bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of Hydrometeor Collection Rates from Exact and Approximate Equations. Part II: Numerical Bounding
Authors: Gaudet Brian J. , Schmidt Jerome M.
Published: January 2007

Past microphysical investigations, including Part I of this study, have noted that the collection equation, when applied to the interaction between different hydrometeor species, can predict large mass transfer rates, even when an exact solution is used. The fractional depletion in a time step can even exceed unity for the collected species with plausible microphysical conditions and time steps, requiring “normalization” by a microphysical scheme. Although some of this problem can be alleviated through the use of more moment predictions and hydrometeor categories, the question as to why such “overdepletion” can be predicted in the first place remains insufficiently addressed. It is shown through both physical and conceptual arguments that the explicit time discretization of the bulk collection equation for any moment is not consistent with a quasi-stochastic view of collection. The result, under certain reasonable conditions, is a systematic overprediction of collection, which can become a serious error in the prediction of higher-order moments in a bulk scheme. The term numerical bounding is used to refer to the use of a quasi-stochastically consistent formula that prevents fractional collections exceeding unity for any moments. Through examples and analysis it is found that numerical bounding is typically important in mass moment prediction for time steps exceeding approximately 10 s. The Poisson-based numerical bounding scheme is shown to be simple in application and conceptualization; within a straightforward idealization it completely corrects overdepletion while even being immune to the rediagnosis error of the time-splitting method. The scheme’s range of applicability and utility are discussed.
Anomalous Wind Circulation Observed during 1997/98 El Niño Using Indian MST Radar
Authors: Rao V. V. M. Jagannadha , Babu A. Narendra , Rao S. Vijaya Bhaskara , Rao D. Narayana
Published: January 2007

Unique facility of measuring vertical winds using Indian mesosphere–stratosphere–troposphere (MST) radar along with horizontal winds enables the study of the atmospheric circulation over Gadanki, India. Several important features are noted while analyzing the wind field. A tropical easterly jet stream of 35 m s−1 strength is seen around 16 km during monsoon season. Relatively strong jetlike northward motion (southerlies) of 5–7 m s−1 is seen around 14 km during winter months. These two maxima in zonal and meridional wind patterns, even though they differ in strength greatly, occur in two contrasting seasons. Downward motion combined with upper-level northward and lower-level southward motion observed during winter in normal years indicates the signature of tropical Hadley circulation over the study region. During the 1997/98 El Niño event, however, an anomalous pattern of winds is seen and Hadley circulation is observed to be weakened.
Effect of Dewfall and Frostfall on Nighttime Cooling in a Small, Closed Basin
Authors: Whiteman C. David , De Wekker Stephan F. J. , Haiden Thomas
Published: January 2007

Series of tethered balloon soundings of temperature and humidity in Austria’s Gruenloch basin (floor elevation 1270 m MSL) on two June days showed that the water vapor mixing ratio fell by 2–3 g kg−1 overnight as dew or frost formed in the basin. After sunrise, the basin atmosphere remoistened as higher humidity was brought down into the basin from above and as evapotranspiration occurred from the basin floor and sidewalls. The latent heat released at night by the dewfall/frostfall was 33%–53% of the overall observed basin sensible heat loss, illustrating the important role of dew and frost formation on the nighttime heat budget of the basin atmosphere. An energy budget equation illustrates the decreasing importance of the latent heat release on the overall basin heat budget as ambient temperatures fall from summer to winter. Because the diurnal temperature range is frequently larger than the late-afternoon dewpoint depression, fog and clouds often form in this basin. The extreme temperature minima that have been previously observed in this basin are expected to be attained only if such cloud moisture is removed. Calculations show that several cloud moisture removal processes may be effective in removing this moisture.
Ethnicity, Class, and Race in the United States
Authors: Priestley George
Published: January 2007

The United States is still organized in terms of a hierarchy of race, gender, and class. In the context of challenges to U.S. hegemony and loss of legitimacy at home, a new hegemonic discourse seeks to replace the racial/class hierarchy with a “color-blind” society made up of a plurality of ethnic groups. Interclass racial alliances have long been engineered by the state to prevent the formation of effective interracial class alliances, and therefore as the “color-blind” society is celebrated the significance of race is reasserting itself nationally and globally. To construct an African-American/Latino class alliance that can strengthen the social justice movement on the way to transforming capitalist racial and gender relations, it will be necessary to unveil and resist this discourse and examine the gendered and racialized spaces that affect Latinos and African-Americans alike.
Arguing and Bargaining in International Negotiations: On the Application of the Frame-Selection Model and its Implications
Authors: Kotzian Peter
Published: January 2007

The aim of this article is to make a conceptual contribution regarding the occurrence of arguing and bargaining in international negotiations and to loosening the unitary-actor assumption underlying state behavior. To explain the occurrence of arguing and bargaining, Esser (2001, 2004) used the frame-selection model developed for individual actors. Arguing and bargaining are seen as frames–fixed combinations of supreme aims, norms, behavioral routines, and symbols. Once activated, a frame largely determines an actor's behavior. Similar to the mechanism proposed by March and Olsen (1998), actors choose a frame given the symbolic information in the situation, but also given the utility associated with a frame. Formally modeling the choice of arguing and bargaining as frames, Esser (2004) treats states as unitary actors and derives several statements about the occurrence of each mode. The additional contribution of this article is the loosening of this assumption and the derivation of its implications. The frames adopted by states are conceptualized as those frames dominant among the individuals involved in any particular negotiation, be it by being members of delegations or national policy networks. There are fundamental differences between the frame of a person and the frame of a state. Further, each component of a state's frame results from a different aggregation process. Only for some frame components, like interests, an established aggregation process exists. This accounts for the differences in the occurrence and effectiveness of arguing and bargaining at the international level.
The Dialectic of Opportunities and Threats and Temporality of Contention: Evidence from the Occupied Territories
Authors: Alimi Eitan Y.
Published: January 2007

Analysis of Palestinian contention in the years leading to the first Intifada illustrates how state action aimed at demobilizing challengers can have the opposite effect. The Palestinian construction of a shared perception of opportunities and threats (a process best thought of as a meaning-laden dialectic of opportunities and threats) can explain this inverse relation between repression and contention. Content analysis of the Palestinian print media suggests that the newspapers' coverage of events in Israel, reflecting deepening domestic Israeli divisions about the continuation of the occupation, framed perceptions of opportunities and threats in a way that called Palestinians to action. This analysis supports the idea that opportunities and threats are not objective features of a political environment, but are, instead, constructed by movement activists.
Where Does Issue Ownership Come From? From the Party or from the Media? Issue-party Identifications in Belgium, 1991-2005
Authors: Walgrave Stefaan , De Swert Knut
Published: January 2007

Although widely used in political science to tackle voting behavior and campaign strategy, the issue-ownership thesis remains untested when it comes to the origins of parties’ identification with specific issues. This article explores where issue ownership comes from and/or how it is maintained. The authors test two possible avenues of issue ownership: the party and the mass media. On one hand, parties’ own external communication may stress specific issues, claiming to be best placed to solve these issues. On the other hand, parties could be identified by the media with certain issues, leading to an implicit association between issue and party. The authors test both propositions, drawing on the case of Belgium, a small consociational democracy in Western Europe. Belgium is a good case to examine issue ownership, as its many parties are identified with many issues. Relying on extensive media data and party evidence, they find that issue ownership is related both to party communications and media coverage. This applies in particular to newer, challenging parties that are strongly identified with their core issues. In general, parties’ older communications are drivers of issue ownership; in contrast, recent media coverage contributes to issue ownership. The direction of the causal arrow remains unsure.
News Content and Americans’ Perceptions of Japan and U.S.-Japanese Relations
Authors: Inoue Yasuhiro , Patterson Dennis
Published: January 2007

Tensions between the United States and Japan over bilateral trade began increasing in the late 1970s, turning sharply negative in the early 1990s before relaxing. This article explores the influences on Americans’ perceptions of Japan during this period. Using agenda-setting and issue-framing theories, we find that concerns over certain aspects of U.S.-Japan relations prompted negative perceptions of Japan.
Adjustment of Inpatient Care Reimbursement for Nursing Intensity
Authors: Welton John M. , Zone-Smith Laurie , Fischer Mary H.
Published: January 2007

The Centers for Medicare and Medicaid Services has begun an ambitious recalibration of the inpatient prospective payment system, the first since its introduction in 1983. Unfortunately, inpatient nursing care has been overlooked in the new payment system and continues to be treated as a fixed cost and billed at a set per-diem “room and board” fee despite the known variability of nursing intensity across different care settings and diagnoses. This article outlines the historical influences regarding costing, billing, and reimbursement of inpatient nursing care and provides contemporary evidence about the variability of nursing intensity and costs at acute care hospitals in the United States. A remedy is proposed to overcome the existing limitations of the Inpatient Prospective Payment System by creating a new nursing cost center and nursing intensity adjustment by DRG for each routine-and intensive-care day of stay to allow independent costing, billing, and reimbursement of inpatient nursing care.
Current displacement (I-Z) spectroscopy-based characterization of nanoscale electro machining (nano-EM) tools
Authors: Virwani K. R. , Rajurkar K. P. , Malshe A. P.
Published: January 2007

A nanoscale die-sinking electro machining (nano-EM) process has been developed on the scanning tunnelling microscope (STM) platform. The consistency of the features machined by the process depends on the quality of the tools used. A simple, fast, and reliable method has been developed using in situ STM to characterize nano-EM tool quality using current displacement (I-Z) spectroscopy curves. The tunnelling current from the tool was monitored as a function of the distance from the workpiece. The distance where the tunnelling current dropped to zero was correlated with the tool's ability to perform nano-EM and atomic resolution surface scans. The tools for which the tunnelling current dropped to zero at 4 Å from the workpiece resulted in consistent nano-EM and atomic resolution topographic scans. A quality criterion based on the I-Z method has been developed for nano-EM tools. This criterion can be extended to define the tool quality in probe-based machining processes and in the emerging field of molecular electronics.
Dual Orbital Effects in N-Philic Cyclizations of Silyl Radicals onto Imines
Authors: Wille Uta , Mucke Eva-Katrin
Published: January 2007

Density functional studies revealed that nucleophilic silyl radicals are able to mask as electrophiles by cyclizing with high preference onto the more electron-rich nitrogen atom of imine C=N double bonds. This remarkable behavior is a result of a combination of SOMO–π* and lone pair (LP)–σ* interactions during the reaction. If the LP is not available due to steric reasons, attack of the Si-radical occurs with slight preference at the carbon atom. This indicates that “dual orbital” interactions are directing the regioselectivity of silyl radical cyclizations.
Solubilization of [60]Fullerene in Water by Aquatic Humic Substances
Authors: Terashima Motoki , Nagao Seiya
Published: January 2007

The solubilization of [60]fullerene (C60) in water in the presence of aquatic humic substances (HSs) was investigated by means of a batch method. The apparent water solubility of C60 in the presence of HSs was 8–540 times higher than that in the blank solution. The size fractionation of C60 in aqueous solutions of HSs showed that the solubilization was due to the dispersion of C60 aggregates as a result of the adsorption of HSs. These results demonstrate that HSs can play a fundamental role in the solubilization of C60 in natural waters.
The Role of Pleiotropy in the Maintenance of Sex in Yeast
Authors: Hill Jessica A , Otto Sarah P
Published: January 2007

In facultatively sexual species, lineages that reproduce asexually for a period of time can accumulate mutations that reduce their ability to undergo sexual reproduction when sex is favorable. We propagated Saccharomyces cerevisiae asexually for ∼800 generations, after which we measured the change in sexual fitness, measured as the proportion of asci observed in sporulation medium. The sporulation rate in cultures propagated asexually at small population size declined by 8%, on average, over this time period, indicating that the majority of mutations that affect sporulation rate are deleterious. Interestingly, the sporulation rate in cultures propagated asexually at large population size improved by 11%, on average, indicating that selection on asexual function effectively eliminated most of the mutations deleterious to sporulation ability. These results suggest that pleiotropy between mutations' effects on asexual fitness and sexual fitness was predominantly positive, at least for the mutations accumulated in this experimental evolution study. A positive correlation between growth rate and sporulation rate among lines also provided evidence for positive pleiotropy. These results demonstrate that, at least under certain circumstances, selection acting on asexual fitness can help to maintain sexual function.
Concerted Evolution Within the Drosophila dumpy Gene
Authors: Carmon Amber , Wilkin Marian , Hassan Jana , Baron Martin , MacIntyre Ross
Published: January 2007

We have determined by reverse Southern analysis and direct sequence comparisons that most of the dumpy gene has evolved in the dipteran and other insect orders by purifying selection acting on amino acid replacements. One region, however, is evolving rapidly due to unequal crossing over and/or gene conversion. This region, called “PIGSFEAST,” or PF, encodes in D. melanogaster 30–47 repeats of 102 amino acids rich in serines, threonines, and prolines. We show that the processes of concerted evolution have been operating on all species of Drosophila examined to date, but that an adjacent region has expanded in Anopheles gambiae, Aedes aegypti, and Tribolium castaneum, while the PF repeats are reduced in size and number. In addition, processes of concerted evolution have radically altered the codon usage patterns in D. melanogaster, D. pseudoobscura, and D. virilis compared with the rest of the dumpy gene. We show also that the dumpy gene is expressed on the inner surface of the micropyle of the mature oocyte and propose that, as in the abalone system, concerted evolution may be involved in adaptive changes affecting Dumpy's possible role in sperm–egg recognition.
Single-Gene Detection and Karyotyping Using Small-Target Fluorescence in Situ Hybridization on Maize Somatic Chromosomes
Authors: Lamb Jonathan C , Danilova Tatiana , Bauer Matthew J , Meyer Julie M , Holland Jennifer J , Jensen Michael D , Birchler James A
Published: January 2007

Combined with a system for identifying each of the chromosomes in a genome, visualizing the location of individual genetic loci by fluorescence in situ hybridization (FISH) would aid in assembling physical and genetic maps. Previously, large genomic clones have been successfully used as FISH probes onto somatic chromosomes but this approach is complicated in species with abundant repetitive elements. In this study, repeat-free portions of sequences that were anchored to particular chromosomes including genes, gene clusters, large cDNAs, and portions of BACs obtained from public databases were used to label the corresponding physical location using FISH. A collection of probes that includes at least one marker on each chromosome in the maize complement was assembled, allowing a small-target karyotyping system to be developed. This set provides the foundation onto which additional loci could be added to strengthen further the ability to perform chromosomal identification in maize and its relatives. The probes were demonstrated to produce signals in several wild relatives of maize, including Zea luxurians, Z. diploperennis, and Tripsacum dactyloides.
The Hsp40 Molecular Chaperone Ydj1p, Along With the Protein Kinase C Pathway, Affects Cell-Wall Integrity in the YeastSaccharomyces cerevisiae
Authors: Wright Christine M , Fewell Sheara W , Sullivan Mara L , Pipas James M , Watkins Simon C , Brodsky Jeffrey L
Published: January 2007

Molecular chaperones, such as Hsp40, regulate cellular processes by aiding in the folding, localization, and activation of multi-protein machines. To identify new targets of chaperone action, we performed a multi-copy suppressor screen for genes that improved the slow-growth defect of yeast lacking the YDJ1 chromosomal locus and expressing a defective Hsp40 chimera. Among the genes identified were MID2, which regulates cell-wall integrity, and PKC1, which encodes protein kinase C and is linked to cell-wall biogenesis. We found that ydj1Δ yeast exhibit phenotypes consistent with cell-wall defects and that these phenotypes were improved by Mid2p or Pkc1p overexpression or by overexpression of activated downstream components in the PKC pathway. Yeast containing a thermosensitive allele in the gene encoding Hsp90 also exhibited cell-wall defects, and Mid2p or Pkc1p overexpression improved the growth of these cells at elevated temperatures. To determine the physiological basis for suppression of the ydj1Δ growth defect, wild-type and ydj1Δ yeast were examined by electron microscopy and we found that Mid2p overexpression thickened the mutant's cell wall. Together, these data provide the first direct link between cytoplasmic chaperone function and cell-wall integrity and suggest that chaperones orchestrate the complex biogenesis of this structure.
The Role Of Nonhomologous End-Joining Components in Telomere Metabolism in Kluyveromyces lactis
Authors: Carter Sidney D , Iyer Shilpa , Xu Jianing , McEachern Michael J , Åström Stefan U
Published: January 2007

The relationship between telomeres and nonhomologous end-joining (NHEJ) is paradoxical, as NHEJ proteins are part of the telomere cap, which serves to differentiate telomeres from DNA double-strand breaks. We explored these contradictory functions for NHEJ proteins by investigating their role in Kluyveromyces lactis telomere metabolism. The ter1-4LBsr allele of the TER1 gene resulted in the introduction of sequence altered telomeric repeats and subsequent telomere–telomere fusions (T–TFs). In this background, Lig4 and Ku80 were necessary for T–TFs to form. Nej1, essential for NHEJ at internal positions, was not. Hence, T–TF formation was mediated by an unusual NHEJ mechanism. Rad50 and mre11 strains exhibited stable short telomeres, suggesting that Rad50 and Mre11 were required for telomerase recruitment. Introduction of the ter1-4LBsr allele into these strains failed to result in telomere elongation as normally observed with the ter1-4LBsr allele. Thus, the role of Rad50 and Mre11 in the formation of T–TFs was unclear. Furthermore, rad50 and mre11 mutants had highly increased subtelomeric recombination rates, while ku80 and lig4 mutants displayed moderate increases. Ku80 mutant strains also contained extended single-stranded 3′ telomeric overhangs. We concluded that NHEJ proteins have multiple roles at telomeres, mediating fusions of mutant telomeres and ensuring end protection of normal telomeres.
DPL-1 DP, LIN-35 Rb and EFL-1 E2F Act With the MCD-1 Zinc-Finger Protein to Promote Programmed Cell Death inCaenorhabditis elegans
Authors: Reddien Peter W , Andersen Erik C , Huang Michael C , Horvitz H Robert
Published: January 2007

The genes egl-1, ced-9, ced-4, and ced-3 play major roles in programmed cell death in Caenorhabditis elegans. To identify genes that have more subtle activities, we sought mutations that confer strong cell-death defects in a genetically sensitized mutant background. Specifically, we screened for mutations that enhance the cell-death defects caused by a partial loss-of-function allele of the ced-3 caspase gene. We identified mutations in two genes not previously known to affect cell death, dpl-1 and mcd-1 (modifier of cell death). dpl-1 encodes the C. elegans homolog of DP, the human E2F-heterodimerization partner. By testing genes known to interact with dpl-1, we identified roles in cell death for four additional genes: efl-1 E2F, lin-35 Rb, lin-37 Mip40, and lin-52 dLin52. mcd-1 encodes a novel protein that contains one zinc finger and that is synthetically required with lin-35 Rb for animal viability. dpl-1 and mcd-1 act with efl-1 E2F and lin-35 Rb to promote programmed cell death and do so by regulating the killing process rather than by affecting the decision between survival and death. We propose that the DPL-1 DP, MCD-1 zinc finger, EFL-1 E2F, LIN-35 Rb, LIN-37 Mip40, and LIN-52 dLin52 proteins act together in transcriptional regulation to promote programmed cell death.
Identification of an Alternative Oxidase Induction Motif in the Promoter Region of the aod-1 Gene in Neurospora crassa
Authors: Chae Michael S , Lin Colin C , Kessler Katherine E , Nargang Cheryl E , Tanton Lesley L , Hahn Leanne B , Nargang Frank E
Published: January 2007

The nuclear aod-1 gene of Neurospora crassa encodes the alternative oxidase and is induced when the standard cytochrome-mediated respiratory chain of mitochondria is inhibited. To study elements of the pathway responsible for alternative oxidase induction, we generated a series of mutations in the region upstream from the aod-1 structural gene and transformed the constructs into an aod-1 mutant strain. Transformed conidia were plated on media containing antimycin A, which inhibits the cytochrome-mediated electron transport chain so that only cells expressing alternative oxidase will grow. Using this functional in vivo assay, we identified an alternative oxidase induction motif (AIM) that is required for efficient expression of aod-1. The AIM sequence consists of two CGG repeats separated by 7 bp and is similar to sequences known to be bound by members of the Zn(II)2Cys6 binuclear cluster family of transcription factors. The AIM motif appears to be conserved in other species found in the order Sordariales.
Kin Recognition inAleochara bilineataCould Support the Kinship Theory of Genomic Imprinting
Authors: Lizé Anne , Cortesero Anne Marie , Atlan Anne , Poinsot Denis
Published: January 2007

Genomic imprinting corresponds to the differential expression of a gene according to its paternal or maternal origin. The kinship theory of genomic imprinting proposes that maternally or paternally inherited genes may be in conflict over their effects on kin differently related along the paternal or maternal line. Most examples supporting the kinship theory of imprinting deal with competition between offspring for maternal resources. However, genomic imprinting may also explain differential behavioral expression toward kin whenever sibs are more related to each other via one parental sex than the other. Unfortunately, nothing is currently known about imprinting associated with a behavioral phenotype in insects. Here we report the first evidence of such a maternally imprinted behavior. We show that the solitary parasitoid larvae of Aleochara bilineata Gyll (Coleoptera; Staphylinidae), which avoid superparasitizing their full sibs, also avoid their cousins when they are related to them through their father, but not when they are related to them through their mother. A genetic kin recognition mechanism is proposed to explain this result and we conclude that genomic imprinting could control the avoidance of kin superparasitism in this species and have a profound influence on decision-making processes.
Phosphorylation and inactivation of glycogen synthase kinase-3 by soluble kit ligand in mouse oocytes during early follicular development
Authors: Liu Lian , Rajareddy Singareddy , Reddy Pradeep , Jagarlamudi Krishna , Du Chun , Shen Yan , Guo Yongzhi , Boman Karin , Lundin Eva , Ottander Ulrika , Selstam Gunnar , Liu Kui
Published: January 2007

Communication between mammalian oocytes and their surrounding granulosa cells through the Kit–Kit ligand (KL, or stem cell factor, SCF) system has been shown to be crucial for follicular development. Our previous studies (Reddy et al. 2005, Liu et al. 2006) have indicated that the intra-oocyte KL–Kit–PI3 kinase (PI3K)–Akt–Foxo3a cascade may play an important role in follicular activation and early development. In the present study, using in situ hybridization and in vitro culture of growing oocytes from 8-day-old postnatal mice, we have demonstrated that another Akt substrate, glycogen synthase kinase-3 (GSK-3), is expressed in growing oocytes. Also, treatment of cultured mouse oocytes with soluble KL not only leads to increased Akt kinase activity in the oocytes, which can phosphorylate recombinant GSK-3 in vitro, but also leads to phosphorylation of oocyte GSK-3α and GSK-3β, which can result in the inactivation of GSK-3 function in oocytes. In addition, we have shown that the regulation of GSK-3α and GSK-3β in cultured oocytes by soluble KL is accomplished through PI3K, since the PI3K-specific inhibitor LY294002 completely abolished the KL-induced phosphorylation of GSK-3α and GSK-3β. Moreover, blockage of the Kit signaling pathway by a Kit function-blocking antibody, ACK2, resulted in reduced phosphorylation of GSK-3. Taken together, our data suggest that the cascade from granulosa cell-derived KL to Kit–PI3K–Akt–GSK-3 in oocytes may take part in regulation of oocyte growth and early ovarian follicular development.
Further delineation of the continuous human neoplastic enterochromaffin cell line, KRJ-I, and the inhibitory effects of lanreotide and rapamycin
Authors: Kidd Mark , Eick Geeta N , Modlin Irvin M , Pfragner Roswitha , Champaneria Manish C , Murren John
Published: January 2007

Small intestinal carcinoids (SICs) are the most prevalent gastrointestinal carcinoid and characterized by local invasion metastasis and protean symptomatology. The proliferative and secretory regulation of the cell of origin, the enterochromaffin (EC) cell has not been characterized. The absence of either a pure preparation of normal EC cells or human EC carcinoid cell lines has hindered the development of therapeutic agents. We therefore further characterized the neoplastic SIC cell line, KRJ-I by assessing its secretory (serotonin (5-HT)) and proliferative responses and defining its log growth phase transcriptome. Electron microscopy demonstrated oval, lobulated nuclei and substance P, and 5-HT-positive cytoplasmic vesicles. RT-PCR detected transcripts for chromogranin A (CHGA), VMAT1 (SLC18A1), tryptophan hydroxylase (TPH1), substance P (TAC1), guanylin (GUCA2A), and SERT (SLC6A4). By immunohistochemistry, all cells were positive for CHGA, SERT, VMAT1, and TPH1. Transcriptome analysis (Affymetrix U133 Plus chips) identified somatostatin SSTR2/3, adrenergic α1C and β1, dopamine D2, nicotinic-type cholinergic A5, A6, B1, muscarinic acetylcholine M4, and 5-HT-2A receptors. The presence of transcripts for SSTR1, SSTR2, and SSTR3 receptors was confirmed by RT-PCR and sequencing. Isoproterenol (ISO) resulted in a dose-dependent increase in intracellular cAMP (EC50=340 nM) and 5-HT (EC50=81 nM) which was completely inhibited by the cAMP antagonist 2′,5′-dideoxyadenosine (10 μM). Preincubation with a SSTR agonist, lanreotide, inhibited Ip-stimulated 5-HT secretion (IC50=420 nM). Both lanreotide (10 nM) and rapamycin (50 nM) inhibited proliferation (20±12 and 35±5% respectively) in serum-free medium whereas gefitinib (1 nM–10 μM) inhibited proliferation at micromolar concentrations. KRJ-I is a neoplastic EC cell line that can be used as an in vitro model of SICs as it will allow elucidation and clarification of the secretory and proliferative mechanism(s) of neoplastic EC cells and the molecular signatures that characterize each of these responses.
Hypothalamic progesterone receptor-A mediates gonadotropin surges, self priming and receptivity in estrogen-primed female mice
Authors: White Mellodee M , Sheffer Irene , Teeter Jennifer , Apostolakis Ede Marie
Published: January 2007

Ovarian progesterone (Prog) is an essential steroid hormone for the secretion of GnRH and reproductive behavior. It exerts primary effects through the progesterone receptor (PR). When analyzed separately in vitro, PR isoforms (PR-A, PR-B) display striking differences in transcriptional activity. The present study was undertaken to determine the in vivo impact of each isoform on hypothalamic function in female mice with ablation of a single isoform, either PR-A or PR-B. To this end, we used single-cell RNA analyses, reverse transcriptase real-time (q)PCR mRNA analyses of punched-out tissue, immunohistochemistry, and reproductive behavior. We provide evidence for the requirement of PR-A in individual ventrolateral ventromedial nucleus (vlVMN) neurons for Prog-facilitated proceptive and receptive behaviors in estrogen benzoate (EB)-primed females and the reciprocal male interactions. We clarify histological and molecular mechanisms of PR isoform activity by showing that (1) PR-A is predominant in individual vlVMN neurons controlling female lordosis circuitry, whilst (2) PR-B is predominant in those VMN subdivisions that provide for amplification of PR-A activity. We go on to demonstrate that PR-A is dominant in the anteroventral periventricular nucleus but not the arcuate nucleus that feed fibers into and around the VMN. In the medial preoptic area, high levels of GnRH RNA in EB-primed PR-A-expressing mice were seen coincident with increased plasma LH levels. Two consecutive GnRH pulses enhanced LH only in primed PR-A-expressing females. In all, the findings are consistent with the hypothesis that hypothalamic PR-A-mediated genomic activities result in reproductive behavior coordinated with ovulation.
The MN1 oncoprotein activates transcription of the IGFBP5 promoter through a CACCC-rich consensus sequence
Authors: Meester-Smoor Magda A , Molijn Anco C , Zhao Yixian , Groen Nicole A , Groffen Cora A H , Boogaard Merel , van Dalsum-Verbiest Diny , Grosveld Gerard C , Zwarthoff Ellen C
Published: January 2007

The IGF-binding protein (IGFBP) family consists of six proteins that are expressed and secreted in different tissues. The proteins are regulators of physiological processes throughout the body by modulating the activity of IGF-I and IGF-II. In this article, we describe the coordinated expression of IGFBP5 and MN1 in meningiomas. MN1 is a transcriptional co-activator and we show that MN1 stimulates the IGFBP5 promoter in Hep3B cells. A CACCC-containing sequence, located 140 bp upstream of the transcription start site of the promoter, is required for MN1 action. This sequence matches with the CACCCAC consensus sequence that was selected in an oligonucleotide selection assay performed for MN1. The CACCC element has also been shown to be important for induction of the IGFBP5 promoter by retinoic acid (RA) and progesterone (Pg). We were unable to confirm the effect of Pg on the promoter in Hep3B and U2-osteosarcoma cells regardless of the presence of MN1. On the other hand, we show that induction of the promoter by RA depends on co-expressed MN1 in Hep3B cells. MN1TEL, a leukemia-related fusion protein containing parts of the MN1 and TEL (ETV6) genes, is capable of stimulating the IGFBP5 promoter but is unable to cooperate with RA in Hep3B cells. This suggests that the effects of RA can be negatively affected in leukemias caused by MN1TEL.
Growth hormone stimulates adipogenesis of 3T3-L1 cells through activation of the Stat5A/5B-PPARγ pathway
Authors: Kawai Masanobu , Namba Noriyuki , Mushiake Sotaro , Etani Yuri , Nishimura Riko , Makishima Makoto , Ozono Keiichi
Published: January 2007

Growth hormone-deficient (GHD) patients show a decreased number of adipocytes, which is normalized by GH replacement, indicating an adipogenic effect of GH. However, the precise mechanisms underlying this effect remain to be clarified. In this study, we investigated the adipogenic effect of GH. GH stimulated MDI (3-isobutyl-1-methylxanthine, dexamethasone, and insulin)-induced adipogenesis of 3T3-L1 cells with early induction of peroxisome proliferator-activated receptors (PPAR)γ2 expression. This adipogenic effect of GH was suppressed by overexpression of Stat5A mutant (Stat5A-Y694F), a transcriptional suppressor for the GH–Stat5A/5B signaling pathway, with the reduction of PPARγ2 expression. Next, we investigated the relationship between Stat5A/5B and CCAAT/enhancer binding protein (C/EBP)β/δ orPPARγ in 3T3-L1 cells. Stat5A/5B stimulated C/EBPβ- and C/EBPδ-induced adipogenesis with enhancement of PPARγ2 expression. In addition, Stat5A/5B enhanced the transcriptional activity of C/EBPβ/δ in the PPARγ gene promoter. Furthermore, Stat5A/5B stimulated PPARγ-induced adipogenesis and enhanced the transcriptional activity of PPARγ. These results suggest that the GH–Stat5A/5B signaling pathway stimulates adipogenesis in cooperation with C/EBPβ/δ and PPARγ. To completely understand the effect of GH, cDNA microarray analysis was performed to screen genes affected by GH during MDI-induced adipogenesis. Among 4277 genes, 18 and 19 genes were up- and down-regulated respectively. cDNA microarray analysis also indicated the up-regulation of PPARγ and the modulation of expression of genes coding for growth factors or growth factor receptors, suggesting that GH stimulates adipogenesis in association with the modulation of cell growth. Thus, the GH–Stat5A/B signaling pathway stimulates adipogenesis through two distinct steps. In addition, cDNA microarray data provide us the further insights underlying the adipogenic effect of GH.
Biological activities of recombinant Manchurian trout FSH and LH: their receptor specificity, steroidogenic and vitellogenic potencies
Authors: Ko Hyeyeon , Park WooDong , Kim Dae-Jung , Kobayashi Makito , Sohn Young Chang
Published: January 2007

Gonadotropins (GTHs), FSH and LH, play central roles in vertebrate reproduction. Here, we report the production of biologically-active recombinant FSH (r-mtFSH) and LH (r-mtLH) of an endangered salmon species, Manchurian trout (Brachymystax lenok), by baculovirus in silkworm (Bombyx mori) larvae. The biological activities of the recombinant hormones were analyzed using COS-7 cell line transiently expressing either amago salmon FSH or LH receptor. The steroidogenic potency of the r-mtFSH and r-mtLH was examined by a culture system using rainbow trout follicles in vitro. In vivo, bioactivity was assessed by measuring ovarian weight, oocyte diameter, and plasma steroid hormone levels in female rainbow trout. Moreover, inducing potency of milt production were examined in vivo using goldfish. Our results demonstrated that the r-mtFSH and r-mtLH were successfully produced in the baculovirus-silkworm system and recognized by their cognate receptors specifically in vitro. The production of estradiol-17β (E2) and testosterone (T) was stimulated by the r-mtFSH and r-mtLH respectively, from the full-grown follicles of rainbow trout, whereas both E2 and T were increased by relatively higher doses of the recombinant hormones from the follicles of the maturing stage. In in vivo assay, injection of the r-mtFSH but not r-mtLH increased ovarian weight, oocyte diameter, and plasma E2 levels in immature rainbow trout. Injection of both r-mtFSH and r-mtLH induced milt production in male goldfish. In conclusion, the present study strongly suggests that the r-mtFSH and r-mtLH have distinct biological properties, such as a specific responsiveness for the cognate receptor, steroidogenic, and vitellogenic activities for ovarian follicles in salmonids. These recombinant FSH and LH may be applied for future studies on the gonadal development and maturation in fishes as well as the endangered salmon species.
Using Earthquake Source Durations along the Sumatra–Andaman Subduction System to Examine Fault-Zone Variations
Authors: Bilek Susan L.
Published: January 2007

The 26 December 2004 great Sumatran–Andaman earthquake in the Indian Ocean caused extensive damage and loss of life from intense shaking and the resulting tsunami. Several studies of this earthquake suggest that portions of the fault ruptured at variable speeds, with both fast and slow rupture velocities observed along the 1200 km long rupture length. Variations in rupture velocity during the earthquake may indicate along-strike variations in megathrust frictional conditions that may influence other earthquakes along the zone. Previous work on global subduction zone systems suggests depth-dependent frictional conditions arising from heterogeneous conditions along the fault. In many of the circum-Pacific subduction zones, shallow earthquakes along the subduction megathrust have longer scaled source durations than deeper earthquakes, possibly resulting from variations in frictional conditions with depth. This study focuses on thrust mechanism earthquakes on the Sumatra– Andaman megathrust, examining aftershocks with Mw >6.0 of the 2004 earthquake, as well as earthquakes that occurred in the region between 1992 and 2004. Source duration, depth, and slip distribution are determined for this set of earthquakes to explore the possibility of both along-strike and depth-dependent variations in source parameters and frictional conditions. There is evidence of depth-dependent source parameters for these events, with longer scaled durations for the shallower earthquakes, consistent with previous global studies. No temporal change is apparent in this relationship, as source parameters for previous large earthquakes are similar to those after the earthquake. Along-strike patterns suggest long-duration character for several earthquakes in the southern portion of the rupture zone but no strong evidence of slow character in the northern portion of the rupture zone. It appears unlikely that any long-term variations in the fault-zone character influenced possible slow rupture of the 2004 earthquake.
New late Pleistocene seismites in a shoreline series including eolianites, north of Rabat (Morocco)
Authors: Plaziat Jean-Claude , Aberkan M’hamed , Reyss Jean-Louis
Published: January 2007

The high coastal cliffs of Sidi Moussa reveal a complex, reliably dated coastal series of Late Pleistocene age. The lagoon, beach and dunes sequence shows repeated seismically induced deformation. These seismites range from the classic hydroplastic load-casts and convolute laminations to a new type of seismite, which corresponds to an oblique fracturation with respect to the horizontal substratum, parallel to the leeside bedding (avalanche foresets) of the overlying dune sequence. Three major earthquakes are thus identified in two high sea-level deposits (lagoonal and paleocliff foot beach), both related to Eemian sea-level peaks (Marine Isotope Stages, MIS 5.53; 5.51), associated with shoreline dune complexes (MIS 5.52; 5.54). The most destructive historical earthquake to affect this Moroccan coast is the so-called Lisbon, 1755 megaseism , the 350 km eastward Atlantic origin of which must be excluded because stratigraphic analysis locally demonstrates repeated co-seismic subsidence. Rather, the tectonic history of the Gharb foreland basin (basement faults reactivation) accounts for the location of major seismicity changing from the Neogene to Pleistocene to the recent times activity.

This example of paleo-earthquake reconstruction demonstrates the need for precise chronology and environmental interpretation of the host sedimentary sequence. The discovery of a new structure-type also exemplifies the unbounded diversity of syn-diagenetic seismites, including those found in early lithified eolianites.
Transient Behavior of Annular Pressure Build-up in HP/HT Wells
Authors: Oudeman P. , Kerem M.
Published: January 2007

Pressure buildup, caused by fluid thermal expansion in sealed annuli of high-presure/high-temperature (HP/HT) wells, can have serious consequences such as casing failure or tubing collapse. To determine whether mitigation was required for a HP/HT development, annular pressures in an appraisal well were studied with a dedicated field test, which consisted of running a pressure/temperature memory gauge in a casing/casing annulus of a well, and testing the well several times during a 3-month period, after which the gauge was retrieved, and the data were read out.

First of all, comparison of the magnitude of the observed annular pressures with the burst and collapse ratings of the casings shows that annular pressure buildup is a serious consideration in casing design. Such design is to be based on theoretical models for annular pressure buildup. The data acquired with the test serve to validate these models.

The data demonstrate that, in general, the theoretical models overpredicted pressure buildup in the annulus. This overprediction was more pronounced at higher temperatures (and pressures) than at lower temperatures, which could not be explained by mechanical factors such as casing ballooning. The influence of these factors was quantified by analyzing the transient pressure response of the annulus. Neither could permanent leakoff of completion fluids explain the discrepancy between theory and test. Leakoff of the annular fluids, which was seen to dominate pressure development during a previous test in a well with a cement shortfall between casings, does not play a significant role in this fully cemented and sealed annulus. This left (1) the properties of the completion fluids differing from the properties of the base fluid (water), and (2) temporary leakoff to near-wellbore fracture systems through the microannuli between cement sheaths and casings as explanations for the observed overprediction. Therefore, estimates on the basis of pure water properties, considering the annulus to be a perfectly pressure-tight vessel, can be considered a worst-case estimate for pressure buildup and a safe basis for design.
True Hybrid Operations Combining Coiled-Tubing Drilling and Conventional Rig Workover Techniques and Practices
Authors: Cassee Udo , Rock Devin , Kara Dan , McLaughlin Sean
Published: January 2007

This paper documents the results of a new stage of development in the application of coiled-tubing drilling (CTD). Combining CTD technology with a conventional jointed-pipe workover capability represents the next-step change in providing low-cost reserves access solutions through selection of the most efficient tool for the application.

Drilling sidetracks using coiled tubing is an established practice in Alaska's North Slope oil fields. During these operations, the use of jointed pipe was avoided, except for running liners, with the CTD rig. A conventional workover rig was the preferred approach to prepare the coiled-tubing candidate well when it required a changeout of production tubing or other workover activity.

In 2001, a North Slope operator evaluated the opportunity to utilize one rig to perform both operations. In 2002, a workover rig was modified to fit the need.

Integrating two established technologies presented many challenges. Specialized equipment, multidisciplinary personnel, and control of overall well cost are just a few of the many parts of the operation to be planned. This paper details the results, problems encountered, solutions, and a quantification of the real benefits achieved combining CTD with a jointed pipe workover.
New Water-Based Mud Balances High-Performance Drilling and Environmental Compliance
Authors: Dye William , d'Augereau Ken , Hansen Nels , Otto Michael , Shoults Larry , Leaper Richard , Clapper Dennis , Xiang Tao
Published: January 2007

A new water-based mud system was successfully introduced as a high-performance, environmentally compliant alternative to oil and synthetic emulsion-based muds (OBM/SBM). Historically, emulsion muds have been the systems of choice when drilling challenging onshore, continental shelf, and deepwater wells to minimize risk, maximize drilling performance, and reduce costs. However, environmental constraints, a high frequency of lost circulation, and the high unit cost of emulsion systems sometimes negate the benefits of their use. Conventional water-based muds (WBM) offer the benefits of environmental compliance, attractive logistics, and a relatively low unit cost but consistently fail to approach the drilling performance of OBM and SBM.

The new high-performance, water-based mud (HPWBM) is designed to close the significant drilling performance gap between conventional WBM and emulsion-based mud systems. The system has undergone extensive field testing on very challenging onshore, deepwater, and continental shelf wells that would otherwise have been drilled with oil or synthetic-based muds. This paper provides a detailed, technical overview of the new system, discusses its inherent environmental advantages, and presents case histories comparing performance to offset wells drilled with emulsion and conventional WBM systems.