bluuebunny/crossref_metadata_2025 huggingface dataset:
Evolutionary computation to control unnatural water level fluctuations in multi‐reservoir river systems
Authors: Dessalegne Tibebe , Nicklow John , Minder Eric
Published: August 2004

A methodology and computational model for evaluation and optimization of dam operations in multi‐reservoir river systems is presented. The optimal dam operation scheme was defined as that which minimizes unnatural water level fluctuations during low flow periods, subject to the maintenance of desired stages within the river network, desired storage levels in the reservoirs, and bounds on releases from dams. The dam operation problem was solved using a discrete‐time optimal control methodology in which a genetic algorithm was interfaced with an existing, unsteady, one‐dimensional hydraulic simulation model known as FLDWAV. The hydraulic simulation model was used to solve governing hydraulic constraints, while the genetic algorithm was employed to solve the overall control problem. Constraints on water surface and storage levels were handled using an Additive Penalty Method. Two types of objective functions, absolute water surface deviation and rate of water surface fluctuation, were considered and their results were compared. Capabilities of the overall model were demonstrated through applications to a hypothetical three‐reservoir river system and a portion of the Illinois River Waterway, for which the hydraulic simulation model was calibrated and verified. Copyright © 2004 John Wiley & Sons, Ltd.
Interactive effects of basin features and land‐use change on macroinvertebrate communities of headwater streams in the Patagonian Andes
Authors: Miserendino M. Laura , Pizzolon Lino A.
Published: August 2004

Composition and structure of macroinvertebrate communities were documented in relation to hydrochemical variables over a 10‐month period in four headwater tributaries of the Futaleufú River, northwestern Chubut, Argentina. The streams are located along the strong rainfall gradient that decreases from west to east and they have different basin features. At Blanco and Baggilt streams, riparian vegetation consisted primarily of native Nothofagus forest, while in the Nant y Fall and Rifleros, basins with a long legacy of domestic grazing, the introduced Salix fragilis was the dominant riparian species. Macroinvertebrate species richness, density, and biomass were similar among rivers; however, biomass of shredders was highest in the Nothofagus forested streams and collector‐filterers were significantly higher in Salix fragilis‐bordered rivers. Water temperatures were higher in non‐native Salix sites than in the native or mixed forested sites. Canonical community analysis indicated community composition was related to geomorphic attributes of the rivers, especially slope, basin height (elevation change), distance to the source, substratum size, and Salix coverage. Moreover, seasonally dynamic variables, rainfall and water temperature were good community predictors. Land‐use change (conversion from Nothofagus to pastures and the Salix fragilis invasion in the riverbanks of pasture‐dominated catchments) was interactive with natural stream attributes as determinants of macroinvertebrate distribution and abundance. Copyright © 2004 John Wiley & Sons, Ltd.
TOPS (Task Optimization in the Presence of Signal‐Dependent Noise) model
Authors: Miyamoto Hiroyuki , Nakano Eri , Wolpert Daniel M. , Kawato Mitsuo
Published: August 2004

This paper proposes a movement trajectory planning model, which is a maximum task achievement model in which signal‐dependent noise is added to the movement command. In the proposed model, two optimization criteria are combined, maximum task achievement and minimum energy consumption. The proposed model has the feature that the end‐point boundary conditions for position, velocity, and acceleration need not be prespecified. Consequently, the method can be applied not only to the simple point‐to‐point movement, but to any task. In the method in this paper, the hand trajectory is derived by a psychophysical experiment and a numerical experiment for the case in which the target is not stationary, but is a moving region. It is shown that the trajectory predicted from the minimum jerk model or the minimum torque change model differs considerably from the results of the psychophysical experiment. But the trajectory predicted from the maximum task achievement model shows good qualitative agreement with the hand trajectory obtained from the psychophysical experiment. © 2004 Wiley Periodicals, Inc. Syst Comp Jpn, 35(11): 48–58, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10377
Latent variable modelling of recovery trajectories: sexual function following radical prostatectomy
Authors: Legler Julie M. , Davis William W. , Potosky Arnold L. , Hoffman Richard M.
Published: August 2004

As treatments improve and survival time lengthens, the course of recovery and long‐term quality of life (QoL) is of greater interest. The application of latent class growth models to longitudinal QoL data provides unique insights into recovery that are not evident with marginal analyses. We examine this approach in the context of a large population‐based observational study. This is the first attempt to characterize individuals' recovery over time following prostate cancer surgery, and to determine factors associated with varying recovery experiences of prostate cancer patients. Four major patterns emerged that illustrate typical patterns of recovery following radical prostatectomy. Given a man's baseline data, this method produces estimates of the probability of belonging to each recovery class. The method is presented as a useful tool for identifying hypotheses associated with recovery and potential antecedents of importance. Published in 2004 by John Wiley & Sons, Ltd.
Stratification and weighting via the propensity score in estimation of causal treatment effects: a comparative study
Authors: Lunceford Jared K. , Davidian Marie
Published: August 2004

Estimation of treatment effects with causal interpretation from observational data is complicated because exposure to treatment may be confounded with subject characteristics. The propensity score, the probability of treatment exposure conditional on covariates, is the basis for two approaches to adjusting for confounding: methods based on stratification of observations by quantiles of estimated propensity scores and methods based on weighting observations by the inverse of estimated propensity scores. We review popular versions of these approaches and related methods offering improved precision, describe theoretical properties and highlight their implications for practice, and present extensive comparisons of performance that provide guidance for practical use. Copyright © 2004 John Wiley & Sons, Ltd.
Experience with the architectural design of a modest product family
Authors: Schwanke Robert W. , Lutz Robyn R.
Published: August 2004

Many product families are modest in the sense that they consist of a sequence of incremental products with, at any point in time, only a few distinct products available and minimal variations among the products. Such product families, nevertheless, are often large, complex systems, widely deployed, and possessing stringent safety and performance requirements. This paper describes a case study that tends to confirm the value of using a product‐line approach for the architectural design of a modest product family. The paper describes the process, design alternatives, and lessons learned, both positive and negative, from the architectural design of one such family of medical image analysis products. Realized benefits included identifying previously unrecognized common behavior and sets of features that were likely to change together, aligning the architecture with specific market needs and with the organization, and reducing unplanned dependencies. Most interesting were the unanticipated benefits, including decoupling the product‐family architecture from the order of implementation of features, and using the product‐family architecture as a ‘guiding star’ with subsequent releases moving toward, rather than away from, the planned architecture. Copyright © 2004 John Wiley & Sons, Ltd.
Source model analysis using the JJTraveler visitor combinator framework
Authors: van Deursen Arie , Visser Joost
Published: August 2004

Program understanding tools manipulate program representations, such as abstract syntax trees, control‐flow graphs, or data‐flow graphs. This paper deals with the use of visitor combinators to conduct such manipulations. Visitor combinators are an extension of the well‐known visitor design pattern. They are small, reusable classes that carry out specific visiting steps. They can be composed in different constellations to build more complex visitors. We evaluate the expressiveness, reusability, ease of development, and applicability of visitor combinators to the construction of program understanding tools. To that end, we conduct a case study in the use of visitor combinators for control‐flow analysis and visualization as used in a commercial Cobol program understanding tool. Copyright © 2004 John Wiley & Sons, Ltd.
Enforcing direct communications between clients and Web servers to improve proxy performance and security
Authors: Chen Songqing , Zhang Xiaodong
Published: August 2004

The amount of dynamic Web contents and secured e‐commerce transactions has been dramatically increasing on the Internet, where proxy servers between clients and Web servers are commonly used for the purpose of sharing commonly accessed data and reducing Internet traffic. A significant and unnecessary Web access delay is caused by the overhead in proxy servers to process two types of accesses, namely dynamic Web contents and secured transactions, not only increasing response time, but also raising some security concerns. Conducting experiments on Squid proxy 2.3STABLE4, we have quantified the unnecessary processing overhead to show its significant impact on increased client access response times. We have also analyzed the technical difficulties in eliminating or reducing the processing overhead and the security loopholes based on the existing proxy structure. In order to address these performance and security concerns, we propose a simple but effective technique from the client side that adds a detector interfacing with a browser. With this detector, a standard browser, such as the Netscape/Mozilla, will have simple detective and scheduling functions, called a detective browser. Upon an Internet request from a user, the detective browser can immediately determine whether the requested content is dynamic or secured. If so, the browser will bypass the proxy and forward the request directly to the Web server; otherwise, the request will be processed through the proxy. We implemented a detective browser prototype in Mozilla version 0.9.7, and tested its functionality and effectiveness. Since we have simply moved the necessary detective functions from a proxy server to a browser, the detective browser introduces little overhead to Internet accessing, and our software can be patched to existing browsers easily. Copyright © 2004 John Wiley & Sons, Ltd.
Congenital curly toe of the fetus
Authors: Cho J. Y. , Park J. H. , Kim J. H. , Lee Y. H.
Published: August 2004

Objectives

To assess the prevalence, prenatal detection rate, and associated anomalies of congenital curly toe in an unselected obstetric population.

Methods

Between September 2001 and July 2002, 1167 singleton fetuses in the second and third trimesters underwent routine prenatal ultrasound at our hospital. Congenital curly toe was diagnosed when the fourth or fifth toe was not fully delineated on the axial image with medial and plantar flexion on the coronal image. All neonates underwent a physical examination within 3 days after delivery. Radiography was performed on those infants with curly toe. We assessed the prevalence, prenatal detection rate, and associated anomalies of the condition.

Results

There were 38 congenital curly toes among the 1167 neonates, yielding a total prevalence of 32.6 per 1000. In 26 of the 38 the fourth toe was curly and in 12 the fifth toe was curly. Of those in which the fourth toe was curly, 26.9% involved the right toe, 65.4% the left, and 7.7% involved both toes. For a curly fifth toe, these values were 25.0%, 16.7% and 58.3%, respectively. There was no associated structural anomaly, chromosomal abnormality, or syndrome in any case. Sixteen of the 38 curly toes were detected on prenatal ultrasound, including 13 of 26 with the fourth toe being curly and three of 12 with the fifth being curly.

Conclusions

Congenital curly toe is not an uncommon condition, and can be detected on the prenatal ultrasound. Although it usually appears as an isolated finding without clinical significance, thorough ultrasound examination of the fetus should be recommended. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Adaptive control of heterogeneous ad hoc networks
Authors: Kulkarni S. S. , Dattatreya G. R. , Martinez H. , Soto R.
Published: August 2004

Heterogeneous ad hoc networks are proposed as a solution to the scalability problem in pure ad hoc networks. Some of the links in heterogeneous networks have a much longer wireless transmission range (in one or more of their channels) than the other links. We study simple approaches for adaptive operation and performance optimization of such networks. Our study includes the following: (a) Use of very simple functions of observed performance for adaptive control; (b) Accommodation of an operational constraint imposed by a higher layer in the network. In this case, traffic from a forwarding node to a neighboring node, meant for an eventual destination, can be multiplexed over either long range links or over short range links but not both; (c) Route selection using extremely simple, predetermined criteria; (d) Performance comparison of the above three simplified approaches to the original algorithm of Reference [4]. The original algorithm is computationally more accurate, but handicapped by the absence of long range links.

Our approaches are illustrated with simulation experiments on heterogeneous ad hoc networks fielding synthetic self‐similar (bursty) traffic. The performance comparisons of the approaches are presented for both fixed as well as dynamic network topologies. They emphasize the advantage of heterogeneous network operation over a pure ad hoc network, all nodes in the latter being functionally identical. Copyright © 2004 John Wiley & Sons, Ltd.
Synthesis of Pure Cementitious Phases by Sol‐Gel Process as Precursor
Authors: Stephan Dietmar , Wilhelm Patrick
Published: August 2004

Calcium silicates and aluminates are the main constituents of ordinary Portland cement (OPC) and calcium aluminate cements (CAC) and therefore the pure phases are of great importance for the investigation of interactions between binder and additives or admixtures. Additionally, investigations on clinker phases doped with foreign ions enable the improvement of the performance of cements. For this purpose great amounts of pure phases are needed. These phases are hard to synthesize via a solid state reaction of solid educts. Thus there is a need for a new, more efficient route to synthesize these phases. The sol‐gel process as precursor provides an alternative to the conventional method. In this paper experimental evidence is presented for an improved synthesis of calcium silicates and aluminates via sol‐gel processes, the characterisation of these clinker phases and their hydration behaviour.
Synthesis and Structure of the new Fluoride Bromide Ba6.668(2)Ca0.332(2)F12Br2 and Solid Solutions with Composition Ba7−xCaxF12(ClyBr1−y)2 with x = ∼0.5, 0 < y < 1
Authors: Frühmann B. , Kubel F. , Hagemann H. , Bill H.
Published: August 2004

Crystals of the chemical composition Ba7F12Cl2 were modified by adding a small amount of Ca2+ to allow the synthesis of the corresponding bromine compound Ba[Ca]7F12Br2. These samples were prepared in a NaBr flux and characterized by single crystal x‐ray diffraction. The new structure crystallizes in a disordered arrangement in the hexagonal space group P63/m (176). The calcium ion has a coordination number of 6.

Solid solutions on the heavy halide position can be synthesised in a NaCl/NaBr flux to obtain the compounds Ba7−xCaxF12(ClyBr1−y)2 with x = ∼0.5 and 0 < y < 1.

Regardless the amount of calcium used in the preparation process, the Ca stoichiometry in the compound is always between 0.3 and 0.5. The lattice parameters differ depending on the Ca‐ and Br‐content between 1053.81(5) ⩽ a = b ⩽ 1058.93(3) pm and 421.21 ⩽ c ⩽ 426.78(3) pm.
Investigation of Structural Relationships between Racemic Alkali and Ammonium Hydrogen Tartrates and their Chiral Counterparts
Authors: Gelbrich Thomas , Threlfall Terence L. , Huth Susanne , Seeger Eva , Hursthouse Michael B.
Published: August 2004

Single crystals of racemic anhydrous alkali and ammonium hydrogen tartrates of the composition M(C4H5O6) with M = K, Rb, Cs, NH4 as well as MxM′1−x(C4H5O6) with {M = K, M′ = Rb, x = 0.5}, {M = K, M′ = NH4, x = 0.56} and {M = Rb, M′ = NH4, x = 0.61} were obtained from the reaction of D,L‐tartaric acid with the corresponding hydroxides MOH and / or M′OH. These compounds form an isostructural series (monoclinic, P21/c, Z = 4). The structures consist of alternating tartrate anion layers and cation layers. Each tartrate layer is held together by a number of hydrogen bonds and contains exclusively either the D or the L‐form of the tartrate. Structural analogies between these crystals and their chiral counterparts are investigated. The smilarity of cell parameters between racemic and chiral structures is shown to be a consequence of certain packing features that occur in both groups.
1,2‐Dithioquadratato‐ und 1,2‐Dithiooxalatoindate(III)
Authors: Wenzel Barbara , Wehse Burkhard , Schilde Uwe , Strauch Peter
Published: August 2004

Indium(III)‐chlorid bildet in wäßriger Lösung mit Kalium‐1,2‐Dithiooxalat (dto) und Kalium‐1,2‐Dithioquadratat (dtsq) stabile Koordinationsverbindungen. Während aufgrund der ausgeprägteren Brückenbildungstendenz mit 1,2‐Dithiooxalat in allen untersuchten Fällen thiooxalatverbrückte Zweikernkomplexe gebildet werden, können mit 1,2‐Dithioquadratat bei identischem Donoratomsatz einkernige Trischelatkomplexe isoliert werden. Mit (BzlMe3N)4[(dto)2In(dto)In(dto)2] (1), (BzlPh3P)4[(dto)2In(dto)In(dto)2] (2), (BzlMe3N)3[In(dtsq)3] (3), (Bu4N)3[In(dtsq)3] (4) und (Ph4P)[In(dtsq)2(DMF)2] (5) konnten fünf Komplexe kristallin isoliert und mittels Röntgenkristallstrukturanalyse charakterisiert werden. In Abhängigkeit vom Typ der Komplexe und dem jeweiligen Kation kristallisieren die Verbindungen in unterschiedlichen Raumgruppen. Strukturparameter s. Abstract.
Neutrale Bis‐Aziridin‐Komplexe des Typs [M(CO)3XAz2] (M = Mn, Re; X = Cl, Br; Az = N(H)C2H2Me2)
Authors: Wilberger Roland , Krinninger Christoph , Piotrowski Holger , Mayer Peter , Ossberger Manfred , Lorenz Ingo‐Peter
Published: August 2004

In einer thermisch induzierten Substitutionsreaktion mit 2,2‐Dimethylaziridin lassen sich die Pentacarbonyl‐Halogeno‐Komplexe [XM(CO)5] (M = Mn, Re; X = Cl, Br) (1a – 2b) zu den neutralen Bis‐Aziridin‐Komplexen [M(X)(CO)3Az2] (Az = N(H)C2H2Me2) (3a – 4b) umsetzen. Den Röntgenstrukturanalysen zufolge sind die Metallatome oktaedrisch in facialer Anordnung konfiguriert; die intakten Dreiringe sind über die verzerrt tetraedrisch konfigurierten N‐Atome gebunden. Verbindungen 3a – 4b sind hinsichtlich einer gezielten Alken‐Abspaltung unter Bildung von Nitren‐Komplexen stabil; ihre IR‐, 1H‐ und 13C{1H}‐NMR‐ und MS‐Spektren werden vorgestellt und diskutiert.
Über Kaliumtetracyanoplatinat(II), Kaliumtetracyanopalladat(II) und deren Monohydrate
Authors: Mühle Claus , Nuss Jürgen , Dinnebier Robert E. , Jansen Martin
Published: August 2004

Wir haben die Kristallstrukturen der Kaliumtetracyanoplatinate und ‐palladate sowie deren Monohydrate mittels Röntgen‐Pulverdiffraktometrie und Einkristallstrukturanalyse bestimmt. K2[Pt(CN)4]: orthorhombisch, Pccn, a = 1370.11(2), b = 907.09(1), c = 703.91(2) pm, Z = 4, RF2 = 0.0903 (N(hkl) = 415). K2[Pt(CN)4] · H2O: orthorhombisch, Pnna, a = 715.79(4), b = 977.91(6), c = 1322.46(8) pm, Z = 4, R(F)N′ = 0.027 (N′(hkl) = 1066). K2[Pd(CN)4]: monoklin, P21/c, a = 433.03(2), b = 782.90(3), c = 1328.17(6) pm, ß = 93.069(3)°, Z = 2, Rp = 0.0583 (N(hkl) = 352). K2[Pd(CN)4] · H2O: orthorhombisch, Pnna, a = 721.48(6), b = 976.77(8), c = 1326.4(1) pm, Z = 4, R(F)N′ = 0.048 (N′(hkl) = 1137). In allen untersuchten Vertretern liegen die Anionen übereinander gestapelt, wenn auch teilweise gekippt, vor. Die Ergebnisse werden durch spektroskopische und thermoanalytische Untersuchungen ergänzt.
Mechanisms of Calcium and Phosphate Ion Association in Aqueous Solution
Authors: Zahn Dirk
Published: August 2004

The initial steps of nucleation of calciumphosphates in aqueous solution are elucidated by means of quantum / classical molecular mechanics simulations. A special focus is dedicated to the role of the protonation state of the phosphate ion. The crystallization of calciumphosphates including entirely deprotonated phosphate ions is found at much lower pH values than required for finding the (PO4)3− species in water. In such cases the depronation of the hydrogenphosphate ion has to occur during crystal growth. According to our findings, the [Ca2+··(PO4)3−··Ca2+] ion triple is the smallest stable aggregate, which may be expected to contain an entirely deprotonated phosphate ion.
Synthesis, IR Spectra, Thermal Analysis and Crystal Structures of Bis(saccharinato)mercury(II) Complexes with 2–Aminomethylpyridine and 2–Aminoethylpyridine
Authors: Yilmaz Veysel T. , Caglar Sema , Harrison William T. A.
Published: August 2004

Two bis(saccharinato) (sac) complexes of mercury(II) with 2–aminomethylpyridine (ampy) and 2–aminoethylpyridine (aepy) were synthesized and characterized by means of elemental analysis, FT–IR spectroscopy and thermal analysis and single crystal X–ray diffraction. trans–[Hg(sac)2(ampy)2] (1) crystallizes in the monoclinic space group P21/c [a = 10.8274(4), b = 16.4903(6), c = 7.7889(3) Å; β = 99.500(1)°] and [Hg(sac)2(aepy)] (2) also crystallizes monoclinic in space group P21/n [a = 9.0423(4), b = 14.0594(6), c = 18.0146(8) Å; ß = 98.806(1)°]. Both 1 and 2 consist of neutral monomeric units. The mercury(II) ion in 1 lies on an inversion centre and exhibit distorted octahedral coordination by two sac anions and two ampy ligands, whereas the mercury(II) ion in 2 is tetrahedrally coordinated by an aepy and two sac ligands. The sac ligands in both complexes are N–coordinated, while the ampy and aepy ligands act as a bidentate ligand forming two symmetrically chelate rings around the mercury(II) ion.
Doppelkettenstruktur von (pipzH2)[MnF2(HPO4)(H2O)](H2PO4)
Authors: Stief Ronald , Massa Werner
Published: August 2004

Aus einer fluß‐ und phosphorsauren Lösung von Mangan(III)fluorid läßt sich durch Zugabe von Piperazin das Fluoridphosphat (pipzH2)[MnF2(HPO4)(H2O)](H2PO4) kristallisieren, das neben Piperazinium(2+)‐Kationen und freien (H2PO4)−‐Anionen eine abwechselnd aus [HPO4]‐Tetraedern und [MnO3F2(H2O)]‐Oktaedern aufgebaute anionische Doppelkette aufweist. Die Struktur ist triklin, Raumgruppe P$\bar 1$, Z = 2, a = 622.97(4), b = 923.46(6), c = 1183.62(7) pm, α = 98.343(6)°, β = 100.747(7)°, γ = 107.642(5)°, R = 0.0289, Bemerkenswerterweise findet man ferrodistortive Jahn‐Teller‐Ordnung stark gestreckter [MnO3F2(H2O)]‐Oktaeder mit Elongation der senkrecht zur Kettenebene stehenden F–Mn–OH2‐Achsen. Die Struktur wird durch sehr starke H‐Brücken stabilisiert.
Erythropoietin improves left ventricular function and coronary flow in an experimental model of ischemia‐reperfusion injury
Authors: van der Meer Peter , Lipsic Erik , Henning Robert H. , de Boer Rudolf A. , Suurmeijer Albert J.H. , van Veldhuisen Dirk J. , van Gilst Wiek H.
Published: August 2004

Background:

Recent studies show that erythropoietin (EPO) plays a protective role in brain ischemia. In this condition, administration of EPO protects neurons from ischemic damage. Recently, it has been shown that in patients with chronic heart failure (CHF), EPO treatment improved cardiac function. In the present study we assessed the role of EPO and EPO‐receptor (EPO‐R) in the heart.

Methods and results:

We studied the presence and functionality of the EPO‐R in isolated rat hearts in the Langendorff set‐up. Hearts were perfused for 20 min with 10 U/ml EPO or vehicle. Immunohistochemistry revealed the presence of the EPO‐R on endothelial cells, fibroblasts and to a lesser extent cardiomyocytes. Furthermore, perfusion with EPO resulted in a 50% increase in the phosphorylated MAP kinases p42/p44. To evaluate the protective role of EPO in cardiac ischemia, we performed low‐flow (0.6 ml/min) ischemia/reperfusion experiments in isolated rat hearts. Administration of EPO (10 U/ml) reduced the cellular damage by 56% (P<0.05) during reperfusion, diminished apoptosis by 15% (P<0.05) and resulted in a significantly improved recovery of left ventricular pressure (P=0.02) and coronary flow (P=0.01).

Conclusion:

The present data suggest that a functional EPO‐R is present in rat adult cardiac tissue and that exogenous EPO administration improves cardiac function after ischemia/reperfusion injury.
Factor structure of the CERAD neuropsychological battery
Authors: STRAUSS MILTON E. , FRITSCH THOMAS
Published: August 2004

The Consortium to Establish a Registry for Alzheimer's Disease
(CERAD) neuropsychological battery was developed to evaluate cognitive
impairments associated with Alzheimer's disease (AD). Previous
studies have suggested that the battery is multi-dimensional,
represented by either 3 or 5 dimensions. In this study a principal
factor analysis was conducted using contemporary quantitative methods
for determining the number of factors. Exploratory factor analysis of
the CERAD battery and MMSE was conducted using one-half of the CERAD
database (total N = 969). Glorfeld's modification of
Horn's parallel analysis method suggested that there was 1 common
factor in the variable matrix. Characterization of patterns of deficits
in AD requires supplementation of measures derived from the CERAD and
MMSE with other tests. (JINS, 2004, 10,
559–565.)
Emotional and nonemotional facial expressions in people with
Parkinson's disease
Authors: SIMONS GWENDA , PASQUALINI MARCIA C. SMITH , REDDY VASUDEVI , WOOD JULIA
Published: August 2004

We investigated facial expressivity in 19 people with
Parkinson's disease (PD; 14 men and 5 women) and 26 healthy
controls (13 men and 13 women). Participants engaged in experimental
situations that were designed to evoke emotional facial expressions,
including watching video clips and holding conversations, and were
asked to pose emotions and imitate nonemotional facial movements.
Expressivity was measured with subjective rating scales, objective
facial measurements (Facial Action Coding System), and self-report
questionnaires. As expected, PD participants showed reduced spontaneous
facial expressivity across experimental situations. PD participants
also had more difficulty than controls posing emotional expressions and
imitating nonemotional facial movements. Despite these difficulties,
however, PD participants' overall level of expressivity was still
tied to emotional experience and social context. (JINS, 2004,
10, 521–535.)
Global–local visual processing in posttraumatic stress disorder
Authors: VASTERLING JENNIFER J. , DUKE LISA M. , TOMLIN HOLLY , LOWERY NATASHA , KAPLAN EDITH
Published: August 2004

The purpose of this study was to examine a behavioral index of hemispheric asymmetry (i.e., visual hierarchical attention) in posttraumatic stress disorder (PTSD), a disorder characterized by anxiety and other emotional symptoms. A reaction time based, computerized, global–local visual paradigm was administered to 26 PTSD-diagnosed and 22 psychopathology-free right-handed, male Vietnam War zone veterans. Results indicated that PTSD-diagnosed veterans displayed slower reaction times to all targets than the no-mental disorders comparison sample. However, findings also revealed a Group × Target location interaction in which the PTSD group was slower than the no-disorders comparison sample to respond to local, but not global, targets. Moreover, relative global bias was greater among PTSD-diagnosed veterans than their no-diagnosis counterparts. Findings provide partial support for the hypothesis that PTSD may be associated with a functional cerebral asymmetry favoring the right hemisphere. (JINS, 2004,10, 709–718.)
Neurocognitive profiles in elderly patients with frontotemporal degeneration or major depressive disorder
Authors: ELDERKIN-THOMPSON VIRGINIA , BOONE KYLE B. , HWANG SUN , KUMAR ANAND
Published: August 2004

Major depressive disorder (MDD) and frontotemporal dementia (FTD) are both disorders in elderly populations that involve the prefrontal cortex and appear to have similar neurocognitive deficits. This review examined whether there are testable deficits in cognition that are consistent across individuals within the same neuropathological condition that could be used to facilitate early diagnoses. Medline and PsychInfo databases were searched for cognitive studies of depressed and FTD patients that used a matched control group and reported findings with means and standard deviations (N= 312). Effect sizes for FTD patients with mild and moderately advanced disease were compared to effect sizes within subgroups of depressed patients, such as inpatients, outpatients and community volunteers. Moderately advanced FTD patients were more impaired than depressed patients over all domains, particularly in language ability, although depressed inpatients appeared similar to FTD patients in some domains. Effect sizes for FTD patients who were in the mild, or early, stage of the disease (MMSE= 28) were similar to those of depressed outpatients but slightly worse than those of community volunteers in all domains except semantic memory and executive ability. In the latter two domains, even mild FTD patients had notably large deficits. All FTD patients showed more severe deficits in some domains relative to other domains. In contrast, depressed patients tended to vary by clinical presentation or disease severity, but the magnitude of impairment for each subgroup remained relatively consistent across domains and they did not have the severe focal deficits in one or two domains demonstrated by FTD patients. (JINS, 2004,10, 753–771.)
Stability of vocational outcome in adulthood after moderate to severe preschool brain injury
Authors: NYBO TAINA , SAINIO MARKKU , MÜLLER KITI
Published: August 2004

We studied how moderate to severe childhood traumatic brain injury (TBI) affects vocational outcome with time. This is the second follow-up of patients who were injured as preschoolers in traffic accidents. In the first follow-up the mean age was 23 years and in the present study the average age of the 27-patient cohort was 40 years. Twenty-two patients were assessed clinically by a neuropsychologist, neurologist and a social worker. Five patients, although not able or willing to participate in the clinical study, were contacted by telephone and interviewed on their vocational outcome. Compared to the first follow-up, 20/27 patients in total had no change in their vocational status. Nine out of the 27 patients were working full-time, two had subsidized jobs and 16 were not working. Twenty-four of 27 patients were independent in daily living. In the neuropsychological tests of executive functions, preserved flexibility associated with full-time work status. In conclusion, 1/3 of the patients were still employed full-time over 30 years after the TBI. This suggests that favorable vocational outcome, reached by young adulthood, is maintained at least until middle age. (JINS, 2004,10, 719–723.)
Selbsterhaltungstherapie: Konzept, klinische Praxis und bisherige Ergebnisse
Authors: Romero Barbara
Published: August 2004

Zusammenfassung: Mit der Selbsterhaltungstherapie (SET) wurde ein (neuro)psychologisch fundiertes Rehabilitationsprogramm für Demenzkranke, insbesondere für Personen mit einer Alzheimer Demenz, konzipiert und in dieser Zeitschrift zum ersten Mal veröffentlicht ( Romero & Eder, 1992 ). Als übergeordnetes Rehabilitationsziel wurde die Erhaltung des Selbst in seiner Kohärenz und Funktionsfähigkeit eingeführt. Die SET fand Anwendung in der klinischen Praxis, sowohl im ambulanten und stationären Bereich wie in Heimen. Die meisten Erfahrungen liegen aus dem Alzheimer Therapiezentrum (ATZ) Bad Aibling vor. Das ATZ bietet stationär medikamentöse Behandlung in Verbindung mit einem Rehabilitationsprogramm für Demenzkranke und einem psychoedukativen Programm für betreuende Angehörige an. Die Ergebnisse der bisherigen begleitenden empirischen Studien zeigen eine Verbesserung des Wohlbefindens (z. B. der Depressivität) nach der Behandlung, sowohl bei Kranken als auch bei Angehörigen. Mögliche Wirkmechanismen des therapeutischen Erfolges werden diskutiert.
A multiple time window rupture model for the 1999 Chi‐Chi earthquake from a combined inversion of teleseismic, surface wave, strong motion, and GPS data
Authors: Thio H. K. , Graves R. W. , Somerville P. G. , Sato T. , Ishii T.
Published: August 2004

We present the results of a comprehensive analysis of the rupture process of the 1999 Chi‐Chi, Taiwan, earthquake using a broad array of seismic as well as geodetic data, spanning a very wide frequency band. Our results indicate that the rupture was quite smooth, with the slip concentrated in a wide arcuate region north of the epicenter with very little slip to the east or south. We found a moment of 3.3 × 1027 dyn cm, which is consistent with the long‐period determinations for this earthquake. The rupture velocity is approximately 2.25 km/s and is quite uniform across the fault. We have tested both a single fault plane model as well as a composite fault model with a second E‐W striking plane to the north of the rupture to improve the fit of the geodetic data. Overall, the differences in slip distribution between the two models are negligible, but the fit to the GPS data is significantly better for the composite model, which is thus our preferred solution. This model is similar to other rupture models as far as the large‐scale features are concerned but differs for the smaller asperities that are present in other models but not as much in ours. These are usually poorly constrained, and with the use of the geodetic data we believe that there is little evidence for a significant amount of slip away from our main slip concentration.
Crystallinity of foraminifera shells: A proxy to reconstruct past bottom water CO3= changes?
Authors: Bassinot Franck C. , Mélières Frédéric , Gehlen Marion , Levi Camille , Labeyrie Laurent
Published: August 2004

The reconstruction of past changes in bottom water CO3= is central to evaluating competing oceanic scenarios that deal with long‐term variations in atmospheric pCO2. In search of a quantitative bottom water CO3= proxy, we analyzed the variations of calcite crystallinity of planktonic foraminifera Globigerinoides ruber shells picked from core top samples along three depth transects: Ontong Java Plateau and the northeast margin of Irian Jaya, in the western equatorial Pacific, and the Sierra Leone Rise, in the eastern tropical Atlantic. The strong empirical relationship between calcite crystallinity (inferred from the full width at half maximum (FWHM) of calcite (104) X‐ray diffraction peak) and bottom water saturation relative to calcite (ΔCO3) shows that foraminifera calcite crystallinity could be a promising proxy for the reconstruction of upper Pleistocene bottom water carbonate ion concentration.
Experimental and analytical modeling of basaltic ash explosions at Mount Etna, Italy, 2001
Authors: Taddeucci J. , Spieler O. , Kennedy B. , Pompilio M. , Dingwell D. B. , Scarlato P.
Published: August 2004

The summer 2001 flank eruption of Mount Etna ended with repeated basaltic ash explosions. The explosions were similar to small‐scale Vulcanian blasts and probably originated when a plug of magma at the top of the conduit became overpressurized. We use three independent methods to estimate the overpressure in the plug: (1) To determine the pressure differential required to fragment the plug, we use a shock tube apparatus to heat and pressurize ballistic blocks at temperature T up to 900°C and pressure P up to 25 MPa and rapidly decompress them to ambient conditions; (2) we apply a model to determine the overpressure generated by microlite growth at depth because pyroclasts from the explosions have 35 vol % more microlites than preceding Strombolian product; and (3) we relate the range of ballistic blocks to their exit velocity and, with models for Vulcanian eruptions, the exit velocity to pressure in the conduit. Experiments and ejecta range bracket the overpressure driving the explosions between ∼3 and ∼5 MPa: below 2.5 MPa the blocks would not reach the observed range, but above 5 MPa the existing blocks with 20% porosity would not survive the explosions. Crystallization of 35 vol % microlites at a depth of ∼100 m increases the pressure in the plug to ∼6 MPa above atmospheric, enough to drive the explosions, with a possible contribution from deeper volatiles. Combining the different methods, we also constrain the exsolved water at fragmentation at ∼0.05 wt % and provide inferences on how the explosions came to an end.
Study of the mixed layer depth variations within the north Indian Ocean using a 1‐D model
Authors: Babu K. N. , Sharma Rashmi , Agarwal Neeraj , Agarwal Vijay K. , Weller R. A.
Published: August 2004

Mixed layer depth (MLD) over the north Indian Ocean (30°S to 30°N and 40°E to 110°E) is computed using the simple one‐dimensional model of Price et al. [1986] forced by satellite‐derived parameters (winds and chlorophyll). Seasonal chlorophyll observations obtained from the Coastal Zone Color Scanner allow us to examine how biology interacts with physics in the upper ocean by changing the absorption of light and thus the heating by penetrative solar radiation, an effect we refer to as biological heating. Our analysis focus mainly on two aspects: the importance of varying biology in the model simulations relative to runs with constant biology and secondly, the contribution of biology to the seasonal variability of the MLD. The model results are compared with observations from a surface mooring deployed for 1 year (October 1994 to October 1995) in the central Arabian Sea and also with available conductivity‐temperature‐depth (CTD) observations from the Arabian Sea during the period 1994–1995. The effect of biological heating on the upper ocean thermal structure in central Arabian Sea is found to be greatest in August. In other months it is either the wind, which is the controlling factor in mixed layer variations, or the density variations due to winter cooling and internal dynamics. A large number of CTD observations collected under the Joint Global Ocean Flux study and World Ocean Circulation Experiment have been used to validate model results. We find an overall improvement by approximately 2–3 m in root‐mean‐square error in MLD estimates when seasonally varying chlorophyll observations are used in the model.
Ablation and associated energy balance of a horizontal glacier surface on Kilimanjaro
Authors: Mölg Thomas , Hardy Douglas R.
Published: August 2004

The surface energy balance of a glacier describes the physical connection between ice/snow ablation and climatic forcing. To expand knowledge on the response of Kilimanjaro's glaciers to climate variations, this study estimates the energy balance on a horizontal glacier surface at the summit for the periods March to September 2000 and March 2001 to February 2002. An automatic weather station (AWS) operating at 5794 m above sea level provides the data input, and ablation at the AWS site differed considerably between the two periods. The energy balance model employed incorporates radiative fluxes, turbulent heat fluxes, and the energy flux in the subsurface. On a monthly basis, results show that radiative energy dominates energy exchanges at the glacier‐atmosphere interface, governed by the variation in net shortwave radiation. The turbulent latent heat flux, which is always negative (i.e., continuous mass loss due to sublimation), is the second important energy flux. In contrast, turbulent exchange of sensible heat remains of minor importance. The marked difference in ablation between the two periods can largely be explained by a difference in surface albedo. Albedo depends on precipitation amount and frequency and directly controls net shortwave radiation receipt. In the context of modern glacier retreat on Kilimanjaro the results support other evidence that Kilimanjaro's glaciers are extremely sensitive to precipitation variability.
Geometry of Martian impact craters: First results from an interactive software package
Authors: Mouginis‐Mark Peter J. , Garbeil Harold , Boyce Joseph M. , Ui Celine S. E. , Baloga Stephen M.
Published: August 2004

We have developed a new interactive computer program that facilitates the easy collection of geomorphic data for Martian impact craters, using the MOLA 128th degree digital elevation model of Mars. We describe the method for ensuring that accurate measurements of crater diameter, depth, rim height, rim volume, cavity volume, ejecta thickness, and ejecta volume are obtained. We compare our measurements of crater diameters and rim heights to results obtained by Garvin et al. [2000], who employed centerline MOLA profiles. Statistical regressions between the two methods give R2 values of 0.930 for crater depths and 0.984 for crater diameters. The new interactive program facilitates the rapid compilation of large data sets to allow a comparison of crater populations in different settings. Preliminary results are presented for 354 craters on ridged plains materials in Hesperia and Sinai Plana to demonstrate the value of the program for regional comparisons and the analysis of degradational processes on Mars.
Lithium abundance and isotope systematics of forearc serpentinites, Conical Seamount, Mariana forearc: Insights into the mechanics of slab‐mantle exchange during subduction
Authors: Benton Laurie D. , Ryan Jeffrey G. , Savov Ivan P.
Published: August 2004

Variable lithium contents and contrasting Li isotopic signatures are evident in the serpentininite muds and clasts extruded at Conical Seamount in the Mariana forearc. The muds have high Li contents compared to mantle values (3–7 ppm) and a mean δ7Li value of ∼+6‰. The clasts are generally lower in Li, and δ7Li varies from −6‰ to +10‰, with higher δ7Li correlating broadly to higher lithium contents. The diverse δ7Li in the serpentinite clasts suggests Li exchanges between mantle rocks and evolving slab‐derived fluids from different depths, producing a subarc mantle that is zoned in terms of Li abundances and δ7Li. Mariana forearc Li isotopic signatures reach values as high as those reported in Mariana arc lavas, but neither Mariana lavas nor lavas from other “mature” arcs show the variability observed in the serpentinites. Although elevated serpentinite Li contents indicate forearc releases of Li, large differences in δ7Li are not evident in the slab outputs at forearc versus arc depths in the Marianas, despite evidence for changes in other alkaline species (e.g., Ba, Sr, K). It is thus possible that the Li sampled by Mariana arc volcanoes is in large part Li which was released in the forearc and transported in the mantle via convection to arc depths, as has been proposed to explain B isotopic variations [Straub and Layne, 2002]. The uniform δ7Li signatures observed in “mature” volcanic arcs [Tomascak et al., 2002] are consistent with higher overall fluxes of slab fluids, which generate larger melting anomalies, including both modified and nonmodified mantle wedge domains. High or low δ7Li in lavas from anomalous arcs (e.g., Panama [Tomascak et al., 2000]) may indicate that the volumes of mantle sampled in these magmatic events are smaller and thus more likely to reflect the signatures of hydrated “plums” [e.g., Allègre and Turcotte, 1986; Phipps Morgan and Morgan, 1999] with extremely high or low δ7Li.
Venting formation fluids from deep‐sea boreholes in a ridge flank setting: ODP Sites 1025 and 1026
Authors: Wheat C. Geoffrey , Jannasch Hans W. , Kastner Miriam , Plant Josh N. , DeCarlo Eric H. , Lebon Geoff
Published: August 2004

During ODP Leg 168, two of ten boreholes, ODP Holes 1025C and 1026B, were cased through the sediment section, penetrated basaltic crust that is overpressured, and sealed. In 1999 and 2000 the seals were removed, allowing crustal formation fluids to vent and be sampled. The composition of these fluids is compared to those of basal deep‐sea pore waters, which have been the basis for estimating geochemical fluxes from low‐temperature ridge flank hydrothermal systems. Estimates for the composition of the major ions in formation fluids based on basal pore waters are within 5% of the values measured in borehole fluids. Similar comparisons for minor and trace elements are not as good; some are reactive in the sediment section, resulting in large uncertainties in the pore water extrapolation, while others are influenced by a variety of contaminants, including steel, grease, drilling muds, and basal sediment. Evidence for contamination includes high dissolved and particulate concentrations of several metals (e.g., Fe, Cu, Co, Zn, and Pb) and measurable changes in concentration during the past four years in response to reaction with basal sediment. This new confidence in estimating the primary composition of formation fluids, coupled with advances in thermodynamic and kinetic models, reveals the possibility of anhydrite precipitation in ridge flank hydrothermal systems at temperatures of ∼70°C. Such new insights allow us to address the timing and conditions under which seawater‐crustal reactions occur, leading to more accurate models of crustal evolution.
Low‐frequency of southern Asian monsoon variability using a 295‐year record from the Dasuopu ice core in the central Himalayas
Authors: Duan Keqin , Yao Tandong , Thompson L. G.
Published: August 2004

A better understanding of the spatial and temporal variability of rainfall in the Himalayas should be extremely important to improve our understanding of Asian monsoon dynamics. There is little that is understood about rainfall variability at the high Himalayas with elevation over 7000 m a.s.l. Here a high‐resolution snow accumulation record from a well dated Dasuopu ice core from central Himalayas reflects low‐frequency variability of monsoon precipitation over the last 295‐year. MultiDecadal to centennial variations in the Dasuopu snow accumulation (DSA) are in‐phase (out‐of‐phase) with that in monsoon rainfall of northeast Indian, Nepal and Bangladesh (southern India) over the period 1901–1995. The record shows the monsoon in central Himalayas had weakened in 18th century and strengthened throughout much of 19th and early 20th century, and then weakening again from early 1920s to the present.
Interdecadal change in potential predictability of the Indian summer monsoon
Authors: Goswami B. N.
Published: August 2004

A quantitative estimate using daily circulation data for 55 years reveals that the potential predictability of monthly mean summer monsoon climate (a ratio between ‘external’ and ‘internal’ interannual variances) has decreased by almost a factor of two during the decades of 1980's and 1990's as compared to that during 1950's and 1960's associated with the major interdecadal transition of climate in mid‐1970's. During the same period, however, the potential predictability of the summer climate over the central and eastern tropical Pacific has increased by a factor of two. The decrease in potential predictability of monsoon is partly due to a large decrease in ‘external’ variability during the recent decades as a result of interdecadal modulation of the mean monsoon circulation and partly due to ‘internal’ variability remaining relatively high. It is shown that the decrease in ‘internal’ variability due to decrease in intraseasonal activity during this period is rather small and can not compensate the decrease is ‘external’ variability resulting in significant decrease in monsoon predictability.