bluuebunny/crossref_metadata_2025 huggingface dataset:
The cephalic sensory organ in veliger larvae of pulmonates (Gastropoda: Mollusca)
Authors: Ruthensteiner Bernhard , Schaefer Kurt
Published: August 2002

The apical area of larvae of four primitive pulmonate species was investigated by means of serial ultrathin and light microscope sections. Cephalic sensory organs (CSOs) were found in the larvae of Onchidium cf. branchiferum (Onchidiidae) and Laemodonta octanfracta (Ellobiidae), while no trace of the organ was present in the larvae of Ovatella myosotis (Ellobiidae) or Williamia radiata (Siphonariidae). TEM investigation revealed very similar CSOs in O. cf. branchiferum and L. octanfracta, with characteristic putative sensory cell types: ampullary cells with an internal ampulla containing densely packed cilia, para‐ampullary cells with external cilia parallel to the surface, and ciliary tuft cells, bearing short ciliary tufts. The epithelium covering the organ has a thick microvillar border with microvilli laterally bearing a pair of electron‐dense accumulations and a glycocalyx with interspersed flat plaque‐like elements. While homologues of all major elements of the CSO can be found in other gastropod taxa, for example caenogastropods and opisthobranchs, the homology of the ampullary cell with similar cells in nongastropods appears unlikely. The CSO of L. octanfracta is associated with an additional structure, an epithelial external protrusion, lying ventral to the CSO. The absence of the organ in W. radiata weakens hypotheses on the organ's function of examining settlement conditions and velar control. J. Morphol. 251:93–102, 2002. © 2002 Wiley‐Liss, Inc.
Postnatal skeletal ontogeny in Callisaurus draconoides and Uta stansburiana (Iguania: Phrynosomatidae)
Authors: Maisano Jessica Anderson
Published: August 2002

The mineralization of the skeleton from hatching to near maximum size in two phrynosomatid lizards, Callisaurus draconoides and Uta stansburiana, is described in detail. Observed patterns in the appearance of epiphyseal secondary centers, ossification centers, apophyseal ossifications, and calcifications, the distribution of sesamoids, and the timing of fusions, are compared and contrasted with observations of other squamates available in the literature. Overall, Callisaurus and Uta exhibit an advanced state of ossification in the hatchling relative to other squamate neonates and share a similar sequence of braincase fusions and appearance of secondary centers. Preliminary observations suggest that patterns of postnatal skeletal development are highly conserved and independent of patterns of prenatal morphogenesis, and thus a potentially rich source of character data for systematic investigations. J. Morphol. 251:114–139, 2002. © 2002 Wiley‐Liss, Inc.
Avian furcula morphology may indicate relationships of flight requirements among birds
Authors: Hui Clifford A.
Published: August 2002

This study examined furcula (wishbone) shape relative to flight requirements. The furculae from 53 museum specimens in eight orders were measured: 1) three‐dimensional shape (SR) as indicated by the ratio of the direct distance between the synostosis interclavicularis and the ligamentous attachment of one of its clavicles to the actual length of the clavicle between those same two points, and 2) curvature within the primary plane (LR) as indicated by the ratio of the length of the clavicle to the sum of the orthogonal distances between the same points using a projected image. Canonical discriminant analysis of these ratios placed the individuals into a) one of four general flight categories and b) one of eight taxonomic orders. The four flight categories were defined as: i) soaring with no flapping, ii) flapping with no soaring, iii) subaqueous (i.e., all wingbeats taking place under water), and iv) partial subaqueous (i.e., wingbeats used for both aerial and submerged flapping). The error rate for placement of the specimens in flight categories was only 26.4%, about half of the error rate for placement in taxonomic orders (51.3%). Subaqueous fliers (penguins, great auks) have furculae that are the most V‐shaped. Partial subaqueous fliers (alcids, storm petrels) have furculae that are more U‐shaped than the subaqueous fliers but more V‐shaped than the aerial flapping fliers. The partial subaqueous fliers have furculae that are also the most anteriorly curved, possibly increasing protraction capability by changing the angle of applied force and increasing attachment area for the origin of the sternobrachialis pectoralis. The increased protraction capability can counteract profile drag, which is greater in water than in air due to the greater density of water. Soaring birds have furculae that are more U‐shaped or circular than those of flapping birds and have the smallest range of variation. These results indicate that the shape of the furcula is functionally related to general differences in flight requirements and may be used to infer relationships of these requirements among birds. J. Morphol. 251:284–293, 2002. © 2002 Wiley‐Liss, Inc.
Comparison of isometric contractile properties in hindlimb extensor muscles of the frogs Rana pipiens and Bufo marinus: Functional correlations with differences in hopping performance
Authors: Chadwell Brad A. , Hartwell Hadley J. , Peters Susan E.
Published: August 2002

The leopard frog (Rana pipiens) is an excellent jumper that can reach high take‐off velocities and accelerations. It is diurnal, using long, explosive jumps to capture prey and escape predators. The marine toad (Bufo marinus) is a cryptic, nocturnal toad, typically using short, slow hops, or sometimes walking, to patrol its feeding area. Typical of frogs with these different locomotor styles, Rana has relatively long hindlimbs and large (by mass) hindlimb extensor muscles compared to Bufo. We studied the isometric contractile properties of their extensor muscles and found differences that correlate with their different hopping performances. At the hip (semimembranosus, SM), knee (peroneus, Per) and ankle (plantaris longus, PL), we found that Rana's muscles tended to produce greater maximum isometric force relative to body mass, although the difference was significant only for PL. This suggests that differences in force capability at the ankle may be more important than at other joints to produce divergent hopping performances. Maximum isometric force scaled with body mass so that the smaller Rana has relatively larger muscles and force differences between species may reflect size differences only. In addition, Rana's muscles exhibited greater passive resistance to elongation, implying more elastic tissue is present, which may amplify force at take‐off due to elastic recoil. Rana's muscles also achieved a higher percentage of maximum force at lower stimulus inputs (frequencies and durations) than in Bufo, perhaps amplifying the differences in force available for limb extension during natural stimulation. Twitch contraction and relaxation times tended to be faster in Rana, although variation was great, so that differences were significant only for Per. Fatigability also tended to be greater in Rana muscles, although, again, values reached significance in only one muscle (PL). Thus, in addition to biomechanical effects, differences in hopping performance may also be determined by diverse physiological properties of the muscles. J. Morphol. 251:309–322, 2002. © 2002 Wiley‐Liss, Inc.
Chondrocranial development in larval Rana sylvatica (Anura: Ranidae): Morphometric analysis of cranial allometry and ontogenetic shape change
Authors: Larson Peter M.
Published: August 2002

This study provides baseline quantitative data on the morphological development of the chondrocranium in a larval anuran. Both linear and geometric morphometric methods are used to quantitatively analyze size‐related shape change in a complete developmental series of larvae of the wood frog, Rana sylvatica. The null hypothesis of isometry was rejected in all geometric morphometric and most linear morphometric analyses. Reduced major axis regressions of 11 linear chondrocranial measurements on size indicate a mixture of allometric and isometric scaling. Measurements in the otic and oral regions tend to scale with negative allometry and those associated with the palatoquadrate and muscular process scale with isometry or positive allometry. Geometric morphometric analyses, based on a set of 11 chondrocranial landmarks, include linear regression of relative warp scores and multivariate regression of partial warp scores and uniform components on log centroid size. Body size explains about one‐quarter to one‐third of the total shape variation found in the sample. Areas of regional shape transformation (e.g., palatoquadrate, otic region, trabecular horns) are identified by thin‐plate spline deformation grids and are concordant with linear morphometric results. Thus, the anuran chondrocranium is not a static structure during premetamorphic stages and allometric patterns generally follow scaling predictions for tetrapod cranial development. Potential implications regarding larval functional morphology, cranial development, and chondrocranial evolution in anurans are discussed. J. Morphol. 252:131–144, 2002. © 2002 Wiley‐Liss, Inc.
Quantification of errors in volume measurements of the caudate nucleus using magnetic resonance imaging
Authors: Gurleyik Kilichan , Haacke E. Mark
Published: August 2002

Purpose

To quantify the various sources of error in measuring the volume of the caudate nucleus and to understand these errors would lead to the standardization of the MRI protocol and would make the utility of data from around the world more viable in a global database.

Materials and Methods

We collected data at four different sites all using a Siemens 1.5T Vision MR Scanner. In all cases the same 3D gradient‐echo scans were used on a single volunteer and analyzed by a set of five observers.

Results

The errors estimated were: system calibration (a random variation of up to 1.2%), partial volume error (a bias of up to 1.5% using isotropic resolution of 1 × 1 × 1 mm3), geometric distortion (a potential bias of 1%), intra‐observer error (a random variation of up to 3%), effects of ringing (area biases of up to 7% when a zoom of 4 was used) and inter‐observer error (with a bias of usually 5– 10% but sometimes as large as 16% among our five observers). Individual mean variations from one system to another differed by less than 5% (except for two observers at one site), consistent with a maximum error of 7% coming from the area bias due to limitations in the images themselves. We also measured the effect of variable resolution on the volume estimates and found that the measured volumes were consistent over a broad range of signal‐to‐noise‐ratios (SNRs).

Conclusion

Given the observed dependence of the caudate volumes on SNR and resolution, if isotropic resolution is required because a complicated structure is being imaged, then the lower SNR suffered by collecting 1 × 1 × 1 mm3 data at 1.5T still appears to be sufficient to make accurate volume measurements as long as the contrast‐to‐noise ratio (CNR) is on the order of 4:1. Based on our results, predictions are made as to what the best approach would be to improve the data acquisition scheme to keep individual errors under 2% and biases under 3.5%. We conclude that if users can be trained to identify the structure of interest in the same way, the inter‐observer error could be reduced to that of intra‐observer day‐to‐day error. J. Magn. Reson. Imaging 2002;15:353–363. © 2002 Wiley‐Liss, Inc.
Redox buffering in an electrospray ion source using a copper capillary emitter
Authors: Van Berkel Gary J. , Kertesz Vilmos
Published: August 2002

An electrospray ion source used in electrospray mass spectrometry is a two‐electrode, controlled‐current electrochemical flow cell. Electrochemical reactions at the emitter electrode (oxidation and reduction in positive and negative ion modes respectively) provide the excess charge necessary for the quasi‐continuous production of charged droplets and ultimately gas‐phase ions with this device. We demonstrate here that a copper capillary emitter, in place of the more commonly used stainless‐steel capillary emitter, can be utilized as a redox buffer in positive ion mode. Anodic corrosion of the copper capillary during normal operation liberates copper ions to solution and in so doing maintains the interfacial potential at this electrode near the equilibrium potential for the copper corrosion process [E° = 0.34 V versus standard hydrogen electrode (SHE)]. Fixing the interfacial potential at the emitter electrode provides control over the electrochemical reactions that take place at this electrode. It is shown that the oxidation of N‐phenyl‐1,4‐phenylenediamine to N‐phenyl‐1,4‐phenylenediimine (Ep/2 = 0.48 V versus SHE) can be completely avoided using the copper emitter, whereas this analyte is completely oxidized with a stainless‐steel capillary emitter under the same conditions. Moreover, using N‐phenyl‐1,4‐phenylenediimine, we demonstrate that reduction reactions can occur at the copper emitter electrode in positive ion mode. Emitter corrosion, in addition to redox buffering, provides a convenient means to introduce metal ions into solution for analytical use in electrospray mass spectrometry. Published in 2001 by John Wiley & Sons, Ltd.
Guest‐to‐host proton transfer in melatonin–β‐cyclodextrin inclusion complex by ionspray, fast atom bombardment and tandem mass spectrometry
Authors: Bongiorno David , Ceraulo Leopoldo , Mele Andrea , Panzeri Walter , Selva Antonio , Liveri Vincenzo Turco
Published: August 2002

Ionspray (IS) and fast atom bombardment (FAB) positive ionization mass spectrometry (MS) of 1 : 1 β‐cyclodextrin (β‐CD)–melatonin (MLT) host–guest complex allowed the detection of gaseous protonated 1 : 1 β‐CD–MLT. Tandem MS collision‐induced dissociation (CID) of such protonated 1 : 1 β‐CD–MLT species showed the proton (charge) to be retained to a significant extent by the host and by its cage fragmentation products, in spite of the higher proton affinity of MLT with respect to that of β‐CD. This requires an endothermic guest‐to‐host proton transfer to occur within the gaseous association. Collisional activation could be accounted for by the promotion of such an endothermic process; however, the proton affinity decrease of the guest determined by the loss of the elements of acetamide, which is a dominant MS dissociation reaction of pure protonated MLT, could also provide a rationale for such an endothermic guest‐to‐host proton transfer. This proposal parallels the reaction scheme we had previously formulated for the analogous MS and tandem MS behaviour of 1 : 1 β‐CD–5‐methoxytryptamine inclusion complex with the protonated 5‐methoxytryptamine guest undergoing deamination. Copyright © 2001 John Wiley & Sons, Ltd.
Characterization of multimetallic grid‐type complexes by electrospray mass spectrometry
Authors: Nierengarten Hélène , Leize Emmanuelle , Breuning Esther , Garcia Ana , Romero‐Salguero Francisco , Rojo Javier , Lehn Jean‐Marie , Van Dorsselaer Alain
Published: August 2002

The self‐assembly of the terdentate ligands 1a–h, based on terpyridine‐like binding sites, with octahedrally coordinated metal ions, such as FeII, CoII, CuII, ZnII, CdII, HgII and PbII, leads to the formation of the supramolecular grid‐type complexes 2a–c(MII), 3d–g(MII) and 4h(MII). The structures and compositions of these coordination complexes in solution were deduced from electrospray mass spectrometry (ESMS) measurements. The results agree with the data available from x‐ray radiocrystallography in the solid state and/or NMR spectroscopy in solution. ESMS may be applied in cases where other methods are difficult to use or inconclusive. This study stresses the power of ESMS in supramolecular chemistry. Copyright © 2001 John Wiley & Sons, Ltd.
Parvovirus B19 nonstructural (NS1) protein as a transactivator of interleukin‐6 synthesis: Common pathway in inflammatory sequelae of human parvovirus infections?
Authors: Mitchell Leslie Ann
Published: August 2002

This review focuses on the role that human parvovirus B19 nonstructural (NS1) protein as a transactivator of the proinflammatory cytokine, interleukin‐6 (IL‐6), might play in triggering the multiparametric inflammatory outcomes of B19 infection. Parvovirus B19 is a ubiquitous virus, and it is often expressed during conditions of immunodepression including that induced by long‐term chemotherapy, viral infection (HIV, HTLV‐1), or genetic immunodeficiency disorders. Through NS1 expression, B19 may contribute to the immune dysregulation associated with these disorders, or serve as a cofactor in enhancing retroviral replication. Hence, NS1 transactivation of proinflammatory cytokine promoters such as IL‐6 may be pivotal in triggering the various inflammatory and autoimmune disorders that have been linked to parvovirus B19 infections. J. Med. Virol. 67:267–274, 2002. © 2002 Wiley‐Liss, Inc.
Cross code comparison between NEC 4 and transmission line matrix (TLM) methods for whole ship modelling
Authors: Kazik John J.
Published: August 2002

This paper describes the application of transmission line matrix methods (TLM) as a possible alternative technique to NEC for the modelling of the electromagnetic environment found on board typical ship topsides. It presents the results of an initial feasibility study demonstrating that TLM can produce similar results to an equivalent NEC model. It then demonstrates the results of an initial and refined ship model, where TLM required a single day for the same frequency range and output as the equivalent NEC model, requiring more than 15 days.

The paper presents initial results comparing antenna impedance and radiation patterns as determined by both methods. The paper also demonstrates the capability of the TLM technique to assess complex objects with only the power of a typical commercially available desktop PC. © Crown copyright 2001. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
Cyclic AMP differentiation of the oligodendroglial cell line N20.1 switches staurosporine‐induced cell death from necrosis to apoptosis
Authors: Studzinski Diane M. , Benjamins Joyce A.
Published: August 2002

Understanding the regulation of cell death pathways is critical for protecting myelin‐producing cells and their associated axons during injury resulting from multiple sclerosis and other degenerative diseases. The immortalized N20.1 oligodendroglial cell line provides a useful model for identifying mechanisms that can be exploited to attenuate cell death in myelin‐producing cells and their precursors. In our hands, the N20.1 cell line exhibits different characteristics and morphology depending on temperature (permissive or non‐permissive) and the presence of cAMP‐elevating agents (Studzinski et al. [1998] Neurochem. Res. 23:435–441; Boullerne et al. [1999] J. Neurochem. 72:1050–1060; Studzinski et al. [1999] J. Neurosci. Res. 57:633–642). Our laboratory previously observed that NO donors cause primarily necrotic death in N20.1 cells grown at permissive temperature, but the NO donor SNP switched a portion of cell death to the apoptic pathway. We have continued our study of apoptotic death in these cells by comparing the effects of staurosporine, a known apoptotic agent, on cells grown at the permissive temperature (“undifferentiated”) vs. the non‐permissive temperature in the presence of forskolin (“differentiated”). Undifferentiated N20.1 cells exhibit maximal cell death after 24 hr of exposure to 50 nM staurosporine, whereas differentiated cells show delayed cell death, with maximal death seen after 48 hr. Pyknotic nuclei were observed in both growth conditions; however, differentiated cells were protected by caspase inhibitors, whereas undifferentiated cells were not. Increased ssDNA staining and DNA laddering were found following 24‐hr staurosporine treatment in the differentiated cells only. These results support the conclusion that N20.1 cells can switch from necrotic to apoptotic cell death when cell division is slowed and cyclic AMP is elevated. J. Neurosci. Res. 66:691–697, 2001. © 2001 Wiley‐Liss, Inc.
Mitochondrial polarization in rat hippocampal astrocytes is resistant to cytosolic Ca2+ loads
Authors: Kahlert Stefan , Schild Lorenz , Reiser Georg
Published: August 2002

The influence of physiological Ca2+‐inducing stimuli and agents mimicking ischemic conditions on mitochondrial potential was studied in postnatal (P1) hippocampal astrocytes. Cytosolic Ca2+ loads with characteristic kinetics of rise and duration, detected by Fura‐2, were provoked by extracellular Ca2+ influx, release from InsP3‐sensitive intracellular stores, or inhibition of the reloading of endoplasmic reticulum Ca2+ stores. Inhibitors of mitochondrial respiration caused only moderate release of Ca2+ from intracellular stores, inducing a rise of less than 60 nM. The maximal Ca2+ rise was found with InsP3‐mediated responses (500 nM; via ATP) or with ionophore (4‐Br‐A23187)‐mediated Ca2+ influx from extracellular medium (770 nM). Remarkably, all these agents causing significant rise of cytosolic Ca2+, only minimally depolarized the mitochondria. Membrane potential of mitochondria was monitored by Rh123 or TMRE. Depolarization was only found with very high cytosolic Ca2+ levels (above 60 μM; measured by fura FF). These were achieved with external Ca2+ influx by ionophore in combination with inhibition of glycolysis. Thus, mitochondria in the astrocytes are obviously not sensitive to moderate cytosolic Ca2+ loads, irrespective of the source of Ca2+. Furthermore, isolated rat brain mitochondria display a low sensitivity of respiratory activity to Ca2+, which is consistent with the data obtained with the astrocytes in vitro. The capacity of isolated mitochondria to build up a potential was gradually reduced at low micromolar Ca2+ and totally compromised only at Ca2+ concentrations in the 100 μM range. © 2001 Wiley‐Liss, Inc.
Dual mechanisms of Ca2+ increases elicited by N‐methyl‐D‐aspartate in immature and mature cultured cortical neurons
Authors: Nakamichi Noritaka , Ohno Hiroshi , Kuramoto Nobuyuki , Yoneda Yukio
Published: August 2002

Cortical primary cultures were loaded with the fluorescent indicator fluo‐3 for assessment of intracellular‐free Ca2+ ions with the aid of a confocal laser‐scanning microscope. The addition of N‐methyl‐D‐aspartic acid (NMDA) markedly increased the number of fluorescent cells in a manner sensitive to prevention by both an NMDA channel blocker and MgCl2. In the absence of added MgCl2, NMDA induced a sustained increase in the number of fluorescent cells with a transient increase by KCl in cells cultured for 3 days in vitro (DIV). Both nifedipine and dantrolene were more potent in preventing the increase by NMDA in cortical preparations cultured for 9 DIV than those for 3 DIV. These results suggest that activation of NMDA receptors may lead to a sustained increase in intracellular‐free Ca2+ concentrations in immature cultured neurons, in a manner less dependent on the influx through L‐type voltage‐dependent channels as well as the release from intracellular stores than in mature neurons. © 2001 Wiley‐Liss, Inc.
Modulation of 5‐HT system in mice with a targeted disruption of neuromedin B receptor
Authors: Yamano Mariko , Ogura Hiroo , Okuyama Shigeru , Ohki‐Hamazaki Hiroko
Published: August 2002

To assess the role of neuromedin B receptor (NMB‐R) on the modulation of serotonergic (5‐HT) system, the function of the 5‐HT system was examined in mice lacking the NMB‐R gene. Immunohistochemical analysis of brain sections revealed that 5‐HT expression level in the dorsal raphe neurons was elevated in NMB‐R‐deficient mice compared with wild‐type mice. Although restraint stress enhanced 5‐HT expression in these neurons in wild‐type mice, this treatment did not affect 5‐HT expression level in NMB‐R‐deficient mice, indicating the modulation of 5‐HT system in the mutant mice. Since 5‐HT system is involved in responses to stress and anxiety, we characterized stress response in these mice. The number of c‐Fos expressing cells in the paraventricular nucleus of the hypothalamus was higher in NMB‐R‐deficient mice than in wild‐type mice in both basal and stressed conditions. Moreover, the plasma corticosterone level under restraint stress was elevated in NMB‐R‐deficient mice compared to wild‐type mice. In the forced swimming tests, the duration of immobility was longer in mutant mice than in wild‐type mice. These data show dysregulated response to stress in NMB‐R‐deficient mice. However, behavior related to anxiety, assessed by elevated plus‐maze and light‐dark box, was not affected in NMB‐R‐deficient mice. NMB‐R is known to be expressed in dorsal raphe neurons, and our data suggest that NMB‐R has an important role in fine tuning of subsets of 5‐HT neurons in this nucleus, and impairment of this system leads to the dysregulated response to stress. © 2002 Wiley‐Liss, Inc.
Climate change in the Colorado Rocky Mountains: free air versus surface temperature trends
Authors: Pepin N. , Losleben M.
Published: August 2002

A high elevation data set of surface temperatures from the Front Range of the Rocky Mountains in Colorado, USA, is analysed for evidence of long‐term change (1952–98). Sites range from the high plains of Colorado (1509 m) to the alpine tundra (3749 m). Systematic changes in surface‐based lapse rates are uncovered, with absolute cooling at the highest elevations, but little temperature change on the high plains. There is lapse‐rate steepening at the higher elevations (>3000 m). A synoptic analysis using gridded pressure data shows lapse rate changes to be largely independent of synoptic type. Radiosonde ascents from Denver (1956–98) and Grand Junction (1946–98) are used to derive air equivalent temperatures (AETs) at the same elevations as the surface records. AETs show a contrasting temporal trend, with absolute warming at all levels. Furthermore, free‐air lapse rates are weakening at higher elevations, the warming becoming stronger with height. A comparison of the two data sets through derivation of free‐air–surface temperature differences shows that the alpine tundra zone of the high Rockies is becoming a progressively stronger heat sink. Possible explanations include increased snow cover, enhanced air movement over the surface and decreased solar radiation input. The heat sink enhancement has led to rapid cooling in the alpine tundra that could not be predicted from the free‐air record, casting doubt upon the strong dependence on free‐air temperature changes in climate modelling when investigating the potential effects of global warming in mountainous regions. In addition, these local surface trends are of the opposite sign to global and other regional trends identified in many recent observational and modelling studies. Copyright © 2002 Royal Meteorological Society.
Hard‐to‐cook tendency of chickpea (Cicer arietinum L) varieties
Authors: Reyes‐Moreno C , Rouzaud‐Sandez O , Milán‐Carrillo J , Garzón‐Tiznado J A , Camacho‐Hernández L
Published: August 2002

Chickpeas (Cicer arietinum L) develop the hard‐to‐cook (HTC) defect during storage at high temperatures (>25 °C) and high relative humidities (RH>65%). The objective of this work was to assess the tendency of chickpea varieties to become HTC. Three samples of chickpeas (Surutato 77, Mocorito 88 and Blanco Sinaloa 92) were grown under irrigation conditions. Two hardening procedures were used: (1) storage hardening—samples were stored at 33–35 °C and 76% relative humidity for 160 days; (2) chemical hardening—materials were soaked in 0.1 M acetate buffer (pH 4.0) at 37 °C for 1–7 h. The cooking time curves generated by chemical hardening had shapes similar to those obtained by storage hardening; both procedures were equally capable of discriminating chickpea varieties based on their susceptibility to develop the HTC condition. Chemical hardening might be useful for screening new chickpea varieties; its advantage over the storage method is its rapidity.

© 2001 Society of Chemical Industry
Aflatoxins, ochratoxin A and zearalenone in Brazilian corn cultivars
Authors: Machinski Miguel , Valente Soares Lucia M , Sawazaki Eduardo , Bolonhezi Denizart , Castro Jairo L , Bortolleto Nelson
Published: August 2002

Past surveys indicated that the occurrence of aflatoxins, zearalenone and ochratoxin A was not a problem in corn and corn products in the state of São Paulo, Brazil. However, according to recent studies, a change in pattern has been detected. To obtain a better overview, these toxins were searched for in 110 samples of freshly harvested corn, corresponding to 48 commercial cultivars planted at three different locations in the state. Aflatoxin contamination was found in 60 (54.5%) of the samples, in levels ranging from 6 to 1600 µg kg−1 aflatoxin B1. Insect control was exercised, so this was not the main route of corn infection. Endosperm type, germplasm type, number of days to flowering, and length of time the mature corn remained in the field had no effect on aflatoxin contamination. Ochratoxin A was found in two samples (206 and 128 µg kg−1) and zearalenone in one sample (4640 µg kg−1). Possible causes of the increase in aflatoxin levels may lie in the changing nature of the commercial cultivars employed, associated with the forsaking of the original landraces, and in a change in the toxigenicity pattern of the corn mycoflora Aspergillus flavus/Aspergillus parasiticus prevailing strains.

© 2001 Society of Chemical Industry
Preparation of flavanol‐rich green tea extract by precipitation with AlCl3
Authors: Chen Zhen‐Yu , Wang Shu , Lee Kwong Man Simon , Huang Yu , Ho Walter K K
Published: August 2002

The aim of this study was to use AlCl3 in the extraction of green tea flavanols (GTFs) from longjing green tea and examine the factors that influence the yield of GTF extract. Dry tea leaves were soaked in hot distilled water and the infusion was obtained by filtration. To the tea infusion, varying amounts of AlCl3 were added, causing precipitation of GTFs. After adjusting the pH to 4.0–6.5 and centrifugation, the yellow precipitate was collected. Sulphuric acid solution (40%) was then used to dissolve the GTFs from the yellow precipitate. The GTF solution was extracted using an equal volume of ethyl acetate. After the removal of ethyl acetate using a rotary evaporator, the GTF extract was redissolved in distilled water and the whole process was repeated. The resulting GTF extract was freeze‐dried. It was found that the amount of AlCl3 used and the pH and temperature of the precipitation mixture significantly affected the yield and purity of GTF extract. A yield of 9.6 g extract per 100 g dry tea leaves with GTFs > 94% could be obtained if AlCl3 was used in the ratio of 15 g per 100 g equivalent dry tea leaves and the pH of the precipitation mixture was adjusted to 5.5 at 30 °C.

© 2001 Society of Chemical Industry
A political approach to relationship marketing: case study of the Storsjöyran festival
Authors: Larson Mia
Published: August 2002

This study is concerned with interorganisational aspects of relationship marketing, which, in turn, has led to a focus on political aspects, i.e. on interests, conflicts and power in a project network consisting of actors marketing a festival. A metaphor of a project network, the political market square (PSQ), is introduced and used in the analysis of a case study of the Storsjöyran Festival in Sweden. In order to understand the politics and the dynamics in the PSQ, actors' access is discussed. Moreover, interactions between actors, which are to be regarded as cooperative or characterised by power games, and the degree of change dynamics, contribute to understanding dynamic political processes. Identified political processes were gatekeeping, negotiations, coalition building, building of trust and identify building. These processes, and actors' entries and exits between the PSQ and a wider network, caused turbulence and changed the power structure of the PSQ. The turbulence fostered change and innovations that resulted in product development. However, actors' shared identities and a stable, positive image of the festival moderated the turbulence. Copyright © 2002 John Wiley & Sons, Ltd.
UV absorption spectra of HO2, CH3O2, C2H5O2, and CH3C(O)CH2O2 radicals and mechanism of the reactions of F and Cl atoms with CH3C(O)CH3
Authors: Nielsen Ole J. , Johnson Matthew S. , Wallington Timothy J. , Christensen Lene K. , Platz Jesper
Published: August 2002

Pulse radiolysis techniques were used to measure the gas phase UV absorption spectra of the title peroxy radicals over the range 215–340 nm. By scaling to σ(CH3O2)240 nm = (4.24 ± 0.27) × 10−18, the following absorption cross sections were determined: σ(HO2)240 nm = 1.29 ± 0.16, σ(C2H5O2)240 nm = 4.71 ± 0.45, σ(CH3C(O)CH2O2)240 nm = 2.03 ± 0.22, σ(CH3C(O)CH2O2)230 nm = 2.94 ± 0.29, and σ(CH3C(O)CH2O2)310 nm = 1.31 ± 0.15 (base e, units of 10−18 cm2 molecule−1). To support the UV measurements, FTIR‐smog chamber techniques were employed to investigate the reaction of F and Cl atoms with acetone. The F atom reaction proceeds via two channels: the major channel (92% ± 3%) gives CH3C(O)CH2 radicals and HF, while the minor channel (8% ± 1%) gives CH3 radicals and CH3C(O)F. The majority (>97%) of the Cl atom reaction proceeds via H atom abstraction to give CH3C(O)CH2 radicals. The results are discussed with respect to the literature data concerning the UV absorption spectra of CH3C(O)CH2O2 and other peroxy radicals. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 34: 283–291, 2002
Building landscapes: village development in Zimbabwe
Authors: Moyo S.
Published: August 2002

This paper argues that there is a need to fill a specific empirical and conceptual gap in land policy analysis in Zimbabwe. This ‘gap’ has arisen from the predominantly macro level economic theoretical perspectives on the land question, and from an inadequate conceptualization of the local level character of the land debate in Zimbabwe. The purpose of this paper is to stress the importance of focusing on the land question from the standpoint of the peasant householders in the Communal Areas (CAs). These issues are raised through the examination of land use and land‐use history in Mhezi Ward in Makoni District, Zimbabwe. This paper does not comment on the recent political moves to redistribute 1471 Large Scale Commercial Farms (LSCF) as this process must be discussed in another debate. Copyright © 2001 John Wiley & Sons, Ltd.
Photomechanical transdermal delivery of insulin in vivo
Authors: Lee Shun , McAuliffe Daniel J. , Mulholland Stephen E. , Doukas Apostolos G.
Published: August 2002

Background and Objective

Previous studies have shown that photomechanical waves transiently permeabilize the stratum corneum in vivo. The aim of the present work was to investigate the potential of photomechanical waves for systemic drug delivery.

Study Design/Materials and Methods

Photomechanical waves were generated by ablation of a polystyrene target by a Q‐switched ruby laser. Systemic insulin delivery in a streptozotocin‐diabetic rat model was monitored by measuring the blood glucose level.

Results

After photomechanical insulin delivery, the blood glucose decreased 80  ±  3% and remained below 200 mg/dl for more than 3 hours. Whereas in control experiments (for which insulin was applied without photomechanical waves), there was no dramatic change in the blood glucose (standard deviation of measurements over 4 hours was 7%).

Conclusion

The application of the photomechanical waves allowed ∼6‐kDa protein molecules (insulin) to pass through the stratum corneum and into the systemic circulation. Lasers Surg. Med. 28:282–285, 2001. © 2001 Wiley‐Liss, Inc.
Use of osmotically active agents to alter optical properties of tissue: Effects on the detected fluorescence signal measured through skin
Authors: Vargas Gracie , Chan Kin F. , Thomsen Sharon L. , Welch A.J.
Published: August 2002

Background and Objective

Hyper‐osmotic chemical agents were used to study the effects of transient tissue scattering on the remitted fluorescence emission intensity from a target placed under a tissue sample.

Study Design/Materials and Methods

A fluorescent film was placed underneath in vitro and in vivo samples of hamster skin, and the remitted fluorescent signal traveling to the tissue surface was monitored over time as the tissue was treated with an osmotically active agent.

Results

The detected fluorescent signal increased as the scattering in tissue samples was substantially reduced. The increase was greater for dimethyl sulfoxide than glucose or glycerol. It was not statistically different between in vivo skin and in vitro skin.

Conclusions

The study shows how chemical agents can be used to improve the detected signal for a specific optical application. It could be useful in a number of optical therapeutic and diagnostic applications that can benefit from an increase in the penetration depth of light. Lasers Surg. Med. 29:213–220, 2001. © 2001 Wiley‐Liss, Inc.
Sequential changes in hepatocarcinogenesis induced by diethylnitrosamine plus thioacetamide in Fischer 344 rats: Induction of gankyrin expression in liver fibrosis, pRB degradation in cirrhosis, and methylation of p16INK4A exon 1 in hepatocellular carcinoma
Authors: Park Tae Jun , Kim Hong Seok , Byun Kyu Hee , Jang Ja June , Lee Yun Sil , Lim In Kyoung
Published: August 2002

To clarify the sequential changes in pRB and p16 during different stages of hepatocarcinogenesis such as fibrosis, cirrhosis, hepatocellular adenoma (HCA), and hepatocellular carcinoma (HCC), male Fischer 344 rats were singly injected with diethylnitrosamine (DEN), immediately followed with phenobarbital for 1 wk and then thioacetamide (TAA) for 39 wk in drinking water. Rats were killed at 9, 20, 30, and 40 wk after DEN initiation and changes of pRB level, p16 gene hypermethylation, and in vivo gankyrin expression were examined. Histologic examination showed stepwise appearances of fibrosis, cirrhosis, HCA, and HCC at weeks 9, 20, 30, and 40, respectively. Hypermethylation of p16 exon 1 was not found until HCA but appeared in 50% of the rats with HCC accompanied by complete loss of its mRNA expression. The amount of glutathione S‐transferase–gankyrin bound to pRB and pRB degradation in the liver depended on the concentration of gankyrin and incubation time. Gankyrin expression preceded pRB degradation in liver cirrhosis. In conclusion, gankyrin expression induced in liver fibrosis accelerated the degradation of pRB during liver cirrhosis, and inactivation of p16 exon 1 by DNA hypermethylation occurred during the progression of tumor cells to poorly differentiated HCC. Inactivation of pRB and/or p16 resulted in complete loss of regulation in the cell‐division cycle during early and late stages, respectively, of hepatocarcinogenesis. Mol. Carcinog. 30:138–150, 2001. © 2001 Wiley‐Liss, Inc.
Involvement of the medial pallidum in focal myoclonic dystonia: A clinical and neurophysiological case study
Authors: Liu Xuguang , Griffin Ivan C. , Parkin Simon G. , Miall R. Christopher , Rowe Jeremy G. , Gregory Ralph P. , Scott Richard B. , Aziz Tipu Z. , Stein John F.
Published: August 2002

We successfully treated a patient with familial myoclonic dystonia (FMD), which primarily affected his neck muscles, with bilateral deep brain stimulation (DBS) to the medial pallidum, and investigated the role of the medial pallidum in FMD. A patient with FMD underwent bilateral implantation of DBS electrodes during which field potentials (FPs) in the medial pallidum and electromyograms (EMGs) from the affected neck muscles were recorded. The effects of high‐frequency DBS to the medial pallidum on the FMD were also assessed by recording EMGs during and immediately after implantation, as well as 6 days and 8 weeks postoperatively. During spontaneous myoclonic episodes, increased FPs oscillating at 4 and 8 Hz were recorded from the medial pallidum; these correlated strongly with phasic EMG activity at the same frequencies in the contralateral affected muscles. The EMG activity was suppressed by stimulating the contralateral medial pallidum at 100 Hz during the operation and continuous bilateral DBS from an implanted stimulator abolished myoclonic activity even more effectively postoperatively. The phasic pallidal activity correlated with and led the myoclonic muscle activity, and the myoclonus was suppressed by bilateral pallidal DBS, suggesting that the medial pallidum was involved in the generation of the myoclonic activity. High‐frequency DBS may suppress the myoclonus by desynchronising abnormal pallidal oscillations. This case study has significant clinical implications, because at present, there is no effective treatment for focal myoclonic dystonia. © 2002 Movement Disorder Society.
Assessing state parity legislation
Authors: Zuvekas Samuel H.
Published: August 2002

The temptation is great, but premature, to conclude from the Sturm study that parity mandates had no effect on access and insurance coverage for the mentally ill. The study lacks statistical power for those directly covered by the mandates, and it is unlikely adequate power exists for those only indirectly affected. The inclusion of the uninsured, Medicaid enrollees, and privately covered individuals not subject to the mandates, and the imprecise outcome measures, increase the likelihood that other factors dominate parity. The timing of implementation in some states is also problematic. But Sturm asks the right questions and future waves of the Healthcare for Communities survey and other data will be better able to address them. Copyright © 2000 John Wiley & Sons, Ltd.
The effect of a penalty term involving higher order derivatives on the distribution of phases in an elastic medium with a two‐well elastic potential
Authors: Bildhauer M. , Fuchs M. , Osmolovskii V. G.
Published: August 2002

We consider the problem of minimizing

0
0, among functions u:ℝd⊃Ω→ℝd, u∣∂Ω=0, and measurable characteristic functions χ:Ω→ℝ. Here ƒ+h, ƒ−, denote quadratic potentials defined on the space of all symmetric d×d matrices, h is the minimum energy of ƒ+h and ε(u) denotes the symmetric gradient of the displacement field. An equilibrium state û, χˆ, of I [·,·,h, σ] is termed one‐phase if χˆ≡0 or χˆ≡1, two‐phase otherwise. We investigate the way in which the distribution of phases is affected by the choice of the parameters h and σ. Copyright 2002 John Wiley & Sons, Ltd.
Analysis of nonlinear effects in subcarrier‐multiplexed fiber‐optic links for CDMA RF signal transmissions
Authors: Yu Jintae , Kim Yongbum , Lee Myungmoon , Lee Kilsung , Park Jinwoo
Published: August 2002

In this letter, we propose an analytic model for performance analyses of the optical subcarrier‐multiplexing (SCM) fiber‐optic link for CDMA RF signal transmission in mobile communication networks. We present optimal operational conditions, taking account of the nonlinear effects of the optical transmission link, and the multiple‐access interference produced at the wireless environment. It is shown through BER analyses in this letter that the selection of an optical modulation index (OMI) of the SCM fiber‐optic links can be found optimally to minimize the fiber‐optic noises and intermodulation distortion due to a laser diode (LD). © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 37–40, 2001.
The CGFFT method with a discontinuous FFT algorithm
Authors: Fan Guo‐Xin , Liu Qing Huo
Published: August 2002

In the conjugate gradient–fast Fourier transform (CGFFT) method, the FFT is used to evaluate the convolution integrals. When the function to be transformed has discontinuities, the accuracy of the FFT results, and thus the CGFFT results, will degrade. In this letter, an efficient FFT algorithm is developed for discontinuous functions with both uniform and nonuniform sampled data, with O(Np+N log N) complexity, where N is the number of sampling points and p is the interpolation order. The algorithm is incorporated into the CGFFT method. Numerical results for slabs demonstrate the efficiency and accuracy of the new FFT and CGFFT algorithms. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 47–49, 2001.
Multicentre analysis of anthracycline‐induced cardiotoxicity in children following treatment according to the nephroblastoma studies SIOP No.9/GPOH and SIOP 93‐01/GPOH*
Authors: Marx M. , Langer T. , Graf N. , Hausdorf G. , Stöhr W. , Ludwig R. , Beck J.D.
Published: August 2002

Background

To study cardiac function and the incidence of anthracycline‐induced cardiotoxicity in children following treatment according to the nephroblastoma studies SIOP No.9/GPOH and SIOP 93‐01/GPOH.

Procedure

Analysis of clinical status, echocardiography, and ECG findings prior to administration of anthracyclines (median cumulative doxorubicin dose: 250 mg/m2 [range: 90–411 mg/m2] and after a median posttherapeutic interval of 2.9 years [range: 0–10.2 years]. Data on cardiac function before and/or after therapy could be obtained of 186 patients.

Results

Posttherapy left ventricular fractional shortening was reduced in 4/157 (2.5%) patients. Out of the 4 children, 2 had clinically reduced tolerance to exercise and received anticongestive therapy. Abnormal ECG findings that were not detectable prior to therapy were found in 7/124 (5.6%) children.

Conclusions

The incidence of abnormal findings is low in our study group in comparison to data from the literature and might be due to the comparably short posttherapeutic interval. Med Pediatr Oncol 2002;39:18–24. © 2002 Wiley‐Liss, Inc.
Prognostic significance of p80 and visceral involvement in childhood CD30 anaplastic large cell lymphoma (ALCL)
Authors: Massimino M. , Spreafico F. , Luksch R. , Giardini R.
Published: August 2002

Background

Between 1976 and 1998, CD30+anaplastic large cell lymphoma (ALCL) was diagnosed in 44 children (28 males, 16 females, age range 2.7–16.1 years, median 10). Up to 1993, 32 such children were treated according to a common chemotherapeutic protocol that stratified patients according to stage, without considering presenting features. Thereafter, patients presenting with visceral (lung, spleen, liver, gastro‐intestinal tract) or mediastinal involvement were assigned to a high‐risk treatment protocol with induction intensification. The generation of these two risk‐groups was the result of a retrospective analysis of clinical risk factors for therapy failure as previously reported [Massimino M, Gasparini M, Giardini R, Ann Oncol 1995;6:915–920]. Considering the whole cohort of patients divided into group A—21/22 evaluable patients with visceral/mediastinal involvement, and group B—22 evaluable patients, with other ALCL location—disease‐free survival (DFS) and survival (S) at 5 years were 57 and 58% for group A, and 83 and 100% (94% at 6 years) for group B, respectively.

Procedure

We tested 15/21 cases of group A, and 18/22 of group B for p80 immunoreactivity in order to investigate a possible correlation between ALCL locations and NPM‐ALK expression.

Results

Thirteen of 15 specimens in group A and 17/18 in group B were positive for p80.

Conclusions

It is impossible to conclude anything about p80 positivity based on a series of 33/44 patients with childhood ALCL, neither about over‐all prognosis nor about the role of visceral involvement. In adults, NPM‐ALK protein expression is a favourable prognostic factor. Med Pediatr Oncol 2001;37:97–102. © 2001 Wiley‐Liss, Inc.
1H and 13C chemical shifts for acridines: Part XVII. (1,3‐Benzothiazol‐2‐yl)amino‐9(10H)‐acridinone derivatives
Authors: Avellaneda A. , Robin M. , Faure R. , Périchaud A. , Galy J.‐P.
Published: August 2002

The 1H and 13C NMR resonances for 16 acridin‐9(10H)‐ones substituted with amino or (1,3‐benzothiazol‐2‐yl)amino groups were completely and unequivocally assigned by the concerted application of gs‐COSY, gs‐HMQC and gs‐HMBC experiments. Evidence for hydrogen bond and amino–imino tautomerism is presented for 1‐ and 4‐substituted acridin‐9(10H)‐ones. Copyright © 2002 John Wiley & Sons, Ltd.