bluuebunny/crossref_metadata_2025 huggingface dataset:
Model Studies Towards Stephaoxocanes: Construction of the 2‐Oxa‐4‐aza‐ phenalene Core of Stephaoxocanidine and Eletefine
Authors: Bianchi Darío A. , Cipulli Marcos A. , Kaufman Teodoro S.
Published: December 2003

The construction of the polysubstituted 1H,3H‐2‐oxa‐4‐azaphenalene 4 by means of consecutive oxa‐Pictet−Spengler and Jackson cyclizations is reported. This compound contains the ABC ring system of the novel isoquinoline alkaloids stephaoxocanidine and eletefine, found in Stephania cepharantha and Cissampelos glaberrima. Both these species are Menispermaceæ used in folk medicine in the Far East and Brazil. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003
Simultaneous Generation of Anionic and Neutral Palladium(II) Complexes from η3‐Allylpalladium Chloride Dimer and Fluorinated β‐enaminones
Authors: Bouquillon Sandrine , Bouillon Jean‐Philippe , Thomas Louis , Plantier‐Royon Richard , Chanteau Frédéric , Tinant Bernard , Hénin Françoise , Portella Charles , Muzart Jacques
Published: December 2003

Reactions between η3‐allylpalladium chloride dimer, 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) and 1‐amino‐2‐fluoro‐1‐perfluoroethyl‐3‐phenylprop‐1‐en‐3‐one or 1,12‐diamino2,11‐difluoro‐1,12‐bis(perfluorobutyl)dodeca‐1,11‐diene3,10‐dione simultaneously provided two types of PdII complexes. One is an anionic η3‐allylpalladium complex with protonated DBU as counterion while the other is a neutral η3‐allyl(β‐ketoiminato)palladium complex. A mechanism involving the amidine function of DBU in the formation of the two complexes is proposed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Transition‐Metal‐Free Sonogashira‐Type Coupling Reactions in Water
Authors: Appukkuttan Prasad , Dehaen Wim , Van der Eycken Erik
Published: December 2003

Microwave‐assisted transition‐metal‐free Sonogashira‐type coupling reactions are described. The reactions are run in water as the sole solvent, without the need for copper(I) or any transition‐metal−phosphane complex. The scope of the methodology was tested by reaction of a wide variety of aryl halides and heteroaryl halides. The reaction was also investigated under conventional heating conditions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Mechanism of the Kulinkovich Cyclopropanol Synthesis: Transfer‐Epititanation of the Alkene in Generating the Key Titanacyclopropane Intermediate
Authors: Eisch John J. , Adeosun Adetenu A. , Gitua John N.
Published: December 2003

An investigation of the Kulinkovich cyclopropanol synthesis, the interaction of esters with 2:1 or 3:1 mixtures of alkyl Grignard reagents and Ti(OiPr)4 at low temperatures, has been conducted, in order to ascertain which reactive intermediates are involved and how they are interconverted. Because of the nature of the ultimate product, one of the most obvious intermediates is the 1,1‐diisopropoxy‐1‐titanacyclopropane stemming from the epititanation of the alkene set free from the alkyl Grignard reagent employed. A search for the formation of such a titanocycle by warming an ethereal solution of either Et2Ti(OiPr)2 or iPr2Ti(OiPr)2 between −78 °C and +25 °C was attempted by chemical trapping with either an ester or nitrile. In this manner it was shown that such a titanocycle was formed in the case of Et2Ti(OiPr)2 but not with iPr2Ti(OiPr)2. As to the role of two other potential intermediates, Ti(OiPr)2 and R2Ti(OiPr)2, it was demonstrated that preformed Ti(OiPr)2 in the presence of ethylene and an ester does not form the corresponding cyclopropanol. Thus, under the reaction conditions Ti(OiPr)2 cannot perform the direct epimetallation necessary to produce the requisite titanacyclopropane. On the other hand, either iPr2Ti(OiPr)2 or Et2Ti(OiPr)2 can achieve the transfer‐epititanation of ethylene at low temperatures and hence with methyl benzoate yield 1‐phenyl‐1‐cyclopropanol. In contrast, neither iPr2Ti(OiPr)2 nor Et2Ti(OiPr)2 can at low temperatures transfer‐epititanate propylene. This difference in alkene reactivity can be ascribed to steric factors operating in the proposed octahedral transition state for transfer‐epimetallation. Finally, by introducing free ethylene into such Kulinkovich reaction mixtures, either by ethylene gas itself or a third equivalent of EtMgX, the isolated yields of cyclopropanols were more than doubled over those obtained with a 1:2 ratio of Ti(OiPr)4/EtMgX. From this observation one can conclude that free ethylene catalytically initiates the Kulinkovich reaction by coordinating with Et2Ti(OiPr)2 and undergoes transfer‐epititanation to produce the requisite titanacyclopropane and thereby liberates ethylene, which perpetuates the reaction. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
DNA end sequestration by DNA‐dependent protein kinase and end joining of sterically constrained substrates in whole‐cell extracts
Authors: Lee Jae Wan , Inamdar Kedar V. , Hannah Michele F. , Lees‐Miller Susan P. , Povirk Lawrence F.
Published: December 2003

Extracts of Xenopus eggs and of cultured human and hamster cells have the capacity to join nonhomologous DNA ends, and all do so with similar specificity. To examine the formation of repair complexes on DNA under conditions of end joining, end‐labeled fragments were incubated with the various extracts and then subjected to DNase‐I footprinting. Human and Xenopus extracts produced footprints virtually identical to that of purified DNA‐dependent protein kinase holoenzyme (Ku plus DNA‐PKcs), with protection of the terminal 28 bp. Extracts of hamster cells were more variable, but usually produced a 16‐bp footprint, similar to that of Ku alone. In all cases a 28‐bp holoenzyme‐like footprint was associated with wortmannin‐sensitive end joining, minimal 3′‐5′ exonucleolytic resection, and a predominance of accurate end‐joining products. To determine whether the short segments of DNA occupied by Ku and DNA‐PK were sufficient to support end joining, Y‐shaped substrates were constructed in which only one arm was available for end joining. A Y substrate with a 31‐bp arm bearing a partially cohesive 3′ overhang was accurately joined by a Xenopus egg extract, whereas a substrate with a 21‐bp arm was not. Surprisingly, a human cell extract did not join the Y substrates at all. The results suggest that differences in wortmannin sensitivity and in the distribution of in vitro end‐joining products may be attributable to the variations in the levels of DNA‐PKcs in the extracts. In addition, end joining in human extracts appears to involve interactions with significantly longer segments of DNA than the ∼28 bp occupied by DNA‐PK. Environ. Mol. Mutagen. 42:279–287, 2003. © 2003 Wiley‐Liss, Inc.
Genetic toxicity of methamphetamine in vitro and in human abusers
Authors: Li Jih‐Heng , Hu Heng‐Cheng , Chen Wei‐Bang , Lin Shih‐Ku
Published: December 2003

Methamphetamine (METH) is a widely abused psychomotor stimulant. Although numerous studies have examined METH‐induced neurotoxicity, its ability to produce genotoxic effects has not been evaluated. In this article, we report on the genotoxicity of METH in vitro and in human METH abusers. METH induced his+ revertants in Salmonella typhimurium strains TA98 and TA100, and increased the frequency of hprt mutants, micronuclei, and sister chromatid exchange (SCE) in cultured Chinese hamster ovary K1 (CHO‐K1) cells. These METH‐induced genotoxic effects were eliminated if METH exposure was conducted in the presence of rat liver S9, indicating that the genotoxicity was caused by METH, and not by metabolites of METH. In addition, reactive oxygen species (ROS) scavengers inhibited the METH‐induced micronuclei in CHO‐K1 cells. Further investigation with 76 human long‐term METH abusers and 98 unexposed controls demonstrated that total METH exposure correlated with micronucleus and SCE frequencies in cultured lymphocytes. The results of this study indicate that METH is a genotoxic agent and that ROS may play a role in METH‐induced genotoxicity. Environ. Mol. Mutagen. 42:233–242, 2003. © 2003 Wiley‐Liss, Inc.
Increased transcriptional activity of the CYP3A4*1B promoter variant
Authors: Amirimani B. , Ning B. , Deitz A.C. , Weber B.L. , Kadlubar F.F. , Rebbeck T.R.
Published: December 2003

Numerous single nucleotide polymorphisms (SNPs) have been identified in the human genome, yet the functional significance of most is unknown. CYP3A4 is a key enzyme in the metabolism of numerous compounds. An A→G substitution 290 bp upstream of the CYP3A4 transcription start site (CYP3A4*1B) has been associated with cancer phenotypes, but its phenotypic effects are unclear. To investigate the functional significance of CYP3A4*1B, we generated two luciferase reporter constructs: 1‐kb (denoted L, long) and 0.5‐kb (denoted S, short) promoter fragments containing either the variant (VL,VS) or the wild‐type (WL, WS) sequences. We evaluated the effect of the variant sequence in the HepG2 and MCF‐7 cell lines, and in primary human hepatocytes from three donors. Reporter constructs with the variant sequence had 1.2‐ to 1.9‐fold higher luciferase activity than constructs with wild‐type sequence in the cell lines (P < 0.0001) and hepatocytes (P = 0.021, P = 0.027, P = 0.061). The ratio of transcriptional activity for VS:WS was similar to the VL:WL ratio in HepG2 cells, but the VS:WS ratio was consistently less than the VL:WL ratio in MCF‐7 cells. This suggests that CYP3A4 expression is higher from the variant promoter and that a repressor sequence may exist in the longer constructs. Electrophoretic mobility shift assays demonstrated specific binding of a component of HepG2 nuclear extract to both wild‐type and variant promoters with consistently higher binding affinities to the wild‐type sequence. This suggests the existence of a transcriptional repressor responsible for the lower CYP3A4*1A activity. Therefore, the phenotypic effects of the variant CYP3A4*1B may be associated with enhanced CYP3A4 expression due to reduced binding of a transcriptional repressor. Environ. Mol. Mutagen. 42:299–305, 2003. © 2003 Wiley‐Liss, Inc.
The Unemployed and the Question of Solidarity
Authors: Hamann Silke , Karl Astrid
Published: December 2003

Rampant mass unemployment and the discussion about the future of social security raises many questions. A study examines to what extent social welfare benefits are accepted amongst the population
The Fire Salamander: Source for New Species
Authors: Steinfartz Sebastian , Tautz Diethard
Published: December 2003

What you should know about the colourful fire salamanders: how a new species arises through adaptation to its environment is of general interest
Studying the Curved Flight Pattern of Locusts
Authors: Kutsch Wolfram , Berger Sebastian , Fischer Hanno
Published: December 2003

Using miniaturised remote data transmission, biologists examine the flight motions of free flying desert locusts and other insects. Computer‐based video technology reconstructs behavioural sequences
Commentary: Prospects for a Living Community
Authors: Peters Ursula
Published: December 2003

The humanities demand flexible funding instruments — special requirements must be accommodated
A Gossamer Veil — News from the Nanoworld
Authors: Greiner Andreas , Steinhart Martin , Wendorff Joachim H. , Wehrspohn Ralf
Published: December 2003

Tube‐like objects play a special role in the nanoworld. New preparation methods have been developed for making nanotubes. Such innovative procedures provide the basis for a multitude of technical applications
Neural correlates of segmental and tonal information in speech perception
Authors: Gandour Jack , Xu Yisheng , Wong Donald , Dzemidzic Mario , Lowe Mark , Li Xiaojian , Tong Yunxia
Published: December 2003

The Chinese language provides an optimal window for investigating both segmental and suprasegmental units. The aim of this cross‐linguistic fMRI study is to elucidate neural mechanisms involved in extraction of Chinese consonants, rhymes, and tones from syllable pairs that are distinguished by only one phonetic feature (minimal) vs. those that are distinguished by two or more phonetic features (non‐minimal). Triplets of Chinese monosyllables were constructed for three tasks comparing consonants, rhymes, and tones. Each triplet consisted of two target syllables with an intervening distracter. Ten Chinese and English subjects were asked to selectively attend to targeted sub‐syllabic components and make same‐different judgments. Direct between‐group comparisons in both minimal and non‐minimal pairs reveal increased activation for the Chinese group in predominantly left‐sided frontal, parietal, and temporal regions. Within‐group comparisons of non‐minimal and minimal pairs show that frontal and parietal activity varies for each sub‐syllabic component. In the frontal lobe, the Chinese group shows bilateral activation of the anterior middle frontal gyrus (MFG) for rhymes and tones only. Within‐group comparisons of consonants, rhymes, and tones show that rhymes induce greater activation in the left posterior MFG for the Chinese group when compared to consonants and tones in non‐minimal pairs. These findings collectively support the notion of a widely distributed cortical network underlying different aspects of phonological processing. This neural network is sensitive to the phonological structure of a listener's native language. Hum. Brain Mapping 20:185–200, 2003. © 2003 Wiley‐Liss, Inc.
Fetal brain activity in response to a visual stimulus
Authors: Fulford Jonathan , Vadeyar Shantala H. , Dodampahala Senani H. , Moore Rachel J. , Young Paul , Baker Philip N. , James David K. , Gowland Penny A.
Published: December 2003

Previous studies have demonstrated the use of functional magnetic resonance imaging (fMRI) to assess fetal brain activity. To extend these studies, a fetal fMRI experiment using a visual stimulus has been performed at 0.5 T. This used a block fMRI paradigm with a bright, constant‐intensity light source being shone at the maternal abdomen for 8 sec followed by 16 sec of darkness. This was repeated typically 40 times on nine subjects all of whom were greater than 36 weeks gestational age. Of these, one could not be analysed due to motion, three did not show significant activation, and five showed significant activation (P < 0.0085). In all cases, activation was localised within the frontal cortex. Exact localisation was difficult but this may correspond to the frontal eye fields and dorsolateral prefontal cortex. In no cases was significant activation present within the occipital region as would have been expected and was observed in 2/8 adult subjects. Hum. Brain Mapping 20:239–245, 2003. © 2003 Wiley‐Liss, Inc.
Detecting low‐frequency functional connectivity in fMRI using a self‐organizing map (SOM) algorithm
Authors: Peltier Scott J. , Polk Thad A. , Noll Douglas C.
Published: December 2003

Low‐frequency oscillations (<0.08 Hz) have been detected in functional MRI studies, and appear to be synchronized between functionally related areas. A current challenge is to detect these patterns without using an external reference. Self‐organizing maps (SOMs) offer a way to automatically group data without requiring a user‐biased reference function or region of interest. Resting state functional MRI data was classified using a self‐organizing map (SOM). Functional connectivity between the left and right motor cortices was detected in five subjects, and was comparable to results from a reference‐based approach. SOMs are shown to be an attractive option in detecting functional connectivity using a model‐free approach. Hum. Brain Mapping 20:220–226, 2003. © 2003 Wiley‐Liss, Inc.
Willingness to pay for a QALY
Authors: Gyrd‐Hansen Dorte
Published: December 2003

A willingness to pay (WTP) per quality‐adjusted‐life year (QALY) of DKK 88 was estimated on the basis of elicited preferences for health states. The WTP per QALY estimate presented here differs considerably from that implied in contingent valuation studies, suggesting that WTP for reducing risk of death is based on other preference structures than is ex post WTP for improvements in quality of life. Results further suggest that different preference structures may exist when respondents are faced with WTP questions in which case elimination of minor health problems are associated with negligible utility. Copyright © 2003 John Wiley & Sons, Ltd.
Stack unit mapping of coastal aquifer to predict and control sea water intrusion using remote sensing and a geographical information system
Authors: Moses Edwin J. , Thirumalaivasan D.
Published: December 2003

Aquifers are inherently susceptible to contamination and coastal aquifers in specific are highly vulnerable to sea water intrusion. For efficient planning and management of coastal aquifers in Kayalpattu and Tiruchopuram villages, which extend over 4·05 km2, it is essential to delineate and predict the extent of intrusion into the shallow aquifer. Management of ground water in coastal aquifers is composed of major elements that should be properly evaluated, and special attention is given to the sea water intrusion problem. Different data, like hydro‐geomorphological and depth‐wise iso‐apparent resistivity, are integrated spatially using a geographical information system. The stack‐unit mapping approach is used to delineate the zones with iso‐apparent resistivity of less than 10 Ω m have been found to be increasing in areal extent with reference to depth. Copyright © 2003 John Wiley & Sons, Ltd.
The influence of diurnal temperatures on the hydrochemistry of a tufa‐depositing stream
Authors: Drysdale R. , Lucas S. , Carthew K.
Published: December 2003

At‐a‐station diurnal variations in carbonate hydrochemistry were measured during four observation periods at Davys Creek, a tufa‐depositing stream in central NSW, Australia. Major ion concentrations and continuously logged measurements of specific conductivity, pH and temperature showed that changes in the amount of CaCO3 deposited upstream of the study reach were directly related to changes in diurnal water temperatures, which control the rate of CO2 efflux to the atmosphere. The greatest upstream losses occurred during the mid‐afternoon water temperature peak, whereas the lowest upstream losses occurred at sunrise, when water temperatures were at their lowest. Cloudy days at all times of the year produced small diurnal water temperatures ranges (c. 2–5°C) and, consequently, relatively small changes in upstream CaCO3 loss (23–50 mg L−1) through the day. Clear sunny days, especially during summer months, produced large diurnal water temperature changes (up to c. 11°C), which in turn triggered diurnal changes in upstream CaCO3 loss of up to 100 mg L−1. By implication, the active reach of tufa deposition must advance downstream and increase in length during the evening and vice versa during the day. Given that the temperature of Davys Creek waters are a function of insolation, changes in the reach of tufa deposition under baseflow conditions are a direct function of the prevailing weather. This has implications for the palaeoclimatic interpretation of fossil tufa deposits. Copyright © 2003 John Wiley & Sons, Ltd.
Hydromorphological and biological factors influencing sediment and phosphorus loss via bank erosion in small lowland rural streams in Denmark
Authors: Laubel A. , Kronvang B. , Hald A. B. , Jensen C.
Published: December 2003

Bank erosion was measured at 91 stream banks located in 15 Danish rural 1st and 2nd order streams over a 2‐year period. Our aims were firstly to examine factors controlling spatial variation in bank erosion, secondly to estimate sediment and phosphorus (P) loss via bank erosion. The overall mean bank erosion rate was 11 mm year−1. Bank erosion rate over the 2‐year period was significantly related to a number of site‐specific characteristics, including bank angle, bank vegetation cover, overhanging bank and estimated stream power. An empirical model for bank erosion based on these descriptive variables yielded a 55% explanation of the observed spatial variation in bank erosion rate. Bank erosion was higher at the lower 50‐cm bank section (20 mm year−1) than at the upper bank (6 mm year−1). Cattle fencing in grazed areas and buffer zones with riparian woodland lowered bank erosion rates. We found that total P content of bank material was high (0·64 g P kg−1) and at the same level as found in agricultural topsoil along the streams. The overall annual catchment loss of bank‐derived clay–silt sediment and total P to streams amounted to 58–72 kg sediment ha−1 and 0·23–0·28 kg P ha−1, respectively. In comparison, the mean annual suspended sediment (SS) and total P losses from 14 similar sized Danish agricultural catchments were 122 kg SS ha−1 and 0·58 kg P ha−1 over the 2‐year study period. Thus, bank erosion seems to be a major contributor of suspended sediment and P in this type of small channelized lowland stream. Copyright © 2003 John Wiley & Sons, Ltd.
Communication strategies for leading teams
Authors: Adizes Ichak
Published: December 2003

To capture the best thinking of your team, understand the differences among your people.
The journey to authenticity
Authors: George Bill
Published: December 2003

Authentic leaders demonstrate five key characteristics.
Rhythmic cortical myoclonus in a case of HIV‐related encephalopathy
Authors: Canafoglia Laura , Panzica Ferruccio , Franceschetti Silvana , Carriero M. Rita , Ciano Claudia , Scaioli Vidmer , Chiapparini Luisa , Visani Elisa , Avanzini Giuliano
Published: December 2003

We describe a 66‐year‐old, HIV‐seropositive patient presenting with ataxia and upper limb rhythmic myoclonus activated by postural maintenance. Electromyograph (EMG) recordings of the forearm muscles showed 50‐msec bursts, with a frequency of 10 Hz, concurring with frontocentral electroencephalograph (EEG) rhythmic activity. Autoregressive spectral analysis applied to the EEG–EMG traces made it possible to detect significant coherence between the rhythmic EEG discharges and EMG bursts. The amplitude of the middle‐latency somatosensory evoked potentials was increased. Long‐latency reflexes were enhanced. On the basis of the electrophysiological findings, the movement disorder should be considered a rhythmic variant of cortical myoclonus. In our patient, HIV infection may have caused a dysfunction in the central nervous system pathways involving the cerebellum and sensorimotor cortex, similar to that occurring in genetically determined conditions characterised by cortical myoclonus. © 2003 Movement Disorder Society
Phenotypic features of Huntington's disease‐like 2
Authors: Walker Ruth H. , Jankovic Joseph , O'Hearn Elizabeth , Margolis Russell L.
Published: December 2003

Huntington's disease‐like 2 is an autosomal dominantly inherited disorder due to an expansion of trinucleotide repeats. It resembles classic Huntington's disease in clinical phenotype, inheritance pattern, and neuropathological features. We highlight the clinical features of this disorder, including chorea, dystonia, parkinsonism, and cognitive deficits. © 2003 Movement Disorder Society
Chronic treatment with small doses of cabergoline prevents dopa‐induced dyskinesias in parkinsonian monkeys
Authors: Bélanger Nancy , Grégoire Laurent , Tahar Abdallah Hadj , Bédard Paul J.
Published: December 2003

Levodopa continues to be the most effective agent for the symptomatic treatment of Parkinson's disease (PD). But over time, initial benefits decline in efficacy because of a rise in adverse effects such as dyskinesias. The pathophysiology of levodopa‐induced dyskinesias (LID) is not completely understood, but it appears to result from deficient regulation by dopamine of corticostriatal glutamatergic inputs leading to a cascade of neurochemical changes in the striatum and the output pathways. In the present study, we examined if the addition of small doses of cabergoline (a long‐acting D2 receptor agonist) to levodopa could prevent LID. The major hypothesis is that sustained activation of postsynaptic D2 receptors on medium spiny neurons even by small doses of cabergoline could prevent or reduce LID. The minor hypothesis, and the more controversial of the two, is that the long‐acting stimulation by small doses of cabergoline could diminish the release of glutamate by the corticostriatal pathway and prevent LID. Eight MPTP‐treated monkeys with a long‐standing and stable parkinsonian syndrome and having never received dopaminergic agents were used. Two groups of four were treated for 1 month with levodopa/benserazide administered orally (100 mg/25 mg). The second group received in addition a threshold dose of cabergoline (dose ranging from 0.015 to 0.035 mg/kg, SC). During the treatment, we observed LID in the levodopa group but not in the group receiving levodopa+cabergoline. Furthermore, the combination produced a comparable antiparkinsonian effect in terms of quality but prolonged the duration (by 1 to 2 hours) and increased the locomotion (mean for 2 weeks ≅ 104%). Our data suggest that a small dose of a long‐acting D2 agonist combined with high doses of levodopa could be preventive of LID in patients with PD and could be an alternative to using antiglutamatergic agents for this purpose. © 2003 Movement Disorder Society
Epilepsia partialis continua in progressive multifocal leukoencephalopathy: A motor cortex isolation syndrome
Authors: Berciano José , Leno Carlos , Figols Javier , García Antonio , Polo José M. , Berciano María T. , Ariza Aurelio
Published: December 2003

We describe the clinical and neuropathological features in a patient aged 45 years with progressive multifocal leukoencephalopathy with epilepsia partialis continua. The motor cortex and basal ganglia were preserved. Our findings lend support to the notion of isolation of the motor cortex as the cause of this particular type of focal status epilepticus. © 2003 Movement Disorder Society
Parkinson's disease, subthalamic stimulation, and selection of candidates: A pathological study
Authors: Jarraya Bechir , Bonnet Anne‐Marie , Duyckaerts Charles , Houeto Jean‐Luc , Cornu Philippe , Hauw Jean‐Jacques , Agid Yves
Published: December 2003

We report on a patient with Parkinson's disease (PD) who was moderately improved by stimulation of the subthalamic nucleus (STN) and died 2 years after electrode implantation. After neurosurgery, symptoms that had responded to levodopa treatment preoperatively continued to improve. Postural instability, dysarthria, and cognitive impairment continued to worsen, despite STN stimulation and levodopa treatment. Postmortem examination of the brain confirmed the diagnosis of PD and showed that the electrodes had been correctly positioned within the STN. The failure of STN stimulation in this patient confirms the importance of screening and excluding patients from surgery with evolving parkinsonian axial symptoms or cognitive impairment. © 2003 Movement Disorder Society
Subtraction brain SPECT imaging in a patient with gait ignition failure
Authors: Lee Phil Hyu , Lee Jin Soo , Lee Myung Hoon , Lee Jung Doo , Huh Kyoon
Published: December 2003

The precise anatomical location and pathophysiology of gait ignition failure (GIF) is poorly understood. We investigated the cerebral perfusion patterns using subtraction brain single photon emission computed tomography (SPECT) in a patient with GIF. Subtraction brain SPECT imaging revealed an increased activity in the region of right ventrolateral midbrain and ventral medulla. © 2003 Movement Disorder Society
Auditory startle response in cervical dystonia
Authors: Müller Jörg , Kofler Markus , Wenning Gregor K. , Seppi Klaus , Valls‐Solé Josep , Poewe Werner
Published: December 2003

The excitability of brainstem neurons is abnormally enhanced in patients with cervical dystonia (CD), but the extend of such abnormality is not known. We examined whether patients with CD showed abnormalities in the auditory startle response (ASR), a brainstem reflex elicited by an unexpected loud stimulus. Thirteen patients with CD were investigated 3 months after botulinum toxin treatment. Thirteen healthy volunteers served as controls. ASRs were elicited by binaural high‐intensity auditory stimuli. Reflex electromyographic (EMG) activity was recorded simultaneously with surface electrodes bilaterally from masseter, orbicularis oculi, sternocleidomastoid, and biceps brachii muscles. We found that ASR onset latencies were similar for patients and controls. CD patients had significantly lower ASR probabilities than controls (P = 0.007). ASR area under the curve was significantly smaller in CD patients (P = 0.017). Similar to controls, patients showed a significant habituation of ASR (P < 0.001, each); however, CD patients showed a prolonged tonic or phasic EMG activity after the initial ASR that was not observed in controls. Normal latencies and recruitment pattern indicate a preserved organization of intrinsic neural pathways mediating ASR in CD. Reduced ASR probability and magnitude as well as prolonged EMG activity after the proper startle response corroborate and extend previous findings on brainstem dysfunction in CD. © 2003 Movement Disorder Society
Sleep attacks may not be a side effect of dopaminergic medication
Authors: Homann Carl Nikolaus , Homann Barbara , Ott Erwin , Park Kwang B.
Published: December 2003

A reply to this Letter can be found here: Movement Disorders 2003;18(12):1571.
Magnetic resonance spectroscopy of cerebral cortex is normal in hereditary hyperekplexia due to mutations in the GLRA1 gene
Authors: Tijssen Marina A.J. , Brown Peter , MacManus David , McLean Mary A. , Davie Charles
Published: December 2003

Excessive startling and stiffness in hereditary hyperekplexia has been attributed to lack of inhibition at either the cortical or brainstem level. Six patients with hereditary hyperekplexia (HH) and a confirmed mutation in the gene encoding the α1 subunit of the glycine receptor (GLRA1) underwent single voxel 1H magnetic resonance spectroscopy (MRS) of the brainstem and an area of frontal cortex and white matter using a method that allows absolute quantification of metabolites. The results of MRS were within normal limits, although there was a tendency for the neuronal marker N‐acetyl aspartate to be reduced in the brainstem of patients compared with that in controls. Thus, we found no evidence to support a deficit in the cerebral cortex in patients with hereditary hyperekplexia due to mutations in the GLRA1 gene. © 2003 Movement Disorder Society
Dystonia in a patient with ring chromosome 21
Authors: Hou Craig E. , Schlaggar Bradley L. , Racette Brad A.
Published: December 2003

Dystonia associated with chromosomal abnormalities is typically attributed to chromosomal deletions. We describe a patient with ring chromosome 21, with karyotype 46XX,r(21)(p11.2q22.3); 46,XX,dic r(21)(p11.2q22.3); 45, XX, –21, who developed childhood onset cervical dystonia. © 2003 Movement Disorder Society
Deficits induced by quinolinic acid lesion to the striatum in a position discrimination and reversal task are ameliorated by permanent and temporary lesion to the globus pallidus: A potential novel treatment in a rat model of Huntington's disease
Authors: Joel Daphna , Ayalon Liat , Tarrasch Ricardo , Weiner Ina
Published: December 2003

Symptoms in the early stages of Huntington's disease (HD) are assumed to reflect basal ganglia circuit dysfunction secondary to degeneration of striatal projections to the external segment of the globus pallidus (GPe). The hypothesis that GPe lesion would ameliorate HD symptoms by “normalizing” the circuit's functioning was tested in a rat model of this disease. The performance of rats sustaining quinolinic acid lesion to the striatum (a rat model of HD) in a position discrimination and reversal task was compared with the performance of rats sustaining in addition a bilateral excitotoxic lesion to the globus pallidus (GP) carried out simultaneously with the striatal lesion (Experiment 1) or 1 month after the striatal lesion (Experiment 2), as well as a unilateral temporary lesion of the GP (Experiment 3). The striatal lesion‐induced deficit in the task was effectively reversed by a bilateral excitotoxic GP lesion carried out simultaneously or 1 month after the striatal lesion, as well as by a temporary unilateral GP inactivation. Given that a similar dysfunction of basal ganglia circuitry is thought to subserve the behavioral alterations seen in quinolinic acid lesioned rats and some of the symptoms in HD, these results raise the possibility that lesion or inactivation of the GPe may alleviate some of HD symptoms. © 2003 Movement Disorder Society
Stochastic computational modelling of highly heterogeneous poroelastic media with long‐range correlations
Authors: Frias Diego G. , Murad Márcio A. , Pereira Felipe
Published: December 2003

The compaction of highly heterogeneous poroelastic reservoirs with the geology characterized by long‐range correlations displaying fractal character is investigated within the framework of the stochastic computational modelling. The influence of reservoir heterogeneity upon the magnitude of the stresses induced in the porous matrix during fluid withdrawal and rock consolidation is analysed by performing ensemble averages over realizations of a log‐normally distributed stationary random hydraulic conductivity field. Considering the statistical distribution of this parameter characterized by a coefficient of variation governing the magnitude of heterogeneity and a correlation function which decays with a power‐law scaling behaviour we show that the combination of these two effects result in an increase in the magnitude of effective stresses of the rock during reservoir depletion. Further, within the framework of a perturbation analysis we show that the randomness in the hydraulic conductivity gives rise to non‐linear corrections in the upscaled poroelastic equations. These corrections are illustrated by a self‐consistent recursive hierarchy of solutions of the stochastic poroelastic equations parametrized by a scale parameter representing the fluctuating log‐conductivity standard deviation. A classical example of land subsidence caused by fluid extraction of a weak reservoir is numerically simulated by performing Monte Carlo simulations in conjunction with finite elements discretizations of the poroelastic equations associated with an ensemble of geologies. Numerical results illustrate the effects of the spatial variability and fractal character of the permeability distribution upon the evolution of the Mohr–Coulomb function of the rock. Copyright © 2004 John Wiley & Sons, Ltd.
Numerical prediction of blast‐induced stress wave from large‐scale underground explosion
Authors: Wu Chengqing , Lu Yong , Hao Hong
Published: December 2003

This paper presents a numerical model for predicting the dynamic response of rock mass subjected to large‐scale underground explosion. The model is calibrated against data obtained from large‐scale field tests. The Hugoniot equation of state for rock mass is adopted to calculate the pressure as a function of mass density. A piecewise linear Drucker–Prager strength criterion including the strain rate effect is employed to model the rock mass behaviour subjected to blast loading. A double scalar damage model accounting for both the compression and tension damage is introduced to simulate the damage zone around the charge chamber caused by blast loading. The model is incorporated into Autodyn3D through its user subroutines. The numerical model is then used to predict the dynamic response of rock mass, in terms of the peak particle velocity (PPV) and peak particle acceleration (PPA) attenuation laws, the damage zone, the particle velocity time histories and their frequency contents for large‐scale underground explosion tests. The computed results are found in good agreement with the field measured data; hence, the proposed model is proven to be adequate for simulating the dynamic response of rock mass subjected to large‐scale underground explosion. Extended numerical analyses indicate that, apart from the charge loading density, the stress wave intensity is also affected, but to a lesser extent, by the charge weight and the charge chamber geometry for large‐scale underground explosions. Copyright © 2004 John Wiley & Sons, Ltd.
Novel applications of bifacial solar cells
Authors: Hezel Rudolf
Published: December 2003

Utilizing the light reflected by simple means onto the rear surface of solar cells is an effective way of lowering the cost of solar electricity, since more power is generated per cell. Innovative bifacial photovoltaic modules have been introduced, such as a multi‐functional bifacial PV sun‐shading element which is based on bifacially sensitive solar cells in combination with a white semitransparent reflector back sheet. Not only is sunlight collected by its front and rear surface efficiently converted into electricity, but also diffuse glare‐free daylight is provided. Other applications include relatively narrow bifacial modules installed at a certain distance in front of a reflecting background. In all cases power gains of more than 50% can be achieved with little extra cost compared with monofacial modules. Copyright © 2003 John Wiley & Sons, Ltd.
Determination of activation barriers for the diffusion of sodium through CIGS thin‐film solar cells
Authors: Zellner M. B. , Birkmire R. W. , Eser E. , Shafarman W. N. , Chen J. G.
Published: December 2003

We have determined the activation energies of sodium diffusion from the soda‐lime glass substrate through the Mo back‐contact layer, as well as through copper indium gallium diselenide (CIGS) deposited on the Mo back‐contact layer of CIGS thin‐film solar cells. The activation energies were determined by X‐ray photoelectron spectroscopy (XPS) to measure surface sodium concentrations before and after thermally induced diffusion. The activation energies were found to be similar for the diffusion of Na through the Mo/glass and CIGS/Mo/glass thin films, approximately 8·6 and 9·6 kcal/mol, respectively. Furthermore, the sodium diffusion was found to occur by annealing in an environment of 1·0×10−5 Torr of air, oxygen, or water vapor, but not in vacuum of less than 1×10−8 Torr. In addition, the diffusion of Na was found to occur faster in the presence of oxygen than in water under identical annealing conditions. Copyright © 2003 John Wiley & Sons, Ltd.
Improved performance in ZnO/CdS/CuGaSe2 thin‐film solar cells
Authors: Young David L. , Keane James , Duda Anna , AbuShama Jehad A. M. , Perkins Craig L. , Romero Manuel , Noufi Rommel
Published: December 2003

We report the growth and characterization of improved efficiency wide‐bandgap ZnO/CdS/CuGaSe2 thin‐film solar cells. The CuGaSe2 absorber thickness was intentionally decreased to better match depletion widths indicated by drive‐level capacitance profiling data. A total‐area efficiency of 9·5% was achieved with a fill factor of 70·8% and a Voc of 910 mV. Published in 2003 by John Wiley & Sons, Ltd.
Competence, persistence, and success: The positive psychology of behavioral skill instruction
Authors: Martens Brian K. , Witt Joseph C.
Published: December 2003

Early school failure is a critical factor in the development of peer rejection and antisocial behavior in children. This paper describes three sets of instructional strategies that have been shown to promote high levels of academic competence by arranging frequent opportunities for correct skill practice: (a) teaching children at their instructional level and monitoring progress, (b) teaching children differently as their skills improve, and (c) rewarding success and setting goals. Research is reviewed showing that practicing skills to high levels of fluency leads to retention and endurance, the emergence of new forms of a skill, and creative problem solving. The motivation of children to complete academic tasks through the strategic use of reinforcement is discussed, as are the implications of these strategies for encouraging children to be persistent, self‐motivated, life‐long learners. © 2004 Wiley Periodicals, Inc. Psychol Schs 41: 19–30, 2004.
Life satisfaction in children and youth: Empirical foundations and implications for school psychologists
Authors: Huebner E. Scott , Suldo Shannon M. , Smith Laura C. , McKnight Caroline G.
Published: December 2003

A central component of positive psychology is subjective well‐being (SWB). One facet of SWB receiving increased research attention is children's perceived quality of life (PQOL). Existing research related to child and youth PQOL is reviewed, followed by a discussion of the implications of the research for school psychology practice. Research with children and adolescents reveals that PQOL has a wide ranging nomological network including personality, environmental, and activity variables. Furthermore, PQOL appears to mediate relationships between the environmental experiences of youth and problem behavior. Implications are discussed within the context of calls for greater attention by school psychologists to prevention, non‐traditional assessment, direct service, consultation with teachers and parents, diversity issues, and the science‐practice connection. © 2004 Wiley Periodicals, Inc. Psychol Schs 41: 81–93, 2004.
Enhancing subjective well‐being in individuals with asthma
Authors: Bray Melissa A. , Kehle Thomas J. , Peck Heather L. , Theodore Lea A. , Zhou Zheng
Published: December 2003

Asthma, a chronic respiratory disease, is caused by a complex interaction between genetic and environmental variables. The intent of this article is to propose a theory that provides an explanation for the reduction of emotionally triggered asthma through treatments derived from positive psychology. The basic tenet of the theory is that physical health issues, such as asthma, can be promoted through systematic interventions that are designed to enhance the individual's sense of independence, intimacies or friendships, and/or feelings of competence. This theoretical approach is based largely on Bertrand Russell's definition of happiness and is consistent with positive psychology in that it focuses on variables that promote subjective well‐being, or a satisfying daily life. © 2004 Wiley Periodicals, Inc. Psychol Schs 41: 95–100, 2004.
Positive psychology in the prevention of eating disorders
Authors: Steck Erin L. , Abrams Laura M. , Phelps LeAdelle
Published: December 2003

Traditionally the identification of, and treatment for, eating disorders has been based on developmental psychopathology theory and research, thereby emphasizing risk factors and the elimination of maladaptive behaviors. This article seeks to reconceptualize the prevention of, and protective factors for, eating disordered behavior from the positive psychology framework proposed by Seligman and Csikszentmihalyi. This philosophy posits that psychology should strive to identify characteristics relating to positive subjective experiences, constructive individual traits, and affirmative institutions for the purpose of emphasizing and enhancing these strengths. To this end, we present recent literature on promoting protective factors with respect to these variables in the prevention of eating disorders. © 2004 Wiley Periodicals, Inc. Psychol Schs 41: 111–117, 2004.
Integrating positive psychology into schools: Implications for practice
Authors: Terjesen Mark D. , Jacofsky Matthew , Froh Jeffrey , DiGiuseppe Raymond
Published: December 2003

Traditional approaches for working with children and families in the schools focus on problems and disturbance. The concept of positive psychology as a way to change this focus is offered through exploration of its integration within school psychology. Specifically, the application of positive psychology can form the basis of preventive practices within the school setting. Examples of this application are provided within common roles of the school psychologist (consultation, direct work, educational assessment and planning). © 2004 Wiley Periodicals, Inc. Psychol Schs 41: 163–172, 2004.
Activation of the Raf‐1/MEK/Erk kinase pathway by a novel Cdc25 inhibitor in human prostate cancer cells
Authors: Nemoto Kaoru , Vogt Andreas , Oguri Tetsuya , Lazo John S.
Published: December 2003

BACKGROUND

The serine/threonine kinase Raf‐1 is a major regulator of the mitogen activated protein kinase (MAPK) pathway, which has been associated with the progression of prostate cancer to the more advanced and androgen‐independent disease. Cdc25A phosphatase has been implicated in the regulation of Raf‐1 and the MAPK pathway.

METHODS

We used a novel and potent Cdc25A inhibitor, 2,3‐bis‐[2‐hydroxyethylsulfonyl]‐[1,4] naphthoquinone (NSC 95397), and its congener (2‐mercaptoethanol)‐3‐methyl‐1, 4‐naphthoquinone (NSC 672121) to study the role of Cdc25A on the MAPK pathway in human prostate cancer cells.

RESULTS

We found Raf‐1 physically interacted with Cdc25A in PC‐3 and LNCap cells and inhibitors of Cdc25A induced both extracellular signal‐regulated kinase (Erk) activation and Raf‐1 tyrosine phosphorylation. NSC 95397 attenuated Cdc25A and Raf‐1 interactions due to accelerated degradation of Cdc25A, which was mediated by proteasome degradation. The MAPK kinase (MEK) inhibitor U0126 completely inhibited Erk activation by NSC 95397 and NSC 672121.

CONCLUSIONS

These results indicate Cdc25A phosphatase regulates Raf‐1/MEK/Erk kinase activation in human prostate cancer cells. © 2003 Wiley‐Liss, Inc.
De novo sequencing of novel neuropeptides directly from Ascaris suum tissue using matrix‐assisted laser desorption/ionization time‐of‐flight/time‐of‐flight
Authors: Yew Joanne Y. , Dikler Sergei , Stretton Antony O.
Published: December 2003

Direct analysis of tissue by matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) allows for the rapid profiling of biological molecules with minimal loss of sample or degradation and reduced likelihood of chemical modification. However, there are still considerable challenges to overcome due to the complexity of tissue and the low quantity of endogenous peptide in a single cell. These problems are exacerbated in the nematode Ascaris suum because of the small size of individual neurons and the paucity of peptide per cell. In an effort to address these difficulties, the recently developed matrix‐assisted laser desorption/ionization time‐of‐flight/time‐of‐flight (MALDI‐TOF/TOF) technology was used in combination with an on‐target derivatization in order to sequence novel neuropeptides directly from Ascaris nervous tissue. Direct MALDI‐TOF/TOF analysis of Ascaris tissue provided the complete amino acid sequences for a previously characterized neuropeptide as well as for three novel peptides with homologues found in other nematodes. These results demonstrate a method for the rapid characterization of sub‐femtomolar amounts of peptide directly from tissue using MALDI‐TOF/TOF. Copyright © 2003 John Wiley & Sons, Ltd.