bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of microbiotic crusts on evaporation from the revegetated area in a Chinese desert
Authors: Liu Lichao , Song Yaoxuan , Gao Yanhong , Wang Tao , Li Xinrong
Published: September 2007

Conflicting views exist on the evaporative effects of microbiotic crusts. The effects of microbiotic crusts on evaporation were studied using a microlysimeter under different simulated precipitation. The results show that under minor precipitation, the microbiotic crusts generally act as a retarding factor for evaporation, prolonging water retention in the surface layer in comparison with sandy soil, whereas under abundant precipitation, the crusts result in less infiltration and a greater total water loss through evaporation. It is possible that microbiotic crusts act as a major environmental driver in the succession of restored vegetation through their influence on evaporative water loss.
A study of the interactions between salinity, soil erosion, and pollutant transport on three Queensland soils
Authors: Ghadiri H. , Hussein J. , Rose C. W.
Published: September 2007

The effects of salinity and sodicity on soil erosion, sediment transport, and runoff water quality were studied under the simulated rainfall using 3 soils whose salinity and sodicity were artificially raised. Soil type and salt treatment both affected sediment loss, with a significant interaction between the 2 factors. The salt treatment decreased aggregate stability, reduced aggregate mean weight diameters, and increased sediment loss for all soils, but the soil with the most stable aggregates (Redlands) showed the highest impact. The initial treatment resulted in a sharp rise in the electrical conductivity (EC) and exchangeable sodium percentage (ESP) of all 3 soils but these increases were much higher in the sandy Toohey soil than the 2 clay soils. Electrical conductivities of all 3 treated soils decreased during the rainfall events, but the Toohey soil showed the largest decrease. The ESP of the treated Toohey soil decreased rapidly during the rainfall event due to its coarse texture, rapid renewal of its pore water, and the accessibility of its exchange sites by ions in the solution. The EC of the treated Redlands clay was reduced and its ESP increased during the rainfall events, which resulted in the weakening of its stable aggregates and increased erosion. Sodium adsorption ratio and EC of runoff water from treated soils decreased rapidly with rainfall duration for all 3 soils, but runoff from Toohey showed the largest decrease. The interaction between increased salinity-sodicity and erosion thus appears to be heavily dependent on soil texture, degree of aggregation, and aggregate stability, the 3 determinant factors for soil porosity and pore-size distribution. The results indicate that large sediment and salt losses can occur in runoff from saline-sodic soils, even at low slopes and from apparently stable soils, with major downstream water quality consequences.
Predicting the response of wheat (Triticum aestivum L.) to liquid and granular phosphorus fertilisers in Australian soils
Authors: McBeath T. M. , McLaughlin M. J. , Armstrong R. D. , Bell M. , Bolland M. D. A. , Conyers M. K. , Holloway R. E. , Mason S. D.
Published: September 2007

Liquid forms of phosphorus (P) have been shown to be more effective than granular P for promoting cereal growth in alkaline soils with high levels of free calcium carbonate on Eyre Peninsula, South Australia. However, the advantage of liquid over granular P forms of fertiliser has not been fully investigated across the wide range of soils used for grain production in Australia.
A glasshouse pot experiment tested if liquid P fertilisers were more effective for growing spring wheat (Triticum aestivum L.) than granular P (monoammonium phosphate) in 28 soils from all over Australia with soil pH (H2O) ranging from 5.2 to 8.9. Application of liquid P resulted in greater shoot biomass, as measured after 4 weeks’ growth (mid to late tillering, Feeks growth stage 2–3), than granular P in 3 of the acidic to neutral soils and in 3 alkaline soils. Shoot dry matter responses of spring wheat to applied liquid or granular P were related to soil properties to determine if any of the properties predicted superior yield responses to liquid P. The calcium carbonate content of soil was the only soil property that significantly contributed to predicting when liquid P was more effective than granular P.
Five soil P test procedures (Bray, Colwell, resin, isotopically exchangeable P, and diffusive gradients in thin films (DGT)) were assessed to determine their ability to measure soil test P on subsamples of soil collected before the experiment started. These soil test values were then related to the dry matter shoot yields to assess their ability to predict wheat yield responses to P applied as liquid or granular P. All 5 soil test procedures provided a reasonable prediction of dry matter responses to applied P as either liquid or granular P, with the resin P test having a slightly greater predictive capacity on the range of soils tested.
The findings of this investigation suggest that liquid P fertilisers do have some potential applications in non-calcareous soils and confirm current recommendations for use of liquid P fertiliser to grow cereal crops in highly calcareous soils. Soil P testing procedures require local calibration for response to the P source that is going to be used to amend P deficiency.
Relationships between field texture and particle-size distribution in Australia and their implications
Authors: Minasny Budiman , McBratney Alex B. , Field Damien J. , Tranter Grant , McKenzie Neil J. , Brough Daniel M.
Published: September 2007

This paper aims to establish the means and ranges of clay, silt, and sand contents from field texture classes, and to investigate the differences in the field texture classes and texture determined from particle-size analysis. The results of this paper have 2 practical applications: (1) to estimate the particle size distribution and its uncertainty from field texture as input to pedotransfer functions, and (2) to examine the criteria of texture contrast soils in the Australian Soil Classification system. Estimates of clay, silt, and sand content for each field texture class are given and this allows the field texture classes to be plotted in the texture triangle. There are considerable differences between field texture classes and particle-size classes. Based on the uncertainties in determining the clay content from field texture, we establish the probability of the occurrence of a texture contrast soil according to the Australian Soil Classification system, given the texture of the B2 horizon and its overlying A horizon. I enjoy doing the soil-texture feel test with my fingers or kneading a clay soil, which is a short step from ceramics or sculpture. Hans Jenny (1984)
Targeting thyroid hormone receptor-β agonists to the liver reduces cholesterol and triglycerides and improves the therapeutic index
Authors: Erion Mark D. , Cable Edward E. , Ito Bruce R. , Jiang Hongjian , Fujitaki James M. , Finn Patricia D. , Zhang Bao-Hong , Hou Jinzhao , Boyer Serge H. , van Poelje Paul D. , Linemeyer David L.
Published: September 2007

Despite efforts spanning four decades, the therapeutic potential of thyroid hormone receptor (TR) agonists as lipid-lowering and anti-obesity agents remains largely unexplored in humans because of dose-limiting cardiac effects and effects on the thyroid hormone axis (THA), muscle metabolism, and bone turnover. TR agonists selective for the TRβ isoform exhibit modest cardiac sparing in rodents and primates but are unable to lower lipids without inducing TRβ-mediated suppression of the THA. Herein, we describe a cytochrome P450-activated prodrug of a phosphonate-containing TR agonist that exhibits increased TR activation in the liver relative to extrahepatic tissues and an improved therapeutic index. Pharmacokinetic studies in rats demonstrated that the prodrug (2
R
,4
S
)-4-(3-chlorophenyl)-2-[(3,5-dimethyl-4-(4′-hydroxy-3′-isopropylbenzyl)phenoxy)methyl]-2-oxido-[1,3,2]-dioxaphosphonane (MB07811) undergoes first-pass hepatic extraction and that cleavage of the prodrug generates the negatively charged TR agonist (3,5-dimethyl-4-(4′-hydroxy-3′-isopropylbenzyl)phenoxy)methylphosphonic acid (MB07344), which distributes poorly into most tissues and is rapidly eliminated in the bile. Enhanced liver targeting was further demonstrated by comparing the effects of MB07811 with 3,5,3′-triiodo-
l
-thyronine (T
3
) and a non-liver-targeted TR agonist, 3,5-dichloro-4-(4-hydroxy-3-isopropylphenoxy)phenylacetic acid (KB-141) on the expression of TR agonist-responsive genes in the liver and six extrahepatic tissues. The pharmacologic effects of liver targeting were evident in the normal rat, where MB07811 exhibited increased cardiac sparing, and in the diet-induced obese mouse, where, unlike KB-141, MB07811 reduced cholesterol and both serum and hepatic triglycerides at doses devoid of effects on body weight, glycemia, and the THA. These results indicate that targeting TR agonists to the liver has the potential to lower both cholesterol and triglyceride levels with an acceptable safety profile.
Simulating replica exchange simulations of protein folding with a kinetic network model
Authors: Zheng Weihua , Andrec Michael , Gallicchio Emilio , Levy Ronald M.
Published: September 2007

Replica exchange (RE) is a generalized ensemble simulation method for accelerating the exploration of free-energy landscapes, which define many challenging problems in computational biophysics, including protein folding and binding. Although temperature RE (T-RE) is a parallel simulation technique whose implementation is relatively straightforward, kinetics and the approach to equilibrium in the T-RE ensemble are very complicated; there is much to learn about how to best employ T-RE to protein folding and binding problems. We have constructed a kinetic network model for RE studies of protein folding and used this reduced model to carry out “simulations of simulations” to analyze how the underlying temperature dependence of the conformational kinetics and the basic parameters of RE (e.g., the number of replicas, the RE rate, and the temperature spacing) all interact to affect the number of folding transitions observed. When protein folding follows anti-Arrhenius kinetics, we observe a speed limit for the number of folding transitions observed at the low temperature of interest, which depends on the maximum of the harmonic mean of the folding and unfolding transition rates at high temperature. The results shown here for the network RE model suggest ways to improve atomic-level RE simulations such as the use of “training” simulations to explore some aspects of the temperature dependence for folding of the atomic-level models before performing RE studies.
Pathogenic mechanism of a human mitochondrial tRNA
Phe
mutation associated with myoclonic epilepsy with ragged red fibers syndrome
Authors: Ling Jiqiang , Roy Hervé , Qin Daoming , Rubio Mary Anne T. , Alfonzo Juan D. , Fredrick Kurt , Ibba Michael
Published: September 2007

Human mitochondrial tRNA (hmt-tRNA) mutations are associated with a variety of diseases including mitochondrial myopathies, diabetes, encephalopathies, and deafness. Because the current understanding of the precise molecular mechanisms of these mutations is limited, there is no efficient method to treat their associated mitochondrial diseases. Here, we use a variety of known mutations in hmt-tRNA
Phe
to investigate the mechanisms that lead to malfunctions. We tested the impact of hmt-tRNA
Phe
mutations on aminoacylation, structure, and translation elongation-factor binding. The majority of the mutants were pleiotropic, exhibiting defects in aminoacylation, global structure, and elongation-factor binding. One notable exception was the G34A anticodon mutation of hmt-tRNA
Phe
(mitochondrial DNA mutation G611A), which is associated with MERRF (myoclonic epilepsy with ragged red fibers).
In vitro
, the G34A mutation decreases aminoacylation activity by 100-fold, but does not affect global folding or recognition by elongation factor. Furthermore, G34A hmt-tRNA
Phe
does not undergo adenosine-to-inosine (A-to-I) editing, ruling out miscoding as a possible mechanism for mitochondrial malfunction. To improve the aminoacylation state of the mutant tRNA, we modified the tRNA binding domain of the nucleus-encoded human mitochondrial phenylalanyl-tRNA synthetase, which aminoacylates hmt-tRNA
Phe
with cognate phenylalanine. This variant enzyme displayed significantly improved aminoacylation efficiency for the G34A mutant, suggesting a general strategy to treat certain classes of mitochondrial diseases by modification of the corresponding nuclear gene.
Anatomy of energetic changes accompanying urea-induced protein denaturation
Authors: Auton Matthew , Holthauzen Luis Marcelo F. , Bolen D. Wayne
Published: September 2007

Because of its protein-denaturing ability, urea has played a pivotal role in the experimental and conceptual understanding of protein folding and unfolding. The measure of urea's ability to force a protein to unfold is given by the
m
value, an experimental quantity giving the free energy change for unfolding per molar urea. With the aid of Tanford's transfer model [Tanford C (1964)
J Am Chem Soc
86:2050–2059], we use newly obtained group transfer free energies (GTFEs) of protein side-chain and backbone units from water to 1 M urea to account for the
m
value of urea, and the method reveals the anatomy of protein denaturation in terms of residue-level free energy contributions of groups newly exposed on denaturation. The GTFEs were obtained by accounting for solubility and activity coefficient ratios accompanying the transfer of glycine from water to 1 M urea. Contrary to the opinions of some researchers, the GTFEs show that urea does not denature proteins through favorable interactions with nonpolar side chains; what drives urea-induced protein unfolding is the large favorable interaction of urea with the peptide backbone. Although the
m
value is said to be proportional to surface area newly exposed on denaturation, only ≈25% of the area favorably contributes to unfolding (because of newly exposed backbone units), with ≈75% modestly opposing urea-induced denaturation (originating from side-chain exposure). Use of the transfer model and newly determined GTFEs achieves the long-sought goal of predicting urea-dependent cooperative protein unfolding energetics at the level of individual amino acid residues.
Organization of cellulose synthase complexes involved in primary cell wall synthesis in
Arabidopsis thaliana
Authors: Desprez Thierry , Juraniec Michal , Crowell Elizabeth Faris , Jouy Hélène , Pochylova Zaneta , Parcy Francois , Höfte Herman , Gonneau Martine , Vernhettes Samantha
Published: September 2007

In all land plants, cellulose is synthesized from hexameric plasma membrane complexes. Indirect evidence suggests that in vascular plants the complexes involved in primary wall synthesis contain three distinct cellulose synthase catalytic subunits (CESAs). In this study, we show that CESA3 and CESA6 fused to GFP are expressed in the same cells and at the same time in the hypocotyl of etiolated seedlings and migrate with comparable velocities along linear trajectories at the cell surface. We also show that CESA3 and CESA6 can be coimmunoprecipitated from detergent-solubilized extracts, their protein levels decrease in mutants for either
CESA3
,
CESA6
, or
CESA1
and CESA3, CESA6 and also CESA1 can physically interact
in vivo
as shown by bimolecular fluorescence complementation. We also demonstrate that CESA6-related CESA5 and CESA2 are partially, but not completely, redundant with CESA6 and most likely compete with CESA6 for the same position in the cellulose synthesis complex. Using promoter-β-glucuronidase fusions we show that
CESA5
,
CESA6
, and
CESA2
have distinct overlapping expression patterns in hypocotyl and root corresponding to different stages of cellular development. Together, these data provide evidence for the existence of binding sites for three distinct CESA subunits in primary wall cellulose synthase complexes, with two positions being invariably occupied by CESA1 and CESA3, whereas at least three isoforms compete for the third position. Participation of the latter three isoforms might fine-tune the CESA complexes for the deposition of microfibrils at distinct cellular growth stages.
Genetic evidence for three unique components in primary cell-wall cellulose synthase complexes in
Arabidopsis
Authors: Persson Staffan , Paredez Alexander , Carroll Andrew , Palsdottir Hildur , Doblin Monika , Poindexter Patricia , Khitrov Natalie , Auer Manfred , Somerville Chris R.
Published: September 2007

In higher plants, cellulose is synthesized at the plasma membrane by the cellulose synthase (CESA) complex. The catalytic core of the complex is believed to be composed of three types of CESA subunits. Indirect evidence suggests that the complex associated with primary wall cellulose deposition consists of CESA1, -3, and -6 in
Arabidopsis thaliana
. However, phenotypes associated with mutations in two of these genes,
CESA1
and
-6
, suggest unequal contribution by the different CESAs to overall enzymatic activity of the complex. We present evidence that the primary complex requires three unique types of components, CESA1-, CESA3-, and CESA6-related, for activity. Removal of any of these components results in gametophytic lethality due to pollen defects, demonstrating that primary-wall cellulose synthesis is necessary for pollen development. We also show that the CESA6-related CESAs are partially functionally redundant.
Structural insight into Ca
2+
specificity in tetrameric cation channels
Authors: Alam Amer , Shi Ning , Jiang Youxing
Published: September 2007

Apparent blockage of monovalent cation currents by the permeating blocker Ca
2+
is a physiologically essential phenomenon relevant to cyclic nucleotide-gated (CNG) channels. The recently determined crystal structure of a bacterial homolog of CNG channel pores, the NaK channel, revealed a Ca
2+
binding site at the extracellular entrance to the selectivity filter. This site is not formed by the side-chain carboxylate groups from the conserved acidic residue, Asp-66 in NaK, conventionally thought to directly chelate Ca
2+
in CNG channels, but rather by the backbone carbonyl groups of residue Gly-67. Here we present a detailed structural analysis of the NaK channel with a focus on Ca
2+
permeability and blockage. Our results confirm that the Asp-66 residue, although not involved in direct chelation of Ca
2+
, plays an essential role in external Ca
2+
binding. Furthermore, we give evidence for the presence of a second Ca
2+
binding site within the NaK selectivity filter where monovalent cations also bind, providing a structural basis for Ca
2+
permeation through the NaK pore. Compared with other Ca
2+
-binding proteins, both sites in NaK present a novel mode of Ca
2+
chelation, using only backbone carbonyl oxygen atoms from residues in the selectivity filter. The external site is under indirect control by an acidic residue (Asp-66), making it Ca
2+
-specific. These findings give us a glimpse of the possible underlying mechanisms allowing Ca
2+
to act both as a permeating ion and blocker of CNG channels and raise the possibility of a similar chemistry governing Ca
2+
chelation in Ca
2+
channels.
A continuum whose hyperspace of subcontinua is not its continuous image
Authors: Illanes Alejandro
Published: September 2007

We construct a metric continuum

X
X

such that the hyperspace of subcontinua,

C
(
X
)

C(X)

, of

X
X

is not a continuous image of

X
X

. This answers a question by I. Krzemińska and J. R. Prajs.
Represented value sets for integral binary quadratic forms and lattices
Authors: Earnest A. , Fitzgerald Robert
Published: September 2007

A characterization is given for the integral binary quadratic forms for which the set of represented values is closed under products. It is also proved that for an integral binary quadratic lattice over a Dedekind domain, the product of three values represented by the form is again a value represented by the form. This generalizes the trigroup property observed by V. Arnold in the case of integral binary quadratic forms.
On the index and spectrum of differential operators on ℝ^{ℕ}
Authors: Rabier Patrick
Published: September 2007

IfP(x,∂)P(x,\partial )is anr×rr\times rsystem of differential operators onRN\mathbb {R}^{N}having continuous coefficients with vanishing oscillation at infinity, the Cordes–Illner theory ensures thatP(x,∂)P(x,\partial )is Fredholm from(Wm,p)r(W^{m,p})^{r}to(Lp)r(L^{p})^{r}for all or no valuep∈(1,∞).p\in (1,\infty ).We prove that both the index (when defined) and the spectrum ofP(x,∂)P(x,\partial )are independent ofp.p.
Periodic homotopy and conjugacy idempotents
Authors: Smrekar Jaka
Published: September 2007

A self-map

f
f

on the CW complex

Z
Z

is a periodic homotopy idempotent if for some

r
⩾
0

r\geqslant 0

and

p
>
0

p>0

the iterates

f
r

f^r

and

f

r
+
p

f^{r+p}

are homotopic. Geoghegan and Nicas defined the rotation index

R
I
(
f
)

RI(f)

of such a map. They proved that for

r
=
p
=
1

r=p=1

, the homotopy idempotent

f
f

splits if and only if

R
I
(
f
)
=
1

RI(f)=1

, while for

r
=
0

r=0

, the index

R
I
(
f
)

RI(f)

divides

p
2

p^2

. We extend this to arbitrary

p
p

and

r
r

, and generalize various results related to the splitting of homotopy idempotents on CW complexes and conjugacy idempotents on groups.
On positive unipotent operators on Banach lattices
Authors: Drnovšek Roman
Published: September 2007

Let

T
T

be a positive operator on a complex Banach lattice. We prove that

T
T

is greater than or equal to the identity operator

I
I

if
\[

lim

n
→
∞

n

‖
(
T
−
I

)
n

‖

1

/

n

=
0.

\lim _{n \rightarrow \infty } n \, \|(T - I)^n\|^{1/n} = 0.

\]
A Computer Proof of Moll’s Log-Concavity Conjecture
Authors: Kauers Manuel , Paule Peter
Published: September 2007

In a study on quartic integrals, Moll met a specialized family of Jacobi polynomials. He conjectured that the corresponding coefficient sequences are log-concave. In this paper we settle Moll’s conjecture by a nontrivial usage of computer algebra.
Spectral flow as winding number and integral formulas
Authors: Wahl Charlotte
Published: September 2007

A general integral formula for the spectral flow of a path of unbounded selfadjoint Fredholm operators subject to certain summability conditions is derived from the interpretation of the spectral flow as a winding number.
On weighted 𝐿² cohomology
Authors: Miller John
Published: September 2007

Consider an orientable manifold with countably many complete components of bounded dimension. Suppose that its rational homology is infinitely generated in some degree. Then there is no choice of weight function for which the natural map from weighted

L

2

L^{2}

cohomology to de Rham cohomology is surjective in that degree.
Chebotarev-type theorems in homology classes
Authors: Pollicott Mark , Sharp Richard
Published: September 2007

We describe how closed geodesics lying in a prescribed homology class on a negatively curved manifold split when lifted to a finite cover. This generalizes a result of Zelditch in the case of compact hyperbolic surfaces.
Metric entropy of high dimensional distributions
Authors: Blei Ron , Gao Fuchang , Li Wenbo
Published: September 2007

Let

F

d

\mathcal F_d

be the collection of all

d
d

-dimensional probability distribution functions on

[
0
,
1

]
d

[0,1]^d

,

d
≥
2

d\ge 2

. The metric entropy of

F

d

\mathcal F_d

under the

L
2

(
[
0
,
1

]
d

)

L_2([0,1]^d)

norm is studied. The exact rate is obtained for

d
=
1
,
2

d=1,2

and bounds are given for

d
>
3

d>3

. Connections with small deviation probability for Brownian sheets under the sup-norm are established.
The Kac Jordan superalgebra: automorphisms and maximal subalgebras
Authors: Elduque Alberto , Laliena Jesús , Sacristán Sara
Published: September 2007

In this note the group of automorphisms of the Kac Jordan superalgebra is described and used to classify the maximal subalgebras.
Homogeneous polynomials on strictly convex domains
Authors: Kot Piotr
Published: September 2007

We consider a circular, bounded, strictly convex domain

Ω
⊂

C

d

\Omega \subset \mathbb C^{d}

with boundary of class

C

2

C^{2}

. For any compact subset

K
K

of

∂
Ω

\partial \Omega

we construct a sequence of homogeneous polynomials on

Ω
\Omega

which are big at each point of

K
K

. As an application for any

E
⊂
∂
Ω

E\subset \partial \Omega

circular subset of type

G

δ

G_{\delta }

we construct a holomorphic function

f
f

which is square integrable on

Ω
∖

D

E

\Omega \setminus \mathbb DE

and such that
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper E equals upper E Subscript normal upper Omega Superscript 2 Baseline left-parenthesis f right-parenthesis colon equals StartSet z element-of partial-differential normal upper Omega colon integral Underscript double-struck upper D z Endscripts StartAbsoluteValue f EndAbsoluteValue squared d German upper L Subscript double-struck upper D z Superscript 2 Baseline equals normal infinity EndSet">

E
=

E

Ω

2

(
f
)
:=

{
z
∈
∂
Ω
:

∫

D

z

|
f
|

2

d

L

D

z

2

=
∞
}

E=E_{\Omega }^{2}(f):=\left \{z\in \partial \Omega : \int _{\mathbb Dz}\left |f\right |^{2}d\mathfrak {L}_{\mathbb Dz}^{2} =\infty \right \}

where

D

\mathbb D

denotes unit disc in

C

\mathbb C

.
Solutions for a nonlocal conservation law with fading memory
Authors: Chen Gui-Qiang , Christoforou Cleopatra
Published: September 2007

Global entropy solutions in

B
V

BV

for a scalar nonlocal conservation law with fading memory are constructed as the limits of vanishing viscosity approximate solutions. The uniqueness and stability of entropy solutions in

B
V

BV

are established, which also yield the existence of entropy solutions in

L
∞

L^\infty

while the initial data is only in

L
∞

L^\infty

. Moreover, if the memory kernel depends on a relaxation parameter

ε
>
0

\varepsilon >0

and tends to a delta measure weakly as measures when

ε
→
0
+

\varepsilon \to 0+

, then the global entropy solution sequence in

B
V

BV

converges to an admissible solution in

B
V

BV

for the corresponding local conservation law.
Examples of Fano varieties of index one that are not birationally rigid
Authors: Castravet Ana-Maria
Published: September 2007

A conjecture of Pukhlikov states that a smooth Fano variety of dimension at least 4 and index one is birationally rigid. We show that a general member of the linear system given by the ample generator of the Picard group of the moduli space of stable, rank 2 bundles with fixed determinant of odd degree on a curve of genus at least 3 is not birationally rigid.
Extremal pseudocompact Abelian groups are compact metrizable
Authors: Comfort W. , van Mill Jan
Published: September 2007

Every pseudocompact Abelian group of uncountable weight has both a proper dense pseudocompact subgroup and a strictly finer pseudocompact group topology.
Maximality of sums of two maximal monotone operators in general Banach space
Authors: Borwein, FRSC Jonathan
Published: September 2007

We combine methods from convex analysis, based on a function of Simon Fitzpatrick, with a fine recent idea due to Voisei, to prove maximality of the sum of two maximal monotone operators in Banach space under various natural domain and transversality conditions.
On the critical points of the 𝐸_{𝑘} functionals in Kähler geometry
Authors: Tosatti Valentino
Published: September 2007

We prove that a Kähler metric in the anticanonical class, that is a critical point of the functional

E
k

E_k

and has nonnegative Ricci curvature, is necessarily Kähler-Einstein. This partially answers a question of X.X. Chen.
On quasi-isometric embeddings of Lamplighter groups
Authors: Inamdar S. , Naolekar Aniruddha
Published: September 2007

We denote by

Γ
G

\Gamma _G

the Lamplighter group of a finite group

G
G

. In this article, we show that if

G
G

and

H
H

are two finite groups with at least two elements, then there exists a quasi-isometric embedding from

Γ
G

\Gamma _G

to

Γ
H

\Gamma _H

. We also prove that the quasi-isometry group

Q

I
(

Γ
G

)

{\mathcal Q}I(\Gamma _G)

of

Γ
G

\Gamma _G

contains all finite groups. We then show that the group of automorphisms of

Γ

Z

n

\Gamma _{{\mathbb Z}_n}

has infinite index in

Q

I
(

Γ

Z

n

)

{\mathcal Q}I(\Gamma _{{\mathbb Z}_n})

.
On the topology of the boundary of a basin of attraction
Authors: Sánchez-Gabites J. , Sanjurjo J.
Published: September 2007

Suppose

φ
:
M
×

R

⟶
M

\varphi : M \times \mathbb {R} \longrightarrow M

is a continuous flow on a locally compact metrizable space

M
M

and

K
K

is an (asymptotically stable) attractor. Let

D
=
∂

A

(
K
)

D = \partial \mathcal {A}(K)

be the boundary of the basin of attraction of

K
K

. In the present paper it will be shown how the Conley index of

D
D

plays an important role in determining the topological nature of

D
D

and allows one to obtain information about the global dynamics of

φ
\varphi

in

M
M

.
Global existence of solutions to Shigesada-Kawasaki-Teramoto cross-diffusion systems on domains of arbitrary dimensions
Authors: Tuộc Phan
Published: September 2007

We consider a strongly coupled nonlinear parabolic system which arises in population dynamics in

n
n

-dimensional domains (

n
≥
1

n\geq 1

). Global existence of classical solutions under certain restrictions on the coefficients is established.
The complete isomorphism class of an operator space
Authors: Oikhberg Timur
Published: September 2007

Suppose

X
X

is an infinite-dimensional operator space and

n
n

is a positive integer. We prove that for every

C
>
0

C > 0

there exists an operator space

X
~

\tilde {X}

such that the formal identity map

i
d
:
X
→

X
~

id : X \to \tilde {X}

is a complete isomorphism,

I

M

n

⊗
i
d

I_{\mathbf {M}_n} \otimes id

is an isometry, and

d

c
b

(
X
,

X
~

)
>
C

d_{cb}(X, \tilde {X}) > C

. This provides a non-commutative counterpart to a recent result of W. Johnson and E. Odell.
Separating classes of composition operators via subnormal condition
Authors: Jung Il , Lee Mi , Park Sang
Published: September 2007

Several classes have been considered to study the weak subnormalities of Hilbert space operators. One of them is

n
n

-hypnormality, which comes from the Bram-Halmos criterion for subnormal operators. In this note we consider

E
(
n
)

E(n)

-hyponormality, which is the parallel version corresponding to the Embry characterization for subnormal operators. We characterize

E
(
n
)

E(n)

-hyponormality of composition operators via

k
k

-th Radon-Nikodym derivatives and present some examples to distinguish the classes.
On support varieties for modules over complete intersections
Authors: Bergh Petter
Published: September 2007

Let

(
A
,

m

,
k
)

(A, \mathfrak {m}, k)

be a complete intersection of codimension

c
c

, and let

k
~

\tilde {k}

be the algebraic closure of

k
k

. We show that every homogeneous algebraic subset of

k
~

c

\tilde {k}^c

is the cohomological support variety of an

A
A

-module, and that the projective variety of a complete indecomposable maximal Cohen–Macaulay

A
A

-module is connected.
Compact quantum group actions on C*-algebras and invariant derivations
Authors: Dumitru Raluca , Peligrad Costel
Published: September 2007

We define the notion of invariant derivation of a C*-algebra under a compact quantum group action and prove that in certain conditions, such derivations are generators of one parameter automorphism groups.
Stability and exact multiplicity of periodic solutions of Duffing equations with cubic nonlinearities
Authors: Chen Hongbin , Li Yi
Published: September 2007

We study the stability and exact multiplicity of periodic solutions of the Duffing equation with cubic nonlinearities,

(

∗

)

x
+
c

x
′

+
a
x
−

x

3

=
h
(
t
)
,

\begin{equation*} x+cx’+ax-x^{3}=h(t),\tag {$*$} \end{equation*}

where

a
a

and

c
>
0

c>0

are positive constants and

h
(
t
)

h(t)

is a positive

T
T

-periodic function. We obtain sharp bounds for

h
h

such that

(
∗
)

(*)

has exactly three ordered

T
T

-periodic solutions. Moreover, when

h
h

is within these bounds, one of the three solutions is negative, while the other two are positive. The middle solution is asymptotically stable, and the remaining two are unstable.
Measures on independent sets, a quantitative version of Rudin’s theorem
Authors: Körner T.
Published: September 2007

We construct measures with independent support whose Fourier coefficients decrease as fast as possible.
Sums of entire functions having only real zeros
Authors: Adams Steven , Cardon David
Published: September 2007

We show that certain sums of products of Hermite-Biehler entire functions have only real zeros, extending results of Cardon. As applications of this theorem, we construct sums of exponential functions having only real zeros, we construct polynomials having zeros only on the unit circle, and we obtain the three-term recurrence relation for an arbitrary family of real orthogonal polynomials. We discuss a similarity of this result with the Lee-Yang Circle Theorem from statistical mechanics. Also, we state several open problems.
Neumann boundary conditions for a nonlocal nonlinear diffusion operator. Continuous and discrete models
Authors: Bogoya Mauricio , Ferreira Raul , Rossi Julio
Published: September 2007

Let

J
:

R

→

R

J: \mathbb {R} \to \mathbb {R}

be a nonnegative, smooth function with

∫

R

J
(
r
)
d
r
=
1

\int _{\mathbb {R}} J(r)dr =1

, supported in

[
−
1
,
1
]

[-1,1]

, symmetric,

J
(
r
)
=
J
(
−
r
)

J(r)=J(-r)

, and strictly increasing in

[
−
1
,
0
]

[-1,0]

. We consider the Neumann boundary value problem for a nonlocal, nonlinear operator that is similar to the porous medium, and we study the equation
\[
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="u Subscript t Baseline left-parenthesis x comma t right-parenthesis equals integral Subscript negative upper L Superscript upper L Baseline left-parenthesis upper J left-parenthesis StartFraction x minus y Over u left-parenthesis y comma t right-parenthesis EndFraction right-parenthesis minus upper J left-parenthesis StartFraction x minus y Over u left-parenthesis x comma t right-parenthesis EndFraction right-parenthesis right-parenthesis d y comma x element-of left-bracket negative upper L comma upper L right-bracket period">

u
t

(
x
,
t
)
=

∫

−
L

L

(
J

(

x
−
y

u
(
y
,
t
)

)

−
J

(

x
−
y

u
(
x
,
t
)

)

)

d
y
,

x
∈
[
−
L
,
L
]
.

\displaystyle u_t (x,t)= \int _{-L}^{L} \left (J\left (\dfrac {x-y}{u(y,t)}\right ) - J\left (\dfrac {x-y}{u(x,t)}\right ) \right ) \, dy, \quad x \in [-L,L].

\]
We prove existence and uniqueness of solutions and a comparison principle. We find the asymptotic behaviour of the solutions as

t
→
∞

t\to \infty

: they converge to the mean value of the initial data. Next, we consider a discrete version of the above problem. Under suitable hypotheses we prove that the discrete model has properties analogous to the continuous one. Moreover, solutions of the discrete problem converge to the continuous ones when the mesh parameter goes to zero. Finally, we perform some numerical experiments.
Degree one maps between hyperbolic small 3-manifolds
Authors: Boileau Michel , Wang Shicheng
Published: September 2007

We construct the first examples of degree one maps between non-homeomorphic closed hyperbolic small 3-manifolds.
Late Endosomal Traffic of the Epidermal Growth Factor Receptor Ensures Spatial and Temporal Fidelity of Mitogen-activated Protein Kinase Signaling
Authors: Taub N. , Teis D. , Ebner H. L. , Hess M. W. , Huber L. A.
Published: September 2007

Mitogen-activated protein kinase (MAPK) signaling is regulated by assembling distinct scaffold complexes at the plasma membrane and on endosomes. Thus, spatial resolution might be critical to determine signaling specificity. Therefore, we investigated whether epidermal growth factor receptor (EGFR) traffic through the endosomal system provides spatial information for MAPK signaling. To mislocalize late endosomes to the cell periphery we used the dynein subunit p50 dynamitin. The peripheral translocation of late endosomes resulted in a prolonged EGFR activation on late endosomes and a slow down in EGFR degradation. Continuous EGFR signaling from late endosomes caused sustained extracellular signal-regulated kinase and p38 signaling and resulted in hyperactivation of nuclear targets, such as Elk-1. In contrast, clustering late endosomes in the perinuclear region by expression of dominant active Rab7 delayed the entry of the EGFR into late endosomes, which caused a delay in EGFR degradation and a sustained MAPK signaling. Surprisingly, the activation of nuclear targets was reduced. Thus, we conclude that appropriate trafficking of the activated EGFR through endosomes controls the spatial and temporal regulation of MAPK signaling.
9 Ovid's Liberalia
Authors: Miller John F.
Published: September 2007

This chapter offers an explication of the feast in honour of Liber (F. 3. 713-90) in the light of a) the interplay of Greek myth and Roman cult; b) the mixing of presentational modes (didactic, hymnic, narrative, aetiological); c) generic self-consciousness (how Ovid meets the challenge of narrative in the elegiac meter); d) how Ovid imagines the details of the festival against the background of what we know of the Liberalia from elsewhere (the inscribed calendars, Varro, Macrobius, Augustine, and others).
10 Contesting Time and Space:Fasti6. 637–48
Authors: Newlands Carole E.
Published: September 2007

This chapter reads in the anecdote of Vedius Pollio’s house (F. 6. 637-48) four overlapping themes: an appropriate conclusion to a day that begins in pre-Roman Italy, moves to the regal period, and ends in the Augustan present; a dramatic reification of Augustus’ attempt to give June 11 new meaning as a day honouring his wife and imperial family; the beginning of a moralizing tradition of the harmfulness of luxury and true authority of fine leadership, evident later in Dio and Seneca; and a shifting resignification of the site from the palace of Servius Tullius to Vedius’ Pollio’s house to Livia’s Porticus, vivid illustration of the way in which Augustus redrew the map of Rome.
11 Added Days: Calendrical Poetics and the Julio‐Claudian Holidays
Authors: Pasco-Pranger M.
Published: September 2007

This chapter selects Fasti 1.461-722 as evidence for the impact of the calendrical structure both on the intentional placement of new holidays by the principes, and on historical reinterpretations of the meanings of these holidays. It argues that the new holidays, far from being fixed and so distinguishable from the flexible, exegetical situations in the older calendrical material, are, in a calendrical context, equally open to poetic connections, integration with the surrounding days, expansion, and revision. The new Julio-Claudian festivals, in other words, ‘make meaning’ beyond their prescribed commemorative function through a dynamic use of connections encouraged by the existing calendrical structure. Ovid’s poem on the one hand seems to follow the princeps’ guiding hand, but also demonstrates the impossibility of his fully controlling the meanings built by readers of the calendar.
12 Ovid and the Stage
Authors: Wiseman T. P.
Published: September 2007

Careful investigation of the contemporary evidence (mainly Cicero) suggests that mime was a major part of the theatrical repertory at the Roman games in the first century BC, and that mythological burlesque was one of its regular themes. With this in mind, and building on the one piece of direct evidence (Fasti 4.326), it is possible to reconstruct hypothetical stage originals for various episodes in both the Fasti and the Metamorphoses.
Passion's Triumph over Reason
Authors: Tilmouth Christopher
Published: September 2007

This book surveys ideas of passion, reason, appetite, and self-control in English literature and moral thought from 1580 to 1680. Drawing on tragedy, poetry, moral philosophy, and sermons, the book explores how Renaissance writers transformed their understanding of the passions, re-evaluating emotion so as to make it an important constituent of ethical life rather than the enemy within which allegory had traditionally cast it as being. Part One of the book describes various ethical positions available to early modern readers, including those of Erasmus, the Stoics, and Calvin. It then explores the role of psychomachia and a hostility to the passions in Spenser's Faerie Queene, before turning to plays by Shakespeare and Chapman (Hamlet, Julius Caesar, Troilus and Cressida, Bussy D'Ambois) which challenge the moral assumptions, and particularly the antipathy towards the emotions, prevalent in late Elizabethan England. It also examines the impact which Augustinianism and Aristotelianism had on the poetry of Herbert, Crashaw, and Milton. These latter traditions are shown to promote a positive evaluation of emotion when that emotion is inflected either by God's grace or by a principle of rational moderation. Part Two of the book traces the rise and fall of Restoration libertinism, particularly under the influence of Hobbes's philosophy and French libertinism. This tradition, which celebrated passion and appetite as natural, and accorded them free expression, is traced in works by Etherege, Dryden, and the Earl of Rochester. It is argued that such libertinism ultimately proved dissatisfying even on its own terms.
Positions in Early Modern Moral Thought
Authors: Tilmouth Christopher
Published: September 2007

This chapter describes ideas of rational self-governance and assessments of the worth (or otherwise) of the passions put forward by: Erasmus and Plato; Cicero and the Stoics; Aristotle, Aquinas, and other Aristotelian writers; and Calvin and selected English Calvinists. The Platonists and Stoics are shown to be hostile to the passions, advocating psychomachia, i.e., a rational struggle against such emotions. By contrast, some of the Aristotelians — those whose thinking on the affections is scarcely taken up in Elizabethan England — think the latter can be habituated under reason's influence so as to assist virtue's purposes. Calvinists dismiss human nature (and hence also the passions) as utterly depraved and incapable of goodness except when visited by God's grace. Even when such grace is bestowed, this does not wholly redeem man's felt life.
Hobbes: Fear, Power, and the Passions
Authors: Tilmouth Christopher
Published: September 2007

This chapter presents Hobbes as a philosopher who overturned prevailing assumptions about the passions, abandoning, in particular, the ideals on which psychomachia was based. Hobbes casts the passions as natural and thus proper determinants of behaviour, measures of self-interest which (rather than eschewing) man should rightfully embrace. These passions are related to a kinetic idea of happiness, the precept that felicity consists in a constant motion from one appetite to the next. Hobbes conceives of reason, not as a transcendent faculty, policing actions in the light of absolute moral principles, but as an instrumental faculty, the function of which is to optimize the fulfilment of as many appetites as possible. The alleviation of fear of others' random aggression is critical to this process, which is why instrumental reason advocates the creation of a civil society headed by a sovereign so terrifying that none will disobey his laws.
5 Church Established
Authors: BRUCE STEVE
Published: September 2007

This chapter details the growth of the Free Presbyterian Church of Ulster in Northern Ireland (and its international expansion) and its development of schools, missionary work, and theological training. It considers whether success and increasing public acceptance has moderated the Church's distinctive separatism and its puritanism, and concludes that growth has not resulted in much change yet.
8 With God on his Side
Authors: Bruce Steve
Published: September 2007

This final chapter considers the part that religion has played in Paisley's politics and his political appeal. It argues that Paisley's religious identity was an important part of his political appeal to a minority of unionist voters. While securing his core support, his constant criticisms of liberal and ecumenical deviations in the major Protestant churches alienated many unionists. However, between 2000 and 2005, unionist frustration with the political changes forced by the British Government led enough of those unionists to set aside their dislike for Paisley, and to place the future of Ulster unionism in the hands of the DUP.
The DOMON domains are involved in heme and sugar recognition
Authors: Iyer Lakshminarayan M. , Anantharaman Vivek , Aravind L.
Published: September 2007

We expand the functionally uncharacterized DOMON domain superfamily to identify several novel families, including the first prokaryotic representatives. Using several computational tools we show that it is involved in ligand binding—either as heme- or sugar-binding domains. We present evidence that the DOMON domain along with the DM13 domain comprises a novel electron-transfer system potentially involved in oxidative modification of animal cell-surface proteins. Other novel versions might function as sugar sensors of histidine kinases of bacterial two component systems.

Contact:  aravind@ncbi.nlm.nih.gov or aravind@mail.nih.gov

Supplementary information: Supplementary data are available at Bioinformatics online and also at ftp://ftp.ncbi.nih.gov/pub/aravind/domon/.
A parsimonious threshold-independent protein feature selection method through the area under receiver operating characteristic curve
Authors: Wang Zhanfeng , Chang Yuan-chin I. , Ying Zhiliang , Zhu Liang , Yang Yaning
Published: September 2007

Motivation: Protein expression profiling for differences indicative of early cancer holds promise for improving diagnostics. Due to their high dimensionality, statistical analysis of proteomic data from mass spectrometers is challenging in many aspects such as dimension reduction, feature subset selection as well as construction of classification rules. Search of an optimal feature subset, commonly known as the feature subset selection (FSS) problem, is an important step towards disease classification/diagnostics with biomarkers.

Methods: We develop a parsimonious threshold-independent feature selection (PTIFS) method based on the concept of area under the curve (AUC) of the receiver operating characteristic (ROC). To reduce computational complexity to a manageable level, we use a sigmoid approximation to the empirical AUC as the criterion function. Starting from an anchor feature, the PTIFS method selects a feature subset through an iterative updating algorithm. Highly correlated features that have similar discriminating power are precluded from being selected simultaneously. The classification rule is then determined from the resulting feature subset.

Results: The performance of the proposed approach is investigated by extensive simulation studies, and by applying the method to two mass spectrometry data sets of prostate cancer and of liver cancer. We compare the new approach with the threshold gradient descent regularization (TGDR) method. The results show that our method can achieve comparable performance to that of the TGDR method in terms of disease classification, but with fewer features selected.

Availability: Supplementary Material and the PTIFS implementations are available at http://staff.ustc.edu.cn/~ynyang/PTIFS

Contact:  ynyang@ustc.edu.cn or czzhuliang@126.com

Supplementary information: Supplementary data are available at Bioinformatics online.