bluuebunny/crossref_metadata_2025 huggingface dataset:
Heavily melanotic perivascular epithelioid clear cell tumor of the kidney
Authors: Adachi Shiro , Hanada Masato , Kobayashi Yoshiyuki , Tsutahara Kohichi , Fukuhara Shin‐ichiro , Mori Naoki , Hara Tsuneo , Mukai Hideyo , Shimasaku Emi , Kawai Masaru , Kishikawa Naoto , Yamaguchi Seiji
Published: March 2004

A black‐colored and well‐circumscribed renal tumor in a 71‐year‐old woman is reported. The tumor was unique in that  it was rich in vasculature and exclusively composed of perivascular epithelioid clear cells. Morphological features were reminiscent of conventional renal cell carcinoma (RCC). However, immunohistochemical examinations showed that the tumor cells did not express any epithelial markers, but diffusely and intensely expressed a melanocytic marker, gp‐100/HMB‐45. Another striking feature of the tumor was a large amount of cytoplasmic pigment that made the tumor wholly black. The pigment was not stained with Berlin‐blue, completely bleached with potassium permanganate, and stained with Fontana‐Masson staining, which suggests that the pigment was melanin. Morphological features and immunohistochemical findings indicated that the present tumor was an extreme example of a perivascular epithelioid clear cell tumor with a large amount of melanin, which has not been previously reported. One should be aware of the pure form of perivascular  epithelioid clear cell tumor of the kidney because it is sometimes very difficult to differentiate this tumor from conventional RCC. Immunohistochemical examinations and the presence of cytoplasmic melanin can help the differentiation.
Cushing's syndrome due to a large adrenocortical adenoma with histological features simulating ACTH‐independent macronodular adrenocortical hyperplasia
Authors: Karasawa Rie , Hotta Mari , Aiba Motohiko , Takano Kazue
Published: March 2004

A 53‐year‐old woman presented with Cushing's syndrome resulting from an adrenocortical adenoma, 6.5 cm in diameter and 75 g in weight, which is larger than usual. Endocrinological data of this patient showed adrenocorticotropin (ACTH)‐independent hypercortisolemia. A computed tomography scan of the adrenal glands revealed a single large and well‐encapsulated tumor with an irregularly shaped area of calcification and loss of parenchyma on the left adrenal. The right adrenal gland was atrophic. Laparoscopic removal of the left adrenal tumor was performed. The tumor was lobulated and clearly encapsulated, and the non‐neoplastic area of the left adrenal was atrophic without any nodularity. The histological analysis confirmed the diagnosis of adrenal adenoma. In addition, this adenoma displayed histopathological features in common with ACTH‐independent macronodular adrenocortical hyperplasia (AIMAH), including clear cell predominance, a pattern of small compact cell nests in clear cell areas, and very long cord‐like arrangement of small compact cells. In AIMAH, adrenals are extremely enlarged and are more massive than in any other subtype of Cushing's syndrome. The fact that the present adrenocortical adenoma was larger than those typical adenomas of Cushing's syndrome may reflect an AIMAH‐type cellular composition of clear cell predominance and small compact cell nests.
Detection of glyceraldehyde 3‐phosphate dehydrogenase messenger RNA using a peptide nucleic acid probe in paraffin‐embedded archival specimens
Authors: Hiroyasu Makoto , Akatsuka Shinya , Shirase Tomoyuki , Toda Yoshinobu , Hiai Hiroshi , Toyokuni Shinya
Published: March 2004

Although the human genome project has been completed, the functions of many genes remain undetermined. In situ hybridization (ISH) is a key method for identifying cells in which a given messenger RNA is transcribed. Paraffin‐embedded specimens remain precious materials for research, but preservation of high‐quality RNA in these specimens is not expected unless ample caution was taken during fixation. Peptide nucleic acid (PNA) is a recently developed hybrid molecule with genetic information that has high stability and high affinity to the complementary DNA or RNA. We applied a PNA probe to mRNA ISH of liver specimens obtained by autopsy and embedded in paraffin 28–48 years ago. An 18‐mer PNA probe for glyceraldehyde 3‐phosphate dehydrogenase was used. Staining was then analyzed in association with morphology by hematoxylin and eosin staining, and with the time between death of the patient and tissue fixation. Notably, specimens fixed with formalin and embedded in paraffin 48 years ago yielded excellent results if the time before fixation was short enough (<8 h). There was a significant inverse correlation between the intensity of ISH staining and the time before fixation. Oligonucleotide PNA probe, albeit at high cost, would increase the value of paraffin‐embedded specimens in storage for use in human medical research.
Ovarian teratoma showing a predominant hemangiomatous element with stromal luteinization: Report of a case and review of the literature
Authors: Itoh Hiroshi , Wada Toshiro , Michikata Kaori , Sato Yuichiro , Seguchi Tomoko , Akiyama Yutaka , Kataoka Hiroaki
Published: March 2004

A solid well‐circumscribed ovarian tumor in a 63‐year‐old Japanese woman is reported. Histologically, the tumor consisted predominantly of a hemangiomatous component with a small cyst lined by a respiratory ciliated epithelium. The remaining ovarian stroma showed a marked proliferation of luteinized cells that were strongly positive for inhibin immunohistochemically. Neither dermoid nor other teratomatous components were found, even in the serial sections of the tumor. To date, vascular tumors of the ovary are uncommon and some cases of ovarian hemangioma have been reported. However, their origin, whether a monodermal teratoma or a true neoplasm arising in the ovarian stroma, has not yet been elucidated. When a hemangiomatous proliferation is found in an ovarian tumor, a thorough microscopic search for teratomatous components is necessary before diagnosing the tumor as a pure hemangioma.
Xanthosis in the Spinal Epidural Space—An Epiduroscopy Finding
Authors: Heavner James E. , Bosscher Hemmo , Dunn Dale , Lehman Travis
Published: March 2004

Abstract: We report the presence of yellow pigment (xanthosis) in the eqidural space of a patient with a chronic painful radiculopathy. A 55‐year‐old Caucasian male patient with a left L5, S1 radiculopathy underwent epiduroscopy and epidural neurolysis. Epiduroscopy findings in the area of the nerve root associated with the radiculopathy included the presence of diffuse perivascular yellow pigments, increased vascularity and diffuse increased presence of sheets of fibrous tissue. This is a novo epiduroscopy finding. The case demonstrates the potential for epiduroscopy to expand our knowledge about pathological changes associated with some chronic painful conditions.
NO Pain: Potential Roles of Nitric Oxide in Neuropathic Pain
Authors: Levy Dan , Zochodne Douglas W.
Published: March 2004

Abstract:  The disabling human syndrome of “neuropathic pain” is an intractable complication of peripheral nerve injury or degeneration. A complex interaction between injured peripheral axons, sensory neurons and central nervous system signaling is thought to account for it. In this brief review, we present evidence that the free radical signaling molecule, nitric oxide (NO) may act at several levels of the nervous system during the development of experimental neuropathic pain. For example, NO may directly influence injured axons in the periphery, may indirectly influence pain by its role in the process of Wallerian degeneration, and may signal in the dorsal horn of the spinal cord. While it is premature to argue for therapeutic approaches that alter NO actions, it may be an important player in the cascade of events that generate neuropathic pain.
Strategic Collaborative Model for Evidence‐Based Nursing Practice
Authors: Olade Rosaline A.
Published: March 2004

Purpose: To describe a model that has been developed to guide nurses and other health professionals in collaborative efforts toward evidence‐based nursing practice.

Method: A review of literature was conducted using MEDLINE and CINAHL to search for articles on research utilization for evidence‐based practice in health care delivery. Empirical studies; reviews; and theoretical, opinion, and information articles were included in the review in order to provide a more comprehensive view of the state of evidence‐based nursing internationally.

Findings: Findings revealed a number of barriers to evidence‐based nursing practice, which have persisted over the last two decades, including inadequate knowledge of research among practicing nurses, lack of administrative support for research activities in clinical settings, lack of empowerment of nurses, and lack of needed mentoring from nursing research consultants.

Conclusions: Barriers in the areas of nursing education and administrative support appear to be major. A need was identified for a pragmatic model that encourages cooperation and collaboration between educators/researchers in academia and the administrative leaders in the clinical facilities if evidence‐based nursing practice is to become the norm.

Framework of Model: The Tyler Collaborative Model is based on an eclectic approach to planned change for creating evidence‐based practice. This model identifies a step‐by‐step process for change, while allowing for the opportunity to integrate any of the previously available methods of critical appraisal to determine the best evidence for practice in each clinical setting.
Fortuitous Phenomena: On Complexity, Pragmatic Randomised Controlled Trials, and Knowledge for Evidence‐Based Practice
Authors: Thompson Carl
Published: March 2004

Context: Many of the interventions that nurses develop and implement are in themselves complex and have to operate in situations of irreducible complexity and uncertainty.

Main Argument: This article argues that the primary means of generating knowledge for the evidence‐based deployment of complex interventions should be the pragmatic randomised controlled trial. Randomised controlled trials represent the only research design to adequately deal with that which we know and (far more importantly) that which we do not.

Literary Method: Using the example of practice development as an exemplar for complexity, and drawing on the objections often voiced as a response to calls to make use of randomised controlled trials in nursing and nursing research, the article presents a developmental framework and some methodological solutions to problems often encountered.

Conclusion: Randomised controlled trials, whilst undoubtedly methodologically and strategically challenging, offer the most robust basis for developing primary research knowledge on the effects of complex interventions in nursing and their active components.
Conducting Translation Research in the Home Care Setting: Lessons from a Just‐in‐Time Reminder Study
Authors: Feldman Penny Hollander , McDonald Margaret V.
Published: March 2004

Background: Home care organizations are relatively isolated from academic health centers, university‐based schools of nursing, and centers of health services research that have advanced the knowledge base for quality improvement. Thus limited information exists about how best to promote evidence‐based practice in this setting.

Aims: This article examines research and translation issues posed by the decentralized home care setting and considers how these issues compare to issues in other settings.

Methods: A case study approach is used to frame a discussion of the contextual and practical factors that can influence the design and future acceptance of different translation strategies in the home care setting. Use of a recently concluded randomized trial that tested the effectiveness of two interventions designed to improve the adoption of evidence‐based practices by home health nurses has been made to inform this discussion.

Discussion: Effective translation interventions in home health care need to address the unique nature of this setting including the dispersed, generalist workforce that serves a diverse patient population and lacks strong peer contact or on‐site support and supervision. Proactive push translation strategies such as reminders that have been effective in other settings show promise in this service area but had a differential effect across conditions. Significantly, the cost‐effectiveness analysis of this intervention showed that net patient care costs actually increased for one condition.

Implications: The study described in this article demonstrates that rigorous translation research can be conducted in highly decentralized practice settings. It also points to the value of assessing different levels of intensity of interventions in a single study, looking at process measures and patient outcomes, and conducting a cost‐effectiveness analysis. To encourage broader adoption of translation strategies, additional incentives from purchasing or regulatory agencies may be needed.
Methods in Translation Science
Authors: Titler Marita G.
Published: March 2004

Background: The gap between research findings and practice has been, and continues to be, a concern for the international community. A number of descriptive studies have elucidated barriers and facilitators of evidence‐based practice in nursing. It is argued that it is now time to use findings from these studies to design and test interventions that explicitly target barriers to the use of evidence in practice rather than doing further research to describe generic barriers and facilitators to evidence‐based practice. This article discusses research methods to advance our knowledge regarding the efficacy of translating research into practice (TRIP) interventions that promote and hasten adoption of evidence in practice.

Approach: Published research is reviewed and used as exemplars of translation studies. The benefits and challenges in studying natural experiments are addressed as are the benefits and challenges in conducting TRIP studies using experimental designs.

Discussion: The article discusses factors such as sample attainment, unit of analysis, intervention characteristics, outcome measurement, and sustainability. Although there are a myriad of initiatives aimed at increasing use of evidence in practice, there is little systematic evidence of the effectiveness of these initiatives. In order to advance knowledge, translation research needs more experimental studies that test TRIP interventions through, for example, partnership models.
Evidence Review on Older People's Views and Experiences of Falls Prevention Strategies
Authors: McInnes Elizabeth , Askie Lisa
Published: March 2004

Background: A systematic review was undertaken of qualitative and quantitative studies and reviews that focus on older people's views and experiences of falls prevention. The review was undertaken to provide an additional dimension to the clinical effectiveness evidence provided by a Cochrane review on falls prevention (Gillespie et al. 2003) to inform the development of a national guideline on falls prevention in older people. As guideline recommendations or policies relating to preventive strategies have the potential to increase health care costs, it is important that all sources of evidence are reviewed by guideline development groups so that an understanding is achieved of the acceptability and sustainability of interventions in relation to different groups and settings.

Method: Accordingly, this review examined the literature on the views, preferences, and experiences of older people in relation to falls prevention strategies. Twenty‐four studies meeting the inclusion criteria were critically reviewed and were then summarized into evidence tables. The key facilitators and barriers to participation in falls prevention programs were derived from the commonly occurring and consistent themes arising from the reviewed studies. The implications of these findings for the clinical effectiveness review conclusions were then taken into account.

Findings: Several important findings emerged. These included preferences for falls prevention strategies not involving behaviour change among some groups, the need to promote the social value of falls prevention programs, and the importance of identifying and addressing factors associated with activity avoidance.

Conclusions and Implications: In terms of the impact of these findings on the Cochrane review, the most important implication is that although trials of multifactorial falls prevention packages have reported beneficial results, in clinical practice it is important to consult with individual potential participants and find out what characteristics they are willing to modify, and what changes they are prepared to make to reduce their risk of falling. Otherwise, there is the risk that expensive programs are not properly targeted or fail to achieve maximum participation rates. Further work on the most robust and pragmatic methods of synthesizing disparate studies on patients' views and preferences to inform evidence‐based guideline recommendations is needed.
MAXIMAL COACTIONS
Authors: ECHTERHOFF SIEGFRIED , KALISZEWSKI S. , QUIGG JOHN
Published: March 2004

A coaction δ of a locally compact group G on a C*-algebra A is maximal if a certain natural map from [Formula: see text] onto [Formula: see text] is an isomorphism. All dual coactions on full crossed products by group actions are maximal; a discrete coaction is maximal if and only if A is the full cross-sectional algebra of the corresponding Fell bundle. For every nondegenerate coaction of G on A, there is a maximal coaction of G on an extension of A such that the quotient map induces an isomorphism of the crossed products.
COVERING DIMENSION AND QUASIDIAGONALITY
Authors: KIRCHBERG EBERHARD , WINTER WILHELM
Published: March 2004

We introduce the decomposition rank, a notion of covering dimension for nuclear C*-algebras. The decomposition rank generalizes ordinary covering dimension and has nice permanence properties; in particular, it behaves well with respect to direct sums, quotients, inductive limits, unitization and quasidiagonal extensions. Moreover, it passes to hereditary subalgebras and is invariant under stabilization. It turns out that the decomposition rank can be finite only for strongly quasidiagonal C*-algebras and that it is closely related to the classification program.
COMPACTNESS OF CERTAIN FAMILIES OF PSEUDO-HOLOMORPHIC MAPPINGS INTO ${\mathbb C}^n$
Authors: GAUSSIER HERVÉ , KIM KANG-TAE
Published: March 2004

We present a normal family theorem for injective almost holomorphic maps from a manifold with almost complex structures into [Formula: see text]. Our theorem implies a new consequence even for the holomorphic mappings of a complex manifold into [Formula: see text], which can be seen as a generalization of the convergence theorem for Frankel's scaling sequence whose images are not necessarily convex. Moreover, our method is closer in spirit to the circle of ideas centered around the classical Montel theorem.
MODULARITY ON VERTEX OPERATOR ALGEBRAS ARISING FROM SEMISIMPLE PRIMARY VECTORS
Authors: YAMAUCHI HIROSHI
Published: March 2004

In this article, using an idea of the physics superselection principal, we study a modularity on vertex operator algebras arising from semisimple primary vectors. We generalizes the theta functions on vertex operator algebras and prove that the internal automorphisms do not change the genus one twisted conformal blocks.
GAP CONDITION AND SELF-DUALIZED ${\mathcal N}=4$ SUPER-YANG–MILLS THEORY FOR ADE GAUGE GROUP ON K3
Authors: SASAKI TORU
Published: March 2004

We try to determine the partition function of [Formula: see text] super-Yang–Mills theory for ADE gauge group on K3 by self-dualizing our previous ADE partition function. The resulting partition function satisfies gap condition.
THE DIFFICULTY IN THE DECAY CONSTANTS AND SPECTRA OF $D^*_{sJ}$
Authors: HSIEH RON-CHOU , CHEN CHUAN-HUNG , GENG CHAO-QIANG
Published: March 2004

We examine the compatibility in predicted masses and the decay constants of [Formula: see text] mesons in terms of two-quark contents. We find that the results of a specific model, which is governed by heavy quark limit, will encounter a challenge to fit both spectra and decay constants simultaneously.
COMPLETE BREMSSTRAHLUNG CORRECTIONS TO THE FORWARD–BACKWARD ASYMMETRIES IN b→Xsℓ+ℓ-
Authors: ASATRIAN H. M. , ASATRYAN H. H. , HOVHANNISYAN A. , POGHOSYAN V.
Published: March 2004

In a recent paper we presented a calculation of NNLL virtual corrections to the forward–backward asymmetries in b→Xsℓ+ℓ- decay. That result does not include bremsstrahlung corrections which are free from infrared and collinear singularities. In the present paper we include the remaining [Formula: see text] bremsstrahlung corrections to the forward–backward asymmetries in b→Xsℓ+ℓ- decay. The numerical effect of the calculated contributions is found to be below 1%.
HALO STRUCTURE OF 11Li IN A THREE-BODY MODEL
Authors: KUMAR S. , BHASIN V. S.
Published: March 2004

A three-body model proposed earlier (S. Kumar and V. S. Bhasin, Phys. Rev.C65, 034007 (2002)) to set up the wave function of 11 Li is extended to investigate structural properties of 11 Li like matter radius, momentum distributions of the halo neutrons and the core(c), and n–n and n–c correlations. The energies and widths of experimentally observed resonant states of 11 Li in continuum have been calculated by employing the complex scaling method. The model is further extended to study the β-decay of 11 Li to the decay modes: (i) deuteron + 9 Li channel and (ii) 11 Be * (18.3 MeV) state. The results obtained are found to be in reasonably good agreement with the experimental data.
NEED THE MASSES OF UNSTABLE PARTICLES AND THEIR ANTIPARTICLES BE EQUAL IN THE CPT-INVARIANT SYSTEM?
Authors: URBANOWSKI K.
Published: March 2004

We show that the real parts of diagonal matrix elements of the exact effective Hamiltonian governing the time evolution in the subspace of states of neutral kaons and similar particles cannot be equal for t>t0 (t0 is the instant of creation of the pair K0, [Formula: see text]) when the total system under consideration is CPT invariant but CP noninvariant. The unusual consequence of this result is that, contrary to the properties of stable particles, the masses of the unstable particle, e.g. K0, and its antiparticle, [Formula: see text], need not be equal for t≫t0 in the case of preserved CPT and violated CP symmetries.
THE MINIMAL CURVATURE OF THE UNIVERSE IN MODIFIED GRAVITY AND CONFORMAL ANOMALY RESOLUTION OF THE INSTABILITIES
Authors: NOJIRI SHIN'ICHI , ODINTSOV SERGEI D.
Published: March 2004

We discuss the modified gravity which may produce the current cosmic acceleration of the universe and eliminate the need for dark energy. It is shown that such models where the action quickly grows with the decrease of the curvature define the FRW universe with the minimal curvature. Infinite time is required to reach the minimal curvature during the universe evolution. It is demonstrated that quantum effects of conformal fields may strongly suppress the instabilities discovered in modified gravity. We also briefly speculate on the modification of gravity combined with the presence of the cosmological constant dark energy.
LIMITS ON CHARGE NON-CONSERVATION FROM POSSIBLE SEASONAL VARIATIONS OF THE SOLAR NEUTRINO EXPERIMENTS
Authors: TORRES MANUEL , VUCETICH HECTOR
Published: March 2004

Variable speed of light (VSL) theories may lead to large violations of charge conservation that can be written in terms of a dimensionless parameter λ. Similarly, charge non-conservation can arise in theories that break down Einstein's Equivalence Principle, parametrized in terms of Γ0. It is shown that for such theories, the motion of the Earth with respect to the Sun would produce a seasonal variation for the SAGE and GALLEX–GNO experiments. Analyzing the reported counting rates for these experiments, a very stringent bound |λ|≤2×10-19 is obtained, some 109 times smaller than previous ones. For the second example, the corresponding bound is |Γ0|<10-18, which represents an improvement of 107 on the previous result. Furthermore, assuming that the previous conditions apply, the existing bound for the lifetime of the 71 Ga →71 Ge charge-nonconserving decay is improved as: τ CNC ≥1.4×1027 years. Similarly a new upper limit for the ratio of the charge-nonconserving to the normal weak decay of the neutron is obtained: [Formula: see text].
LEPTON FAMILY SYMMETRY AND NEUTRINO MASS MATRIX
Authors: MA ERNEST
Published: March 2004

The standard model of leptons is extended to accommodate a discrete Z3×Z2 family symmetry. After rotating the charged-lepton mass matrix to its diagonal form, the neutrino mass matrix reveals itself as very suitable for explaining atmospheric and solar neutrino oscillation data. A generic requirement of this approach is the appearance of three Higgs doublets at the electroweak scale, with observable flavor violating decays.
NEW BOUNDS ON THE STRING SCALE FROM FLAVOR PHYSICS
Authors: SANTIAGO J.
Published: March 2004

We review the very stringent lower bounds on the string scale that arise from flavor considerations in models with intersecting branes. Despite the absence of a realistic flavor structure at tree level, flavor changing interactions induce a non-trivial pattern of fermion masses and mixing angles when quantum corrections are taken into account. The resulting realistic theory of flavor allows us to constrain, in an unambiguous way, the string scale up to levels difficult to reconcile non-supersymmetric models.
NON-SINGULAR RADIATION COSMOLOGICAL MODELS
Authors: FERNÁNDEZ-JAMBRINA L. , GONZÁLEZ-ROMERO L. M.
Published: March 2004

In this paper we analyse the possibility of constructing singularity-free inhomogeneous cosmological models with a pure radiation field as matter content. It is shown that the conditions for regularity are very easy to implement and therefore there is a huge number of such spacetimes.
AN ENERGY BOUND DEDUCED FROM THE VANISHING OF THE RADIATION REACTION FORCE DURING UNIFORM ACCELERATION
Authors: SORKIN RAFAEL D.
Published: March 2004

We deduce from energy conservation a lower bound on the mass of any system capable of imparting a constant acceleration to a charged body. We also point out a connection between this bound and the so-called dominant energy condition of general relativity.
TWO-BODY CORRELATION CONTRIBUTIONS IN HALO NUCLEI WITH A RELATIVISTIC HARTREE APPROACH
Authors: JIANG W. Z. , ZHU Z. Y. , SHEN W. Q. , QIU X. J. , REN Z. Z.
Published: March 2004

The relativistic density-dependent Hartree framework, where the relativistic two-body correlations are properly incorporated, is developed to study the properties of halo nuclei. The halo nucleon–meson vertex is reconstructed considering the nuclear potentials can be built dominantly from the two-body interactions. The two-neutron halo nucleus 11 Li , together with the one-neutron halo nucleus 19 C , is investigated. Separation energies, root-mean-square (rms) radii, and halo tails of above halo nuclei are nicely reproduced. The correlation contribution which provides essential attractions for halo neutrons is important to guarantee the relation Sn>S2n for 11 Li .
SEMILEPTONIC B-DECAYS AT BABAR
Authors: LANGENEGGER URS
Published: March 2004

We present results on semileptonic B-decays obtained with the BABAR detector. The large data set accumulated at the PEP-II asymmetric-energy B-factory allows a new measurement technique, where the hadronic decay of one B-meson is fully reconstructed and the semileptonic decay of the recoiling B-meson is studied. Traditional analysis techniques of inclusive and exclusive B-decays complement this approach with very high statistics data samples. These measurements play an important role in the tests of the description of CP violation in the Standard Model: The determinations of the Cabibbo-Kobayashi-Maskawa matrix elements |Vcb| and |Vub| provide constraints on the unitarity of the CKM triangle. Furthermore, the experimental measurement of parameters of Heavy Quark Effective Theory test the consistency of the theoretical description of semileptonic B-decays.
THE SCHRÖDINGER WAVE FUNCTIONAL AND CLOSED STRING ROLLING TACHYON
Authors: KLUSOŇ J.
Published: March 2004

In this paper we apply a Schrödinger picture description of the minisuperspace approach to the closed string tachyon condensation. We will calculate the rate of produced closed string and we will show that the density of high massive closed string modes reaches the string density in time of order one in string units.
SUPERFIELD EXTENDED BRST QUANTIZATION IN GENERAL COORDINATES
Authors: GEYER B. , GITMAN D. M. , LAVROV P. M. , MOSHIN P. YU.
Published: March 2004

We propose a superfield formalism of Lagrangian BRST–anti-BRST quantization of arbitrary gauge theories in general coordinates with the base manifold of fields and antifields described in terms of both bosonic and fermionic variables.
DIRAC–KÄHLER FERMION FROM CLIFFORD PRODUCT WITH NONCOMMUTATIVE DIFFERENTIAL FORM ON A LATTICE
Authors: KANAMORI ISSAKU , KAWAMOTO NOBORU
Published: March 2004

We formulate Dirac–Kähler fermion action by introducing a new Clifford product with noncommutative differential form on a lattice. Hermiticity of the Dirac–Kähler action requires to choose the lattice structure having both orientabilities on a link. The Kogut–Susskind fermion and the staggered fermion actions are derived directly from the Dirac–Kähler fermion formulated by the Clifford product. The lattice QCD action with Dirac–Kähler matter fermion is also derived via an inner product defined by the Clifford product.
WAVE PACKETS AND QUANTUM OSCILLATIONS
Authors: DE LEO STEFANO , NISHI CELSO C. , ROTELLI PIETRO P.
Published: March 2004

We give a detailed analysis of the oscillation formula within the context of the wave packet formalism. Particular attention is made to insure flavor eigenstate creation in the physical cases (Δp≠0). This requirement imposes noninstantaneous particle creation in all frames. It is shown that the standard formula is not only exact when the mass wave packets have the same velocity, but it is a good approximation when minimal slippage occurs. For more general situations the oscillation formula contains additional arbitrary parameters, which allows for the unknown form of the wave packet envelope.
MIRROR MATTER ADMIXTURES AND ISOSPIN BREAKING IN THE |ΔI|=1/2 RULE IN Ω- TWO BODY NONLEPTONIC DECAYS
Authors: SÁNCHEZ-COLÓN G. , HUERTA R. , GARCÍA A.
Published: March 2004

We discuss a description of Ω- two body nonleptonic decays based on possible, albeit tiny, admixtures of mirror matter in ordinary hadrons. The |ΔI|=1/2 rule enhancement is obtained as a result of isospin symmetry and, more importantly, the rather large observed deviations from this rule result from small isospin breaking. This analysis lends support to the possibility that the enhancement phenomenon observed in low energy weak interactions may be systematically described by mirror matter admixtures in ordinary hadrons.
THE SUPERPOSITION APPROXIMATION: A CRITICAL REVIEW
Authors: GROUBA V. D. , ZORIN A. V. , SEVASTIANOV L. A.
Published: March 2004

We have examined the superposition approximation introduced by J. G. Kirkwood. One discusses the origin of mistakes when using this approximation for calculating structural and thermodynamic properties of systems.
ELECTRON–PHONON INTERACTION EFFECTS ON THIRD-HARMONIC GENERATION IN CYLINDRICAL QUANTUM WIRES
Authors: YU YOU-BIN , GUO KANG-XIAN
Published: March 2004

The influence of electron–phonon interaction on third-harmonic generation in cylindrical quantum wires are investigated. The third-harmonic generation coefficient is obtained using compact-density-matrix approach and iterative method, and the numerical results are presented for GaAs cylindrical quantum wires. The results show that the third-harmonic generation coefficient is greatly enhanced after taking into consideration the influence of electron–phonon interaction. It is about thirty times larger than that obtained by just considering electron states when electron–phonon resonance is met.
ATOMIC ENVIRONMENT CHANGES INDUCED BY IRON ADDITION TO GALLIUM BISMUTHATE GLASSES
Authors: SIMON V. , BARZǍ L. , SIMON S. , CHIUZBǍIAN S. G. , NEUMANN M.
Published: March 2004

Atomic environment of x Fe 2 O 3·(80-x) Bi 2 O 3·20 Ga 2 O 3 heavy glasses (0≤x≤20 mol %) was investigated with respect to electronic structure of the samples. Data obtained from Bi 4f, Ga 2p, Fe 2p, and O 1s core-level photoelectron spectra indicate changes in the local order on the account of partial substitution of bismuth by iron. The bismuth cations behave essentially as network formers while the iron and gallium ones acts as network modifiers. The number of nonbridging oxygens depends on Fe 2 O 3 content.
IR AND RAMAN SPECTROSCOPIC INVESTIGATIONS OF Cr2O3-TeO2-B2O3-PbO GLASSES
Authors: ARDELEAN I. , MUREŞAN N. , PǍŞCUŢǍ P.
Published: March 2004

Glasses of the x Cr 2 O 3·(100-x)[70 TeO 2·25 B 2 O 3·5 PbO ] system, with 0≤x≤20 mol %, were prepared and investigated by infrared and Raman spectroscopies in attempt to determine the local structure of glasses. The results shown that BO 3 and BO 4 are the main structural units of the glass system and the chromium ions are located in the network. It is evidenced the presence of TeO 3 and TeO 4 units as possible structural units in our glasses.
DENSE PACKING
Authors: HAUCK J. , MIKA K.
Published: March 2004

Phyllotaxis of plant organs, bacterial ordering and animal coat patterns are analyzed for homogeneity and density. The patterns are approximated by 15 tiles and characterized by the self-coordination numbers T1, T2, T3 of the nearest, next-nearest and third neighbors of the vertices of the tiles. Homogeneous structures with integer Ti values and maximum densities are obtained for distichous, whorled or spiral growth of leaves. Similar T1 values, such as T1=5 and 6 of sunflower seeds or bacteriae, give rise to maximum density. Inhomogeneous structures like the striped patterns of zebras with T1=1, 2 and 3 connections have a higher density than homogeneous stripes with T1=2. Maximum density is also obtained in icosahedral viruses.
ENERGY BAND-GAPS OF MgxZn1-xSe: VIOLATION OF VEGARD'S LAW
Authors: CHARIFI Z. , BAAZIZ H. , BOUARISSA N.
Published: March 2004

Based on a pseudopotential scheme, the composition dependence of energy band-gaps of zinc-blende Mg x Zn 1-x Se ternary alloys in the composition range of 0≤x≤1 are determined. The effect of deviation of lattice constants of the alloys of interest from Vegard's law on the optical bowing parameter and system transition between the direct and indirect structures is discussed.
THE GROWTH OF MnSi1.73 PREPARED BY SPARK PLASMA SINTERING
Authors: WANG ZHIMIN , WU YIDONG , HE YUANJIN
Published: March 2004

Crystals of MnSi 1.73 were prepared by Spark Plasma Sintering (SPS) technique, analyzed by X-ray diffraction (XRD), and invested by metalogragh and scanning electron microscopy (SEM). The growth processes of the samples were studied. It was found that the Mn–Si powders partly formed MnSi 1.73 crystals at 912–937 K under the mechanical pressure of 20 MPa in low vacuum (about 5.0 Pa), and fully formed MnSi 1.73 crystals after sintered at 1173 K for 15 minutes under 40 MPa.
UNIFIED MODEL OF SUPERCONDUCTIVITY OF SINGLET-PAIR Cu OXIDE SUPERCONDUCTOR AND TRIPLET-PAIR Ru OXIDE SUPERCONDUCTOR
Authors: SUGAHARA M. , BOGOLUBOV N. N.
Published: March 2004

A discussion is made on the appearance of strong effective magnetic field with a new quantum state induced by the zero-point plasma oscillation in semi-localized half-filling electron system in the 2D network of circular molecular orbits. With the help of numerical calculation we study the appearance of superconductivity in the Cu and Ru oxide superconductor employing the field-induced quantum state and a gauge-field pairing model, and succeed in giving a unified explanation to the two apparently different types of oxide superconductivity. It is found that in the Cu oxide superconductor singlet pairing of d x2-y2 symmetry occurs in each CuO 2 layer at the decoupling of the zero-spin-sum singlet FQHE state [Formula: see text] by small carrier doping, while in the Ru oxide superconductor triplet electron pairing is caused by two neighboring RuO 2 layers at the decoupling of the spin-polarized FQHE Ψ1,1,1 state where the pairs have d 3z2-r2 symmetry with horizontal node on the Fermi surface. Numerical calculation gives critical temperature consistent with experimental observation.
CRITICAL PROPERTIES AND DISTRIBUTIONS OF TWO-DIMENSIONAL BOSE–EINSTEIN CONDENSATION
Authors: HU GUANG-XI , YE JI-PING , DAI JI-XIN , EVENSON W. E. , DAI XIAN-XI
Published: March 2004

By studying the critical properties of a 2D Bose–Einstein condensation (BEC) in traps, we obtain the accurate analytic expressions of transition temperature, condensed fraction, and specific heat. The analytic results fit in fairly well with numerical results. We find that an isotropical potential favors most for condensation to occur. With the aid of Bloch summation, we study the distributions of coordinates and momenta of the system. Some clear physical pictures are presented.
DISORDER-TUNABLE PHOTONIC PROPERTIES OF PERIODIC DIELECTRIC/METAL SUPERLATTICES
Authors: SOTO-PUEBLA DIEGO , RAMOS-MENDIETA FELIPE , XIAO MUFEI
Published: March 2004

Influences of perturbative disorders to the photonic properties of one-dimensional periodic dielectric/metal superlattices have been numerically studied. In the calculations, two different disorders were considered, i.e. the disorder in position and in thickness of the metallic layers. Significant modifications induced by the disorders have been found in the photonic band structures. The modifications vary according to the type as well as the degree of the disorders. Both enhanced and attenuated transmissions have been observed in the photonic band gap. Detailed discussions on the calculated photonic band structures would provide useful information on how to obtain desired photonic band structures by introducing certain disorders.
INTEGRATION BY PARTS AND SMOOTHNESS OF THE LAW FOR A CLASS OF STOCHASTIC EVOLUTION EQUATIONS
Authors: BONACCORSI STEFANO , FUHRMAN MARCO
Published: March 2004

We consider a Markov process X in a Hilbert space H, solution of a semilinear stochastic evolution equation driven by an infinite-dimensional Wiener process, occurring in the equation as an additive noise. Using techniques of the Malliavin calculus, under suitable assumptions, we prove an integration by parts formula for the transition probabilities νt, t>0 (the laws of Xt). We deduce results on differentiability (i.e. existence of logarithmic derivatives) of νt along a set of directions h∈H which can be described in terms of the coefficients of the equation. The general results are then applied to various classes of non linear stochastic partial differential equations and systems.
UNITARITY OF KUO'S FOURIER–MEHLER TRANSFORM
Authors: JI UN CIG , OBATA NOBUAKI
Published: March 2004

Kuo's Fourier–Mehler transforms {ℱΘ} form a one-parameter automorphism group of the space of white noise distributions [Formula: see text]. The adjoint transforms [Formula: see text] form a one-parameter automorphism group of the space of test white noise functions [Formula: see text] but do not admit unitary extensions with respect to the L2-norm induced from the Gaussian measure with variance 1. We prove that [Formula: see text] admits an extension to a one-parameter group of unitary operators on the L2-space with respect to the Gaussian measure with variance 1/2.
LOGARITHMIC SOBOLEV INEQUALITY FOR $H_0^s$-METRIC ON PINNED LOOP GROUPS
Authors: INAHAMA YUZURU
Published: March 2004

In this paper we prove the logarithmic Sobolev inequality on pinned loop groups over compact Lie groups equipped with [Formula: see text]-metric (s>1/2). We also compute the Ricci tensor with respect to [Formula: see text]-metric and investigate its asymptotic behavior as s decreases to 1/2.
Λ-FREE PROBABILITY
Authors: MŁOTKOWSKI WOJCIECH
Published: March 2004

We introduce and study a notion of Λ-freeness, which generalises both freeness and independence in the context of noncommutative probability. In particular, we extend Voiculescu's construction of the free product of representations of unital *-algebras. A central limit theorem is also proved.
GENERAL SOLUTION OF THE FUNCTIONAL CENTRAL LIMIT PROBLEMS ON A LIE GROUP
Authors: PAP GYULA
Published: March 2004

Starting with an array (μn,ℓ)n,ℓ∈ℕ of probability measures on a Lie group G, one forms the convolution products μn(s,t):=μn,kn(s)+1*⋯*μn,kn(t), 0≤s≤t, where kn:ℝ+→ℤ+ are increasing scaling functions. Sufficient conditions are established for convergence μn(s,t)→μ(s,t) as n→∞, where (μ(s,t))0≤s≤t is necessariliy a convolution hemigroup, i.e. μ(s,t)=μ(s,r)*μ(r,t), 0≤s≤r≤t. Using previous results concerning convolution hemigroups of finite variation (Heyer and Pap9), this leads to a bijection between the set of convolution hemigroups and an appropriate parameter set containing time-dependent Lévy–Khinchin type triplets. Hence, at the same time, we parametrize the set of measures generated by stochastically continuous processes with independent left increments in G. The above-mentioned sufficient conditions turn out to be necessary and sufficient for convergence of a sequence of random step functions corresponding to the triangular array towards a stochastically continuous process with independent left increments. Connections with results of Feinsilver4 and Kunita11 are discussed.
Differential requirement of members of the MAPK family for CCL2 expression by hepatic stellate cells
Authors: Marra Fabio , Delogu Wanda , Petrai Ilaria , Pastacaldi Sabrina , Bonacchi Andrea , Efsen Eva , Aleffi Sara , Bertolani Cristiana , Pinzani Massimo , Gentilini Paolo
Published: March 2004

Hepatic stellate cells (HSC) coordinate the liver wound-healing response through secretion of several cytokines and chemokines, including CCL2 (formerly known as monocyte chemoattractant protein-1). In this study, we evaluated the role of different proteins of the MAPK family (ERK, p38MAPK, and JNK) in the regulation of CCL2 expression by HSC, as an index of their proinflammatory activity. Several mediators activated all three MAPK, including TNF, IL-1, and PDGF. To assess the relative role of the different MAPKs, specific pharmacological inhibitors were used; namely, SB203580 (p38MAPK), SP600125 (JNK), and PD98059 (MEK/ERK). The efficacy and specificity of the different inhibitors in our cellular system were verified analyzing the enzymatic activity of the different MAPKs using in vitro kinase assays and/or testing the inhibition of phosphorylation of downstream substrates. SB203580 and SP600125 dose-dependently inhibited CCL2 secretion and gene expression induced by IL-1 or TNF. In contrast, inhibition of ERK did not affect the upregulation of CCL2 induced by the two cytokines. Finally, activin A was also found to stimulate CCL2 expression and to activate ERK, JNK, p38, and their downstream targets. Unlike in cells exposed to proinflammatory cytokines, all three MAPKs were required to induce CCL2 secretion in response to activin. We conclude that members of the MAPK family differentially regulate cytokine-induced chemokine expression in human HSC.
Different responsiveness of excitatory and inhibitory enteric motor neurons in the human esophagus to electrical field stimulation and to nicotine
Authors: González Asensio A. , Farré Ricard , Clavé Pere
Published: March 2004

To compare electrical field stimulation (EFS) with nicotine in the stimulation of excitatory and inhibitory enteric motoneurons (EMN) in the human esophagus, circular lower esophageal sphincter (LES), and circular and longitudinal esophageal body (EB) strips from 20 humans were studied in organ baths. Responses to EFS or nicotine (100 μM) were compared in basal conditions, after NG-nitro-l-arginine (l-NNA; 100 μM), and after l-NNA and apamin (1 μM). LES strips developed myogenic tone enhanced by TTX (5 μM) or l-NNA. EFS-LES relaxation was abolished by TTX, unaffected by hexamethonium (100 μM), and enhanced by atropine (3 μM). Nicotine-LES relaxation was higher than EFS relaxation, reduced by TTX or atropine, and blocked by hexamethonium. After l-NNA, EFS elicited a strong cholinergic contraction in circular LES and EB, and nicotine elicited a small relaxation in LES and no contractile effect in EB. After l-NNA and apamin, EFS elicited a strong cholinergic contraction in LES and EB, and nicotine elicited a weak contraction amounting to 6.64 ± 3.19 and 9.20 ± 5.51% of that induced by EFS. EFS elicited a contraction in longitudinal strips; after l-NNA and apamin, nicotine did not induce any response. Inhibitory EMN tonically inhibit myogenic LES tone and are efficiently stimulated both by EFS and nicotinic acetylcholine receptors (nAChRs) located in somatodendritic regions and nerve terminals, releasing nitric oxide and an apamin-sensitive neurotransmitter. In contrast, although esophageal excitatory EMN are efficiently stimulated by EFS, their stimulation through nAChRs is difficult and causes weak responses, suggesting the participation of nonnicotinic mechanisms in neurotransmission to excitatory EMN in human esophagus.
Perturbations in homocysteine-linked redox homeostasis in a murine model for hyperhomocysteinemia
Authors: Vitvitsky Victor , Dayal Sanjana , Stabler Sally , Zhou You , Wang Hong , Lentz Steven R. , Banerjee Ruma
Published: March 2004

Elevated plasma levels of homocysteine are a risk factor for cardiovascular diseases, neural tube defects, and Alzheimer's disease. The transsulfuration pathway converts homocysteine to cysteine, and ∼50% of the cysteine in glutathione is derived from homocysteine in human liver cells, which suggests the hypothesis that defects in the transsulfuration pathway perturb redox homeostasis. To test this hypothesis, we examined a murine model for hyperhomocysteinemia in which the gene encoding the first enzyme in the transsulfuration pathway, cystathionine β-synthase (CBS), has been disrupted. Limited metabolite profiling and CBS expression studies in liver, kidney, and brain reveal tissue-specific differences in the response to Cbs disruption. Homozygous disruption of Cbs lowered cysteine concentration in all three organs. Glutathione concentration was diminished in liver and brain, thus affecting the redox buffering capacity in these organs, whereas the approximately twofold higher glutathione synthesis capacity in kidney helped preserve the glutathione pool size despite loss of the transsulfuration pathway in this organ. In contrast, disruption of a single Cbs allele elicited only minor redox perturbations. Furthermore, the Cbs+/− genotype did not confer a significant disadvantage compared with the Cbs+/+ genotype in hepatocytes challenged by oxidative stress from exposure to tertiary butylhydroperoxide. These studies provide evidence that homozygous disruption of Cbs perturbs redox homeostasis and reduces cysteine levels, raising the possibility that these changes may be important in the etiology of the clinical manifestations of CBS deficiency.