bluuebunny/crossref_metadata_2025 huggingface dataset:
Selective dissection of levels II–III with intraoperative control of the upper and middle jugular nodes: A therapeutic option for the no neck
Authors: León Xavier , Quer Miquel , Orús César , Sancho Francisco José , Bagué Silvia , Burgués Joaquim
Published: September 2002

Background

Selective neck dissections are accepted elective treatment in N0 patients. We present the results of a dissection of levels II to III and intraoperative pathologic control of a sample of subdigastric and supraomohyoid nodes in a group of patients with laryngeal carcinoma. When intraoperative analysis was positive, dissection of levels IV and V was completed.

Methods

Between 1991 and 1997, 145 neck dissections with intraoperative control were carried out in 79 patients with laryngeal carcinomas. Postoperative radiotherapy was used in 49 patients.

Results

There were occult metastases in 29 neck dissections (20%). In 22 cases (15%), tumor was found in the nodes sent to intraoperative pathologic study, and dissection of levels IV and V was completed. In 7 additional cases tumor was found in the postoperative study. The sensitivity of the use of frozen sections in the detection of occult metastases was 76%. In no case were positive nodes found at level V. There was no regional relapse in any of the 145 selective neck dissections.

Conclusions

The lateral selective neck dissection is an effective method in the elective treatment of the neck of N0 laryngeal carcinoma patients. Dissection of level IV can be spared when intraoperative biopsy specimens of a sample of the subdigastric and supraomohyoid nodes are negative. According to our results, at present we do not consider it necessary to dissect level V in selective neck dissections in patients with laryngeal carcinoma. © 2001 John Wiley & Sons, Inc. Head Neck 23: 441–446, 2001.
Visualization of muscarinic receptor‐mediated phosphoinositide turnover in the hippocampus of young and aged, learning‐impaired Long Evans rats
Authors: Nicolle Michelle M. , Gallagher Michela , McKinney Michael
Published: September 2002

Hippocampal receptor‐mediated phosphoinositide (PI) turnover is severely blunted in aged rats that demonstrate cognitive deficits in the Morris water maze. To further examine the anatomical localization of this deficit, we examined the topography of muscarinic receptor‐mediated PI turnover in young and aged‐learning impaired rats by taking advantage of an autoradiographic method that visualizes PI turnover by measuring the diacylglycerol (DAG) branch of the PI turnover signal transduction system. Using this method, muscarinic cholinergic receptors were stimulated in hippocampal slices with agonist, and the receptor‐mediated incorporation of [3H]cytidine into [3H]CDP‐DAG was subsequently quantified in subregions of the hippocampus using film autoradiography. Our results show a significant decrease in basal incorporation of [3H]CDP‐DAG in the subiculum and in the dentate gyrus in the aged rats. The muscarinic receptor‐mediated [3H]CDP‐DAG response was significantly blunted in the aged rats in subiculum, CA3, and CA1. In contrast, the receptor‐mediated response was maintained in the dentate gyrus and hilus. These results indicate that the age‐associated impairment in receptor‐mediated PI turnover differs regionally, with a reduction in the subiculum and hippocampus proper that is pronounced relative to the hilus and dentate gyrus. Hippocampus 2001;11:741–746. © 2001 Wiley‐Liss, Inc.
Heritability of hippocampal size in elderly twin men: Equivalent influence from genes and environment
Authors: Sullivan Edith V. , Pfefferbaum Adolf , Swan Gary E. , Carmelli Dorit
Published: September 2002

Recent studies have established that environmental factors can modify hippocampal structure and enhance function in adult rodents, but the extent to which genes and the environment exert differential contributions to hippocampal structural integrity in humans is unknown. Here, we applied the twin model in a large sample of elderly twin men to examine in late life the balance of environmental and genetic effects on the size of the hippocampus in comparison with other brain structures. This study provides novel evidence that the volume of the hippocampus, as measured on MRI, is subject to substantially less genetic control than are comparison brain regions also measured: temporal horn volume, midsagittal area of the corpus callosum, and intracranial volume (ICV). In particular, about 60% of the temporal horn variance and 80% of the callosal and ICV variance was attributable to genetic influences, whereas only 40% of the hippocampal variance was attributable to genetic influences. These results suggest that environment, whether by itself or in interaction with genes, has the potential of exerting greater and possibly longer control in modifying hippocampal size than other brain regions that are under greater genetic control. Considering the potential of environmental modification of this structure suggested by lower heritability, the hippocampus appears well‐suited to support the dynamic processes of encoding and consolidation of new, declarataive memories. Hippocampus 2001;11:754–762. © 2001 Wiley‐Liss, Inc.
Neurogranin null mutant mice display performance deficits on spatial learning tasks with anxiety related components
Authors: Miyakawa Tsuyoshi , Yared Edom , Pak Jhang Ho , Huang Freesia L. , Huang Kuo‐Ping , Crawley Jacqueline N.
Published: September 2002

Neurogranin/RC3 is a protein that binds calmodulin and serves as a substrate for protein kinase C. Neuronally distributed in the hippocampus and forebrain, neurogranin is highly expressed in dendritic spines of hippocampal pyramidal cells, implicating this protein in long‐term potentiation and in learning and memory processes. Null mutation of the neurogranin gene Ng generated viable knockout mice for analysis of the behavioral phenotype resulting from the absence of neurogranin protein. Ng −/− mice were normal on measures of general health, neurological reflexes, sensory abilities, and motor functions, as compared to wild type littermate controls. On the Morris water task, Ng −/− mice failed to reach acquisition criterion on the hidden platform test and did not show selective search on the probe trial. In the Barnes circular maze, another test for spatial navigation learning, Ng −/− mice showed impairments on some components of transfer, but normal performance on time spent around the target hole. Abnormal and idiosyncratic behaviors were detected, that appeared to represent an anxiogenic phenotype in Ng −/− mice, as measured in the light↔dark exploration test and the open field center time parameter. These findings of apparent deficits in spatial learning and anxiety‐like tendencies in Ng −/− support a role for neurogranin in the hippocampally‐mediated interaction between stress and performance. Hippocampus 2001;11:763–775. Published 2001 Wiley‐Liss, Inc.
Noradrenergic regulation of hippocampal place cells
Authors: Tanila Heikki
Published: September 2002

The influence of noradrenergic input to the hippocampus was assessed by recording hippocampal place cells and by modulating the noradrenergic tone with a selective agonist and antagonist of the α2‐autoreceptors. The rats received intraperitoneal injection of 5 μg/kg of dexmedetomidine (DEX), an α2‐agonist, 0.2 mg/kg of atipamezole (ATI), an α2‐antagonist, or saline. Hippocampal place cells were recorded in a familiar rectangular environment and in three types of new environments (rectangle, square, and cylinder). Recordings in the familiar environment were conducted in two phases, either before (early phase) or after (late phase) the exposure to new environments. In the familiar environment, DEX significantly increased the mean firing rate of hippocampal interneurons, while ATI increased the mean firing rate of pyramidal cells. Only ATI in the early phase of the experiment impaired spatial selectivity. Both drugs induced field rotations in the early phase of the study, but in the late phase DEX decreased, while ATI increased field stability in the familiar environment. The drug effects in the new environment were dependent on degree of novelty. No difference between treatments was observed in the new rectangle, but in the square and cylinder, ATI increased the mean firing rate, number of fields, and field area compared to other treatments. Stability of the original firing fields in the familiar rectangle was dependent on type of interfering environment and drug treatment. Exposure to another rectangle had the smallest impact, and exposure to a square the largest impact, on the original field pattern. ATI impaired stability of the original field after exposure to a rectangular and cylinder, while the impairing effect of DEX was only observed after exposure to a cylinder. In conclusion, increased noradrenergic tone increases the firing rate of hippocampal place cells, especially when the experimental situation and environment are new, but this increase is spatially nonselective. Furthermore, manipulation of the noradrenergic tone in either direction leads to instability of firing fields. Hippocampus 2001;11:793–808. © 2001 Wiley‐Liss, Inc.
Tianeptine and paroxetine in major depressive disorder, with a special focus on the anxious component in depression: an international, 6‐week double‐blind study†
Authors: Lepine Jean Pierre , Altamura Carlo , Ansseau Marc , Gutierrez Jose Luis Ayuso , Bitter Istvan , Lader Malcolm , Waintraub Lionel
Published: September 2002

Tianeptine (37.5 mg/day) and paroxetine (20 mg/day) were compared in a population of depressive patients without past or current history of co‐morbid anxiety and/or important anxiolytic treatment. In a 6‐week, double blind trial, the special focus was on anxious symptoms.

Both drugs showed good efficacy on depressive symptomatology, assessed with MADRS and HDRS, but no difference was detected between tianeptine and paroxetine, for any assessment criterion. Despite the choice of selected depressive patients, without any co‐morbid anxious disorder, anxiety scale scores at inclusion (HAMA and BAS) were appreciable but correlated poorly with depressive scores. Both tianeptine and paroxetine improved the apparent anxious component in depression. Tolerability of both drugs was good, although significantly better with tianeptine.

Thus tianeptine and paroxetine are effective and safe treatments for major depression and may also act directly on the anxious component of the psychopathology. Copyright © 2001 John Wiley & Sons, Ltd.
Dissolved and particulate carbon dynamics in a cool‐temperate forested basin in northern Japan
Authors: Shibata Hideaki , Mitsuhashi Hiromune , Miyake Yo , Nakano Shigeru
Published: September 2002

When evaluating forest functions and their responses to climate change, it is important to clarify carbon dynamics in forested basins. Carbon fluxes in litter fall, throughfall, soil solution, groundwater and stream water were determined from November 1997 to October 1998 for a forest stream ecosystem in a cool‐temperate forested basin in the Tomakomai Experimental Forest, Hokkaido University, northern Japan. The annual carbon input to the stream by litter fall was 0·23 gC m−2 year−1, with the greatest flux in the autumn. Owing to biological decomposition of litter in the stream, the carbon concentration in stream particulate organic matter (>0·45 µm) decreased as particle size decreased. The upstream carbon flux was 1·9 gC m−2 year−1, and the annual carbon output in stream water was 7·6 gC m−2 year−1, mainly as dissolved inorganic carbon (DIC), resulting in net carbon output in stream water of 5·7 gC m−2 year−1. The mean dissolved organic carbon (DOC) concentration in soil solution was higher than that in throughfall and stream water. The estimated annual carbon flux from soil in deep (about 1·5 m) soil solution was 4·4 gC m−2 year−1. About 40% of DOC in soil solution was decomposed and converted to DIC in groundwater. These results indicate that carbon dynamics in the forest stream were affected strongly by decomposition of organic matter in the soil–groundwater–stream continuum and by the hydraulic conditions, which are characterized by a large pool of groundwater and high soil permeability. Copyright © 2001 John Wiley & Sons, Ltd.
Evaluation of the groundwater capture zone for modelling of nutrient discharge
Authors: Taniguchi Makoto
Published: September 2002

We evaluated a groundwater capture zone through both chemical analysis of groundwater samples and numerical simulation to model the nutrient discharge by groundwater into Lake Biwa, Japan. Solute concentrations in groundwater decrease with depth near the lakeshore. The capture zone of the groundwater was estimated by solute concentration to be deeper than 100 m below the surface even though a clay layer exists at a depth of 10 to 20 m. Numerical simulations of changes in solute concentrations of groundwater seepage have been made using different values for the groundwater capture zone depth. Calculated concentrations agreed well with observed ones when the depth of the groundwater capture zone is set at 150 m. The combination of the chemical and physical evidence helped us to model nutrient discharge by groundwater. Copyright © 2001 John Wiley & Sons, Ltd.
A good practice guide to the administration of substances and removal of blood, including routes and volumes
Authors: Diehl Karl‐Heinz , Hull Robin , Morton David , Pfister Rudolf , Rabemampianina Yvon , Smith David , Vidal Jean‐Marc , Vorstenbosch Cor Van De
Published: September 2002

This article is the result of an initiative between the European Federation of Pharmaceutical Industries Associations (EFPIA) and the European Centre for the Validation of Alternative Methods (ECVAM). Its objectives are to provide the researcher in the safety evaluation laboratory with an up‐to‐date, easy‐to‐use set of data sheets to aid in the study design process whilst at the same time affording maximum welfare considerations to the experimental animals.

Although this article is targeted at researchers in the European Pharmaceutical Industry, it is considered that the principles underpinning the data sets and refinement proposals are equally applicable to all those who use these techniques on animals in their research, whether in research institutes, universities or other sectors of industry. The implications of this article may lead to discussion with regulators, such as those responsible for pharmacopoeial testing.

There are numerous publications dealing with the administration of test substances and the removal of blood samples, and many laboratories also have their own ‘in‐house’ guidelines that have been developed by custom and practice over many years. Within European Union Directive 86/609EEC1 we have an obligation to refine experiments to cause the minimum amount of stress. We hope that this article will provide background data useful to those responsible for protocol design and review.

This guide is based on peer‐reviewed publications whenever possible, but where this is not possible we have used ‘in‐house’ data and the experience of those on the working party (as well as helpful comments submitted by the industry) for a final opinion. The guide also addresses the continuing need to refine the techniques associated with the administration of substances and the withdrawal of blood, and suggests ways of doing so. Data‐sharing between laboratories should be encouraged to avoid duplication of animal work, as well as sharing practical skills concerning animal welfare and scientific problems caused by ‘overdosing’ in some way or another. The recommendations in this guide refer to the ‘normal’ animal, and special consideration is needed, for instance, during pregnancy and lactation. Interpretation of studies may be confounded when large volumes are administered or excessive sampling employed, particularly if anaesthetics are used. Copyright © 2001 John Wiley & Sons, Ltd.
Peptide models XXXI. Conformational properties of hydrophobic residues shaping the core of proteins. An ab initio study of N‐formyl‐L‐valinamide and N‐formyl‐L‐phenylalaninamide
Authors: Hudáky Péter , Jákli Imre , Császár Attila G. , Perczel András
Published: September 2002

Employing introductory (3‐21G RHF) and medium‐size (6‐311++G** B3LYP) ab initio calculations, complete conformational libraries, containing as many as 27 conformers, have been determined for diamide model systems incorporating the amino acids valine (Val) and phenylalanine (Phe). Conformational and energetic properties of these libraries were analyzed. For example, significant correlation was found between relative energies from 6‐311++G** B3LYP and single‐point B3LYP/6‐311++G**//RHF/3‐21G calculations. Comparison of populations of molecular conformations of hydrophobic aromatic and nonaromatic residues, based on their ab initiorelative energies, with their natural abundance indicates that, at least for the hydrophobic core of proteins, the conformations of Val (Ile, Leu) and Phe (Tyr, Trp) are controlled by the local energetic preferences of the respective amino acids. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 732–751, 2001
Photocatalytic degradation for environmental applications – a review
Authors: Bhatkhande Dhananjay S , Pangarkar Vishwas G , Beenackers Anthony A C M
Published: September 2002

Photocatalysis is a rapidly expanding technology for wastewater treatment. In this review the chemical effects of various variables on the rate of degradation of different pollutants are discussed in detail. The effects of adsorption, temperature, intensity of light, pH, and the presence of anions, cations, etc have been specifically covered. A critical analysis of the available literature data has been made and some general conclusions have been drawn concerning the above mentioned effects. The need for more work on specific points has been brought out.

© 2001 Society of Chemical Industry
Color Doppler sonographic diagnosis of dissecting aneurysm of the superior mesenteric artery
Authors: Wadhwani Raju , Modhe Jagdish , Pandey Kaushal , Gujar Sachin , Sukthankar Rajan
Published: September 2002

We report a case of dissecting aneurysm of the superior mesenteric artery (SMA) diagnosed on gray‐scale and color Doppler sonography and confirmed on angiography. Spontaneous dissection of the SMA is rare, and there are few reported cases of the color Doppler sonographic findings. Gray‐scale sonography revealed an aneurysmal dilatation of the SMA 3–4 cm from the SMA's origin, with an echogenic linear membrane (an intimal flap) within the aneurysm. Color Doppler sonography showed color flow within the aneurysm and showed that the intimal flap separated the aneurysm into 2 lumina. Spectral analysis revealed anterograde flow in the anterior (ie, true) lumen and retrograde flow in the posterior (ie, false) lumen. © 2001 John Wiley & Sons, Inc. J Clin Ultrasound 29:247–249, 2001.
Early carbonic anhydrase induction in the gills of the blue crab, Callinectes sapidus, during low salinity acclimation is independent of ornithine decarboxylase activity
Authors: Henry Raymond P. , Watts Stephen A.
Published: September 2002

Carbonic anhydrase (CA) induction in the gills of the euryhaline blue crab, Callinectes sapidus, was measured in response to lowered environmental salinity. Simultaneous measurements of ornithine decarboxylase (ODC) activity were made in gills and nonbranchial tissues to determine whether ODC activity and the resultant synthesis of polyamines played a role in the initiation and regulation of CA induction. CA induction in the seventh gill pair (G7) was proportional to the decrease in ambient salinity, but activity in the third gill pair (G3) remained unchanged. Induction began by 24 hr after low salinity transfer, much earlier than previously reported, and peaked after 4 days. The magnitude of salinity change affected the magnitude of CA induction only, not the time course. A general cell volume regulatory response, as measured by the appearance of total ninhydrin‐positive substances (TNPS) in the hemolymph, was initiated within 4 hr of low salinity transfer and was complete by 24 hr post‐transfer. General cell swelling may be the initial signal in the pathway of CA induction. ODC activity in the gills of acclimated animals was not influenced by salinity. For crabs transferred from 35 to 25 ppt, ODC activity did not change significantly over the time course of acclimation. There was an early but transient increase in ODC activity in all tissues for crabs acclimated to 28 ppt and transferred to 15 ppt. Induction of ODC activity does not appear to be a precursor for CA induction; therefore, it does not appear that polyamines are substantially involved in the up‐regulation of transport enzyme activity in low salinity. ODC, and resultant polyamine synthesis, may, however, have a role in cell volume regulation. J. Exp. Zool. 289:350–358, 2001. © 2001 Wiley‐Liss, Inc.
Spanning trees with many leaves
Authors: Ding Guoli , Johnson Thor , Seymour Paul
Published: September 2002

We show that if G is a simple connected graph with

and $|V(G)| \,\neq\,t+2$, then G has a spanning tree with > t leaves, and this is best possible. © 2001 John Wiley & Sons, Inc. J Graph Theory 37: 189–197, 2001
Law tradition and institutional quality: some empirical evidence†
Authors: Chong Alberto , Zanforlin Luisa
Published: September 2002

Law tradition of a country is associated with its institutional quality. Countries with a French Civil code tradition display a negative link with bureaucratic development, lack of corruption, credibility of governments and others. Results are maintained even after controlling for regional and colonial variables and, in general, appear robust. Countries with a Common Law tradition show a positive relationship with institutional quality, though not as robust when testing a broad range of specifications. These results are consistent with the hypothesis of Scully, Posner and others, that link origin of laws and economic behaviour. Copyright © 2000 John Wiley & Sons, Ltd.
Actinomycin D Binding to Unstructured, Single‐stranded DNA
Authors: Yoo Hoon , Rill Randolph L.
Published: September 2002

Actinomycin D is an anticancer antibiotic best know for inhibiting transcription by binding double‐stranded DNA. Tight, sequence selective binding of actinomycin to single‐stranded DNA is also known, however, and is implicated in biological activities including inhibition of (−) strand transfer by HIV reverse transcriptase. Oligonucleotide d(GTTAACCATAG) is one of the rare single‐stranded DNAs that lack GC steps yet have high affinity for actinomycin. Oligonucleotide sequence and length requirements for drug binding were investigated by monitoring association of the fluorescent surrogate, 7‐aminoactinomycin D, to d(GTTAACCATAG) and 31 related oligomers. The TAG‐3′ terminal sequence was essential for high‐affinity binding, but was not sufficient. Five oligomers with TAG sequences on or near the 3′‐end had high affinity [Kd ≤ 200 nM (oligomer)]. A sixth oligomer, d(GTAACCATATG), had moderately lower affinity (Kd = 370 nM), and other homologous oligomers had much lower affinity. The minimum length sequence for tight binding of 7‐aminoactinomycin D was identified as only eight nucleotides, corresponding to d(AACCATAG). This octanucleotide is unstructured in the absence of actinomycin, and has the highest drug affinity of all oligomers examined (Kd = 125 nM). These studies show that high‐affinity binding of 7‐aminoactinomycin, and actinomycin D by extension, to single‐stranded DNA does not require pre‐existing secondary structure or any apparent propensity for secondary structure. It is proposed that actinomycin D binds to certain single‐stranded DNA sequences by an induced‐fit mechanism favored by participation of at least eight nucleotides, or the equivalent of four base pairs. Copyright © 2001 John Wiley & Sons, Ltd.

Abbreviations used:

AMD

actinomycin D

7AAMD

7‐aminoactinomycin D

dsDNA

double‐stranded DNA

ssDNA

single‐stranded DNA.
Autoantibody appearance in cytomegalovirus‐infected liver transplant recipients: Correlation with antigenemia
Authors: Varani Stefania , Muratori Luigi , De Ruvo Nicola , Vivarelli Marco , Lazzarotto Tiziana , Gabrielli Liliana , Bianchi Francesco B. , Bellusci Roberto , Landini Maria P.
Published: September 2002

The presence of anti‐endothelial cells (AECA), smooth muscle (SMA), antinuclear (ANA) and antimitochondrial (AMA) autoantibodies, and liver/kidney microsomal antibody type 1 (LKM1) was investigated retrospectively in sera of liver transplant patients and correlated with cytomegalovirus (CMV) infection as determined by the antigenemia test and with the appearance of acute or chronic allograft rejection. Indirect immunofluorescence analysis was carried out in sequential sera from 40 liver transplant patients. Ten out of 23 antigenemia‐positive and none of the antigenemia‐negative patients developed serum autoantibodies (P = 0.002, Fisher's exact test). Anti‐endothelial cell autoantibodies were found in nine cases and SMA in four patients. Antinuclear antibodies were detected in one otherwise autoantibody‐negative patient. All but one case of autoantibody positivity were observed in the high antigenemia group (P < 0.0001, Fisher's exact test). In all but one case, autoantibodies were detected in blood during the antigenemia phase and in most cases in coincidence with or after the antigenemia peak. Even though a statistically significant correlation was not found between autoantibody production and the development of acute or chronic allograft rejection, proportionally more acute rejection cases were observed in the autoantibody‐positive than in the autoantibody‐negative group. It has been speculated that CMV‐induced endothelial damage may be a potent antigenic stimulus, which leads to the production of anti‐endothelial cells autoantibodies. Anti‐endothelial cell autoantibodies may represent not only a marker of cell injury but also contribute to the progression of the inflammatory response leading to the exposure of tissue‐privileged self antigens and the induction of other autoantibodies such as SMA. J. Med. Virol. 66:56–62, 2002. © 2002 Wiley‐Liss, Inc.
Influence of synoptic situations on the precipitation in Kraków (Poland)
Authors: Twardosz Robert , Niedźwiedź Tadeusz
Published: September 2002

The impact of the synoptic situations on the occurrence of precipitation in Kraków is analysed. Daily records of precipitation from the period 1873–1999 were used, as well as the calendar of synoptic situations by T. Niedźwiedź. The study presents annual and long‐term variations of daily precipitation, frequency of the synoptic situations, and frequency of precipitation for particular situations. For the 21 types of synoptic situations, the following characteristics were defined: average daily precipitation and its effectiveness ratio, maximum precipitation and the probability of occurrence of days with or without precipitation. Most precipitation occurs during the advection of air masses from the west and during the cyclonic trough, which is related to high frequency of occurrence of such situations. From among 21 synoptic situations, the following ones are the most favourable for the development of abundant precipitation: northeastern cyclonic situation (NEc), north cyclonic situation (Nc), cyclonic trough (Bc) and centre of low pressure (Cc). Copyright © 2001 Royal Meteorological Society
Performance of statistical downscaling models in GCM validation and regional climate change estimates: application for Swedish precipitation
Authors: Busuioc Aristita , Chen Deliang , Hellström Cecilia
Published: September 2002

This study deals with an analysis of the performance of a general circulation model (GCM) (HadCM2) in reproducing the large‐scale circulation mechanisms controlling Swedish precipitation variability, and in estimating regional climate changes owing to increased CO2 concentration by using canonical correlation analysis (CCA). Seasonal precipitation amounts at 33 stations in Sweden over the period 1899–1990 are used. The large‐scale circulation is represented by sea level pressure (SLP) over the Atlantic–European region.

The link between seasonal Swedish precipitation and large‐scale SLP variability is strong in all seasons, but especially in winter and autumn. For these two seasons, the link is a consequence of the North Atlantic Oscillation (NAO) pattern. In winter, another important mechanism is related to a cyclonic/anticyclonic structure centred over southern Scandinavia. In the past century, this connection has remained almost unchanged in time for all seasons except spring. The downscaling model that is built on the basis of this link is skilful in all seasons, but especially so in winter and autumn. This observed link is only partially reproduced by the HadCM2 model, while large‐scale SLP variability is fairly well reproduced in all seasons. A concept about optimum statistical downscaling models for climate change purposes is proposed. The idea is related to the capability of the statistical downscaling model to reproduce low frequency variability, rather than having the highest skill in terms of explained variance. By using these downscaling models, it was found that grid point and downscaled climate signals are similar (increasing precipitation) in summer and autumn, while in winter, the amplitudes of the two signals are different. In spring, both signals show a slight increase in the northern and southern parts of Sweden. Copyright © 2001 Royal Meteorological Society
Seasonal and interannual variability in atmospheric turbidity over South Africa
Authors: Power Helen C. , Willmott Cort J.
Published: September 2002

Aerosols affect climate by attenuating solar radiation and acting as cloud condensation nuclei. Despite their importance in the climate system, our understanding of the time‐space variability of aerosols is fragmentary. Measurements and reliable estimates of atmospheric turbidity—the total column amount of aerosol—are scarce in most countries and this is especially true in the Southern Hemisphere. Very little is known about the seasonal, interannual and spatial variability of aerosols over the southern half of the globe.

In this paper, we estimate monthly averaged atmospheric turbidity from surface climate data at eight locations in South Africa, regardless of cloud cover. Findings include new estimates of turbidity trends and variability over South Africa. Seasonal trends are evident at many stations, although there is no consistent trend. Over recent decades, turbidity has generally been stable at six of the eight stations. Our methodology can be applied at any location where the requisite climate data are available and, therefore, holds promise for a more complete, and possibly global, climatology of aerosols. Copyright © 2001 Royal Meteorological Society
Oxygen isotope and palaeotemperature records from six Greenland ice‐core stations: Camp Century, Dye‐3, GRIP, GISP2, Renland and NorthGRIP
Authors: Johnsen Sigfus J. , Dahl‐Jensen Dorthe , Gundestrup Niels , Steffensen Jørgen P. , Clausen Henrik B. , Miller Heinz , Masson‐Delmotte Valerie , Sveinbjörnsdottir Arny E. , White James
Published: September 2002

Oxygen isotope variations spanning the last glacial cycle and the Holocene derived from ice‐core records for six sites in Greenland (Camp Century, Dye‐3, GRIP, GISP2, Renland and NorthGRIP) show strong similarities. This suggests that the dominant influence on oxygen isotope variations reflected in the ice‐sheet records was regional climatic change. Differences in detail between the records probably reflect the effects of basal deformation in the ice as well as geographical gradients in atmospheric isotope ratios. Palaeotemperature estimates have been obtained from the records using three approaches: (i) inferences based on the measured relationship between mean annual δ18O of snow and of mean annual surface temperature over Greenland; (ii) modelled inversion of the borehole temperature profile constrained either by the dated isotopic profile, or (iii) by using Monte Carlo simulation techniques. The third of these approaches was adopted to reconstruct Holocene temperature variations for the Dye 3 and GRIP temperature profiles, which yields remarkably compatible results. A new record of Holocene isotope variations obtained from the NorthGRIP ice‐core matches the GRIP short‐term isotope record, and also shows similar long‐term trends to the Dye‐3 and GRIP inverted temperature data. The NorthGRIP isotope record reflects: (i) a generally stronger isotopic signal than is found in the GRIP record; (ii) several short‐lived temperature fluctuations during the first 1500 yr of the Holocene; (iii) a marked cold event at ca. 8.2 ka (the ‘8.2 ka event’); (iv) optimum temperatures for the Holocene between ca. 8.6 and 4.3 ka, a signal that is 0.6‰ stronger than for the GRIP profile; (v) a clear signal for the Little Ice Age; and (vi) a clear signal of climate warming during the last century. These data suggest that the NorthGRIP stable isotope record responded in a sensitive manner to temperature fluctuations during the Holocene. Copyright © 2001 John Wiley & Sons, Ltd.
Estimates of the efficiency of transfer of L‐histidine from blood to milk when it is the first‐limiting amino acid for secretion of milk protein in the dairy cow
Authors: Kim Chang‐Hyun , Choung Jai‐Jun , Chamberlain David G
Published: September 2002

The efficiency of transfer of L‐histidine into milk protein was measured in two experiments in which L‐histidine was infused intravenously into dairy cows eating a basal diet of grass silage and a cereal‐based supplement containing feather meal. Both experiments used Latin square designs, and infusion periods lasted 10 days. In Experiment 1, histidine was infused alone at doses of 3, 6 and 9 g day−1. The output of milk protein increased up to the 6 g day−1 dose but fell back to the basal level when 9 g day−1 was infused. The efficiency of transfer was highest for the 6 g day−1 dose, for which the value was 0.38. In Experiment 2 the same three histidine doses as in Experiment 1 were used, but this time the histidine was accompanied by 8 g L‐methionine, 28 g L‐lysine and 2.5 g L‐tryptophan, to ensure that histidine remained first‐limiting over the whole dose range. The output of histidine in milk protein (Y) increased linearly with histidine dose (X) such that Y  = 0.431 X + 0.070 r  = 0.998; n  = 4, indicating an efficiency of transfer of 0.43.

© 2001 Society of Chemical Industry
Business travellers' perception of service quality: a prefatory study of two European city centre hotels
Authors: Callan Roger J. , Kyndt Gabrielle
Published: September 2002

The business traveller contributes significantly to the turnover of the hotel industry and, with the globalisation of business, this sector shows signs of increasing growth. Service quality has now become one of the main factors used to gain competitive advantage, thus the industry must focus more specifically on the needs and expectations of its business customers. The aim of this paper is to focus on the business travel market and more specifically on the comparison of two hotels in two European cities, Brussels and Manchester. This area of research has not been attempted before and will provide an interesting comparison with findings in USA.

 A literature review identified the relevant attributes used to measure service quality, which were utilised to design a questionnaire, distributed to customers in a five star hotel in Manchester and in Brussels.

The primary data obtained were then compared with the findings of other
researchers. The analysis indicated that Brussels scored the majority of the attributes more highly (many significantly) than did Manchester. This may be influenced by the international profile of the Brussels
respondents who tended to travel on
business more frequently than the
Manchester sample. The comparisons with the USA surveys found some inconsistencies that might be attributed to societal
differences.Copyright © 2001 John Wiley
& Sons, Ltd.
Desorption kinetics of model polar stratospheric cloud films measured using Fourier Transform Infrared Spectroscopy and Temperature‐Programmed Desorption
Authors: Koehler Birgit G.
Published: September 2002

This study combines Fourier transform infrared (FTIR) spectroscopy and temperature‐programmed desorption to examine the evaporation kinetics of thin films of crystalline nitric acid hydrates, solid amorphous H2O/HNO3 mixtures, H2O–ice, ice coated with HCl, and solid HNO3. IR spectroscopy measured the thickness of each film as it evaporated, either at constant temperature or during a linear temperature ramp (temperature‐programmed infrared, TPIR). Simultaneously, a mass spectrometer measured the rate of evaporation directly by monitoring the evolution of the molecules into the gas phase (temperature‐programmed desorption, TPD). Both TPIR and TPD data provide a measurement of the desorption rate and yield the activation energy and preexponential factor for desorption. TPD measurements have the advantage of producing many data points but are subject to interference from experimental difficulties such as uneven heating from the edge of a sample and sample‐support as well as pumping‐speed limitations. TPIR experiments give clean but fewer data points. Evaporation occurred between 170 and 215 K for the various films. Ice evaporates with an activation energy of 12.9 ± 1 kcal/mol and a preexponential factor of 1 × 1032±1.5 molec/cm2 s, in good agreement with the literature. The beta form of nitric acid trihydrate, β–NAT, has an Edes of 15.6 ± 2 kcal/mol with log A = 34.3 ± 2.3; the alpha form of nitric acid trihydrate, α–NAT, is around 17.7 ± 3 kcal/mol with log A = 37.2 ± 4. For nitric acid dihydrate, NAD, Edes is 17.3 ± 2 kcal/mol with log A = 35.9 ± 2.6; for nitric acid monohydrate, NAM, Edes is 13 ± 3 kcal/mol with log A = 31.4 ± 3. The α–NAT converts to β–NAT during evaporation, and the amorphous solid H2O/HNO3 mixtures crystallize during evaporation. The barrier to evaporation for pure nitric acid is 14.6 ± 3 kcal/mol with log A = 34.4 ± 3. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 295–309, 2001
Kinetics of OH reactions with N2H4, CH3NHNH2and (CH3)2NNH2in the gas phase
Authors: Vaghjiani Ghanshyam L.
Published: September 2002

The gas phase reaction kinetics of OH with three di‐amine rocket fuels—N2H4, CH3NHNH2, and (CH3)2NNH2—was studied in a discharge flow tube apparatus and a pulsed photolysis reactor under pseudo‐first‐order conditions in [OH]. Direct laser‐induced fluorescence monitoring of the [OH] temporal profiles in a known excess of the [diamine] yielded the following absolute second‐order OH rate coefficient expressions;k1= (2.17 ± 0.39) × 10−11e(160±30)/T,k2= (4.59 ± 0.83) × 10−11e(85±35)/Tandk3= (3.35 ± 0.60) × 10−11e(175±25)/Tcm3molec−1s−1, respectively, for reactions with N2H4, CH3NHNH2and (CH3)2NNH2in the temperature range 232–637 K. All three reactions did not show any discernable pressure dependence on He or N2buffer gas pressure of up to 530 torr. The magnitude of the weak temperature and the lack of pressure effects of the OH + N2H4reaction rate coefficient suggest that a simple direct metathesis of H‐atom may not be important compared to addition of the OH to one of the N‐centers of the diamine skeleton, followed by rapid dissociation of the intermediate into products. Our findings on this reaction are qualitatively consistent with a previousab initiostudy [3]. However, in the alkylated diamines, direct H‐abstraction from the methyl moiety cannot be completely ruled out. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 354–362, 2001
Oxidation of 3‐(3,4‐dihydroxy phenyl)‐l‐alanine (levodopa) and 3‐(3,4‐dihydroxy phenyl)‐2‐methyl‐l‐alanine (methyl dopa) by manganese(III) in pyrophosphate media: Kinetic and mechanistic study
Authors: Sherigara B. S. , Kumara Swamy B. E. , Subrahmanyam E. V. S. , Ishwar Bhat K.
Published: September 2002

Manganese(III) (Mn(III)) has been stabilized in weakly acidic solution by means of pyrophosphate and the nature of the complex was elucidated spectrophotometrically. Stoichiometry of Mn(III)‐oxidation of levodopa and methyl dopa in pyrophosphate medium was established in the pH range 2.5–4.0 by iodometric and spectrophotometric methods. The reaction shows a distinct variation in kinetic order with respect to [Mn(III)], a first‐order dependence in the pH range 1.9–2.6, decreasing to fractional order above pH 3. Other common features include first‐order dependence on [dopa], positive fractional order dependence on [H+], and inverse first‐order dependence on [Mn(III)] in the pH range studied. The effects of varying ionic strength and solvent composition were studied. Added ions such as SO42− and ClO4− alter the reaction rate, probably due to the change in the formal redox potential of Mn(III)–Mn(II) couple because of the changes in coordination environment of the oxidizing species. Evidence for the transient existence of the free radical intermediate is given. Cyclic voltametric sensing of levodopa and methyl dopa has ruled out the formation of dopaquinones as oxidation products in the pH range studied. Activation parameters have been evaluated using the Arrhenius and Erying plots. Mechanisms consistent with the kinetic data have been proposed and discussed. These studies are expected to throw some light on dopa metabolism. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 449–457, 2001
Comparative analysis ofrasproto‐oncogene mutations in selected mammalian tumors
Authors: Watzinger F. , Mayr B. , Gamerith R. , Vetter C. , Lion T.
Published: September 2002

Point mutations withinrasproto‐oncogenes are frequently detected in human malignancies and in different types of experimentally induced tumors in animals. In contrast to findings in experimental animal models of carcinogenesis, little is known about the incidence ofrasmutations in naturally occurring animal tumors. In the present study, we investigated whether point mutations, particularly within the mutational hot‐spot codons 12, 13, and 61, occur at comparable frequencies in human malignancies and spontaneously occurring tumors in other mammalian species. Two hundred seventy‐nine of the most frequent canine and feline neoplasms were analyzed for changes in mutational hot‐spot regions of the N‐, Ki‐, and Ha‐rasgenes. DNA fragments from exons 1 and 2 of all threerasgenes were amplified by polymerase chain reaction, and the presence of point mutations was assessed by single‐strand conformation polymorphism analysis and direct sequencing of amplified products. Only one sample, a case of canine melanoma, exhibited an Ha‐rasmutation. Thus, our data strongly suggested thatrasmutations at the hot‐spot loci are apparently very rare and do not play a major role in the pathogenesis of the spontaneously occurring canine and feline tumors investigated. These observations were in marked contrast to those in experimental rodent models of carcinogen‐induced mammary and skin tumors that described a consistent association with Ha‐ or Ki‐rasactivation. The role of ras oncogene activation in related human malignancies therefore cannot be readily inferred from studies of experimental carcinogenesis in animal models. © 2001 Wiley‐Liss, Inc.
Use of an arterialized venous flap for resurfacing a circumferential soft tissue defect of a digit
Authors: Chia John , Lim Aymeric , Peng Yeong‐Pin
Published: September 2002

Circumferential defects of digit are uncommon but present a challenging problem to the clinician. The use of simple skin grafts tends to cause tendon adhesions and can limit digital range of motion. The use of local skin flaps, such as a cross‐finger flap, is limited by the considerable skin loss in a defect that is circumferential in nature. Other options have included the use of reversed forearm flap or some free tissue transfer. We report a case in which the circumferential defect of an index finger, measuring 6 cm around the digit and 3 cm long, is resurfaced by the use of a free arterialized venous flap raised from the volar forearm skin. © 2001 Wiley‐Liss, Inc. MICROSURGERY 21:374‐378; 2001
Vascular complication in free tissue transfer to the leg
Authors: Muramatsu Keiichi , Shigetomi Mitsunori , Ihara Koichiro , Kawai Shinya , Doi Kazuteru
Published: September 2002

The lower‐extremity free flap has a high incidence of vascular complication. A retrospective study of 70 free flap transplants in 70 patients (1987–2000) was conducted to investigate factors leading to vascular complication and free flap failure. The overall success rate was 92% (64 of 70 flaps); the incidence of vascular complications was 22% (16 of 70 flaps). Among 16 complicated flaps, 7 were transferred in severely crushed legs, and 4 were in multioperated legs attributable to chronic osteomyelitis. Venous thrombosis occurred in 12 flaps (86%). The success rate of the patients operated on at Yamaguchi University Hospital was higher (96%) than at other hospitals tested. The key factors contributing to improved outcome in free tissue transplantation in the leg were careful preoperative planning for highly traumatized legs and proper selection of the recipient vein and of the hospital at which immediate reexploration can be performed for vascular complicated flaps. © 2001 Wiley‐Liss, Inc. MICROSURGERY 21:362–365 2001
On the diffraction of Poincaré waves
Authors: Martin P. A.
Published: September 2002

The diffraction of tidal waves (Poincaré waves) by islands and barriers on water of constant finite depth is governed by the two‐dimensional Helmholtz equation. One effect of the Earth's rotation is to complicate the boundary condition on rigid boundaries: a linear combination of the normal and tangential derivatives is prescribed. (This would be an oblique derivative if the coefficients were real.) Corresponding boundary‐value problems are treated here using layer potentials, generalizing the usual approach for the standard exterior boundary‐value problems of acoustics. Singular integral equations are obtained for islands (scatterers with non‐empty interiors) whereas hypersingular integral equations are obtained for thin barriers. Copyright © 2001 John Wiley & Sons, Ltd.
Highly efficient L‐band EDFA for DWDM systems employing a self‐generated seed signal
Authors: Mahdi M. A. , Ahmad H.
Published: September 2002

A novel method of a gain‐enhanced long‐wavelength band (L‐band) erbium‐doped fiber amplifier is presented utilizing a gain‐clamped amplifier based on a ring‐laser feedback. The laser output is used as a seed signal into a second‐stage arnplifier, and has improved the L‐band gain for higher dense wavelength‐division multiplexed channels. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 234–236, 2001.
Improved technique of H‐plane nonreciprocal ferrite phase shifter
Authors: Che Wenquan , Yung E. K. N. , Ma Jinping
Published: September 2002

An improved technique for an H‐plane nonreciprocal ferrite phase shifter is introduced in this letter. A numerical analysis is carried out using the finite‐element method (FEM) to determine the effect of the technique quantitatively. Both experimental and numerical results show that the differential phase shift of the improved device has been increased by over 70%. The measured results also show that the insertion loss of the improved device is smoother than that of the old one. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 236–237, 2001.
Estimating the RF attenuation rate via roadside trees with extraction techniques
Authors: Liu Ji‐Chyun , Wei Chia Ping , Chang Dau‐Chyrh , Chang Chung‐Chi , Cheng Ching
Published: September 2002

Modelings of the radio propagation channel are among the most important and fundamental issues. The levels of the desired signal and cochannel interference are associated with the measurement system. A new approach to estimate the RF attenuation rate (AR, dBm/m) with the extraction technique is introduced in this paper. Any changes due to an environmental disturbance or cochannel interference will cancel. The AR can be used to characterize the trees (or medium) with a linear expression. In practice, the attenuation rate results of four roadside trees are described based on data acquired from experiments employing an RF channel sounding system at 1800 MHz. It makes the estimations suitable for wireless communication systems. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 242–246, 2001.