bluuebunny/crossref_metadata_2025_split huggingface dataset:
Can input explain children's me-for-I errors?
Authors: KIRJAVAINEN MINNA , THEAKSTON ANNA , LIEVEN ELENA 
Published: February 2009

ABSTRACTEnglish-speaking children make pronoun case errors producing utterances where accusative pronouns are used in nominative contexts (me do it). We investigate whether complex utterances in the input (Let me do it) might explain the origin of these errors. Longitudinal naturalistic data from seventeen English-speaking two- to four-year-olds was searched for 1psg accusative-for-nominative case errors and for all 1psg preverbal pronominal contexts. Their caregivers' data was also searched for 1psg preverbal pronominal contexts. The data show that the children's proportional use of me-for-I errors correlated with their caregivers' proportional use ofmein 1psg preverbal contexts. Furthermore, the verbs that children produced in me-error utterances appeared in complex sentences containingmein the input more often than verbs that did not appear in me-for-I errors in the children's speech. These findings are discussed in the context of current explanations for children's case marking errors.
Evidence for the continued existence of Abraxas Lake, Vestfold Hills, East Antarctica during the Last Glacial Maximum
Authors: Gibson John A.E. , Paterson Kristina S. , White Camille A. , Swadling Kerrie M. 
Published: February 2009

AbstractEvidence is provided from a sediment core from saline Abraxas Lake, Vestfold Hills, that indicates that the lake existed through the Last Glacial Maximum. It can therefore be concluded that at least part of the Vestfold Hills also remained ice-free through the Last Glacial Maximum, or at most was covered by a thin, non-erosive cold-based ice sheet. The evidence for the continued existence of Abraxas Lake includes a 14C date that significantly predates the Last Glacial Maximum (though this cannot be considered direct proof of the existence of the lake prior to the Last Glacial Maximum); the presence of saline porewater throughout the core, including in compacted sediments deposited during the glacial period, which implies that the lake obtained its salt prior to any Holocene marine highstand; and the occurrence of marine-derived fauna from the onset of significant biological activity late in the Pleistocene. The occurrence of ice-free land in the Vestfold Hills and similar oases suggests that the margin of the polar ice cap did not reach far beyond its current position at the Last Glacial Maximum, at least in regions now occupied by these oases.
The oocyte activation and Ca2+oscillation-inducing abilities of mouse and human dead (sonicated) spermatozoa
Authors: Yazawa Hiroyuki , Yanagida Kaoru , Hayashi Shoutaro , Sato Akira 
Published: February 2009

SummaryIn ICSI procedures, it is well known that the selection of viable (live) spermatozoa and certain types of immobilization prior to injection is very important for obtaining successful results, but unfortunately there are rare situations when only immotile spermatozoa are available (such as in severe asthenozoospermia or necrozoospermia). In such cases, failure of oocyte activation after ICSI often occurs and may be due to the lack of SOAF (sperm-borne oocyte activating factor) activity. In order to investigate the SOAF activities of dead spermatozoa, mouse and human spermatozoa were immobilized (killed by sonication), maintained in THF medium for varying time intervals (up to 72 h) and then injected into mature unfertilized mouse oocytes. Injected mouse oocytes were examined for their activation, development into blastocysts and Ca2+responses by imaging and confocal laser scanning microscope. The rates of oocyte activation, blastocyst development and normal patterns of Ca2+oscillation from the killed-sperm-injected oocytes decreased gradually in accordance with the maintenance interval between sonication and injection. For injection with mouse sonicated spermatozoa, the rate of normal Ca2+oscillations declined first (after a 3 h maintenance interval) and then blastocyst development was gradually obstructed (after approx. 10 h). The oocyte activation-inducing ability of dead spermatozoa was maintained for a relatively long period, but began to decline after 20 h. The activation rates and Ca2+response of the oocytes that were injected with human sonicated spermatozoa decreased earlier than those injected with mouse spermatozoa. Although the oocyte activation-inducing ability was maintained for a relatively long time after the death of the spermatozoa, embryo development into blastocysts and the rate of normal Ca2+oscillations declined after a short maintenance interval between sonication and injection. The Ca2+response seemed to be the most sensitive indicator for the evaluating the SOAF activity of dead (killed) spermatozoa.
Children’s and parents’ perceptions of the determinants of children’s fruit and vegetable intake in a low-intake population
Authors: Kristjansdottir Asa Gudrun , De Bourdeaudhuij Ilse , Klepp Knut-Inge , Thorsdottir Inga 
Published: February 2009

AbstractObjectiveTo study the differences between children’s self-reports and parents’ reports on environmental determinants of fruit and vegetable intake among 11-year-old children in the European country with the lowest reported consumption. A second objective was to examine the observed variance in fruit and vegetable intake among the children.DesignA cross-sectional survey was performed in Iceland as a part of the Pro Children cross-Europe survey. Children’s usual fruit and vegetable intake and its determinants were assessed through self-reports from the children (n963) and their parents’ reports.ResultsChildren reported lower availability and accessibility of fruits at home than did their parents, while the reports of children and parents for vegetables were more in agreement. A larger proportion of the observed variance in children’s fruit and vegetable intake could be explained by the child’s perception than by the parent’s perception of determinants. The strongest determinants for fruit and vegetable intake according to the children’s reports were availability at home, modelling, demanding family rule and knowledge of recommendations. The strongest modelling determinant for fruit was the father’s fruit intake while for vegetables it was eating vegetables together with the family.ConclusionEleven-year-old children should be asked themselves what determines their fruit and vegetable intake. However, children reported determinants in the physical and social environment, of which the parents are a part, as an important determinant for their intake. Interventions aiming to increase fruit and vegetable intake among children must therefore target the parents.
Spatiotemporal activation of caspase‐dependent and ‐independent pathways in staurosporine‐induced apoptosis of p53wt and p53mt human cervical carcinoma cells
Authors: Nicolier Magali , Decrion‐Barthod Anne‐Zélie , Launay Sophie , Prétet Jean‐Luc , Mougin Christiane 
Published: February 2009

Background information. Caspase‐dependent and ‐independent death mechanisms are involved in apoptosis in a variety of human carcinoma cells treated with antineoplastic compounds. Our laboratory has reported that p53 is a key contributor of mitochondrial apoptosis in cervical carcinoma cells after staurosporine exposure. However, higher mitochondrial membrane potential dissipation and greater DNA fragmentation were observed in p53wt (wild‐type p53) HeLa cells compared with p53mt (mutated p53) C‐33A cells. Here, we have studied events linked to the mitochondrial apoptotic pathway.Results. Staurosporine can induce death of HeLa cells via a cytochrome c/caspase‐9/caspase‐3 mitochondrial‐dependent apoptotic pathway and via a delayed caspase‐independent pathway. In contrast with p53wt cells, p53mt C‐33A cells exhibit firstly caspase‐8 activation leading to caspase‐3 activation and Bid cleavage followed by cytochrome c release. Attenuation of PARP‐1 [poly(ADP‐ribose) polymerase‐1] cleavage as well as oligonucleosomal DNA fragmentation in the presence of z‐VAD‐fmk points toward a major involvement of a caspase‐dependent pathway in staurosporine‐induced apoptosis in p53wt HeLa cells, which is not the case in p53mt C‐33A cells. Meanwhile, the use of 3‐aminobenzamide, a PARP‐1 inhibitor known to prevent AIF (apoptosis‐inducing factor) release, significantly decreases staurosporine‐induced death in these p53mt carcinoma cells, suggesting a preferential implication of caspase‐independent apoptosis. On the other hand, we show that p53, whose activity is modulated by pifithrin‐α, isolated as a suppressor of p53‐mediated transactivation, or by PRIMA‐1 (p53 reactivation and induction of massive apoptosis), that reactivates mutant p53, causes cytochrome c release as well as mitochondrio—nuclear AIF translocation in staurosporine‐induced apoptosis of cervical carcinoma cells.Conclusions. The present paper highlights that staurosporine engages the intrinsic mitochondrial apoptotic pathway via caspase‐8 or caspase‐9 signalling cascades and via caspase‐independent cell death, as well as through p53 activity.
New results on the least common multiple of consecutive integers
Authors: Farhi Bakir , Kane Daniel 
Published: February 2009

When studying the least common multiple of some finite sequences of integers, the first author introduced the interesting arithmetic functions

g
k

g_k

(
k
∈

N

)

(k \in \mathbb {N})

, defined by

g
k

(
n
)
:=

n
(
n
+
1
)
…
(
n
+
k
)

lcm
⁡
(
n
,
n
+
1
,
…
,
n
+
k
)

g_k(n) := \frac {n (n + 1) \dots (n + k)} {\operatorname {lcm}(n, n+1, \dots , n + k)}

(
∀
n
∈

N

∖
{
0
}
)

(\forall n \in \mathbb {N} \setminus \{0\})

. He proved that for each

k
∈

N

k \in \mathbb {N}

,

g
k

g_k

is periodic and

k
!

k!

is a period of

g
k

g_k

. He raised the open problem of determining the smallest positive period

P
k

P_k

of

g
k

g_k

. Very recently, S. Hong and Y. Yang improved the period

k
!

k!

of

g
k

g_k

to

lcm
⁡
(
1
,
2
,
…
,
k
)

\operatorname {lcm}(1 , 2, \dots , k)

. In addition, they conjectured that

P
k

P_k

is always a multiple of the positive integer

lcm
⁡
(
1
,
2
,
…
,
k
,
k
+
1
)

k
+
1

\frac {\operatorname {lcm}(1 , 2 , \dots , k , k + 1)}{k + 1}

. An immediate consequence of this conjecture is that if

(
k
+
1
)

(k + 1)

is prime, then the exact period of

g
k

g_k

is precisely equal to

lcm
⁡
(
1
,
2
,
…
,
k
)

\operatorname {lcm}(1 , 2 , \dots , k)

.

In this paper, we first prove the conjecture of S. Hong and Y. Yang and then we give the exact value of

P
k

P_k

(
k
∈

N

)

(k \in \mathbb {N})

. We deduce, as a corollary, that

P
k

P_k

is equal to the part of

lcm
⁡
(
1
,
2
,
…
,
k
)

\operatorname {lcm}(1 , 2 , \dots , k)

not divisible by some prime.
Average behavior of Fourier coefficients of cusp forms
Authors: Lü Guangshi 
Published: February 2009

Let

a
0

(
n
)

a_0(n)

and

b
0

(
n
)

b_0(n)

be the normalized Fourier coefficients of the two holomorphic Hecke eigenforms

f
(
z
)
∈

S

2
k

(
Γ
)

f(z)\in S_{2k}(\Gamma )

and

φ
(
z
)
∈

S

2
l

(
Γ
)

\varphi (z)\in S_{2l}(\Gamma )

respectively. In 1999, Fomenko studied the following average sums of

a
0

(
n
)

a_0(n)

and

b
0

(
n
)

b_0(n)

:
\[

∑

n
≤
x

a
0

(
n

)
3

,

∑

n
≤
x

a
0

(
n

)
2

b
0

(
n
)
,

∑

n
≤
x

a
0

(
n

)
2

b
0

(
n

)
2

,

∑

n
≤
x

a
0

(
n

)
4

.

\sum _{n \leq x}a_0(n)^3, \quad \sum _{n \leq x}a_0(n)^2b_0(n), \quad \sum _{n \leq x}a_0(n)^2b_0(n)^2, \quad \sum _{n \leq x}a_0(n)^4.

\]
In this paper, we are able to improve on Fomenko’s results.
Minimal polynomial of an exponential automorphism of ℂⁿ
Authors: Zygadło Jakub 
Published: February 2009

We show that the minimal polynomial of a polynomial exponential automorphism

F
F

of

C

n

\mathbb {C}^n

(i.e.

F
=
exp
⁡
(
D
)

F=\exp (D)

where

D
D

is a locally nilpotent derivation) is of the form

μ
F

(
T
)
=
(
T
−
1

)
d

\mu _F(T)=(T-1)^d

, with

d
=
min
{
m
∈

N

:

D

∘
m

(

X
i

)
=
0
for
i
=
1
,
…
,
n
}

d=\min \{m\in \mathbb {N}: D^{\circ m}(X_i)=0\text { for } i=1,\ldots ,n\}

.
RAMI: a tool for identification and characterization of phylogenetic clusters in microbial communities
Authors: Pommier Thomas , Canbäck Björn , Lundberg Per , Hagström Åke , Tunlid Anders 
Published: February 2009

Abstract
Motivation: The most common approach to estimate microbial diversity is based on the analysis of DNA sequences of specific target genes including ribosomal genes. Commonly, the sequences are grouped into operational taxonomic units based on genetic distance (sequence similarity) instead of genetic change (patristic distance). This method may fail to adequately identify clusters of evolutionary related sequences and it provides no information on the phylogenetic structure of the community. An ease-of-use web application for this purpose has been missing.
Results: We have developed RAMI, which clusters related nodes in a phylogenetic tree based on the patristic distance. RAMI also produces indices of cluster properties and other indices used in population and community studies on-the-fly.
Availability: RAMI is licensed under GNU GPL and can be run or downloaded from http://www.acgt.se/online.html.
Contact: tpommier@univ-montp2.fr; bcanback@acgt.se
Supplementary information: http://www.acgt.se/RAMI/SuppInfo
Identification of differential gene pathways with principal component analysis
Authors: Ma Shuangge , Kosorok Michael R. 
Published: February 2009

Abstract
Motivation: Development of high-throughput technology makes it possible to measure expressions of thousands of genes simultaneously. Genes have the inherent pathway structure, where pathways are composed of multiple genes with coordinated biological functions. It is of great interest to identify differential gene pathways that are associated with the variations of phenotypes.
Results: We propose the following approach for detecting differential gene pathways. First, we construct gene pathways using databases such as KEGG or GO. Second, for each pathway, we extract a small number of representative features, which are linear combinations of gene expressions and/or their transformations. Specifically, we propose using (i) principal components (PCs) of gene expression sets, (ii) PCs of expanded gene expression sets and (iii) expanded sets of PCs of gene expressions, as the representative features. Third, we identify differential gene pathways as those with representative features significantly associated with the variations of phenotypes, particularly disease clinical outcomes, in regression models. The false discovery rate approach is used to adjust for multiple comparisons. Analysis of three gene expression datasets suggests that (i) the proposed approach can effectively identify differential gene pathways; (ii) PCs that explain only a small amount of variations of gene expressions may bear significant associations between gene pathways and phenotypes; (iii) including second-order terms of gene expressions may lead to identification of new differential gene pathways; (iv) the proposed approach is relatively insensitive to additional noises; and (v) the proposed approach can identify gene pathways missed by alternative approaches.
Contact: shuangge.ma@yale.edu
Supplementary information: Supplementary data are available at Bioinformatics online.
The solution structure of the anti‐HIV chemokine vMIP‐II
Authors: Liwang Andy C. , Wang Zi‐Xuan , Sun Yi , Peiper Stephen C. , Liwang Patricia J. 
Published: February 2009

AbstractWe report the solution structure of the chemotactic cytokine (chemokine) vMIP‐II. This protein has unique biological activities in that it blocks infection by several different human immunodeficiency virus type 1 (HIV‐1) strains. This occurs because vMIP‐II binds to a wide range of chemokine receptors, some of which are used by HIV to gain cell entry. vMIP‐II is a monomeric protein, unlike most members of the chemokine family, and its structure consists of a disordered N‐terminus, followed by a helical turn (Gln25‐Leu27), which leads into the first strand of a three‐stranded antiparallel β‐sheet (Ser29‐Thr34; Gly42‐Thr47; Gln52‐Asp56). Following the sheet is a C‐terminal α‐helix, which extends from residue Asp60 until Gln68. The final five residues beyond the C‐terminal helix (Pro70‐Arg74) are in an extended conformation, but several of these C‐terminal residues contact the first β‐strand. The structure of vMIP‐II is compared to other chemokines that also block infection by HIV‐1, and the structural basis of its lack of ability to form a dimer is discussed.
A stable intermediate in the equilibrium unfolding of Escherichia coli citrate synthase
Authors: Ayed Ayeda , Duckworth Harry W. 
Published: February 2009

AbstractUrea‐induced unfolding of Escherichia coli citrate synthase occurs in two phases, as monitored by circular dichroism at 222 nm (measuring secondary structure) or by tryptophan fluorescence. In this paper we characterize the intermediate state, which retains about 40% of the ellipticity of the native state, and is stable between 2.5 M and 5.5 M urea, approximately. This intermediate binds significant amounts of the probe for hydrophobic surfaces, anilinonaphthalene sulfonate, but forms aggregates at least as high as an octamer, as shown by transverse urea gradient polyacrylamide electrophoresis. Thermal denaturation of E. coli citrate synthase also produces an intermediate at temperatures near 60 °C, which also retains about 40% of the native ellipticity and forms aggregates, as measured by electrosprayionization/time‐of‐flight mass spectrometry. We have used a collection of “cavity‐forming” mutant proteins, in which bulky buried hydrophobic residues are replaced by alanines, to explore the nature of the intermediate state further. A certain amount of these mutant proteins shows a destabilized intermediate, as measured by the urea concentration range in which the intermediate is observed. These mutants are found in parts of the citrate synthase sequence that, in a native state, form helices G, M, N, Q, R, and S. From this and other evidence, it is argued that the intermediate state is an aggregated state in which these six helices, or parts of them, remain folded, and that formation of this intermediate is also likely to be a key step in the folding of E. coli citrate synthase.
Analysis of long‐range interactions in a model denatured state of staphylococcal nuclease based on correlated changes in backbone dynamics
Authors: Sinclair James F. , Shortle David 
Published: February 2009

AbstractAn expanded, highly dynamic denatured state of staphylococcal nuclease exhibits a native‐like topology in the apparent absence of tight packing and fixed hydrogen bonds (Gillespie JR, Shortle D, 1997, J Mol Biol 268:158–169, 170–184). To address the physical basis of the long‐range spatial ordering of this molecule, we probe the effects of perturbations of the sequence and solution conditions on the local chain dynamics of a denatured 101‐residue fragment that is missing the first three beta strands. Structural interactions between chain segments are inferred from correlated changes in the motional behavior of residues monitored by 15N NMR relaxation measurements. Restoration of the sequence corresponding to the first three beta strands significantly increases the average order of all chain segments that form the five strand beta barrel including loops but has no effect on the carboxy terminal 30 residues. Addition of the denaturing salt sodium perchlorate enhances ordering over the entire sequence of this fragment. Analysis of seven different substitution mutants points to a complex set of interactions between the hydrophobic segment corresponding to beta strand 5 and the remainder of the chain. General patterns in the data suggest there is a hierarchy of native‐like interactions that occur transiently in the denatured state and are consistent with the overall topology of the denatured state ensemble being determined by many coupled local interactions rather than a few highly specific long‐range interactions.
Dual coenzyme specificity of Archaeoglobus fulgidus HMG‐CoA reductase
Authors: Kim Dong‐Yul , Stauffacher Cynthia V. , Rodwell Victor W. 
Published: February 2009

AbstractComparison of the inferred amino acid sequence of orf AF1736 of Archaeoglobus fulgidus to that of Pseudomonas mevalonii HMG‐CoA reductase suggested that AF1736 might encode a Class II HMG‐CoA reductase. Following polymerase chain reaction‐based cloning of AF1736 from A. fulgidus genomic DNA and expression in Escherichia coli, the encoded enzyme was purified to apparent homogeneity and its enzymic properties were determined. Activity was optimal at 85°C,ΔHa was 54 kJ/mol, and the statin drug mevinolin inhibited competitively with HMG‐CoA (Ki 180 μM). Protonated forms of His390 and Lys277, the apparent cognates of the active site histidine and lysine of the P. mevalonii enzyme, appear essential for activity. The mechanism proposed for catalysis of P. mevalonii HMG‐CoA reductase thus appears valid for A. fulgidus HMG‐CoA reductase. Unlike any other HMG‐CoA reductase, the A. fulgidus enzyme exhibits dual coenzyme specificity. pH‐activity profiles for all four reactions revealed that optimal activity using NADP(H) occurred at a pH from 1 to 3 units more acidic than that observed using NAD(H). Kinetic parameters were therefore determined for all substrates for all four catalyzed reactions using either NAD(H) or NADP(H). NADPH and NADH compete for occupancy of a common site. kcat[NAD(H)]/kcat[NADP(H)] varied from unity to under 70 for the four reactions, indicative of slight preference for NAD(H). The results indicate the importance of the protonated status of active site residues His390 and Lys277, shown by altered KM and kcat values, and indicate that NAD(H) and NADP(H) have comparable affinity for the same site.
Preclinical and clinical studies of anticancer agent‐incorporating polymer micelles
Authors: Matsumura Yasuhiro , Kataoka Kazunori 
Published: February 2009

The size of anticancer agent‐incorporating micelles can be controlled within the diameter range of 20–100 nm to ensure that they do not penetrate normal vessel walls. With this development, it is expected that the incidence of drug‐induced side‐effects may be decreased owing to the reduced drug distribution in normal tissue. Micelle systems can also evade non‐specific capture by the reticuloendothelial system because the outer shell of a micelle is covered with polyethylene glycol. Consequently, a polymer micelle carrier can be delivered selectively to a tumor by utilizing the enhanced permeability and retention effect. Moreover, a water‐insoluble drug can be incorporated into polymer micelles. Presently, several anticancer agent‐incorporating micelle carrier systems are under preclinical and clinical evaluation. Furthermore, nucleic acid‐incorporating micelle carrier systems are also being developed. (Cancer Sci2009; 100: 572–579)