is nilpotent. These results yield some interesting applications to the case that

A

−

{\mathfrak {A}^ - }

is classical or reductive.
Abstract computability and its relation to the general purpose analog computer (some connections between logic, differential equations and analog computers)
Authors: Pour-el Marian Boykan
Published: July 2010

Our aim is to study computability from the viewpoint of the analog computer. We present a mathematical definition of an analog generable function of a real variable. This definition is formulated in terms of a simultaneous set of nonlinear differential equations possessing a “domain of generation.” (The latter concept is explained in the text.) Our definition includes functions generated by existing general-purpose analog computers. Using it we prove two theorems which provide a characterization of analog generable functions in terms of solutions of algebraic differential polynomials. The characterization has two consequences. First we show that there are entire functions which are computable (in the sense of recursive analysis) but which cannot be generated by any analog computer in any interval—e.g.

1

/

Γ
(
x
)

1/\Gamma (x)

and

Σ

n
=
1

∞

(

x
n

/

n

(

n
3

)

)

\Sigma _{n = 1}^\infty ({x^n}/{n^{({n^3})}})

. Second we note that the class of analog generable functions is very large: it includes special functions which arise as solutions to algebraic differential polynomials. Although not all computable functions are analog generable, a kind of converse holds. For entire functions,

f
(
x
)
=

Σ

i
=
0

∞

b
i

x
i

f(x) = \Sigma _{i = 0}^\infty {b_i}{x^i}

, the theorem takes the following form. If

f
(
x
)

f(x)

is analog generable on some closed, bounded interval then there is a finite number of

b
k

{b_k}

such that, on every closed bounded interval,

f
(
x
)

f(x)

is computable relative to these

b
k

{b_k}

. A somewhat similar theorem holds if

f
f

is not entire. Although the results are stated and proved for functions of a real variable, they hold with minor modifications for functions of a complex variable.
On Borel mappings and Baire functions
Authors: Hansell R. W.
Published: July 2010

This paper studies conditions under which classes of Borel mappings (i.e., mappings such that the inverse image of open sets are Borel sets) coincide with certain classes of Baire functions (i.e., functions which belong to the smallest family containing the continuous functions and closed with respect to pointwise limits). Generalizations of the classical Lebesgue-Hausdorff and Banach theorems are obtained for the class of mappings which we call “

σ
\sigma

-discrete". These results are then applied to the problem of extending Borel mappings over Borel sets, and generalizations of the theorems of Lavrentiev and Kuratowski are obtained.
An approach to fixed-point theorems on uniform spaces
Authors: Tarafdar E.
Published: July 2010

Diaz and Metcalf [2] have some interesting results on the set of successive approximations of a self mapping which is either a nonexpansion or a contraction on a metric space with respect to the set of fixed points of the mapping. We have extended most of these results to a Hausdorff uniform space. We have also proved a Banach’s contraction mapping principle on a complete Hausdorff uniform space and indicated some applications in locally convex linear topological spaces.
Semigroups of operators on locally convex spaces
Authors: Babalola V. A.
Published: July 2010

Let

X
X

be a complex Hausdorff locally convex topological linear space and

L
(
X
)

L(X)

the family of all continuous linear operators on

X
X

. This paper discusses the generation and perturbation theory for

C
0

{C_0}

semigroups

{
S
(
ξ
)
:
ξ
⩾
0
}
⊂
L
(
X
)

\{ S(\xi ):\xi \geqslant 0\} \subset L(X)

such that for each continuous seminorm

p
p

on

X
X

there exist a positive number

σ
p

{\sigma _p}

and a continuous seminorm

q
q

on

X
X

with

p
(
S
(
ξ
)
x
)
⩽

e

σ

p
ξ

q
(
x
)

p(S(\xi )x) \leqslant {e^{^\sigma {p^\xi }}}q(x)

for all

ξ
⩾
0

\xi \geqslant 0

and

x
∈
X

x \in X

. These semigroups are studied by means of a realization of

X
X

as a projective limit of Banach spaces, using certain naturally-defined operators and

C
0

{C_0}

semigroups on these Banach spaces to connect the present results to the classical Hille-Yosida-Phillips theory.
Identities involving the coefficients of a class of Dirichlet series. VII
Authors: Berndt Bruce C.
Published: July 2010

Let

a
(
n
)

a(n)

be an arithmetical function, and consider the Riesz sum
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper A Subscript rho Baseline left-parenthesis x right-parenthesis equals normal upper Sigma Subscript n less-than-or-equal-to x Baseline a left-parenthesis n right-parenthesis left-parenthesis x minus n right-parenthesis Superscript rho">

A
ρ

(
x
)
=

Σ

n
≤
x

a
(
n
)

(
x
−
n

)
ρ

{A_\rho }(x) = {\Sigma _{n \leq x}}a(n){(x - n)^\rho }

. For

a
(
n
)

a(n)

belonging to a certain class of arithmetical functions,

A
ρ

(
x
)

{A_\rho }(x)

can be expressed in terms of an infinite series of Bessel functions. K. Chandrasekharan and R. Narasimhan have established this identity for the widest known range of

ρ
\rho

. Their proof depends upon equi-convergence theory of trigonometric series. An alternate proof is given here which uses only the classical theory of Bessel functions.
Approximate isometries on finite dimensional Banach spaces
Authors: Bourgin Richard D.
Published: July 2010

A map

T
:

E

1

→

E

2

T:{{\mathbf {E}}_1} \to {{\mathbf {E}}_2}

(

E

1

,

E

2

{{\mathbf {E}}_1},{{\mathbf {E}}_2}

Banach spaces) is an

ϵ
\epsilon

-isometry if
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="StartAbsoluteValue EndAbsoluteValue StartAbsoluteValue upper T left-parenthesis upper X right-parenthesis minus upper T left-parenthesis upper Y right-parenthesis EndAbsoluteValue StartAbsoluteValue minus EndAbsoluteValue StartAbsoluteValue upper X minus upper Y EndAbsoluteValue StartAbsoluteValue EndAbsoluteValue less-than-or-slanted-equals epsilon">

|

|

|

T
(
X
)
−
T
(
Y
)

|

|

−

|

|

X
−
Y

|

|

|

⩽
ϵ

|\;||T(X) - T(Y)|| - ||X - Y||\;| \leqslant \epsilon

whenever

X
,
Y
∈

E

1

X,Y \in {{\mathbf {E}}_1}

. The problem of uniformly approximating such maps by isometries was first raised by Hyers and Ulam in 1945 and subsequently studied for special infinite dimensional Banach spaces. This question is here broached for the class of finite dimensional Banach spaces. The only positive homogeneous candidate isometry

U
U

approximating a given

ϵ
\epsilon

-isometry

T
T

is defined by the formal limit

U
(
X
)
=

lim

r
→
∞

r

−
1

T
(
r
X
)

U(X) = {\lim _{r \to \infty }}{r^{ - 1}}T(rX)

. It is shown that, whenever

T
:

E

→

E

T:{\mathbf {E}} \to {\mathbf {E}}

is a surjective

ϵ
\epsilon

-isometry and

E

{\mathbf {E}}

is a finite dimensional Banach space for which the set of extreme points of the unit ball is totally disconnected, then this limit exists. When

E

=

ℓ
1
k

(
=
k
- dimensional

ℓ
1

)

{\mathbf {E}} = \ell _1^k( = k \text {- dimensional}\; {\ell _1})

a uniform bound of uniform approximation is obtained for surjective

ϵ
\epsilon

-isometries by isometries; this bound varies linearly in

ϵ
\epsilon

and with

k
3

{k^3}

.
A study of graph closed subsemigroups of a full transformation semigroup
Authors: Biggs R. G. , Rankin S. A. , Reis C. M.
Published: July 2010

Let

T
X

{T_X}

be the full transformation semigroup on the set X and let S be a subsemigroup of

T
X

{T_X}

. We may associate with S a digraph

g
(
S
)

g(S)

with X as set of vertices as follows:

i
→
j
∈
g
(
S
)

i \to j \in g(S)

iff there exists

α
∈
S

\alpha \in S

such that

α
(
i
)
=
j

\alpha (i) = j

. Conversely, for a digraph G having certain properties we may assign a semigroup structure,

S
(
G
)

S(G)

, to the underlying set of G. We are thus able to establish a “Galois correspondence” between the subsemigroups of

T
X

{T_X}

and a particular class of digraphs on X. In general, S is a proper subsemigroup of

S
⋅
g
(
S
)

S \cdot g(S)

.
A quasi-Anosov diffeomorphism that is not Anosov
Authors: Franks John , Robinson Clark
Published: July 2010

In this note, we give an example of a diffeomorphism f on a three dimensional manifold M such that f has a property called quasi- Anosov but such that f does not have a hyperbolic structure (is not Anosov). Mañé has given a method of extending f to a diffeomorphism g on a larger dimensional manifold V such that g has a hyperbolic structure on M as a subset of V. This gives a counterexample to a question of M. Hirsch.
The isomorphism problem for two-generator one-relator groups with torsion is solvable
Authors: Pride Stephen J.
Published: July 2010

The theorem stated in the title is obtained by determining (in a sense to be made precise) all the generating pairs of an arbitrary two-generator one-relator group with torsion. As a consequence of this determination it is also deduced that every two-generator one-relator group G with torsion is Hopfian, and that the automorphism group of G is finitely generated.
Unimodality and dominance for symmetric random vectors
Authors: Kanter Marek
Published: July 2010

In this paper a notion of unimodality for symmetric random vectors in

R
N

{R^N}

is developed which is closed under convolution as well as weak convergence. A related notion of stochastic dominance for symmetric random vectors is also studied.
Quasi-Anosov diffeomorphisms and hyperbolic manifolds
Authors: Mañé Ricardo
Published: July 2010

Let f be a diffeomorphism of a smooth manifold N and

M
⊂
N

M \subset N

a compact boundaryless submanifold such that it is a hyperbolic set for f. The diffeomorphism f/M is characterized and it is proved that it is Anosov if and only if M is an invariant isolated set of f (i.e. the maximal invariant subset of some compact neighborhood). Isomorphisms of vector bundles with the property that the zero section is an isolated subset are studied proving that they can be embedded in hyperbolic vector bundle isomorphisms.
Relativized weak disjointness and relatively invariant measures
Authors: McMahon Douglas C.
Published: July 2010

In this paper we study the relativized weak disjointness and the relativized regionally proximal relation for homomorphisms of point-transitive transformation groups, under the assumption of a relativized invariant measure. We also include a proof of a Folner-type result for syndetic subsets of an amenable group.
Isosingular loci and the Cartesian product structure of complex analytic singularities
Authors: Ephraim Robert
Published: July 2010

Let X be a (not necessarily reduced) complex analytic space, and let V be a germ of an analytic space. The locus of points q in X at which the germ

X
q

{X_q}

is complex analytically isomorphic to V is studied. If it is nonempty it is shown to be a locally closed submanifold of X, and X is locally a Cartesian product along this submanifold. This is used to define what amounts to a coarse partial ordering of singularities. This partial ordering is used to show that there is an essentially unique way to completely decompose an arbitrary reduced singularity as a cartesian product of lower dimensional singularities. This generalizes a result previously known only for irreducible singularities.
The rigidity of graphs
Authors: Asimow L. , Roth B.
Published: July 2010

We regard a graph G as a set

{
1
,
…
,
v
}

\{ 1, \ldots , v \}

together with a nonempty set E of two-element subsets of

{
1
,
…
,
v
}

\{ 1, \ldots , v \}

. Let

p
=
(

p
1

,
…
,

p
v

)

p = ({p_1},\ldots ,{p_v})

be an element of

R

n
v

{\textbf {R}^{nv}}

representing v points in

R

n

{\textbf {R}^n}

. Consider the figure

G
(
p
)

G(p)

in

R

n

{\textbf {R}^n}

consisting of the line segments

[

p
i

,

p
j

]

[{p_i},{p_j}]

in

R

n

{\textbf {R}^n}

for

{
i
,
j
}
∈
E

\{ i,j\} \in E

. The figure

G
(
p
)

G(p)

is said to be rigid in

R

n

{\textbf {R}^n}

if every continuous path in

R

n
v

{\textbf {R}^{nv}}

, beginning at p and preserving the edge lengths of

G
(
p
)

G(p)

, terminates at a point

q
∈

R

n
v

q \in {\textbf {R}^{nv}}

which is the image

(
T

p
1

,
…
,
T

p
v

)

(T{p_1}, \ldots ,T{p_v})

of p under an isometry T of

R

n

{\textbf {R}^n}

. Otherwise,

G
(
p
)

G(p)

is flexible in

R

n

{\textbf {R}^n}

. Our main result establishes a formula for determining whether

G
(
p
)

G(p)

is rigid in

R

n

{\textbf {R}^n}

for almost all locations p of the vertices. Applications of the formula are made to complete graphs, planar graphs, convex polyhedra in

R

3

{\textbf {R}^3}

, and other related matters.
A simultaneous lifting theorem for block diagonal operators
Authors: Allen G. D. , Ward J. D.
Published: July 2010

Stampfli has shown that for a given

T

∈

B

(
H
)

T\, \in \,B\left ( H \right )

there exists a

K

∈

C

(
H
)

K\, \in \,C\left ( H \right )

so that

σ

(

T

+

K

)

=

σ
w

(
T
)

\sigma \left ( {T\, + \, K} \right )\,= \,{\sigma _w}\left ( T \right )

. An analogous result holds for the essential numerical range

W
e

(
T
)

{W_e}\left ( T \right )

. A compact operator K is said to preserve the Weyl spectrum and essential numerical range of an operator

T

∈

B

(
H
)

T\, \in \,B\left ( H \right )

if

σ

(

T

+

K

)

=

σ
w

(
T
)

\sigma \left ( {T\, + \, K} \right )\, = \,{\sigma _w}\left ( T \right )

and

W

(

T

+

K

)

¯

=

W
e

(
T
)

\overline {W\left ( {T \, + \, K} \right )} \, = \,{W_e}\left ( T \right )

. Theorem. For each block diagonal operator T, there exists a compact operator K which preserves the Weyl spectrum and essential numerical range of T. The perturbed operator

T

+

K

T \, + \, K

is not, in general, block diagonal. An example is given of a block diagonal operator T for which there can be no block diagonal perturbation which preserves the Weyl spectrum and essential numerical range of T.
On the Littlewood-Paley theory for mixed norm spaces
Authors: Gosselin John A.
Published: July 2010

An inequality of Littlewood-Paley type is proved for the mixed norm spaces

L
P

(

l
r

)

{L_P}({l_r})

,

1
>
p

1 > p

,

r
>
∞

r > \infty

, on the interval

[
0
,
1
]

[0,1]

. This result makes use of recent work by C. Fefferman and A. Cordoba on the boundedness of singular integrals on these spaces. As an application of this inequality, boundedness of the lacunary maximal partial sum operator for Walsh-Fourier series on

L
p

(

l
r

)

{L_p}({l_r})

is established. This result can be viewed as an extension of a similar result for the Hardy-Littlewood maximal function due to C. Fefferman and E. M. Stein.
Cloud-Coffee: implementation of a parallel consistency-based multiple alignment algorithm in the T-Coffee package and its benchmarking on the Amazon Elastic-Cloud
Authors: Di Tommaso Paolo , Orobitg Miquel , Guirado Fernando , Cores Fernado , Espinosa Toni , Notredame Cedric
Published: July 2010

Summary: We present the first parallel implementation of the T-Coffee consistency-based multiple aligner. We benchmark it on the Amazon Elastic Cloud (EC2) and show that the parallelization procedure is reasonably effective. We also conclude that for a web server with moderate usage (10K hits/month) the cloud provides a cost-effective alternative to in-house deployment.

Availability: T-Coffee is a freeware open source package available from http://www.tcoffee.org/homepage.html

Contact:  cedric.notredame@crg.es
MamPhEA: a web tool for mammalian phenotype enrichment analysis
Authors: Weng Meng-Pin , Liao Ben-Yang
Published: July 2010

Summary: MamPhEA is a web application dedicated to understanding functional properties of mammalian gene sets based on mouse-mutant phenotypes. It allows users to conduct enrichment analysis on predefined or user-defined phenotypes, gives users the option to specify phenotypes derived from null mutations, produces easily comprehensible results and supports analyses on genes of all mammalian species with a fully sequenced genome.

Availability:  http://evol.nhri.org.tw/MamPhEA/

Contact:  liaoby@nhri.org.tw

Supplementary information:  Supplementary data are available at Bioinformatics online.
Aggressiveness of Phytophthora cactorum, P. citricola I, and P. plurivora from European Beech
Authors: Weiland Jerry E. , Nelson Angela H. , Hudler George W.
Published: July 2010

Phytophthora cactorum, P. citricola I, and P. plurivora cause bleeding cankers on mature European beech (Fagus sylvatica) trees in the northeastern United States. Inoculation experiments were conducted to compare the aggressiveness of the three Phytophthora spp. on stems, leaf disks, and roots of European beech and common lilac (Syringa vulgaris) seedlings. Isolates were obtained from bleeding cankers on European beech from five cities in New York (Albany, Ithaca, Oyster Bay, Plainview, and Rochester) and from a bleeding canker on sugar maple in Ithaca, NY. Stems were inoculated with colonized agar plugs, leaf disks with a zoospore suspension, and roots via infested soil at three inoculum levels. All organs of inoculated beech and lilac developed disease except for lilac roots inoculated with zoospores of P. cactorum. Disease incidence, severity, and plant survival were dependent on isolate and were also influenced by the tissue inoculated and host. Isolates of P. cactorum were the least aggressive and caused less necrosis than isolates of P. citricola I and P. plurivora. Results emphasize the utility of stem and root inoculation for evaluation of this canker disease and underscore critical differences in species aggressiveness.
Lumbar Intrathecal Administration of the Quaternary Lidocaine Derivative, QX-314, Produces Irritation and Death in Mice
Authors: Schwarz Stephan K. W. , Cheung Helen M.-C. , Ries Craig R. , Lee Sang Mook , Wang Jimmy T. C. , MacLeod Bernard A.
Published: July 2010

Background

We recently found that peripheral administration of the quaternary lidocaine derivative, QX-314, produces long-lasting sensory and motor blockade in animals. The goal of this study was to test whether intrathecal QX-314 has similar properties.

Methods

We conducted a randomized, double-controlled, blinded study with female CD-1 mice. Animals in the treatment group received lumbar intrathecal QX-314 (0.5-10 mM; volume, 2 microl; each concentration, n = 6). Normal saline and lidocaine (70 mM) served as negative and positive controls (each group, n = 12), respectively. Animals were tested for up to 3 h for lumbosacral neural blockade and observed for adverse effects.

Results

No animal injected with saline and 11 of 12 (92%) animals injected with lidocaine displayed reversible lumbosacral motor blockade (P < 0.001). QX-314 (5 mM) produced motor blockade in four of the six (67%) and sensory blockade in five of the six animals (83%; P < 0.05 vs. saline). However, six of the six mice (100%) at 5 mM QX-314 and five of the six (83%) at 10 mM exhibited marked irritation; one of the six animals at 5 mM (17%) and two of the six at 10 mM (33%) died. We observed no neural blockade without adverse effects in any animal injected with QX-314. All animals injected with saline and 11 of the 12 (92%) animals injected with lidocaine demonstrated normal behavior.

Conclusion

Lumbar intrathecal QX-314 concentration-dependently produced irritation and death in mice, at lower concentrations than those associated with robust motor blockade. Although QX-314 did produce long-lasting neural blockade, these findings indicate that QX-314 is unlikely to be a suitable candidate for spinal anesthesia in humans.
Visual P2–N2 Complex and Arousal at the Time of Encoding Predict the Time Domain Characteristics of Amnesia for Multiple Intravenous Anesthetic Drugs in Humans
Authors: Pryor Kane O. , Reinsel Ruth A. , Mehta Meghana , Li Yuelin , Wixted John T. , Veselis Robert A.
Published: July 2010

Background

Intravenous anesthetics have marked effects on memory function, even at subclinical concentrations. Fundamental questions remain in characterizing anesthetic amnesia and identifying affected system-level processes. The authors applied a mathematical model to evaluate time-domain components of anesthetic amnesia in human subjects.

Methods

Sixty-one volunteers were randomized to receive propofol (n = 12), thiopental (n = 13), midazolam (n = 12), dexmedetomidine (n = 12), or placebo (n = 12). With drug present, subjects encoded pictures into memory using a 375-item continuous recognition task, with subsequent recognition later probed with drug absent. Memory function was sampled at up to 163 time points and modeled over the time domain using a two-parameter, first-order negative power function. The parietal event-related P2-N2 complex was derived from electroencephalography, and arousal was repeatedly sampled. Each drug was evaluated at two concentrations.

Results

The negative power function consistently described the course of amnesia (mean R = 0.854), but there were marked differences between drugs in the modulation of individual components (P < 0.0001). Initial memory strength was a function of arousal (P = 0.005), whereas subsequent decay was related to the reaction time (P < 0.0001) and the P2-N2 complex (P = 0.007/0.002 for discrete components).

Conclusions

In humans, the amnesia caused by multiple intravenous anesthetic drugs is characterized by arousal-related effects on initial trace strength, and a subsequent decay predicted by attenuation of the P2-N2 complex at encoding. The authors propose that the failure of normal memory consolidation follows drug-induced disruption of interregional synchrony critical for neuronal plasticity and discuss their findings in the framework of memory systems theory.
Oxygen and Surgical Site Infection
Authors: Qadan Motaz , Battista Christopher , Gardner Sarah A. , Anderson Gary , Akca Ozan , Polk Hiram C.
Published: July 2010

Background

Recent clinical trials investigating the role of hyperoxia in decreasing surgical site infection have reported conflicting results. Immunologic mechanisms through which supplemental oxygen could act have not been elucidated fully. The authors sought to investigate the effects of hyperoxia on previously tested and prognostically significant innate immune parameters to uncover the potential effects of hyperoxia at the cellular level.

Methods

After formal approval and informed consent, venous blood samples were collected from young healthy volunteers. Corresponding samples were incubated at 21 or 80% O2 following a 1 ng/ml lipopolysaccharide challenge and analyzed to determine human leukocyte antigen-DR surface receptor expression, cytokine release, phagocytic capacity, and formation of reactive oxygen species. Data are presented as mean +/- SD.

Results

After the 2 h of incubation at 21% O2 (room air) and in 80% O2 chambers, the change in human leukocyte antigen-DR mean channel fluorescence in lipopolysaccharide-stimulated monocytes was 2,177 +/- 383 and 2,179 +/- 338 (P = 0.96), respectively. Tumor necrosis factor-alpha concentrations were significantly lower for samples incubated at 80% O2 when compared with 21% O2 (P < 0.05). The phagocytic capacity of the innate immune system was not significantly enhanced by supplemental oxygen. However, the formation of reactive oxygen species increased by 87% (P < 0.05).

Conclusion

Hyperoxia exerts significant effects on multiple cellular and immunologic parameters, providing a potential mechanism for benefits from the use of supplemental oxygen. However, the ability to translate positive basic scientific findings to the operating suite or bedside require the existence of similar innate immune processes in vivo and the efficient transfer of oxygen to the sites where it may be used.
Analgesic and Antihyperalgesic Properties of Propofol in a Human Pain Model
Authors: Bandschapp Oliver , Filitz Joerg , Ihmsen Harald , Berset Andreas , Urwyler Albert , Koppert Wolfgang , Ruppen Wilhelm
Published: July 2010

Background

Propofol (Disoprivan, AstraZeneca AG, Zug, Switzerland) has long been considered to be nonanalgesic. However, accumulating evidence shows that propofol possesses modulatory action on pain processing and perception. In this study, the authors investigated the modulatory effects of propofol and a formulation similar to the solvent of propofol (10% Intralipid; Fresenius Kabi, Stans, Switzerland) on pain perception and central sensitization in healthy volunteers.

Methods

Fourteen healthy volunteers were included in this randomized, double-blind, placebo-controlled, crossover study. Intracutaneous electrical stimulation (48.8 +/- 25.8 mA) induced spontaneous acute pain (Numeric Rating Scale, 6 of 10) and stable areas of hyperalgesia and allodynia. Pain intensities and areas of hyperalgesia were assessed regularly before, during, and after a 45-min target-controlled infusion (2 microg/ml) of propofol, the solvent 10% Intralipid, and saline.

Results

During administration, propofol significantly decreased pain scores and areas of hyperalgesia and allodynia compared with both 10% Intralipid and saline (placebo-corrected mean Numerical Rating Scale score reduction by propofol: 38 +/- 28%). This difference disappeared shortly after cessation of the infusion. Thereafter, no significant group differences were observed in the Numerical Rating Scale score and the areas of hyperalgesia or allodynia. However, there was a trend to reduced hyperalgesia and allodynia after propofol treatment. Pharmacodynamic modeling regarding the analgesic effect of propofol showed an EC50 (half-maximum effect site concentration) of 3.19 +/- 0.37 microg/ml. Ten percent Intralipid was free of pain-modulatory effects in the authors' experiments.

Conclusions

Propofol showed short-lasting analgesic properties during its administration, whereas the solvent-like formulation 10% Intralipid had no effect on pain perception.
Preoperative Prolonged Steroid Use Is Not Associated with Intraoperative Blood Transfusion in Noncardiac Surgical Patients
Authors: Turan Alparslan , Dalton Jarrod E. , Turner Patricia L. , Sessler Daniel I. , Kurz Andrea , Saager Leif
Published: July 2010

Background

Prolonged steroid therapy is reportedly associated with changes in coagulation, suggesting increased intraoperative bleeding or hypercoagulability. The aim of this retrospective study was to assess whether long-term steroid use was associated with increased transfusion requirements, infection, or hypercoagulability in adults undergoing noncardiac surgery.

Methods

In this study the authors evaluated 363,897 patients from the American College of Surgeons National Surgical Quality Improvement Program database. Patients with current pneumonia, ventilator dependence, coma, tumor involving the central nervous system, disseminated cancer, preoperative open wound/wound infection, and/or bleeding disorders were excluded. Each steroid user was matched to a nonsteroid user based on propensity score and type of surgery.

Results

296,059 patients met the inclusion criteria, of whom 7,760 (2.6%) were taking steroids preoperatively. The incidence of intraoperative erythrocyte transfusion was 3.6% in the steroid user and 7.3% in non-steroid-user groups. After matching, the mean [95% confidence interval] number of units transfused was 0.22 [0.19, 0.25] units in the nonsteroid group and 0.19 [0.17, 0.22] units in the steroid group which was not statistically significant (P = 0.24, Wald test). Steroid users were 24% [2, 49] more likely to experience 30-day postoperative systemic infection and 21% [3, 41] more likely to experience postoperative wound infection than nonusers. The risks of postoperative thromboembolic complications did not differ significantly.

Conclusions

The effect of prolonged steroid use on bleeding, if any, thus seems likely to be small and is probably of limited clinical consequence. In contrast, corticosteroid use augments the risk of both systemic and wound infections.
Dexmedetomidine in the Care of Critically Ill Patients from 2001 to 2007
Authors: Wunsch Hannah , Kahn Jeremy M. , Kramer Andrew A. , Wagener Gebhard , Li Guohua , Sladen Robert N. , Rubenfeld Gordon D.
Published: July 2010

Background

Dexmedetomidine is a novel sedative agent that causes anxiolysis without respiratory depression in critically ill patients. We sought to examine patient and hospital variation in dexmedetomidine use and adoption patterns of dexmedetomidine over time.

Methods

We performed a retrospective cohort study of all patients who received intravenous infusion sedation in 174 intensive care units contributing data to Project IMPACT from 2001 through 2007. Sedation use was defined as having received an intravenous sedative infusion (dexmedetomidine, midazolam, lorazepam, or propofol) for any period during the intensive care stay. The primary outcome was use of dexmedetomidine in the intensive care unit.

Results

Of 58,391 patients who received intravenous infusion sedation, 2,535 (4.3%, 95% confidence interval [CI], 4.2-4.5) received dexmedetomidine. Overall use was highest in cardiac surgery patients (11.7%, 10.8-12.7) and was similar in other surgical patients (4.3%, 4.0-4.6) and medical patients (3.4%, 3.2-3.6, P < 0.001). Use of dexmedetomidine increased from 2.0% (1.6-2.4) of patients receiving intravenous infusion sedation in 2001 to 7.2% (6.6-7.9) in 2007 (P < 0.001), primarily because of an increase in use in cardiac surgery patients (1.4%, 0.0-2.8, in 2001 vs. 20.2%, 17.6-22.8 in 2007, P < 0.001). Of the patients who received dexmedetomidine, 31.5% (29.6-33.3) received the infusion for more than 1 day, and 10.9% were not mechanically ventilated.

Conclusion

Use of dexmedetomidine in critically ill patients has increased over time, primarily as a result of an increase in use among cardiac surgery patients. A substantial portion of dexmedetomidine was administered outside of the regulatory approval guidelines at the time.
Increase of Oxygen Consumption during a Progressive Decrease of Ventilatory Support Is Lower in Patients Failing the Trial in Comparison with Those Who Succeed
Authors: Bellani Giacomo , Foti Giuseppe , Spagnolli Ester , Milan Manuela , Zanella Alberto , Greco Massimilano , Patroniti Nicolò , Pesenti Antonio
Published: July 2010

Background

The aim of this study was to test the hypothesis that, during weaning from mechanical ventilation, when the pressure support level is reduced, oxygen consumption increases more in patients unable to sustain the decrease in ventilatory assistance (weaning failure).

Methods

Patients judged eligible for weaning were enrolled. Starting from 20 cm H2O, pressure support was decreased in 4-cm H2O steps, lasting 10 min each, until 0 cm H2O; this level was kept for 1 h. The average oxygen consumption from the last 3 min of each step, along with other ventilatory variables, was measured by indirect calorimetry (M-CAiOVX "metabolic module," Engstrom Carestation; GE Healthcare, Madison, WI) and recorded. Patients were defined as belonging to the failure group if, at any moment, they developed signs of respiratory distress according to standard criteria, or to the success group otherwise.

Results

Twenty-eight patients were studied. In most patients, the minimum oxygen consumption was not recorded at the highest pressure support applied. Sixteen patients were able to complete the weaning trial successfully, whereas 12 failed it; the success group had a minimum oxygen consumption lower than failure group (mean +/- SD: 174 +/- 44 vs. 215 +/- 53 ml/min, P < 0.05). Moreover, although respiratory drive (assessed by P0.1) increased more in the failure group, this group had a lower increase in oxygen consumption, contradicting our hypothesis.

Conclusions

Patients failing a decremental pressure support trial, in comparison with those who succeed, had an higher baseline oxygen consumption and were not able to increase their oxygen consumption in response to an increased demand.
Overexpression of the Epidermis-Specific Homeodomain-Leucine Zipper IV Transcription Factor OUTER CELL LAYER1 in Maize Identifies Target Genes Involved in Lipid Metabolism and Cuticle Biosynthesis
Authors: Javelle Marie , Vernoud Vanessa , Depège-Fargeix Nathalie , Arnould Christine , Oursel Delphine , Domergue Frédéric , Sarda Xavier , Rogowsky Peter M.
Published: July 2010

Transcription factors of the homeodomain-leucine zipper IV (HD-ZIP IV) family play crucial roles in epidermis-related processes. To gain further insight into the molecular function of OUTER CELL LAYER1 (OCL1), 14 target genes up- or down-regulated in transgenic maize (Zea mays) plants overexpressing OCL1 were identified. The 14 genes all showed partial coexpression with OCL1 in maize organs, and several of them shared preferential expression in the epidermis with OCL1. They encoded proteins involved in lipid metabolism, defense, envelope-related functions, or cuticle biosynthesis and include ZmWBC11a (for white brown complex 11a), an ortholog of AtWBC11 involved in the transport of wax and cutin molecules. In support of the annotations, OCL1-overexpressing plants showed quantitative and qualitative changes of cuticular wax compounds in comparison with wild-type plants. An increase in C24 to C28 alcohols was correlated with the transcriptional up-regulation of ZmFAR1, coding for a fatty acyl-coenzyme A reductase. Transcriptional activation of ZmWBC11a by OCL1 was likely direct, since transactivation in transiently transformed maize kernels was abolished by a deletion of the activation domain in OCL1 or mutations in the L1 box, a cis-element bound by HD-ZIP IV transcription factors. Our data demonstrate that, in addition to AP2/EREBP and MYB-type transcription factors, members of the HD-ZIP IV family contribute to the transcriptional regulation of genes involved in cuticle biosynthesis.
Enzymatic Functions of Wild Tomato Methylketone Synthases 1 and 2
Authors: Yu Geng , Nguyen Thuong T.H. , Guo Yongxia , Schauvinhold Ines , Auldridge Michele E. , Bhuiyan Nazmul , Ben-Israel Imri , Iijima Yoko , Fridman Eyal , Noel Joseph P. , Pichersky Eran
Published: July 2010

The trichomes of the wild tomato species Solanum habrochaites subsp. glabratum synthesize and store high levels of methylketones, primarily 2-tridecanone and 2-undecanone, that protect the plants against various herbivorous insects. Previously, we identified cDNAs encoding two proteins necessary for methylketone biosynthesis, designated methylketone synthase 1 (ShMKS1) and ShMKS2. Here, we report the isolation of genomic sequences encoding ShMKS1 and ShMKS2 as well as the homologous genes from the cultivated tomato, Solanum lycopersicum. We show that a full-length transcript of ShMKS2 encodes a protein that is localized in the plastids. By expressing ShMKS1 and ShMKS2 in Escherichia coli and analyzing the products formed, as well as by performing in vitro assays with both ShMKS1and ShMKS2, we conclude that ShMKS2 acts as a thioesterase hydrolyzing 3-ketoacyl-acyl carrier proteins (plastid-localized intermediates of fatty acid biosynthesis) to release 3-ketoacids and that ShMKS1 subsequently catalyzes the decarboxylation of these liberated 3-ketoacids, forming the methylketone products. Genes encoding proteins with high similarity to ShMKS2, a member of the “hot-dog fold” protein family that is known to include other thioesterases in nonplant organisms, are present in plant species outside the genus Solanum. We show that a related enzyme from Arabidopsis (Arabidopsis thaliana) also produces 3-ketoacids when recombinantly expressed in E. coli. Thus, the thioesterase activity of proteins in this family appears to be ancient. In contrast, the 3-ketoacid decarboxylase activity of ShMKS1, which belongs to the α/β-hydrolase fold superfamily, appears to have emerged more recently, possibly within the genus Solanum.
Entry Mode–Dependent Function of an Indole Glucosinolate Pathway in Arabidopsis for Nonhost Resistance against Anthracnose Pathogens
Authors: Hiruma Kei , Onozawa-Komori Mariko , Takahashi Fumika , Asakura Makoto , Bednarek Paweł , Okuno Tetsuro , Schulze-Lefert Paul , Takano Yoshitaka
Published: July 2010

When faced with nonadapted fungal pathogens, Arabidopsis thaliana mounts nonhost resistance responses, which typically result in the termination of early pathogenesis steps. We report that nonadapted anthracnose fungi engage two alternative entry modes during pathogenesis on leaves: turgor-mediated invasion beneath melanized appressoria, and a previously undiscovered hyphal tip–based entry (HTE) that is independent of appressorium formation. The frequency of HTE is positively regulated by carbohydrate nutrients and appears to be subject to constitutive inhibition by the fungal mitogen-activated protein kinase (MAPK) cascade of MAPK ESSENTIAL FOR APPRESSORIUM FORMATION1. The same MAPK cascade is essential for appressorium formation. Unexpectedly, the Arabidopsis indole glucosinolate pathway restricts entry of the nonadapted anthracnose fungi only when these pathogens employ HTE. Arabidopsis mutants defective in indole glucosinolate biosynthesis or metabolism support the initiation of postinvasion growth of nonadapted Colletotrichum gloeosporioides and Colletotrichum orbiculare. However, genetic disruption of Colletotrichum appressorium formation does not permit HTE on host plants. Thus, Colletotrichum appressoria play a critical role in the suppression of preinvasion plant defenses, in addition to their previously described role in turgor-mediated plant cell invasion. We also show that HTE is the predominant morphogenetic response of Colletotrichum at wound sites. This implies the existence of a fungal sensing system to trigger appropriate morphogenetic responses during pathogenesis at wound sites and on intact leaf tissue.
Pressure-induced phase transitions in L-alanine, revisited
Authors: Tumanov N. A. , Boldyreva E. V. , Kolesov B. A. , Kurnosov A. V. , Quesada Cabrera R.
Published: July 2010

The effect of pressure on L-alanine has been studied by X-ray powder diffraction (up to 12.3 GPa), single-crystal X-ray diffraction, Raman spectroscopy and optical microscopy (up to ∼ 6 GPa). No structural phase transitions have been observed. At ∼ 2 GPa the cell parameters a and b become accidentally equal to each other, but without a change in space-group symmetry. Neither of two transitions reported by others (to a tetragonal phase at ∼ 2 GPa and to a monoclinic phase at ∼ 9 GPa) was observed. The changes in cell parameters were continuous up to the highest measured pressures and the cells remained orthorhombic. Some important changes in the intermolecular interactions occur, which also manifest themselves in the Raman spectra. Two new orthorhombic phases could be crystallized from a MeOH/EtOH/H2O pressure-transmitting mixture in the pressure range 0.8–4.7 GPa, but only if the sample was kept at these pressures for at least 1–2 d. The new phases converted back to L-alanine on decompression. Judging from the Raman spectra and cell parameters, the new phases are most probably not L-alanine but its solvates.
Reflections on methodologies for research at the marketing/entrepreneurship interface
Authors: Gilmore Audrey
Published: July 2010

Purpose

The first issue ofJournal of Research in Marketing and Entrepreneurshipdiscusses methodologies for research at the marketing/entrepreneurship interface (MEI) in the years between 1986 and 1998, based on the published symposia proceedings (the “Blue Books” edited annually by Gerry Hills with others from 1986). The purpose of this paper is to consider research at the MEI and summarises some of the methodologies that are used in this field.

Design/methodology/approach

This paper carries out an overview of the different types of methodologies used to investigate marketing and entrepreneurship at the interface.

Findings

The paper illustrates that research at the MEI is alive and well, it has taken large strides in the last 25 years. There are a large range of research designs and methodologies to choose from and researchers are encouraged to continue to be innovative in their approaches to studying entrepreneurs/owners/managers and how, why, when and where they do business.

Originality/value

This paper shows that research continues to develop and expand at the MEI. There is much yet to learn.
The effect of corporate governance on earnings management around UK rights issues
Authors: Iqbal Abdullah , Strong Norman
Published: July 2010

Purpose

This paper aims to investigate the relation between corporate governance and earnings management around UK rights issues.

Design/methodology/approach

The paper examines the effect of board structure, ownership structure, adviser structure, and capital structure on discretionary current accruals – a proxy for earnings management – for a sample of size‐controlled rights issuers. Rights issues are chosen as a context in which firms have particular incentives to manage earnings.

Findings

The results suggest that firms with higher debt to equity ratios, with lower proportions of non‐executive directors, or with no large block owner, are more likely to use discretionary current accruals to manipulate earnings around rights issues.

Research limitations/implications

Similar research can be conducted around other equity issuing methods such as open offers and around other major corporate events such as initial public offerings.

Practical implications

The paper's evidence contributes to an understanding of corporate governance and has practical implications for stakeholders. It suggests that investors can rely more on the financial disclosures of firms with lower debt to equity ratios, higher proportions of outside directors, and with a large blockholder. Regulators may propose that firms undertaking corporate events such as equity offerings should follow best corporate governance practices to enhance investor confidence.

Originality/value

This study is the first to investigate the corporate governance mechanisms in place to check opportunistic earnings management around specific corporate events for the UK market.
Relative Importance of Intrinsic, Extrinsic, and Anthropic Factors in the Geomorphic Zonation of the Trinity River, Texas1
Authors: Phillips Jonathan D.
Published: July 2010

Phillips, Jonathan D., 2010. Relative Importance of Intrinsic, Extrinsic, and Anthropic Factors in the Geomorphic Zonation of the Trinity River, Texas. Journal of the American Water Resources Association (JAWRA) 46(4): 807‐823. DOI: 10.1111/j.1752‐1688.2010.00457.x

Abstract:  The Trinity River, Texas, was characterized according to its geologic framework, valley width and confinement, slope, sinuosity, channel‐floodplain connectivity, and flow regime, leading to the identification of 18 hinge points along the 638 km study area where major transitions in two or more criteria occur. These, and effects of human agency, avulsions, and sea level rise, delineate 21 river styles or zones. Each zone was evaluated with respect to dominant factors determining its geomorphological characteristics: geology/lithology, tectonics, Holocene sea level rise, meandering, cutoffs and other lateral channel changes, avulsions, valley constrictions by alluvial terraces, and paleomeander depressions. Direct human influences (a large impoundment and water withdrawals) are also evident. Entropy of the relationships between these controls and the geomorphological zones shows that all the controls are significant, and each accounts for 4‐15% of the total entropy. Geologic controls, lateral channel changes, and constriction by terraces are the three most influential controls, illustrating that controls on river morphology include extrinsic boundary conditions, active process‐form interrelationships, and inherited features. Extrinsic and intrinsic controls each account for about a third of the entropy, but the latter includes antecedent features as well as active channel dynamics, underscoring the importance of historical contingency even in alluvial rivers.