bluuebunny/crossref_metadata_2025 huggingface dataset:
Genome‐wide profiling of stored mRNA inArabidopsis thalianaseed germination: epigenetic and genetic regulation of transcription in seed
Authors: Nakabayashi Kazumi , Okamoto Masanori , Koshiba Tomokazu , Kamiya Yuji , Nambara Eiji
Published: February 2005

To reveal the transcriptomes of Arabidopsis seed, comprehensive expression analysis was performed using ATH1 GeneChips (Affymetrix, Santa Clara, CA, USA). In the dry seed, more than 12 000 stored mRNA species were detected, including all ontological categories. Statistical analysis revealed that promoters of highly expressed genes in wild‐type dry seeds overrepresented abscisic acid‐responsive elements (ABREs) containing the core motif ACGT. Although the coupling element and seed‐specific enhancer RY motif alone were not prominently overrepresented in genes with high expression, the presence of these elements in combination with ABRE was associated with particularly high gene expression. The transcriptome of the imbibed seeds differed from that of the dry seed even at 6 h after seed imbibition. After imbibition many upregulated and downregulated genes were co‐regulated in clusters of three to five genes. Genes for which expression was affected by theabi5mutation tended to be located in clusters, suggesting that transactivation by ABI5 is not restricted to a single gene, but affects other proximal genes. Furthermore, cytosine methylation was observed not only in large silent retrotransposon clusters in centromeric regions, but also in non‐centromeric silent gene clusters in the seed. These results suggest that such regions might be transcriptionally silenced by methylation or heterochromatin structures. Our analyses reveal that transcriptomes of Arabidopsis seed are characterized by multiple regulatory mechanisms: epigenetic chromatin structures, chromosomal locations (e.g. co‐regulated gene clusters) andcis‐acting elements.
A Phytoalexin‐Like Flavonol Involved in the Carnation (Dianthus caryophyllus)‐Fusarium oxysporum f. sp. dianthi Pathosystem
Authors: Curir P. , Dolci M. , Galeotti F.
Published: February 2005

The fungitoxic flavonol triglycoside, kaempferide 3‐O‐[2G‐β‐d‐glucopyranosyl]‐β‐rutinoside, is a constituent of the carnation cultivar ‘Novada’, known as one of the most resistant cultivar to Fusarium oxysporum f. sp. dianthi, causative agent of Fusarium wilt. Due to its constitutive presence within the carnation tissues, this antifungal flavonol should be considered as a phytoanticipin; its biosynthesis, however, is stimulated by the inoculation with F. oxysporum f. sp. dianthi, just as is the rule for a typical phytoalexin. The results seem to indicate that in carnation the concentration of some preformed antifungal flavonoids may be significantly increased by a fungal presence: owing to their fungitoxic properties, these molecules could cooperate, together with the unconstitutive and postinfectional anthranilic acid‐derivative phytoalexins, to the plant defensive response against Fusarium attacks.
Genetic Structure of Pyricularia grisea (Cooke) Sacc. Isolates from Italian Paddy Fields
Authors: Piotti E. , Rigano M. M. , Rodino D. , Rodolfi M. , Castiglione S. , Picco A. M. , Sala F.
Published: February 2005

Rice blast disease, caused by the fungus Pyricularia grisea (Cooke) Sacc., is responsible for considerable damages in rice crops in Italy and in other parts of the world. This study was conducted in order to investigate the genetic structure of a P. grisea population in the Po area, the largest rice area in Italy. Rice leaves showing blast symptoms were collected in three successive years (1998–2000) and 43 P. grisea monoconidial culture samples were isolated from infected rice leaves. Fungal DNAs were obtained from mycelia. Moreover, six additional P. grisea DNA samples representative for the five characterized European lineages were also investigated. All 49 DNAs were fingerprinted using the Pot2‐based repetitive polymerase chain reaction specific for the blast pathogen. Unweighted pair‐group method with arithmetic averages cluster analysis shows the presence of three main Italian lineages. Within lineages, similarity was higher than 80%. Samples representative of the three of five known European lineages grouped within these three Italian lineages confirming the presence of three European lineages in Italy. Furthermore, cluster analysis shows the presence of two new haplotypes never found before in the Italian lineage.
Characterization of Alder Phytophthora Isolates from Wallonia and Development of SCAR Primers for their Specific Detection
Authors: De Merlier D. , Chandelier A. , Debruxelles N. , Noldus M. , Laurent F. , Dufays E. , Claessens H. , Cavelier M.
Published: February 2005

Isolates of alder Phytophthora were collected in the southern part of Belgium on riverbanks planted with Alnus glutinosa and A. incana. They were compared with strains isolated in other European countries in terms of maximum temperature for growth, oogonia shape, pathogenicity on Alnus seedlings and genetic traits. Using both molecular techniques [random amplified polymorphic DNA (RAPD) and random amplified microsatellite (RAMS)], two groups of isolates were identified, the first group being further divided into two subgroups, Ia and Ib, using RAPD. Most of the Walloon alder Phytophthora isolates as well as the standard type from UK (formally designated P. alni subsp. alni) fell into group Ia. One isolate was classified in group Ib with the German and Dutch variants (P. alni subsp. multiformis), while three isolates were placed with the Swedish variant (P. alni subsp. uniformis) in group II. In terms of morphological properties, isolates from groups Ia and Ib developed colonies with a felt‐like appearance and usually produced numerous oogonia, varying from wavy to warty after 1 week (group Ia) or 2–3 weeks (Ib) in darkness. In contrast, colonies from group II isolates were generally irregular, and smooth oogonia were produced in low quantities after approximately 1 month in culture. A polymerase chain reaction (PCR) using sequence‐characterized amplification region (SCAR) primers derived from a polymorphic amplification product generated with a RAPD primer was developed for the specific detection of alder Phytophthora. The specificity and sensitivity of this test are discussed here.
Collective action and subordinate group identity in a simulated society game
Authors: HIROSE YUKIO , TARESAWA YUMIKO , OKUDA TATSUYA
Published: February 2005

Abstract:  This research examined the effects of upward mobility and resource disparity on subordinates’ collective action and group identity in a context of intergroup negotiation by using a simulated society (SIMSOC) game. According to the social identity theory, it was hypothesized that when individual mobility opportunities for a subordinate group increase, the members of the subordinate group are less likely to participate in collective actions and to appreciate the merits of their own group identity. Four hundred and fifty‐four undergraduates participated in 12 separate SIMSOC games. For each game, approximately 40 undergraduates were divided into dominant and subordinate groups. Each of the four combinations of high/low levels of upward mobility and large/small resource disparity was played out three times. Subordinates in the low‐mobility condition acted collectively more frequently and evaluated their own group more positively than those in the high‐mobility condition. A signifificant positive correlation between the frequency of subordinates’ collective action and in‐group favoritism was found.
The History of Political Science
Authors: Adcock Robert , Bevir Mark
Published: February 2005

The history of political science serves as a context within which we make sense of the nature and role of our discipline. Narratives about the past development of British and American political science help to frame debates, choices, and identities within the contemporary discipline in Britain. What do recent studies on the history of political science tell us about the character of political science in Britain and America? What do they suggest about the relation of the British study of politics to British identities more generally? Our review of recent work concentrates on three issues: (1) how historical studies of political science relate to approaches and identities within the contemporary discipline; (2) how they relate to the past, i.e. whether their historical vision is marred by presentism; (3) whether they look beyond the boundaries of the discipline.
Concepts of Fascism in Contemporary Russia and the West
Authors: Umland Andreas
Published: February 2005

During the 1990s, Western comparative fascist studies underwent a process of consolidation. A growing number of scholars agreed to and now use various forms of a more or less consensual definition of fascism as an extremely nationalistic and revolutionary ideology. In contrast, the conceptualisations and applications of ‘fascism’ in post-Soviet Russia are contradictory continuing Soviet misuse of the term. Increasing anti-democratic tendencies in Russian politics and society suggest closer attention by Western scholars to putative post-Soviet fascisms.
Infraciliature and Morphogenesis in Three Rumen Diplodinium Ciliates, Diplodinium polygonale, Diplodinium leche, and Diplodinium nanum, Observed by Light Microscopy
Authors: Ito Akira , Imai Soichi
Published: February 2005

Abstract. Infraciliature and morphogenesis of three rumen ophryoscolecid ciliates, Diplodinium polygonale Dogiel, 1925, Diplodinium leche Imai et al., 1992, and Diplodinium nanum Imai, 1988, are described from pyridinated silver carbonate‐impregnated specimens. These three species have two polybrachykineties in the buccal area and a polybrachykinety in the dorsal ciliary zone. The vestibular polybrachykinety (VP) of D. polygonale and D. leche arises from the dorsal extremity of the adoral polybrachykinety (AP) as in Entodinium species, extending toward the left in D. polygonale and toward the left posterior in D. leche. The VP of D. nanum arises from the inner side of the AP, separate from its dorsal extremity, as in other Diplodinium species and extends toward the left posterior. These series of the polybrachykinety arrangements in D. polygonale, D. leche, and D. nanum can be regarded as transitional forms in the evolution of an Entodinium‐like ancestor to Diplodinium. Morphogenesis of these three Diplodinium species is not different from that of other Diplodinium species.
Age and perception of dental appearance and tooth colour
Authors: Alkhatib Mhd N. , Holt Ruth , Bedi Raman
Published: February 2005

Objectives:  To determine the prevalence of satisfaction with dental appearance and own tooth colour in the UK and investigate the impact of ageing on these perceptions.

Methods:  Data about ageing and satisfaction with dental appearance and tooth colour was gathered by means of a questionnaire completed at face‐to‐face interview. The questionnaire was first tested and then used by the Office of National Statistics (ONS) in a stratified random sample of adults drawn from the UK. A total of 3384 adults were interviewed.

Results:  Three quarters of the population were satisfied with their own dental appearance and two‐thirds were satisfied with their tooth colour. Subjects over the age of 55 were significantly more likely to be satisfied with their dental appearance and tooth colour (p < 0.05) compared with younger age groups.

Conclusions:  Ageing is not necessarily associated with negative self‐perception of dental appearance or tooth colour. Greater dissatisfaction with dental appearance or colour in younger ages may suggest that perceived appearance is linked to cognitive factors other than social or cultural ones.
Mispolarization of desmosomal proteins and altered intercellular adhesion in autosomal dominant polycystic kidney disease
Authors: Silberberg Melina , Charron Audra J. , Bacallao Robert , Wandinger-Ness Angela
Published: February 2005

Polycystin-1, the product of the major gene mutated in autosomal dominant polycystic kidney disease (ADPKD), has been shown to associate with multiple epithelial cell junctions. Our hypothesis is that polycystin-1 is an important protein for the initial establishment of cell-cell junctions and maturation of the cell and that polycystin-1 localization is dependent on the degree of cell polarization. Using laser-scanning confocal microscopy and two models of cell polarization, polycystin-1 and desmosomes were found to colocalize during the initial establishment of cell-cell contact when junctions were forming. However, colocalization was lost in confluent monolayers. Parallel morphological and biochemical evaluations revealed a profound mispolarization of desmosomal components to both the apical and basolateral domains in primary ADPKD cells and tissue. Studies of the intermediate filament network associated with desmosomes showed that there is a decrease in cytokeratin levels and an abnormal expression of the mesenchymal protein vimentin in the disease. Moreover, we show for the first time that the structural alterations seen in adherens and desmosomal junctions have a functional impact, leaving the ADPKD cells with weakened cell-cell adhesion. In conclusion, in this paper we show that polycystin-1 transiently colocalizes with desmosomes and that desmosomal proteins are mislocalized as a consequence of polycystin-1 mutation.
EGF stimulates mesangial cell mitogenesis via PI3-kinase-mediated MAPK-dependent and AKT kinase-independent manner: involvement of c-fosand p27Kip1
Authors: Mahimainathan Lenin , Ghosh-Choudhury Nandini , Venkatesan Balachandar A. , Danda Ratna S. , Choudhury Goutam Ghosh
Published: February 2005

Epidermal growth factor (EGF) is a potent mitogen for mesangial cells. The mechanism by which EGF induces DNA synthesis is not precisely understood. We investigated the role of phosphatidylinositol (PI)3-kinase in regulating mitogenesis. EGF increased PI3-kinase activity resulting in stimulation of PDK-1 and Akt kinase activities. Blocking of PI3-kinase activity using LY-294002 or adenoviral expression of PTEN, which dephosphorylates PI3,4,5-tris-phosphate and thus inactivates PI3-kinase signaling, significantly inhibits EGF-induced DNA synthesis. Expression of dominant-negative Akt kinase, however, had no effect on DNA synthesis. But it inhibited EGF-induced phosphorylation of FoxO3a transcription factor, thus demonstrating its functional consequences. These data indicate that EGF increases the DNA synthesis in a PI3-kinase-dependent but Akt-independent manner. In addition to activating PI3-kinase signaling, EGF increased Erk1/2 MAPK activity, leading to transcriptional activation of its nuclear target Elk-1 and resulting in c- fos expression. Inhibition of MAPK activity by MEK inhibitor U-0126 abolished EGF-induced DNA synthesis. Because EGF activates PI3-kinase, which also regulates DNA synthesis, the effect of PI3-kinase on MAPK activity was also examined. Inhibition of PI3-kinase signaling blocked EGF-induced MAPK activity as well as Elk-1-dependent reporter transcription and c- fos gene transcription. To further determine the mechanism of EGF-induced DNA synthesis, we investigated the effect of EGF on the cyclin-dependent kinase inhibitor p27Kip1. EGF reduced the expression of p27Kip1. Inhibition of PI3-kinase action or MAPK activity abolished the reduction in p27Kip1expression induced by EGF. These data provide the evidence that a linear signal transduction pathway involving PI3-kinase-dependent MAPK regulates EGF-induced DNA synthesis in mesangial cells by regulating c- fos and p27Kip1expression.
Physiological aspects of high-altitude pulmonary edema
Authors: Bärtsch Peter , Mairbäurl Heimo , Maggiorini Marco , Swenson Erik R.
Published: February 2005

High-altitude pulmonary edema (HAPE) develops in rapidly ascending nonacclimatized healthy individuals at altitudes above 3,000 m. An excessive rise in pulmonary artery pressure (PAP) preceding edema formation is the crucial pathophysiological factor because drugs that lower PAP prevent HAPE. Measurements of nitric oxide (NO) in exhaled air, of nitrites and nitrates in bronchoalveolar lavage (BAL) fluid, and forearm NO-dependent endothelial function all point to a reduced NO availability in hypoxia as a major cause of the excessive hypoxic PAP rise in HAPE-susceptible individuals. Studies using right heart catheterization or BAL in incipient HAPE have demonstrated that edema is caused by an increased microvascular hydrostatic pressure in the presence of normal left atrial pressure, resulting in leakage of large-molecular-weight proteins and erythrocytes across the alveolarcapillary barrier in the absence of any evidence of inflammation. These studies confirm in humans that high capillary pressure induces a high-permeability-type lung edema in the absence of inflammation, a concept first introduced under the term “stress failure.” Recent studies using microspheres in swine and magnetic resonance imaging in humans strongly support the concept and primacy of nonuniform hypoxic arteriolar vasoconstriction to explain how hypoxic pulmonary vasoconstriction occurring predominantly at the arteriolar level can cause leakage. This compelling but as yet unproven mechanism predicts that edema occurs in areas of high blood flow due to lesser vasoconstriction. The combination of high flow at higher pressure results in pressures, which exceed the structural and dynamic capacity of the alveolar capillary barrier to maintain normal alveolar fluid balance.
Transcriptional response of bronchial epithelial cells to Pseudomonas aeruginosa: identification of early mediators of host defense
Authors: Vos Joost B. , van Sterkenburg Marianne A. , Rabe Klaus F. , Schalkwijk Joost , Hiemstra Pieter S. , Datson Nicole A.
Published: February 2005

The airway epithelium responds to microbial exposure by altering expression of a variety of genes to increase innate host defense. We aimed to delineate the early transcriptional response in human primary bronchial epithelial cells exposed for 6 h to a mixture of IL-1β and TNF-α or heat-inactivated Pseudomonas aeruginosa. Because molecular mechanisms of epithelial innate host defense are not fully understood, the open-ended expression-profiling technique SAGE was applied to construct gene expression profiles covering 30,000 genes: 292 genes were found to be differentially expressed. Expression of seven genes was confirmed by real-time qPCR. Among differentially expressed genes, four classes or families were identified: keratins, proteinase inhibitors, S100 calcium-binding proteins, and IL-1 family members. Marked transcriptional changes were observed for keratins that form a key component of the cytoskeleton in epithelial cells. Expression of antimicrobial proteinase inhibitors SLPI and elafin was elevated after microbial or cytokine exposure. Interestingly, expression of numerous S100 family members was observed, and eight members, including S100A8 and S100A9, were among the most differentially expressed genes. Differential expression was also observed for the IL-1 family members IL-1β, IL-1 receptor antagonist, and IL-1F9, a newly discovered IL-1 family member. Clustering of differentially expressed genes into biological processes revealed that the early inflammatory response in airway epithelial cells to IL-1β-TNF-α and P. aeruginosa is characterized by expression of genes involved in epithelial barrier formation and host defense.
Reflecting upon Feelings: An fMRI Study of Neural Systems Supporting the Attribution of Emotion to Self and Other
Authors: Ochsner Kevin N. , Knierim Kyle , Ludlow David H. , Hanelin Josh , Ramachandran Tara , Glover Gary , Mackey Sean C.
Published: February 2005

Understanding one's own and other individual's emotional states is essential for maintaining emotional equilibrium and strong social bonds. Although the neural substrates supporting reflection upon one's own feelings have been investigated, no studies have directly examined attributions about the internal emotional states of others to determine whether common or distinct neural systems support these abilities. The present study sought to directly compare brain regions involved in judging one's own, as compared to another individual's, emotional state. Thirteen participants viewed mixed valence blocks of photos drawn from the International Affective Picture System while whole-brain fMRI data were collected. Preblock cues instructed participants to evaluate either their emotional response to each photo, the emotional state of the central figure in each photo, or (in a baseline condition) whether the photo was taken indoors or outdoors. Contrasts indicated (1) that both self and other judgments activated the medial prefrontal cortex (MPFC), the superior temporal gyrus, and the posterior cingulate/precuneus, (2) that self judgments selectively activated subregions of the MPFC and the left temporal cortex, whereas (3) other judgments selectively activated the left lateral prefrontal cortex (including Broca's area) and the medial occipital cortex. These results suggest (1) that self and other evaluation of emotion rely on a network of common mechanisms centered on the MPFC, which has been hypothesized to support mental state attributions in general, and (2) that medial and lateral PFC regions selectively recruited by self or other judgments may be involved in attention to, and elaboration of, internally as opposed to externally generated information.
Contextual Modulation of Amygdala Responsivity to Surprised Faces
Authors: Kim Hackjin , Somerville Leah H. , Johnstone Tom , Polis Sara , Alexander Andrew L. , Shin Lisa M. , Whalen Paul J.
Published: February 2005

We recently demonstrated a functional relationship between fMRI responses within the amygdala and the medial prefrontal cortex based upon whether subjects interpreted surprised facial expressions positively or negatively. In the present fMRI study, we sought to assess amygdala–medial prefrontal cortex responsivity when the interpretations of surprised faces were determined by contextual experimental stimuli, rather than subjective judgment. Subjects passively viewed individual presentations of surprised faces preceded by either a negatively or positively valenced contextual sentence (e.g., She just found $500 vs. She just lost $500). Negative and positive sentences were carefully matched in terms of length, situations described, and arousal level. Negatively cued surprised faces produced greater ventral amygdala activation compared to positively cued surprised faces. Responses to negative versus positive sentences were greater within the ventrolateral prefrontal cortex, whereas responses to positive versus negative sentences were greater within the ventromedial prefrontal cortex. The present study demonstrates that amygdala response to surprised facial expressions can be modulated by negatively versus positively valenced verbal contextual information. Connectivity analyses identified candidate cortical–subcortical systems subserving this modulation.
Grasping the Intentions of Others: The Perceived Intentionality of an Action Influences Activity in the Superior Temporal Sulcus during Social Perception
Authors: Pelphrey Kevin A. , Morris James P. , McCarthy Gregory
Published: February 2005

An explication of the neural substrates for social perception is an important component in the emerging field of social cognitive neuroscience and is relevant to the field of cognitive neuroscience as a whole. Prior studies from our laboratory have demonstrated that passive viewing of biological motion (Pelphrey, Mitchell, et al., 2003; Puce et al., 1998) activates the posterior superior temporal sulcus (STS) region. Furthermore, recent evidence has shown that the perceived context of observed gaze shifts (Pelphrey, Singerman, et al., 2003; Pelphrey et al., 2004) modulates STS activity. Here, using event-related functional magnetic resonance imaging at 4 T, we investigated brain activity in response to passive viewing of goal- and non-goal- directed reaching-to-grasp movements. Participants viewed an animated character making reaching-to-grasp movements either toward (correct) or away (incorrect) from a blinking dial. Both conditions evoked significant posterior STS activity that was strongly right lateralized. By examining the time course of the blood oxygenation level-dependent response from areas of activation, we observed a functional dissociation. Incorrect trials evoked significantly greater activity in the STS than did correct trials, while an area posterior and inferior to the STS (likely corresponding to the MT/V5 complex) responded equally to correct and incorrect movements. Parietal cortical regions, including the superior parietal lobule and the anterior intraparietal sulcus, also responded equally to correct and incorrect movements, but showed evidence for differential responding based on the hand and arm (left or right) of the animated character used to make the reaching-to-grasp movement. The results of this study further suggest that a region of the right posterior STS is involved in analyzing the intentions of other people's actions and that activity in this region is sensitive to the context of observed biological motions.
Implicit and Explicit Evaluation: fMRI Correlates of Valence, Emotional Intensity, and Control in the Processing of Attitudes
Authors: Cunningham William A. , Raye Carol L. , Johnson Marcia K.
Published: February 2005

Previous work suggests that explicit and implicit evaluations (good–bad) involve somewhat different neural circuits that process different dimensions such as valence, emotional intensity, and complexity. To better understand these differences, we used functional magnetic resonance imaging to identify brain regions that respond differentially to such dimensions depending on whether or not an explicit evaluation is required. Participants made either good–bad judgments (evaluative) or abstract–concrete judgments (not explicitly evaluative) about socially relevant concepts (e.g., “murder,” “happiness,” “abortion,” “welfare”). After scanning, participants rated the concepts for goodness, badness, emotional intensity, and how much they tried to control their evaluation of the concept. Amygdala activation correlated with emotional intensity and right insula activation correlated with valence in both tasks, indicating that these aspects of stimuli were processed by these areas regardless of intention. In contrast, for the explicitly evaluative good–bad task only, activity in the anterior cingulate, frontal pole, and lateral areas of the orbital frontal cortex correlated with ratings of control, which in turn were correlated with a measure of ambivalence. These results highlight that evaluations are the consequence of complex circuits that vary depending on task demands.
A Barotropic Envelope Rossby Soliton Model for Block–Eddy Interaction. Part II: Role of Westward-Traveling Planetary Waves
Authors: Luo Dehai
Published: February 2005

The role of westward-traveling planetary waves in the block onset and the deformation of eddies during the interaction between synoptic-scale eddies and an incipient block is first examined by constructing an incipient block that consists of a stationary dipole wave for zonal wavenumber 2 and a westward-traveling monopole wave with constant amplitude (C wave) for zonal wavenumber 1 or 2. It is shown that the C-wave can affect the onset and strength of blocking through influencing the preblock (diffluent) flow even though it does not affect the amplification of the dipole wave associated with the synoptic-scale eddies. Whether the storm tracks organized by the deformed eddies deflect northward depends upon the zonal wavenumber, amplitude, and phase of the C wave relative to the stationary dipole wave. A typical retrograde blocking anticyclone can arise through the interaction of an incipient block with synoptic-scale perturbations when the C-wave ridge with zonal wavenumber 1 shifts westward from the east of the dipole wave in an incipient block. In this process, a slight northward deflection of organized storm tracks is also observed, particularly under the condition of a large-amplitude C wave.

In addition, the interaction between a diffluent flow, consisting of a coupled dipole and monopole waves, and upstream synoptic-scale eddies is investigated. It is found that the eddy forcing tends to not only periodically amplify the dipole soliton and to retard its eastward movement, but to make the monopole wave break up. The breaking of the traveling monopole wave will suppress the eddy-induced blocking ridge that exhibits a surf zone structure where the negative meridional gradient of planetary-scale potential vorticity exists and cause the planetary-scale blocking field to lose its closed circulation compared to that without coupling.
Assessment of Hydrometeor Collection Rates from Exact and Approximate Equations. Part I: A New Approximate Scheme
Authors: Gaudet Brian J. , Schmidt Jerome M.
Published: February 2005

The collection equation is analyzed for the case of two spherical hydrometeors with collection efficiency unity and exponential size distributions. When the fall velocities are significantly different a more general form of the conventional Wisner approximation can be formulated. The accuracy of the new formula exceeds that of the Wisner approximation for all cases considered, except for the collection of a faster species by a slower species if the amount of the faster species is relatively small compared with that of the slower species. The exact solution of the collection equation is then rederived and cast into the form of a power series involving the ratio of the two characteristic fall velocities. It is shown that the new formulation is a first-order correction to the continuous collection equation for hydrometeors with finite diameters and fall velocities. Based on the analysis, the implications for the behavior of both the exact collection equation and its representation in numerical models are discussed.
Spatial and Temporal Variations of Gravity Wave Parameters. Part I: Intrinsic Frequency, Wavelength, and Vertical Propagation Direction
Authors: Wang Ling , Geller Marvin A. , Alexander M. Joan
Published: February 2005

Five years (1998–2002) of U.S. high vertical resolution radiosonde data are analyzed to derive important gravity wave parameters, such as intrinsic frequencies, vertical and horizontal wavelengths, and vertical propagation directions in the lower stratosphere and troposphere.

Intrinsic frequencies ω̂ increase with increasing latitude, with larger values in the troposphere. In the lower stratosphere, ω̂ is higher in winter than in summer, especially at mid- and high latitudes. Intrinsic frequencies divided by the Coriolis parameter f are ∼4 in the troposphere, and ∼2.4–3 in the lower stratosphere. The lower-stratospheric ω̂/f generally decreases weakly with increasing latitude. The latitudinal distributions of the lower-stratospheric ω̂/f are explained largely by the propagation effects. The seasonal variations of ω̂ in the lower stratosphere are found to be related to the variations of the background wind speeds.

Dominant vertical wavelengths decrease with increasing latitude in the lower stratosphere, and maximize at midlatitudes (35°–40°N) in the troposphere. They are generally longer in winter than in summer. The variations of the dominant vertical wavelengths are found to be associated with the similar variations in gravity wave energies. Dominant horizontal wavelengths decrease with increasing latitude, with larger values in the lower stratosphere.

Approximately 50% of the tropospheric gravity waves show upward energy propagation, whereas there is about 75% upward energy propagation in the lower stratosphere. The lower-stratospheric fraction of upward energy propagation is generally smaller in winter than in summer, especially at mid- and high latitudes. The seasonal variation of upward fraction is likely an artifice due to the analysis method, although a small part of it may be interpreted by the variations in background wind speeds.

Results suggest that propagation effects are much more important than source variations for explaining the large-scale time-average properties of waves observed by radiosondes.
Ascending Multiple‐Dose Pharmacokinetics of Viramidine, a Prodrug of Ribavirin, in Adult Subjects With Compensated Hepatitis C Infection
Authors: Aora Sanjee , Xu Christine , Teng Alice , Peterson Janet , Yeh Li‐Tain , Gish Robert , Lau Daryl , Rossi Stephen , Lin Chin‐chung
Published: February 2005

The current study was carried out to evaluate pharmacokinetic profiles of viramidine and ribavirin in patients (n = 8 per dose group) with compensated hepatitis C infection following oral dosing of viramidine (400, 600, or 800 mg bid for 4 weeks). Pharmacokinetic parameters were determined on days 1 and 29 based on plasma, red blood cell, and urine concentrations of viramidine and ribavirin. The results indicate rapid absorption and conversion of viramidine to ribavirin after oral administration of viramidine. Viramidine and ribavirin exposure in plasma and RBCs generally increased from the 400‐ to 600‐mg dose level of viramidine. However, no further increase in exposure was noted at the 800‐mg dose. Long half‐lives for viramidine (66–76 hours in plasma and 200–420 hours in red blood cells) and ribavirin (340–410 hours in plasma and 360–430 hours in red blood cells) were noted. A negligible amount of viramidine (1%–4% of dose) and a small amount of ribavirin (9%–14% of dose) were excreted in the urine. The renal clearance was low for both viramidine (5–8 L/h) and ribavirin (4–7 L/h). Significant accumulation of viramidine was noted in red blood cells (accumulation factor [R] = 5–8) but not in plasma (R = 2). Extensive accumulation of ribavirin was noted in both plasma (R = 9–17) and red blood cells (R = 77–129). Steady‐state levels of ribavirin and viramidine in plasma and red blood cells were achieved by day 22. At steady state, there was extensive conversion of viramidine to ribavirin in both plasma and red blood cells. Both viramidine and ribavirin were preferentially distributed into red blood cells than plasma.
Population Pharmacokinetic Analysis and Simulation of the Time‐Concentration Profile of Etanercept in Pediatric Patients With Juvenile Rheumatoid Arthritis
Authors: Yim Dong‐Seok , Zhou Honghui , Buckwalter Mary , Nestorov Ivan , Peck Carl C. , Lee Howard
Published: February 2005

This study was performed to estimate the population pharmacokinetic (PK) parameters of etanercept in pediatric juvenile rheumatoid arthritis (JRA) patients and to compare the steady‐state time‐concentration profiles between etanercept 0.8‐mg/kg once‐weekly and 0.4‐mg/kg twice‐weekly subcutaneous (SC) regimens by clinical trial simulation. To this end, mixed‐effect analysis (NONMEM, Version 5.1) was performed using the etanercept PK database consisting of 69 JRA patients (4–17 years). Based on the population PK parameters obtained herein, a Monte Carlo clinical trial simulation experiment was conducted to compare the PK profiles in 200 virtual JRA patients who randomly received either etanercept 0.4 mg/kg SC twice weekly or 0.8 mg/kg once weekly for 12 weeks. The following population PK model could adequately describe etanercept PK profiles for twice‐weekly SC dosing of 0.4 mg/kg:

image

The means ± standard deviations of simulated trough concentrations for 0.8‐mg/kg once‐weekly and 0.4‐mg/kg twice‐weekly dosing regimens were 1.58 ± 1.07 mg/L and 1.92 ± 1.09 mg/L, respectively. Peaks during 0.8‐mg/kg once‐weekly dosing (2.92 ± 1.41 mg/L) were only 11% higher than during 0.4 mg/kg twice‐weekly dosing (2.62 ± 1.23 mg/L). In conclusion, the clinical trial simulation confirmed that 0.8‐mg/kg once‐weekly and 0.4‐mg/kg twice‐weekly SC regimens of etanercept are expected to yield overlapping steady‐state time‐concentration profiles, leading to equivalent clinical outcomes. This has been the basis of the recent Food and Drug Administration approval of the 0.8‐mg/kg once‐weekly regimen in pediatric patients with JRA.
Effect of Multiple‐Dose Dexloxiglumide on the Pharmacokinetics of Oral Contraceptives in Healthy Women
Authors: Roy Partha , Jakate Abhijeet S. , Patel Alpita , Abramowitz Wattanaporn , Wangsa Julie , Persiani Stefano , Kapil Ram
Published: February 2005

This study was undertaken to evaluate the effect of dexloxiglumide, a selective cholecystokinin receptor antagonist, on the pharmacokinetics of a combination oral contraceptive (OC). A single‐blind, placebo‐controlled, 2‐period crossover study was conducted in 24 healthy young female subjects who received Ortho Tri‐Cyclen containing ethinyl estradiol (EE, 0.035 mg) and norgestimate (NE, 0.180 mg/ 0.215 mg/0.250 mg per 7‐day phase, respectively) for 5 days (days 17–21) concurrently with either 200 mg dexloxiglumide (3 times a day on days 17–20, followed by a single dose on day 21) or matching placebo during 2 consecutive 28‐day OC dosing cycles. Plasma was sampled up to 24 hours for the determination of EE, NE, and 17‐deactyl norgestimate (17‐DNE, a rapidly formed pharmacologically active metabolite of NE). The geometric mean ratios (GMRs, dexloxiglumide/placebo) of the plasma concentration‐time curve over 24 hours with corresponding 90% confidence intervals (CIs) for EE and 17‐DNE were 1.21 (1.17–1.26) and 0.92 (0.89–0.95), respectively. The GMRs (90% CI) of Cmax for EE and 17‐DNE were 1.15 (1.09–1.20) and 0.93 (0.90–0.96), respectively. Coadministration of OC and dexloxiglumide was well tolerated and safe. Comparable systemic exposure of EE and 17‐DNE in the presence and absence of dexloxiglumide suggests that dexloxiglumide treatment is unlikely to interfere with the safety and efficacy of oral contraceptives based on the analysis of the resulting pharmacokinetic profile.
Topical Ketoprofen Patch (100 mg) for the Treatment of Ankle Sprain: A Randomized, Double-Blind, Placebo-Controlled Study
Authors: Mazières Bernard , Rouanet Stéphanie , Velicy Joanne , Scarsi Claudia , Reiner Valentina
Published: February 2005

Background

Topical nonsteroidal anti-inflammatory drugs offer the advantage of enhanced drug delivery to local affected tissues with low plasma levels and an expected reduced incidence of systemic adverse events (mainly peptic ulcer disease and gastrointestinal hemorrhage).

Hypothesis

To test the efficacy and tolerability of a 100-mg patch of ketoprofen applied once a day.

Study Design

Randomized controlled clinical trial; Level of evidence, 1.

Methods

The 2-week trial included patients suffering painful (spontaneous pain ≥50 mm on a 0- to 100-mm visual analog scale), benign (grade I or II), recent (<2 days) ankle sprains as a model of general traumatic soft tissue injuries. The primary efficacy criterion was spontaneous pain change after 7 days of treatment in the intention-to-treat population. One hundred sixty-three patients were randomized (ketoprofen, 81; placebo, 82).

Results

After 1 week of treatment, the decrease in spontaneous pain was -50 ± 20 mm for ketoprofen and -38 ± 24 mm for the placebo, showing a statistically significant intergroup difference (P =. 0007). The majority of the secondary criteria were also statistically significant in favor of the ketoprofen patch. Tolerance was good in both groups, adverse events being mostly local.

Conclusion

This trial suggested that a 7-day course of treatment with a ketoprofen patch is useful in benign ankle sprain, without revealing unexpected adverse events.
Risk Factors for Injury in Subelite Rugby League Players
Authors: Gabbett Tim J. , Domrow Nathan
Published: February 2005

Background

Although player fatigue and playing intensity have been suggested to contribute to injuries in rugby league players, no study has confirmed if the level of physical fitness is a risk factor for injury in rugby league players. The aim of this study was to identify risk factors for injury in subelite rugby league players.

Hypothesis

Low physical fitness levels are risk factors for injury in subelite rugby league players.

Study Design

Cohort study; Level of evidence, 2.

Methods

One hundred fifty-three players from a subelite rugby league club underwent preseason measurements of muscular power (vertical jump), speed (10- and 40-m sprint), and maximal aerobic power (multistage fitness test) over 4 competitive seasons. All injuries sustained by players were prospectively recorded over the 4 competitive seasons.

Results

The risk of injury was greater in players with low 10- and 40-m speed. Players with a low maximal aerobic power had a greater risk of sustaining a contact injury. In addition, players who completed less than 18 weeks of training before sustaining their initial injuries were at greater risk of sustaining a subsequent injury.

Conclusions

Subelite rugby league players with low speed and maximal aerobic power are at an increased risk of injury. In addition, players who complete less than 18 weeks of training before sustaining an initial injury are at greater risk of sustaining a subsequent injury. These findings highlight the importance of speed and endurance training to reduce the incidence of injury in subelite rugby league players.
Reliability of Stress Radiography for Evaluation of Posterior Knee Laxity
Authors: Schulz Martin S. , Russe Kai , Lampakis Georgios , Strobel Michael J.
Published: February 2005

Background

Although stress radiography has been recommended for quantifying posterior tibial displacement in knees with posterior cruciate ligament insufficiency, the intratester reliability and intertester reliability of this measurement method have not been evaluated.

Hypothesis

Stress radiography is a reproducible measurement method in the assessment of posterior knee laxity in patients with posterior cruciate ligament lesions.

Study Design

Cohort study (diagnosis); Level of evidence, 2.

Methods

Stress radiographs of 787 patients with suspected posterior cruciate ligament lesions taken using the Telos device were evaluated independently by 3 testers: 2 of the testers were clinically experienced in the evaluation of stress radiographs, and 1 tester was a novice tester. Change in mean, standard error of measurement with calculated confidence intervals, and intraclass correlation coefficients were determined to assess intratester and intertester reliability.

Results

There was no significant intratester change in mean. Intratester standard error of measurement was 1.03 mm; 95% confidence intervals were ±2.02 mm for a single measurement and ±2.86 mm for a change in measurement. The intratester intraclass correlation coefficient was 0.95. Intertester reliability revealed a significant change in mean between the experienced testers and the novice tester (P <. 001). There was no substantial difference for the standard error of measurement of each tester. The mean intertester standard error of measurement was 1.41 mm; 95% confidence intervals were ±2.77 mm for a single measurement and ±3.91 mm for a change in measurement. The intertester intraclass correlation coefficient was 0.91.

Conclusion

Stress radiography was found to be a measurement method with a useful reliability for evaluation of posterior laxity in patients with posterior cruciate ligament lesions. The reproducibility of stress radiography may be influenced by multiple variables, and standardized methods are needed to minimize measurement error.
Predicting in vivo Clinical Performance of Anterior Cruciate Ligament Fixation Methods from in Vitro Analysis
Authors: Saweeres Emad S. B. , Kuiper Jan H. , Evans Richard O. , Richardson James B. , White Stephen H.
Published: February 2005

Background

Anterior cruciate ligament graft fixations experience cyclic loads in vivo. Present cyclic loading studies testing fixation use “incremental cycling,”“residual strength” protocols, or a combination. Industrial standards, however, rely on fatigue life testing and use tolerance limits to determine guaranteed minimum levels of cycles to failure.

Hypothesis

Industrial standards of fatigue life and lower tolerance limits provide a more conservative assessment of cycles to failure than do currently used cyclic loading models, and they facilitate interpretation of data toward clinical performance.

Study Design

Descriptive laboratory study.

Methods

Fatigue life curves and lower tolerance limits were calculated for porcine patellar tendon graft fixations that were tested to failure in single pulls or cycled to failure at 2 different load levels. A log curve was constructed so that the expected values at other load levels could be calculated. Comparison of a metal and a composite resorbable interference screw design was used as an example.

Results

Cycles to failure of both screw designs varied widely at each load level. The guaranteed minimum number of cycles calculated by tolerance limits was therefore much lower than the mean cycles to failure at any given load level. For example, at a load of 250 N, the predicted mean life for the composite screw and the metal screw was 2513 and 1490 cycles, respectively, whereas the 80/80 tolerance limits (the value that 80% could be expected to achieve with 80% confidence) were only 63 and 68 cycles, respectively. Small reductions in load level gave very large increases in minimally expected life.

Conclusions

Fatigue testing of anterior cruciate ligament reconstructions better shows the wide variation between specimens and the large effect of load levels on expected life. Wide scatter makes mean levels overoptimistic and difficult to interpret. Tolerance limits give estimates that are more conservative and facilitate data interpretation.

Clinical Relevance

A method for testing and analyzing fatigue properties was presented, results of which are more readily interpreted to clinical practice.
In the long run: Biological versus economic rationality
Authors: Thorngate Warren , Tavakoli Mahin
Published: February 2005

Eight computer simulations examined how long hypothetical gamblers could continue gambling without going broke in different games of chance. Gamblers began with a fixed amount of money and paid a fixed ante to play each game. Games had equal expected value but varied in their probability of winning and amount won. When the expected value was zero or positive, gamblers playing low ante, low-risk games (high chances of small wins) had longer runs than did gamblers playing high ante, high-risk games (low chances of big wins). When the expected value was negative, gamblers playing high-risk games had longer runs than gamblers playing low-risk games. The results extend Slobodkin and Rapoport’s concept of biological rationality and explain why people with limited wealth are wise to avoid risks in winning situations and take risks in losing situations, a central principle of prospect theory.
Development of an asset management strategy for a network utility company: Lessons from a dynamic business simulation approach
Authors: Wenzler Ivo
Published: February 2005

Due to market deregulation, network utility companies are forced to transform their asset management to provide better-than-required service quality and maximize financial performance. The author uses a dynamic business simulation (DBS)—a modeling and simulation approach based on system dynamics—to support development of asset management strategies at a couple of network utility companies. The author describes the background and design steps of the DBS approach and evaluates its effectiveness in supporting development of the asset management strategy for one network utility company in the Netherlands, as well as its capacity to become a part of that company’s business capabilities.