bluuebunny/crossref_metadata_2025 huggingface dataset:
Behavioral and biochemical correlates of the dyskinetic potential of dopaminergic agonists in the 6‐OHDA lesioned rat
Authors: Carta Anna R. , Lucia Frau , Annalisa Pinna , Silvia Pontis , Nicola Simola , Nicoletta Schintu , Micaela Morelli
Published: April 2008

Prolonged treatment with L‐DOPA induces highly disabling dyskinesia in Parkinson's disease (PD) patients. In contrast, dopaminergic agonists display variably dyskinetic outcome, depending on pharmacokinetic/pharmacodynamic profile. The present study was aimed at assessing behavioral and biochemical correlates of intense or mild dyskinesia displayed by the different dopamine (DA) receptors stimulation in a rat model of PD. The effect of subchronic stimulation of the D1 receptor by SKF38393, and the D2/D3 receptor by ropinirole was evaluated in unilaterally 6‐hydroxyDA‐lesioned rats. Sensitization of contralateral turning (SCT) behavior and abnormal involuntary movements (AIMs) were assessed as behavioral correlates of dyskinetic responses. Opioid peptides mRNA in the dorsolateral striatum (dlStr) and glutamic acid decarboxylase (GAD67) mRNA content in globus pallidus (GP), were evaluated as an index of neuroadaptive changes occurring in the direct and indirect basal ganglia pathways. Subchronic SKF38393 caused AIMs and SCT whereas ropinirole elicited SCT only, indicating that both drugs induced some dyskinetic response, albeit of different type. Peptides mRNA evaluation in dlStr, showed that SKF38393 subchronic treatment was associated to an overexpression of both dynorphin (DYN) and enkephalin (ENK) mRNAs, in the direct and indirect striatal pathway respectively. In contrast, a decrease in DYN mRNA levels only was observed after treatment with ropinirole. Analysis of GAD67 mRNA levels in the GP showed an increase after both D1 and D2/D3 agonist treatments. Results suggest that presence of SCT alone or SCT plus AIMs might represent correlates of the differential severity of dyskinetic movements induced by treatment with low (ropinirole) or high (SKF38393) dyskinetic potential. Neuroadaptive increases in opioid peptide expression in both direct and indirect striatal pathways were associated to the appearance of AIMs alone. In contrast, increase of GAD67 mRNA in the GP was associated to both behavioral responses (SCT and AIMs), suggesting that neuroadaptive changes in this area were unrelated to the difference in dyskinetic potential of drugs. drugs. Synapse 62:524–533, 2008. © 2008 Wiley‐Liss, Inc.
First‐trimester screening for trisomy 21 by free beta‐human chorionic gonadotropin and pregnancy‐associated plasma protein‐A: impact of maternal and pregnancy characteristics
Authors: Kagan K. O. , Wright D. , Spencer K. , Molina F. S. , Nicolaides K. H.
Published: April 2008

Objectives

To use multiple regression analysis to define the contribution of maternal variables that influence the measured concentration of free beta‐human chorionic gonadotropin (β‐hCG) and pregnancy‐associated plasma protein‐A (PAPP‐A), and the interaction between these covariates, in first‐trimester biochemical screening for trisomy 21.

Methods

This was a multicenter study of prospective screening for trisomy 21 by a combination of fetal nuchal translucency thickness, and maternal serum free β‐hCG and PAPP‐A at 11 + 0 to 13 + 6 weeks of gestation. In the pregnancies subsequently found to have trisomy 21 and in those with no obvious chromosomal abnormality, we used multiple regression analysis to account for pregnancy characteristics that influence the measured concentrations of free β‐hCG and PAPP‐A. We fitted Gaussian distributions to the distribution of log multiples of the median (MoM) values in trisomy 21 and in unaffected pregnancies.

Results

There were 491 cases of trisomy 21 and 96 803 chromosomally normal pregnancies. Compared with values in Caucasian women, those who were parous, non‐smokers and those who conceived spontaneously, PAPP‐A was 57% higher in women of Afro‐Caribbean origin, 3% higher in South Asians, 9% higher in East Asians, 2% higher in nulliparous women, 17% lower in smokers and 10% lower in those conceiving by in‐vitro fertilization (IVF). Free β‐hCG was 12% higher in women of Afro‐Caribbean origin, 9% lower in South Asians, 8% higher in East Asians, 2% higher in nulliparous women, 4% lower in smokers and 9% higher in those conceiving by IVF. In screening for trisomy 21 by maternal age and serum free β‐hCG and PAPP‐A the estimated detection rate was 65% for a false‐positive rate of 5%.

Conclusions

In first‐trimester biochemical screening for trisomy 21 it is essential to adjust the measured values of free β‐hCG and PAPP‐A for maternal and pregnancy characteristics. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Association of isolated short femur in the mid‐trimester fetus with perinatal outcome
Authors: Weisz B. , David A. L. , Chitty L. , Peebles D. , Pandya P. , Patel P. , Rodeck C. H.
Published: April 2008

Objectives

To evaluate the prevalence of fetal isolated short femur in a cohort of women screened for Down syndrome by the integrated test, and to compare the outcome of fetuses with isolated short femur in the mid‐trimester with that of fetuses with normal femur length (controls).

Methods

This was a retrospective cohort study of 1262 women booked for antenatal care and delivery at University College London Hospital. All women had integrated testing in the late first and early second trimesters and a detailed anomaly scan in the mid‐trimester. All scan reports, screening results and neonatal data were analyzed statistically.

Results

The fetal femur was short (< 5th percentile) in 5.1% of patients and 4.7% had isolated short femur. In pregnancies with isolated short femur, the birth weight was significantly lower and there were higher rates of small‐for‐gestational age (SGA) and low birth weight (LBW) infants, compared with controls (P < 0.01). The odds ratios for SGA and LBW in pregnancies with isolated short femur were 3.0 (95% CI, 1.5–5.9) and 2.60 (95% CI, 1.1–6.2), respectively. Isolated short femur was associated significantly with low levels of pregnancy‐associated plasma protein‐A (P = 0.001).

Conclusions

Isolated short femur in the mid‐trimester fetus is associated with fetal growth restriction and SGA. In the context of normal Down syndrome screening and a normal anomaly scan, this marker should be regarded as a predictor for SGA, and fetal growth should be monitored during these pregnancies. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
A series of promoters for constitutive expression of heterologous genes in fission yeast
Authors: Matsuyama Akihisa , Shirai Atsuko , Yoshida Minoru
Published: April 2008

Inducible/repressible promoters are useful for the maintenance of toxic genes or timely expression. For ectopic expression of cloned genes in the fission yeast Schizosaccharomyces pombe, the thiamine‐regulatable nmt1 promoter has been widely used, since the transcriptional activity of this promoter can be controlled by thiamine. However, this property sometimes limits a certain type of research, since the expression inevitably requires cells to be cultivated under the conditions that induce promoter activation. To allow constitutive expression of heterologous genes, we cloned three promoters of cam1+, tif51+ and ef1a‐c+. Construction of a series of vectors comprising these promoters and their introduction into the fission yeast cells demonstrated that the activity was different among these promoters but was not affected by cultured media commonly used in fission yeast. Therefore, a promoter with appropriate strength would be selectable from these promoters, depending on the genes to be expressed. Copyright © 2008 John Wiley & Sons, Ltd.
Flucloxacillin Reduces Stiffness Following Flexor Tendon Repair
Authors: Schumacher Hagen H. A. , James Nick K.
Published: April 2008

To determine the benefit of antibiotic prophylaxis on postoperative mobility in flexor tendon repairs, case notes of 72 flexor tendon injuries in twenty four patients were analyzed retrospectively (2001–2003). Only patients with non-contaminated injuries from sharp instruments in flexor zone 2 were included in the study; 57% were male, average age was 31 years, and 24% were smokers. The majority of injuries were caused by metal blades (45%). Most tendons were repaired with modified Kessler technique (69%). Twenty-five percent received intravenous flucloxacillin or co-amoxiclav perioperatively. Reduced total active motion (TAM, found in 25% of patients more than 7weeks after surgical repair) significantly complicated patients without perioperative intravenous flucloxacillin cover. The use of intravenous perioperative flucloxacillin is a plausible adjunct in surgery to prevent postoperatively reduced mobility.
Volumetric abnormalities associated with cognitive deficits in patients with schizophrenia
Authors: Wolf Robert Christian , Höse Annett , Frasch Karel , Walter Henrik , Vasic Nenad
Published: April 2008

While functional neuroimaging studies on attention and executive function in schizophrenia have reported several functionally aberrant cortical regions, less is known about the relationship of cognitive impairment and regional volume alterations. In order to investigate the relationship between cognitive impairment and structural alterations, we studied healthy control subjects and partially remitted, medicated inpatients with DSM-IV schizophrenia using voxel-based morphometry (VBM) and a standardised neuropsychological test battery. Schizophrenic patients showed reduced grey matter (GM) density in the bilateral temporal cortex, the left inferior parietal lobule, the cingulate gyrus and the left middle frontal gyrus. Reduced GM volume was additionally found in the left hippocampal gyrus and the right superior frontal cortex. Reduced white matter density was found in the posterior corpus callosum. Structure-cognition regression analyses revealed that decreased GM density of the left inferior parietal and the right middle temporal cortex was associated with worse performance during divided attention. Worse performance during the spatial span was associated with volumetric abnormalities of the hippocampal gyrus. These results indicate that regional abnormalities in brain structure may offer an account for some impaired cognitive domains in patients with schizophrenia, while other cognitive domains may remain relatively less affected by volumetric alterations.
Stability and treatment outcome of distinct classes of mania
Authors: van Rossum Inge , Haro Josep Maria , Tenback Diederik , Boomsma Maarten , Goetz Iris , Vieta Eduard , van Os Jim ,   for the EMBLEM Advisory Board
Published: April 2008

Background

Psychopathological heterogeneity in manic syndromes may in part reflect underlying latent classes with characteristic outcome patterns. Differential treatment course and outcome after 12 weeks of treatment were examined for three distinct classes of patients with acute mania in bipolar disorder.

Subjects and methods

Three thousand four hundred and twenty-five patients with acute mania were divided into three distinct mania classes: ‘Typical’, ‘Psychotic’ and ‘Dual’ (i.e. comorbid substance use) mania. Persistence of class differences and social outcomes were examined, using multilevel regression analyses and odds ratios.

Results

The three classes showed substantial stability post-baseline in the pattern of associations with class-characteristic variables. Psychotic and Dual mania predicted poorer outcome in terms of psychosis comorbidity and overall bipolar and mania severity, while Dual mania additionally predicted poorer outcome of alcohol and substance abuse. Worse social outcomes were observed for both Dual and Psychotic mania.

Conclusion

The identified distinct classes are stable and associated with differential treatment outcome. Overall, Dual and Psychotic mania show less favourable outcomes compared to Typical mania. These findings additionally give rise to concern on the generalisability of randomized clinical trials RCTs.
Crystal structure of the Ca2+‐form and Ca2+‐binding kinetics of metastasis‐associated protein, S100A4
Authors: Gingras Alexandre R. , Basran Jaswir , Prescott Andrew , Kriajevska Marina , Bagshaw Clive R. , Barsukov Igor L.
Published: April 2008

S100A4 takes part in control of tumour cell migration and contributes to metastatic spread in in vivo models. In the active dimeric Ca2+‐bound state it interacts with multiple intracellular targets. Conversely, oligomeric forms of S100A4 are linked with the extracellular function of this protein. We report the 1.5 Å X‐ray crystal structure of Ca2+‐bound S100A4 and use it to identify the residues involved in target recognition and to derive a model of the oligomeric state. We applied stopped‐flow analysis of tyrosine fluorescence to derive kinetics of S100A4 activation by Ca2+ (k
on
= 3.5 μM−1
s−1, k
off
= 20 s−1).
The CTD role in cotranscriptional RNA processing and surveillance
Authors: de Almeida Sérgio F. , Carmo-Fonseca Maria
Published: April 2008

In higher eukaryotes, the production of mature messenger RNA that exits the nucleus to be translated into protein requires precise and extensive processing of the nascent transcript. The processing steps include 5′‐end capping, splicing, and 3′‐end formation. Pre‐mRNA processing is coupled to transcription by mechanisms that are not well understood but involve the carboxyl‐terminal domain (CTD) of the largest subunit of RNA polymerase II. This review focuses on recent findings that provide novel insight into the role of the CTD in promoting RNA processing and surveillance.
Spectroscopic and photochemical analysis of proteorhodopsin variants from the surface of the Arctic Ocean
Authors: Jung Jae Yong , Choi Ah Reum , Lee Yoo Kyung , Lee Hong Kum , Jung Kwang-Hwan
Published: April 2008

Proteorhodopsin (PR), a retinal‐containing seven transmembrane helix protein, functions as a light‐driven proton pump. Using PCR, we isolated 18 PR variants originating from the surface of the Arctic Ocean. Their absorption maxima were between 517 and 546 nm at pH 7. One of the isolates turned out to be identical to GPR (green light‐absorbing proteorhodopsin) from Monterey Bay. Interestingly, 10 isolates had replaced a tyrosine in the retinal‐binding site (Tyr200 in GPR) with Asn. They showed a slower photocycle, more blue‐shifted absorption maxima at pH 10, and relatively larger ΔH and ΔS of activation of the transition between the O intermediate and the ground state compared to GPR.
Increased abundance of cytoplasmic and nuclear caveolin 1 in human diploid fibroblasts in H2O2‐induced premature senescence and interplay with p38αMAPK
Authors: Chrétien Aline , Piront Neil , Delaive Edouard , Demazy Catherine , Ninane Noëlle , Toussaint Olivier
Published: April 2008

Treatment of IMR‐90 human diploid fibroblasts with a sublethal concentration of H2O2 induces premature senescence. We investigated the protein abundance, subcellular localization and involvement of caveolin 1 in premature senescence. Caveolin 1 is a scaffolding protein able to concentrate and organize signaling molecules within the caveolae membrane domains. We report the first evidence of increased nuclear and cytoplasmic localization of caveolin 1 during establishment of H2O2‐induced premature senescence. Moreover, we demonstrate that phosphorylation of caveolin 1 during treatment with H2O2 is dependent on p38α mitogen‐activated protein kinase.
Comparison of costs of care between patients with Alzheimer's disease and dementia with Lewy bodies
Authors: Zhu Carolyn W. , Scarmeas Nikolaos , Stavitsky Karina , Albert Marilyn , Brandt Jason , Blacker Deborah , Sano Mary , Stern Yaakov
Published: April 2008

Background

The objective of this study was to compare total costs of care and its major components for community‐living patients with Alzheimer's disease (AD) or dementia with Lewy bodies (DLB). This cross‐sectional analysis of baseline data from the Predictors II Study took place in three university‐based AD centers in the U.S.

Methods

Community‐living patients clinically diagnosed with probable AD (n = 170) or DLB (n = 25) with a modified Mini‐Mental State examination (mMMS) score ≥30, equivalent to a score of approximately ≥16 on the Folstein Mini‐Mental State Examination (MMSE), participated in this study. Patient and informant reported on patients' use of direct medical care, direct nonmedical care, and informal care. Patients' clinical and demographic characteristics included global cognitive status (measured by MMSE), functional capacity (measured by Blessed Dementia Rating Scale), psychotic symptoms, behavioral problems, depressive symptoms, extrapyramidal signs, comorbidities, age, and sex. Costs were compared by using covariate matching methods.

Results

Unadjusted total costs and direct medical costs were not significantly different between AD and DLB patients. Compared with AD patients, unadjusted indirect costs were significantly higher and unadjusted direct nonmedical costs were significantly lower among DLB patients. After adjusting for age, sex, cognitive and functional status, differences in all cost components between DLB and AD patients were no longer statistically significant.

Conclusions

Apparent cost differences were largely attributed to differences in patients' cognitive and functional status. However, the small sample size for DLB patients might have limited power to detect statistically significant differences in costs of care between these groups.
Racial and seasonal differences in 25-hydroxyvitamin D detected in maternal sera frozen for over 40 years
Authors: Bodnar Lisa M. , Catov Janet M. , Wisner Katherine L. , Klebanoff Mark A.
Published: April 2008

Serum banks from large, decades-old epidemiological studies provide a valuable opportunity to explore the contributions ofin uterovitamin D exposure to fetal origins of adult diseases. We compared 25-hydroxyvitamin D (25(OH)D) by race and season (two powerful predictors of vitamin D status) in sera frozen for ≥  40 years with sera frozen for ≤  2 years to determine whether 25(OH)D is stable enough to test vitamin D-related hypotheses. Data and sera came from seventy-nine pregnant women at 29–32 weeks' gestation in the Boston Collaborative Perinatal Project (CPP; 1959–66) and 124 women at 20–36 weeks' gestation in a 2003–2006 Pittsburgh cohort study. Multivariable linear regression models were used to test main and joint effects of race and season after confounder adjustment. In both cohorts, serum 25(OH)D levels were lower among black than white women (CPP 33·3v.46·7 nmol/l,P < 0·01; Pittsburgh 47·1v.89·6 nmol/l;P < 0·0001) and in winter than summer (CPP 32·7v.47·6 nmol/l,P < 0·0001; Pittsburgh 66·7v.89·8 nmol/l,P < 0·001), with no evidence of a race × season interaction in either cohort. Differences remained significant after confounder adjustment. When CPP and Pittsburgh results were compared, there was no significant difference in the race or season effects. The similarity in the relative change in 25(OH)D in these cohorts by two powerful predictors of vitamin D status suggests that, even if 25(OH)D deteriorated somewhat, it did so similarly across samples. Therefore, trends could be obtained from the decades-old serum data that would be relevant in exploring vitamin D-related hypotheses in future studies.
K-richterite–olivine–phlogopite–diopside–sanidine lamproites from the Afyon volcanic province, Turkey
Authors: AKAL CÜNEYT
Published: April 2008

Middle Miocene volcanic activity in the Afyon volcanic province (eastern part of Western Anatolia) is characterized by multistage potassic and ultrapotassic alkaline volcanic successions. The volcanism is generally related to the northward subduction of the African plate beneath the Eurasian Plate. In Afyon, the Middle Miocene volcanic products consist of melilite leucitite, tephriphonolite, trachyte, basaltic–trachyandesite, phonolite, phonotephrite, tephriphonolite and lamproite rocks. Near-surface emplacement and relatively quiescent subaerial eruptions of lamproitic magma produced different emplacement forms such as dome/plug-shaped bodies and lava flows, showing variation in volume and texture. The mineralogical constituents of the lamproites are sanidine, olivine (77 < Mg no. < 81), phlogopite (74 < Mg no. < 78), K-richterite, clinopyroxene (74 < Mg no. < 78), with accessory apatite, calcite and opaque minerals. Afyon lamproites resemble Mediterranean-type Si-rich lamproites. Their compositional range is 50–52 wt% SiO2, 4–8 wt% MgO, and they display a typical lamproitic affinity. Chondrite-normalized REE patterns exhibit enrichment in LREE relative to HREE ((La/Yb)CN=15.3–17.0). They show extreme enrichment in LILE relative to primitive mantle values and troughs of Nb and Ti. The lamproites give a range of high initial87Sr/86Sr ratios and low143Nd/144Nd ratios. The geochemical and isotopic characteristics suggest that lamproitic magma is derived from highly metasomatized mantle. The enrichment history may include metasomatic events related to subduction, as in other active orogenic areas of the Mediterranean.
CONSTRUCTING AVATIME: QUESTIONS OF HISTORY AND IDENTITY IN A WEST AFRICAN POLITY,c. 1690s TO THE TWENTIETH CENTURY
Authors: BRYDON LYNNE
Published: April 2008

Small-scale societies, like Avatime in eastern Ghana, established, maintained and developed themselves in a range of ways, in spaces between large, centralized states, in West Africa in the precolonial era. This essay demonstrates the inclusivity and initiative (in terms of both economic entrepreneurship andbricolage) of this small group before its effective destruction by Asante in about 1870, and looks at the ways in which Avatime was reconstructed in the last third of the nineteenth century. In addition, issues of ethnicity and identity are broadly addressed, comparing Avatime's inclusivity with tropes of difference discussed in recent studies of small-scale societies in this journal.
THE STATE OF THE SUBJECT: A GUINEAN EDUCATOR'S ODYSSEY IN THE POSTCOLONIAL FOREST, 1960–2001
Authors: STRAKER JAY
Published: April 2008

Recent research on twentieth-century Africa has been marked by a surge of interest in autobiographical narrative. While this development is generally praiseworthy, the knowledge it has produced has been uneven, in temporal as well as spatial terms. This article channels the current interest in personal experience and narrative to a place and time where resonances of the ‘common’ voice have been rather weak: the Republic of Guinea, across the final decades of the twentieth century. Foregrounding the autobiographical reflections of a local teacher in the country's southeastern forest region, it forges new perspectives on political subjectivity in Guinea's understudied provinces.
Adult cystic hygroma: successful use of OK-432 (Picibanil®)
Authors: Woolley S L , Smith D R K , Quine S
Published: April 2008

Objective:

We report an adult case of cystic lymphangioma treated with OK-432 (Picibanil®).

Method:

A case report and review of the literature concerning the use of OK-432 to treat cystic lymphangioma is presented.

Results:

A 31-year-old woman developed a cystic lymphangioma four weeks post-partum. This was treated initially by aspiration, for diagnostic purposes. Investigation suggested that surgery would be challenging. A review of the literature demonstrated success with OK-432 in the treatment of this condition, although primarily in the paediatric population. This patient was successfully treated thus, and at the time of writing remained symptom free. A suggested management plan is outlined.

Conclusion:

Treatment with OK-432 is useful in the management of cystic lymphangiomas in adults and should be considered as first line treatment.
Diphtheria: a case report
Authors: Khodaei I , Sinha A , Dingle A
Published: April 2008

Objective:

We report a case of diphtheria in an elderly patient, with a fatal outcome.

Method:

Case report and a review of the literature concerning the current recommended guidelines on detection of, and response to, diphtheria.

Results:

Although still rare, cases of diphtheria are being reported with increasing frequency in the UK, possibly as a result of immigration and travel. A high index of suspicion, rapid detection of carriers, and instigation of treatment and vaccination are the mainstays of management.

Conclusion:

Diphtheria can mimic other forms of acute upper airway obstruction and can lead to a fatal outcome. Otorhinolaryngological surgeons need to consider this re-emergent disease as a potential diagnosis in patients with an unusual presentation of airway obstruction.
Lasers for inertial confinement fusion driven by high explosives
Authors: Winterberg F.
Published: April 2008

Proposed laser fusion power plant concepts suffer from the huge size and expense of the lasers needed for compression and ignition. In a 1969 study (classified in 1970 and declassified in 2007), the idea to use chemical high explosives for the pumping of megajoule lasers was explored. Apart from being less expensive by orders of magnitude, such lasers are expected to be much more compact, and with their large energy, output could simultaneously drive several thermonuclear micro-explosion chambers. Because of its topical importance, I accepted the journal's invitation to publish a previously classified work, but with new unpublished ideas, with the previously classified paper put into the appendix.
Implosion symmetry of laser-irradiated cylindrical targets
Authors: Ramis R. , Ramírez J. , Schurtz G.
Published: April 2008

We consider the symmetry of cylindrical implosions of laser targets with parameters corresponding to experiments proposed for the LIL laser facility at Bordeaux: eight laser beams in octahedrical configuration, delivering a total of 50 kJ of 0.35 µm laser light in 5 ns, impinging on 1.26 mm diameter polystyrene cylindrical shells filled with deuterium at 30 bar and 5.35 mg cm−3; this configuration allows to place diagnostics along the symmetry axis to evaluate directly the uniformity of implosion. Numerical studies have been carried out by using the hydrodynamic computer codes MULTI and CHIC, including one-dimensional, and two-dimensional R–Z and R–θ simulations. Deuterium is compressed into a 1 mm long and 50 µm diameter filament, with density ranging from 2 to 6 g cm−3 and temperatures above 1000 eV. In spite of the reduced numbers of beams, a good symmetry can be achieved with a careful choice of the irradiation pattern. The heat transport smoothing between laser absorption zone and ablation layer plays a fundamental role in the attenuation of residual non-uniformities. Also, it has been found that the radiation transport determines the radial structure of the compressed filament.
Uncoupled actuation of overconstrained 3T-1R hybrid parallel manipulators
Authors: Lee Chung-Ching , Hervé Jacques M.
Published: April 2008

Based on the Lie-group-algebraic properties of the displacement set and intrinsic coordinate-free geometry, several novel 4-dof overconstrained hybrid parallel manipulators (HPMs) with uncoupled actuation of three spatial translations and one rotation (3T-1R) are proposed. In these HPMs, three limbs are those of Cartesian translational parallel mechanisms (CTPMs) and the fourth limb includes an Oldham-type constant velocity shaft coupling (CVSC). The Lie subgroup of Schoenflies (X) displacements of the displacement Lie group and its mechanical generators with nine categories of their general architectures are recalled. A comprehensive enumeration of all possible Oldham-type CVSC limbs is derived fromX-motion generators. Their constant velocity (CV) transmissions are verified by group-algebraic approach. Then, combining one CTPM and one CVSC, we synthesize a lot of uncoupled 3T-1R overconstrained HPMs, which are classified into nine distinct classes of general architectures. In addition, all possible architectures with at least one hinged parallelogram or with one cylindrical pair are disclosed too. At last, related non-overconstrained HPMs are attained by the addition of one idle pair in each limb of the previous HPMs.
Generating basic skills reports for low-skilled readers
Authors: WILLIAMS SANDRA , REITER EHUD
Published: April 2008

We describe SkillSum, a Natural Language Generation (NLG) system that generates a personalised feedback report for someone who has just completed a screening assessment of their basic literacy and numeracy skills. Because many SkillSum users have limited literacy, the generated reports must be easily comprehended by people with limited reading skills; this is the most novel aspect of SkillSum, and the focus of this paper. We used two approaches to maximise readability. First, for determining content and structure (document planning), we did not explicitly model readability, but rather followed a pragmatic approach of repeatedly revising content and structure following pilot experiments and interviews with domain experts. Second, for choosing linguistic expressions (microplanning), we attempted to formulate explicitly the choices that enhanced readability, using a constraints approach and preference rules; our constraints were based on corpus analysis and our preference rules were based on psycholinguistic findings. Evaluation of the SkillSum system was twofold: it compared the usefulness of NLG technology to that of canned text output, and it assessed the effectiveness of the readability model. Results showed that NLG was more effective than canned text at enhancing users' knowledge of their skills, and also suggested that the empirical ‘revise based on experiments and interviews’ approach made a substantial contribution to readability as well as our explicit psycholinguistically inspired models of readability choices.
Enzymic Thin Film Coatings for Bioactive Materials
Authors: Tong Xiaodong , Trivedi Archana , Jia Hongfei , Zhang Minjuan , Wang Ping
Published: April 2008

Bioactive materials have been explored for a broad range of applications including biocatalysts, biosensors, antifouling membranes and other functional and smart materials. We report herein a unique method for preparation of bioactive materials through a spin coating process. Specifically, we investigated the preparation of protease Subtilisin Carlsberg‐coated plastic films and examined their activities for hydrolysis of chicken egg albumin (CEA). The process generated enzymic coatings with a typical loading of 13 μg/cm2, retaining 46% of the enzyme activity for hydrolysis of CEA in aqueous solutions. Interestingly, the surface‐coated protease thin film not only catalyzed the hydrolysis of CEA in aqueous solutions, but also showed good activity for solid‐state CEA that was coated on top of the enzyme thin film.
Abrupt changes in air temperature and precipitation: Do they matter for water chemistry?
Authors: Temnerud J. , Weyhenmeyer G. A.
Published: April 2008

We analyzed 120 years long time series of air temperature and precipitation from 29 respective 44 sites distributed all over Sweden and determined abrupt changes by using three methods. For air temperature we found significant changes in 1930 and 1989 and for precipitation in 1920, 1979, and 1998. Analyzing more than 30 yearlong time series of ice cover (333 sites), discharge and watercourses chemistry (87 sites), we observed abrupt changes in 1977, 1989, and 1998 for discharge but first in 1998 for watercourses chemistry, most pronounced for organic matter and sulfate concentrations. We suggest that the abrupt increase in air temperature in 1989 liberated more easily mobilized organic matter in the catchments, which, for water chemistry, was first detected in 1998 as a consequence of increased discharge. We conclude that increases in air temperatures can make ecosystems more sensitive to further changes in precipitation.
Theory and simulation of the generation of whistler‐mode chorus
Authors: Omura Yoshiharu , Katoh Yuto , Summers Danny
Published: April 2008

The generation process of whistler‐mode chorus emissions is analyzed by both theory and simulation. Driven by an assumed strong temperature anisotropy of energetic electrons, the initial wave growth of chorus is linear. After the linear growth phase, the wave amplitude grows nonlinearly. It is found that the seeds of chorus emissions with rising frequency are generated near the magnetic equator as a result of a nonlinear growth mechanism that depends on the wave amplitude. We derive the relativistic second‐order resonance condition for a whistler‐mode wave with a varying frequency. Wave trapping of resonant electrons near the equator results in the formation of an electromagnetic electron hole in the wave phase space. For a specific wave phase variation, corresponding to a rising frequency, the electron hole can form a resonant current that causes growth of a wave with a rising frequency. Seeds of chorus elements grow from the saturation level of the whistler‐mode instability at the equator and then propagate away from the equator. In the frame of reference moving with the group velocity, the wave frequency is constant. The wave amplitude is amplified by the nonlinear resonant current, which is sustained by the increasing inhomogeneity of the dipole magnetic field over some distance from the equator. Chorus elements are generated successively at the equator so long as a sufficient flux of energetic electrons with a strong temperature anisotropy is present.
The influence of magnetospheric substorms on SuperDARN radar backscatter
Authors: Wild J. A. , Grocott A.
Published: April 2008

The SuperDARN ionospheric radar network is a leading tool for investigating the near‐Earth space environment. However, reductions in ionospheric backscatter have been reported during magnetospheric substorms. We have therefore investigated the impact of substorms upon SuperDARN backscatter during 3005 substorms and find that the global level of scatter maximizes just prior to substorm onset. In the nightside ionosphere, backscatter poleward of ∼70° magnetic latitude is reduced, with radar echoes shifting to lower latitudes. An examination into the frequency‐dependence of nightside backscatter evolution during substorms reveals that although most backscatter data is based upon operations in the 08–14 MHz range, higher operating frequencies may offer improved performance in the period just prior to and immediately following expansion phase onset. We suggest that the SuperDARN array of high‐frequency coherent‐scatter radars, and in particular those radars with the ability to simultaneously operate at dual frequencies, will play a key role in future space‐ and ground‐based studies of substorms.
Crustal structure and apparent tectonic underplating from receiver function analysis in South Island, New Zealand
Authors: Spasojević Sonja , Clayton Robert W.
Published: April 2008

We utilize seismic converted phases on more than 700 receiver functions calculated for 42 stations in the South Island, New Zealand, to infer crustal and uppermost mantle structure. We determine the crustal thickness from direct observations of conversion from the Moho interface and infer zone of the maximum thickness being located along the axis of the Southern Alps, just east from the Alpine fault. The crustal root widens from north to south in the direction perpendicular to the Alpine fault and appears to have an asymmetric structure. Stations in the alpine portion of island show evidence for prominent midcrustal conversions. Significant crustal thickening is developed in response to both the convergent component of the motion on the Alpine fault and subduction in the Fiordland region. We propose two models for a strong uppermost mantle conversion that occurs at depths between 33 and 83 km on 16 stations and forms a large continuous feature along the east coast and in the central portions of the South Island. Our preferred model attributes upper mantle conversion to tectonically underplated oceanic crust formed by late Oligocene‐Miocene spreading between the Australian and Pacific plates, which was detached from the Australian plate and tectonically underplated under the South Island. An alternative model attributes the upper mantle conversions to long‐lived seismic fabric created by subduction of the Gondwanaland margin.
Future prediction of surface ozone over east Asia using Models‐3 Community Multiscale Air Quality Modeling System and Regional Emission Inventory in Asia
Authors: Yamaji Kazuyo , Ohara Toshimasa , Uno Itsushi , Kurokawa Jun‐ichi , Pochanart Pakpong , Akimoto Hajime
Published: April 2008

Present and future tropospheric ozone (O3) concentrations over east Asia have been simulated by the Models‐3 Community Multiscale Air Quality Modeling System (CMAQ) coupled with the Regional Emission Inventory in Asia (REAS) to predict surface O3 variations caused by future anthropogenic emissions changes. For future prediction, REAS provides three emission scenarios for China (the reference (REF), the policy succeed case (PSC), and the policy failure case (PFC) scenarios) and one emission scenario (the REF scenario) for the other countries. Simulated O3 concentration in summer was relatively high (70–80 ppbv in June and 65–75 ppbv in August) over the North China Plain in 2000. The projected REF emissions for 2020 (2020REF) enhance the monthly averaged O3 to 75–90 ppbv in June and 75–85 ppbv in August. The projected PSC emissions for 2020 (2020PFC), including a slight NOx reduction of –0.2 Tg (–2%) and a large NMVOC increase of 14.3 Tg (97%) for total Chinese emissions during 2000–2020, cause the monthly and annually averaged O3 concentrations to decrease by less than 2 ppbv in northeastern and central China. Over the North China Plain, the projected PFC emissions for 2020 (2020PFC) cause significant increases, more than 20 ppbv in the monthly averaged O3, and the O3 will be 85–105 ppbv in June and 80–95 ppbv in August for 2020. The 2020PFC also affect O3 increases in early summer in South Korea (14–18 ppbv increase for monthly average) and Japan (2–14 ppbv increase for monthly average) during 2000–2020 despite the slight NOx increase of 0.4 Tg (25%) in South Korea and the slight NOx reduction of –0.2 Tg (–10%) in Japan during 2000–2020. The pollutant in these regions seems to be transport from upwind source regions. These experiments show that over central eastern China at midday in June, the O3 concentration is largely affected by NOx emission increases but is insensitive to NMVOC emission increases.
Synchronizing ice cores from the Renland and Agassiz ice caps to the Greenland Ice Core Chronology
Authors: Vinther B. M. , Clausen H. B. , Fisher D. A. , Koerner R. M. , Johnsen S. J. , Andersen K. K. , Dahl‐Jensen D. , Rasmussen S. O. , Steffensen J. P. , Svensson A. M.
Published: April 2008

Four ice cores from the Agassiz ice cap in the Canadian high arctic and one ice core from the Renland ice cap in eastern Greenland have been synchronized to the Greenland Ice Core Chronology 2005 (GICC05) which is based on annual layer counts in the DYE‐3, GRIP and NGRIP ice cores. Volcanic reference horizons, seen in electrical conductivity measurements (ECM) have been used to carry out the synchronization throughout the Holocene. The Agassiz ice cores have been matched to the NGRIP ice core ECM signal, while the Renland core has been matched to the GRIP ice core ECM signal, thus tying the cores to GICC05. Furthermore, it has been possible to synchronize the Renland ice core to NGRIP‐GICC05 in the glacial period back to 60,000 years b2k (years before A.D. 2000), on the basis of a matching of transitions between stadials and interstadials. This work brings the total number of ice core records that have been rigorously tied to the GICC05 timescale up to nine. Renland annual layer thicknesses are increasing with depth during the period from 7 to 8.5 ka b2k, a highly unusual observation only matched by a similar thickness increase in the glacial section of the Renland core some 60 ka ago. Annual layer thicknesses in the Agassiz ice cores point to a well‐developed Raymond bump in the Agassiz ice cap.
Thickness of the magnetic crust of Mars
Authors: Voorhies Coerte V.
Published: April 2008

To estimate the thickness of the magnetic crust of Mars, six observational magnetic spectra are fitted with the theoretical spectrum expected from a novel, bimodal distribution of magnetic sources. Observational spectra differ, for each comes from a different map or model of variously selected and analyzed Mars Global Surveyor Magnetometer/Electron Reflectometer measurements of the vector magnetic field around Mars. The new theoretical spectrum represents fields from both compact sources and extended, laterally correlated sources on a spherical shell, so the estimated shell depth can now be doubled to obtain layer thickness. This typical magnetic crustal thickness is put at 47.8 ± 8.4 km. The extensive sources are enormous, typically 650 km across, and account for over half the magnetic energy at low degrees. There is some indication that these sources are relatively shallow, but the typical area remains about 330,000 km2. Granted such extended sources represent magnetization of Mars’ ancient crust in a core source field dominated by a reversing, areocentric paleodipole, each one arguably formed during a single polarity chron. How did such vast regions of magnetic crust form? A survey of many eligible mechanisms suggests magnetization of cooling igneous rock at minimal rates of about 1 to 0.1 km3/a during superchrons of order 15 to 150 Ma long.
A mechanistic treatment of the dominant soil nitrogen cycling processes: Model development, testing, and application
Authors: Maggi F. , Gu C. , Riley W. J. , Hornberger G. M. , Venterea R. T. , Xu T. , Spycher N. , Steefel C. , Miller N. L. , Oldenburg C. M.
Published: April 2008

The development and initial application of a mechanistic model (TOUGHREACT‐N) designed to characterize soil nitrogen (N) cycling and losses are described. The model couples advective and diffusive nutrient transport, multiple microbial biomass dynamics, and equilibrium and kinetic chemical reactions. TOUGHREACT‐N was calibrated and tested against field measurements to assess pathways of N loss as either gas emission or solute leachate following fertilization and irrigation in a Central Valley, California, agricultural field as functions of fertilizer application rate and depth, and irrigation water volume. Our results, relative to the period before plants emerge, show that an increase in fertilizer rate produced a nonlinear response in terms of N losses. An increase of irrigation volume produced NO2− and NO3− leaching, whereas an increase in fertilization depth mainly increased leaching of all N solutes. In addition, nitrifying bacteria largely increased in mass with increasing fertilizer rate. Increases in water application caused nitrifiers and denitrifiers to decrease and increase their mass, respectively, while nitrifiers and denitrifiers reversed their spatial stratification when fertilizer was applied below 15 cm depth. Coupling aqueous advection and diffusion, and gaseous diffusion with biological processes, closely captured actual conditions and, in the system explored here, significantly clarified interpretation of field measurements.
Use of Acute Hyperphenylalaninemia in Rhesus Monkeys to Examine Sensitivity and Stability of the l-[1-11C]Leucine Method for Measurement of Regional Rates of Cerebral Protein Synthesis with Pet
Authors: Smith Carolyn B , Schmidt Kathleen C , Bishu Shrinivas , Channing Michael A , Bacon Jeff , Burlin Thomas V , Qin Mei , Liu Zhong-hua , Xia Zengyan , Huang Tianjiang , Vuong Bee-Kee , Herscovitch Peter
Published: April 2008

We have previously shown by direct comparison with autoradiographic and biochemical measurements that the l-[1-11C]leucine positron emission tomography method provides accurate determinations of regional rates of cerebral protein synthesis (rCPS) and the fraction (Λ) of unlabeled leucine in the precursor pool for protein synthesis derived from arterial plasma. In this study, we examine sensitivity of the method to detect changes in Λ and stability of the method to measure rCPS in the face of these changes. We studied four isoflurane-anesthetized monkeys dynamically scanned with the high resolution research tomograph under control and mild hyperphenylalaninemic conditions. Hyperphenylalaninemia was produced by an infusion of phenylalanine that increased plasma phenylalanine concentrations three- to five-fold. In phenylalanine-infused monkeys, plasma leucine concentrations remained relatively constant, but values of Λ were statistically significantly decreased by 11% to 15%; rCPS was unaffected. Effects on Λ are consistent with competitive inhibition of leucine transport by increased plasma phenylalanine. The effect on Λ shows that competition for the transporter results in a reduction in the fraction of leucine in the precursor pool for protein synthesis coming from plasma. Even under these hyperphenylalaninemic conditions, rCPS remains unchanged due to the compensating increased contribution of leucine from protein degradation to the precursor pool.
Muscle‐associated Triglyceride Measured by Computed Tomography and Magnetic Resonance Spectroscopy
Authors: Larson‐Meyer D. Enette , Smith Steven R. , Heilbronn Leonie K. , Kelley David E. , Ravussin Eric , Newcomer Bradley R. ,   The Look AHEAD Adipose Research Group
Published: April 2008

Objective: Muscle triglyceride can be assessed in vivo using computed tomography (CT) and 1H magnetic resonance spectroscopy (MRS), two techniques that are based on entirely different biophysical principles. Little is known, however, about the cross‐correlation between these techniques and their test—retest reliability.

Research Methods and Procedures: We compared mean muscle attenuation (MA) in soleus and tibialis anterior (TA) muscles measured by CT with intra‐ and extramyocellular lipids (IMCL and EMCL, respectively) measured by MRS in 51 volunteers (26 to 72 years of age, BMI = 25.5 to 39.3 kg/m2). MA of midthighs was also measured in a subset (n = 19). Test—retest measurements were performed by CT (n = 6) and MRS (n = 10) in separate sets of volunteers.

Results: MA of soleus was significantly associated with IMCL (r = −0.64) and EMCL, which by multiple regression analysis was explained mostly by IMCL (p < 0.001) rather than EMCL (β = −0.010, p = 0.94). Muscle triglyc‐eride was lower in TA than in soleus, and MA of TA was significantly correlated with EMCL (r = −0.40) but not IMCL (r = −0.16). By CT, MA of midthighs was correlated with MA in soleus (r = 0.40, p = 0.07) and whole calf (r = 0.62, p < 0.05). Finally, both MA and IMCL were highly reliable in soleus (coefficient of variation = <2% and 6.7%, respectively) and less reliable in TA (4% and 10%, respectively).

Discussion: These results support the use of both CT and MRS as reliable methods for assessing skeletal muscle lipid.
Lifetime Weight Patterns in Male Physicians: The Effects of Cohort and Selective Survival
Authors: Barone Bethany B. , Clark Jeanne M. , Wang Nae‐Yuh , Meoni Lucy A. , Klag Michael J. , Brancati Frederick L.
Published: April 2008

Objective: The natural history of lifetime weight change is not well understood because of conflicting evidence from cross‐sectional and longitudinal studies. Cross‐sectional analyses find that adult weight is highest at ∼60 years of age and lower thereafter. Longitudinal analyses have not found this pattern. Our objective was to test whether cohort effects and selective survival may explain the differences observed between cross‐sectional and longitudinal studies.

Research Methods and Procedures: We analyzed data on white men from the Johns Hopkins Precursors Study (n = 1197). Weight and height were measured at enrollment during medical school. The Precursors Study collected subsequent weight measurements by self‐report and follows all participants for mortality.

Results: In preliminary analyses that ignored cohort and survival effects, average weight increased 0.16 kg/yr to age 65 (p < 0.001) and declined 0.10 kg/yr thereafter (p = 0.002). When controlling for differing rates of weight change by cohort and survival group, the apparent decline after 65 years of age was mostly explained.

Discussion: These data suggest that, in white men, weight increases steadily until age 65 and then plateaus. These findings emphasize the necessity of longitudinal rather than cross‐sectional data to describe lifetime weight patterns.