bluuebunny/crossref_metadata_2025 huggingface dataset:
Preliminary study of frontal lobe 1H MR spectroscopy in childhood‐onset schizophrenia
Authors: Thomas M. Albert , Ke Yong , Levitt Jennifer , Caplan Rochelle , Curran John , Asarnow Robert , McCracken James
Published: March 2007

Cerebral 1H MR spectra were recorded in 13 children and adolescents with schizophrenia and 12 healthy children and adolescents. Stimulated echo acquisition mode (STEAM) sequence was used to localize an 8‐ml voxel bilaterally in the frontal gray matter. The frontal gray matter metabolite ratios for NAA/Cr, Ch/Cr, Gix/Cr, and mI/Cr in schizophrenic children and adolescents were 1.08 ± .28, .64 ± .23, 1.09 ± .30, and .60 ± .24, respectively. In comparison, these ratios were 1.59 ± .35, .74 ± .27, 1.23 ± .36, and .58 ± .29 in healthy children and adolescents. Decrease in the frontal lobe NAA/Cr of schizophrenic children and adolescents was statistically significant (P < .001). In contrast, the MR spectra localized bilaterally in the occipital gray matter (8 ml) showed no significant changes between the patients and the controls. In the occipital gray matter, the metabolite ratios were 1.21 ± .26, .52 ± .08, 1.00 ± .11, and .55 ± .12 in patients versus 1.30 ± .23, .45 ± .10, 1.15 ± .20, and .48 ± .19 in controls. Our preliminary finding of reduced NAA/Cr ratio in the frontal gray matter is consistent with the neurodevelopmental models emphasizing dysfunction of frontal lobe areas in patients with schizophrenia.
Optimal dose of hepatobiliary contrast agent for MR cholangiography: Experimental study in rats
Authors: Hirohashi Shinji , Hirohashi Rina , Uchida Hideo , Kitano Satoru , Akira Megumi , Ono Wataru , Ohishi Hajime , Kato Naoki , Takahashi Masaya , Miyazawa Tomoaki
Published: March 2007

The purpose of this study is to clarify the optimal dose of gadolinium‐ethoxybenzyl‐diethylenetriaminepentaacetic acid (Gd‐EOB‐DTPA) for cholangiography in conventional T1‐weighted imaging. We divided 30 rats into three dose groups (3, 10, and 30 μmol/kg). For the in vitro study, we collected bile and measured the concentration of gadolinium in bile after Gd‐EOB‐DTPA injection. T1‐weighted images of the collected bile were obtained for measurement of signal intensity. For the in vivo study, we obtained T1‐weighted images before and after injection and evaluated bile duct/liver contrast by the signal intensity ratio and visual assessment of the images. The gadolinium concentration had an early peak; however, the signal intensity of the bile had a later peak because of the high gadolinium concentration during the early phase, which induced a T2‐shortening effect. Optimal bile duct/liver contrast was obtained in the 10‐μmol/kg groups at all time points. We conclude that the optimal dose of Gd‐EOB‐DTPA for MR cholangiography in rats is 10 μmol/kg, one‐third of the dose used in liver imaging.
Impact of climate variability on Alpine glaciers in northwestern Italy
Authors: Calmanti Sandro , Motta Luigi , Turco Marco , Provenzale Antonello
Published: March 2007

We analyzed glacier snout fluctuation data in Piedmont and Val d'Aosta (Italy) and studied the impact of climate variability on valley glaciers in the western Italian Alps. The study period covered about 70 years in the 20th century; we focused on the last 50 years where a large number of temperature and precipitation time series are available. Superposed onto a general recession trend, we detected strong oscillations on shorter time scales and we showed that they are significantly correlated with fluctuations in winter precipitation rates and average summer temperatures. On the basis of these results, we constructed a simple lagged‐linear empirical stochastic model that explained upto 66% of the variance of the snout fluctuation data. The model produces reliable out‐of‐sample predictions of the impact of climate variability on the glaciers of the western Alps and it can be used to estimate the average response of Alpine glaciers to different scenarios of climate change, provided the morphology of the individual glaciers does not change completely. Copyright © 2007 Royal Meteorological Society
Predictors of quality of life in old age: A cross‐validation study
Authors: Low Gail , Molzahn Anita E.
Published: March 2007

A replication study was undertaken to validate a model of quality of life (QOL) generated in an earlier study on a random sample of 202 older adults. Pathways found to be significant were retested using QOL data from a convenience sample of 420 older adults. Using path analysis, we found that financial resources, health, and meaning in life directly and positively influenced QOL. Health, emotional support, and the physical environment indirectly affected QOL through purpose in life. All but one pathway were replicated, explaining 50.5% of the variance in QOL. Further explorations of the influence of spirituality, emotionally close ties, and opportunities for active engagement on QOL in older age are warranted. © 2007 Wiley Periodicals, Inc. Res Nurs Health 30: 141–150, 2007
Prenatal diagnosis of complete atrioventricular septal defect with truncus arteriosus
Authors: Chintala Kavitha , Gurczynski Jody , Aggarwal Sanjeev
Published: March 2007

Truncus arteriosus (TA) is a rare cardiac anomaly constituting less than 1% of all congenital heart defects. Its association with complete atrioventricular septal defect (AVSD) is extremely unusual and only 12 cases diagnosed postnatally or postmortem have been reported so far. We describe the first case of truncus arteriosus with AVSD to be diagnosed prenatally by fetal echocardiography. Copyright © 2007 John Wiley & Sons, Ltd.
Development of a polyester‐rubber adhesive
Authors: Mather J.
Published: March 2007

The historical development of the polyester‐rubber adhesive Pexul is described. This substance can be used in single‐ or two‐stage dipping in conjunction with a resorcinol‐formaldehyde latex for the adhesion of polyester cords to rubber.

The most effective formulation is a molecule consisting of two molecules of resorcinol linked to a central p‐chlorophenol molecule by means of formaldehyde (methylene links), but the commercial product contains many related compounds.

Its mode of action is postulated to be (a) adhesion of the substance to the surface of the polyester as a result of good matching of the cohesive energy densities and hydrogen bonding between the polyester oxygen atoms and the phenolic hydroxyls; and (b) thermal polycondensation of the surface film to give a strongly adherent crosslinked film which simultaneously or subsequently reacts with RF‐latex to form a complete system capable of bonding to rubber.

The determination of Pexul on dipped cords by chlorine analysis and by the use of trace metals and X‐ray fluorescence is described.
Hydration of a hydrophobic cavity and its functional role: A simulation study of human interleukin‐1β
Authors: Somani Sandeep , Chng Choon‐Peng , Verma Chandra S.
Published: March 2007

Molecular dynamics simulations reveal that the hydrophobic cavity in human cytokine Interleukin‐1β is hydrated and can dynamically accommodate between one and four water molecules. These waters have residence times >> 500 ps and can give rise to detectable NOEs, in agreement with NMR observations of Ernst et al. (Science 1995; 267:1813–1817). The waters also display high positional disorder within the cavity, which explains why they have not been resolved crystallographically. The average distribution of water molecules over time within the cavity matches well the low resolution electron density extracted by Yu et al. (Proc Natl Acad Sci 1999; 96:103–108). The water molecules hydrate the hydrophobic cavity preferentially as complex clusters. These clusters result from a combination of hydrogen bonds between the waters and stabilizing interactions between the waters and aromatic rings forming the cavity. Free energy estimates suggest that it takes 4‐waters to hydrate the cavity in a thermodynamically stable manner leading to a gain in free energy of transfer from bulk of ∼∼3.6 kcal/mol. This arises from the existence of the water clusters in multiple hydrogen bonded states. In addition, the waters are found to migrate either individually or as clusters out of the cavity through several pathways. The upper limit for one‐dimensional diffusion of the waters within the protein matrix is 4 Å/ps (relative to 6 Å/ps for bulk). Simulations reveal pathways in addition to those identified crystallographically, with motions controlled by the rotations of sidechains. We find that only when the hydrophobic cavity is hydrated, do correlated motions couple distant sites with the sites that make contact with the receptor and this data partly offers an explanation of experimental mutagenesis data. Simulations, together with recent observations based on mutagenesis by Heidary et al. (J Mol Biol 2005; 353:1187–1198) that hydrogen bond networks couple motions across long distances in interleukin‐1 β, lead us to hypothesize that the hydration of the cavity (conserved across mammals) can thermodynamically enhance hydrogen bond networks to enable coupling across long distances by acting as a plug and this in turn enables a kinetic control of the rate of transmission of signals. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Strategies for managing a portfolio of alliances
Authors: Hoffmann Werner H.
Published: March 2007

Interorganizational relationships are recognized as an increasingly important source of competitive advantage. Hence, goal‐oriented management of the alliance portfolio—all the alliances of the focal firm—plays a decisive role in company performance. Consequently, the configuration and development of the alliance portfolio become important strategic issues. In light of that, this article develops theoretical propositions that seek to clarify what determines the configuration and evolution of an alliance portfolio, and then presents the results of a longitudinal study to illustrate the developed theoretical framework. Building on contingency theory and a coevolutionary framework, we were able to identify three distinctive types of portfolio strategies at business level and to illustrate how they interact with the development of the business strategy and the business environment. Encompassing all this, the study illustrates and explains developmental paths and patterns in the evolution of an alliance portfolio. The developmental course typically evolves from adapting to shaping and to exploiting (stabilizing), according to the state of strategic uncertainty and the firm's resource endowment. A sudden increase in exogenous strategic uncertainty, however, can lead to a strategic shift back to an exploration or hybrid strategy. Copyright © 2007 John Wiley & Sons, Ltd.
Dietary linoleic, α‐linolenic and oleic acids are oxidized at similar rates in rats fed a diet containing these acids in equal proportions
Authors: Jones Peter J. H.
Published: March 2007

The objective of this study was to examine whether whole body oxidation rates of dietary linoleic, α‐linolenic and oleic acids differ when the acids are provided in identical quantities. Male rats were fed for 10 wk a 15% fat (w/w) diet containing equal amounts of linoleic, α‐linolenic and oleic acids (22.7, 23.0 and 23.2% of total fatty acids, respectively). At week 10, after overnight fasting, rats were intragastrically administered 20 μCi of either [1‐14C]‐labelled linoleic, α‐linolenic or oleic acid in a 200‐μL bolus of oil containing equal quantities of each fatty acid. The appearance of14CO2 in expired air was then monitored hourly for 12h for each animal. A preliminary study had shown that growth and food consumption patterns in animals consuming the oil containing equal quantities of each of the fatty acids paralleled the patterns of animals that were self‐selecting among separate diets, each of which contained one of the component oils. The appearance of14C, expressed as percent dose administered, peaked at 2–3 h post‐dose for14C‐labelled linoleic (5.28±0.37%/h), α‐linolenic (6.92±0.51%/h) and oleic (5.98±0.44%/h) acids. Statistically these values were not significantly different. Cumulative14CO2 excretion rates over 12 h were also similar for linoleic (27.2±0.9%), α‐linolenic (26.8±1.2%) and oleic (25.9±1.2%) acids. The results suggest that the rat's capacity to oxidize 18‐carbon unsaturated fatty acids is not affected by fatty acid unsaturation when these fatty acids are provided at equal dietary levels.
The distribution of brominated long‐chain fatty acids in sponge and symbiont cell types from the tropical marine spongeAmphimedon terpenensis
Authors: Garson Mary J. , Zimmermann Mary P. , Battershill Christopher N. , Holden Janet L. , Murphy Peter T.
Published: March 2007

The tropical marine spongeAmphimedon terpenensis (family Niphatidae, order Haplosclerida) has previously been shown to possess unusual lipids, including unusual fatty acids. The biosynthetic origin of these fatty acids is of interest as the sponge supports a significant population of eubacterial and cyanobacterial symbionts. The total fatty acid composition of the sponge was analyzed by gas chromatography/mass spectrometry of the methyl esters. Among the most abundant of the fatty acids in intact tissue were 16∶0, 18∶0 and 3,7,11,15‐tetramethylhexadecanoic (phytanic) acid. In addition, three brominated fatty acids, (5E,9Z)‐6‐bromo‐5,9‐tetracosadienoic acid (24∶2Br), (5E,9Z)‐6‐bromo‐5,9‐pentacosadienoic acid (25∶2Br) and (5E,9Z)‐6‐bromo‐5,9‐hexacosadienoic acid (26∶2Br) were also present. The three brominated fatty acids, together with phytanic acid, were isolated from both ectosomoal (superficial) and choanosomal (internal) regions of the sponge. Analysis of extracts prepared from sponge/symbiont cells, partitioned by density gradient centrifugation on Ficoll, indicated that phytanic acid and the three brominated fatty acids were associated with sponge cells only. Further, a fatty acid methyl ester sample from intact tissue ofA. terpenensis was partitioned according to phospholipid class, and the brominated fatty acids were shown to be associated with the phosphatidylserine and phosphatidylethanolamine fractions that are commonly present in marine sponge lipids. The phosphatidylcholine and phosphatidylglycerol fractions were rich in the relatively shorter chain fatty acids (16∶0 and 18∶0). The association of brominated long‐chain fatty acids (LCFA) with sponge cells has been confirmed. The findings allow comment on the use of fatty acid profiles in chemotaxonomy and permit further interpretation of LCFA biosynthetic pathways in sponges. The assignment of the sponge studied, which is currently placed asA. terpenensis, is being supported to some extent, but the species is unusual in having C25 fatty acids as the major constituent in this group. Other factors, such as season or microenvironmental conditions, may influence observed fatty acid composition which tends to reduce the usefulness of fatty acid profiles as markers in sponge chemotaxonomy.
The hydrolysis of soap solutions. III. Values of pH and the absence of fatty acid as free liquid or solid
Authors: McBain James W. , Laurent P. , John Lucille M.
Published: March 2007

The pH of the laurates, myristates, palmitates, and stearates of sodium and potassium at 25° and 50°C. was determined by use of a glass electrode. pH:concentration curves were constructed, and hydroxyl ion activity was calculated. In general, the concentration of hydroxyl ion ranges from 0.001 to 0.0001 N; for the less dilute solutions of the higher soaps, the upper limit is exceeded by several fold, and in the more dilute solutions the concentration may fall beneath the lower value. Solubilized hexane reduced the pH of potassium and sodium laurate but very slightly. Potassium or sodium chloride reduced the pH of soap solutions over a certain range but caused a slight increase in a narrow intermediate range.

Using the pH values obtained, the actual concentration of fatty acid in the soap solutions was calculated, and was found to beless than the saturation concentrations obtained by conductivity measurements through the entire range investigated. Free fatty acid therefore never separates as such from pure soap solutions unless acted upon by excess of acid such as carbon dioxide.

Percentage hydrolysis was calculated and curves were constructed. In general, the potassium soaps are hydrolyzed more than the corresponding sodium soaps; the difference is slight for the laurates but is considerably greater for the myristates, palmitates, and stearates in higher concentrations at 25°C. The difference is appreciably smaller at 50° than at 25°. Percentage hydrolysis for the laurates is very much less than for the higher soaps.
Management of Combined Open Fractures of Thumb Metacarpal and Trapezium (Surgical Tip)
Authors: Pehlivan Ozcan , Cilli Feridun , Mahirogullari Mahir , Ozyurek Selahattin
Published: March 2007

Management of an unusual injury of combined open fractures of the first metacarpal shaft and trapezium due to crush injury in a 21-year-old man was reported in this paper. Surgical management included irrigation, debridement, and reduction of the first metacarpal fracture followed by external fixation extending from the first metacarpal to the distal radius and primary wound closure. After 1 year of surgery, follow-up functional and radiographic evaluations were satisfactory, and most of the daily activities were pain-free.
Flexor Tendon Sheath Ganglions: Results of Surgical Excision
Authors: Jebson Peter J. L. , Spencer Edwin E.
Published: March 2007

The purpose of our study was to review the clinical features and determine the results following surgical excision of a flexor tendon sheath ganglion. A retrospective analysis of 24 consecutive patients (25 ganglions) who underwent excision of a painful flexor tendon sheath ganglion by the same surgeon was performed. The patient's medical and operative records were reviewed. Each patient was invited to return for an evaluation, which consisted of a clinical interview, completion of a questionnaire, and physical examination. Those patients that were unable to return underwent a detailed telephone interview. Sixteen patients returned for a clinical evaluation, while eight patients underwent a telephone interview. There were 15 women and nine men, with an average age of 43 years (range, 21–68 years). The dominant hand was involved in 15 patients. The long finger was most commonly involved (11 cases). The ganglion arose from the A1 pulley in 13 cases, between the A1 and A2 pulleys in three cases, and from the A2 pulley in nine cases. At an average follow-up of 18.5 months (range, 5–38 months), all of the patients were satisfied with their final result. No patient developed a recurrence and all returned to their previous functional level. There were two minor complications that resolved uneventfully; one patient experienced mild incisional tenderness, while an additional patient experienced transient digital nerve paresthesias. We conclude that surgical excision is a simple, safe, and effective method for treating a painful ganglion of the digital flexor tendon sheath.
Synergistic action of polyanionic and non‐polar cofactors in fibrillation of human islet amyloid polypeptide
Authors: Konno Takashi , Oiki Shigetoshi , Morii Takashi
Published: March 2007

Recent studies have led us to suppose that synergistic action of multiple solute cofactors could play substantial roles in amyloid‐type fibrillogenesis of pathogenic polypeptides. To support this view, we performed aggregation experiments of human islet amyloid polypeptide (IAPP) in media containing both polyanions and non‐polar solvents. The results demonstrated that the fibrillation at sub‐micromolar IAPP occurred only when polyanionic and non‐polar solutes coexist. A simple sum of two independent cofactor's effects could not account for the synergistic action. We propose that this synergy of polyanionic and nonpolar milieus could substantially modify the amyloidgenesis in the human body.
Doppler ducting of short‐period gravity waves by midlatitude tidal wind structure
Authors: Snively Jonathan B. , Pasko Victor P. , Taylor Michael J. , Hocking Wayne K.
Published: March 2007

Multiwavelength airglow image data depicting a short‐period (∼4.9 min) atmospheric gravity wave characterized by a sharp leading front have been analyzed together with synoptic meteor radar wind data recorded simultaneously from Bear Lake Observatory, Utah (41.6°N, 111.6°W). The wind data suggest the presence of a semidiurnal tide with horizontal winds peaking at around 60 m/s along the SSE direction of motion (170° from north) of this short‐period wave. It was found that the gravity wave was most probably ducted because of the Doppler shift imposed by this wind structure. A marked 180° phase shift was observed between the near‐infrared OH and the OI (557.7 nm) emissions. Numerical simulation results for similar ducted waves excited by idealized model sources suggest that the phase shift between the wave‐modulated airglow intensities may be explained simply by chemical processes rather than by wave dynamics. Phase velocities of simulated waves, however, appear higher than those of observed waves, suggesting the importance of tidal thermal structure in determining the Doppler‐ducted wave characteristics.
Sea ice drift variability in Arctic Ocean Model Intercomparison Project models and observations
Authors: Martin Torge , Gerdes Rüdiger
Published: March 2007

Drift is a prominent parameter characterizing the Arctic sea ice cover that has a deep impact on the climate system. Hence it is a key issue to both the remote sensing as well as the modeling community, to provide reliable sea ice drift fields. This study focuses on the comparison of sea ice drift results from different sea ice‐ocean coupled models and the validation with observational data in the period 1979–2001. The models all take part in the Arctic Ocean Model Intercomparison Project (AOMIP) and the observations are mainly based on satellite imagery. According to speed distributions, one class of models has a mode at drift speeds around 3 cm s−1 and a short tail toward higher speeds. Another class shows a more even frequency distribution with large probability of drift speeds of 10 to 20 cm s−1. Observations clearly agree better with the first class of model results. Reasons for these differences are manifold and lie in discrepancies of wind stress forcing as well as sea ice model characteristics and sea ice‐ocean coupling. Moreover, we investigated the drift patterns of anticyclonic and cyclonic wind‐driven regimes. The models are capable of producing realistic drift pattern variability. The winter of 1994/1995 stands out because of its maximum in Fram Strait ice export. Although export estimates of some models agree with observations, the corresponding inner Arctic drift pattern is not reproduced. The reason for this is found in the wind‐forcing as well as in differences in ocean velocities.
Deformation process and kinematics of mélange in the Early Cretaceous accretionary complex of the Mino‐Tamba Belt, eastern southwest Japan
Authors: Fukui Akiko , Kano Ken‐ichi
Published: March 2007

The Kanayama unit of the Mesozoic Mino‐Tamba accretionary complex in eastern southwest Japan is a thick mélange unit composed mainly of abundant muddy matrix and variously sized clasts of chert, hemipelagic siliceous mudstone, and sandstone. Two episodes of deformation formed the mélange fabrics: the first involved fragmentation of sandstone layers in response to mud injections; the second involved layer‐parallel, noncoaxial shear that resulted in the mixing of pelagic to terrigenous clasts and the formation of S‐C‐like asymmetric fabrics with scaly foliation. The S‐C fabrics exhibit a predominantly sinistral shear sense in plan view. After fold and tilt corrections, the restored slip motion inferred from the S‐C fabrics indicates a bulk top‐to‐the‐south shear. Combining the unit's terminal fossil age and radiometric age with a regional plate reconstruction model, these data suggest that the Kanayama mélange formed along a décollement during oblique subduction of the Izanagi plate in the Early Cretaceous.
Theoretical transition probabilities for the OH Meinel system
Authors: van der Loo Mark P. J. , Groenenboom Gerrit C.
Published: March 2007

The authors present a new potential energy curve, electric dipole moment function, and spin-orbit coupling function for OH in the XΠ2 state, based on high-level ab initio calculations. These properties, combined with a spectroscopically parametrized lambda-type doubling Hamiltonian, are used to compute the Einstein A coefficients and photoabsorption cross sections for the OH Meinel transitions. The authors investigate the effect of spin-orbit coupling on the lifetimes of rovibrationally excited states. Comparing their results with earlier ab initio calculations, they conclude that their dipole moment and potential energy curve give the best agreement with experimental data to date. The results are made available via EPAPS Document No. E-JCPSAG-017709.
The ecology of the rufous treecreeper in the jarrah forest of south-western Australia and implications for its conservation and management
Authors: Craig Michael D.
Published: March 2007

Rufous treecreepers (Climacteris rufa) are common in southern jarrah forests of Western Australia, but nothing has been recorded of their ecology in the region. I investigated the foraging and nesting ecology of the species in the southern jarrah forests from January 1994 to April 1996. Rufous treecreepers foraged exclusively on two eucalypt species, jarrah and marri, and foraged on trees that were significantly larger and taller than random. Foraging on the ground, logs and fallen trees was relatively infrequent. Nest hollows were also located exclusively in jarrah and marri trees that were significantly larger and taller than random. The important foraging and nesting resources for the species in the southern jarrah forest appear to be large mature and overmature eucalypts. Anthropogenic impacts in the region, primarily logging, should aim to retain these resources in affected areas to improve the survival prospects of the species. When compared with studies in wandoo woodlands, the results of the present study indicate that the conservation of ground-layer habitat is likely to be of less importance in the jarrah forest. These habitat differences indicate that site-specific information is critical if the management and conservation of individual species is to be effective.
Ott1
(
Rbm15
) has pleiotropic roles in hematopoietic development
Authors: Raffel Glen D. , Mercher Thomas , Shigematsu Hirokazu , Williams Ifor R. , Cullen Dana E. , Akashi Koichi , Bernard Olivier A. , Gilliland D. Gary
Published: March 2007

OTT1
(
RBM15
) was originally described as a 5′ translocation partner of the
MAL
(
MKL1
) gene in t(
1
,
22
)(p13;q13) infant acute mega karyocytic leukemia.
OTT1
has no established physiological function, but it shares homology with the
spen
/
Mint
/
SHARP
family of proteins defined by three amino-terminal RNA recognition motifs and a carboxyl-terminal SPOC (Spen paralog and ortholog carboxyl-terminal) domain believed to act as a transcriptional repressor. To define the role of
OTT1
in hematopoiesis and help elucidate the mechanism of t(
1
,
22
) acute megakaryocytic leukemia pathogenesis, a conditional allele of
Ott1
was generated in mice. Deletion of
Ott1
in adult mice caused a loss of peripheral B cells due to a block in pro/pre-B differentiation. There is myeloid and megakaryocytic expansion in spleen and bone marrow, an increase in the Lin
−
Sca-1
+
c-Kit
+
compartment that includes hematopoietic stem cells, and a shift in progenitor fate toward granulocyte differentiation. These data show a requirement for
Ott1
in B lymphopoiesis, and inhibitory roles in the myeloid, megakaryocytic, and progenitor compartments. The ability of
Ott1
to affect hematopoietic cell fate and expansion in multiple lineages is a novel attribute for a
spen
family member and delineates
Ott1
from other known effectors of hematopoietic development. It is plausible that dysregulation of
Ott1
-dependent hematopoietic developmental pathways, in particular those affecting the megakaryocyte lineage, may contribute to
OTT1-MAL
-mediated leukemogenesis.
Hyperconserved CpG domains underlie Polycomb-binding sites
Authors: Tanay Amos , O'Donnell Anne H. , Damelin Marc , Bestor Timothy H.
Published: March 2007

Comparative genomics of CpG dinucleotides, which are targets of DNA methyltransferases in vertebrate genomes, has been constrained by their evolutionary instability and by the effect of methylation on their mutation rates. We compared the human and chimpanzee genomes to identify DNA sequence signatures correlated with rates of mutation at CpG dinucleotides. The new signatures were used to develop robust comparative genomics of CpG dinucleotides in heterogeneous regions and to identify genomic domains that have anomalous CpG divergence rates. The data showed that there are ≈200 genomic regions where CpG distributions are far more conserved than predicted. These hyperconserved CpG domains largely coincide with domains bound by Polycomb repressive complex 2 in undifferentiated human embryonic stem cells and are almost exclusively present near genes whose products are involved in the regulation of embryonic development. Several domains were experimentally shown to be unmethylated at different developmental stages. These data indicate that particular evolutionary patterns and distinct sequence properties on scales much larger than standard transcription factor-binding sites may play an important role in Polycomb recruitment and transcriptional regulation of key developmental genes.
Noncoherence of some rings of functions
Authors: Sasane Amol
Published: March 2007

Let

D

\mathbb D

,

T

\mathbb T

denote the unit disc and unit circle, respectively, in

C

\mathbb C

, with center

0
0

. If

S
⊂

T

S\subset \mathbb T

, then let

A

S

A_{S}

denote the set of complex-valued functions defined on

D

∪
S

\mathbb D\cup S

that are analytic in

D

\mathbb D

, and continuous and bounded on

D

∪
S

\mathbb D\cup S

. Then

A

S

A_{S}

is a ring with pointwise addition and multiplication. We prove that if the intersection of

S
S

with the set of limit points of

S
S

is not empty, then the ring

A

S

A_{S}

is not coherent.
Some results on the Hochschild cohomology of group algebras
Authors: Pourabbas A.
Published: March 2007

In this paper we investigate structure of the second cohomology of a discrete group

G
G

. First, for a

G
G

-set

S
S

we show that an isomorphism of vector spaces from
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="script upper H Superscript n Baseline left-parenthesis script l Superscript 1 Baseline left-parenthesis upper G right-parenthesis comma script l Superscript normal infinity Baseline left-parenthesis upper S right-parenthesis right-parenthesis">

H

n

(

ℓ
1

(
G
)
,

ℓ
∞

(
S
)
)

\mathcal {H}^n(\ell ^1(G),\ell ^\infty (S))

onto
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="circled-plus Underscript i element-of upper I Overscript normal infinity Endscripts script upper H Superscript n Baseline left-parenthesis script l Superscript 1 Baseline left-parenthesis upper G right-parenthesis comma script l Superscript normal infinity Baseline left-parenthesis double-struck upper C right-parenthesis right-parenthesis">

⨁

i
∈
I

∞

H

n

(

ℓ
1

(
G
)
,

ℓ
∞

(

C

)
)

\bigoplus _{i\in I}^\infty \mathcal {H}^n(\ell ^1(G),\ell ^\infty (\mathbb {C}))

exists, where

{

C

i

}

i
∈
I

\{\mathcal {C}_{i}\}_{i\in I}

is the set of orbits of

S
S

. Next we define the notion of pseudoderivation and apply it for the calculation of
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="script upper H Subscript b comma 2 Superscript 2 Baseline left-parenthesis script l Superscript 1 Baseline left-parenthesis upper G right-parenthesis comma script l Superscript normal infinity Baseline left-parenthesis upper S right-parenthesis right-parenthesis">

H

b
,
2

2

(

ℓ
1

(
G
)
,

ℓ
∞

(
S
)
)

\mathcal {H}_{b,2}^2(\ell ^1(G),\ell ^\infty (S))

.
Operator theory on noncommutative varieties, II
Authors: Popescu Gelu
Published: March 2007

An

n
n

-tuple of operators

T
:=
[

T
1

,
…
,

T
n

]

T:=[T_1,\ldots , T_n]

on a Hilbert space

H

\mathcal {H}

is called a

J
J

-constrained row contraction if

T
1

T
1
∗

+
⋯
+

T
n

T
n
∗

≤

I

H

T_1T_1^*+\cdots + T_nT_n^*\leq I_\mathcal {H}

and
\[

f
(

T
1

,
…
,

T
n

)
=
0
,

f
∈
J
,

f(T_1,\ldots , T_n)=0,\quad f\in J,

\]
where

J
J

is a WOT-closed two-sided ideal of the noncommutative analytic Toeplitz algebra

F
n
∞

F_n^\infty

and

f
(

T
1

,
…
,

T
n

)

f(T_1,\ldots , T_n)

is defined using the

F
n
∞

F_n^\infty

–functional calculus for row contractions. We show that the constrained characteristic function

Θ

J
,
T

\Theta _{J,T}

associated with

J
J

and

T
T

is a complete unitary invariant for

J
J

-constrained completely non-coisometric (c.n.c.) row contractions. We also provide a model for this class of row contractions in terms of the constrained characteristic functions. In particular, we obtain a model theory for

q
q

-commuting c.n.c. row contractions.
Triple product identity, Quintuple product identity and Ramanujan’s differential equations for the classical Eisenstein series
Authors: Chan Heng Huat
Published: March 2007

In this article, we use the triple product identity and the quintuple product identity to derive Ramanujan’s famous differential equations for the Eisenstein series.
Oversampling generates super-wavelets
Authors: Dutkay Dorin , Jorgensen Palle
Published: March 2007

We show that the second oversampling theorem for affine systems generates super-wavelets. These are frames generated by an affine structure on the space
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="ModifyingBelow upper L squared left-parenthesis double-struck upper R Superscript d Baseline right-parenthesis circled-plus period period period circled-plus upper L squared left-parenthesis double-struck upper R Superscript d Baseline right-parenthesis With bottom-brace Underscript p times Endscripts">

L
2

(

R

d

)
⊕
.
.
.
⊕

L
2

(

R

d

)

⏟

p
 

times

\underbrace {L^2(\mathbb {R}^d) \oplus ...\oplus L^2(\mathbb {R}^d)}_{p\ \mbox {times}}

.
Maharam algebras and Cohen reals
Authors: Farah Ilijas , Veličković Boban
Published: March 2007

We show that the product of any two nonatomic Maharam algebras adds a Cohen real. As a corollary of this and a result of Shelah (1994) we obtain that the product of any two nonatomic ccc Souslin forcing notions adds a Cohen real.
Boundary blow-up in nonlinear elliptic equations of Bieberbach–Rademacher type
Authors: Cîrstea Florica-Corina , Rădulescu Vicenţiu
Published: March 2007

We establish the uniqueness of the positive solution for equations of the form−Δu=au−b(x)f(u)-\Delta u=au-b(x)f(u)inΩ\Omega,u|∂Ω=∞u|_{\partial \Omega }=\infty. The special feature is to consider nonlinearitiesffwhose variation at infinity isnot regular(e.g.,exp⁡(u)−1\exp (u)-1,sinh⁡(u)\sinh (u),cosh⁡(u)−1\cosh (u)-1,exp⁡(u)log⁡(u+1)\exp (u)\log (u+1),uβexp⁡(uγ)u^\beta \exp (u^\gamma ),β∈R\beta \in {\mathbb R},γ>0\gamma >0orexp⁡(exp⁡(u))−e\exp (\exp (u))-e) and functionsb≥0b\geq 0inΩ\Omegavanishing on∂Ω\partial \Omega. The main innovation consists of using Karamata’s theory not only in the statement/proof of the main result but also to link the nonregular variation offfat infinity with the blow-up rate of the solution near∂Ω\partial \Omega.
Analytic contractions, nontangential limits, and the index of invariant subspaces
Authors: Aleman Alexandru , Richter Stefan , Sundberg Carl
Published: March 2007

Let

H

\mathcal {H}

be a Hilbert space of analytic functions on the open unit disc

D

\mathbb {D}

such that the operator

M

ζ

M_{\zeta }

of multiplication with the identity function

ζ
\zeta

defines a contraction operator. In terms of the reproducing kernel for

H

\mathcal {H}

we will characterize the largest set

Δ
(

H

)
⊆
∂

D

\Delta (\mathcal {H}) \subseteq \partial \mathbb {D}

such that for each

f
,
g
∈

H

f, g \in \mathcal {H}

,

g
≠
0

g \ne 0

the meromorphic function

f

/

g

f/g

has nontangential limits a.e. on

Δ
(

H

)

\Delta (\mathcal {H})

. We will see that the question of whether or not

Δ
(

H

)

\Delta (\mathcal {H})

has linear Lebesgue measure 0 is related to questions concerning the invariant subspace structure of

M

ζ

M_{\zeta }

. We further associate with

H

\mathcal {H}

a second set

Σ
(

H

)
⊆
∂

D

\Sigma (\mathcal {H}) \subseteq \partial \mathbb {D}

, which is defined in terms of the norm on

H

\mathcal {H}

. For example,

Σ
(

H

)

\Sigma (\mathcal {H})

has the property that

|

|

ζ

n

f

|

|

→
0

||\zeta ^{n}f|| \to 0

for all

f
∈

H

f \in \mathcal {H}

if and only if

Σ
(

H

)

\Sigma (\mathcal {H})

has linear Lebesgue measure 0. It turns out that

Δ
(

H

)
⊆
Σ
(

H

)

\Delta (\mathcal {H}) \subseteq \Sigma (\mathcal {H})

a.e., by which we mean that

Δ
(

H

)
∖
Σ
(

H

)

\Delta (\mathcal {H}) \setminus \Sigma (\mathcal {H})

has linear Lebesgue measure 0. We will study conditions that imply that

Δ
(

H

)
=
Σ
(

H

)

\Delta (\mathcal {H}) = \Sigma (\mathcal {H})

a.e.. As one corollary to our results we will show that if dim

H

/

ζ

H

=
1

\mathcal {H}/\zeta \mathcal {H} =1

and if there is a

c
>
0

c>0

such that for all

f
∈

H

f \in \mathcal {H}

and all

λ
∈

D

\lambda \in \mathbb {D}

we have
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="StartAbsoluteValue EndAbsoluteValue StartFraction zeta minus lamda Over 1 minus lamda overbar zeta EndFraction f StartAbsoluteValue EndAbsoluteValue greater-than-or-equal-to c StartAbsoluteValue EndAbsoluteValue f StartAbsoluteValue EndAbsoluteValue">

|

|

ζ
−
λ

1
−

λ
¯

ζ

f

|

|

≥
c

|

|

f

|

|

||\frac {\zeta -\lambda }{1-\overline {\lambda }\zeta }f||\ge c||f||

, then

Δ
(

H

)
=
Σ
(

H

)

\Delta (\mathcal {H}) =\Sigma (\mathcal {H})

a.e. and the following four conditions are equivalent: (1)

|

|

ζ

n

f

|

|

↛
0

||\zeta ^{n} f||\nrightarrow 0

for some

f
∈

H

f \in \mathcal {H}

, (2)

|

|

ζ

n

f

|

|

↛
0

||\zeta ^{n} f||\nrightarrow 0

for all

f
∈

H

f \in \mathcal {H}

,

f
≠
0

f \ne 0

, (3)

Δ
(

H

)

\Delta (\mathcal {H})

has nonzero Lebesgue measure, (4) every nonzero invariant subspace

M

\mathcal {M}

of

M

ζ

M_{\zeta }

has index 1, i.e., satisfies dim

M

/

ζ

M

=
1

\mathcal {M}/\zeta \mathcal {M} =1

.
The arithmetic and combinatorics of buildings for 𝑆𝑝_{𝑛}
Authors: Shemanske Thomas
Published: March 2007

In this paper, we investigate both arithmetic and combinatorial aspects of buildings and associated Hecke operators for

S

p
n

(
K
)

Sp_n(K)

with

K
K

a local field. We characterize the action of the affine Weyl group in terms of a symplectic basis for an apartment, characterize the special vertices as those which are self-dual with respect to the induced inner product, and establish a one-to-one correspondence between the special vertices in an apartment and the elements of the quotient

Z

n
+
1

/

Z

(
2
,
1
,
…
,
1
)

\mathbb {Z}^{n+1}/\mathbb {Z}(2,1,\dots ,1)

. We then give a natural representation of the local Hecke algebra over

K
K

acting on the special vertices of the Bruhat-Tits building for

S

p
n

(
K
)

Sp_n(K)

. Finally, we give an application of the Hecke operators defined on the building by characterizing minimal walks on the building for

S

p
n

Sp_n

.
Cdc13 Telomere Capping Decreases Mec1 Association but Does Not Affect Tel1 Association with DNA Ends
Authors: Hirano Yukinori , Sugimoto Katsunori
Published: March 2007

Chromosome ends, known as telomeres, have to be distinguished from DNA breaks that activate DNA damage checkpoint. Two large protein kinases, ataxia-teleangiectasia mutated (ATM) and ATM-Rad3-related (ATR), control not only checkpoint activation but also telomere length. In budding yeast, Mec1 and Tel1 correspond to ATR and ATM, respectively. Here, we show that Cdc13-dependent telomere capping attenuates Mec1 association with DNA ends. The telomeric TG repeat sequence inhibits DNA degradation and decreases Mec1 accumulation at the DNA end. The TG-mediated degradation block requires binding of multiple Cdc13 proteins. The Mre11–Rad50-Xrs2 complex and Exo1 contribute to DNA degradation at DNA ends. Although the TG sequence impedes Exo1 association with DNA ends, it allows Mre11 association. Moreover, the TG sequence does not affect Tel1 association with the DNA end. Our results suggest that the Cdc13 telomere cap coordinates Mec1 and Tel1 accumulation rather than simply covering the DNA ends at telomeres.
5-Hydroxytryptamine4Receptor Activation of the Extracellular Signal-regulated Kinase Pathway Depends on Src Activation but Not on G Protein or β-Arrestin Signaling
Authors: Barthet Gaël , Framery Bérénice , Gaven Florence , Pellissier Lucie , Reiter Eric , Claeysen Sylvie , Bockaert Joël , Dumuis Aline
Published: March 2007

The 5-hydroxytryptamine4(5-HT4) receptors have recently emerged as key modulators of learning, memory, and cognitive processes. In neurons, 5-hydroxytryptamine4receptors (5-HT4Rs) activate cAMP production and protein kinase A (PKA); however, nothing is known about their ability to activate another key signaling pathway involved in learning and memory: the extracellular signal-regulated kinase (ERK) pathway. Here, we show that 5-HT4R stimulation, in primary neurons, produced a potent but transient activation of the ERK pathway. Surprisingly, this activation was mostly PKA independent. Similarly, using pharmacological, genetic, and molecular tools, we observed that 5-HT4Rs in human embryonic kidney 293 cells, activated the ERK pathway in a Gs/cAMP/PKA-independent manner. We also demonstrated that other classical G proteins (Gq/Gi/Go) and associated downstream messengers were not implicated in the 5-HT4R–activated ERK pathway. The 5-HT4R–mediated ERK activation seemed to be dependent on Src tyrosine kinase and yet totally independent of β-arrestin. Immunocytofluorescence revealed that ERK activation by 5-HT4R was restrained to the plasma membrane, whereas p-Src colocalized with the receptor and carried on even after endocytosis. This phenomenon may result from a tight interaction between 5-HT4R and p-Src detected by coimmunoprecipitation. Finally, we confirmed that the main route by which 5-HT4Rs activate ERKs in neurons was Src dependent. Thus, in addition to classical cAMP/PKA signaling pathways, 5-HT4Rs may use ERK pathways to control memory process.
Correlates of partial tooth loss and edentulism in the Brazilian elderly
Authors: Hugo Fernando Neves , Hilgert Juliana Balbinot , De Sousa Maria da Luz Rosário , Da Silva Débora Dias , Pucca Gilberto Alfredo
Published: March 2007

Abstract –  Background:  In South American older adults the association between tooth loss and demographic, predisposing and enabling factors has not been determined. The purpose of this study was to evaluate the association between partial and complete tooth loss and demographic, predisposing, enabling and need factors, and quality of life variables in the Brazilian older adults.

Methods:  In this cross‐sectional study, 5349 subjects aged 65–74 years were evaluated using conglomerate random sampling. Data collection included dental examinations and questionnaires evaluating demographic, predisposing, enabling and need factors, and quality of life variables. Multinomial logistic regression was carried out to evaluate correlates of tooth loss. The number of teeth was set as the outcome and categorized as: edentulous, subjects with 1–19 teeth, and subjects with 20 or more teeth.

Results:  Predisposing factors including age, female gender and schooling were independently associated with edentulism. Female gender was associated with partial tooth loss. The only enabling factor associated with edentulism was car ownership. Need factors were associated with edentulism and partial tooth loss. Edentulous subjects perceived the need for dental treatment less frequently. Quality of life factors were associated with partial tooth loss and edentulism. Subjects with 1–19 teeth and edentulous subjects were more likely to rate their chewing ability as not good. Edentulous subjects were more likely to rate their speech ability and their dental appearance as good.

Conclusions:  The results indicate that tooth loss and edentulism were complex phenomena, with intricate predisposing, demographic, enabling and need factors playing a role.
Nifedipine and cardiopulmonary bypass
Authors: CASSON W. R. , JONES R. M. , PARSONS R. S.
Published: March 2007

The management of the period after hypothermic cardiopulmonary bypass has been compared in a group of patients maintained on nifedipine therapy, a group who had the drug withdrawn at least 24 hours prior to cardiac surgery, and a control group who had never received calcium antagonists. Patients in the drug withdrawal group were significantly more likely to need vasodilator intervention than the treated (p < 0.001) or the control (p < 0.05) groups. Although nifedipine withdrawal appeared to reduce the need for inotropic support, compared to treated (p <0.001) and control groups (p <0.005), this may be at the cost of increasing systemic vascular resistance. This observation, coupled with reports of a rebound phenomenon following abrupt withdrawal of calcium antagonist therapy, suggests that nifedipine should be continued up to the time of surgery.
Comparison of atropine and glycopyrronium in patients with pre‐existing cardiac disease
Authors: MOSTAFA S. M. , VUCEVIC M.
Published: March 2007

The effects of atropine and glycopyrronium, when given intravenously with neostigmine during the reversal of neuromuscular blockade in patients with cardiovascular disease, were compared in a double blind trial. Atropine was associated with a significantly greater elevation of heart rate and rate‐pressure product than glycopyrronium. This elevation was also more sustained with atropine. The entire atropine population also showed a significantly greater incidence of ST‐segment depression on the electrocardiogram than that observed in those who had received glycopyrronium. Furthermore, patients with ischaemic heart disease and previous myocardial infarction who received atropine showed a significantly greater incidence of dysrhythmias than those given glycopyrronium. It is suggested that at the time of reversal of neuromuscular blockade in patients with cardiovascular disease, glycopyrronium is a more suitable agent than atropine.
The cerebral function analysing monitor Initial clinical experience, application and further development
Authors: MAYNARD D. E. , JENKINSON J. L.
Published: March 2007

The cerebral function analysing monitor is a development of the cerebral function monitor. It produces a more detailed analysis of the electroencephalogram (EEG) amplitude and analyses the frequency of the waveforms into standardbeta, alpha, thetaanddeltabands. It can analyse the EEG from two input channels, produce traces of the standard EEG, and compute visual, auditory, somato sensory and brain stem evoked potentials.
Anasthetic management of congenital fusion of the jaws in a neonate
Authors: SERAJ M. A. , YOUSIF M. , CHANNA A. B.
Published: March 2007

Fusion of the jaws in the neonate is a very rare congential anomaly which may be associated with other congenital defects such as aglossia, facial hemiatrophy or retrognathia. Ventilatory management for surgical separation of the fused jaws presents severe problems. In a recent case of a neonate with almost completely fused jaws requiring general anasthesia, we used subanasthetic doses of ketamine in combination with un insufflation technique. It took 45 minutes to reach the surgical stage of anasthesia due to misplacement of the nasotracheal tube through an unsuspected cleft palate towards a gap between the jaws, a previously unreported combination of complications.
A double‐blind comparison of nefopam and placebo used as a prernedication in children
Authors: Wilkinson P.A.
Published: March 2007

Forty‐two children received either nefopam or a maiched placebo as oral premedication in a double‐blind trial. Nefopam performed no better than placebo as a prernedication and as postoperative analgesic. Its use is not recommended in paediatric anasthesia because of a significanily high incidence of vomiting on awakening.