bluuebunny/crossref_metadata_2025 huggingface dataset:
The significance of comorbidity in advanced laryngeal cancer
Authors: Chen Amy Y. , Matson Leslie K. , Roberts Dianna , Goepfert Helmuth
Published: August 2002

Introduction

Cancer patients often have concurrent diseases and conditions known as comorbidities. The aim of this project is to demonstrate the significance of comorbidity in the treatment and outcomes of advanced laryngeal carcinoma.

Methods

A retrospective medical record review of 182 patients with previously untreated T3 or T4 squamous carcinomas of the larynx treated at M. D. Anderson between 1990 and 1995 was performed. Demographic, patient‐specific, tumor‐specific, and outcome measures information were collected. Comorbidity was coded using the Modified Medical Comorbidity Index. Univariate and multivariate analysis with the use of life survival analysis techniques and logistic regression were performed.

Results

The median age at diagnosis was 59.5 years. Most patients were men (69.2%) and Caucasian (73.1%). Laryngeal preservation was performed in 90 patients, and surgical resection was performed in 92 patients. Patients in the two treatment groups had similar comorbidity, locoregional control (65%), and 5‐year survival (37.3%). Patients with either moderate or severe comorbidity had significantly worse overall survival (p = .00014) and worse 5‐year survival than those with no or mild comorbidity (21.8% vs 46.3%, p = .003).

Conclusions

This study demonstrates that comorbidity is significantly associated with survival in a group of patients with identical histology, site, and stage. Comorbid status should be incorporated into the assessment of prognosis and outcome to improve and optimize the management of head and neck cancer patients. © 2001 John Wiley & Sons, Inc. Head Neck 23: 566–572, 2001.
The relationship between training and organizational commitment: A study in the health care field
Authors: Bartlett Kenneth R.
Published: August 2002

This study examines the relationship between employee attitudes toward training and feelings of organizational
commitment among a sample of 337 registered nurses from five hospitals. Using social exchange theory as a
framework for investigating the relationship, the researcher found that perceived access to training, social
support for training, motivation to learn, and perceived benefits of training are positively related to
organizational commitment. Using a three‐component model of organizational commitment, the strongest
relationships appear with the affective form of commitment. The relationship between perceived access to training
opportunities and the affective form of organizational commitment is moderated by job satisfaction but not job
involvement. The findings are discussed for their theoretical and practical application to HRD, for the
management of HRD in health care settings, and for researchers interested in outcomes of HRD.
Characteristics of performance appraisals and their impact on sales force satisfaction
Authors: Pettijohn Charles E. , Pettijohn Linda S. , d'Amico Michael
Published: August 2002

A study of the relationship between performance appraisal characteristics and salesperson job satisfaction indicated that when appraisals provide clear criteria, the criteria meet with the salesperson's approval, and the appraisals are perceived as fair and used in determining rewards, salesperson job satisfaction increases. These results support previous findings that the critical determinants of appraisal effectiveness are not criteria‐driven but rather are largely determined by factors that managers can influence.
The Use of Person–Group Fit for Employment Selection: A Missing Link in Person–Environment Fit
Authors: Werbel James D. , Johnson Danny J.
Published: August 2002

Given an increased emphasis on work teams in organizations, it is important to select applicants based on their
ability to make contributions to a given work team. This paper proposes that person–group fit should be
useful to select applicants for work teams and suggests that effective use of person–group fit will create
both more cohesive work units and more effectively functioning work units. It proposes ways to make valid and
reliable assessments of person–group fit that could be used to minimize bias in the selection process.
Finally, it addresses several implications of using the person–group fit paradigm for human resource
management practice. © 2001 John Wiley & Sons, Inc.
Influence of cigarette smoking on prepulse inhibition of the acoustic startle response in schizophrenia
Authors: Kumari Veena , Soni William , Sharma Tonmoy
Published: August 2002

The prevalence of tobacco smoking is known to be higher in patients with schizophrenia than other psychiatric disorders and general population. These patients also show reduced prepulse inhibition (PPI) of the startle response. PPI refers to a reduction in response to a strong startling stimulus if preceded shortly by a stimulus of sub‐threshold intensity. PPI is thought of as an objective index of sensorimotor gating. Nicotine administered subcutaneously or via cigarette smoking enhances PPI in healthy human beings. It also enhances PPI at low, but not high, doses in the rat. We examined the influence of smoking on PPI of the acoustic startle response in 46 male patients with chronic schizophrenia. In a naturalistic design, patients (n = 9) who smoked a cigarette less than 10 min prior to being tested on PPI were compared with other smoking (n = 23) and non‐smoking patients (n = 14). We found that the group of patients who smoked a cigarette prior to being tested had significantly greater PPI than other two groups. These observations suggest a PPI‐enhancing effect of cigarette smoking on PPI in patents with schizophrenia. Higher prevalence of cigarette smoking in schizophrenic patients may reflect an attempt to improve sensorimotor gating deficits. Copyright © 2001 John Wiley & Sons, Ltd.
The effects of caffeine on simulated driving, subjective alertness and sustained attention
Authors: Brice Carolyn , Smith Andrew
Published: August 2002

There is evidence that caffeine increases alertness and reduces fatigue. This may be especially so in low arousal situations (e.g. working at night or for prolonged hours). Caffeine has also been found to improve performance on vigilance tasks and simple tasks requiring sustained response. Again, these effects are often clearest when alertness is reduced, although there is evidence that benefits may still occur when the individual is unimpaired. Most studies to date have investigated the behavioural effects of caffeine in laboratory experiments using artificial tasks. In the current study 3 mg/kg caffeine was found to improve steering accuracy in a 1 h simulated drive. Measures of mood and performance on a sustained attention task also showed the benefits of caffeine. These findings suggest that laboratory results reflect a general benefit of caffeine that may also be observed in real‐life situations. Other evidence examining the effects of caffeine on performance efficiency over the working day has shown the benefits of caffeine consumption on measures of sustained attention and alertness. This study also provided evidence suggesting that caffeine is often consumed when alertness is low to maximise alertness and performance efficiency. The implications of these findings for road safety are also considered. Copyright © 2001 John Wiley & Sons, Ltd.
Prospective memory, everyday cognitive failure and central executive function in recreational users of Ecstasy
Authors: Heffernan T. M. , Jarvis H. , Rodgers J. , Scholey A. B. , Ling J.
Published: August 2002

Chronic use of MDMA (3,4‐methylenedioxymethamphetamine), or Ecstasy, is believed to lead to impaired psychological performance, including well‐documented decrements in laboratory and field tests of retrospective memory. Less is known about the impact of Ecstasy on aspects of ‘everyday’ memory, despite obvious concerns about such effects. The three studies reported here focused on the impact of chronic Ecstasy use on prospective memory (PM), associated central executive function and other aspects of day‐to‐day cognition. In study 1 46 regular Ecstasy users were compared with 46 Ecstasy‐free controls using the Prospective Memory Questionnaire (PMQ). Ecstasy users reported significantly more errors in PM (remembering to do something in the future); these findings persisted after controlling for other drug use and the number of strategies used to aid memory. No difference was found between representative subgroups on the Lies Scale of the Eysenck Personality Questionnaire. In study 2 a different group of 30 regular Ecstasy users and 37 Ecstasy‐free controls was assessed on the PMQ and on a central executive task comprising verbal fluency measures. The results confirmed the significant impairments in long‐ and short‐term PM and revealed corresponding impairments in verbal fluency. In study 3 15 Ecstasy users, 15 cannabis users and 15 non‐drug users were assessed using the Cognitive Failures Questionnaire, which requires participants to provide ratings of the frequency of various day‐to‐day cognitive slips. The results indicate that the Ecstasy users did not perceive their general cognitive performance to be worse than that of controls. Taken together, these results suggest that Ecstasy users have impaired PM that cannot be explained by an increased propensity to exaggerate cognitive failures. These may be attributable, in part, to central executive deficits that are due to frontal lobe damage associated with Ecstasy use. Copyright © 2001 John Wiley & Sons, Ltd.
Minor and trace element export from a glacierized Alpine headwater catchment (Haut Glacier d'Arolla, Switzerland)
Authors: Mitchell Andrew , Brown Giles H. , Fuge Ron
Published: August 2002

Major ion concentrations in meltwaters draining glacial environments have been widely reported. However, concentrations of minor and trace elements have received scant attention. This study presents trace and minor element variations in bulk meltwaters draining Haut Glacier d'Arolla (Switzerland) based on twice‐daily sampling throughout the 1999 ablation season, which represents the most detailed meltwater quality dataset to date. In order to assess the mode of export from the catchment, these elements are partitioned into (i) ‘dissolved’ and (ii) ‘particulate‐associated’ minor and trace element components.

A computer‐based speciation model (PHREEQCi) was applied to the bulk meltwater data, suggesting that Ba, Be, Cd, Cu, Li, Rb and Sr exist primarily as mobile monovalent or divalent dissolved cations, which may be involved in interactions with suspended sediment surfaces. Conversely, the model predicts the precipitation of Fe, Al, Mn and Cr (oxi)hydroxides, suggesting these species may be predominantly transported as colloids, which may remove other minor and trace elements from solution by co‐precipitation reactions.

Laboratory leaching experiments on suspended sediments and fresh rock powder suggests that minor and trace element concentrations may also be influenced by (oxy)hydroxide precipitation and adsorption–desorption reactions with suspended sediment surfaces. The quantity and transport mode of trace and minor elements may influence their bioavailability downstream of glacierized headwater catchments. Further, the enrichment of many dissolved minor and trace elements in meltwaters compared with world stream‐waters, coupled with the timing of water and sediment delivery during the summer months, may have implications for downstream aquatic environments. Copyright © 2001 John Wiley & Sons, Ltd.
Hydrological and erosional response to natural rainfall in a semi‐arid area of south‐east Spain
Authors: Martinez‐Mena M. , Castillo V. , Albaladejo J.
Published: August 2002

A better knowledge of soil erosion by water is essential for planning effective soil and water conservation practices in semi‐arid Mediterranean environments. The special climatic and hydrological characteristics of these areas, however, make accurate soil loss predictions difficult, particularly in the absence of minimal data. Two zero‐order experimental microcatchments (328–759 m2), representative of an extensive semi‐arid watershed with a high potential erosion risk in the south‐east of Spain, were selected and monitored for 3 years (1991–93) in order to provide information on the hydrological and erosional response. A pluviogram and hydrograph recorded data at 1‐min intervals during each storm, after which the soil loss was collected and the particle size of the sediment was analysed. Runoff coefficients of about 9% and soil losses of between 84·83 and 298·9 g m−2 year−1 were observed in the area. Rapid response times (geometric mean values lower than 2 h) and low runoff thresholds (mean values between 3·5 to 5·9 mm) were the norm in the experimental areas. A rain intensity of over 15 mm h−1 was considered as ‘erosive rainfall’ in these areas because of the total soil loss and the transport capacity of the overland flow. Differences in pore‐size distribution explained the different hydrological responses observed between areas. The erosional response was more complex and basically seemed to be determined by soil aggregate stability and topographical properties. A greater proportion of finer particles in the eroded material than in the soil matrix indicated selective erosion and the transport of finer material. Copyright © 2001 John Wiley & Sons, Ltd.
Seasonal evolution of meltwater generation, storage and discharge at a non‐temperate glacier in Svalbard
Authors: Hodgkins Richard
Published: August 2002

In glacierized catchments, meteorological inputs driving surface melting are translated into runoff outputs mediated by the glacier hydrological system: analysis of the relationship between meteorology and diurnal and seasonal patterns of runoff should reflect the functioning of that system, with the role of meltwater storage likely to be of particular importance. Daily meltwater storage is determined for a glacier at 78 °N in the Svalbard archipelago, by comparing inputs calculated from a surface energy balance model with measured outputs (proglacial discharge). Solar radiation, air temperature, wind speed and proglacial discharge are then analysed by regression and time‐series methods, in order to assess the meteorology–discharge relationship and its variation at diurnal and seasonal time‐scales. The recorded discharge time‐series can be divided into two contrasting intervals: up to early August, proglacial discharge was high and variable, mean hydrographs showed little indication of diurnal cycling, ARIMA models of discharge indicated a non‐seasonal, moving‐average generating process, and there was a net loss of meltwater from storage; from early August, proglacial discharge was low and relatively invariable, but with clearer diurnal cycles, regression models of discharge showed substantially improved correlations with air temperature and solar radiation, ARIMA models indicated a non‐seasonal, autoregressive generating process, and eventually a seasonal component, and there was a net gain in meltwater storage. The transition between the two periods is brief compared with the duration of the melt season. The runoff response to meteorology therefore lacks the strongly progressive element previously identified in mid‐latitude glacierized catchments. In particular, the glacier hydrological system only appears responsive to diurnal forcing following the depletion of the seasonal snowpack meltwater store. Copyright © 2001 John Wiley & Sons, Ltd.
A bivariate gamma distribution for use in multivariate flood frequency analysis
Authors: Yue Sheng
Published: August 2002

A gamma distribution is one of the most frequently selected distribution types for hydrological frequency analysis. The bivariate gamma distribution with gamma marginals may be useful for analysing multivariate hydrological events. This study investigates the applicability of a bivariate gamma model with five parameters for describing the joint probability behavior of multivariate flood events. The parameters are proposed to be estimated from the marginal distributions by the method of moments. The joint distribution, the conditional distribution, and the associated return periods are derived from marginals. The usefulness of the model is demonstrated by representing the joint probabilistic behaviour between correlated flood peak and flood volume and between correlated flood volume and flood duration in the Madawask River basin in the province of Quebec, Canada. Copyright © 2001 John Wiley & Sons, Ltd.
Soil partitioning and surface store controls on spring runoff from a boreal forest peatland basin in north‐central Manitoba, Canada
Authors: Metcalfe R. A. , Buttle J. M.
Published: August 2002

The mid‐ to high‐boreal forest in Canada occupies the discontinuous permafrost zone, and is often underlain by glaciolacustrine sediments mantled by a highly porous organic mat. The result is a poorly drained landscape dominated by wetlands. Frost‐table dynamics and surface storage conditions help to control runoff contributions from various landscape elements, hydrological linkages between these elements, and basin streamflow during spring snowmelt. Runoff components and pathways in a forested peatland basin were assessed during two spring snowmelts with contrasting input and basin conditions. Runoff from relatively intense melt (up to 16 mm day−1) on slopes with limited soil thawing combined with large pre‐melt storage in surface depressions to produce high flows composed primarily of meltwater (78% of the 0·29 m3 s−1 peak discharge) routed over wetland surfaces and through permeable upper peat layers. Melt intensity was less in the subsequent year (maximum of 10 mm day−1) and active layer development was relatively greater (0·2 m deeper at the end of spring melt), resulting in less slope runoff. Coupling of reduced slope contributions with lower storage levels in basin wetlands led to relatively subdued streamflows dominated by older water (73% of the 0·09 m3 s−1 peak discharge) routed through less‐permeable deeper peat layers and mineral soil. Interannual differences in runoff conditions provide important insight for the development of distributed hydrological models for boreal forest basins and into potential influences on biogeochemical cycling in this landscape under a warming climate. Copyright © 2001 John Wiley & Sons, Ltd.
A comparison between measured and modelled open water evaporation from a reservoir in south‐east England
Authors: Finch J. W.
Published: August 2002

Estimates of evaporation from large open water bodies are required for a variety of purposes in water resource management. The equilibrium temperature approach provides a means of taking into account the heat storage in the water body. The evaporation predicted by a model based on this method is tested against measured evaporation from a reservoir at Kempton Park, UK. The evaporation and water temperature predicted by the model are in good agreement with the measurements. The mean annual evaporation is predicted to almost the same accuracy as the measurements. Estimates of the monthly predicted evaporation have root mean square errors about three times those of the measurements. The error in the mean annual evaporation estimated without taking the heat storage into account is 16%. Copyright © 2001 John Wiley & Sons, Ltd.
The benthic macroinvertebrate community of the upper reaches of an Australian estuary that undergoes marked seasonal changes in hydrology
Authors: Kanandjembo A. N. , Platell M. E. , Potter I. C.
Published: August 2002

Benthic macroinvertebrates were collected from the substrata of nearshore, shallow waters (depths <1 m) and offshore, deeper waters (depths 2·5–5 m) of three regions in the saline lower reaches of the tributary rivers that comprise the upper Swan Estuary in each season between winter 1995 and autumn 1997. Freshwater discharge in the two tributary rivers varied markedly during both years and consequently salinities in the upper estuary ranged from <1‰ in winter to >30‰ in autumn. The most abundant species, the galeommatid bivalve Arthritica semen, contributed >25% to the total numbers of macroinvertebrates in both shallow and deeper waters. The continuous reproduction, rapid growth, short life cycle and tolerance to a wide range of salinities, that characterize this species, represent ideal adaptations for life in a seasonally very variable environment. The overall number of species and density of benthic macroinvertebrates were typically greater in shallow than deeper waters. Species composition also differed significantly between water depths. The nereidid polychaete Ceratonereis aequisetis and mytilid bivalve Xenostrobus securis, which feed on plant material, were relatively far more abundant in shallow than deeper waters, whereas the reverse was true for the spionid polychaete Prionospio cirrifera and sabellid polychaete Desdemona ornata, which feed on the detrital material that settles out in deep waters. Heavy freshwater discharge in winter 1996 was accompanied by very marked changes in the richness, density and composition of species in shallow waters, but not in those of deeper waters where scouring would have been less pronounced. The species compositions in both the shallow and deeper waters of each region usually differed significantly among the seasons of each year and between the corresponding seasons in the different years. Region within the estuary had little or no influence on the species richness, density and faunal composition of benthic macroinvertebrates, even though the regions were located in two different tributary rivers. The above results demonstrate that, within each region, certain species were particularly successful in the first year, while others were more abundant in the second year, which in turn suggests that the benthic macroinvertebrate fauna of each region is responding to the same fine‐scale differences between environmental conditions in the two years. Copyright © 2001 John Wiley & Sons, Ltd.
The impact of climate change on seasonal floods of a southern Quebec River Basin
Authors: Roy Luc , Leconte Robert , Brissette François P. , Marche Claude
Published: August 2002

Global warming predicted by general circulation models (GCM) is now a more and more generally agreed upon effect. The impact of climate change on summer and fall flooding on the Châteauguay River Basin (2500 km2), located at the southern end of the Quebec province (Canada), was investigated using results from the Canadian GCM (CGCM1) and a coupled hydrology–hydraulics model of the basin. Three 20‐year periods, corresponding to 1975–1995, 2020–2040 and 2080–2100, were used for the analysis. For each period, 24‐h precipitation depths corresponding to the 20 and 100‐year return periods were determined from a frequency analysis of the summer–fall maximum 24‐h precipitations using a general extreme value frequency distribution. 24‐h rainfall hyetographs were generated using region‐specific cumulative distributions provided by the Canadian Atmospheric Environment Service. These hyetographs were then used as inputs to the hydrology–hydraulics model to simulate hydrographs, maximum discharge and maximum water levels at two sections of the river. Results indicate potentially very serious increases in the volume of runoff, maximum discharge and water level with future climate change scenarios. The changes get more drastic as longer return periods are considered. Increases of up to 250% of the maximum water discharge are encountered and water levels are significantly higher than the current flood levels. If realistic, these scenarios indicate that important decisions will have to be taken to alleviate future increases in flooding damages in what is already a flood prone river. Copyright © 2001 John Wiley & Sons, Ltd.
Hydraulic and mechanical properties of glacial sediments beneath Unteraargletscher, Switzerland: implications for glacier basal motion
Authors: Fischer Urs H. , Porter Philip R. , Schuler Thomas , Evans Andrew J. , Gudmundsson G. Hilmar
Published: August 2002

The force on a ‘ploughmeter’ and subglacial water pressure have been measured in the same borehole at Unteraargletscher, Switzerland, in order to investigate ice–sediment coupling and the motion at the base of a soft‐bedded glacier. A strong inverse correlation of the recorded pressure and force fluctuations, in conjunction with a significant time lag between the two signals, suggests that pore‐water pressures directly affect the strength of the subglacial sediment. The lag is interpreted to reflect the time required for the water‐pressure wave to propagate through the pores of the sediment to the depth of the ploughmeter. Analysis of the propagation velocity of this pressure wave yielded an estimate of the hydraulic diffusivity, a key parameter necessary to characterize transient pore‐water flow. Furthermore, the inferred inverse relationship between pore‐water pressure and sediment strength implies that Coulomb‐plastic deformation is an appropriate rheological model for the sediment underlying Unteraargletscher. However, the sediment strength as derived from the ploughmeter data was found to be one order of magnitude smaller than that calculated for a Coulomb‐frictional material using the water‐pressure measurements. This significant discrepancy might result from pore‐water pressures in excess of hydrostatic down‐glacier from the ploughmeter. As the ploughmeter is dragged through the sediment, sediment is compressed. If the rate of this compression is large relative to the rate at which pore water can drain away, excess pore‐water pressures will develop that have the potential to weaken the sediment. The same process could lead to highly fluid sediment down‐glacier from clasts that protrude into the glacier sole and thus would otherwise provide the roughness to couple the glacier to its bed (Iverson, 1999). Rapidly sliding glaciers overlying sediments might therefore move predominantly by ‘ploughing’, which tends to focus basal motion near the glacier sole rather than at depth in the bed. Copyright © 2001 John Wiley & Sons, Ltd.
Spatial and temporal effects of wildfire on the hydrology of a steep rangeland watershed
Authors: Pierson Frederick B. , Robichaud Peter R. , Spaeth Kenneth E.
Published: August 2002

Wildfire is a major ecological process and management issue on western rangelands. The impacts of wildfire on hydrologic processes such as infiltration, runoff, and erosion are not well understood. Small‐plot rainfall simulation methods were applied in a rangeland wildfire setting to determine post‐fire hydrologic response. Infiltration and interrill erosion processes were measured immediately post‐fire and one year following the 1999 34 400 ha Denio fire in northwestern Nevada. Plot‐scale spatial and temporal variability in fire impacts was compared with adjacent unburned areas. An index of water repellency was derived and used to quantify the influence of water‐repellent soil conditions on infiltration. Results indicate the impact of the fire on infiltration was localized primarily on coppice microsites directly under shrubs characterized by high surface litter accumulations. Coppice microsites had very uniform fire‐induced soil water repellency with 29 of 30 plots exhibiting at least a 10% reduction in initial infiltration with an average 28% reduction. Cumulative erosion was nearly four times higher on burned coppices compared with unburned coppices. The impact of the fire on infiltration and erosion was reduced, but still evident, 1 year after fire. Significant temporal variability in infiltration between years was observed on both burned and unburned areas, complicating the interpretation of fire impacts and hydrologic recovery following wildfire. Published in 2001 John Wiley & Sons, Ltd.
Post‐fire, rainfall intensity–peak discharge relations for three mountainous watersheds in the western USA
Authors: Moody John A. , Martin Deborah A.
Published: August 2002

Wildfire alters the hydrologic response of watersheds, including the peak discharges resulting from subsequent rainfall. Improving predictions of the magnitude of flooding that follows wildfire is needed because of the increase in human population at risk in the wildland–urban interface. Because this wildland–urban interface is typically in mountainous terrain, we investigated rainfall‐runoff relations by measuring the maximum 30 min rainfall intensity and the unit‐area peak discharge (peak discharge divided by the area burned) in three mountainous watersheds (17–26·8 km2) after a wildfire.

We found rainfall‐runoff relations that relate the unit‐area peak discharges to the maximum 30 min rainfall intensities by a power law. These rainfall‐runoff relations appear to have a threshold value for the maximum 30 min rainfall intensity (around 10 mm h−1) such that, above this threshold, the magnitude of the flood peaks increases more rapidly with increases in intensity. This rainfall intensity could be used to set threshold limits in rain gauges that are part of an early‐warning flood system after wildfire. The maximum unit‐area peak discharges from these three burned watersheds ranged from 3·2 to 50 m3 s−1 km−2. These values could provide initial estimates of the upper limits of runoff that can be used to predict floods after wildfires in mountainous terrain. Published in 2001 John Wiley & Sons, Ltd.
A process for fire‐related debris flow initiation, Cerro Grande fire, New Mexico
Authors: Cannon Susan H. , Bigio Erica R. , Mine Edouard
Published: August 2002

In this study we examine factors that pertain to the generation of debris flows from a basin recently burned by wildfire. Throughout the summer 2000 thunderstorm season, we monitored rain gauges, channel cross‐sections, hillslope transects, and nine sediment‐runoff traps deployed in a steep, 0·15 km2 basin burned by the May 2000 Cerro Grande fire in New Mexico. Debris flows were triggered in the monitored basin during a rainstorm on July 16, 2000, in response to a maximum 30 min rainfall intensity of 31 mm h−1 (return period of approximately 2 years). Eleven other storms occurred before and after the July storm; these storms resulted in significant runoff, but did not generate debris flows.

The debris flows generated by the July 16 storm initiated on a broad, open hillslope as levee‐lined rills. The levees were composed of gravel‐ and cobble‐sized material supported by an abundant fine‐grained matrix. Debris‐flow deposits were observed only on the hillslopes and in the first and second‐order drainages of the monitored basin. No significant amounts of channel incision were measured following the passage of the debris flows, indicating that most of the material in the flows originated from the hillslopes.

Sediment‐runoff concentrations of between 0·23 and 0·81 kg l−1 (with a mean of 0·42 kg l−1) were measured from the hillslope traps following the debris‐flow‐producing storm. These concentrations, however, were not unique to the July 16 storm. The materials entrained by the July 16 storm contained a higher proportion of silt‐ plus clay‐sized materials in the <2 mm fraction than the materials collected from storms that produced comparable sediment‐runoff concentrations but not debris flows. The difference in materials demonstrates the critical role of the availability of fine‐grained wood ash mantling the hillslopes in the runoff‐dominated generation of post‐wildfire debris flows. The highest sediment‐runoff concentrations, again not unique to debris‐flow production, were produced from maximum 30 min rainfall intensities greater than 20 mm h−1. Copyright © 2001 John Wiley & Sons, Ltd.
Role of stromal collagen in immunomodulation and prognosis of advanced gastric carcinoma
Authors: Ohno Satoshi , Tachibana Mitsuo , Fujii Toshiyuki , Ueda Shuhei , Kubota Hirofumi , Nagasue Naofumi
Published: August 2002

Although several hypotheses have been proposed explaining the mechanisms of the immune‐privileged status of malignant tumors, the exact pathway is yet to be explored. Tumor stroma plays a vital role in the prognosis of cancer patients; however, the immunomodulatory impact of gastric cancer stroma has not been reported. We have evaluated the amount of stromal collagen and its impact on the infiltration of immune‐competent cells into the tumor cell nest in gastric carcinoma. Tissue specimens from 84 advanced gastric carcinoma patients who had undergone a curative resection were evaluated for host immune status (CD8+ T cells), tumor stromal reaction (AZAN staining), tumor Fas ligand expression and incidence of tumor cell apoptosis (by TUNEL). The number of apoptotic tumor cells (apoptotic index [AI]) increased proportionally with an increase in the number of CD8+ T cells within the cancer cell nest (nest CD8) (p= 0.0001). Nest CD8 was inversely correlated with the amount of stromal collagen (p< 0.0001). Nest CD8 and AI became independent predictors of patient survival (p= 0.0023 andp= 0.044, respectively) in Cox's multivariate analysis. The amount of stromal collagen was found to be a significant predictor of disease relapse in univariate analysis (p= 0.0010) but not in multivariate analysis (p= 0.4729). In conclusion, increased nest CD8 produced a survival advantage by inducing tumor cell apoptosis in gastric carcinoma patients. Increased tumor stromal collagen worked as a barrier for CD8+ T‐cell infiltration and might be one of the mechanisms of tumor escape from the host immune attack. © 2001 Wiley‐Liss, Inc.
Transcriptional inactivation of TP73 expression in oligodendroglial tumors
Authors: Dong Shumin , Pang Jesse Chung‐sean , Hu Jie , Zhou Liang‐fu , Ng Ho‐keung
Published: August 2002

The TP73 gene, located on chromosome 1p36.3, encodes a product that shares significant structural homology with the tumor suppressor TP53. The aim of this study was to investigate whether TP73 is involved in the development of oligodendroglial tumors, which frequently carry deletions involving 1p36.3. Semi‐quantitative reverse transcription‐polymerase chain reaction was used to determine TP73 transcript levels. Ten of 24 (42%) tumors showed negligible to more than 5‐fold reduction in TP73 expression when compared to normal brain level. To identify potential mechanisms that may modulate TP73 transcription in oligodendroglial tumors, we performed mutation analysis on the TP73 gene. No somatic mutations were however detected in the gene sequence. We then evaluated the possible involvement of epigenetic change in TP73 expression. Bisulfite genomic sequencing detected aberrant hypermethylation at the 5′ region upstream and including the first exon of the TP73 gene in 17 of 44 (39%) oligodendroglial tumors, whereas normal brain tissues showed no methylation in the same region examined. Moreover, 6 of 10 (60%) tumors with negligible or decreased levels of TP73 transcripts were methylation‐positive. In conclusion, our results showed that inactivation of TP73 occurs at the transcriptional level and is associated with promotor hypermethylation. Loss of or reduced TP73 transcript expression may contribute to the tumorigenesis of oligodendroglial tumors. © 2002 Wiley‐Liss, Inc.
Inhibition of tumor growth by systemic treatment with thrombospondin‐1 peptide mimetics
Authors: Reiher Frank K. , Volpert Olga V. , Jimenez Benilde , Crawford Susan E. , Dinney Colin P. , Henkin Jack , Haviv Fortuna , Bouck Noel P. , Campbell Steven C.
Published: August 2002

Many normal human cells produce thrombospondin‐1 (TSP‐1), a potent antiangiogenic protein that promotes vascular quiescence. In various organ systems, including the brain, breast and bladder and in fibroblasts, TSP‐1 secretion is reduced during tumorigenesis, thereby allowing induction of the vigorous neovascularization required for tumor growth and metastasis. Full‐length and short TSP‐1–derived peptides inhibit angiogenesis by inducing endothelial cell apoptosis and thus disrupting the vasculature of the growing tumor. CD36 expressed on the surface of endothelial cells functions as the primary antiangiogenic receptor for TSP‐1. A D‐isoleucyl enantiomer of a TSP‐1 heptapeptide specifically inhibits the proliferation and migration of capillary endothelial cells. DI‐TSP, an approximately 1 kDa capped version of this peptide, is also antiangiogenic in vitro, with a specific activity approaching that of the 450 kDa parental molecule. Here, we show that DI‐TSP delivered systemically dose‐dependently inhibits the growth of murine melanoma metastases in syngeneic animals and that its more soluble isomer, DI‐TSPa, similarly blocks the progression of primary human bladder tumors in an orthotopic model in immune‐deficient mice. Like intact TSP‐1, these peptide mimetics had no effect on cancer cells growing in vitro but markedly suppressed the growth of endothelial cells by inducing receptor‐dependent apoptosis. Antibodies raised against CD36 blocked the ability of peptides to induce apoptosis in endothelial cells but had no effect on tumor necrosis factor‐α–induced apoptosis. In vivo, the peptide mimetics were associated with a significantly reduced microvessel density and increased apoptotic indices in both the endothelial and tumor cell compartments. Such short peptides targeted to a specific antiangiogenic receptor, potent and easy to synthesize, show great promise as lead compounds in clinical antiangiogenic strategies. © 2002 Wiley‐Liss, Inc.
Effect of highly active antiretroviral therapy on survival among HIV‐infected men with Kaposi sarcoma or non‐Hodgkin lymphoma
Authors: Tam Henry K. , Zhang Zuo‐Feng , Jacobson Lisa P. , Margolick Joseph B. , Chmiel Joan S. , Rinaldo Charles , Detels Roger
Published: August 2002

The effect of highly active antiretroviral therapy (HAART) on survival in HIV‐infected patients with Kaposi sarcoma (KS) or non‐Hodgkin lymphoma (NHL) is unknown. Our study examines survival after HAART for these 2 malignancies. Analyses were performed using data from 387 HIV‐infected men in the Multicenter AIDS Cohort Study (MACS) after a diagnosis of either KS or NHL in 1990–99. Potential prognostic factors, including HAART, were evaluated in univariate analyses using Kaplan‐Meier survival curves and log‐rank tests. Multivariate survival analyses were conducted using Cox's time‐dependent proportional hazards models, adjusting for CD4+cell levels at the time of cancer diagnosis and other covariates. Forty‐three of 287 KS patients (15%) and 13 of 100 NHL patients (13%) had been treated with HAART. HAART treatment was associated with improved survival for KS and NHL patients (log‐rankp= 0.0001 for each group). In multivariate analyses, HAART was associated with an 81% reduced risk of death among KS patients [relative hazard (RH) 0.19, 95% confidence limits (CL) (0.08, 0.45)], compared to those not exposed to HAART and an 84% reduced risk [RH 0.16, 95% CL (0.04, 0.64)] among NHL patients. Relative hazards estimates were similar for those with HAART initiation before and after NHL diagnosis. The use of HAART prolongs overall survival among HIV‐positive men diagnosed with KS and NHL. HAART appears to be effective in improving survival even when initiated after the diagnosis of NHL and KS. © 2002 Wiley‐Liss, Inc.
Case‐control study evaluating the homogeneity and heterogeneity of risk factors between sinonasal and nasopharyngeal cancers
Authors: Zhu Kangmin , Levine Robert S. , Brann Edward A. , Hall H. Irene , Caplan Lee S. , Gnepp Douglas R.
Published: August 2002

Sinonasal cancer and nasopharyngeal cancer may share some risk factors because both are located within the upper aerodigestive tract. They may also have different etiological profiles because of anatomic or pathologic differences. However, the similarities and differences in risk factors have rarely been studied within the same population. We assessed the risk factor profiles of sinonasal and nasopharyngeal cancers, using data from a case‐control study. The 2 case groups consisted of men aged 31–59 and diagnosed pathologically with sinonasal cancer (n=70) and nasopharyngeal cancer (n=113), respectively. Controls were men without these cancers and selected from the same areas (n=1910). Logistic regression analysis showed that smoking was a risk factor for both sinonasal [odds ratio (OR)=2.5, 95% confidence interval (CI) 1.1–5.4] and nasopharyngeal cancer (OR=1.8, 95%CI 1.1–3.0). However, ever use of barbiturates without a prescription (OR=4.9, 95%CI 1.7–13.8), working with or around cutting oils on a job (OR=1.9, 95%CI 1.1–3.1) and ever having had sinus infections (OR=2.3, 95%CI 1.1–4.6) were associated with nasopharyngeal cancer only. Having received blood products other than a transfusion (OR=9.1, 95%CI 2.2–37.4) and exposure to a pesticide containing 2,4,5‐T (OR=5.9, 95%CI 1.5–23.7) were related to sinonasal cancer only. When data analyses were confined to squamous cell type, smoking and exposure to chlorophenols were related to squamous cell tumors at both sites. However, use of barbiturates and sinus problems other than infection only increased the risk of nasopharyngeal carcinoma. Our study suggests that except for smoking and chlorophenol exposure, which are associated with both sites, the risk factor profiles may differ between sinonasal and nasopharyngeal cancers. © 2002 Wiley‐Liss, Inc.
Detecting multiple objects under partial occlusion by integrating classification and tracking approaches
Authors: Foresti G.L.
Published: August 2002

A visual‐based framework for detecting in real time multiple objects in real outdoor scenes is presented. The main novelty of the system is its capability to reduce the problems of partial occlusions and/or overlaps that occur very commonly in real scenes containing multiple moving objects. Overlaps and occlusions are dealt with by integrating classification and tracking procedures into a data‐fusion distributed sensory network. Neural tree‐based networks are applied to distinguish among isolated objects and groups of objects on the image plane. Extended Kalman filters are applied to estimate the number of objects in the scene, their position, and the related motion parameters. Experimental results on complex outdoor scenes with multiple moving objects are presented. © 2001 John Wiley & Sons, Inc. Int J Imaging Syst Technol, 11, 263–276, 2000
Children prenatally exposed to substances: Gender‐related differences in outcome from infancy to 3 years of age
Authors: Moe Vibeke , Slinning Kari
Published: August 2002

A group of 78 children with polysubstance exposure in utero and a comparison group of 58 children with no known risk status were followed from infancy to age 3 years. Sixty‐six children (84.6%) in the exposed group were taken into custody, and were either placed in foster homes or adopted. The foster parents were specially recruited to provide care to infants at risk. The substance‐exposed group exhibited significantly lower birthweight, gestational age, and head circumference than the comparison group. The perinatal data demonstrated no gender differences. The children were assessed on the Bayley‐II Scales of Infant Development at 1, 2, and 3 years of age. The results yielded a significant group by gender interaction on the Bayley‐II MDI. The boys, but not the girls who had been prenatally exposed to polydrugs, alcohol, and tobacco earned significantly lower MDI scores at 1, 2, and 3 years of age than the comparison group at the corresponding ages. The gender differences were still statistically significant when controlling for the effects of prematurity and the caregivers' socioeconomic status. This suggests a special vulnerability in prenatally substance‐exposed boys, perhaps because of cumulative risk. However, this group of exposed children did show a developmental catch‐up across the first 3 years of life. We suggest that the optimized caregiving environment had a buffering effect, and may have compensated for initial developmental lags in this group of children. ©2001 Michigan Association for Infant Mental Health.
Daily exchange rate behaviour and hedging of currency risk
Authors: Bos Charles S. , Mahieu Ronald J. , Van Dijk Herman K.
Published: August 2002

We construct models which enable a decision maker to analyse the implications of typical time series patterns of daily exchange rates for currency risk management. Our approach is Bayesian where extensive use is made of Markov chain Monte Carlo methods. The effects of several model characteristics (unit roots, GARCH, stochastic volatility, heavy‐tailed disturbance densities) are investigated in relation to the hedging strategies. Consequently, we can make a distinction between statistical relevance of model specifications and the economic consequences from a risk management point of view. We compute payoffs and utilities from several alternative hedge strategies. The results indicate that modelling time‐varying features of exchange rate returns may lead to improved hedge behaviour within currency overlay management. Copyright © 2000 John Wiley & Sons, Ltd.
Model uncertainty in cross‐country growth regressions
Authors: Fernández Carmen , Ley Eduardo , Steel Mark F. J.
Published: August 2002

We investigate the issue of model uncertainty in cross‐country growth regressions using Bayesian Model Averaging (BMA). We find that the posterior probability is spread widely among many models, suggesting the superiority of BMA over choosing any single model. Out‐of‐sample predictive results support this claim. In contrast to Levine and Renelt (1992), our results broadly support the more ‘optimistic’ conclusion of Sala‐i‐Martin (1997b), namely that some variables are important regressors for explaining cross‐country growth patterns. However, care should be taken in the methodology employed. The approach proposed here is firmly grounded in statistical theory and immediately leads to posterior and predictive inference. Copyright © 2001 John Wiley & Sons, Ltd.
Improved erythrocyte lysis assay in microtitre plates for sensitive detection and efficient measurement of haemolytic compounds from ichthyotoxic algae
Authors: Eschbach Erik , Scharsack Jörn P. , John Uwe , Medlin Linda K.
Published: August 2002

Haemolytic substances produced by ichthyotoxic algae often are unknown in molecular structure or specific mechanism of toxicity. Detection and quantification of such substances are dependent on bioassays, using markers that are sensitive for haemolytic impairment and generation of a recordable response. The erythrocyte lysis assay (ELA) represents an advantageous bioassay in this respect, because the lytic response can be measured photometrically by the amount of released haemoglobin. The aim of the present study was to establish an improved assay based on the ELA principle, for sensitive determination of haemolytic substances of microalgae and for high sample throughput. For this purpose we adapted the ELA to a 96‐well microtitre plate format, which significantly reduced the sample volumes and allowed rapid processing of samples. Further improvement was achieved by measuring absorption of lysed erythrocytes at 414 nm, which significantly increased the sensitivity of the ELA compared to the measurements at 540 nm that are usually applied in this type of assay. Using carp (Cyprinus carpio) erythrocytes it was possible to detect haemolysis induced by 4 µg ml−1 of saponin and as little as two haemolytic Alexandrium tamarense cells. It is suggested that this improved ELA in microtitre plates be used as a low‐cost monitoring tool for detection and analysis of potential harmful algae. Furthermore, this ELA can be useful as a sensitive screening system for substances of pharmacological interest, e.g. selectively acting cytolytic antibiotics. Copyright © 2001 John Wiley & Sons, Ltd.