bluuebunny/crossref_metadata_2025 huggingface dataset:
Burr Height in Shear Slitting of Aluminum Webs
Authors: Ma Jin , Lu Hongbing , Li Ming , Wang Bo
Published: February 2006

Continuous shear slitting of aluminum sheets (or webs) was investigated using a laboratory slitter. This study focused on experimental investigation of the effect of three major slitting parameters (clearance, overlap, and cant angle) on the burr height. It was found that there exists a critical clearance in shear slitting of aluminum webs; using a clearance higher than the critical value leads to unacceptable burr height. The blade overlap must be within a certain range; using an overlap below the lower bound of this range will not enable the cut of a web, and utilizing an overlap higher than the upper bound of the range produces high burrs. A relatively large cant angle produces good slit edge quality but at the expense of the blade service life; a relatively small cant angle gives reasonable edge quality while maintaining a reasonable blade service life. Based on results on burr height for four aluminum webs, a relation linking the critical clearance to the slitting parameters and the web properties is presented. This can be used for selection of an appropriate clearance to produce good slit edge and low burr height for a given aluminum web.
Numerical Simulation of Machined Surface Topography and Roughness in Milling Process
Authors: Gao Tong , Zhang Weihong , Qiu Kepeng , Wan Min
Published: February 2006

Machined surface topography is very critical since it directly affects the surface quality, especially the surface roughness. Based on the trajectory equations of the cutting edge relative to the workpiece, a new method is developed for the prediction of machined surface topography. This method has the advantage of simplicity and is a mesh-independent direct computing method over the traditional interpolation scheme. It is unnecessary to discretize the cutting edge or to mesh the workpiece. The topography value of any point on the machined surface can be calculated directly, and the spindle runout can be taken into account. The simulation of machined surface topography is successfully carried out for both end and ball-end milling processes. In the end milling process, a fast convergence of solving the trajectory equation system by the Newton-Raphson method can be ensured for topography simulation at any node on the machined surface thanks to the appropriate choice of the starting point. In the ball-end milling process, this general algorithm is applicable to any machined surface. Finally, the validity of the method is demonstrated by several simulation examples. Simulation results are compared to experimental ones, and a good agreement is obtained.
Using the Eigenvalues of Multivariate Spectral Matrices to Achieve Cutting Direction and Sensor Orientation Independence
Authors: Roth John T.
Published: February 2006

There is a strong need for monitoring techniques capable of tracking the health of cutting tools under varying conditions. Unfortunately, most monitoring techniques are dependent on the cutting direction and/or the sensor orientation, limiting their effectiveness in the typical industrial environment. With this in mind, this research develops a monitoring technique that is independent of both of these factors. This is accomplished by using multivariate autoregressive models that are fit to the output from a triaxial accelerometer. The work shows that the eigenvalues of multivariate spectral matrices, calculated at the machining frequencies, are not only sensitive to the condition of the tool but are also independent of the direction of cutting and the orientation of the sensor. This independence is verified experimentally through tests conducted under a variety of cutting directions and sensor orientations.
Active Control of Regenerative Chatter During Metal Cutting Process
Authors: Mei C. , Cherng J. G. , Wang Y.
Published: February 2006

Chatter, a violent relative vibration between a workpiece and a cutting tool, is a frequent problem in a machining operation. Among the many factors which contribute to the problem, regenerative chatter is found to be the most detrimental. Optimal control is designed for suppressing regenerative chatter with the critical regenerative effect taken into account. Furthermore, a novel hybrid time and frequency domain approach is developed for generating the stability lobe diagram for the dynamic system after control, since the conventional frequency domain approach is no longer feasible. Numerical results are obtained in both time and frequency domain for verifying the effectiveness of the controller as well as the hybrid approach for generating the stability lobe diagram.
Development of Hardware Simulator and Controller for Web Transport Process
Authors: Kim Jeetae
Published: February 2006

In this study a hardware simulator and controller for web transport process are developed. First the dynamics of web transport process is analyzed for simulator and controller design. An example Polypropylene transport process is investigated and its simplified transport model is derived. Then the web transport process simulator and its controller are developed. Accurate tension force control is needed to produce high quality web formed materials. The process controller uses the loadcell as a tension measuring device and closed-loop control is used for tension force regulation. The response of the system is tested under the disturbances in tension and the experimental results show that the system regulates tension disturbances properly.
Isopropyl N-Arylmalonamates. Synthesis, Structure, Conformation and Reactions with Carbon Disulfide
Authors: Rudorf Wolf-Dieter , Loos Dušan , Wybraniec Joanna , Prónayová Naďa , Gawinecki Ryszard , Šusteková Zora
Published: February 2006

Acylation of aromatic amines 1 with diisopropyl malonate (2) leads to a mixture of isopropyl N-arylmalonamates 3 and malonanilides 4. The reaction of 3 with carbon disulfide in the presence of sodium hydride gives disodium salts 5. Treatment of 5 with an alkylating agent yields the open-chain or cyclic ketene dithioacetals 6, 7 or 8. The molecular structure, hydrogen bonding and preferential conformation of the isopropyl N-arylmalonamates 3, 6 and 7 were investigated using correlation analyses of IR, 13C NMR and AM1 semiempirical data.
Tricyclic Purine Analogs Derived from 2-Amino-6-chloropurine and 2,6-Diaminopurine and Their Methylated Quaternary Salts
Authors: Hořejší Kateřina , Pohl Radek , Holý Antonín
Published: February 2006

A novel series of tricyclic, etheno-bridged purine analogs was sythesized from 2-amino-6-(substituted amino)-9-methylpurines by cyclization with chloroacetaldehyde, with particular focus on the regioselectivity of the cyclization reaction and fluorescence properties. The analogs as well as the starting purines were alkylated with iodomethane, affording a new class of quaternary salts with potential biological activity. Neither significant fluorescence nor cytostatic effect was found.
Comparative investigations of T cell receptor γ gene rearrangements in frozen and formalin-fixed paraffin wax-embedded tissues by capillary electrophoresis
Authors: Christensen M , Funder A D , Bendix K , Soerensen F B
Published: February 2006

Aim:To compare clonal T cell receptor γ (TCRγ) gene rearrangements in frozen and formalin-fixed paraffin wax-embedded (FFPE) tissue, using capillary electrophoresis for use in diagnostics, as T cell lymphomas may be difficult to diagnose by conventional methods.

Methods:The DNA for PCR was extracted from frozen and FFPE tissue, cell lines and blood. PCR primers Vγ1-8, Vγ9, Vγ10 or Vγ11 (5′ end labelled) combined with a mixture of JγP1/JγP/JγP2/Jγ2 (unlabelled) were used. Monoclonal cases were sequenced and clonality, reproducibility, sensitivity and specificity analyses were carried out.

Results:In all cases the molecular test was found to be in agreement with the histological diagnosis. Discrepancies were found between frozen and FFPE tissue in 18 of 56 (32%) tests. The method was highly reproducible. The sensitivity was found to be 0.5% for cell lines and 1% for patient specimens and the specificity 100%. The junctional region between the Vγ and Jγ segments was specific for each patient.

Conclusions:Capillary electrophoresis of PCR products from frozen and FFPE tissue is suitable for detecting clonal TCRγ gene rearrangements. It is important, however, to correlate the results with conventional morphological and immunohistochemical studies.
Expression of glucocorticoid receptors in non-neoplastic lymphoid follicles and B cell type malignant lymphomas
Authors: Okazaki S-I , Yamakawa M , Maeda K , Ohta N , Aoyagi M
Published: February 2006

Objective:To evaluate the expression of human glucocorticoid receptors (hGRs), such as hGR (4H2), hGR-α, and hGR-β, in non-neoplastic lymphoid follicles and B cell type malignant lymphomas.

Methods:The expression of hGRs in non-neoplastic lymphoid follicles and malignant lymphomas, including diffuse large cell lymphoma, mantle cell lymphoma, and follicular lymphoma, was examined immunohistochemically. HGR (4H2) expression was confirmed by double immunostaining of tissues and in isolated cells from tonsillar germinal centres, and by immunoelectronmicroscopy.

Results:In secondary lymphoid follicles of any non-neoplastic diseases—such as chronic tonsillitis, reactive lymphadenitis, and Kimura’s disease—the germinal centre cells often expressed hGR (4H2) and hGR-α. Double immunocytochemical staining of isolated germinal centre cells showed that the majority of hGR (4H2) positive cells were CD20 positive B cells, and that follicular dendritic cells also expressed hGR. Immunoelectronmicroscopy revealed the presence of nuclear hGR (4H2) in the binucleated follicular dendritic cells and germinal centre cells. The frequency of hGR (4H2) expression in diffuse large B cell lymphoma was higher, that in mantle cell lymphoma was lower, and that in follicular lymphoma was intermediate among the types of malignant lymphoma. The hGR (4H2) expression was less frequent in cases of grade I follicular lymphoma.

Conclusions:There are differences in hGR expression between the germinal centre and the mantle zone in non-neoplastic lymphoid follicles, and differences of hGR (4H2) expression among the types of malignant lymphoma and grades of follicular lymphoma, which probably contribute to the different steroid sensitivities.
Optimising preoperative diagnosis in phyllodes tumour of the breast
Authors: Jacklin R K , Ridgway P F , Ziprin P , Healy V , Hadjiminas D , Darzi A
Published: February 2006

The role of the pathologist in the preoperative diagnosis of phyllodes tumours of the breast is critical to appropriate surgical planning. However, reliable differentiation of phyllodes tumour from cellular fibroadenoma remains difficult. Preoperative diagnostic accuracy allows correct surgical treatment, avoiding the pitfalls of reoperation because of inadequate excision, or surgical overtreatment. Specific clinical indices may arouse diagnostic suspicion but are unreliable for confirmation, as with current imaging modes. Fine needle aspiration cytology has a high false negative rate. Few studies have evaluated the role of core needle biopsy, but it may prove a useful adjunct. Both diagnostic and prognostic information may in future be gained from application of immunohistochemical and other techniques assessing the expression of proliferative markers including p53, Ki-67, and others.
Numerical transformation of geochemical data: 1. Maximizing geochemical contrast to facilitate information extraction and improve data presentation
Authors: Stanley Clifford R.
Published: February 2006

Data transformation in geoscience has typically been motivated by three objectives: (1) creating normally distributed data; (2) creating data that are additive; and (3) making errors constant across the range of the data.

Historically, transformation of geochemical concentrations has been undertaken to achieve normality. Unfortunately, most geochemical distributions are multi-modal and derived from several geological sources. Thus no continuous, monotonic transformations exist that can convert these into (even approximately) normal distributions, and thus transformation for this purpose is neither generally achievable nor justified. Transformations that create additivity are rare in geochemical applications, although they are important in error treatment and lithogeochemical data analysis. These transformations effectively convert data into a form that can be sensibly manipulated, and thus facilitate subsequent data analysis. Transformation to stabilizing errors in geochemical data is also not common, although it is a useful attribute in subsequent geochemical data analysis.

Another type of data transformation, designed to maximize geochemical contrast (or maximize data variance), may be achieved by raising geochemical concentrations to a power after transforming the data to the 0 ↔ 1 interval. The power that produces the maximum variance in the transformed result creates the maximum geochemical contrast, affording the geochemist an opportunity to extract the most information from the geochemical data.

The ‘maximum data variance’ transformation is based not on the subsequent data analysis result (e.g. recognizable geochemical patterns; circular reasoning where ‘the end justifies the means’), but on an optimal property created by the transform. As a result, this transformation provides significant advantage in subsequent data analysis because results achieved are not subjective.
Numerical transformation of geochemical data: 2. Stabilizing measurement error to facilitate data interpretation
Authors: Stanley Clifford R.
Published: February 2006

Traditional uses of data transformations in geoscience have typically been motivated by three objectives: (1) creating normally distributed data; (2) creating data that are additive; and (3) making errors constant across the data range. Part 1 of this paper discussed the transformation applicability for the first two reasons in geochemical applications, and introduced a fourth motivation whereby transformation maximizes the variance (or geochemical contrast) in the transformed data; it did not discuss transformation to stabilize measurement error.

Although transformation to stabilizing errors in geochemical data is not common, this is a useful attribute in geochemical data analysis. The transformation is dependent on the model describing the magnitude of measurement (sampling and analysis) error as a function of concentration. Models describing measurement error as a function of concentration can be used to derive a transformation that will stabilize the measurement error in the transformed variable. Poisson, binomial and hypergeometric models are typically used to describe sampling errors, whereas straight line (constant, proportional and affine) models are used to describe analytical errors. The associated variance stabilizing transformations, derived from these models, have constant propagated errors. As a result, these transformations create a ‘level playing field’ for subsequent data analysis, enabling the discovery of additional information in the data.

Homoscedastic measurement error allows the geochemist to justify use of a specific transformation based not on the subsequent data analysis results (circular reasoning; ‘the end justifies the means’), but on optimal properties created by the transformation. In this way, objective results can be achieved scientifically, providing another motivation to collect geochemical quality control data.
A system model for the origin and evolution of the Tono Uranium Deposit, Japan
Authors: Metcalfe Richard , Takase Hiroyasu , Sasao Eiji , Ota Kunio , Iwatsuki Teruki , Arthur Randolph C. , Stenhouse Michael J. , Zhou Wei , Mackenzie Angus B.
Published: February 2006

Data from the Tono Uranium Deposit of central Japan were used to develop an improved approach for simulating uranium migration and retardation, while taking into account both long-term environmental changes and uncertainties in data. Based upon extensive field and laboratory investigations, conceptual and numerical models for environmental perturbations, including uplift, subsidence and faulting, were constructed. Model development was based on a novel adaptation of a safety assessment methodology that previously has been applied to radioactive waste repositories. A ‘reference scenario’ was developed using a systems analysis approach. This scenario is a best estimate of how the geological system and the uranium deposit reached their present states and includes descriptions of all major environmental perturbations. Uranium is mobilized from the uppermost Toki granite under relatively oxidizing conditions, and is then transported by groundwater into overlying sedimentary rocks. There, reducing conditions promote uranium deposition. A specially designed numerical model simulated the main features of this scenario. Many simulations were performed to identify key uncertainties to which the timing of ore deposition and uranium distribution are sensitive. A key finding is that retardation of U by processes other than precipitation of discrete U minerals, most probably sorption on solid phases, contributes significantly to the stability of the ore deposit. Sorption could potentially be important for confining the U within the sedimentary rocks in spite of environmental changes such as exhumation and seismic pumping. The approach could be used elsewhere, to assess the safety of deep geological high-level radioactive waste (HLW) disposal. A related application would be at potential future waste disposal sites, to prioritize site characterization so that the most safety-relevant uncertainties are reduced. There are also possible applications in other fields, most notably to assess the implications of alternative ore genetic models.
Geochemical constraints on the origin and stability of the Tono Uranium Deposit, Japan
Authors: Arthur Randolph C. , Iwatsuki Teruki , Sasao Eiji , Metcalfe Richard , Amano Kenji , Ota Kunio
Published: February 2006

Data characterizing the mineralogy, hydrochemistry and geomicrobiology of the Tono region of central Japan were used to interpret geochemical constraints on the origin and stability of the Tono Uranium Deposit. The derived constraints are compatible with models of deposit formation, which call for leaching of uranium from the upper weathered zone of the Toki Granite by relatively oxidizing groundwaters that are near-neutral to moderately alkaline and carboniferous. The oxidizing groundwaters then migrate into mudstones and sandstones of the overlying Toki Formation, where the uranyl species is reduced by water–rock–microbe interactions to uranous species, sorbed by various detrital and authigenic phases and eventually precipitated as uraninite, coffinite and the metastable, amorphous hydrous oxide, UO
2
(
am
).

Formation of the Tono deposit may have been more or less continuous up to the present time. The modern hydrochemical system, upon which the genetic model is based, began to evolve about 15 Ma when seawater was flushed out of the sedimentary cover and basement granite by fresh, meteoric waters during a period of uplift and erosion preceding Pliocene to Pleistocene sedimentation. Recharge with meteoric water continued to the present, which suggests that palaeohydrochemical conditions were probably similar to those observed in the region today when the Tono deposit began to form about 10 Ma.

Redox environments in the Tono region inferred from
in-situ
Eh measurements in deep boreholes and calculated potentials for the SO
4
2−
/HS
−
redox couple appear to be controlled by heterogeneous reactions involving Fe(III)-oxyhydroxides. Metastable equilibria and particle-size effects associated with these reactions produce a range of possible redox environments that are equally compatible with both the relatively oxidizing and reducing groundwaters of the Toki Granite. This compatibility extends to sedimentary porewaters, where the redox environment is also controlled by microbially mediated sulphate reduction, oxidation of organic matter and precipitation of sulphide minerals. Redox conditions have been stable during at least the past several tens of thousands of years based on palaeoredox indicators interpreted from the trace element contents of fracture calcites. The pH and carbonate contents of palaeogroundwaters and modern groundwaters of the Tono region were, and are, controlled mainly by calcite equilibrium.
An overview of a natural analogue study of the Tono Uranium Deposit, central Japan
Authors: Sasao Eiji , Ota Kunio , Iwatsuki Teruki , Niizato Tadafumi , Arthur Randolph C. , Stenhouse Michael J. , Zhou Wei , Metcalfe Richard , Takase Hiroyasu , Mackenzie Angus B.
Published: February 2006

The basic concept of deep geological disposal of high-level radioactive waste is to isolate the waste from the human environment for the long term. Because the Japanese islands are located in a geologically active area, geological phenomena such as exhumation and fault activity must be considered by any safety assessment connected with deep geological disposal. The Tono Uranium Deposit, central Japan, has been affected by such geological phenomena during the interval since its formation, and so it is a suitable analogue for evaluating how this might be done.

The present natural analogue study of the Tono Uranium Deposit (Tono Natural Analogue Project) was started in 2001 with the main aim of studying a so-called ‘worst-case scenario’ for performance assessment (PA). The project involved characterizing the geology, hydrogeology, geochemistry and microbiology of the deposit and obtaining quantitative information about specific times in the past, as a means for developing, and building confidence in, conceptual and numerical models.

This project applied systems analysis, which has been widely undertaken in PAs of deep geological isolation. Systems analysis involves a systematic identification, classification and screening of features, events and process (FEPs) that occur or have occurred in and around the deposit. Based on the site data, important FEPs were identified.
Characterization and geochemical behaviour of uranium series nuclides in sandy sediments at Kanamaru area, Yamagata and Niigata Prefectures, Japan
Authors: Kanai Yutaka , Kamioka Hikari , Nakajima Terumasa , Tsukamoto Hitoshi
Published: February 2006

Uranium series nuclides in the Tertiary arkosic sands from a high rainfall area in Japan were determined and their characteristics and behaviour were studied. Uranium was concentrated in the upper (
c.
241 ppm) and lower (
c.
581 ppm) layers although no specific U mineral was observed. The filtration experiment showed that U in the groundwater is in the dissolved form rather than colloidal or particulate forms. Most U in the concentrated layers was in easily soluble fractions (such as AcONa/AcOH soluble) while the U content in the water around the site was low. The fact that the
230
Th/
234
U activity ratios of a sample in the upper layer were much greater than unity suggests that U migration occurred within 0.3 Ma. However, the
234
U/
238
U and
230
Th/
234
U activity ratios of samples in the lower layer were close to unity, suggesting that the material has not been strongly leached. Using chemical leaching techniques, a small disequilibrium among the fractions is observed, even though the bulk sample was near equilibrium. It is inferred that sorption of U is more effective than precipitation in this area.
PEPTIDE HORMONES IN PLANTS
Authors: Matsubayashi Yoshikatsu , Sakagami Youji
Published: February 2006

In recent years, numerous biochemical and genetic studies have demonstrated that peptide signaling plays a greater than anticipated role in various aspects of plant growth and development. A substantial proportion of these peptides are secretory and act as local signals mediating cell-to-cell communication. Specific receptors for several peptides were identified as being membrane-localized receptor kinases, the largest family of receptor-like molecules in plants. These findings illustrate the importance of peptide signaling in the regulation of plant growth, functions that were previously ascribed to the combined action of small lipophilic compounds referred to as “traditional plant hormones.” Here, we outline recent advances in the current understanding of biologically active peptides in plants, currently regarded as a new class of plant hormones.
VITAMIN SYNTHESIS IN PLANTS: Tocopherols and Carotenoids
Authors: DellaPenna Dean , Pogson Barry J.
Published: February 2006

Carotenoids and tocopherols are the two most abundant groups of lipid-soluble antioxidants in chloroplasts. In addition to their many functional roles in photosynthetic organisms, these compounds are also essential components of animal diets, including humans. During the past decade, a near complete set of genes required for the synthesis of both classes of compounds in photosynthetic tissues has been identified, primarily as a result of molecular genetic and biochemical genomics-based approaches in the model organisms Arabidopsis thaliana and Synechocystis sp. PCC6803. Mutant analysis and transgenic studies in these and other systems have provided important insight into the regulation, activities, integration, and evolution of individual enzymes and are already providing a knowledge base for breeding and transgenic approaches to modify the types and levels of these important compounds in agricultural crops.
THE GENETICS AND BIOCHEMISTRY OF FLORAL PIGMENTS
Authors: Grotewold Erich
Published: February 2006

Three major groups of pigments, the betalains, the carotenoids, and the anthocyanins, are responsible for the attractive natural display of flower colors. Because of the broad distribution of anthocyanins (synthesized as part of the flavonoid pathway) among the flowering plants, their biosynthesis and regulation are best understood. However, over the past few years, significant progress has been made in understanding the synthesis and participation of carotenoids (derived from isoprenoids) and betalains (derived from tyrosine) in flower pigmentation. These three families of pigments play important ecological functions, for example in the attraction of pollinating animals. Anthocyanins in particular have also been the target of numerous biotechnological efforts with the objective of creating new, or altering the properties of existing, coloring compounds. The focus of this review is to examine the biosynthesis, regulation, and contribution to flower coloration of these three groups of pigments.
PLASTID-TO-NUCLEUS RETROGRADE SIGNALING
Authors: Nott Ajit , Jung Hou-Sung , Koussevitzky Shai , Chory Joanne
Published: February 2006

Plant cells store genetic information in the genomes of three organelles: the nucleus, plastid, and mitochondrion. The nucleus controls most aspects of organelle gene expression, development, and function. In return, organelles send signals to the nucleus to control nuclear gene expression, a process called retrograde signaling. This review summarizes our current understanding of plastid-to-nucleus retrograde signaling, which involves multiple, partially redundant signaling pathways. The best studied is a pathway that is triggered by buildup of Mg-ProtoporphyrinIX, the first intermediate in the chlorophyll branch of the tetrapyrrole biosynthetic pathway. In addition, there is evidence for a plastid gene expression-dependent pathway, as well as a third pathway that is dependent on the redox state of photosynthetic electron transport components. Although genetic studies have identified several players involved in signal generation, very little is known of the signaling components or transcription factors that regulate the expression of hundreds of nuclear genes.
STRUCTURE AND FUNCTION OF PHOTOSYSTEMS I AND II
Authors: Nelson Nathan , Yocum Charles F.
Published: February 2006

Oxygenic photosynthesis, the principal converter of sunlight into chemical energy on earth, is catalyzed by four multi-subunit membrane-protein complexes: photosystem I (PSI), photosystem II (PSII), the cytochrome b6f complex, and F-ATPase. PSI generates the most negative redox potential in nature and largely determines the global amount of enthalpy in living systems. PSII generates an oxidant whose redox potential is high enough to enable it to oxidize H2O, a substrate so abundant that it assures a practically unlimited electron source for life on earth. During the last century, the sophisticated techniques of spectroscopy, molecular genetics, and biochemistry were used to reveal the structure and function of the two photosystems. The new structures of PSI and PSII from cyanobacteria, algae, and plants has shed light not only on the architecture and mechanism of action of these intricate membrane complexes, but also on the evolutionary forces that shaped oxygenic photosynthesis.
THE ESCRT COMPLEXES: Structure and Mechanism of a Membrane-Trafficking Network
Authors: Hurley James H. , Emr Scott D.
Published: February 2006

The ESCRT complexes and associated proteins comprise a major pathway for the lysosomal degradation of transmembrane proteins and are critical for receptor downregulation, budding of the HIV virus, and other normal and pathological cell processes. The ESCRT system is conserved from yeast to humans. The ESCRT complexes form a network that recruits monoubiquitinated proteins and drives their internalization into lumenal vesicles within a type of endosome known as a multivesicular body. The structures and interactions of many of the components have been determined over the past three years, revealing mechanisms for membrane and cargo recruitment and for complex assembly.
SEARCHING WHERE THE LIGHT SHINES: Studying Democratization in the Middle East
Authors: Anderson Lisa
Published: February 2006

▪ Abstract  For several decades, political scientists who work on the Middle East have been asked by both disciplinary and policy audiences about the region's prospects for democratization. We encounter difficulties in answering that question because it arises from American disciplinary and policy preoccupations, not from regional political dynamics. As a result of those preoccupations, Middle East political scientists have neglected some of the major political forces in the region, while contributing to the development of general comparative theories of democracy and democratization only at the margins.
Whole genome microarray analysis of growth hormone-induced gene expression in bone: T-box3, a novel transcription factor, regulates osteoblast proliferation
Authors: Govoni Kristen E. , Lee Seong Keun , Chadwick Robert B. , Yu Hongrun , Kasukawa Yuji , Baylink David J. , Mohan Subburaman
Published: February 2006

Growth hormone (GH) is important in the development and maintenance of bone; however, the IGF-dependent and -independent molecular pathways involved remain to be established. We used microarray analysis to evaluate GH signaling pathways in 4-wk-old GH-deficient mice following a single injection of GH (4 mg/kg body wt) or PBS ( n = 6/group) at 6 or 24 h after treatment. Six thousand one hundred sixty genes were differentially expressed at P ≤ 0.05, and 17% of these genes were identified at both time points. Several of the genes differentially expressed were expressed sequence tags, and the remaining genes fell into 49 Gene Ontology categories. For subsequent studies, we focused on T-box (Tbx)3, a novel transcription factor, which increased more than twofold at both time points. Real-time RT-PCR analysis determined that pretreatment with IGF-binding protein-4 did not block GH-induced Tbx3 expression in vitro. Pretreatment with TNF-α blocked GH-induced Tbx3 expression. Tbx3 expression increased during osteoblast differentiation and following BMP-7 and Wnt3a treatment ( P ≤ 0.05). Blocking Tbx3 expression by small interfering RNA decreased cell number and [3H]Thymidine incorporation ( P < 0.01). In conclusion, 1) GH caused acute changes in several novel genes, suggesting that many GH-induced signaling pathways and target genes remain to be discovered; 2) because Tbx3 expression is regulated in osteoblasts and blockage of Tbx3 expression decreased cell number and DNA synthesis, we propose that Tbx3 is an important determinant of osteoblast cell number.
Chronic intrauterine pulmonary hypertension selectively modifies pulmonary artery smooth muscle cell gene expression
Authors: Resnik Ernesto , Herron Jean , Keck Maggie , Sukovich David , Linden Bradley , Cornfield David N.
Published: February 2006

Pulmonary artery smooth muscle cell (PASMC) relaxation at birth results from an increase in cytosolic cGMP, cGMP-dependent and kinase-mediated activation of the Ca2+-sensitive K+channel (KCa), and closure of voltage-operated Ca2+channels (VOCC). How chronic intrauterine pulmonary hypertension compromises perinatal pulmonary vasodilation remains unknown. We tested the hypothesis that chronic intrauterine pulmonary hypertension selectively modifies gene expression to mitigate perinatal pulmonary vasodilation mediated by the cGMP kinase-KCa-VOCC pathway. PASMC were isolated from late-gestation fetal lambs that had undergone either ligation of the ductus arteriosus (hypertensive) or sham operation (control) at 127 days of gestation and were maintained under either hypoxic (∼25 Torr) or normoxic (∼120 Torr) conditions in primary culture. We studied mRNA levels for cGMP kinase Iα (PKG-1α), the α-chain of VOCC (Cav1.2), and the α-subunit of the KCachannel. Compared with control PASMC, hypertensive PASMC had decreased VOCC, KCa, and PKG-1α expression. In response to sustained normoxia, expression of VOCC and KCachannel decreased and expression of PKG-1α increased. In contrast, sustained normoxia had no effect on PKG-1α levels and an attenuated effect on VOCC and KCachannel expression in hypertensive PASMC. Protein expression of PKG-1α was consistent with the mRNA data. We conclude that chronic intrauterine pulmonary hypertension decreases PKG expression and mitigates the genetic effects of sustained normoxia on pulmonary vasodilation, because gene expression remains compromised even after sustained exposure to normoxia.
Parallel Encoding of Focus and Interrogative Meaning in Mandarin Intonation
Authors: Liu F. , Xu Y.
Published: February 2006

Despite much research, disagreements abound regarding the detailed charac-teristicsof question intonation in different languages or even in the same language.The present study investigates question intonation in Mandarin by also consideringthe role of focus that is frequently ignored in previous research. In experiment 1,native speakers of Mandarin produced statements, yes/no questions, particle ques-tions,wh-questions, rhetorical questions and confirmation questions with narrowfocus on the initial, medial or final word of the sentence, or on none of the words.Detailed F0 contour analyses showed that focus generated the same pitch rangemodification in questions as in statements, i.e., expanding the pitch range of thefocused word, suppressing (compressing and lowering) that of the post-focuswords, but leaving that of the pre-focus words largely unaffected. When the effects offocus (as well as other functions also potentially present) were controlled by sub-tractingstatement F0 contours from those of the corresponding yes/no questions,the resulting difference curves resembled exponential or even double-exponentialfunctions. Further F0 analyses also revealed an interaction between focus andinterrogative meaning in the form of a boost to the pitch raising by the question start-ingfrom the focused word. Finally, subtle differences in the amount of pitch raisingwere also observed among different types of questions, especially at the sentence-finalposition. Experiment 2 investigated whether listeners could detect both focusand question in the same utterance. Results showed that listeners could identifyboth in most cases, indicating that F0 variations related to the two functions could besimultaneously transmitted. Meanwhile, the lowest identification rates were foundfor neutral focus in questions and for statements with final focus. In both cases, theconfusions seemed to arise from the competing F0 adjustments by interrogativemeaning and focus at the sentence-final position. These findings are consistent withthe functional view of intonation, according to which components of intonation aredefined and organized by individual communicative functions that are independentof each other but are encoded in parallel.
Methodological Imperatives for Investigating the Phonetic Organization and Phonological Structures of Spontaneous Speech
Authors: Local J. , Walker G.
Published: February 2006

We describe and exemplify a methodology for providing an integratedaccount of the communicative function of parametric phonetic detail and its rela-tionshipwith interactional organization. We exemplify our analytic approach bydocumenting two different phonetic designs of stand-alone ‘so’ in a corpus ofrecorded American English telephone conversations. These two designs - whichencompass particular loudness, pitch and laryngeal characteristics - correlate withdifferent communicative functions and have different consequences for the inter-actional-sequential organization of the talk. We argue that if phonology is to betruly concerned with function and linguistic contrast, we need to induce thosefunctions and domains of contrast from a thoroughgoing phonetic and sequentialanalysis of talk-in-interaction.
Articulatory Planning Is Continuous and Sensitive to Informational Redundancy
Authors: Pluymaekers M. , Ernestus M. , Baayen R.
Published: February 2006

This study investigates the relationship between word repetition, predictabil-ityfrom neighbouring words, and articulatory reduction in Dutch. For the sevenmost frequent words ending in the adjectival suffix -lijk, 40 occurrences were ran-domlyselected from a large database of face-to-face conversations. Analysis ofthe selected tokens showed that the degree of articulatory reduction (as measuredby duration and number of realized segments) was affected by repetition, pre-dictabilityfrom the previous word and predictability from the following word.Interestingly, not all of these effects were significant across morphemes and tar-getwords. Repetition effects were limited to suffixes, while effects of predictabil-ityfrom the previous word were restricted to the stems of two of the seven targetwords. Predictability from the following word affected the stems of all targetwords equally, but not all suffixes. The implications of these findings for models ofspeech production are discussed.
The Communicative Functions of Final Rises in Finnish Intonation
Authors: Ogden R. , Routarinne S.
Published: February 2006

This paper considers the communicative function of final rises in Finnishconversational talk between pairs of teenage girls. Final rises are fairly common,occurring approximately twice a minute, predominantly on declaratives and in nar-rativesequences. We briefly consider the interplay between voice quality (known tobe a marker of transition relevance) and rising intonation in Finnish. We argue that innarrative sequences, rising terminals manage two main interactional tasks: they pro-videa place for a coparticipant to mark recipiency, and they project more talk by thecurrent speaker. Using a methodology which combines phonetic observation withconversation analysis, we demonstrate participants’ orientation to these functions.
Between Fall and Fall-Rise: Substance-Function Relations in German Phrase-Final Intonation Contours
Authors: Ambrazaitis G.
Published: February 2006

This study investigates an intonation contour of German whose status has notbeen established yet: a globally falling contour with a slight rise at the very end ofthe phrase (FSR). The contour may be said to lie on a phonetic continuum betweenfalling (F) and falling-rising (FR) contours. It is hypothesized that F, FR and FSR dif-ferwith respect to their communicative functions: F is terminal, FR is non-terminal,and FSR is pseudo-terminal, respectively. The hypotheses were tested in two steps.First, measurements in a labelled corpus of spontaneous speech provided the nec-essarybackground information on the phonetics of the contours. In the secondstep, the general hypothesis was approached in a perceptual experiment using theparadigm of a semantic differential: 49 listeners judged 17 systematically gener-atedstimuli on nine semantic scales, such as ‘impolite/polite’. The hypotheses weregenerally confirmed. Both F and FSR were associated with a conclusive statement,while FR was more likely to be judged as marking a question. FSR differs from F inthat it does not express features such as categoricalness, dominance or impolite-ness.The results are interpreted as an instance of the frequency code: the additionof a slight rise means avoidance of extremely low F0 ; the functional consequence isa reduction of communicated dominance.
Odor Identification and Decline in Different Cognitive Domains in Old Age
Authors: Wilson Robert S. , Arnold Steven E. , Tang Yuxiao , Bennett David A.
Published: February 2006

The authors examined the association of odor identification with rate of decline in different cognitive systems. Participants are 481 older persons from the Rush Memory and Aging Project. At baseline, the Brief Smell Identification Test was administered. At annual intervals for up to 3 years, a battery of 19 cognitive tests was administered from which previously established composite measures of 5 cognitive domains were derived. In mixed-effects models adjusted for age, sex, and education, lower odor identification score was associated with lower function at baseline in each cognitive domain. Lower score was also associated with more rapid decline in perceptual speed (estimate = 0.015, SE = 0.006, p = 0.013) and episodic memory (estimate = 0.012, SE = 0.006, p = 0.030) but not with rate of decline in semantic memory, working memory, or visuospatial ability. Thus, on average, a person with a low odor identification score (6, 10th percentile) declined more than twice as rapidly in perceptual speed and episodic memory as a person with a high score (11, 90th percentile). Results were unchanged in subsequent analyses that controlled for cigarette smoking or clinically diagnosed stroke. The results indicate that impaired odor identification in old age is associated with impaired global cognition and more rapid decline in perceptual processing speed and episodic memory.
Incidence of Dementia in Very Elderly Individuals: A Clinical, Neuropathological and Molecular Genetic Study
Authors: Polvikoski Tuomo , Sulkava Raimo , Rastas Sari , Sutela Annamaija , Niinistö Leena , Notkola Irma-Leena , Verkkoniemi Auli , Viramo Petteri , Juva Kati , Haltia Matti
Published: February 2006

Aims: To evaluate the effect of medical record use on figures for the incidence of dementia and the effect of apolipoprotein E (APOE) polymorphism on this incidence and neuropathologically defined Alzheimer’s disease (AD) in very elderly individuals. Methods: Cognitive functions were examined in a cohort of 328 (92% of the very elderly people of a town participated in this study) nondemented Finnish elderly individuals 85 years of age or more in 1991. The examination was repeated in survivors in 1994, 1996, 1999 and 2001. Medical notes and social work records were evaluated. All these individuals were genotyped for APOE. Neuropathological analysis of AD-type pathology was performed on 159 of 303 subjects who died during the follow-up. Results: Age group, gender or APOE did not significantly affect the incidence of dementia, which was over 20% higher (85 vs. 69 per 1,000 person-years) if the cognitive status at death was ascertained by medical and social work records than without this evaluation. The APOE υ4 allele was highly significantly (p = 0.002) and age almost significantly (p = 0.06) associated with neuropathological AD in nondemented individuals. Conclusions: Medical records should be analyzed in studies on the incidence of dementia in very elderly individuals. APOE polymorphism does not affect the incidence of dementia in this age group. However, clinical dementia diagnosis in very elderly individuals does not necessarily correlate well with the presence of neuropathological AD which, even in this age group, is significantly associated with the APOE υ4 allele.
The Relation of Education and Income to Cognitive Function among Professional Women
Authors: Lee Sunmin , Buring Julie E. , Cook Nancy R. , Grodstein Francine
Published: February 2006

We investigated the relation of educational attainment and annual household income to cognitive function and cognitive decline in community-dwelling women aged 66 years or older. Subjects were 6,314 health professionals participating in the Women’s Health Study, among whom information on education and income was self-reported. From 1998 to 2000, we administered five cognitive tests, measuring general cognition, episodic memory and verbal fluency, using a validated telephone interview. Second cognitive assessments were conducted approximately 2 years later; information was complete for 5,573 women at the time of analysis, with 94% follow-up. We used linear and logistic regression to calculate multivariate-adjusted mean differences as well as odds of cognitive impairment (defined as worst 10% of test distribution) and of substantial decline in performance (worst 10% of distribution), across various levels of education and income. After adjusting for numerous potential confounding factors, we found strong trends of increasing mean cognitive performance with increasing level of education (p trend < 0.0005 on all cognitive measures). Odds of cognitive impairment also consistently decreased with increasing education. For income, we found significant trends of increasing mean cognitive performance with increasing income on the summary score and on episodic memory (p trends < 0.0001). Results were generally similar for cognitive decline over 2 years, although slightly weaker. Thus, in these well-educated, professional women, educational attainment and income both predicted cognitive function and decline.
Exacerbation of Retinal Degeneration and Choroidal Neovascularization Induced by Subretinal Injection of Matrigel in CCL2/MCP-1-Deficient Mice
Authors: Shen Defen , Wen Rong , Tuo Jingsheng , Bojanowski Christine M. , Chan Chi-Chao
Published: February 2006

This study presents a mouse model for human age-related macular degeneration (AMD) as characterized by subretinal deposit and choroidal neovascularization. Matrigel, a basement membrane extract, solidifies after implantation in tissue and can stimulate local angiogenesis. This study demonstrates the induction of neovascularization and focal retinal degeneration following subretinal Matrigel injection in mice. In senescent mice, the normal functioning of CC chemokine CCL2/MCP-1 and its receptor CCR2 confers protection against age-related retinal degeneration, a disease that shares many similar features with human AMD. Our data shows that CCL2-deficient mice develop more severe disease as compared to the wild-type controls. These findings suggest that Matrigel subretinal injection could be used to generate AMD-like pathological changes. The data support the previously proposed role of CCL2 in AMD pathogenesis.
Inhibition of Lysosomal Degradation in Retinal Pigment Epithelium Cells Induces Exocytosis of Phagocytic Residual Material at the Basolateral Plasma Membrane
Authors: Peters Swaantje , Reinthal Eva , Blitgen-Heinecke Petra , Bartz-Schmidt Karl-Ulrich , Schraermeyer Ulrich
Published: February 2006

Purpose: To analyze chloroquine-induced morphological changes in the retinal pigment epithelium (RPE) and Bruch’s membrane (BM). Methods: Retina-choroid complexes of chloroquine-treated Long-Evans rats were analyzed by electron microscopy. Results: Intercellular spaces between the RPE cells and BM were enlarged. Residual material from phagosomes was released into these enlarged spaces. Debris accumulated within BM and encircled choriocapillaris endothelial cells. Conclusion: There is a release of undegraded phagocytic material (rod outer segments) into the extracellular space between BM and RPE cells, following inhibition of lysosomal degradation. Electron-dense deposits in BM and choriocapillaris may lead to reduced oxygen and nutrition flow.