bluuebunny/crossref_metadata_2025 huggingface dataset:
Continuous ambient‐vibration monitoring of the arch dam of Mauvoisin
Authors: Darbre Georges R. , Proulx Jean
Published: September 2002

This paper presents the experimental programme and results of a continuous ambient vibrations recording programme carried out on the 250 m arch dam of Mauvoisin. This project follows a series of previous measurements completed for seven different water levels. An automated system was set up on the dam and the ambient vibrations were recorded twice daily for a period of 6 months. Frequency shifts were tracked throughout the testing period and the effects of the varying water level were identified. The results confirmed the behaviour observed in previous ambient‐ and forced‐vibration tests. The added‐mass effects are overcome by the stiffening of the dam due to increasing hydrostatic pressure for lower reservoir levels. This trend is then reversed for higher water levels. Any temperature‐related effects were not identified. The experimental techniques are briefly described and the frequency identification process and its limitations are discussed. Copyright © 2001 John Wiley & Sons, Ltd.
Defence styles and other risk factors for eating disorders among female adolescents: a case–control study
Authors: Poikolainen Kari , Kanerva Riitta , Marttunen Mauri , Lönnqvist Jouko
Published: September 2002

Immature defence style cluster has earlier been found to be a risk factor for eating disorders but the role of individual defence styles in the aetiology of these disorders has remained unknown. In a case–control design, 57 incident, consecutive female eating disorder patients aged 14–22 years were compared with 337 female control subjects, drawn from the general population and matched for age and hospital catchment area. Eating disorder patients had higher scores of sublimation, undoing, and passive aggression, and lower scores of displacement and splitting than controls. Patients with eating disorder differ significantly from controls in the use of specific defence styles. Copyright © 2001 John Wiley & Sons, Ltd and Eating Disorders Association.
A sediment transport equation for interrill overland flow on rough surfaces
Authors: Abrahams Athol D. , Li Gary , Krishnan Chitra , Atkinson Joseph F.
Published: September 2002

A model for predicting the sediment transport capacity of turbulent interrill flow on rough surfaces is developed from 1295 flume experiments with flow depths ranging from 3·4 to 43·4 mm, flow velocities from 0·09 to 0·65 m s−1, Reynolds numbers from 5000 to 26 949, Froude numbers from 0·23 to 2·93, bed slopes from 2·7° to 10°, sediment diameters from 0·098 to 1·16 mm, volumetric sediment concentrations from 0·002 to 0·304, roughness concentrations from 0 to 0·57, roughness diameters from 1·0 to 91·3 mm, rainfall intensities from 0 to 159 mm h−1, flow densities from 1002 to 1501 kg m−3, and flow kinematic viscosities from 0·913 to 2·556 × 10−6 m2 s−1. Stones, cylinders and miniature ornamental trees are used as roughness elements. Given the diverse shapes, sizes and concentrations of these elements, the transport model is likely to apply to a wide range of ground surface morphologies.

Using dimensional analysis, a total‐load transport equation is developed for open‐channel flows, and this equation is shown to apply to interrill flows both with and without rainfall. The equation indicates that the dimensionless sediment transport rate ϕ is a function of, and therefore can be predicted by, the dimensionless shear stress θ, its critical value θc, the resistance coefficient u/u*, the inertial settling velocity of the sediment wi, the roughness concentration Cr, and the roughness diameter Dr. The model has the form

where $a = -0{\cdot}42 \ C_{\rm r}/D_{\rm r}^{0{\cdot}20}$ and $c = 1 + 0{\cdot}42 \ C_{\rm r}/D_{\rm r}^{0{\cdot}20}$. Testing reveals that the model gives good unbiased predictions of ϕ in flows with sediment concentrations less than 0·20. Flows with higher concentrations appear to be hyperconcentrated and to have sediment transport rates higher than those predicted by the model. Copyright © 2001 John Wiley & Sons, Ltd.
Improved chemometric strategies for quantitative FTIR spectral analysis and applications in atmospheric open‐path monitoring
Authors: Heise H. Michael , Müller Uwe , Gärtner Andrea G. , Hölscher Norbert
Published: September 2002

FTIR spectroscopy has been established for the monitoring of diffuse emissions into the open atmosphere. The method of choice for the evaluation of the atmospheric spectra uses the fitting of reference spectra by classical least squares. Important refinements can be achieved by selecting the optimal wavelength ranges based on objective mathematical criteria, improved spectral background strategies, and high‐quality reference spectra that allow for the adaptation of nonlinearity effects. Under these improved conditions, new detection limits for atmospheric trace components are presented. The chemometric tools developed were integrated into an expert system, affording the evaluation of the atmospheric spectra with a minimum of user interaction. Results from several field campaign measurements within a municipal waste‐treatment plant are presented, illustrating the reliability of the methods applied. Furthermore, extensive trace‐gas concentration data were collected simultaneously with two FTIR spectrometer systems under various meteorological conditions and spatial scenarios for dispersion modeling of diffuse emissions from different sites. Emission rates of ammonia area sources were determined from path‐integrated spectroscopic remote measurements and inverse dispersion modeling based on Lagrangian model calculations. The results were obtained within a factor of 1.4 times the actual emission rate values. © 2001 John Wiley & Sons, Inc. Field Analyt Chem Technol 5: 13–28, 2001
On a Mean—Generalized Semivariance Approach to Determining the Hedge Ratio
Authors: Chen Sheng‐Syan , Lee Cheng‐Few , Shrestha Keshab
Published: September 2002

A new mean‐risk hedge ratio based on the concept of generalized semivariance (GSV) is proposed. The proposed mean‐GSV (M‐GSV) hedge ratio is consistent with the GSV‐based risk–return model developed by Fishburn (1977), Bawa (1975, 1978), and Harlow and Rao (1989). The M‐GSV hedge ratio can also be considered an extension of the GSV‐minimizing hedge ratio considered by De Jong, De Roon, and Veld (1997) and Lien and Tse (1998, 2000). The M‐GSV hedge ratio is estimated for Standard & Poor's (S&P) 500 futures and compared to six other widely used hedge ratios. Because all the hedge ratios considered are known to converge to the minimum‐variance (Johnson) hedge ratio under joint normality and martingale conditions, tests for normality and martingale conditions are carried out. The empirical results indicate that the joint normality and martingale hypotheses do not hold for the S&P 500 futures. The M‐GSV hedge ratio varies less than the GSV hedge ratio for low and relevant levels of risk aversion. Furthermore, the M‐GSV hedge ratio converges to a value different from the values of the other hedge ratios for higher values of risk aversion. © 2001 John Wiley & Sons, Inc. Jrl Fut Mark 21: 581–598, 2001
Endothelin downregulates the glutamate transporter GLAST in cAMP‐differentiated astrocytes in vitro
Authors: Matsuura Sigeru , Ikegaya Yuji , Yamada Maki K. , Nishiyama Nobuyoshi , Matsuki Norio
Published: September 2002

Endothelin (ET) is a putative pathogenetic mediator associated with brain trauma and ischemia. Because a link between neuronal damage after these injuries and glial Na+‐dependent L‐glutamate transporter activity has been suggested, we investigated the effect of ET on the glutamate clearance ability of astrocytes. Dibutyryl cyclic adenosine monophosphate (dBcAMP), which is widely used to induce differentiation of cultured astrocytes, markedly increased [3H]glutamate transport activity in a concentration‐ and time‐dependent manner. In the presence of ET, however, dBcAMP decreased the glutamate uptake. This effect was efficiently prevented by an antagonist of ETB receptor, but not of ETA receptor. ET per se was virtually ineffective. Eadie–Hofstee analysis demonstrated that dBcAMP increased the Vmax value of glutamate uptake activity by 43.4% in the absence of ET, but decreased it by 41.4% in the presence of ET, without apparent changes in the Km value. Accordingly, Western blot analysis indicated that the change in transport activity correlated closely with that in expression level of the glial glutamate transporter GLAST. These results may represent the mechanisms by which ET aggravates trauma‐ and ischemia‐elicited neuronal damage. GLIA 37:178–182, 2002. © 2002 Wiley‐Liss, Inc.
Electrophysiological properties of rat retinal Müller (glial) cells in postnatally developing and in pathologically altered retinae
Authors: Felmy Felix , Pannicke Thomas , Richt Jürgen A. , Reichenbach Andreas , Guenther Elke
Published: September 2002

Retinal glial Müller cells are characterized by dominant K+ conductances. The cells may undergo changes of their membrane currents during ontogeny and gliosis as described in rabbit and man. Although the rat retina is often used in physiological experiments, the electrophysiology of rat Müller cells is less well studied. The aim of the present study was to characterize their membrane currents in postnatal development and in two models of retinal degeneration. Freshly isolated cells were subjected to whole‐cell patch clamp recordings. During the first 4 weeks after birth of rats, their Müller cells displayed an increase in all membrane currents, particularly in the inward currents elicited at hyperpolarizing potentials. The decrease of the membrane resistance from more than 760 MΩ to less than 50 MΩ was accompanied by a shift of the zero current potential from about −20 mV to −80 mV, similar as earlier observed in developing rabbit Müller cells. These developmental changes were found in pigmented Brown Norway rats as well as in rats with inherited retinal dystrophy (RCS rats). Moreover, an infection of Lewis rats with the Borna disease virus caused substantial neuroretinal degeneration but did not result in a strong reduction of inward currents and of the zero current potential of the Müller cells. Thus, rat Müller cells fail to change their basic membrane properties in two different models of retinal pathology. This is in contrast to human and rabbit Müller cells, which have been shown to undergo dramatic changes of their membrane physiology in response to retinal diseases and injuries. GLIA 34:190–199, 2001. © 2001 Wiley‐Liss, Inc.
The association between depressive symptoms and cognitive decline in community‐dwelling elderly persons
Authors: Comijs Hannie C. , Jonker Cees , Beekman Aartjan T. F. , Deeg Dorly J. H.
Published: September 2002

Objective

To investigate whether depressive symptoms predict specific types of cognitive decline in order to elucidate the association between late life depression and cognitive decline.

Background

Mechanisms underlying the association between late life depression and cognitive decline are still unclear.

Method

Six hundred and forty‐one elderly persons of the Longitudinal Aging Study Amsterdam (LASA) aged 70–85 were examined by means of two measurement occasions over a period of 3 years. Depressive symptoms were assessed by means of the CES‐D. Various cognitive functions were examined using neuropsychological tests.

Results

Depressive symptoms were associated with decline in speed of information processing over a 3‐year period, whereas there was no association between depression and increasing memory impairment or global mental deterioration.

Conclusion

These findings suggest that depressive symptoms are associated with subcortical pathology, most probable white matter lesions. Copyright © 2001 John Wiley & Sons, Ltd.
Temporal patterns of disruptive vocalization in elderly nursing home residents
Authors: Burgio Louis D. , Scilley Kay , Hardin J. Michael , Hsu C.
Published: September 2002

This study used computer‐assisted real‐time data collection procedures to study temporal patterns of disruptive vocalization (DV) in demented nursing home residents. Residents (N = 68) were observed from 8 a.m. to 8 p.m. and total mean duration of DV within hourly blocks was calculated. Analysis of the temporal distribution of DV exhibited by the group of 68 residents indicated a significant cubic trend. Exploratory cluster analysis uncovered three distinct temporal patterns of DV; although two of the patterns are generally supportive of sundowning. Cluster 1 showed a relatively constant pattern of low rate DV. Clusters 2 and 3 showed cyclic trends. Peaks in DV were observed during noontime and in the evening for Cluster 2. Cluster 3 showed peaks in DV in the early morning hours and late afternoon. MANOVA was employed to examine any differences among clusters in age, cognitive status, and ADL status. Univariate analyses indicated that cognitive status was the only factor that differed significantly among clusters, with members of Cluster 1 (constant low rate DV) manifesting higher cognitive status scores than Clusters 2 and 3. A step‐wise discriminant function analysis also showed cognitive status to be the only statistically significant predictor of cluster membership. The authors' note that the scientific literature on agitation is fraught with contradictory findings and assert that inconsistencies may be due to differences across studies in problem definition, method of measurement, and sample size. The results are discussed in relation to these methodological issues and clinical implications of the findings. Copyright © 2001 John Wiley & Sons, Ltd.
High prevalence of anxiety symptoms in hospitalized geriatric patients
Authors: Kvaal Kari , Macijauskiene Jurate , Engedal Knut , Laake Knut
Published: September 2002

Objective

To examine the prevalence of anxiety symptoms in hospitalized geriatric patients.

Design

Controlled cross‐sectional study.

Subjects

Ninety‐eight geriatric in‐patients and 68 healthy home‐dwelling controls of similar age recruited from senior citizen centres.

Outcome measure

Anxiety measured as a current emotional state by Spielberger's State–Trait Anxiety Inventory (STAI).

Results

The geriatric patients scored significantly higher than the controls. Applying Spielberger's recommended cut‐off of 39/40 on the STAI sumscore, 41% of the female and 47% of the male geriatric patients might be suspected of suffering from significant anxiety symptoms. Patients with chronic obstructive pulmonary disease tended to score higher; otherwise no relationship was found between the STAI sumscore and type of chronic somatic disease, nor between the STAI sumscore and number of drugs in regular use.

Conclusions

STAI proved feasible for use in the elderly. The scoring on the STAI is high in geriatric in‐patients. Further studies are needed to clarify to what extent this relates to a high prevalence of anxiety disorders. Copyright © 2001 John Wiley & Sons, Ltd.
The Pummerer‐like reaction of 2,5‐bis(trimethylsilyl)thiophene S‐oxide with trifluoroacetic anhydride: intermediary formation of sulfurane [10‐S‐4(C2O2)] (λ4‐sulfane)
Authors: Sato Soichi , Zhang Shao‐Zhong , Furukawa Naomichi
Published: September 2002

On treatment of a 2,5‐bissilylsubstituted thiophene S‐oxide or dibenzothiophene S‐oxide with trifluoroacetic anhydride, the equillibria between the corresponding substrates and hypervalent sulfur compounds (sulfurane or λ4‐sulfane) have now been first detected by low temperature NMR experiments. By elevating the temperature to room temperature, in the case of the thiophene S‐oxide, the sulfurane detected was converted to 3‐thiolene‐2‐one quantitatively via a Pummerer‐like reaction. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:444–450, 2001
Ulnar versus radial forearm flap in head and neck reconstruction: An experimental and clinical study
Authors: Sieg Peter , Bierwolf Stephan
Published: September 2002

Background

To consider the pros and cons of the microvascular ulnar forearm flap compared with its radial counterpart, this study compares the use of these two flaps for head and neck reconstruction.

Methods

In 75 patients, 51 ulnar and 24 radial forearm flaps were used. Both groups were compared regarding flap dissection, suitability of the flap for the recipient region, complication rate, and secondary morbidity in the donor region. Furthermore, in 40 healthy volunteers, the thickness of the subcutaneous tissue layer was measured by use of ultrasonography.

Results

Flap survival rate, respectively wound healing, in the recipient region showed no differences. Clinical and experimental results demonstrated a thinner subcutaneous layer in the ulnar aspect of the forearm. Compared with its radial equivalent, closure of the ulnar donor side by skin grafting resulted in a significantly lower complication rate.

Conclusions

The ulnar forearm flap is favored because of the less hairy skin of the ulnar forearm region, the thinner layer of subcutaneous tissues, and the more conveniently located donor area. The ulnar forearm pedicle is long compared with alternative transplants but shorter than the radial equivalent. © 2001 John Wiley & Sons, Inc. Head Neck 23: 967–971, 2001.
The behaviour of 39 pesticides in surface waters as a function of scale
Authors: Capel Paul D. , Larson Steven J. , Winterstein Thomas A.
Published: September 2002

A portion of applied pesticides runs off agricultural fields and is transported through surface waters. In this study, the behaviour of 39 pesticides is examined as a function of scale across 14 orders of magnitude from the field to the ocean. Data on pesticide loads in streams from two US Geological Survey programs were combined with literature data from field and watershed studies. The annual load as percent of use (LAPU) was quantified for each of the fields and watersheds and was used as the normalization factor across watersheds and compounds. The in‐stream losses of each pesticide were estimated for a model stream with a 15 day travel time (similar in characteristics to the upper Mississippi River). These estimated in‐stream losses agreed well with the observed changes in apparent LAPU values as a function of watershed area. In general, herbicides applied to the soil surface had the greatest LAPU values and minimal in‐stream losses. Soil‐incorporated herbicides had smaller LAPU values and substantial in‐stream losses. Insecticides generally had LAPU values similar to the incorporated herbicides, but had more variation in their in‐stream losses. On the basis of the LAPU values of the 39 pesticides as a function of watershed area, a generalized conceptual model of the movement of pesticides from the field to the ocean is suggested. The importance of considering both field runoff and in‐stream losses is discussed in relation to interpreting monitoring data and making regulatory decisions. Published in 2001 by John Wiley & Sons, Ltd.
Evaluation of persistent hydrophobic organic compounds in the Columbia River Basin using semipermeable‐membrane devices
Authors: McCarthy Kathleen A. , Gale Robert W.
Published: September 2002

Persistent hydrophobic organic compounds are of concern in the Columbia River because they have been correlated with adverse effects on wildlife. We analysed samples from nine main‐stem and six tributary sites throughout the Columbia River Basin (Washington and Oregon) for polychlorinated dibenzo‐p‐dioxins, dibenzofurans, polychlorinated biphenyls, organochlorine pesticides, and priority‐pollutant polycyclic aromatic hydrocarbons. Because these compounds may have important biological consequences at aqueous concentrations well below the detection limits associated with conventional sampling methods, we used semipermeable‐membrane devices to sample water and achieved parts‐per‐quintillion detection limits. All of these compound classes were prevalent within the basin, but concentrations of many analytes were highest in the vicinity of Portland–Vancouver, indicating that the Willamette subbasin—and perhaps the urban area in particular—is an important source of these compounds. Data collected during basin low‐flow conditions in 1997 and again during basin high‐flow conditions in 1998 indicate that in‐stream processes such as dilution by relatively clean inflows, and flow through island hyporheic zones may be important mechanisms for attenuating dissolved concentrations of hydrophobic compounds. Published in 2001 by John Wiley & Sons, Ltd.
The glutathione defense system in the pathogenesis of rheumatoid arthritis
Authors: Hassan M. Q. , Hadi R. A. , Al‐Rawi Z. S. , Padron V. A. , Stohs S. J.
Published: September 2002

In order to assess a possible role of the natural glutathione defense system in the pathogenesis of rheumatoid arthritis (RA), serum reduced glutathione levels (GSH), glutathione reductase (GSR), glutathione S‐transferase (GST), glutathione peroxidase (GSH‐Px) and alkaline phosphatase (ALP) activities, lipid peroxidation (MDA content) and indexes of inflammation were evaluated in 58 rheumatic patients. Rheumatoid athritis was associated with significant depletion (ca. 50%) in GSH levels compared with normal control subjects. Serum levels of the detoxifying enzymes GSR and GSH‐Px decreased by ca. 50% and 45%, respectively, whereas a threefold increase in the activity of GST was observed. A 1.2‐fold increase in ALP was observed in patients with RA. These effects were accompanied by a 3.1‐fold increase in serum MDA content. The MDA content was higher in RA patients who were seropositive for rheumatoid factor as well as positive for C‐reactive proteins. The erythrocyte sedimentation rate for all patients with RA was approximately 13.8‐fold higher than for the control group, and was higher among RA patients who were positive for C‐reactive proteins and exhibited seropositivity for rheumatoid factor. Patients with RA receiving gold therapy exhibited significantly lower MDA levels whereas all other factors that were measured were not effected. The results support a hypothesis that defense mechanisms against reactive oxygen species are impaired in RA. Copyright © 2001 John Wiley & Sons, Ltd.
Assessment of parameters associated to the risk of PVC catheter reuse
Authors: Granados D. L. , Jiménez A. , Cuadrado T. R.
Published: September 2002

The practice of single use devices (SUD) recycling raises public health concerns, primarily with regard to the potential risks of infection and device malfunction. These concerns have led to a Food and Drug Administration (FDA) revision of the present regulations. The purpose of our work is to identify different material parameters that could contribute to the health risks associated with the practice of reprocessing PVC catheters for use in other patients. Ethylene oxide hospital‐reprocessed central venous catheter samples were obtained from the stock of a health‐care institution. One device trademark was selected, and samples that had been used 8 and 24 times were compared with new ones. In order to determine the total percentage of extractables, supercritical fluid extraction (SFE) was used, and off‐line gas‐chromatography–flame‐ionization detection (GC‐FID) was employed for identification and quantitation of bis‐(2‐ethyl hexil)phthalate (DEHP).Storage modulus (E') and dissipation factor (tan δ curves were obtained by dynamic mechanical analysis (DMA). Successive catheter recycles produced increased plasticizer loss, increased glass transition temperature (Tg) and E', widening of tan δ curve with a simultaneous shift to higher temperature, small decrease of weight average molecular weight (Mw), increased surface roughness, and increased appearance of surface grooves (severe damage). The magnitude of biomaterial parameter changes measured suggests that reuse could alter the original device performance. Examples of possible adverse clinical events include leaching of toxic agents, device rigidization or breakage, increased catheter protein retention, or the promotion of bacterial adhesion by device topography modification. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 58: 505–510, 2001
An insight into the mechanism of cytotoxicity of ricin to hepatoma cell: Roles of Bcl‐2 family proteins, caspases, Ca2+‐dependent proteases and protein kinase C
Authors: Hu Rong‐gui , Zhai Qi‐wei , Liu Wang‐yi , Liu Xin‐yuan
Published: September 2002

The ability of ricin, a type II ribosome‐inactivating protein, to induce hepatoma cell (BEL7404) to apoptosis in vitro was examined by fluorescence microscopy, flow cytometry, and DNA fragmentation assay. As a Bcl‐2 lacking model, BEL7404 bore unique advantage to study the effect of over‐expressing Bcl‐2 on the apoptosis induced by the inhibitor of protein synthesis. By establishing a Bcl‐2 over‐expressing cell line (BEL7404/ Bcl‐2), we found that Bcl‐2 could promote the survival of the hepatoma cell against ricin insult. The ricin‐induced apoptosis of BEL7404 was accompanied by increased expression of Bak and decreased levels of Bcl‐xl and Bax. Caspases and PARP cleavage activity were found to be implicated in the death process. Through the inhibitor tests, our results excluded the participation of calcium‐dependent proteases or protein kinase C in the apoptotic process induced by ricin, though an elevation of intracellular calcium did occur as an immediate response to ricin treatment. Cycloheximide, another protein synthesis inhibitor, did synergistically enhance rather than inhibit the cytotoxicity of ricin to hepatoma cell BEL7404. Actually, cycloheximide alone was able to induce hepatoma cell BEL7404 to death that could also be inhibited by over‐expressing Bcl‐2. The elevation of apoptotic protein Bak was discussed to challenge the notion that ricin exerted its cytotoxicity through nonspecific inhibition of all the de novo protein synthesis. J. Cell. Biochem. 81: 583–593, 2001. © 2001 Wiley‐Liss, Inc.
DOIT: a program to calculate thermal rate constants and mode‐specific tunneling splittings directly from quantum‐chemical calculations
Authors: Smedarchina Zorka , Fernández‐Ramos Antonio , Siebrand Willem
Published: September 2002

In this contribution we discuss computational aspects of a recently introduced method for the calculation of proton tunneling rate constants, and tunneling splittings, which has been applied to molecules and complexes, and should apply equally well to bulk materials. The method is based on instanton theory, adapted so as to permit a direct link to the output of quantum‐chemical codes. It is implemented in the DOIT (dynamics of instanton tunneling) code, which calculates temperature‐dependent tunneling rate constants and mode‐specific tunneling splittings. As input, it uses the structure, energy, and vibrational force field of the stationary configurations along the reaction coordinate, computed by conventional quantum‐chemical programs. The method avoids the difficult problem of calculating the exact least‐action trajectory, known as the instanton path, and instead focusses on the corresponding instanton action, because it governs the dynamic properties. To approximate this action for a multidimensional system, the program starts from the one‐dimensional instanton action along the reaction coordinate, which can be obtained without difficulty. It then applies correction terms for the coupling to the other vibrational degrees of freedom, which are treated as harmonic oscillators (transverse normal modes). The couplings are assumed linear in these modes. Depending on the frequency and the character of the transverse modes, they may either decrease or increase the action, i.e., help or hinder the transfer. A number of tests have shown that the program is at least as accurate as alternative programs based on transition‐state theory with tunneling corrections, and is also much less demanding in computer time, thus allowing application to much larger systems. An outline of the instanton formalism is presented, some new developments are introduced, and special attention is paid to the connection with quantum‐chemical codes. Possible sources of error are investigated. To show the program in action, calculations are presented of tunneling rates and splittings associated with triple proton transfer in the chiral water trimer. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 787–801, 2001
Renal infarct: Contrast‐enhanced power Doppler sonographic findings
Authors: Yücel Cem , Özdemir Hakan , Akpek Sergin , Gürel Kamil , Kapucu L. Özlem , Araç Mehmet
Published: September 2002

Power Doppler sonography (PDUS) is a promising technique for the diagnosis of renal infarcts. PDUS's efficacy may be enhanced by using sonographic contrast agents. We evaluated 3 cases of renal infarction using PDUS and the sonographic contrast agent Levovist. The findings were compared with those of other imaging modalities, such as scintigraphy, CT, and angiography. In case 1, PDUS showed a patent interlobar artery only in the lower part of the right kidney and no other perfusion of the right renal parenchyma. Contrast‐enhanced PDUS showed patchy areas of preserved perfusion in the lower and middle‐upper anterior portions of the kidney. In case 2, PDUS showed diffuse and patchy perfusion defects in the anterolateral portion of the right kidney. On contrast‐enhanced PDUS, no signal enhancement was seen in these areas, but the perfusion defects were better delineated. In case 3, PDUS showed no perfusion in the upper pole of the kidney; the nonperfused area extended to the posterior upper portion of the kidney but could not be distinguished from normal tissue. After injection of the contrast agent, there was no enhancement of the posterior extension of the upper pole infarct, but Doppler signals from the surrounding normal parenchyma were enhanced, so the area was more clearly demarcated. The administration of the contrast agent facilitated the visualization of the infarcts in all 3 cases. © 2001 John Wiley & Sons, Inc. J Clin Ultrasound 29:237–242, 2001.
Ciliary protein turnover continues in the presence of inhibitors of golgi function: Evidence for membrane protein pools and unconventional intracellular membrane dynamics
Authors: Stephens Raymond E.
Published: September 2002

The intimate association of the Golgi apparatus with cilia suggests a functional alliance. To explore the relationship between the synthesis and processing of membrane constituents and the turnover or regeneration of cilia, parallel cultures of gastrula‐stage sea urchin embryos were pulse‐chase labeled with 3H‐leucine in the presence of monensin, brefeldin A, or colchicine. Steady‐state labeled cilia were isolated, and the embryos were allowed to regenerate cilia, which were then isolated after the equivalent of two normal regeneration times. Regeneration was absent in colchicine, minimal in monensin, and inhibited about 40% by brefeldin A. Both monensin and brefeldin A effectively inhibited the post‐translational processing of prominent phosphatidylinositoylated and palmitoylated membrane proteins and the axoneme‐associated transmembrane Spec3 protein, yet most other membrane plus matrix and 9+2 axonemal proteins were labeled to levels indistinguishable from untreated controls. However, total protein analysis of the membrane plus matrix fractions showed a substantial increase in glycoproteins and the calsequestrin‐like protein ECaSt/PDI after treatment at steady‐state with all three inhibitors and after regeneration in brefeldin A. Other constituents of this compartment, such as membrane‐associated tubulin, calmodulin, and a 53‐kDa calcium‐binding protein, were unchanged. Therefore, inhibition of Golgi function via three different mechanisms left 9+2 protein turnover undiminished but resulted in an accumulation, in the cilium, of already‐processed membrane pool constituents and a normally ER‐resident protein. A disproportionate elevation of HSP70 suggests that a novel stress response may be involved in inhibiting ciliary regeneration or promoting glycoprotein augmentation. J. Exp. Zool. 289:335–349, 2001. © 2001 Wiley‐Liss, Inc.
A Graph with cover degeneracy less than chromatic number
Authors: Pyatkin A.V.
Published: September 2002

This note contains an example of a 4‐chromatic graph which admits a vertex partition into three parts such that the union of every two of them induces a forest. © 2001 John Wiley & Sons, Inc. J Graph Theory 37: 243–246, 2001
Fiscal federalism and government size in transition economies: the case of Moldova
Authors: De Mello Luiz
Published: September 2002

This paper examines the relationship between fiscal decentralization—the assignment of revenue sources and expenditure functions across government levels—and government size in Moldova. The empirical results—based on data for a cross‐section of Moldovan sub‐national government in 1998—suggest that fiscal decentralization is associated with larger sub‐national governments and that the country's revenue‐sharing system imposes a constraint on sub‐national revenue mobilization capacity. Copyright © 2001 John Wiley & Sons, Ltd.
Molecularly imprinted polymers from nicotinamide and its positional isomers
Authors: Fu Qiang , Zheng Ning , Li Yuan Zong , Chang Wen Bao , Wang Zong Mu
Published: September 2002

Imprinted polymers were prepared for nicotinamide and its positional isomers. The influence of porogenic solvent and functional monomer on recognition properties of the polymer was compared. The results indicated that two functional groups, the heterocyclic nitrogen and the amide group, in the nicotinamide or isonicotinamide molecule have a synergistic effect in binding to the polymer. The polymers prepared with nicotinamide and isonicotinamide can be used as HPLC stationary phase for the separation of positional isomers of nicotinamide or isonicotinamide, while the polymer prepared with picolinamide showed no specificity toward the template. The mechanisms for the differences in recognition are discussed. In addition to the retention of polymers to their templates the polymers also displayed excellent retention to nicotinic acid and isonicotinic acid, compounds structurally similar to the template. This dual recognition property of the polymer may be useful in circumstances where the preparation of a polymer for a specific template may be problematic because of poor stability or solubility. Copyright © 2001 John Wiley & Sons, Ltd.

Abbreviations used:

AIBN

2,2′‐azo‐bis‐iso‐butyronitrile

EGDMA

ethylene glycol dimethacrylate

HPLC

high performance liquid chromatography

MAA

methacrylic acid

MIPs

molecular imprinted polymers

NAM

nicotinamide.
Analysis of maximum and minimum daily temperatures recorded at Fabra Observatory (Barcelona, NE Spain) in the period 1917–1998
Authors: Serra C. , Burgueño A. , Lana X.
Published: September 2002

Daily maximum and minimum temperatures recorded without interruption at Fabra Observatory (Barcelona) from 1917 to 1998 are analysed studying their homogeneity, randomness, possible trends and their statistical significance, and time irregularities detected by means of concepts of entropy and spectral power analysis. The homogeneity of the series is tested on a monthly scale using the adaptive Kolmogorov–Zurbenko filter. With respect to the randomness of the time series, the von Neumann ratio test is applied to standardized values of extreme temperatures in four different time‐scales (daily, monthly, seasonal and annual). The statistical significance of trends is quantified by applying the Spearman and Mann–Kendall tests to daily, monthly and seasonal data. The Mann–Kendall sequential test also leads to the detection of sharp changes in the time series when monthly data is analysed. The quantification of irregularities through entropy is investigated for standardized temperatures on daily, monthly and seasonal scales, based on the concept of mathematical information theory. Periodicities derived from spectral power analyses are checked with the hypothesis of white‐noise and Markov red‐noise stochastic processes. The most notable features, common to maximum and minimum temperatures, are the lack of randomness of the series for all the time‐scales considered and the different trends obtained for the periods 1917–1980 and 1917–1998, which are confirmed by the Spearman and sequential Mann–Kendall tests. Nevertheless, the maximum and minimum temperature series show quite a different behaviour from the point of view of results concerning time irregularities in terms of entropy and periodicities. The main features of the results are discussed by comparing them with those obtained for other areas of the Mediterranean domain. Copyright © 2001 Royal Meteorological Society
Spatial distribution of seasonal rainfall trends in a western Mediterranean area
Authors: González‐Hidalgo J.C. , De Luis M. , Raventós J. , Sánchez J.R.
Published: September 2002

Changes in seasonal patterns of rainfall are key ecological factors. The definition of the spatial scale on which these changes can occur is particularly relevant in Mediterranean areas, where problems related to the variability of the pluviometric regime vary from one place to another. The region of Valencia is a good example of this kind of variability in rainfall regimes. To study changes in seasonal means and variability, we have applied non‐parametric (Spearman test) and parametric techniques (linear model) to data from 97 pluviometric stations during the World Meteorological Organization (WMO) normal period, 1961–1990. Special emphasis has been placed on the analysis of the spatial pattern of trends in means and variability. For this purpose, we have used a modified version of the Cramér–von Mises test in order to define subregional areas with similar rainfall evolution. Our results show a high spatial heterogeneity in rainfall evolution. The striking feature is the progressive dryness in the autumn season accompanied by an increase in interannual variability. Increases in winter and summer interannual variability, and decreases in rainfall amounts in winter are dominant too. We discuss these results in relation to rainfall generation mechanisms and their ecological implications. Copyright © 2001 Royal Meteorological Society
20th century droughts in southern Africa: spatial and temporal variability, teleconnections with oceanic and atmospheric conditions
Authors: Richard Yves , Fauchereau Nicolas , Poccard Isabelle , Rouault Mathieu , Trzaska Sylwia
Published: September 2002

Southern African rainfall does not show any trend to desiccation during the 20th century. However, the subcontinent experienced particularly severe droughts in the 1980s and at the beginning of the 1990s and the magnitude of the interannual summer rainfall variability shows significant changes. Modifications of the intensity and spatial extension of droughts is associated with changes in ocean–atmosphere teleconnection patterns.

This paper focuses mostly on the well‐documented 1950–1988 period and on late summer season (January–March). A principal component analysis on southern African rainfall highlights modifications of the rainfall variability magnitude. The 1970–1988 period had more variable rainfall, and more widespread and intense droughts than the 1950–1969 period.

To investigate the potential modifications of the associated ocean–atmosphere teleconnection patterns, a composite analysis is performed on sea‐surface temperature (SST) and National Center for Environmental Protection (NCEP) atmospheric parameters, according to the 5 driest years of both sub‐periods. Significant changes are shown in ocean–atmosphere anomaly patterns coincident with droughts for both sub‐periods. The 1950–1969 droughts were associated with regional ocean–atmosphere anomalies, mainly over the southwest Indian Ocean region. In contrast, during the 1970–1988 droughts near‐global anomalies were observed in the tropical zone, corresponding to El Niño–Southern Oscillation (ENSO) phenomenon.

Within the whole century, significant correlations between Southern Oscillation Index (SOI) and southern African Rainfall Index (SARI) were found in the periods (1900–1933 and 1970–1998) when SOI and SARI experienced high variability, and when southern Africa was affected by intense and extended droughts. During periods of low SOI (1934–1969), correlations became less significant and droughts were less intense and widespread. Copyright © 2001 Royal Meteorological Society
Degradation and metabolism of 14C‐labelled proanthocyanidins from carob (Ceratonia siliqua) pods in the gastrointestinal tract of the rat
Authors: Abia Rocío , Fry Stephen C
Published: September 2002

The aim of the work was to study the binding, degradation and metabolism of dietary condensed tannins in the gastrointestinal tract of an omnivore. Young pods of carob (Ceratonia siliqua L) were radiolabelled by in vivo feeding of 14CO2, trans‐[U‐14C]cinnamate or L‐[U‐14C]phenylalanine. [14C]Proanthocyanidins (condensed tannins) were extracted with acetone/water (3:1 v/v), isolated on Sephadex LH‐20 and fed to rats by gavage. After 4 and 18 h, 90–94% of the gavaged 14C was in the gut contents and/or faeces. Much of the gavaged 14C (57%), predominantly that originally in tannins of high degree of polymerisation (DP), became insolubilised, mainly in the form of protein–tannin complexes. Some of the [14C]tannins that remained soluble decreased in DP, especially in the small intestine and caecum. A further fraction (12% of the 14C gavaged) underwent chemical modifications in the gut to form soluble, non‐tannin compounds. Small proportions of the 14C were found in the liver (1.0–1.5%), urine (1–2%) and 14CO2 (1–2%). We conclude that proanthocyanidins are not inert within the gut but undergo various modifications which may affect the nutrition of the animal.

© 2001 Society of Chemical Industry
The mechanism of neutral amino acid decomposition in the gas phase. The elimination kinetics of N,N‐dimethylglycine ethyl ester, ethyl 1‐piperidineacetate, and N,N‐dimethylglycine
Authors: Ensuncho Adolfo , Lafont M. Jennifer , Rotinov Alexandra , Domínguez Rosa M. , Herize Armando , Chuchani Gabriel , Quijano Jairo
Published: September 2002

The gas‐phase elimination kinetics of the ethyl ester of two α‐amino acid type of molecules have been determined over the temperature range of 360–430°C and pressure range of 26–86 Torr. The reactions, in a static reaction system, are homogeneous and unimolecular and obey a first‐order rate law. The rate coefficients are given by the following equations. For N,N‐dimethylglycine ethyl ester:
log k1(s−1) = (13.01 ± 3.70) − (202.3 ± 0.3)kJ mol−1 (2.303 RT)−1
For ethyl 1‐piperidineacetate:
log k1(s−1) = (12.91 ± 0.31) − (204.4 ± 0.1)kJ mol−1 (2.303 RT)−1
The decompositon of these esters leads to the formation of the corresponding α‐amino acid type of compound and ethylene. However, the amino acid intermediate, under the condition of the experiments, undergoes an extremely rapid decarboxylation process. Attempts to pyrolyze pure N,N‐dimethylglycine, which is the intermediate of dimethylglycine ethyl ester pyrolysis, was possible at only two temperatures, 300 and 310°C. The products are trimethylamine and CO2. Assuming log A = 13.0 for a five‐centered cyclic transition‐state type of mechanism in gas‐phase reactions, it gives the following expression: log k1(s−1) = (13.0) − (176.6)kJ mol−1 (2.303 RT)−1. The mechanism of these α‐amino acids differs from the decarbonylation elimination of 2‐substituted halo, hydroxy, alkoxy, phenoxy, and acetoxy carboxylic acids in the gas phase. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33:465–471, 2001
Factorial design analysis of the catalytic activity of di‐imine copper(II) complexes in the decomposition of hydrogen peroxide
Authors: Alves W. A. , De Almeida Azzellini M. A. , De Costa Ferreira A. M. , Bruns R. E.
Published: September 2002

Factorial design analysis was applied to the study of the catalytic activity of di‐imine copper(II) complexes, in the decomposition of hydrogen peroxide. The studied complexes show a tridentate imine ligand (apip), derived from 2‐acetylpyridine and 2‐(2‐aminoethyl)pyridine, and a hydroxo or an imidazole group at the fourth coordination site of the copper ion. The factorial design models for both [Cu(apip)imH]2+ and [Cu(apip)OH]+ were similar. Increasing the peroxide concentration from 3.2 × 10−3 to 8.1 × 10−3 mol L−1 resulted in increased oxygen formation. Increasing the pH from 7 to 11 also increased oxygen formation and had an effect about twice as large as the peroxide one. Both complexes also had an important interaction effect between peroxide concentration and pH. However, increasing the catalyst concentration led to a decrease in total oxygen formation. The obtained results were corroborated by further data, achieved by using the usual univariate method, and helped to elucidate equilibrium steps occurring in the studied systems. In very alkaline solutions, the studied [Cu(apip)imH]2+ complex can form the corresponding dinuclear species, [Cu2(apip)2im]3+. While the mononuclear complex proved to be an efficient catalyst in hydrogen peroxide decomposition, the corresponding dinuclear compound seemed to be able to coordinate with the dioxygen molecule, inhibiting its observed release. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 472–479, 2001
Parametric and temperature‐sensitivity study of resonance frequency of microstrip antennas using spectral‐domain method
Authors: Kedar Ashutosh , Gupta K. K. , Srivastava G. P. , Kataria N. D.
Published: September 2002

In the present paper, a study is carried out to visualize the effects of various design parameters, including temperature, on the resonant frequency of a microstrip patch antenna. The analysis is carried out using the spectral‐domain method with efficient evaluation of infinite 2‐D reaction integrals improving the rate of convergence. Some of the numerical results are compared with the experimental data. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 276–280, 2001.
Silicon‐29 NMR study of the formation of monomethoxysilicic acid in methanolic alkaline silicate solutions
Authors: Samadi‐Maybodi Abdolraouf , Harris Robin K. , Naser Azizi S. , Kenwright Alan M.
Published: September 2002

Silicon‐29 NMR spectra were obtained for more than 20 aqueous alkaline silicate solutions containing methanol. A signal assigned to CH3OSi(OH)3 or one of its deprotonated congeners was studied in detail for the first time for the solution conditions involved. Its appearance was monitored as a function of the solution compositions. The pseudo‐equilibrium constant for its formation is of the order of 0.65. Copyright © 2001 John Wiley & Sons, Ltd.
Requirement of cyclin B2, but not cyclin B1, for bipolar spindle formation in frog (Rana japonica) oocytes
Authors: Kotani Tomoya , Yoshida Noriyuki , Mita Koichi , Yamashita Masakane
Published: September 2002

Cyclin B, the regulatory subunit of maturation‐promoting factor (MPF), comprises several subtypes that are presumed to confer different functions on MPF although no direct evidence has been provided to date. To clarify the difference in the roles of cyclins B1 and B2, we used frog (Rana japonica) oocytes in which MPF is formed only after progesterone stimulation because it is possible to produce oocytes containing either cyclin B1‐MPF or cyclin B2‐MPF by antisense RNA‐mediated translational inhibition of each mRNA. Using this advantage, we investigated the functions of cyclins B1 and B2 and obtained the following results: (a) oocytes synthesizing cyclin B2‐MPF underwent meiosis I and II with formation of a bipolar spindle at each metaphase; (b) oocytes synthesizing cyclin B1‐MPF formed a monopolar spindle at metaphase I and extruded an abnormal polar body; and (c) both oocytes underwent germinal vesicle breakdown (GVBD) and chromosome condensation. Immunocytochemical observations also revealed continuous localization of cyclin B2 on the spindle during meiosis. These results provide evidence of the requirement of cyclin B2, but not cyclin B1, for organizing the bipolar spindle, though either cyclin B1 or B2 is redundant for inducing GVBD and chromosome condensation. Mol. Reprod. Dev. 59:199–208, 2001. © 2001 Wiley‐Liss, Inc.