bluuebunny/crossref_metadata_2025 huggingface dataset:
Calculation of crystal truncation rod structure factors for arbitrary rational surface terminations
Authors: Trainor Thomas P. , Eng Peter J. , Robinson Ian K.
Published: November 2002

The technique of crystal truncation rod (CTR) diffraction is widely used for studying the structure of crystalline surfaces and interfaces. The theory and experimental details of the technique are well established; however, published methods for structure-factor calculations are typically based on a simple surface cell geometry. A method is presented for determining a surface coordinate system which results in a reciprocal lattice that is simply defined in terms of the surface termination. Based on this surface coordinate system, a general formalism for the calculation of CTR structure factors is re-derived, which may be easily applied to any surface that can be represented as a rational plane of a bulk crystal system.
Evaluation of a culturally appropriate smoking cessation intervention for Latinos
Authors: Woodruff S I , Talavera G A , Elder J P
Published: November 2002

Background:Many believe that smoking cessation programmes for Latinos should be tailored to the values and beliefs of the culture. However, randomised studies of culturally appropriate smoking cessation interventions with Latinos are rare.

Methods:Latino smokers (n = 313) were randomised to an intervention condition or a comparison group. The intervention was a three month programme based on social cognitive constructs and delivered in the smoker’s home by trained lay health advisors, orpromotores. Comparison group participants were referred to the California Smoker’s Helpline in Spanish. Predictors of abstinence among all participants also were examined.

Results:About one week post-intervention, validated (carbon monoxide) past week abstinence rates were more than twice as high in the intervention group (20.5%) than in the comparison (8.7%) (p ≤ 0.005). The pattern of results held for self reported abstinence, and after recoding dropouts to non-abstinence. The primary predictor of abstinence was number of cigarettes smoked per day at baseline, a common measure of addiction.

Conclusions:The culturally appropriate intervention facilitated abstinence in Latino smokers, at least in the short term. Strengths and weaknesses of the study are discussed.
Mentholated cigarettes and smoking habits in whites and blacks
Authors: Muscat J E , Richie J P , Stellman S D
Published: November 2002

Objective:To determine if cigarette mentholation is associated with the frequency of smoking and with quitting, and whether mentholation explains racial differences in these two smoking behaviours.

Design:Cross sectional analysis of case–control data on smoking and lung cancer.

Subjects:Limited to 19 545 current and former cigarette smokers.

Main outcome measures:Smoking > 20 cigarettes per day (cpd) versus ≤ 20 cpd, and continued smoking versus quit smoking.

Results:Among blacks, the prevalence odds ratio (POR) of heavy smoking (≥ 21 cpd) associated with mentholated cigarettes versus non-mentholated cigarettes was 0.7 (95% confidence interval (CI) 0.5 to 0.9) in current smokers and 0.6 (95% CI 0.4 to 0.9) in former smokers. Among whites, the corresponding POR were 0.9 (95% CI 0.8 to 1.0) and 0.9 (95% CI 0.8 to 1.0). Blacks were less likely to have been heavy smokers than whites, but the difference was unrelated to cigarette mentholation. The POR of continued smoking versus quitting, associated with mentholated cigarettes was 1.1 (95% CI 1.0 to 1.2) for both blacks and whites.

Conclusion:Smoking > 20 cpd was independently associated with white race. Among blacks, smoking ≤ 20 cpd was independently associated with mentholated cigarettes. The risk of quitting was not associated with cigarette menthol flavour.
Diverting intracellular trafficking ofSalmonellato the lysosome through activation of the late endocytic Rab7 by intracellular delivery of muramyl dipeptide
Authors: Mukherjee Konark , Parashuraman Seetharaman , Krishnamurthy Ganga , Majumdar Jolly , Yadav Ashok , Kumar Ravi , Basu Sandip K. , Mukhopadhyay Amitabha
Published: November 2002

Previously, we showed that live Salmonella-containing phagosomes(LSP) recruit early acting Rab5 and promote fusion with early endosomes, thus avoiding transport to the lysosomes. Therefore, live Salmonellasurvive in a specialized compartment. Here we show that scavenger-receptor-mediated intracellular delivery of muramyl dipeptide (MDP)to macrophages leads to efficient killing of Salmonella both in vitro and in vivo. To understand the intracellular trafficking modulation of Salmonella by delivery of MDP, we investigated the levels of endocytic Rab proteins, which are the major regulators of vesicular transport. Western blot analysis reveals reduced Rab5 and enhanced Rab7 content in the maleylated bovine serum albumin-MDP (MBSA-MDP)-treated cells. The reduced content of Rab5 in the treated cells and on phagosomes inhibits the fusion of Salmonella-containing phagosomes with early endosomes, and the enhanced Rab7 content in these cells facilitated targeting of LSP to lysosomes, which contain cathepsin D and vacuolar ATPase, for killing. In vitro reconstitution of lysosomal transport demonstrated that a reduced content of Rab5 and an enhanced level of Rab7 in MBSA-MDP-treated cells is primarily responsible for targeting Salmonella to lysosomes. Intracellular delivery of MDP thus offers a general strategy against macrophage-associated infections caused by intracellular pathogens that survive in the host cell by resisting transport to lysosomes.
PKCα-mediated ERK, JNK and p38 activation regulates the myogenic program in human rhabdomyosarcoma cells
Authors: Mauro Annunziata , Ciccarelli Carmela , De Cesaris Paola , Scoglio Arianna , Bouché Marina , Molinaro Mario , Aquino Angelo , Zani Bianca Maria
Published: November 2002

We have previously suggested that PKCα has a role in 12-O-Tetradecanoylphorbol-13-acetate (TPA)-mediated growth arrest and myogenic differentiation in human embryonal rhabdomyosarcoma cells (RD).

Here, by monitoring the signalling pathways triggered by TPA, we demonstrate that PKCα mediates these effects by inducing transient activation of c-Jun N-terminal protein kinases (JNKs) and sustained activation of both p38 kinase and extracellular signal-regulated kinases (ERKs) (all referred to as MAPKs). Activation of MAPKs following ectopic expression of constitutively active PKCα, but not its dominant-negative form, is also demonstrated.

We investigated the selective contribution of MAPKs to growth arrest and myogenic differentiation by monitoring the activation of MAPK pathways, as well as by dissecting MAPK pathways using MEK1/2 inhibitor (UO126), p38 inhibitor (SB203580) and JNK and p38 agonist (anisomycin) treatments. Growth-arresting signals are triggered either by transient and sustained JNK activation (by TPA and anisomycin, respectively) or by preventing both ERK and JNK activation (UO126) and are maintained, rather than induced, by p38. We therefore suggest a key role for JNK in controlling ERK-mediated mitogenic activity. Notably, sarcomeric myosin expression is induced by both TPA and UO126 but is abrogated by the p38 inhibitor. This finding indicates a pivotal role for p38 in controlling the myogenic program. Anisomycin persistently activates p38 and JNKs but prevents myosin expression induced by TPA. In accordance with this negative role, reactivation of JNKs by anisomycin, in UO126-pre-treated cells, also prevents myosin expression. This indicates that,unlike the transient JNK activation that occurs in the TPA-mediated myogenic process, long-lasting JNK activation supports the growth-arrest state but antagonises p38-mediated myosin expression. Lastly, our results with the MEK inhibitor suggest a key role of the ERK pathway in regulating myogenic-related morphology in differentiated RD cells.
Spurious power‐law relations among rainfall and radar parameters
Authors: Jameson A. R. , Kostinski A. B.
Published: November 2002

In previous work, the authors examined statistical physics of rain from the point of view of the modern theory of random processes. In particular, the importance of statistical stationarity (homogeneity) was emphasized in order to attribute a clear physical meaning to the notions of drop size distribution and relations between the radar reflectivity factor, Z, and rainfall rate, R, used in radar meteorology.

In this work we return to the case of the simplest rain model, namely uncorrelated raindrops having a prescribed drop size distribution. As shown in previous work, in such rain linear relations are anticipated among the various rainfall parameters. Taking the direct approach of Monte Carlo simulations and using the techniques typical of rainfall studies over the last several decades, we then sample from a collection of rain events in which the drop occurrences are uncorrelated but each event has the same prescribed drop size distribution. Surprisingly, it is found that apparently realistic but spurious nonlinear power‐law relations still appear among rainfall parameters even though the rain is not only statistically homogeneous but purely random as well.

We show that this occurs largely because of an inadequate number of drops in each sample. The drop samples typically observed, while variable in size, are often too small to sufficiently represent the size distribution or its moments. That is, each sample of rain drops, is one random, partial realization of the probability density function of diameter, that still yields functionally related pairs of variables such as Z and R. We show, however, that because of the inadequate number of drops, n, in each sample the least‐square‐error power‐law fits yield spurious exponents that depend upon n. Thus, even though resulting fits may adequately describe the deficient observations, they are spurious and physically meaningless.

An inspection of the literature reveals that nearly all reported Z–R and other rainfall parameter relations over the last several decades are likely to be spurious because n was too small by factors of hundreds to thousands. It is clear that such fitted relations are unlikely to reflect the actual physical properties of the rain and are simply artefacts of inadequate sampling and, to a lesser extent, fitting procedures. In particular the relations of Marshall and Palmer are probably artefacts. Copyright © 2002 Royal Meteorological Society
Theoretical analysis of resonant tunneling in triple‐barrier structures under electric fields
Authors: Arakawa Masakazu , Yamamoto Hiroaki , Tanaka Satoshi , Yamada Norifumi
Published: November 2002

Assuming a practical device application of resonant tunneling in a triple‐barrier structure, equations for theoretical analysis of the tunneling transmission coefficient and the resonance condition are derived with regard to the tunneling phenomena in asymmetric triple‐barrier structures in the presence of an applied bias. From the numerical analysis results, an interesting phenomenon not observed in structures with two or fewer barriers is found. As the bias voltage is increased, the transmission peak value of the resonant spectrum, which initially decreases, begins to increase again and several peaks with a spectral value of 1 (unity resonance) appear. At that time, the resonance condition is studied. Further, the effect of the tunneling transmission characteristics of triple‐barrier structures on the voltage–current relationship in a triple‐barrier resonant tunneling diode is studied. By means of the equations derived here, the resonant bias voltage in the triple‐barrier structure can be determined. The conclusions derived in this paper are considered useful for the design of resonant tunneling devices using triple‐barrier structures. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 85(12): 10–19, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10075
Analysis of transport properties of five‐terminal beam splitter using anisotropy of the group velocity
Authors: Ueta Tsuyoshi
Published: November 2002

This paper proposes a beam splitter with one emitter and two collectors each on the left and right based on anisotropy of the group velocity. An anisotropic medium is represented by a two‐dimensional square lattice tight‐binding model. The transport property of the beam splitter is analyzed by means of the boundary‐type solution method. At the center of the band where the anisotropy of the group velocity is strong, the incident beam is split into two and propagates along the diagonal directions of the square lattice with almost no diffraction. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 85(12): 67–75, 2002; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/ecjb.1114
Membranes, minerals, and proteins of developing vertebrate enamel
Authors: Diekwisch Thomas G.H. , Berman Brett J. , Anderton Xochitl , Gurinsky Brian , Ortega Adam J. , Satchell Paul G. , Williams Mia , Arumugham Chithra , Luan Xianghong , Mcintosh James E. , Yamane Akira , Carlson David S. , Sire Jean‐Yves , Shuler Charles F.
Published: November 2002

Developing tooth enamel is formed as organized mineral in a specialized protein matrix. In order to analyze patterns of enamel mineralization and enamel protein expression in species representative of the main extant vertebrate lineages, we investigated developing teeth in a chondrichthyan, the horn shark, a teleost, the guppy, a urodele amphibian, the Mexican axolotl, an anuran amphibian, the leopard frog, two lepidosauria, a gecko and an iguana, and two mammals, a marsupial, the South American short‐tailed gray opossum, and the house mouse. Electron microscopic analysis documented the presence of a distinct basal lamina in all species investigated. Subsequent stages of enamel biomineralization featured highly organized long and parallel enamel crystals in mammals, lepidosaurians, the frog, and the shark, while amorphous mineral deposits and/or randomly oriented crystals were observed in the guppy and the axolotl. In situ hybridization using a full‐length mouse probe for amelogenin mRNA resulted in amelogenin specific signals in mouse, opossum, gecko, frog, axolotl, and shark. Using immunohistochemistry, amelogenin and tuftelin enamel proteins were detected in the enamel organ of many species investigated, but tuftelin epitopes were also found in other tissues. The anti‐M179 antibody, however, did not react with the guppy and axolotl enameloid matrix. We conclude that basic features of vertebrate enamel/enameloid formation such as the presence of enamel proteins or the mineral deposition along the dentin‐enamel junction were highly conserved in vertebrates. There were also differences in terms of enamel protein distribution and mineral organization between the vertebrates lineages. Our findings indicated a correlation between the presence of amelogenins and the presence of long and parallel hydroxyapatite crystals in tetrapods and shark. Microsc. Res. Tech. 59:373–395, 2002. © 2002 Wiley‐Liss, Inc.
Unique dentition of lungfish
Authors: Kemp A.
Published: November 2002

Lungfish are a group of ancient fish, represented almost continuously in the fossil record from their first appearance in the Devonian to the present time. They have numerous unique characters in the dentition, found only among lungfish, as well as some that are shared with other groups of fish and with higher vertebrates, such as a thin layer of true enamel, instead of the enameloid found in the dentition of most fish. Unique characters include the diversity of forms of dentine in the tooth plates, as well as the organisation of the dentines and the unusual mode of continuous growth of the dentition. Their enamel is based on amelogenin formed by the ameloblasts of the dental lamina, and is mineralised by long crystals of calcium hydroxyapatite deposited in layers over the developing tooth. The different forms of dentine, which show progressive evolutionary change within the group, are based on an extracellular matrix of collagen, mineralised with calcium hydroxapatite of variable crystalline form. Cells that line the oral cavity produce the ameloblasts that are endodermal in origin, and cells that form the dental papillae are, like the other cells that secrete skeletal tissues, derived from head mesoderm, as in other vertebrates. Unique to all dipnoans is the fusion of the dental tissues to the underlying bone and the way in which bone, included within the tooth plate, remodels to permit growth in the whole dentition. Microsc. Res. Tech. 59:435–448, 2002. © 2002 Wiley‐Liss, Inc.
Bi‐arc graphs and the complexity of list homomorphisms
Authors: Feder Tomas , Hell Pavol , Huang Jing
Published: November 2002

Given graphs G, H, and lists L(v) ⊆ V(H), v ε V(G), a list homomorphism of G to H with respect to the lists L is a mapping f : V(G) → V(H) such that uv ε E(G) implies f(u)f(v) ε E(H), and f(v) ε L(v) for all v ε V(G). The list homomorphism problem for a fixed graph H asks whether or not an input graph G, together with lists L(v) ⊆ V(H), v ε V(G), admits a list homomorphism with respect to L. In two earlier papers, we classified the complexity of the list homomorphism problem in two important special cases: When H is a reflexive graph (every vertex has a loop), the problem is polynomial time solvable if H is an interval graph, and is NP‐complete otherwise. When H is an irreflexive graph (no vertex has a loop), the problem is polynomial time solvable if H is bipartite and H is a circular arc graph, and is NP‐complete otherwise. In this paper, we extend these classifications to arbitrary graphs H (each vertex may or may not have a loop). We introduce a new class of graphs, called bi‐arc graphs, which contains both reflexive interval graphs (and no other reflexive graphs), and bipartite graphs with circular arc complements (and no other irreflexive graphs). We show that the problem is polynomial time solvable when H is a bi‐arc graph, and is NP‐complete otherwise. In the case when H is a tree (with loops allowed), we give a simpler algorithm based on a structural characterization. © 2002 Wiley Periodicals, Inc. J Graph Theory 42: 61–80, 2003
In vivo light dosimetry for motexafin lutetium‐mediated PDT of recurrent breast cancer
Authors: Dimofte Andreea , Zhu Timothy C. , Hahn Stephen M. , Lustig Robert A.
Published: November 2002

Background and Objectives

To measure the fluence at tissue surface for patients in our Phase II clinical trial of motexafin lutetium (MLu)‐mediated chest wall photodynamic therapy for recurrent breast carcinoma and to compare it to the calculated irradiance.

Study Design/Materials and Methods

The spatial and time dependence of light fluence (rate) was monitored in vivo on the chest wall surface using isotropic detectors in five patients. Patients were given MLu either 4 mg/kg with light at 18 hours or 5 mg/kg with light at 24 hours using an irradiance of 150 J/cm2 at 730 nm, with an incident fluence rate of 75 mW/cm2. The ratio of fluence rate to the incident fluence rate was determined at the center of the treatment field. This ratio was used to estimate the effective attenuation coefficient, μeff.

Results

The mean and standard deviation of the ratio for all patients was 1.6 ± 0.2. The corresponding range of μeff was between 0.87 and 2.1 cm−1, assuming reduced scattering coefficient, μ′s = 4 cm−1.

Conclusions

A conversion factor was determined to convert the irradiance to fluence rate on the tissue surface. However, the fluence (or the ratio) on patient surface varied by 70% due to the heterogeneity of optical properties. This supports the use of real‐time in vivo dosimetry during photodynamic therapy. Lasers Surg. Med. 31:305–312, 2002. © 2002 Wiley‐Liss, Inc.
Evaluation of the long pulsed high fluence alexandrite laser therapy of leg telangiectasia
Authors: Brunnberg Stephanie , Lorenz Susanne , Landthaler Michael , Hohenleutner Ulrich
Published: November 2002

Background and Objectives

The treatment of larger leg veins with laser or intense pulsed light often shows varying degrees of success and inconsistent clinical response rates. Aim of this study was to evaluate the effectiveness and safety of the 755 nm long pulsed high fluence alexandrite laser in the treatment of larger leg veins.

Study Design/Materials and Methods

Twenty female volunteers aged 25–51 years (mean 39) with 0.3–1.3 mm leg telangiectasias received laser treatment, 10 of them with an additional pass done right after the first pass. Their skin type ranged from 1 to 3 (five type 1, seven type 2, eight type 3). After test spots with increasing fluences (40–90 J/cm2) to determine the individual safe fluence, the maximum fluence of 90 J/cm2 could be used in all 20 subjects. The spot size was 3 × 10 mm, a spray cooling system was used with 80 milliseconds spray and delay time, respectively. The number of pulses administered ranged from 30 to 467 per subject (mean 139). The treated area was controlled 1 day, 1 month, and 3 months post‐treatment and the side effects were quantified. At each visit, the treatment area was photographed. The percent clearance in the treated areas was scored by two observers. Subject satisfaction was evaluated at the 3 months post‐treatment visit.

Results

After 3 months, in all 20 test subjects some clearance was visible. It ranged from low‐grade to complete clearance. Most subjects (15 of 20) had a clearance between 26 and 75%. Hyperpigmentation was observed in 15 subjects. Hypopigmentation was seen in two subjects. No edema, no purpura, no erythema, no scarring, no blistering, and no crusts were observed. Mean subject satisfaction score was assessed and all volunteers reported to be “satisfied.”

Conclusions

The long pulsed high fluence alexandrite laser is effective and safe in the treatment of leg veins 0.3–1.3 mm in diameter. Lasers Surg. Med. 31:359–362, 2002. © 2002 Wiley‐Liss, Inc.
Standard Language and a Work in Progress
Authors: Bieliauskas Linas A.
Published: November 2002

Compiling a dictionary is a formidable undertaking. Noah
Webster published the first American dictionary in 1806 and
immediately set about revising it to his formidable An American
Dictionary of the English Language published 22 years later
in 1828. The next revision appeared in 1840. These timelines
provide some estimate of the effort involved in such an undertaking.
Current Status of the Neurobiology of Alzheimer's Disease
and the Importance of Early Diagnosis
Authors: Sullivan Edith V.
Published: November 2002

Alzheimer's disease—occurring upward of 15% of
individuals age 65 and older—is the most prevalent
age-related dementia. Since the late 1970s, neuropsychologists
have been instrumental in identifying patterns of sparing and
impairment of cognitive, sensory, and motor functions and rates
of declines in selective functions. Anyone who has engaged in
longitudinal study of AD and anyone of that large segment of
the population with relatives suffering with AD has witnessed
first-hand the relentless, irreversible demise of function and
ultimate loss of dignity characteristic of AD's course.
The approach of Scinto and Daffner's edited book, Early
Diagnosis of Alzheimer's Disease, avoids rehashing
the already established descriptions of AD and provides firm,
scientific rationale for the meaningfulness of early and accurate
diagnosis of AD despite its current dire prognosis and lack
of effective medical treatment.
Clinicians Take Note: Tables for Your
Shelf
Authors: Lezak Muriel D.
Published: November 2002

This heroic undertaking, while it is not an exciting
read, appears to be a necessary addition to the practicing
clinician's reference shelf—the one that's within
arm's reach while preparing a report. It is a dazzlingly
comprehensive review of the literature, reporting on what looks
to be just about every study involving a repeat examination
published between 1970 and 1999.
A meta-analysis of the neuropsychological sequelae of HIV infection
Authors: REGER MARK , WELSH ROBERT , RAZANI JILL , MARTIN DAVID J. , BOONE KYLE B.
Published: November 2002

This meta-analysis summarizes the broad spectrum of
neuropsychological research on HIV disease across a sample of
41 primary studies and an aggregate of 8,616 participants for
10 major neuropsychological ability areas. Analyses of the course
of cognitive decline within and across Centers for Disease Control
classifications reveals statistically significant cognitive
deficits from asymptomatic HIV to AIDS. Effect sizes (Cohen,
1988) were calculated to reflect between-group (asymptomatic,
symptomatic, AIDS) differences in each neuropsychological domain.
Relatively small effect sizes were obtained for the asymptomatic
(0.05–0.21) patients, and generally small to moderate
effect sizes were obtained for symptomatic (0.18–0.65)
HIV+ patients, with motor functioning exhibiting the greatest
effects in this later disease stage. The most notable deficits
in cognitive functioning were found in the AIDS group with moderate
(attention and concentration) to large (motor functioning) effect
sizes with values ranging from 0.42–0.82. Comparison of
cognitive functioning as a function of disease progression revealed
that motor functioning, executive skills, and information
processing speed were among the cognitive domains showing the
greatest decline from early to later stages of HIV. These findings
indicate that cognitive deficits in the early stages of HIV
are small and increase in the later phases of the illness, and
that specific patterns of cognitive deficits can be detected
with disease progression. These results and their clinical utility
are further discussed. (JINS, 2002, 8,
410–424.)
Verbal and spatial working memory performance among HIV-infected
adults
Authors: HINKIN CHARLES H. , HARDY DAVID J. , MASON KAREN I. , CASTELLON STEVEN A. , LAM MONA N. , STEFANIAK MARTA , ZOLNIKOV BRYAN
Published: November 2002

Subtypes of working memory performance were examined in a cohort
of 50 HIV-infected adults and 23 uninfected controls using an
n-back paradigm (2-back) in which alphabetic stimuli
were quasi-randomly presented to a quadrant of a computer monitor.
In the verbal working memory condition, participants determined
whether each successive letter matched the letter that appeared
two previously in the series, regardless of spatial location.
In the spatial working memory condition, participants determined
whether each letter matched the spatial location of the letter
that had appeared two previously, regardless of letter identity.
The dependent variable was percent accuracy in each condition.
Results of mixed model ANOVA revealed that the HIV-infected
participants performed significantly worse than controls on
both the verbal and spatial working memory tasks. A significant
main effect for working memory condition was also present with
both participant groups performing better on the spatial working
memory task. These results, the first study of HIV-infected
adults to directly compare verbal versus spatial working
memory performance using the identical test stimuli across task
conditions, suggests that HIV infection is associated with a
decrement in working memory efficiency that is equally apparent
for both verbal and spatial processing. These findings implicate
central executive dysfunction as a likely substrate and provide
the basis for hypothesizing that decline in working memory may
contribute to other HIV-associated neuropsychological deficits.
(JINS, 2002, 8, 532–538.)
Neural basis of the Stroop interference task: Response
competition or selective attention?
Authors: MEAD LARISSA A. , MAYER ANDREW R. , BOBHOLZ JULIE A. , WOODLEY SCOTT J. , CUNNINGHAM JOSEPH M. , HAMMEKE THOMAS A. , RAO STEPHEN M.
Published: November 2002

Previous neuroimaging studies of the Stroop task have postulated
that the anterior cingulate cortex (ACC) plays a critical role
in resolution of the Stroop interference condition. However,
activation of the ACC is not invariably seen and appears to
depend on a variety of methodological factors, including the
degree of response conflict and response expectancies. The present
functional MRI study was designed to identify those brain areas
critically involved in the interference condition. Healthy subjects
underwent a blocked-trial design fMRI experiment while responding
to 1 of 3 stimulus conditions: (1) incongruent color words,
(2) congruent color words, and (3) color-neutral words. Subjects
responded to the printed color of the word via a manual
response. Compared to the congruent and neutral conditions,
the incongruent condition produced significant activation within
the left inferior precentral sulcus (IpreCS) located on the
border between the inferior frontal gyrus, pars opercularis
(BA 44) and the ventral premotor region (BA 6). Significant
deactivations in the rostral component of the ACC and the posterior
cingulate gyrus were also observed. Selective activation of
the left IpreCS is compatible with findings from previous
neuroimaging, lesion, electrophysiological, and behavioral studies
and is presumably related to the mediation of competing
articulatory demands during the interference condition.
(JINS, 2002, 8, 735–742.)
Substance use and withdrawal: Neuropsychological functioning
over 8 years in youth
Authors: TAPERT SUSAN F. , GRANHOLM ERIC , LEEDY NATHAN G. , BROWN SANDRA A.
Published: November 2002

This study prospectively examined neuropsychological (NP)
functioning associated with adolescent substance use and
withdrawal. Participants were youths with histories of substance
use disorders (n = 47) and demographically comparable
youths with no such lifetime histories (n = 26). They
were followed with NP testing and substance involvement interviews
at 7 time points spanning 8 years, from ages 16 to 24, on average.
After controlling for recent use, age, education, practice effects,
and baseline NP functioning, substance use over the 8-year
follow-up period significantly predicted performances on tests
of memory and attention at Year 8. Additionally, withdrawal
symptoms during the follow-up predicted visuospatial and attention
scores at Year 8. Findings suggest that use and withdrawal may
differentially impact neurocognitive functioning during youth,
with heavy use leading to learning, retention, and attentional
difficulties, and withdrawal leading to problems with visuospatial
functioning. (JINS, 2002, 8, 873–883.)
Neuropsychological manifestations of the genetic mutation
for Huntington's disease in presymptomatic individuals
Authors: BRANDT JASON , SHPRITZ BARNETT , CODORI ANN MARIE , MARGOLIS RUSSELL , ROSENBLATT ADAM
Published: November 2002

A triplet repeat (CAG) expansion mutation in the
huntingtin gene on chromosome 4 is responsible for
Huntington's disease (HD). Presymptomatic genetic testing
for this mutation has identified clinically normal persons who
are virtually certain to develop this dementing illness if they
live a normal lifespan. The present study sought to determine
whether these “mutation-positive” persons have
impairments in cognitive functioning. Seventy-five
mutation-positive persons did not differ from 128 mutation-negative
persons on tests selected for their sensitivity to early-stage
HD. Interestingly, however, those with the mutation viewed
themselves as more likely to develop HD than did those without
the mutation. Among mutation-positive subjects, having a longer
CAG repeat mutation was likewise not associated with
cognitive impairment. However, being closer to estimated disease
onset (a product of repeat length and parent's age at onset)
was associated with selected cognitive impairments. When viewed
in light of previous studies showing atrophy of the caudate
nucleus and putamen in mutation-carriers who are close to onset
but not those far from onset, these results suggest that subtle
changes in brain and behavior may be detected shortly before
subjects with the HD mutation develop sufficient signs and symptoms
for diagnosis. Conceptual and methodological problems associated
with the search for presymptomatic cognitive and behavioral
indicators of dementing illness are discussed. (JINS, 2002, 8, 918–924.)
A Valid Assessment of Contemporary Neuropsychology?
Authors: Milberg William
Published: November 2002

This collection of generally well written reviews
is sure to elicit a variety of reactions from readers interested
in the field of clinical neuropsychology. Many, particularly
those new to neuropsychology will likely appreciate this
well organized and clearly written compilation of chapters
edited by Gerald Goldstein and Theresa M. Incagnoli. The
12 chapters written by some of clinical neuropsychology's
plenipotentiaries cover the main assessment systems currently
employed in the United States. There are also chapters
concerned with the evaluation of such special populations
as severely demented older adults and children. In addition
there are introductory chapters covering longstanding debates
that still occupy some quarters of the neuropsychological
community. To this group of readers Contemporary Approaches
to Neuropsychological Assessment will serve as an
intellectual “county fair” where experts have
proudly displayed the best of their “wares”:
the test systems and ideas with which they have long been
associated. However, there will also be readers who will
find this compilation disconcerting. From the perspective
of many clinicians who are more familiar with the field,
including those who must make a living in the real world
of managed care and the increasing disillusionment of traditional
medical allies of clinical neuropsychology (e.g., behavioral
neurology, the court system, etc.), this volume will appear
overly optimistic and in some cases anachronistic.
Quantitative Modal Determination of Geological Samples Based
on X-ray Multielemental Map Acquisition
Authors: Cossio Roberto , Borghi Alessandro , Ruffini Raffaella
Published: November 2002

Multielemental X-ray maps collected by a remote scanning system
of the electron beam are processed by a dedicated software program
performing accurate modal determination of geological samples.
The classification of different mineral phases is based on
elemental concentrations. The software program Petromod loads
the maps into a database and computes a matrix consisting of
numerical values proportional to the elemental concentrations.
After an initial calibration, the program can perform the chemical
composition calculated on the basis of a fixed number of oxygens
for a selected area. In this way, it is possible to identify
all the mineral phases occurring in the sample. Up to three
elements can be selected to calculate the modal percentage of
the identified mineral. An automated routine scans the whole
set of maps and assigns each pixel that satisfies the imposed
requirements to the selected phase. Repeating this procedure
for every mineral phase occurring in the mapped area, a modal
distribution of the rock-forming minerals can be performed.
The final output consists of a digitized image, which can be
further analyzed by common image analysis software, and a table
containing the calculated modal percentages. The method is here
applied to a volcanic and a metamorphic rock sample.
Microvasculature of the Olfactory Organ in the Japanese Monkey
(Macaca fuscata fuscata)
Authors: Okada Shigenori , Schraufnagel Dean E.
Published: November 2002

Olfaction is an important and primitive sense. As its importance
has changed with evolution, anatomic adjustments have occurred
in its structure and vasculature. Primates are a family of
vertebrates that have had to develop their visual system to
adapt to the arboreal environment and have evolved from a
macrosmatic to a microsmatic species as the optic system has
enlarged. This has resulted in anatomic changes of a small but
critical area at the base of the brain. This paper describes
the three-dimensional vascular anatomy of the olfactory organ
of the Japanese monkey (Macaca fuscata fuscata). This
is best understood by dividing the organ into three parts: the
olfactory tract, olfactory bulb, and olfactory nerves in the
nasal mucosa. The bulb can be partitioned into an outer or cortical
part and inner or medullary part. The vasculature and tissue
were examined grossly and with light microscopy and scanning
electron microscopy of vascular corrosion casts. The olfactory
tract and bulb were supplied by an arteriole from the anterior
cerebral artery on each side. The tract was supplied by capillaries
running spirally with a coarse network. At the olfactory bulb,
the arteriole ramified into the intracortical and medullary
branches that formed capillary networks. The bulbar intracortical
capillaries were divided into two layers with different densities
and vascular patterns. The capillaries of the superficial layer
had a ladder-like pattern. The branches that ran into the medulla
of the olfactory bulb were more widely spaced. Twigs from the
posterior ethmoidal artery ran along the nerve fiber and formed
intra- and extrafascicular networks. Each region of the olfactory
organ had characteristic three-dimensional vascular patterns
that were related to their cellular architecture.
Chemical Microcharacterization of Ultrathin Iodide Conversion
Layers and Adsorbed Thiocyanate Surface Layers on Silver Halide
Microcrystals with Time-of-Flight SIMS
Authors: Verlinden Geert , Gijbels Renaat , Geuens Ingrid
Published: November 2002

The technique of imaging time-of-flight secondary ion mass
spectrometry (TOF-SIMS) and dual beam depth profiling has been
used to study the composition of the surface of tabular silver
halide microcrystals. Analysis of individual microcrystals with
a size well below 1 μm from a given emulsion is possible.
The method is successfully applied for the characterization
of silver halide microcrystals with subpercent global iodide
concentrations confined in surface layers with a thickness below
5 nm. The developed TOF-SIMS analytical procedure is explicitly
demonstrated for the molecular imaging of adsorbed thiocyanate
layers (SCN) at crystal surfaces of individual crystals and
for the differentiation of iodide conversion layers synthesized
with KI and with AgI micrates (nanocrystals with a size between
10 and 50 nm). It can be concluded that TOF-SIMS as a
microanalytical, surface-sensitive technique has some unique
properties over other analytical techniques for the study of
complex structured surface layers of silver halide microcrystals.
This offers valuable information to support the synthesis of
future photographic emulsions.
Functional Genomics on Potato Virus A: Virus Genome-Wide Map of Sites Essential for Virus Propagation
Authors: Kekarainen Tuija , Savilahti Harri , Valkonen Jari P.T.
Published: November 2002

Transposition-based in vitro insertional mutagenesis strategies provide promising new approaches for functional characterization of any cloned gene or genome region. We have extended the methodology and scope of such analysis to a complete viral genome. To map genome regions both essential and nonessential for Potato virus Apropagation, we generated a genomic 15-bp insertion mutant library utilizing the efficient in vitro DNA transposition reaction of phage Mu. We then determined the proficiency of 1125 mutants to propagate in tobacco protoplasts by using a genetic footprinting strategy that simultaneously mapped the genomic insertion sites. Over 300 sites critical for virus propagation were identified, and many of them were located in positions previously not assigned to any viral functions. Many genome regions tolerated insertions indicating less important sites for virus propagation and thus pinpointed potential locations for further genome manipulation. The methodology described is applicable to a detailed functional analysis of any viral nucleic acid cloned as DNA and can be used to address many different processes during viral infection cycles.
The sensitivity of a model's stratospheric tape recorder to the choice of advection scheme
Authors: Gregory A. R. , West V.
Published: November 2002

The sensitivity of a climate model's transport to the choice of numerical advection scheme is investigated using simulations of the stratospheric tape recorder. Significant differences are found between tracers advected with the Heun scheme (with centred spatial differencing) and tracers advected with a flux‐limited total variation diminishing (TVD) scheme. The tape recorder simulated by the TVD scheme propagates upwards unrealistically fast: about three times faster than the tape recorder of the Heun scheme, even though the winds are identical. In contrast, the amplitude of the TVD scheme's tape recorder is more realistic than that of the Heun scheme, which is too strong in the middle stratosphere.

Further off‐line tracer experiments, using a family of conservative, upwind advection schemes, demonstrate how the tape recorder's phase speed decreases as the order of the polynomial representing the tracer's subgrid variation is increased. It is found that schemes with more implicit vertical diffusion than a quasi third‐order scheme produce a tape recorder with unacceptably fast upwards propagation. The sensitivity can only be reproduced in a one‐dimensional model when winds with strong variability are used, highlighting a limitation of the traditional advection tests that use constant winds. The experiments also show that the numerical oscillations produced by non‐monotonic methods, including the Heun scheme, can artificially strengthen the tape‐recorder signal resulting in a unrealistic lack of attenuation with height. Finally, a full climate simulation using a higher‐order, monotonic advection scheme is found to produce a tape recorder that is reasonably realistic, both in speed and amplitude. Copyright © 2002 Royal Meteorological Society
Nonlinear balanced simulation of a baroclinic wave
Authors: Ziemia'NSKI Micha Z. , Thorpe Alan J.
Published: November 2002

The nonlinear balanced time integration of a baroclinic wave with a model applicable for synoptic and meso‐scale weather systems and based on the conservation of the Ertel–Rossby potential vorticity (PV) is presented. The simulation is performed for a realistic, but idealized, atmospheric configuration involving troposphere, stratosphere and flexible tropopause. The balanced model, compared with the primitive equation (PE) one, proves to be highly accurate. The balanced integration allowed strict implementation of the conservation of PV for the simulation of frontal processes, without generation of spurious low‐level PV anomalies, which emerge in PE simulations of baroclinic waves in the region of frontal collapse. Also, a hypothesis is formulated on the substantial role of these PV anomalies in the baroclinic amplification of the modelled PE baroclinic wave at advanced stages of its evolution. Copyright © 2002 Royal Meteorological Society
Simulations of regional climatic effects of vegetation change in China
Authors: Zheng Yiqun , Yu Ge , Qian Yongfu , Miao Manqian , Zeng Xinmin , Liu Huaqiang
Published: November 2002

In the context of a regional climate model (RegCM2), simulation is undertaken of climatic effects of changed vegetation over China with their possible mechanisms studied, reaching results which show that the increase in flood events over the Yangtze–Huai River valleys and the aggravation of north‐China droughts are likely to be under the joint action of desertification of the northern grassland, and southern degradation of evergreen broadleaf trees, the latter seeming to be the primary factor. Severe vegetation degeneration leads to a positive feedback between rainfall reduction and degradation with the consequence that the disaster expands steadily outward and the area affected is difficult to turn back into farmland. In contrast, less heavy degeneration causes a negative feedback between deterioration and rainfall reduction, and the stricken sector is likely to be reclaimed when human damages are decreased or removed. However, degeneration strengthens surface runoff, allowing flood occurrence. Vegetation deterioration makes the climate even more inhospitable. On the other hand, experiments show that the vegetation enlargement of northern grassland will lead to a mild climate, responsible for precipitation reduction in the outer belts of afforestation, possibly causing newly‐planted trees to die stepwise inwardly, a result that means the current climate in the grassy land does not seem to support a plan of large‐scale afforestation there. Study of climatic response to changed surface roughness and albedo shows that the former more strongly affects rainfall, atmospheric circulation patterns and humidity field, and the latter strongly affects temperature. Moreover, surface‐released effective thermal fluxes (sensible and latent heat) follow the change in vegetation, and so does their Bowen ratio, thereby resulting in a change in moist static energy distribution in the atmosphere, followed by a corresponding alteration of atmospheric stratification and vertical motion, which, in turn, affects vapour transportation that, in connection with changed vertical motion, leads to rainfall variation. Copyright © 2002 Royal Meteorological Society
On the thermodynamics of the oceanic general circulation: Irreversible transition to a state with higher rate of entropy production
Authors: Shimokawa Shinya , Ozawa Hisashi
Published: November 2002

The mechanism of transitions among multiple steady states of thermohaline circulation is investigated from a thermodynamic viewpoint. An oceanic general‐circulation model is used to obtain the multiple steady states under the same set of wind forcing and mixed boundary conditions, and the rate of entropy production is calculated during time integration. Three states with northern sinking and four states with southern sinking are shown to exist in the model by perturbing the high‐latitude salinity. It is found that for transitions among southern sinkings the transition tends to occur from a state with a lower rate of entropy production to a state with a higher rate of entropy production, but the transition in the inverse direction does not occur. These transitions can thus be said to be irreversible or directional, in the direction of the increase of the rate of entropy production. For transitions between northern sinking and southern sinking, the rate of entropy production can either increase or decrease depending on the direction of the perturbation. The decrease is found to be associated with a collapse of the northern sinking circulation by a certain amount of negative salt (positive fresh water) perturbation to the northern hemisphere. After this collapse, a new southern sinking circulation develops, and the corresponding rate of entropy production increases. All these results tend to support the hypothesis that a nonlinear system is likely to move to a state with maximum entropy production by perturbation. Copyright © 2002 Royal Meteorological Society
Momentum flux due to trapped lee waves forced by mountains
Authors: Broad A. S.
Published: November 2002

A simple, but general, horizontal momentum budget for inviscid flow is developed to understand how the vertical flux of horizontal momentum varies with height in a mountain‐forced trapped lee‐wave train. Taking a sinusoidal form for the wave field, from the analytical solution for a two‐layer Scorer‐parameter atmosphere, the constant Bernoulli functional on a streamline is used to diagnose the momentum flux. It is shown that in an inviscid, steady wave train the magnitude of the momentum flux decreases with height as a sinusoidal function. The present theory clearly shows how this profile of momentum flux with height is a direct consequence of the exact balance between the vertical derivative of momentum flux and the dynamic pressure difference across the mountain in steady state. The simple analytic profile of flux with height shows a remarkable qualitative similarity with numerical‐model results from idealized case‐studies of flow over an isolated mountain ridge. © Crown copyright, 2002.