bluuebunny/crossref_metadata_2025 huggingface dataset:
Domain structures and piezoelectric properties in epitaxial Pb(Zr0.35,Ti0.65)O3 thin films
Authors: Kim Yong Kwan , Morioka Hitoshi , Ueno Risako , Yokoyama Shintaro , Funakubo Hiroshi , Lee Kilho , Baik Sunggi
Published: June 2006

The ferroelastic twin-domain structures and piezoelectric properties were investigated in epitaxial Pb(Zr0.35,Ti0.65)O3 thin films with various c-domain volume fractions by metal organic chemical vapor deposition on (100)cSrRuO3∕(100)SrTiO3 substrates. The domain structures could be characterized into three regions: a-domain dominant, c-domain dominant, and their mixed domain regions. The mixed domain structure is quite unusual but formed a bilayer with two regions of different a∕c domain proportions: the bottom layer is the a1-a2 domain structure and top layer is the a-c domain structure. The films of the mixed region have attained largest piezoelectric coefficients, d33, presumably due to enhanced a-to-c domain switching.
Design and performance of an optical fiber sensor based on light leakage
Authors: Golnabi H. , Jafari R.
Published: June 2006

Design and operation of an optical fiber sensor based on the light leakage from one fiber to another one causing intensity modulation are reported. Performance of this sensor is tested as a liquid level sensor for different liquids and the experimental results are reported. The dry and wet signals for this probe are measured for a series of measurements and important factors concerning sensor operation are described. The precision of measured values, reproducibility of the results (1.3%), and the stability of sensing operation as a function of time at different launching powers are also reported (0.8%). The reported results are promising and verify the successful operation of such a device as an on∕off level switch and also as a liquid level sensor.
Transnational Corporations and ‘Obligated Embeddedness’: Foreign Direct Investment in China's Automobile Industry
Authors: Liu Weidong , Dicken Peter
Published: June 2006

With the aid of an empirical case study of the automobile industry in China, we explore how, under certain political–economic conditions, the investments of transnational corporations (TNCs) can be shaped to meet the state's objectives. We develop the concept of ‘obligated embeddedness’ to capture the dynamics of this process. We show that foreign direct investment in the automobile industry in China is a type of market-led and embedded investment which is characterised by joint ventures and the follow-up network configurations. However, to achieve such obligated embeddedness on the part of TNCs—and for the state and its citizens to gain its benefits—the state not only has to have the theoretical capacity to control access to assets located within its territory, but also the power actually to determine such access.
From Software Services to R&D Services: Local Entrepreneurship in the Software Industry in Bangalore, India
Authors: Parthasarathy Balaji , Aoyama Yuko
Published: June 2006

In this paper we analyze the emergence of R&D services in Bangalore, India, by focusing on the process of technological upgrading in the Indian software industry. The development trajectory of the Indian software industry and the upgrading it has experienced, from providing low-skill software services to providing high-skill R&D services, are examined using evidence from interviews with Indian firms in Bangalore. Whereas most research on the Indian software industry thus far has emphasized the role of the state and multinational corporations, in this paper we argue that active local entrepreneurship is playing an increasingly important role in technological upgrading and in the shift from low-skill to high-skill services in Bangalore. These shifts are being facilitated by growing institutional thickness, as evidenced by the accumulation of local expertise, increasing local entrepreneurship addressing specific market niches, and the development of a local technical community.
Long-range cooperative binding effects in a T cell receptor variable domain
Authors: Moza Beenu , Buonpane Rebecca A. , Zhu Penny , Herfst Christine A. , Rahman A. K. M. Nur-ur , McCormick John K. , Kranz David M. , Sundberg Eric J.
Published: June 2006

Although cellular processes depend on protein–protein interactions, our understanding of molecular recognition between proteins remains far from comprehensive. Protein–protein interfaces are structural and energetic mosaics in which a subset of interfacial residues, called hot spots, contributes disproportionately to the affinity of the complex. These hot-spot residues can be further clustered into hot regions. It has been proposed that binding energetics between residues within a hot region are cooperative, whereas those between hot regions are strictly additive. If this idea held true for all protein–protein interactions, then energetically significant long-range conformational effects would be unlikely to occur. In the present study, we show cooperative binding energetics between distinct hot regions that are separated by >20 Å. Using combinatorial mutagenesis and surface plasmon resonance binding analysis to dissect additivity and cooperativity in a complex formed between a variable domain of a T cell receptor and a bacterial superantigen, we find that combinations of mutations from each of two hot regions exhibited significant cooperative energetics. Their connecting sequence is composed primarily of a single β-strand of the T cell receptor variable Ig domain, which has been observed to undergo a strand-switching event and does not form an integral part of the stabilizing core of this Ig domain. We propose that these cooperative effects are propagated through a dynamic structural network. Cooperativity between hot regions has significant implications for the prediction and inhibition of protein–protein interactions.
How photosynthetic reaction centers control oxidation power in chlorophyll pairs P680, P700, and P870
Authors: Ishikita Hiroshi , Saenger Wolfram , Biesiadka Jacek , Loll Bernhard , Knapp Ernst-Walter
Published: June 2006

At the heart of photosynthetic reaction centers (RCs) are pairs of chlorophyll
a
(Chl
a
), P700 in photosystem I (PSI) and P680 in photosystem II (PSII) of cyanobacteria, algae, or plants, and a pair of bacteriochlorophyll
a
(BChl
a
), P870 in purple bacterial RCs (PbRCs). These pairs differ greatly in their redox potentials for one-electron oxidation,
E
m
. For P680,
E
m
is 1,100–1,200 mV, but for P700 and P870,
E
m
is only 500 mV. Calculations with the linearized Poisson–Boltzmann equation reproduce these measured
E
m
differences successfully. Analyzing the origin for these differences, we found as major factors in PSII the unique Mn
4
Ca cluster (relative to PSI and PbRC), the position of P680 close to the luminal edge of transmembrane α-helix d (relative to PSI), local variations in the cd loop (relative to PbRC), and the intrinsically higher
E
m
of Chl
a
compared with BChl
a
(relative to PbRC).
Loss of
Aif
function causes cell death in the mouse embryo, but the temporal progression of patterning is normal
Authors: Brown Doris , Yu Benjamin D. , Joza Nicholas , Bénit Paule , Meneses Juanito , Firpo Meri , Rustin Pierre , Penninger Josef M. , Martin Gail R.
Published: June 2006

Apoptosis-inducing factor (AIF) is an evolutionarily conserved, ubiquitously expressed flavoprotein with NADH oxidase activity that is normally confined to mitochondria. In mammalian cells, AIF is released from mitochondria in response to apoptotic stimuli and translocates to the nucleus where it is thought to bind DNA and contribute to chromatinolysis and cell death in a caspase-independent manner. Here we describe the consequences of inactivating
Aif
in the early mouse embryo. Unexpectedly, we found that both the apoptosis-dependent process of cavitation in embryoid bodies and apoptosis associated with embryonic neural tube closure occur in the absence of AIF, indicating that
Aif
function is not required for apoptotic cell death in early mouse embryos. By embryonic day 9 (E9), loss of
Aif
function causes abnormal cell death, presumably because of reduced mitochondrial respiratory chain complex I activity. Because of this cell death,
Aif
null embryos fail to increase significantly in size after E9. Remarkably, patterning processes continue on an essentially normal schedule, such that E10
Aif
null embryos with only ≈1/10 the normal number of cells have the same somite number as their wild-type littermates. These observations show that pattern formation in the mouse can occur independent of embryo size and cell number.
A mechanism of cell death involving an adenylyl cyclase/PKA signaling pathway is induced by the Cry1Ab toxin of
Bacillus thuringiensis
Authors: Zhang Xuebin , Candas Mehmet , Griko Natalya B. , Taussig Ronald , Bulla Lee A.
Published: June 2006

Many pathogenic organisms and their toxins target host cell receptors, the consequence of which is altered signaling events that lead to aberrant activity or cell death. A significant body of literature describes various molecular and cellular aspects of toxins associated with bacterial invasion, colonization, and host cell disruption. However, there is little information on the molecular and cellular mechanisms associated with the insecticidal action of
Bacillus thuringiensis
(Bt) Cry toxins. Recently, we reported that the Cry1Ab toxin produced by Bt kills insect cells by activating a Mg
2+
-dependent cytotoxic event upon binding of the toxin to its receptor BT-R
1
. Here we show that binding of Cry toxin to BT-R
1
provokes cell death by activating a previously undescribed signaling pathway involving stimulation of G protein (G
αs
) and adenylyl cyclase, increased cAMP levels, and activation of protein kinase A. Induction of the adenylyl cyclase/protein kinase A pathway is manifested by sequential cytological changes that include membrane blebbing, appearance of ghost nuclei, cell swelling, and lysis. The discovery of a toxin-induced cell death pathway specifically linked to BT-R
1
in insect cells should provide insights into how insects evolve resistance to Bt and into the development of new, safer insecticides.
TSSub: eukaryotic protein subcellular localization by extracting features from profiles
Authors: Guo Jian , Lin Yuanlie
Published: June 2006

Summary: This paper introduces a new subcellular localization system (TSSub) for eukaryotic proteins. This system extracts features from both profiles and amino acid sequences. Four different features are extracted from profiles by four probabilistic neural network (PNN) classifiers, respectively (the amino acid composition from whole profiles; the amino acid composition from the N-terminus of profiles; the dipeptide composition from whole profiles and the amino acid composition from fragments of profiles). In addition, a support vector machine (SVM) classifier is added to implement the residue-couple feature extracted from amino acid sequences. The results from the five classifiers are fused by an additional SVM classifier. The overall accuracies of this TSSub reach 93.0 and 77.4% on Reinhardt and Hubbard's eukaryotic protein dataset and Huang and Li's eukaryotic protein dataset, respectively. The comparison with existing methods results shows TSSub provides better prediction performance than existing methods.

Availability: The web server is available from

Contact:  guojian99@tsinghua.org.cn

Supplementary Information: The Supplementary Data can be downloaded from
HCNet: a database of heart and calcium functional network
Authors: Hong Seong-Eui , Rho Seong-Hwan , Yeom Young Il , Kim Do Han
Published: June 2006

Summary: The Heart and Calcium functional Network (HCNet) database is a collection of functional gene modules calculated from the microarray data compendium available from the GEO database. It is a specialized database designed to assist experimentalists for cardiac calcium signaling research by providing the pre-calculated gene clusters and their potential correlation network in heart.

In the current release of HCNet, 57 functional modules from 786 target genes obtained by a bi-clustering analysis of 381 microarray datasets are available. Detailed information of the clusters such as expression profiles, network diagrams is provided in two categories, heart-specific genes and heart-specific genes along with calcium toolkit genes. Overrepresented gene ontological categories and transcription factors in each cluster are also provided to infer the biological implications of the detected functional modules.

Availability: HCNet is available at

Contact:  dhkim@gist.ac.kr
High level of cryptic species diversity revealed by sympatric lineages of Southeast Asian forest frogs
Authors: Stuart Bryan L , Inger Robert F , Voris Harold K
Published: June 2006

Amphibians tend to exhibit conservative morphological evolution, and the application of molecular and bioacoustic tools in systematic studies have been effective at revealing morphologically ‘cryptic’ species within taxa that were previously considered to be a single species. We report molecular genetic findings on two forest-dwelling ranid frogs from localities across Southeast Asia, and show that sympatric evolutionary lineages of morphologically cryptic frogs are a common pattern. These findings imply that species diversity of Southeast Asian frogs remains significantly underestimated, and taken in concert with other molecular investigations, suggest there may not be any geographically widespread, forest-dwelling frog species in the region. Accurate assessments of diversity and distributions are needed to mitigate extinctions of evolutionary lineages in these threatened vertebrates.
Levels of linkage disequilibrium in a wild bird population
Authors: Backström Niclas , Qvarnström Anna , Gustafsson Lars , Ellegren Hans
Published: June 2006

Population-based mapping approaches are attractive for tracing the genetic background to phenotypic traits in wild species, given that it is often difficult to gather extensive and well-defined pedigrees needed for quantitative trait locus analysis. However, the feasibility of association or hitch-hiking mapping is dependent on the degree of linkage disequilibrium (LD) in the population, on which there is yet limited information for wild species. Here we use single nucleotide polymorphism (SNP) markers from 23 genes in a recently established linkage map of the Z chromosome of the collared flycatcher, to study the extent of LD in a natural bird population. In most but not all cases we find SNPs within the same intron (less than 500 bp) to be in perfect LD. However, LD then decays to background level at a distance 1 cM or 400–500 kb. Although LD seems more extensive than in other species, if the observed pattern is representative for other regions of the genome and turns out to be a general feature of natural bird populations, dense marker maps might be needed for genome scans aimed at identifying association between marker and trait loci.
Electric field gradient effects in an anti-plane circular inclusion in polarized ceramics
Authors: Yang J.S , Zhou H.G , Li J.Y
Published: June 2006

We analyse electric field gradient (or quadrupole) effects in the anti-plane problem of a small, circular inclusion in polarized ceramics. An exact solution is obtained. The solutions show that, different from the classical inclusion solution from the linear theory of piezoelectricity, the electric field in the inclusion is no longer uniform. This has implications in field concentration and strength considerations and the prediction of effective material properties of composites.
A method for dating early books and prints using image analysis
Authors: Blair Hedges S
Published: June 2006

Many books and works of art printed over the centuries by hand-operated presses are undated or poorly dated. The use of classical methods of dating, such as matching watermarks in paper, has had limited success. Here, evidence is presented that the woodblocks and metal plates used in printing deteriorated at a constant rate, useful for time estimation. This change was measured in 2674 Renaissance prints. In successive editions, woodblock prints increased in the number of line breaks, whereas copperplate prints became paler. In both cases, the change was time dependent, not print dependent. For woodblocks, this can be explained by the aging of the wood, creating breaks in lines. For copperplates, image fading is a result of line thinning caused by surface erosion of the plate, not from compression by the printing press. The time dependency in copperplates is best explained by corrosion during plate storage, which was removed before each printing by polishing (erosion). The average rate of copperplate deterioration, 1–2 μm yr
−1
, was estimated from the thinning rates of lines in two Italian prints and agrees with typical rates of atmospheric corrosion of copper. The print clock, if it applies generally, offers a relatively simple means of dating early books and prints.
Are there differences in immune function between continental and insular birds?
Authors: Matson Kevin D
Published: June 2006

Generally, immune system architecture varies with different environments, which presumably reflect different pathogen pressures. Specifically, populations from relatively disease-free, oceanic islands are expected to exhibit reorganized immune systems, which might be characterized by attenuated responses, given the costs of immune function. Some insular animals exhibit an ‘island syndrome,’ including increased susceptibility to disease, and some insular populations have declined when they failed to resist infection by introduced pathogens. I measured eight indices of immune function (haemolysis, haemagglutination, concentration of haptoglobin and concentration of five leukocyte types) in 15 phylogenetically matched pairs of bird populations from North America and from the islands of Hawaii, Bermuda and the Galápagos. Immune responses were not attenuated in insular birds, and several indices, including the concentration of plasma haptoglobin, were elevated. Thus, I find no support for the specific hypothesis that depauperate parasite communities and the costs of immune defences select for reduced immune function. Instead, I suggest that life on islands leads to an apparent reorganization of immune function, which is defined by increases in defences that are innate and inducible. These increases might signal that systems of acquired humoral immunity and immunological memory are less important or dysfunctional in island populations.
Mother guarding: how offspring may influence the extra-pair behaviour of their parents
Authors: Welbergen Justin A , Quader Suhel
Published: June 2006

In this paper we propose a novel form of social control of mate choice. Through mother guarding, offspring can help in protecting the paternity of their father by preventing their mother from engaging in extra-pair matings. We present a model that predicts the circumstances under which mothers should be selected to seek or avoid extra-pair matings, and existing offspring should be selected to prevent or promote such matings. In its simplest form, our model shows that offspring are selected to mother guard as long as the viability of extra-pair young is less than twice that of within-pair young; when the relative viability is greater, offspring are selected to promote extra-pair mating by their mother. If the existing offspring are not necessarily sired by their mother's social mate, then the potential for conflict is further reduced. We also consider whether offspring have an interest in the extra-pair reproduction of their fathers. We show that when the costs of the father's infidelity to the mother's brood are high, existing offspring are selected to prevent extra-pair mating by their father; when such costs are low, offspring are selected to promote extra-pair mating by their father. In principle, our model applies to all species where offspring show delayed dispersal and where breeding pairs raise multiple broods or litters. This situation exists in, but is not limited to, the majority of cooperatively breeding species. The significance of this model with regard to our current understanding of the evolution of extra-pair behaviour in such species is discussed.
Integrative capacity of the caudal brainstem in the control of food intake
Authors: Schwartz Gary J
Published: June 2006

The caudal brainstem nucleus of the solitary tract (NTS) is the initial central nervous system (CNS) terminus for a variety of gastrointestinal mechanical, nutrient chemical and gut peptide signals that limit the amount of food consumed during a meal. It receives neuroanatomical projections from gut vagal and non-vagal visceral afferents that mediate the CNS representation of these meal-stimulated gut feedback signals, and is reciprocally connected to a range of hypothalamic and limbic system sites that play significant roles in the neural processing of meal-related stimuli and in determining food consumption. Neurons in the NTS also contains elements of leptinergic and melanocortinergic signalling systems, presenting the possibility that the brainstem actions of these neuropeptides affect both the NTS processing of meal-stimulated gut afferent neural activity and its behavioural potency. Taken together, these features suggest that the NTS is ideally situated to integrate central and peripheral signals that determine meal size. This manuscript will review recent support from molecular genetic, neurophysiological and immunocytochemical studies that begin to identify and characterize the types of integrative functions performed within the NTS, and highlight the extent to which they are consistent with a causal role for NTS integration of peripheral gut and central neuropeptide signals important in the control of food intake.
Contrasting functional traits maintain lichen epiphyte diversity in response to climate and autogenic succession
Authors: Ellis Christopher J. , Coppins Brian J.
Published: June 2006

Aim  Lichen epiphytes are important for biodiversity conservation and are also widely applied as environmental indicators. However, biogeographical and ecological knowledge underpinning lichen epiphyte conservation, and the use of lichens as indicators, is based primarily on a limited range of ‘macrolichen’ species. Wider trends in epiphyte biodiversity remain largely unexplored. This paper examines the community structure of lichen epiphytes on aspen (Populus tremula L.) in Scotland, including species across all functional groups and comprising, therefore, taxonomically difficult ‘microlichens’.

Location  Northern Britain (Scotland).

Methods  Epiphytes were sampled from 12 sites throughout Scotland and examined at two scales: between and within aspen stands. Species were classified into contrasting functional groups and ordination by detrended correspondence analysis was used to summarize community structure.

Results  Within aspen stands (between trees) epiphyte communities showed successional patterns related to tree age. These successional patterns changed predictably for stands aligned along a climatic gradient (between stands).

Main conclusions  A dual climatic–successional trend in epiphyte community structure is presented. Large‐scale trends in epiphyte diversity are explained as the local response of species with contrasting functional traits to climate and autogenic succession. Turnover of functional groups between stands is positively related to β‐diversity, and ecological limits to the frequency of contrasting functional groups are presented. Accordingly, the study and application of lichen species with similar functional traits may inadequately represent patterns of biodiversity. This prompts criticism of the currently accepted conservation strategy, i.e. (1) an emphasis in the conservation literature on ‘macrolichen’ species with similar ecologies and (2) the application of lichen indices over climatically variable geographical areas.
The generality of the island rule reexamined
Authors: Meiri Shai , Dayan Tamar , Simberloff Daniel
Published: June 2006

Aim  M.V. Lomolino and colleagues have recently reviewed the island rule in mammals and other vertebrates, claiming it is a general pattern. They have portrayed our recent analysis as weakly supporting the island rule, seeing weakness in our use of what they considered to be inadequate size indices (skulls and teeth, rather than mass or body length) and in our use of large islands. They argue that size evolution on islands points to a bauplan‐specific fundamental size. We aim to test the generality of the rule and the adequacy of some of the data used to support it.

Location  Insular environments world‐wide.

Methods  We collate and analyse data on skull sizes of carnivores and body masses of mammals in general to see whether there is a graded trend from dwarfism in large species to gigantism in smaller ones.

Results  The island rule is not supported with either the carnivore or the mammal data sets. Island area does not influence size change.

Main conclusions  Our results suggest that data recently advanced in support of the island rule are inadequate and that the island rule is not a general pattern for all mammals.
Assessing the origin of Neotropical mountain dung beetle assemblages (Scarabaeidae: Scarabaeinae): the comparative influence of vertical and horizontal colonization
Authors: Escobar Federico , Lobo Jorge M. , Halffter Gonzalo
Published: June 2006

Aims  The fauna of mountains and their surrounding regions are likely to be influenced principally by two biological processes: horizontal colonization along similar altitudinal levels by elements originating from lineages inhabiting higher latitudes; and vertical colonization by lineages from the same latitude, but at lower altitudes. We examine whether the expected patterns derived from the latter process can be observed in mountain dung beetle assemblages. Specifically, we study the variation in species composition and richness with altitude in five regions spanning elevation gradients, analysing whether the altitudinal rates of change in the number of species and genera differ, and whether beta‐diversity scores for adjacent sites in each altitudinal gradient are different for species and genera.

Location  Eastern Cordillera of the Colombian Andes.

Methods  Field work was carried out in 1997–99 at 27 sites in five regions with elevation gradients, with 10–32 pitfall traps placed in each site. For each altitudinal level the numbers of species and genera were analysed with respect to altitude, and the slope of the linear regression between these variables was calculated. The slope of the curve of the altitude against the cumulative number of species and genera was also calculated for each altitudinal gradient to describe the compositional change between adjacent sites (beta diversity). Species and generic slopes were compared using analysis of covariance. The turnover of species along each altitudinal gradient was measured using presence/absence data and Cody's beta‐diversity index between adjacent pairs of sites. A cluster analysis was used to detect faunistically homogeneous groups of localities.

Results  Species richness always decreased with altitude, although the slopes did not differ significantly from zero. The number of genera also decreased with increasing altitude, but generally at a significantly slower rate than for species. Variation in the species beta‐diversity scores between altitudinal levels did not follow a homogeneous pattern in the different regions. Two main altitudinal groups of sites with a boundary c. 1500–1750 m a.s.l. can be detected with respect to faunistic similarity. Low‐ and mid‐altitude sites are inhabited by all of the genera (19) and 80% of all species collected. Eight genera and 61 species (c. 60% of the total) are unable to inhabit high‐altitude sites, and only 20 species appear to be exclusive to these high‐altitude environments (> 2000 m a.s.l.).

Main conclusions  The dominant processes explaining dung beetle composition in the high north‐eastern Andean mountains are probably those of vertical colonization. The limited role of horizontal colonization processes, or colonization from northern or southern lineages, could be a consequence of the isolation and recent geological origin of these mountains.
Influences of infrequent fire, elevation and pre‐fire vegetation on the persistence of quaking aspen (Populus tremuloidesMichx.) in the Flat Tops area, Colorado, USA
Authors: Kulakowski Dominik , Veblen Thomas T. , Kurzel Brian P.
Published: June 2006

Aim The recent concern that quaking aspen (Populus tremuloidesMichx.) has been declining in parts of western North America due to fire suppression is largely based on trends during the latter part of the 20th century. The aim of the current study was to compare the extent of aspen in the modern landscape with its extent in the late 19th century prior to fire suppression, and to assess the effects of elevation, late‐19th century fires, and pre‐fire forest composition on the successional status of aspen.

Location North‐west Colorado, USA.

Methods We used a georeferenced 1898 map and modern maps to examine trends in aspen dominance since the late 19th century in a 348,586 ha area of White River and Routt National Forests in north‐western Colorado. Stand age and structure were sampled in 30 stands.

Results We found no evidence of overall aspen decline over this period. In fact, aspen distribution has increased in parts of the study area following severe fires in the late 19th century in forests that were previously dominated by conifers. Aspen persistence and increase was especially pronounced at elevations below 3000 m a.s.l. Most 120‐year‐old post‐fire stands that are presently being successionally replaced by conifers were dominated by conifers prior to the last severe fire.

Main conclusions Human perceptions of ecosystems are often on time scales that are shorter than the cycles of natural variation within those ecosystems. This disparity may lead to an underestimation of the range of natural variability of ecosystem patterns and processes. The appropriate temporal scale of inquiry is necessary for the correct understanding of natural variation in ecosystems.
Extracellular signal‐regulated protein kinase is activated in cervical intraepithelial neoplasms but inactivated in invasive cervical carcinoma
Authors: Matsuura Keiko , Nohno Yuka , Hijiya Naoki , Uchida Tomohisa , Tsukamoto Yoshiyuki , Moriyama Masatsugu
Published: June 2006

The extracellular signal‐regulated protein kinase (ERK) signaling pathway has been reported to play important roles in cell growth in various neoplasms. The purpose of the present study was to immunohistochemically analyze the phosphorylation status (activity) of ERK in 24 cases of cervical carcinoma using an antiphosphorylated ERK antibody (αp‐ERK Ab) that specifically recognizes the phosphorylated form of ERK (p‐ERK). In normal cervical epithelium, p‐ERK was found to be confined to basal cells that were negative for Ki‐67, suggesting that ERK was not activated in proliferating normal cervical epithelium. In cervical intraepithelial neoplasms (CIN), increased abnormal parabasal cells were positive for both p‐ERK and Ki‐67, suggesting that ERK activation in CIN may be involved in tumor cell proliferation. In contrast, it was found that, in invasive cervical carcinomas, almost all the carcinoma cells were positive for Ki‐67 but negative for p‐ERK, suggesting that, in contrast to many other types of cancers, the ERK signaling pathway is downregulated in invasive cervical carcinoma. These findings suggest that the phosphorylation status of ERK differs between CIN and invasive carcinomas, and that downregulation of the ERK signaling pathway may contribute to transformation of CIN to invasive cervical carcinomas.
Determination of global failure pressure for tubes with two parallel cracks
Authors: MOON S.‐I. , CHANG Y.‐S. , KIM Y.‐J. , LEE J.‐H. , SONG M.‐H , CHOI Y.‐H. , KIM J.‐S.
Published: June 2006

The 40% of wall thickness criterion, which has been used as a plugging rule is applicable only to a single cracked steam generator tubes. In the previous studies performed by the authors, several failure prediction models were introduced to estimate the plastic collapse pressures of steam generator tubes containing two adjacent parallel axial through‐wall cracks. These models were applied preliminarily for thin plates with two parallel through‐wall cracks and the crack opening displacement (COD) base model was selected as the optimum one. The objective of this study is to verify the applicability of the proposed failure prediction model for real steam generator tubes with two parallel axial through‐wall cracks. For this purpose, a series of plastic collapse tests and finite element analyses have been carried out for the steam generator tubes with two machined parallel axial through‐wall cracks. Thereby, it was proven that the proposed failure prediction model can be used for estimating the global failure pressure quite well. Also, interaction effects between two adjacent cracks were assessed through additional finite element analyses to investigate the effect on the global failure behaviour.
A combined experimental‐numerical investigation of crack growth in a carbon–carbon composite
Authors: HAN J. , SIEGMUND T.
Published: June 2006

A combined experimental–numerical investigation of crack growth in a carbon–carbon composite is reported. In this material, both matrix fracture and fibre bridging contribute significantly to toughness. Crack growth experiments were performed using side‐notched DCB specimens with doublers. A digital image correlation method was used to measure displacements fields on the specimen surfaces, crack extension and crack opening profiles. An effective cohesive zone law was determined from the experimental data. The effective cohesive zone law is subsequently separated into the individual contributions from matrix cracking and fibre bridging. Numerical simulation of crack growth based on this cohesive zone law and experimental data are in good agreement. Special focus of the numerical study is on the investigation of the discontinuous nature of crack growth.
Towards a new Bradshaw? Economic statistics and the British state in the 1950s and 1960s
Authors: O’HARA GLEN
Published: June 2006

This article outlines the attempts of British central government to react to the perceived inadequacy of official economic statistics. A huge amount of work went into this project, the main aim of which was to speed up the production of statistics so that the economy could be analysed in more detail, and thus better managed. If this was to work, more data was required on the labour market, on productivity, on production, and on the interlinkages between those indicators. British official statistics clearly were more comprehensive and more detailed at the end of this period than they had been at the start. Even so, the effort was usually thought to have been a failure by the early 1970s. More detail took time to produce; it was difficult to recruit the necessary staff; successive administrative reorganizations also absorbed energies. The devolved informality of British government hampered the emergence of an overall picture. Businesses and trade unions resisted attempts to collect more data, especially when it showed them in an unflattering light. Above all, the elite, specialist, and technical nature of the reform process meant that very little political and popular pressure built up to force through further changes.
Age‐related effects of the neuromodulator d‐serine on neurotransmission and synaptic potentiation in the CA1 hippocampal area of the rat
Authors: Junjaud G. , Rouaud E. , Turpin F. , Mothet J.‐P. , Billard J.‐M.
Published: June 2006

The effects of the co‐agonist of the N‐methyl‐d‐aspartate receptor (NMDAr) d‐serine on glutamatergic neurotransmission and synaptic potentiation were studied in the CA1 hippocampal field of young (3–5 months old) and aged (25–27 months old) Sprague–Dawley rats using ex vivo extracellular electrophysiological recording techniques. Exogenous d‐serine depressed fast neurotransmission mediated by the α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid/kainate subtype of glutamate receptors in young but not in aged rats by acting on inhibitory glycinergic interneurons. In contrast, d‐serine dose‐dependently enhanced NMDAr‐mediated synaptic responses in both groups of animals, but with a larger magnitude in aged rats, thus preventing the age‐related decrease in NMDAr activation. d‐serine also increased the magnitude of long‐term potentiation in aged but not in young rats. Finally, d‐serine levels were dramatically reduced in hippocampal tissues of aged rats. Taken together, these results indicate a weaker activation of the NMDAr glycine modulatory site by endogenous d‐serine in aged animals, which accounts for a reduced NMDAr contribution to synaptic plasticity in ageing.
The exponential‐mean‐log‐transference as a possible representation of the optical character of an average eye
Authors: Harris W. F. , Cardoso J. R.
Published: June 2006

Considering a set of eyes, how does one define an average whose optical character represents an average of the optical characters of the eyes in the set? The recent proposal of the exponential‐mean‐log‐transference was based on a conjecture. The purpose of this note is to provide justification by proving the conjecture and defining the conditions under which it fails.
Converting principal meridional representation of power to the coordinates of the power matrix using the matrix similarity transform
Authors: Abelman H.
Published: June 2006

General or local variations of the refractive elements in the eye, called irregular astigmatism, may manifest as non‐orthogonal meridians when each principal meridian on the front surface of a cornea is independently aligned with the focussed mires of a keratometer. These are examples of astigmatic systems that are thick. The representation of power along the principal meridians is not suitable for quantitative work. The purpose of this research note is to convert power along principal meridians that can be non‐orthogonal, to the coordinates of the power matrix that are suitable for quantitative analysis.
Non‐contact tonometry synchronized with cardiac rhythm and its relationship with blood pressure
Authors: Queirós A. , González‐Méijome J. M. , Fernandes P. , Jorge J. , Almeida J. B. , Parafita M. A.
Published: June 2006

Purpose:  The main objectives of this study were to determine the differences between non‐synchronized intraocular pressure (IOP_N) and intraocular pressure readings synchronized with cardiac pulse and try to determine if these parameters are related to blood pressure values.

Methods:  One hundred and sixty‐five right eyes from 165 volunteers (107 females, 58 males) aged from 19 to 73 years (mean ± S.D., 29.93 ± 11.17) were examined with the Nidek NT‐4000, a new non‐contact tonometer that allows the measurement of IOP synchronized with the cardiac rhythm. IOP measurements in the four different modes of synchronization were taken in a randomized order. Three measures of each parameter were taken and then averaged. The blood pressure was determined three times with a portable manometer and mean values of systolic and diastolic pressure and the pulse rate were computed. Mean arterial pressure (MAP) was determined as being 1/3 of systolic plus 2/3 of diastolic blood pressure.

Results:  The mean ± S.D. values for the standard intraocular pressure (IOP_N: 14.76 ± 2.86), intraocular pressure in the systolic instant or peak (IOP_P: 14.99 ± 2.85), intraocular pressure in the middle instant between heartbeats or middle (IOP_M: 14.68 ± 2.76), and intraocular pressure in the diastolic instant or bottom (IOP_B: 13.86 ± 2.61) were obtained. The IOP_P was higher than the remaining values. A significant difference in mean IOP existed between IOP_B and the remaining modes of measuring (p < 0.05). Differences were statistically significant for all pair comparisons involving IOP_B. Arterial blood pressure values were systolic 125.5 ± 14.22, diastolic 77.7 ± 8.38 and MAP 93.64 ± 9.44 mmHg. The pulse rate was 77.3 ± 12.6 beats per minute. Except for the MAP (p = 0.025) there was no significant correlation between different IOP values and systolic or diastolic blood pressure, or pulse rate.

Conclusions:  NT‐4000 is able to differentiate IOP values when synchronized with the cardiac rhythm and those differences are expected to be within a range of ±2.5 to ± 3.0 mmHg. IOP_B seems to be the parameter whose value differs from the non‐synchronized and the remaining synchronized parameters in a significant way. Other than a weak association with MAP, no significant correlation between IOP and BP was found. The measurements of IOP readings for the three modes are consistent with timings during the cardiac cycle and IOP pulse cycle.
Supplementation with the carotenoids lutein or zeaxanthin improves human visual performance
Authors: Kvansakul Jessica , Rodriguez‐Carmona Marisa , Edgar David F. , Barker Felix M. , Köpcke Wolfgang , Schalch Wolfgang , Barbur John L.
Published: June 2006

Background:  Macular pigment (MP) is found in diurnal primate species when vision spans a range of ambient illumination and is mediated by cone and rod photoreceptors. The exact role of MP remains to be determined. In this study we investigate two new hypotheses for possible MP functions.

Objective:  As MP absorption coincides partly with that of rhodopsin, MP may reduce rod signal effectiveness in the mesopic range, thus extend the usefulness of cone‐mediated vision into the mesopic range. Forward light scatter in the eye can reduce retinal image contrast. If blue light contributes significantly to intraocular scatter, selective blue light absorption by MP could reduce the effects of scatter.

Design:  We investigated 34 subjects from a carotenoid supplementation trial. The measurements included high mesopic contrast acuity thresholds (CATs), macular pigment optical density (MPOD), wavefront aberrations, and scattered light. The measurements were made after 6 months of daily supplementation with zeaxanthin (Z, OPTISHARP™), lutein (L), a combination of the two (C), or placebo (P), and again after a further 6 months of doubled supplementation.

Results:  The data reveal a trend toward lower CATs in all groups supplemented, with a statistically significant improvement in the lutein group (p = 0.001), although there was no correlation with MPOD. Light scattering in the eye and the root‐mean‐square wavefront aberrations show decreasing trends as a result of supplementation, but no correlation with MPOD.

Conclusions:  The results suggest that supplementation with L or Z increases MPOD at the fovea and at 2.5°, and that supplementation can improve CATs at high mesopic levels and hence visual performance at low illumination.
A simple new method for the construction of a ptosis crutch
Authors: Walsh Glyn , Rafferty Peter R. M. , Lapin John
Published: June 2006

A technique by which a ptosis crutch can be fitted in minutes, using readily available and inexpensive materials and tools, is described. No specialist skills are needed and the device can be fitted to existing frames and lenses.
Dynamics of ocular surface topography in healthy subjects
Authors: Erdélyi Béla , Csákány Béla , Rödönyi Gábor , Soumelidis Alexandros , Lang Zsolt , Németh János
Published: June 2006

Our topography system is an enhancement of a standard TMS‐1 corneal topograph instrument (Computed Anatomy Inc., New York, NY, USA). Topographic images are captured at a rate of 4 s−1, allowing the recording of a series of 120 images in 30 s after a complete blink. In this prospective preliminary study 15 healthy volunteers were examined. The main outcome measures were the time profile of changes in surface regularity index (SRI), surface asymmetry index (SAI) and simulated keratometry values (K1, K2). After a blink there was a tendency for improvement in ocular surface regularity. Later trends were less clear. Our topography system makes possible the detailed evaluation of tear‐film dynamics in the post‐blink period. The new technique may play an important role in the diagnosis of various tear‐film abnormalities; the results may also have significant implications in the planning of refractive surgeries.
Fusidic acid viscous eyedrops – an evaluation of pharmacodynamics, pharmacokinetics and clinical use for UK optometrists
Authors: Doughty Michael J. , Dutton Gordon N.
Published: June 2006

Recent changes in UK law have allowed UK‐based optometrists to sell and supply fusidic acid viscous eyedrops, providing it is in the course of their professional activity and in an emergency. Alternatively, the optometrist may access fusidic acid viscous eyedrops, for a named patient, using a written order supplied to a pharmacy. This review provides details of the legal background to these changes, examines the common causes of a bacterial conjunctivitis, examines the mechanism of action of this narrow spectrum antibiotic as a bacteriostatic agent, reviews the susceptibility of common ocular isolates of bacteria to the drug and presents details of the expected pharmacokinetics of the viscous eyedrops. From this perspective, a systematic review is provided of the clinical studies which have investigated the use of fusidic acid viscous eyedrops and their outcome. The indicated use is generally for the treatment of bacterial conjunctivitis and/or blepharoconjunctivitis, especially that caused by Staphylococcus, but not Streptococcus or Haemophilus sp. (more likely associated with concurrent nasopharyngeal infections). The usual regimen for use is twice daily for 5–10 days, depending on severity, and can initially be used more intensively (four times per day). It may also be used for the management of corneal and conjunctival abrasions and foreign body injuries, or some cases of chronic blepharitis.
Characterization of polymetamorphism in the Austroalpine basement east of the Tauern Window using garnet isopleth thermobarometry
Authors: GAIDIES F. , ABART R. , DE CAPITANI C. , SCHUSTER R. , CONNOLLY J. A. D. , REUSSER E.
Published: June 2006

Garnet in metapelites from the Wölz and Rappold Complexes of the Austroalpine basement east of the Tauern Window typically shows two distinct growth zones. A first garnet generation usually forms the cores of garnet porphyroblasts and is separated by a prominent microstructural and chemical discontinuity from a second garnet generation, which forms rims of variable width. Whereas the rims were formed during the Eo‐Alpine metamorphic overprint, the garnet cores represent remnants of at least two pre‐Eo‐Alpine metamorphic events. The pressure and temperature estimates obtained from garnet isopleth thermobarometry applied to the first growth increments of the pre‐Eo‐Alpine garnet cores from the Wölz and Rappold Complexes cluster into two distinct domains: (i) in the Wölz Complex, incipient growth of the first‐generation garnet occurred at 4 ± 0.5 kbar and 535 ± 20 °C, (ii) in the Rappold Complex, incipient growth of the oldest garnet cores took place at 5.3 ± 0.3 kbar and 525 ± 15 °C. The Eo‐Alpine garnet generation started to grow at 6.5 ± 0.5 kbar and 540 ± 10 °C. According to radiometric dating, the low‐pressure garnet from the Wölz complex was formed during a Permian metamorphic event. The first‐generation garnet of the Rappold Complex is probably of Variscan age.