bluuebunny/crossref_metadata_2025 huggingface dataset:
Late‐glacial to Holocene environmental changes and climate variability: evidence from Voldafjorden, western Norway
Authors: Sejrup H. P. , Haflidason H. , Flatebø T. , Kristensen D. Klitgaard , Grøsfjeld K. , Larsen E.
Published: August 2002

Sedimentological, micropalaeontological (benthic foraminifers and dinoflagellate cysts), stable isotope data and AMS 14C datings on cores and surface samples, in addition to acoustic data, have been obtained from Voldafjorden, western Norway. Based on these data the late glacial and Holocene sedimentological processes and variability in circulation and fjord environments are outlined. Glacial marine sedimentation prevailed in the Voldafjorden between 11.0 kyr and 9.2 kyr BP (radiocarbon years). In the later part of the Allerød period, and for the rest of the Holocene, there was deposition of fine‐grained normal marine sediments in the fjord basin. Turbidite layers, recorded in core material and on acoustic profiles, dated to ca. 2.1, 6.9–7.6, ca. 9.6 and ca. 11.0 kyr BP, interrupted the marine sedimentation. The event dated to between 6.9 and 7.6 kyr BP probably corresponds to a tsunami resulting from large‐scale sliding on the continental margin off Norway (the Storegga Tsunami).

During the later part of the Allerød period, Voldafjorden had a strongly stratified water column with cold bottom water and warm surface water, reaching interglacial temperatures during the summer seasons. During the Younger Dryas cold event there was a return to arctic sea‐surface summer temperatures, possibly with year‐round sea‐ice cover, the entire benthic fauna being composed of arctic species. The first strong Holocene warming, observed simultaneously in bottom and sea‐surface temperature proxies, occurred at ca. 10.1 kyr BP. Bottom water proxies indicate two cold periods, possibly with 2°C lowering of temperatures, at ca. 10.0 (PBO 1) and at 9.8 kyr BP (PBO 2). These events may both result from catastrophic outbursts of Baltic glacial lake water. The remainder of the Holocene experienced variability in basin water temperature, indicated by oxygen isotope measurements with an amplitude of ca. 2°C, with cooler periods at ca. 8.4–9.0, 5.6, 5.2, 4.6, 4.2, 3.5, 2.2, 1.2 and 0.4–0.8 kyr BP. Changes in the fjord hydrology through the past 11.3 kyr show a close correspondence, both in amplitude and timing of events, recorded in cores from the Norwegian Sea region and the North Atlantic. These data suggest a close relationship between fjord environments and variability in large‐scale oceanic circulation. Copyright © 2001 John Wiley & Sons, Ltd.
Surface‐enhanced Raman spectroscopy as a versatile in situ probe of chemisorption in catalytic electrochemical and gaseous environments
Authors: Weaver Michael J.
Published: August 2002

Some recent applications of surface‐enhanced Raman spectroscopy (SERS) to the characterization of adsorbates at metal surfaces in electrochemical and ambient gaseous systems taken from studies in our laboratory are described with the objective of illustrating the virtues of SERS for examining catalytically relevant interfaces. Emphasis is placed on studies on Pt‐group metal surfaces, prepared by ultrathin film deposition on to SERS‐active gold substrates, reflecting their unique catalytic significance. The surface oxidation of Pt‐group metals in gaseous oxygen and aqueous electrochemical environments is compared, as exemplified for rhodium. The occurrence of a more facile oxidation pathway with gaseous O2 in the presence of water at near‐ambient temperatures is demonstrated, and shown to involve a catalytic electrochemical mechanism, as distinct from the thermal oxidation route in dry O2 which requires elevated temperatures. The central role of the surface potential in such oxidation pathways in both gaseous and conventional electrochemical systems is pointed out. The catalytic activity of such oxidized Pt‐group surfaces in gaseous and electrochemical systems towards the oxidation of methanol and other small organic molecules is outlined on the basis of related SERS data. The application of time‐dependent SERS as a means of diagnosing the presence of adsorbed reaction intermediates is exemplified for the case of carbon monoxide formed during formic acid electrooxidation on rhodium. The formation of reactive π‐bound ethylene, and also non‐reactive ethylidyne, on Pt‐group electrodes upon ethylene chemisorption is also briefly described. Copyright © 2002 John Wiley & Sons, Ltd.
Great mistakes in technology commercialization
Authors: Parker Kevin , Mainelli Michael
Published: August 2002

Annual global investment in technology is enormous. Research & Development (R&D) alone is 1 to 3% of gross domestic product (GDP) in OECD countries, approximately $250 to $350 billion in the 300 largest multinationals and uncounted billions in small organizations.

Advancement in technology transforms lives and without it improvements in productivity and GDP would be limited to increasing labour and material proficiency—finite sources of improvement.

Global GDP per person over the past millennium has risen thirty times and by seven times in the last century alone. This rise has been fuelled by the communication and information age technologies of the last 50 years but, just as importantly, include vaccines, remote sensing, biotechnology, antibiotics, power devices, optics and many others.

Copyright @ 2001 John Wiley & Sons, Ltd.
Development and testing of a comprehensive chemical mechanism for the oxidation of methane
Authors: Hughes K. J. , Turányi T. , Clague A. R. , Pilling M. J.
Published: August 2002

A comprehensive chemical mechanism to describe the oxidation of methane has been developed, consisting of 351 irreversible reactions of 37 species. The mechanism also accounts for the oxidation kinetics of hydrogen, carbon monoxide, ethane, and ethene in flames and homogeneous ignition systems in a wide concentration range. It has been tested against a variety of experimental measurements of laminar flame velocities, laminar flame species profiles, and ignition delay times. The highest sensitivity reactions of the mechanism are discussed in detail and compared with the same reactions in the GRI, Chevalier, and Konnov mechanisms. Similarities and differences of the four mechanisms are discussed. The mechanism is available on the Internet as a fully documented CHEMKIN data file at the address http://www.chem.leeds.ac.uk/Combustion/Combustion.html. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 513–538, 2001
Some methodological problems concerning nonisothermal kinetic analysis of heterogeneous solid–gas reactions
Authors: Budrugeac P. , Segal E.
Published: August 2002

Isoconversional methods, those using only one curve α = α(T) (α is the conversion degree and T is the temperature), and invariant kinetic parameter method were applied to estimate the kinetic parameters from the following nonisothermal data: (1) simulated TG curves for a single reaction; (2) TG curves for thermal degradation of PVC; and (3) TG curves for the dehydration of CaC2O4·H2O. The results obtained by applying various methods for the same system are compared and discussed. Finally, a procedure of kinetic analysis is suggested. Its application could lead to kinetic parameter values that can be used to predict either α = α(t) curves for other heating rates or α = α(T) curves for isothermal conditions. © 2001 John Wiley & Sons, Inc. Int J chem Kinet 33: 564–573, 2001
Assessments of landscape level degradation in southern Ethiopia: pastoralists versus ecologists
Authors: Oba G. , Kotile D.G.
Published: August 2002

This paper compares land degradation assessment techniques using indigenous ecological knowledge (IEK) of the Booran pastoralists and techniques used by ecologists. The study was conducted at landscape and regional levels in southern Ethiopia, where the Booran pastoral production system comprised the Golbo (lowlands), the Dirre (Plateau) and the Liiban production systems (hereafter also referred to as regions). The study, by involving traditional range scouts in evaluating landscape and regional level environmental changes, challenges the notion that IEK is mythical and could not meet scientific rigour. We show that the use of common soil and vegetation indices allows comparisons of land degradation assessments between the IEK of the pastoralists and ecological techniques. Evaluation by traditional range scouts (TRSCs) and range ecologists (REs) on changes in range conditions and trends showed high correlations. Indigenous ecological knowledge was effectively used to determine landscape suitability and potential grazing capacity of individual landscapes and at regional levels. We show different perceptions in interpreting grazing suitability and potential grazing capacity. Management did not change the latter, which is an inherent property of individual landscapes, while the former could be altered. Both TRSCs and REs made comparable predictions on threats to range conditions and trends, but interpreted landscape stability differently. We suggest that integrating IEK in the ecological methods would help identify important perceptions of the pastoralists on effects of land use on local landscapes. Moreover, the value of IEK should also be considered when monitoring landscape level changes as well as when assessing degradation of the grazing lands. We hope the information in this paper will motivate policy‐makers to incorporate the IEK of the pastoralists into decisions on landscape level range rehabilitation. Copyright © 2001 John Wiley & Sons, Ltd.
Histologic evaluation of skin damage after overlapping and nonoverlapping flashlamp pumped pulsed dye laser pulses: A study on normal human skin as a model for port wine stains
Authors: Koster Petra H.L. , van der Horst Chantal M.A.M. , van Gemert Martin J.C. , van der Wal Allard C.
Published: August 2002

Background and Objective

In the treatment of port wine stains (PWS) with the flashlamp pumped pulsed dye laser (FPPDL), no consensus exists about overlapping of pulses. The advantage of overlapping pulses is homogeneous lightening of the PWS; the risk is redundant tissue damage. The aim of this study was to determine the histopathologic effect on human skin of pulsed dye laser pulses with various degrees of overlap, with normal human skin as a model for PWS.

Study Design/Materials and Methods

Eighteen healthy white volunteers were irradiated with pulsed dye laser pulses with increasing radiant exposure and with different degrees of overlap. Biopsy samples were taken and histologically analysed.

Results

Overlapping of pulses on normal human skin enhances depth of vascular damage with approximately 30%. Adjacent pulses also show this effect. We found no histologic signs of serious damage to epidermis or dermal connective tissue by using radiant exposure levels of 6–8 J/cm2, regardless of pulse application.

Conclusions

Reasoning that the mechanism of tissue injury is comparable for normal and PWS skin, we conclude that it is safe to treat PWS with overlapping FPPDL pulses to achieve homogeneous lightening. Lasers Surg. Med. 28:176–181, 2001. © 2001 Wiley‐Liss, Inc.
The interaction of reward contingencies and causality orientation on the introduction of cooperative tactics in buyer–seller negotiations
Authors: Pullins Ellen Bolman
Published: August 2002

This article reports results of an experiment designed to see if reward contingencies and individual differences in causality orientation can interact to affect the frequency with which buyers and sellers introduce cooperative tactics into a sales negotiation. A face‐to‐face simulation is employed to consider these effects. A 2 × 2 ANOVA (task‐contingent/task‐noncontingent rewards × control/autonomy orientation) tests this interaction. These two factors interact to affect cooperation. A buyer or seller with an autonomous causality, in a situation with task‐noncontingent rewards, is most likely to introduce cooperative negotiation tactics. Task‐noncontingent rewards are more effective than task‐contingent rewards for autonomous causality buyers and sellers, but not for control causality buyers and sellers. © 2001 John Wiley & Sons, Inc.
Improving an optimization‐based framework for sensitivity analysis in multi‐criteria decision‐making
Authors: Proll L.G. , Salhi A. , Rios Insua D.
Published: August 2002

The framework for sensitivity analysis in discrete multi‐criteria decision analysis developed by Rios Insua and French allows simultaneous variation of all parameters and applies to many paradigms for decision analysis. However, its computational load may inhibit use, particularly in the context of a decision conference where results are required in near real time. In order to improve on the current algorithm and its implementation, we investigate, on the one hand, an opportunistic approach aimed at reducing the number of optimization problems solved in the original framework and, on the other, an alternative framework based on distance analysis. Computational results on linear and bilinear models are reported. Copyright © 2001 John Wiley & Sons, Ltd.
Selective loss of striatal preprotachykinin neurons in a phenocopy of Huntington's disease
Authors: Richfield Eric K. , Vonsattel Jean‐Paul , MacDonald Marcy E. , Sun ZhiQiang , Deng Yun‐Ping P. , Reiner Anton
Published: August 2002

Phenocopies of Huntington's disease (HD) are individuals with a family history, clinical symptoms, and occasionally pathological evidence of HD but without an expanded CAG repeat within the HD gene. We report on an HD phenocopy with selective loss of preprotachykinin (PPT) neurons, dysfunction of surviving PPT neurons, preservation of preproenkephalin (PPE) neurons within the striatum, and greater loss of immunohistochemical staining for substance P in terminals of striatal neurons projecting to the substantia nigra, than in those projecting to the internal pallidal segment. This case demonstrates the existence of one type of striatal lesion that may produce a clinical picture similar to HD, and raises the possibility of a rare hereditary disease that mimics HD. © 2002 Movement Disorder Society.
Dynamic balance function in phasic cervical dystonia following Botulinum toxin therapy
Authors: Müller Jörg , Ebersbach Georg , Wissel Jörg , Poewe Werner
Published: August 2002

Previous research by our group revealed normal dynamic balance function in pure tonic cervical dystonia (CD) with impaired equilibrium in phasic CD patients investigated at least 3 months following Botulinum toxin (BtxA) treatment. The current study was performed to determine whether impaired dynamic equilibrium in phasic CD is influenced by symptomatic treatment with BtxA. Dynamic balance was tested in 20 patients with phasic CD on a dynamic platform with a cylindrical curved base (stabilometer) 4 weeks following BtxA treatment. Balance was assessed by the linear displacement of the platform and the maximum amplitude of platform displacement with open and closed eyes and compared with pre‐BtxA data. Despite a clinically significant BtxA‐induced reduction of phasic head movements, none of the platform measures improved significantly. In addition, there was no correlation between the BtxA‐induced clinical improvement and changes in any of the dynamic balance measures pre‐ vs. post‐BtxA. In conclusion, the persistent dynamic balance impairment after effective BtxA therapy may indicate that disequilibrium in phasic CD does not simply reflect disturbed vestibular input from repetitive head oscillations, but argues in favour of different sensorimotor processing in tonic and phasic CD. © 2001 Movement Disorder Society.
Equivalent‐circuit model for slit discontinuity and its application to the filter in a CPW structure
Authors: Bae Joung‐Sun , Lee Jong‐Chul , Lee Byungje , Kim Jong‐Heon , Kim Nam‐Young
Published: August 2002

In this letter, a transverse slit within the signal line in a coplanar waveguide (CPW) structure is modeled as series inductance and parallel capacitance, and the simple formulas for the capacitance and the inductance are introduced. Also, a broadband harmonic‐suppressed filter (12.5–50 GHz), a band‐rejection filter, and a finite‐ground (FG)–CPW low‐pass filter (LPF) with this structure are demonstrated. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 31: 426–428, 2001.
Combination of antennas and solar cells for satellite communications
Authors: Vaccaro S. , Torres P. , Mosig J. R. , Shah A. , Skrivervik A. K. , Zürcher J.‐F. , de Maagt P. , Gerlach L.
Published: August 2002

A new principle of antenna‐combining amorphous silicon solar cells and printed patches is presented. The antenna is designed, taking into account the solar cells that provide power to an MMIC amplifier. A 2×4 antenna array is presented, working at a frequency of 3.76 GHz with a bandwidth of 16% and a gain of 13 dBi (passive) and up to 30 dBi (active). The a–Si:H solar cells supply 5 V and 100 mW at AM1.5. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 11–16, 2001.
Multiplex RT‐PCR assay for the detection of major fusion transcripts in Taiwanese children with B‐lineage acute lymphoblastic leukemia
Authors: Liang Der‐Cherng , Shih Lee‐Yung , Yang Chao‐Ping , Hung Iou‐Jih , Chen Shu‐Huey , Jaing Tang‐Her , Liu Hsi‐Che , Chang Wan‐Hui
Published: August 2002

Background

The classification of B‐lineage acute lymphoblastic leukemia (ALL) by specific chromosomal translocations may have prognostic implications. Reverse transcriptase‐polymerase chain reaction (RT‐PCR) assay is a useful tool for the detection of fusion transcript resulting from specific chromosomal translocation of the leukemic cells. In general, fusion transcripts are determined individually, a process which is labor intensive in order to detect all major fusion transcripts.

Procedure

We use a multiplex RT‐PCR assay to detect both the CML‐ and ALL‐type BCR‐ABL transcripts of the t(9;22), all described variants of the E2A‐PBX1 transcripts of t(1;19), the MLL‐AF4 transcripts of t(4;11), and all described variants of TEL‐AML1 (also termed ETV6‐CBFA2) of the cryptic t(12;21) in 165 leukemic samples at diagnosis.

Results

The study yielded a completely concordant result with those obtained by the individual RT‐PCR assay. In this cohort of Taiwan children, the relative frequencies of the four translocations of B‐lineage ALL were as following: 6% with ALL‐type t(9;22)/BCR‐ABL, 7% t(1;19)/E2A‐PBX1, 3% t(4;11)/MLL‐AF4, and 18% t(12;21)/TEL‐AML1, comparable to those in the Western countries.

Conclusion

Multiplex RT‐PCR assay is an efficient, sensitive, accurate, and cost‐effective diagnostic tool, which will likely improve our ability in accurately and rapidly risk‐stratifying children with ALL. Med Pediatr Oncol 2002;39:12–17. © 2002 Wiley‐Liss, Inc.
Scedosporium infection in immunocompromised patients: Successful use of liposomal amphotericin B and itraconazole
Authors: Barbaric D. , Shaw P.J.
Published: August 2002

Background

Invasive fungal disease is a major cause of death in immunocompromised patients. The filamentous fungus Scedosporium consists of two species, S. prolificans and S. apiospermum, which can cause infections in immunocompromised patients that are often fatal. A significant feature of this pathogen is its broad resistance to many antifungal agents, including amphotericin B.

Procedure and Results

Five cases of infection with Scedosporium spp. occurred in patients with haematologic malignancies over a 10‐month period. Three patients with S. prolificans were severely immunosuppressed and neutropenic; two were in relapse and another was early post‐matched unrelated bone marrow transplant. All three died despite treatment with various combinations of amphotericin B and itraconazole. Two patients who were less immunosuppressed and had a normal neutrophil count developed S. apiospermum infection. Both were successfully treated with liposomal amphotericin B and itraconazole.

Conclusions

Disseminated infection in immunocompromised hosts with Scedosporium spp. is often fatal. However, in patients with a lesser degree of immunocompromise and particularly in those infected with the less virulent S. apiospermum, intensive antifungal therapy with liposomal amphotericin B and itraconazole may be associated with complete eradication of infection. Med Pediatr Oncol 2001;37:122–125. © 2001 Wiley‐Liss, Inc.
Bacteraemia in a paediatric oncology unit in South Africa
Authors: van de Wetering M.D. , Poole J. , Friedland I. , Caron H.N.
Published: August 2002

Objectives

To identify the morbidity and mortality due to infections in a South African paediatric oncology unit, and to identify risk factors associated with first bacteraemic episodes in this unit.

Procedure

A retrospective cohort study was done in a large regional referral paediatric cancer centre from 1991–1995, of all consecutive patients with culture proven bacteraemia. Eighty‐three oncology patients were studied (median age 4.0 years) in whom a total of 200 episodes of bacteraemia were recorded, of which 83 first bacteraemic episodes.

Results

Of the 200 episodes 70% were caused by Gram‐positive organisms, 20% by Gram‐ negative organisms and 10% by fungal organisms. Organisms associated with high mortality were Gram‐negative organisms (Acinetobacter spp., Pseudomonas aeruginosa, Klebsiella species), and fungal organisms, (Candida parapsilosis). Seventeen out of 200 episodes ended in death of the patient. In 59% of patients Hickman catheters were in situ. The mean incidence of catheter related bacteraemia's was 3.3 episodes per 1000 catheter days. Seventy percent of first bacteraemic episodes occured within 50 days after placement of the catheter. The generalized estimation equations model revealed that more Gram‐negative infections occurred in the presence of a Hickmancatheter (odds ratio 2.2, 95% CI 1.0–5.0). The presence of neutropenia and the use of parenteral nutrition were not associated with specific bacteraemic patterns.

Conclusions

Including all bacteraemic episodes in this cohort study a high incidence of fungal infections occurred of which 64% occurred with a Hick‐mancatheter in situ. Candida parapsilosis had a higher incidence than reported in other centres. Secondly looking at first bacteraemic episodes a high incidence of Gram‐negative infections was observed especially in the presence of a Hickmancatheter. Med Pediatr Oncol 2001;37:525–531. © 2001 Wiley‐Liss, Inc.
Cholestasis, sclerosing cholangitis, and liver transplantation in Langerhans cell histiocytosis
Authors: Braier Jorge , Ciocca Mirta , Latella Antonio , de Davila Maria G. , Drajer Marina , Imventarza Oscar
Published: August 2002

Objective

To analyze features and outcomes of cholestasis, sclerosing cholangitis (SC), and liver transplantation (LTx) in patients with Langerhans cell Histiocytosis (LCH) between October 1987 and June 1999.

Study design

Of 182 cases with LCH, 36 had hepatic involvement and 12 of those presented with cholestasis. These 12 were the focus of our study. Their median age was 23 months (range: 3–36). Hepatomegaly or hepatosplenomegaly was found in 11 of the 12; elevations of alkaline phosphatase, transaminases, gamma glutamyl transpeptidase (GGT), and less frequently direct bilirubin were detected. Sonography, liver biopsy, and cholangiography were consistent with the diagnosis of SC in 11 patients. None of the biopsies revealed Langerhans cells (LC). Frequently associated lesions of skin, bone, and ear were noted. Early patients were treated with Vinblastine/prednisone for 8 weeks, later patients with the LCH I and LCH II protocols of the Histiocyte Society (HS).

Results

Median follow‐up was 28 months (range: 10–86). Three patients improved and remained without signs of progressive SC at 27, 32, and 86 months. Nine had progressive liver sequelae resistant to chemotherapy. Of these nine, five received LTx, three died before LTx with progressive SC, and one awaits LTx. Three LTx patients survive without disease reactivation 14, 25, and 37 months post‐transplant. Two patients died less than one month after LTx, due to renal failure and sepsis in the first patient and bowel volvulus with perforation followed by sepsis in the second one.

Conclusions

SC is a frequent and usually progressive sequela of multisystem LCH in our institution. LTx has become the treatment of choice for the majority of patientsand should be considered early in cases with severe hepatic involvement. Med Pediatr Oncol 2002;38:178–182. © 2002 Wiley‐Liss, Inc.
1H and 13C NMR spectral assignments of 2,4‐diaryl‐substituted cycloalkyl[d]pyrimidines
Authors: Herrera Antonio , Martínez‐Alvarez Roberto , Chioua Mourad , Sánchez Ángel , Molero Dolores , Chioua Rachid
Published: August 2002

The proton and carbon spectra of new 2,4‐diaryl‐substituted cycloalkyl[d]pyrimidines prepared in a simple one‐pot reaction, are reported. Copyright © 2002 John Wiley & Sons, Ltd.
An NMR tool for cyclodextrin selection in enantiomeric resolution by high‐performance liquid chromatography
Authors: Laverde Antonio , da Conceição Gelson J. A. , Queiroz Sonia C. N. , Fujiwara Fred Y. , Marsaioli Anita J.
Published: August 2002

Complexation‐induced chemical shifts and diffusion coefficients (HR‐DOSY) of enantiomers with native and derivatized cyclodextrins were used for calculations of the apparent binding constants of three cyclohexanone inclusion complexes. Correlations between these data and high‐performance liquid chromatography were established, revealing that this approach can be applied as an alternative method to predict enantiomeric discrimination. Copyright © 2002 John Wiley & Sons, Ltd.
Characterization of para‐substituted benzamidoximes and benzamidinium salts by 15N NMR spectroscopy
Authors: Girreser U. , König M. , Clement B.
Published: August 2002

15N NMR data for a series of 12 para‐substituted benzamidoximes and benzamidinium salts were determined in dimethyl sulfoxide. For the amino group of benzamidoximes 1J(N,H) coupling constants were determined using polarization transfer techniques; the other 15N atoms were not detectable owing to fast exchange processes and, thus, standard proton noise decoupled spectra had to be measured. The 15N NMR chemical shifts of the oxime‐type nitrogen atom and the benzamidinium amino group (with two exceptions) correlate with Hammett σ° values (r2>0.95). 15N NMR shift data are a suitable and sensitive means for characterizing far‐ranging electronic substituent effects in these functional groups. Additionally, 13C NMR data in dimethyl sulfoxide solution are given. All spectroscopic data will be used for investigations into the mechanisms of the enzymes involved in the metabolic cycle of oxidation and reduction of benzamidines and benzamidoximes. Copyright © 2002 John Wiley & Sons, Ltd.
Evidence that multifunctional calcium/calmodulin‐dependent protein kinase II (CaM KII) participates in the meiotic maturation of mouse oocytes
Authors: Su You‐Qiang , Eppig John J.
Published: August 2002

Calcium‐dependent signaling pathways are thought to be involved in the regulation of mammalian oocyte meiotic maturation. However, the molecular linkages between the calcium signal and the processes driving meiotic maturation are not clearly defined. The present study was conducted to test the hypothesis that the multi‐functional calcium/calmodulin‐dependent protein kinase II (CaM KII) functions as one of these key linkers. Mouse oocytes were treated with a pharmacological CaM KII inhibitor, KN‐93, or a peptide CaM KII inhibitor, myristoylated AIP, and assessed for the progression of meiosis. Two systems for in vitro oocyte maturation were used: (1) spontaneous gonadotropin‐independent maturation and (2) follicle‐stimulating hormone (FSH)‐induced reversal of hypoxanthine‐mediated meiotic arrest. FSH‐induced, but not spontaneous germinal vesicle breakdown (GVB) was dose‐dependently inhibited by both myristoylated AIP and KN‐93, but not its inactive analog, KN‐92. However, emission of the first polar body (PB1) was inhibited by myristoylated AIP and KN‐93 in both oocyte maturation systems. Oocytes that failed to produce PB1 exhibited normal‐appearing metaphase I chromosome congression and spindles indicating that CaM KII inhibitors blocked the metaphase I to anaphase I transition. Similar results were obtained when the oocytes were treated with a calmodulin antagonist, W‐7, and matured spontaneously. These results suggest that CaM KII, and hence the calcium signaling pathway, is potentially involved in regulating the meiotic maturation of mouse oocytes. This kinase both participates in gonadotropin‐induced resumption of meiosis, as well as promoting the metaphase I to anaphase I transition. Further evidence is therefore, provided of the critical role of calcium‐dependent pathways in mammalian oocyte maturation. Mol. Reprod. Dev. 61:560–569, 2002. © 2002 Wiley‐Liss, Inc.
Differential cellular compartmentalization of the nuclear receptor SpSHR2 splicing variants in early sea urchin embryos
Authors: Kontrogianni‐Konstantopoulos Aikaterini , Flytzanis Constantin N.
Published: August 2002

SpSHR2 is a member of the nuclear receptor superfamily, expressed in embryos, larvae, and adult tissues of sea urchin. During embryonic development, two receptor isoforms are produced via alternative splicing. One exhibits the typical structure of nuclear receptors (SpSHR2‐full length), whereas the other is missing the entire LBD (SpSHR2‐splice variant). DNA‐constructs encoding these isoforms and two additional in vitro generated deletion mutants were engineered in an expression vector carrying the myc‐tag. Expression of the tagged isoforms in S. purpuratus embryos showed that the exogenous SpSHR2 full‐length protein displays a similar subcellular localization as the endogenous receptor. In early cleavage stages (4‐cells), the full‐length isoform is predominantly localized in the nucleus, whereas two cell divisions later (16‐cells) protein accumulations are detected in both the nucleus and cytoplasm. To the contrary, the SpSHR2‐splice variant is confined in the embryonic nuclei both at 4‐ and 16‐cell stage embryos. Analysis of the intracellular distribution of two receptor mutants, one having a deletion within the DBD (ΔP) and the other a truncation of the C‐terminal F‐domain (ΔF), revealed that ΔP is localized similarly to full‐length receptor, whereas ΔF is maintained in the nucleus, similar to the SpSHR2 splice variant. Investigation of the DNA binding and dimerization properties of the two SpSHR2 isoforms demonstrated that they recognize and bind to a DR1‐element as monomers, whereas ΔP does not bind DNA and ΔF binds to DR1 poorly. These results suggest that the receptor's putative LBD is responsible for the differential subcellular localization of the two natural SpSHR2‐isoforms in early development. Mol. Reprod. Dev. 60: 147–157, 2001. © 2001 Wiley‐Liss, Inc.
Mouse oocytes and preimplantation embryos bear the two sub‐units of interferon‐gamma receptor
Authors: Truchet Sandrine , Wietzerbin Juana , Debey Pascale
Published: August 2002

Cytokines and growth factors play important roles in implantation and maintenance of pregnancy, but also during early development. Among them interferon‐gamma (IFNγ) is highly expressed by mammalian trophoblast cells during implantation and seems to be involved in some cases of pregnancy loss. In the present study we investigated the possible presence of IFNγ receptors (IFNGR) on mouse oocytes and preimplantation embryos. The two receptor chains IFNγRα (IFNGR‐1) and IFNγRβ (IFNGR‐2) have been detected by indirect immunofluorescence at the surface of mouse oocytes (in germinal vesicle and metaphase II stages), as well as at all stages of in vitro embryo development from the one‐cell to blastocyst stage. IFNGR appeared to colocalize partly with ganglioside GM1 at the cell surface of oocytes and embryos, indicating a possible preferential localization of this receptor in “rafts” microdomains. This was analyzed in more detail using software developed in the laboratory. IFNγ was found to bind to its receptor at all stages analyzed. RT‐PCR and Southern blot experiments confirmed the presence of the transcriptionally regulated IFNGR‐2 chain mRNA, in mouse oocytes and preimplantation embryos. These results show, for the first time, that mouse oocytes and preimplantation embryos bear a complete and theoretically functional IFNGR, suggesting that this cytokine could play a role during early development.Mol. Reprod. Dev. 60: 319–330, 2001. © 2001 Wiley‐Liss, Inc.
Expression of spermadhesin genes in porcine male and female reproductive tracts
Authors: Ekhlasi‐Hundrieser Mahnaz , Sinowatz Fred , De Wilke Irene Greiser , Waberski Dagmar , Töpfer‐Petersen Edda
Published: August 2002

Spermadhesins, secretory proteins of the male genital tract, constitute the bulk of seminal plasma proteins in pig. The nucleotide sequences of spermadhesins AWN, AQN‐1, and AQN‐3 from the cDNAs, derived from seminal vesicles, were determined. The coding sequences of spermadhesins revealed an overall sequence similarity of 40% at nucleotide level. Expression of spermadhesins (AWN, AQN‐1, AQN‐3, PSP‐I, and PSP‐II) in porcine male and female reproductive tracts were studied by means of RT‐PCR and immunological approaches. All spermadhesins are transcribed and translated in seminal vesicles and prostate. In caudal epididymis mRNA transcripts of all spermadhesins have been detected by RT‐PCR. PSP‐I showed additional signals in caput epididymis and rete testis. Translation can be detected only for AWN in tissue extracts by SDS–PAGE and Western blotting. Remarkably, AWN is the only spermadhesin that is also expressed in the uterus, the uterotubal junction, and the oviduct of the female genital tract as shown by RT‐PCR, cDNA‐sequencing, and immunological analysis. In sows at estrus and interestrus, in gilts and gilts 12 hr after insemination no obvious differences were noticed in the pattern of AWN‐immunoreactivity in epithelial cells either of the uterotubal junction, isthmus, or ampulla. While strong staining was observed in the superficial uterine glands and in the glands of the uterotubal junction during estrus, in diestrus this declined distinctly. The role of spermadhesins in relation to their expression is discussed. Mol. Reprod. Dev. 61: 32–41, 2002. © 2002 Wiley‐Liss, Inc.
Expression of 3β‐hydroxysteroid dehydrogenase in early bovine embryo development
Authors: Chiappe M.E. , Lattanzi M.L. , Colman‐Lerner A.A. , Barañao J.L. , Saragüeta P.
Published: August 2002

We analyzed the presence of 3β‐Hydroxysteroid Dehydrogenase/Δ5→4‐isomerase enzyme (3β‐HSD) activity, a key enzyme of the steroid metabolic pathway, the mRNA of this enzyme, and the steroid metabolism in in vitro produced bovine embryos. 3β‐HSD activity was detected in in vitro matured oocytes (74.4 ± 1.4%), 1‐cell (72.9 ± 6.1%), 2‐cell (61.8 ± 7.4%), 8‐cell (50 ± 5%), morulae (50.8 ± 2.6%), blastocysts (94.4 ± 3%), and hatched blastocysts (100 ± 0%) meanwhile the 4‐cell stage showed a significant reduction (16.7 ± 4.7%). When total embryonic RNA of different stages was subjected to RT‐PCR assays, the mRNA of 3β‐HSD was found to be present in all developmental stages of in vitro produced bovine embryos, from the oocyte to the blastocyst, with a marked decrease at the 4‐cell stage. To determine whether the temporal pattern of enzyme activity was dependent on the maternal to zygotic transition, embryos were incubated in the presence of a transcription inhibitor, α‐amanitin. The reappearance of the enzyme activity after the 4‐cell stage was blocked in α‐amanitin treated embryos, indicating the requirement of embryonic transcription. On the other hand, the embryonic steroid metabolism was tested by incubating blastocyst with tritiated pregnenolone. Analysis of the metabolites by TLC indicated the production of a compound with a mobility identical to progesterone. These results described the expression of the 3β‐HSD and the activity of this metabolic enzyme in bovine oocytes and preimplantation embryos, suggesting that steroids may act as autocrine effectors on preimplantation embryo development. Mol. Reprod. Dev. 61: 135–141, 2002. © 2002 Wiley‐Liss, Inc.
Selective three‐dimensional visualization of the coronary arterial lumen using arterial spin tagging
Authors: Stuber Matthias , Börnert Peter , Spuentrup Elmar , Botnar René M. , Manning Warren J.
Published: August 2002

Conventional coronary magnetic resonance angiography (MRA) techniques display the coronary blood‐pool along with the surrounding structures, including the myocardium, the ventricular and atrial blood‐pool, and the great vessels. This representation of the coronary lumen is not directly analogous to the information provided by x‐ray coronary angiography, in which the coronary lumen displayed by iodinated contrast agent is seen. Analogous “luminographic” data may be obtained using MR arterial spin tagging (projection coronary MRA) techniques. Such an approach was implemented using a 2D selective “pencil” excitation for aortic spin tagging in concert with a 3D interleaved segmented spiral imaging sequence with free‐breathing, and real‐time navigator technology. This technique allows for selective 3D visualization of the coronary lumen blood‐pool, while signal from the surrounding structures is suppressed. Magn Reson Med 47:322–329, 2002. © 2002 Wiley‐Liss, Inc.
Cerebral T1ρ relaxation time increases immediately upon global ischemia in the rat independently of blood glucose and anoxic depolarization
Authors: Kettunen Mikko I. , Gröhn Olli H.J. , Penttonen Markku , Kauppinen Risto A.
Published: August 2002

Time‐dependent changes of T1 in the rotating frame (T1ρ), diffusion, T2, and magnetization transfer contrast on cardiac arrest‐induced global ischemia in rat were investigated. T1ρ, as acquired with spin lock amplitudes >0.6 G, started to increase 10–20 sec after cardiac arrest followed by an increase within 3–4 min to a level that was 6–8% greater than in normal brain. The ischemic T1ρ response coincided with the drop of water diffusion coefficient in normoglycemic animals. However, unlike the rate of diffusion, the kinetics of T1ρ were not affected by either preischemic hypoglycemia or hyperglycemia. Similar to diffusion, the kinetics of anoxic depolarization were dependent on preischemic blood glucose levels. Ischemia caused a reduction in the Hahn spin echo T2 as a result of blood oxygenation level‐dependent (BOLD) effect; maximal negative BOLD seen by 40 sec. In the animals injected with an ironoxide particle contrast agent, AMI‐227, prior to the insult, both T1ρ and T2 immediately increased in concert on induction of ischemia. In contrast to the T1ρ and diffusion changes, a much slower change in magnetization transfer contrast was evident over the first 20 min of ischemia. These data demonstrate that T1ρ immediately increases following ischemia and that the pathophysiological mechanisms affecting this relaxation time may not directly involve magnetization transfer. The mechanisms prolonging T1ρ differ from those affecting water diffusion with respect to their sensitivities to glucose and are apparently independent of membrane depolarization. Magn Reson Med 46:565–572, 2001. © 2001 Wiley‐Liss, Inc.
USPIO‐enhanced dynamic MRI: Evaluation of normal and transplanted rat kidneys
Authors: Yang Dewen , Ye Qing , Williams Mangay , Sun Ying , Hu Tom C.‐C. , Williams Donald S. , Moura José M.F. , Ho Chien
Published: August 2002

To evaluate first‐pass renal perfusion with ultrasmall superparamagnetic iron oxide (USPIO) particles by MRI, 40 normal rats (20 Dark Agouti (DA) rats and 20 Brown Norway (BN) rats) and 16 transplanted rats (12 allografts and four isografts) were studied on day 4 post‐transplantation with different USPIO doses (3.0–18.1 mg Fe/kg/body weight). All animals underwent 128 consecutive snapshot fast low‐angle shot (FLASH) coronal dynamic studies in 43 s. In the normal rats, a larger maximum signal decrease (MSD) in the cortex and the outer medulla is observed with an increasing dose of USPIO particles (P < 0.01). No significant differences were observed between the right and left kidneys at all doses studied. Higher MSD, time of occurrence of MSD (tMSD), and wash‐in slope appear with higher doses of USPIO particles. The dynamic curves for DA rats show similar shapes when compared to those for BN rats. In the transplanted rats, allograft kidneys show lower MSD, longer tMSD, and lower wash‐in slope compared to those in the normal kidneys. Isograft kidneys show perfusion patterns similar to those of normal kidneys in the cortex and the outer medulla. Histopathology indicates acute vascular rejection in all allografts and normal kidney architecture in all isografts. The results clearly show good agreement between the renal graft perfusion measurements and histopathological changes associated with rejection. This work also introduces a new signal analysis methodology for the automatic detection of transplanted organ rejection. This method compares the dynamics of the intrarenal signal intensities for native and transplanted kidneys. A quantitative measurement to detect significant differences between these signals was developed, and showed that this technique exhibits good performance in identifying renal rejection. Magn Reson Med 46:1152–1163, 2001. © 2001 Wiley‐Liss, Inc.
Brachial plexus neoplastic lesions assessed by conduction study of medial antebrachial cutaneous nerve
Authors: Seror Paul
Published: August 2002

Two cases of neoplastic involvement of the lower brachial plexus are reported. This condition was due to recurrence of lymphoma in one case and to axillary node spread of breast cancer in the other. The neuropathic origin and the location of the lesion in the lower brachial plexus between the T‐1 root and the axilla was demonstrated by the presence of abnormalities on testing of the medial antebrachial cutaneous nerve in the symptomatic upper limb and comparing it to the healthy one. All other electrodiagnostic tests were normal. Such a finding suggests the need for imaging of the lower brachial plexus region by computed tomography or magnetic resonance imaging. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1068–1070, 2001
A dual criteria sequencing problem with earliness and tardiness penalties
Authors: Leung Joseph Y.‐T.
Published: August 2002

We consider the problem of sequencing n jobs on a single machine, with each job having a processing time and a common due date. The common due date is assumed to be so large that all jobs can complete by the due date. It is known that there is an O(n log n)‐time algorithm for finding a schedule with minimum total earliness and tardiness. In this article, we consider finding a schedule with dual criteria. The primary goal is to minimize the total earliness and tardiness. The secondary goals are to minimize: (1) the maximum earliness and tardiness; (2) the sum of the maximum of the squares of earliness and tardiness; (3) the sum of the squares of earliness and tardiness. For the first two criteria, we show that the problems are NP‐hard and we give a fully polynomial time approximation scheme for both of them. For the last two criteria, we show that the ratio of the worst schedule versus the best schedule is no more than ${3\over 2}$. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 422–431, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10020
A risk function for the stochastic modeling of electric capacity expansion
Authors: Marín A. , Salmerón J.
Published: August 2002

We present a stochastic optimization model for planning capacity expansion under capacity deterioration and demand uncertainty. The paper focuses on the electric sector, although the methodology can be used in other applications. The goals of the model are deciding which energy types must be installed, and when. Another goal is providing an initial generation plan for short periods of the planning horizon that might be adequately modified in real time assuming penalties in the operation cost. Uncertainty is modeled under the assumption that the demand is a random vector. The cost of the risk associated with decisions that may need some tuning in the future is included in the objective function. The proposed scheme to solve the nonlinear stochastic optimization model is Generalized Benders' decomposition. We also exploit the Benders' subproblem structure to solve it efficiently. Computational results for moderate‐size problems are presented along with comparison to a general‐purpose nonlinear optimization package. © 2001 John Wiley & Sons, Inc. Naval Research Logistics 48:662–683, 2001
A comparative fMRI study: T2*‐weighted imaging versus R2* mapping
Authors: Wennerberg Anders B. A. , Jonsson Tomas , Forssberg Hans , Li Tie‐Qiang
Published: August 2002

Functional magnetic resonance imaging experiments were performed in human motor cortex at 1.5 T by sampling two successive gradient recalled echo images in a single shot. Several aspects of brain mapping methods based on T2*‐weighted imaging and R2* mapping were quantitatively compared. These include the detected activation volume, functional contrast (FC), signal‐to‐noise ratio (SNR), and contrast‐to‐noise ratio (CNR). Studies based on the R2* mapping method have the following potential advantages: maximum functional contrast, less dependent on TE; and reduced inflow effects. R2* mapping produced the highest functional contrast, but not the largest activation volume due to the reduced signal‐to‐noise ratio and inflow effects. The sensitivity for activation detection is significantly correlated with the contrast‐to‐noise ratio, which is determined by both the SNR and FC. Copyright © 2001 John Wiley & Sons, Ltd.

Abbreviations used:

BOLD

blood oxygen level dependent

CNR

contrast‐to‐noise ratio

FC

functional contrast

FFT

fast fourier transformation

GRE

gradient recalled echo

ROI

region of interest

SNR

Signal‐to‐noise ratio

TE

echo time.
Efficient communication in unknown networks
Authors: Gargano Luisa , Pelc Andrzej , Pérennes Stéphane , Vaccaro Ugo
Published: August 2002

We consider the problem of disseminating messages in networks. We are interested in information dissemination algorithms in which machines operate independently without any knowledge of the network topology or size. Three communication tasks of increasing difficulty are studied. In blind broadcasting (BB), the goal is to communicate the source message to all nodes. In acknowledged blind broadcasting (ABB), the goal is to achieve BB and inform the source about it. Finally, in full synchronization (FS), all nodes must simultaneously enter the state terminated after receiving the source message. The algorithms should be efficient both in terms of the time required and the communication overhead they put on the network. We limit the latter by allowing every node to send a message to at most one neighbor in each round. We show that BB is achieved in time at most 2n in any n‐node network and show networks in which time 2n − o(n) is needed. For ABB, we show algorithms working in time (2 + ϵ)n, for any fixed positive constant ϵ and sufficiently large n. Thus, for both BB and ABB, our algorithms are close to optimal. Finally, we show a simple algorithm for FS working in time 3n and a more complicated algorithm which works in time 2.9n. The optimal time of full synchronization remains an open problem. © 2001 John Wiley & Sons, Inc.