bluuebunny/crossref_metadata_2025 huggingface dataset:
Similarities and differences in mothers’ parenting of preschoolers in China and the United States
Authors: Wu Peixia , Robinson Clyde C. , Yang Chongming , Hart Craig H. , Olsen Susanne F. , Porter Christin L. , Jin Shenghua , Wo Jianzhong , Wu Xinzi
Published: October 2002

This investigation was designed to extend the work of Chao (1994) by examining parenting constructs emphasised in the Chinese culture in conjunction with parenting constructs derived and emphasised in North America. Mothers of preschool-age children from mainland China ( N = 284) and the United States ( N = 237) completed two self-report parenting questionnaires. One assessed dimensions of parenting practices emphasised in China (encouragement of modesty, protection, directiveness, shaming/love withdrawal, and maternal involvement). The second measured specific stylistic dimensions within Baumrind’s global conceptualisations of authoritative (warmth/acceptance, reasoning/induction, democratic participation) and authoritarian (physical coercion, verbal hostility, nonreasoning/punitive) parenting. Mostly invariant factor structures were obtained across cultures for both measures. Results showed that the five parenting constructs emphasised in China were mostly nonoverlapping and independent in both cultures. In addition, the parenting constructs emphasised in China were relatively independent from the constructs emphasised in North America. As anticipated, Chinese mothers scored higher than US mothers on all parenting constructs emphasised in China except maternal involvement. For parenting constructs emphasised in North America, Chinese mothers scored lower than US mothers on warmth/acceptance and democratic participation, but scored higher on physical coercion.
Sex differences in syntactic development: Evidence from Cantonese-speaking preschoolers in Hong Kong
Authors: Tse Shek Kam , Chan Carol , Kwong Sin Mee , Li Hui
Published: October 2002

Utterances produced during spontaneous play activities by 180 Cantonese-speaking children, ranging in age from 3 to 5 years, were analysed with the focus on declaratives. Syntactic development was gauged in terms of changes in the mean length of utterance, sentence type and structure, syntactic complexity, and verb pattern, and age-related develpments in these were found. Significant sex differences were found in syntactic development, with girls outperforming boys in mean utterance length, some sentence types and structures, and syntactic complexity, with a significant age by sex interaction in the group of 4-year-olds. The period between age 3 and age 4 was identified as critical for syntactic development, as many linguistic changes occurred in this time. Growth in the ability to use compound sentences was found to be the most significant contributor to increased mean length of utterance. Biological, psychological, and sociocontextual factors influencing these sex differences in language performance are explored and discussed. The generality of the educational implications is discussed.
The CD8α+ Dendritic Cell Is Responsible for Inducing Peripheral Self-Tolerance to Tissue-associated Antigens
Authors: Belz Gabrielle T. , Behrens Georg M.N. , Smith Chris M. , Miller Jacques F.A.P. , Jones Claerwen , Lejon Kristina , Fathman C. Garrison , Mueller Scott N. , Shortman Ken , Carbone Francis R. , Heath William R.
Published: October 2002

We previously described a mechanism for the maintenance of peripheral self-tolerance. This involves the cross-presentation of tissue-associated antigens by a bone marrow–derived cell type that stimulates the proliferation and ultimate deletion of self-reactive CD8 T cells. This process has been referred to as cross-tolerance. Here, we characterize the elusive cell type responsible for inducing cross-tolerance as a CD8α+ dendritic cell (DC). To achieve this aim, transgenic mice were generated expressing yellow fluorescent protein (YFP) linked to CTL epitopes for ovalbumin and glycoprotein B (gB) of herpes simplex virus under the rat insulin promoter (RIP). Although tracking of YFP was inconclusive, the use of a highly sensitive gB-specific hybridoma that produced β-galactosidase on encounter with antigen, enabled detection of antigen presentation by cells isolated from the pancreatic lymph node. This showed that a CD11c+CD8α+ cell was responsible for cross-tolerance, the same DC subset as previously implicated in cross-priming. These data indicate that CD8α+ DCs play a critical role in both tolerance and immunity to cell-associated antigens, providing a potential mechanism by which cytotoxic T lymphocyte can be immunized to viral antigens while maintaining tolerance to self.
Yersinia V–Antigen Exploits Toll-like Receptor 2 and CD14 for Interleukin 10–mediated Immunosuppression
Authors: Sing Andreas , Rost Dagmar , Tvardovskaia Natalia , Roggenkamp Andreas , Wiedemann Agnès , Kirschning Carsten J. , Aepfelbacher Martin , Heesemann Jürgen
Published: October 2002

A characteristic of the three human-pathogenic Yersinia spp. (the plague agent Yersinia pestis and the enteropathogenic Yersinia pseudotuberculosis and Yersinia enterocolitica) is the expression of the virulence (V)-antigen (LcrV). LcrV is a released protein which is involved in contact-induced secretion of yersinia antihost proteins and in evasion of the host's innate immune response. Here we report that recombinant LcrV signals in a CD14- and toll-like receptor 2 (TLR2)-dependent fashion leading to immunosuppression by interleukin 10 induction. The impact of this immunosuppressive effect for yersinia pathogenesis is underlined by the observation that TLR2-deficient mice are less susceptible to oral Y. enterocolitica infection than isogenic wild-type animals. In summary, these data demonstrate a new ligand specificity of TLR2, as LcrV is the first known secreted and nonlipidated virulence-associated protein of a Gram-negative bacterium using TLR2 for cell activation. We conclude that yersiniae might exploit host innate pattern recognition molecules and defense mechanisms to evade the host immune response.
Immune Tolerance After Delivery of Dying Cells to Dendritic Cells In Situ
Authors: Liu Kang , Iyoda Tomonori , Saternus Marzena , Kimura Yukino , Inaba Kayo , Steinman Ralph M.
Published: October 2002

Peripheral immune tolerance is believed to be induced by the processing and presentation of self-tissues that die during physiologic tissue turnover. To examine the mechanism that mediates tolerance, we injected mice with dying syngeneic TAP−/− splenocytes loaded with small amounts of the protein antigen, ovalbumin (OVA). After ingestion and presentation of cell-associated OVA by the CD8+ subset of dendritic cells in situ, large numbers of antigen-reactive, CD8+ T cell receptor (TCR) transgenic T lymphocytes were driven into cell cycle, but then the T cells were deleted. The animals were also tolerant to challenge with OVA in complete Freund's adjuvant. An agonistic anti-CD40 monoclonal antibody was then administered together with the OVA-loaded splenocytes, so that the dendritic cells in the recipient mice would mature. In contrast to observations made in the steady state, the antigen-reactive T cells expanded in numbers for 1–2 wk and produced large amounts of interleukin 2 and interferon γ, while the animals retained responsiveness to antigen rechallenge. The specific tolerance that develops when dendritic cells process self tissues in the steady state should prevent or reduce the development of autoimmunity when dying cells are subsequently processed during infection.
Activation of the innate immunity in Drosophila by endogenous chromosomal DNA that escaped apoptotic degradation
Authors: Mukae Naomi , Yokoyama Hideki , Yokokura Takakazu , Sakoyama Yasuhiko , Nagata Shigekazu
Published: October 2002

Apoptotic cell death is accompanied by degradation of chromosomal DNA. Here, we established in Drosophila a null mutation in the gene for inhibitor of caspase-activated DNase (ICAD) by P-element insertion. We also identified a loss-of-function mutant inDrosophila for DNase II-like acid DNase. The flies deficient in the ICAD gene did not express CAD, and did not undergo apoptotic DNA fragmentation during embryogenesis and oogenesis. In contrast, the deficiency of DNase II enhanced the apoptotic DNA fragmentation in the embryos and ovary, but paradoxically, the mutant flies accumulated a large amount of DNA, particularly in the ovary. This accumulation of DNA in the DNase II mutants caused the constitutive expression of the antibacterial genes for diptericin and attacin, which are usually activated during bacterial infection. The expression of these genes was further enhanced in flies lacking both dICAD and DNase II. These results indicated that CAD and DNase II work independently to degrade chromosomal DNA during apoptosis, and if the DNA is left undigested, it can activate the innate immunity in Drosophila.
Histone chaperone ASF1 cooperates with the Brahma chromatin-remodelling machinery
Authors: Moshkin Yuri M. , Armstrong Jennifer A. , Maeda Robert K. , Tamkun John W. , Verrijzer Peter , Kennison James A. , Karch Francois
Published: October 2002

De novo chromatin assembly into regularly spaced nucleosomal arrays is essential for eukaryotic genome maintenance and inheritance. The Anti-Silencing Function 1 protein (ASF1) has been shown to be a histone chaperone, participating in DNA-replication-coupled nucleosome assembly. We show that mutations in the Drosophila asf1 gene derepress silencing at heterochromatin and that the ASF1 protein has a cell cycle-specific nuclear and cytoplasmic localization. Furthermore, using both genetic and biochemical methods, we demonstrate that ASF1 interacts with the Brahma (SWI/SNF) chromatin-remodelling complex. These findings suggest that ASF1 plays a crucial role in both chromatin assembly and SWI/SNF-mediated chromatin remodelling.
Disruption of mCry2 restores circadian rhythmicity in mPer2 mutant mice
Authors: Oster Henrik , Yasui Akira , van der Horst Gijsbertus T.J. , Albrecht Urs
Published: October 2002

Many biochemical, physiological, and behavioral processes display daily rhythms generated by an internal timekeeping mechanism referred to as the circadian clock. The core oscillator driving this clock is located in the ventral part of the hypothalamus, the so calledsuprachiasmatic nuclei (SCN). At the molecular level, this oscillator is thought to be composed of interlocking autoregulatory feedback loops involving a set of clock genes. Among the components driving the mammalian circadian clock are the Period 1 and 2 (mPer1 and mPer2) and Cryptochrome 1 and 2 (mCry1 and mCry2) genes. A mutation in themPer2 gene leads to a gradual loss of circadian rhythmicity in mice kept in constant darkness (DD). Here we show that inactivation of the mCry2 gene in mPer2 mutant mice restores circadian rhythmicity and normal clock gene expression patterns. Thus,mCry2 can act as a nonallelic suppressor of mPer2, which points to direct or indirect interactions of PER2 and CRY2 proteins. In marked contrast, inactivation of mCry1 inmPer2 mutant mice does not restore circadian rhythmicity but instead results in complete behavioral arrhythmicity in DD, indicating different effects of mCry1 and mCry2 in the clock mechanism
Weaving the museum web: the Virtual Library museums pages
Authors: Bowen Jonathan P.
Published: October 2002

Museums have been discovering the Internet over the past few years like many other information provision sectors. Rather uniquely, they span both educational and commercial sectors, with a concentration of the original objects even in this virtual world. In 1994 the author developed the Virtual Library museums pages (VLmp), an online international distributed museum directory. This is part of the WWW Virtual Library and is also supported by the International Council of Museums (ICOM). The directory is probably still the foremost such resource in this area, but commercial pressures are building, and the resource must develop to ensure its long‐term future. This paper explores the important developments so far, the current situation especially with regard to automatically collected virtual visitor statistics, and possible future directions for the VLmp directory and related resources.
World Library Summit and visits to libraries in Singapore: a report
Authors: Tedd Lucy A.
Published: October 2002

The World Library Summit on Global Knowledge Renaissance was a conference organised by the National Library Board of Singapore in April 2002. An overview of the papers presented which covered the broad themes of knowledge augmentation, cultural entrepreneurship and knowledge governance is given. In addition descriptions of visits made to libraries in Singapore following the conference are provided.
Undergraduate work experience: an alternative approach using micro businesses
Authors: Greenbank Paul
Published: October 2002

Examines the use of micro‐businesses for undergraduate placements on business and management courses. Such businesses are often not considered for placements by HEIs because graduates have tended to obtain employment in larger organisations. However, the graduate labour market is changing and micro‐businesses can be used as a vehicle for linking theory and practice and developing transferable skills. The research involved an in‐depth study of two cases where the author operated as a participant observer. Key factors contributing to the efficacy of the work experience were found to include the preparation of students for their placements; mentoring of both students and placement providers by a suitably qualified academic tutor; and support following the placement to help all the parties involved to reflect and learn from their experience. In particular there is a need for the development of effective learning networks consisting of students, micro‐business owner‐managers and placement tutors.
The disclosure of information on market risk: evidence from the Dow 30
Authors: Blankley Alan , Lamb Reinhold , Schroeder Richard
Published: October 2002

In 1997, the Securities and Exchange Commission (SEC) issued new disclosure rules in an amendment to Regulation S‐X. This release requires the disclosure of both qualitative and quantitative information about market risk by all companies registered with the SEC for annual periods ending after 15 June 1998. Larger companies, with market capitalizations in excess of $2.5 billion, banks, and thrifts were required to apply the regulation’s provisions for annual periods after 15 June 1997. This paper presents results of an analysis of the market risk disclosures by the Dow 30 companies for 1997. The provisions of the amendment requiring the disclosure of qualitative information about market risk by were generally followed by all of the companies contained in the DOW 30. Compliance with the other aspects of the amendment was mixed. These failures might be attributed to confusion over the provisions of the amendment. The results of this study indicate that further evidence is needed on the ability of companies to follow the provisions of the amendment.
Tax audit: Bangladesh panorama
Authors: Sen Dilip Kumar , Bala Swapan Kumar
Published: October 2002

The present paper is a brief study on the modus operandi of the existing income tax audit in Bangladesh. This study centres around: meaning of tax audit; need for tax audit; certain conceptual issues of tax audit; existing scenario of tax audit in Bangladesh, focusing on tax system, tax audit practice, tax audit ambit, tax auditor, tax audit report, existing extent of assessment under tax audit net; and then draws a concluding line with a few recommendations. The paper reflects that the present extent of tax audit practice of Bangladesh is extremely negligible. This paper’s policy prescriptions, if followed, will hopefully provide a great boost in expanding tax audit net, which is much needed for improvement of the internal resource mobilisation in the country.
Market orientation in service
Authors: Esteban Águeda , Millán Ángel , Molina Arturo , Martín‐Consuegra David
Published: October 2002

The association between economic development and growth of the service sector seems indisputable. Although it is necessary to highlight that services are of a different nature from that of products, nowadays the latter are more and more penetrated by complementary services, given the circumstance that services themselves also include, occasionally, the use and consumption of products. Market orientation had been developed mainly in association with tangible products; therefore it is necessary to carry out a study where the evolution of the market orientation is reflected in the service sector independently from industrial sectors. That is why a historical summary of the evolution of market orientation on the service sector has been performed.
The role of environmental education as a tool for environmental management in Cyprus
Authors: Skanavis Constantina , Sarri Evelina
Published: October 2002

This paper examines the social structure and public services in Cyprus. It examines the need for an environmental awareness assessment of the citizens in order to determine how critical thinking and problem solving skills on issues of environmental significance could be promoted. An analysis of environmental health concerns existing in the island is conducted and the educational process taking place, the implemented environmental policy and the extent of citizen participation are studied. The challenge of environmental education in Cyprus is discussed in detail and the environmental awareness efforts are presented. The authors highlight the way in which Cyprus (pursuing membership into the European Union) has to adapt to and implement certain directives, where environmental awareness should be intensely promoted. The authors present the links between each enforced European directive and the relation to the Cypriot way of life. Finally, we discuss why Cyprus will need European aid to implement such policies and how the recommended environmental education program will contribute to a higher quality of life. Recommendations outline details on how to launch a successful non‐formal environmental education program.
Microwave‐enhanced enzyme reaction for protein mapping by mass spectrometry: A new approach to protein digestion in minutes
Authors: Pramanik Birendra N. , Mirza Urooj A. , Ing Yao Hain , Liu Yan‐Hui , Bartner Peter L. , Weber Patricia C. , Bose Ajay K.
Published: October 2002

Accelerated proteolytic cleavage of proteins under controlled microwave irradiation has been achieved. Selective peptide fragmentation by endoproteases trypsin or lysine C led to smaller peptides that were analyzed by matrix‐assisted laser desorption ionization (MALDI) or liquid chromatography‐electrospray ionization (LC‐ESI) techniques. The efficacy of this technique for protein mapping was demonstrated by the mass spectral analyses of the peptide fragmentation of several biologically active proteins, including cytochrome c, ubiquitin, lysozyme, myoglobin, and interferon α‐2b. Most important, using this novel approach digestion of proteins occurs in minutes, in contrast to the hours required by conventional methods.
Structural and nucleotide‐binding properties of YajQ and YnaF, two Escherichia coli proteins of unknown function
Authors: Saveanu Cosmin , Miron Simona , Borza Tudor , Craescu Constantin T. , Labesse Gilles , Gagyi Cristina , Popescu Aurel , Schaeffer Francis , Namane Abdelkader , Laurent‐Winter Christine , Bârzu Octavian , Gilles Anne‐Marie
Published: October 2002

Structural genomics is a new approach in functional assignment of proteins identified via whole‐genome sequencing programs. Its rationale is that nonhomologous proteins performing similar or related biological functions might have similar tertiary structure. We used dye pseudoaffinity chromatography, two‐dimensional gel electrophoresis, and mass spectrometry to identify two novel Escherichia coli nucleotide‐binding proteins, YnaF and YajQ. YnaF exhibited significant sequence identity with MJ0577, an ATP‐binding protein from a hyperthermophile (Methanococcus jannaschii), and with UspA, a protein from Haemophilus influenzae that belongs to the Universal Stress Protein family. YnaF conserves the ATP‐binding site and the dimeric structure observed in the crystal of MJ0577. The protein YajQ, present in many bacterial genomes, is missing in eukaryotes. In the absence of significant similarities of YajQ to any solved structure, we determined its structural and ligand‐binding properties by NMR and isothermal titration calorimetry. We demonstrate that YajQ is composed of two domains, each centered on a β‐sheet, that are connected by two helical segments. NMR studies, corroborated with local sequence conservation among YajQ homologs in various bacteria, indicate that one of the β‐sheets is mostly involved in biological activity.
Molecular dynamics of the FixJ receiver domain: movement of the β4–α4 loop correlates with the in and out flip of Phe101
Authors: Roche Philippe , Mouawad Liliane , Perahia David , Samama Jean‐Pierre , Kahn Daniel
Published: October 2002

FixJ is a two‐domain response regulator involved in nitrogen fixation in Sinorhizobium meliloti. Recent X‐ray characterization of both the native (unphosphorylated) and the active (phosphorylated) states of the protein identify conformational changes of the β4–α4 loop and the conserved residue Phe101 as the key switches in activation. These structures also allowed investigation of the transition between conformations of this two‐component regulatory receiver domain by molecular dynamics simulations. The path for the conformational change was studied with a distance constraint directing the system from one state to the other. The simulations provide evidence for a correlation between the conformation of the β4–α4 loop and the orientation of the residue Phe101. A model presenting the sequence of events during the activation/deactivation process is discussed.
ABSOLUTE CONTINUITY IN PERIODIC WAVEGUIDES
Authors: SOBOLEV ALEXANDER V. , WALTHOE JONATHAN
Published: October 2002

We study second order elliptic operators with periodic coefficients in two-dimensional simply connected periodic waveguides with the Dirichlet or Neumann boundary conditions. It is proved that under some mild smoothness restrictions on the coefficients, such operators have purely absolutely continuous spectra. The proof follows a method suggested previously by A. Morame to tackle periodic operators with variable coefficients in dimension 2.

2000 Mathematical Subject Classification: 35J10, 35P05, 35J25.
VINOGRADOV'S INTEGRAL AND BOUNDS FOR THE RIEMANN ZETA FUNCTION
Authors: FORD KEVIN
Published: October 2002

The main result is an upper bound for the Riemann zeta function in the critical strip: $\zeta(\sigma + it) \le A|t|^{B(1 - \sigma)^{3/2}} \log^{2/3} |t|$ with $A = 76.2$ and $B = 4.45$, valid for $\frac12 \le \sigma \le 1$ and $|t| \ge 3$. The previous best constant $B$ was 18.5. Tools include a variant of the Korobov–Vinogradov method of bounding exponential sums, an explicit version of T. D. Wooley's bounds for Vinogradov's integral, and explicit bounds for mean values of exponential sums over numbers without small prime factors, also using methods of Wooley. An auxiliary result is the exponential sum bound $S(N, t) \le 9.463 N^{1 - 1/(133.66\lambda^2)}$, where $N$ is a positive integer, $t$ is a real number, $\lambda = (\log t)/(\log N)$ and

$S(N,t) = \max_{0 < u \le 1} \max_{N < R \le 2N} \left| \sum_{N < n \le R} (n + u)^{-it} \right|.$$

2000 Mathematical Subject Classification: primary 11M06, 11N05, 11L15; secondary 11D72, 11M35.
CORRIGENDA ARITHMETIC OF DIAGONAL QUARTIC SURFACES, II (Proc. London Math. Soc. (3) 80 (2000) 513–544)
Authors: SWINNERTON-DYER SIR PETER
Published: October 2002

2000 Mathematical Subject Classification: 10B10.
Contribution of Kv4 channels toward the A‐type potassium current in murine colonic myocytes
Authors: Amberg Gregory C. , Koh Sang Don , Hatton William J. , Murray Keith J. , Monaghan Kevin , Horowitz Burton , Sanders Kenton M.
Published: October 2002

A rapidly inactivating K+ current (A‐type current; IA) present in murine colonic myocytes is important in maintaining physiological patterns of slow wave electrical activity. The kinetic profile of colonic IA resembles that of Kv4‐derived currents. We examined the contribution of Kv4 α‐subunits to IA in the murine colon using pharmacological, molecular and immunohistochemical approaches. The divalent cation Cd2+ decreased peak IA and shifted the voltage dependence of activation and inactivation to more depolarized potentials. Similar results were observed with La3+. Colonic IA was sensitive to low micromolar concentrations of flecainide (IC50= 11 μM). Quantitative PCR indicated that in colonic and jejunal tissue, Kv4.3 transcripts demonstrate greater relative abundance than transcripts encoding Kv4.1 or Kv4.2. Antibodies revealed greater Kv4.3‐like immunoreactivity than Kv4.2‐like immunoreactivity in colonic myocytes. Kv4‐like immunoreactivity was less evident in jejunal myocytes. To address this finding, we examined the expression of K+ channel‐interacting proteins (KChIPs), which act as positive modulators of Kv4‐mediated currents. Qualitative PCR identified transcripts encoding the four known members of the KChIP family in isolated colonic and jejunal myocytes. However, the relative abundance of KChIP transcript was 2.6‐fold greater in colon tissue than in jejunum, as assessed by quantitative PCR, with KChIP1 showing predominance. This observation is in accordance with the amplitude of the A‐type current present in these two tissues, where colonic myocytes possess densities twice that of jejunal myocytes. From this we conclude that Kv4.3, in association with KChIP1, is the major molecular determinant of IA in murine colonic myocytes.
A modelling study of locomotion‐induced hyperpolarization of voltage threshold in cat lumbar motoneurones
Authors: Dai Yue , Jones Kelvin E. , Fedirchuk Brent , McCrea David A. , Jordan Larry M.
Published: October 2002

During fictive locomotion the excitability of adult cat lumbar motoneurones is increased by a reduction (a mean hyperpolarization of ≈6.0 mV) of voltage threshold (Vth) for action potential (AP) initiation that is accompanied by only small changes in AP height and width. Further examination of the experimental data in the present study confirms that Vth lowering is present to a similar degree in both the hyperpolarized and depolarized portions of the locomotor step cycle. This indicates that Vth reduction is a modulation of motoneurone membrane currents throughout the locomotor state rather than being related to the phasic synaptic input within the locomotor cycle. Potential ionic mechanisms of this locomotor‐state‐dependent increase in excitability were examined using three five‐compartment models of the motoneurone innervating slow, fast fatigue resistant and fast fatigable muscle fibres. Passive and active membrane conductances were set to produce input resistance, rheobase, afterhyperpolarization (AHP) and membrane time constant values similar to those measured in adult cat motoneurones in non‐locomoting conditions. The parameters of 10 membrane conductances were then individually altered in an attempt to replicate the hyperpolarization of Vth that occurs in decerebrate cats during fictive locomotion. The goal was to find conductance changes that could produce a greater than 3 mV hyperpolarization of Vth with only small changes in AP height (< 3 mV) and width (< 1.2 ms). Vth reduction without large changes in AP shape could be produced either by increasing fast sodium current or by reducing delayed rectifier potassium current. The most effective Vth reductions were achieved by either increasing the conductance of fast sodium channels or by hyperpolarizing the voltage dependency of their activation. These changes were particularly effective when localized to the initial segment. Reducing the conductance of delayed rectifier channels or depolarizing their activation produced similar but smaller changes in Vth. Changes in current underlying the AHP, the persistent Na+ current, three Ca2+ currents, the ‘h’ mixed cation current, the ‘A’ potassium current and the leak current were either ineffective in reducing Vth or also produced gross changes in the AP. It is suggested that the increased excitability of motoneurones during locomotion could be readily accomplished by hyperpolarizing the voltage dependency of fast sodium channels in the axon hillock by a hitherto unknown neuromodulatory action.
Kir2.4 and Kir2.1 K+ channel subunits co‐assemble: a potential new contributor to inward rectifier current heterogeneity
Authors: Schram Gernot , Melnyk Peter , Pourrier Marc , Wang Zhiguo , Nattel Stanley
Published: October 2002

Heteromeric channel assembly is a potential source of physiological variability. The potential significance of Kir2 subunit heterotetramerization has been controversial, but recent findings suggest that heteromultimerization of Kir2.1‐3 may be significant. This study was designed to investigate whether the recently described Kir2.4 subunit can form heterotetramers with the important subunit Kir2.1, and if so, to investigate whether the resulting heterotetrameric channels are functional. Co‐expression of either dominant negative Kir2.1 or Kir2.4 subunits in Xenopus oocytes with either wild‐type Kir2.1 or 2.4 strongly decreased resulting current amplitude. To examine physical association between Kir2.1 and Kir2.4, Cos‐7 cells were co‐transfected with a His6‐tagged Kir2.1 subunit (Kir2.1‐His6) and a FLAG‐tagged Kir2.4 subunit (Kir2.4‐FLAG). After pulldown with a His6‐binding resin, Kir2.4‐FLAG could be detected in the eluted cell lysate by Western blotting, indicating co‐assembly of Kir2.1‐His6 and Kir2.4‐FLAG. Expression of a tandem construct containing covalently linked Kir2.1 and 2.4 subunits led to robust current expression. Kir2.1‐Kir2.4 tandem subunit expression, as well as co‐injection of Kir2.1 and Kir2.4 cRNA into Xenopus oocytes, produced currents with barium sensitivity greater than that of Kir2.1 or Kir2.4 subunit expression alone. These results show that Kir2.4 subunits can co‐assemble with Kir2.1 subunits, and that co‐assembled channels are functional, with properties different from those of Kir2.4 or Kir2.1 alone. Since Kir2.1 and Kir2.4 mRNAs have been shown to co‐localize in the CNS, Kir2.1 and Kir2.4 heteromultimers might play a role in the heterogeneity of native inward rectifier currents.
Selection of Mutant Cell Lines Resistant to Infection byChlamydia trachomatisandChlamydia pneumoniae
Authors: Fudyk Trevor , Olinger Lynn , Stephens Richard S.
Published: October 2002

The lytic outcome of natural infection byChlamydia trachomatiswas exploited to select CHO (Chinese hamster ovary) cells, following chemical mutagenesis, that were deficient in their ability to sustain productive chlamydial infection. Four distinct mutant cell phenotypes with defects in either attachment or postattachment mechanisms that are required for infection byC. trachomatisandChlamydia pneumoniaewere characterized.
CHIRAL LAGRANGIANS
Authors: BIJNENS JOHAN
Published: October 2002

An overview of the field of Chiral Lagrangians is given. This includes Chiral Perturbation Theory and resummations to extend it to higher energies, applications to the muon anomalous magnetic moment, ∊′/∊ and others.
PROTON AND PHOTON STRUCTURE
Authors: ERDMANN MARTIN
Published: October 2002

The increasing precision of the measurements on the proton structure and an improved treatment of the correlated systematic experimental errors constitute a major step forward in our understanding of the flavour decomposition of the proton and the momentum distributions of the various flavours. Together with theoretical progress on the next-to-next-to-leading order QCD corrections to deep inelastic scattering processes, the proton measurements already imply a new level of precision for the strong coupling constant αs. The progress in the measurements on the quantum fluctuations of the photon allows questions on the universal properties of hadronic structures to be addressed.
DIFFRACTIVE PHENOMENA
Authors: IACOBUCCI GIUSEPPE
Published: October 2002

The most recent theoretical and experimental results in the field of diffractive scattering are reviewed. A parallel between the two current theoretical approaches to diffraction, the DIS picture in the Breit frame and the dipole picture in the target frame, is given, accompanied by a description of the models to which the data are compared. A recent calculation of the rescattering corrections, which hints at the universality of the diffractive parton distribution functions, is presented. The concept of generalized parton distributions is discussed together with the first measurement of the processes which might give access to them. Particular emphasis is given to the HERA data, to motivate why hard diffraction in deep inelastic scattering is viewed as an unrivalled instrument to shed light on the still obscure aspects of hadronic interactions.
THE MUON ANOMALY: EXPERIMENT AND THEORY
Authors:   For the Muon (g-2) Collaboration., MILLER J. P.
Published: October 2002

A summary is given of the present status of the theory and experiment of the anomalous magnetic moment of the muon. A difference between predicted and measured values is an indication of physics beyond the Standard Model. A new experimental measurements has produced a value which differs from a recent Standard Model prediction by about 1.6 standard deviations. When first announced, the discrepancy was about 2.6 standard deviations, but theorists have recently found an error in the sign of the largest term in standard model hadronic light-by-light contribution which reduces the difference. Additional data are being analyzed and elements of the theory are being scrutinized to provide, in the future, a sharper test of theory.
SEARCHES FOR NEW PARTICLES
Authors: HANSON GAIL G.
Published: October 2002

The status of searches for new particles and new physics during the past year at the Fermilab Tevatron, at HERA and at LEP is summarized. A discussion of the hints for the Standard Model Higgs boson from LEP2 data is presented. Searches for non-Standard Model Higgs bosons are also described. Many searches have been carried out for the particles predicted by supersymmetry theories, and a sampling of these is given. There have also been searches for flavor changing neutral currents in the interactions of the top quark. In addition, searches for excited leptons, leptoquarks and technicolor are summarized.
ASTROD–AN OVERVIEW
Authors: NI WEI-TOU
Published: October 2002

The objectives of the Astrodynamical Space Test of Relativity using Optical Devices (ASTROD) Mission concept are threefold. The first objective is to discover and explore fundamental physical laws governing matter, space and time via testing relativistic gravity with 3-6 orders of magnitude improvement. Relativistic gravity is an important cornerstone of physics, astronomy and cosmology. Its improved test is crucial to cosmology and modern theories of gravitation including superstring theories. Included in this objective is the precise determination of the relativistic parameters β and γ, the improved measurement of Ġ and a precise determination of an anomalous, constant acceleration directed towards the Sun. The second objective of the ASTROD mission is the high-precision measurement of the solar-system parameter. This includes: (i) a measurements of solar angular momentum via Lense-Thirring effect and the detection of solar g-mode oscillations via their changing gravity field, thus, providing a new eye to see inside the Sun; (ii) precise determination of the planetary orbit elements and masses; (iii) better determination of the orbits and masses of major asteroids. These measurements give better solar dynamics and probe the origin of our solar system. The third objective is to detect and observe gravitational waves from massive black holes and galactic binary stars in the frequency range 50 μHz to 5 mHz. Background gravitational -waves will also be explored. A desirable implementation is to have two spacecraft in separate solar orbit carrying a payload of a proof mass, two telescopes, two 1-2 W lasers, a clock and a drag-free system, together with an Earth reference system. the two spacecraft range coherently with the Earth reference system using lasers. When they are near, they range coherently to each other. The Earth reference system could be ground stations, Earth satellites and/or spacecraft near Earth-Sun Lagrange points. In this overview, we discuss the payload concept, the technological requirements, technological developments, orbit design, orbit simulation, the measurement of solar angular momentum, the gravitational-wave detection sensitivity, and the solar g-mode detection possibility for this mission concept. A simplified mission, Mini-ASTROD with one spacecraft ranging optically with ground stations, together with Super-ASTROD with four spacecraft of 5 AU (Jupiter-like) orbits, will be mentioned in the end. Super-ASTROD is a dedicated low-frequency gravitational-wave detection concept. For Mini-ASTROD, the first objective of ASTROD will be largely achieved; the second objective will be partially achieved; for gravitational wave detection, the sensitivity will be better than the present-day sensitivity using Doppler tracking by radio waves.
THE IAU RESOLUTION ON TIME SCALES AND REFERENCE SYSTEMS AND ITS IMPACT ON ASTROD
Authors: HUANG TIAN-YI , TAO JIN-HE
Published: October 2002

Since 1976 the International Astronomical Union (IAU) has made a series of resolutions on the reference systems and time scales for high precision data processing in the frame- work of general relativity. This article reviews those resolutions that closely relate with the ASTROD project. We give our comments on how to meet the IAU resolutions in the future ASTROD data processing and what kind of works that need to be done further. For example, the self-gravitation terms should be included in the motion equation of the Earth, which is not included in the present DE ephemerides. And the effect of the Sun's figure on the motion of photons should be considered, which is partly neglected in the IAU metric. We also give the metric and the motion equations for both planets and photons in the parameterized post-Newtonian (PPN) formalism. A further improvement of the framework to the second post-Newtonian (2PN) precision would be necessary for the ASTROD project.
ELECTROMAGNETIC DETECTION OF HIGH-FREQUENCY GRAVITATIONAL WAVES
Authors: LI FANG-YU , TANG MENG-XI
Published: October 2002

Unlike usual astrophysical sources of gravitational wave (GW), strong electromagnetic (EM) oscillation systems, high-energy particle beams, solar plasma and crystal arrays are able to produce GWs of extremely high-frequency. Their frequencies may reach up to 108 Hz or higher, but the corresponding amplitude orders are only 10-33 - 10-40. We review the possibility of EM detection for the above GWs. In addition, the maximal signal of high-frequency relic GWs, recently expected by quintessential inflationary models, may be firmly localized in the GHz region. We estimate perturbative effects of the relic GWs to the EM detection systems, and show that the effects can possibly provide a new scheme for the EM detection of the relic GW in the GHz window.
POSSIBLE LINK BETWEEN THE CHANGING FINE-STRUCTURE CONSTANT AND THE ACCELERATING UNIVERSE VIA SCALAR-TENSOR THEORY
Authors: FUJII YASUNORI
Published: October 2002

In 1976, Shlyakhter showed that the Sm data from Oklo results in the upper bound on the time-variability of the fine-structure constant: [Formula: see text], which has ever been the most stringent bound. Since the details have never been published, however, we recently re-analyzed the latest data according to Shlyakhter's recipe. We nearly re-confirmed his results. To be more precise, however, the Sm data gives either an upper-bound or an evidence for a changing [Formula: see text]. A remark is made to a similar re-analysis due to Damour and Dyson. We also compare our result with a recent "evidence" due to Webb et al, obtained from distant QSO's. We point out a possible connection between this time-dependence and the behavior of a scalar field supposed to be responsible for the acceleration of the universe, also revealed recently.
A PARADOX OF INTUITION: HEDGING THE LIMIT OR HEDGING IN THE LIMIT?
Authors: SOBEHART J. R. , KEENAN S. C.
Published: October 2002

Here we review the notion of covergence in Itô calculus and its application to the Black-Scholes options pricing model and its extensions. The concept of covergence is fundamental to the development of the differential calculus of stochastic processes. It is also the key to understanding the validity of the no arbitrage condition imposed by Black and Scholes (1973) that leads to their options pricing equation.
SET-VALUED PSEUDOMONOTONE MAPS AND DEGENERATE EVOLUTION INCLUSIONS
Authors: KUTTLER KENNETH L. , SHILLOR MEIR
Published: October 2002

We develop the theory of evolution inclusions for set-valued pseudomonotone maps. The problems we investigate are [Formula: see text] where B=B(t) is a linear operator that may vanish and A is a set-valued pseudomonotone operator. We prove the existence of unique solutions of such, possibly degenerate, problems.

We apply the theory to the problem of dynamic frictional contact with a slip dependent friction coefficient and prove the existence of its unique weak solution.

This theory opens the way for the investigation of sophisticated dynamical models in mechanics and frictional contact problems.
How to Fix the Edge Effect of Catheter-Based Radiation Therapy in Stented Arteries
Authors: Cheneau Edouard , Waksman Ron , Yazdi Hamid , Chan Rosanna , Fourdnadjiev Jana , Berzingi Chalak , Shah Vivek , Ajani Andrew E. , Leborgne Laurent , Tio Fermin O.
Published: October 2002

Background—

Edge stenosis remains a serious limitation of catheter-based vascular brachytherapy (VBT). This study aims to identify the mechanisms and evaluate strategies to minimize edge restenosis in patients treated with VBT.

Methods and Results—

Thirty-four porcine stented coronary arteries were irradiated (doses of 15 or 22 Gy) with
192
Ir trains of either 6 seeds (23 mm) with 0 mm coverage at the distal stent edge and 10 mm at the proximal stent edge or 14 seeds (55 mm) centered at the distal edge of the stent with 27.5 and 14.5 mm coverage at the distal and proximal edges, respectively. After VBT, an additional 13-mm stent was positioned overlapping the distal margin of the first stent. Animals were killed at 28 days, and arteries were analyzed. Longer radiation margins were associated with reduced intimal area (IA) at the stent edge: 2.3±0.9, 3.6±2.0, and 5.3±2.2 mm
2
with 15 Gy for a radiation margin of 14.5, 10, and −13 mm (−13 versus 10,
P
=0.06; 10 versus 14.5,
P
=0.06). Additional stenting was associated with an increase of IA: 4.0±2.3 mm
2
at the overlapped segment. Increasing the dose to 22 Gy resulted in a reduction of the IA at the overlap segment to 1.31±0.57 mm
2
with 14 seeds (27.5 mm coverage) but was not helpful with 6 seeds (0 mm coverage): IA, 5.56±2.28 mm
2
.

Conclusions—

Extending the radiation margins to 14.5 mm from each end of the stent minimized the edge-effect phenomenon. A higher dose is essential to eliminate further increases in IA at the overlapped segment with additional stents.
Targeted Deletion of Angiotensin II Type 2 Receptor Caused Cardiac Rupture After Acute Myocardial Infarction
Authors: Ichihara Sahoko , Senbonmatsu Takaaki , Price Edward , Ichiki Toshihiro , Gaffney F. Andrew , Inagami Tadashi
Published: October 2002

Background—

Accumulating evidence has suggested that the cardiac renin-angiotensin system is activated during the remodeling process after myocardial infarction (MI). Although 2 types of angiotensin II receptors (AT
1
and AT
2
) are upregulated in the infarcted tissue, the contribution of AT
2
to the subsequent fibrogenetic phase of wound healing is less certain. This study was conducted to evaluate the role of AT
2
in wound healing after MI using an in vivo intervention study in mice with MI.

Methods and Results—

We examined myocardial hypertrophy, cardiac fibrosis, and morphological evidence of fibrillar collagen accumulation at the infarcted and noninfarcted regions in male mice lacking the AT
2
receptor (
Agtr
2−/Y) and age-matched wild-type (WT) animals. Of the
Agtr
2−/Y mice, 63.6% died of cardiac rupture, whereas 23.5% of the WT mice died of the same cause within 1 week. The extent of fibrosis and that of collagen gene expression in
Agtr
2−/Y mice were significantly reduced compared with WT mice at 1 week after coronary ligation. Furthermore, MI resulted in a marked increase in the prostaglandin E
2
(PGE
2
) level at 4 days after surgery in
Agtr
2−/Y mice. In WT mice, the PGE
2
level was also elevated after MI but to a significantly lesser extent than in
Agtr
2−/Y mice.

Conclusions—

A chronic loss of AT
2
by gene targeting prevented the collagen deposition and caused cardiac rupture. The markedly elevated PGE
2
may be a mechanism that inhibits collagen synthesis in the infarcted region of
Agtr
2−/Y mice.
Stimulation of Id1 Expression by Bone Morphogenetic Protein Is Sufficient and Necessary for Bone Morphogenetic Protein–Induced Activation of Endothelial Cells
Authors: Valdimarsdottir Gudrun , Goumans Marie-José , Rosendahl Alexander , Brugman Martijn , Itoh Susumu , Lebrin Franck , Sideras Paschalis , ten Dijke Peter
Published: October 2002

Background—

Bone morphogenetic proteins (BMPs) are multifunctional proteins that regulate the proliferation, differentiation, and migration of a large variety of cell types. Like other members of the transforming growth factor-β family, BMPs elicit their cellular effects through activating specific combinations of type I and type II serine/threonine kinase receptors and their downstream effector proteins, which are termed Smads. In the present study, we investigated BMP receptor/Smad expression and signaling in endothelial cells (ECs) and examined the effects of BMP on EC behavior.

Methods and Results—

Immunohistochemical analysis of tissue sections of human colon and mouse heart and aorta showed that BMP receptors are expressed in ECs in vivo. Bovine aortic ECs and mouse embryonic ECs were found to express BMP receptors and their Smads. BMP receptor activation induced the phosphorylation of specific Smad proteins and promoted EC migration and tube formation. Id1 was identified as a BMP/Smad target in ECs. Ectopic expression of Id1 mimicked BMP-induced effects. Importantly, specific interference with Id1 expression blocked BMP-induced EC migration.

Conclusions—

The BMP/Smad pathway can potently activate the endothelium. Id1 expression is strongly induced by BMP in ECs. Ectopic expression of Id1 induces EC migration and tube formation. Moreover, Id1 played a critical role in mediating BMP-induced EC migration.