bluuebunny/crossref_metadata_2025 huggingface dataset:
Blinking Mechanism of Colloidal Semiconductor Quantum Dots: Role of Fluctuating Double Layer Potential
Authors: Dutta Mitra , Stroscio Michael A. , Liao Sicheng , Vasudev Milana , Yamanaka Takayuki
Published: April 2007

Colloidal semiconductor quantum dots are observed to blink with off- and on-times, τoff, and τon, respectively, that obey inverse power law distributions. In this paper, the role of the fluctuating double-layer potential in the blinking phenomenon is examined. As discussed, the existence of an energy barrier, E, that is a stochastic variable with an exponential distribution pE(E) = (1/Eo)exp(-E/Eo) in terms of the height of the energy variable, results in a distribution in the thermal activation time τ, pτ(τ), is described by an inverse power law. As discussed, in such cases, an Arrhenius process is characterized by a thermal activation time, τ, where τ = τoexp(E/kBT) and E represents the energy barrier, T is the temperature, kB is Boltzmann's constant, and τo is a typical time. These principles are applied to the case of colloidal semiconductor quantum dots in electrolytic suspensions to analyze the role of the fluctuating double- layer potential in the blinking of colloidal semiconductor quantum dots.
Challenging the Electrodeposition of Multinary Semiconductor Compounds: Case of CuInSe2
Authors: Chassaing Elisabeth , Roussel Olivier G. , Ramdani Omar , Grand Pierre-Philippe , Canava Bruno , Etcheberry A. , Guillemoles Jean-Francois , Lincot Daniel
Published: April 2007

The electrodeposition of multinary compounds is of key importance for future technologies. Cu-In-Se system represents a case example, with a great potential in the field of photovoltaics. At IRDEP we achieved efficiencies up to 11.5% based on electrodeposited Cu-In-Se material. In the present paper, nucleation and growth steps of CuInSe2 are studied by polarization, impedance spectroscopy and SEM. The bulk composition is measured by x-ray fluorescence. The chemical environment of Cu, Se and In and the surface composition are analysed by XPS. A quasi-instantaneous 3D nucleation is observed. Binary Cu-Se nuclei are first obtained, which induce the incorporation of indium leading to CuInSe2. With increasing growth, secondary phases and Se(0) are obtained. At the threshold of potential corresponding to indium incorporation, a blocking adsorbate is formed, which is reduced at higher cathodic overvoltage into Cu-In-Se compound. These results are discussed in terms of general behavior of multinary compound deposition.
FFT Impedance Spectroscopy Analysis of the Growth of Anodic Oxides on Si with Various Electrolytes
Authors: Leisner Malte , Carstensen Juergen , Foell Helmut
Published: April 2007

The growth of anodic oxides on (100) p-Si has been analyzed with FFT impedance spectroscopy (FFTIS) in a comparative study for several organic electrolytes , as well as H2O. Measurement results strongly support the model of anodic oxide growth contained in the Current-Burst-Model (CBM), developed earlier in the context of current / voltage oscillations. Based on this model the mechanisms of the anodic oxidation were studied in detail not only qualitatively, but also quantitatively. FFTIS allows, e.g., the in-situ monitoring of the oxide layer thickness or the oxide coverage. The analyzed oxides could be grouped into essentially two different classes according to their structure as measured by atomic force microscopy, in good agreement with predictions from the FFTIS results.
Photo-Induced Stick-Slip on Super-Hydrophilic Semiconductor Surfaces
Authors: Denison Kieth R. , Boxall Colin
Published: April 2007

The time and relative humidity dependencies of photo-induced super-hydrophilicity on m-TiO2 films have been evaluated through the spreading of a sessile water drop on a UV- illuminated surface. Results obtained at 100% RH show that drops on m-TiO2 exhibit a photo-induced stick-slip behavior, the first time such an effect has been observed. The potential energy barrier U due to the surface inhomogeneities that oppose the onset of movement of the triple line has been obtained as a function of illumination time, also for the first time. U is found to decrease with time, a phenomenon attributed to the influence of the photo-generation of Ti-OH groups on those inhomogeneities affected by surface hydrophilicity.
Evaluation of Etch Behavior of Doped Silicon in Wet Cleaning of Silicon Wafer
Authors: Sinha Drew
Published: April 2007

Recent increases in the demand for advanced discrete and power devices produced from low-resistivity heavily-doped wafer demand better understanding of the surface preparation for this type of silicon wafer. Production of these doped wafers with low surface defects require, among other things, etch behavior of the materials by the standard clean (SC1) solution of the wet cleaning process. Determination of the silicon etch rate of a number of N-type and P-type doped epitaxial silicon wafers with different crystal orientations, dopant types and dopant levels have been made. Furthermore, observed variation in the removal rate of the chemical mechanical polishing (CMP) process for these doped silicon wafers is correlated with the etch rates. The surface quality of these wafers following CMP and SC1 chemical treatment is found to impact the defect level and cleanliness of the post-CMP cleaning process. Information obtained thereof is useful to develop wafer manufacturing process starting from silicon crystal to the final clean substrate or epi wafer with low surface defect.
Progesterone reduces the migration of mast cells toward the chemokine stromal cell-derived factor-1/CXCL12 with an accompanying decrease in CXCR4 receptors
Authors: Belot Marie-Pierre , Abdennebi-Najar Latifa , Gaudin Françoise , Lieberherr Michèle , Godot Véronique , Taïeb Joelle , Emilie Dominique , Machelon Véronique
Published: April 2007

Mast cell recruitment is implicated in many physiological functions and several diseases. It depends on microenvironmental factors, including hormones. We have investigated the effect of progesterone on the migration of HMC-1560mast cells toward CXCL12, a chemokine that controls the migration of mast cells into tissues. HMC-1560mast cells were incubated with 1 nM to 1 μM progesterone for 24 h. Controls were run without progesterone. Cell migration toward CXCL12 was monitored with an in vitro assay, and statistical analysis of repeated experiments revealed that progesterone significantly reduced cell migration without increasing the number of apoptotic cells ( P = 0.0084, n = 7). Differences between progesterone-treated and untreated cells were significant at 1 μM ( P < 0.01, n = 7). Cells incubated with 1 μM progesterone showed no rearrangment of actin filaments in response to CXCL12. Progesterone also reduced the calcium response to CXCL12 and Akt phosphorylation. Cells incubated with progesterone had one-half the control concentrations of CXCR4 (mRNA, total protein, and membrane-bound protein). Progesterone also inhibited the migration of HMC-1560cells transfected with hPR-B-pSG5 plasmid, which contained 2.5 times as much PR-B as the control. These transfected cells responded differently ( P < 0.05, n = 5) from untreated cells to 1 nM progesterone. We conclude that progesterone reduces mast cell migration toward CXCL12 and that CXCR4 may be a progesterone target in mast cells.
PPAR-γ knockout in pancreatic epithelial cells abolishes the inhibitory effect of rosiglitazone on caerulein-induced acute pancreatitis
Authors: Ivashchenko C. Y. , Duan S. Z. , Usher M. G. , Mortensen R. M.
Published: April 2007

Peroxisome proliferator-activated receptor-γ (PPAR-γ) agonists, such as the thiazolidinediones (TZDs), decrease acute inflammation in both pancreatic cell lines and mouse models of acute pancreatitis. Since PPAR-γ agonists have been shown to exert some of their actions independent of PPAR-γ, the role of PPAR-γ in pancreatic inflammation has not been directly tested. Furthermore, the differential role of PPAR-γ in endodermal derivatives (acini, ductal cells, and islets) as opposed to the endothelial or inflammatory cells is unknown. To determine whether the effects of a TZD, rosiglitazone, on caerulein-induced acute pancreatitis are dependent on PPAR-γ in the endodermal derivatives, we created a cell-type specific knock out of PPAR-γ in pancreatic acini, ducts, and islets. PPAR-γ knockout animals show a greater response in some inflammatory genes after caerulein challenge. The anti-inflammatory effect of rosiglitazone on edema, macrophage infiltration, and expression of the proinflammatory cytokines is significantly decreased in pancreata of the knockout animals compared with control animals. However, rosiglitazone retains its effect in the lungs of the pancreatic-specific PPAR-γ knockout animals, likely due to direct anti-inflammatory effect on lung parenchyma. These data show that the PPAR-γ in the pancreatic epithelia and islets is important in suppressing inflammation and is required for the anti-inflammatory effects of TZDs in acute pancreatitis.
The homeodomain transcription factors Cdx1 and Cdx2 induce E-cadherin adhesion activity by reducing β- and p120-catenin tyrosine phosphorylation
Authors: Ezaki Toshihiko , Guo Rong-Jun , Li Hong , Reynolds Albert B. , Lynch John P.
Published: April 2007

The homeodomain transcription factors Cdx1 and Cdx2 are regulators of intestine-specific gene expression. They also regulate intestinal cell differentiation and proliferation; however, these effects are poorly understood. Previously, we have shown that expression of Cdx1 or Cdx2 in human Colo 205 cells induces a mature colonocyte morphology characterized by the induction of a polarized, columnar shape with apical microvilli and strong cell-cell adhesion. To elucidate the mechanism underlying this phenomenon, we investigated the adherens junction complex. Cdx1 or Cdx2 expression reduced Colo 205 cell migration and invasion in vitro, suggesting a physiologically significant change in cadherin function. However, Cdx expression did not significantly effect E-cadherin, α-, β-, or γ-catenin, or p120-catenin protein levels. Additionally, no alteration in their intracellular distribution was observed. Cdx expression did not alter the coprecipitation of β-catenin with E-cadherin; however, it did reduce p120-catenin-E-cadherin coprecipitation. Tyrosine phosphorylation of β- and p120-catenin is known to disrupt E-cadherin-mediated cell adhesion and is associated with robust p120-catenin/E-cadherin interactions. We specifically investigated β- and p120-catenin for tyrosine phosphorylation and found that it was significantly diminished by Cdx1 or Cdx2 expression. We restored β- and p120-catenin tyrosine phosphorylation in Cdx2-expressing cells by knocking down the expression of protein tyrosine phosphatase 1B and noted a significant decline in cell-cell adhesion. We conclude that Cdx expression in Colo 205 cells induces E-cadherin-dependent cell-cell adhesion by reducing β- and p120-catenin tyrosine phosphorylation. Ascertaining the mechanism for this novel Cdx effect may improve our understanding of the regulation of cell-cell adhesion in the colonic epithelium.
Contributions of endothelium-derived relaxing factors to control of hindlimb blood flow in the mouse in vivo
Authors: Fitzgerald Sharyn M. , Bashari Homaira , Cox Jessica A. , Parkington Helena C. , Evans Roger G.
Published: April 2007

We determined the contributions of various endothelium-derived relaxing factors to control of basal vascular tone and endothelium-dependent vasodilation in the mouse hindlimb in vivo. Under anesthesia, catheters were placed in a carotid artery, jugular vein, and femoral artery (for local hindlimb circulation injections). Hindlimb blood flow (HBF) was measured by transit-time ultrasound flowmetry. Nω-nitro-l-arginine methyl ester (l-NAME, 50 mg/kg plus 10 mg·kg−1·h−1), to block nitric oxide (NO) production, altered basal hemodynamics, increasing mean arterial pressure (30 ± 3%) and reducing HBF (−30 ± 12%). Basal hemodynamics were not significantly altered by indomethacin (10 mg·kg−1·h−1), charybdotoxin (ChTx, 3 × 10−8 mol/l), apamin (2.5 × 10−7 mol/l), or ChTx plus apamin (to block endothelium-derived hyperpolarizing factor; EDHF). Hyperemic responses to local injection of acetylcholine (2.4 μg/kg) were reproducible in vehicle-treated mice and were not significantly attenuated by l-NAME alone, indomethacin alone, l-NAME plus indomethacin with or without co-infusion of diethlyamine NONOate to restore resting NO levels, ChTx alone, or apamin alone. Hyperemic responses evoked by acetylcholine were reduced by 29 ± 11% after combined treatment with apamin plus charybdotoxin, and the remainder was virtually abolished by additional treatment with l-NAME but not indomethacin. None of the treatments altered the hyperemic response to sodium nitroprusside (5 μg/kg). We conclude that endothelium-dependent vasodilation in the mouse hindlimb in vivo is mediated by both NO and EDHF. EDHF can fully compensate for the loss of NO, but this cannot be explained by tonic inhibition of EDHF by NO. Control of basal vasodilator tone in the mouse hindlimb is dominated by NO.
Use of consomic rats for genomic insights into ventilator-associated lung injury
Authors: Nonas Stephanie A. , Vinasco Liliana Moreno , Ma Shwu Fan , Jacobson Jeffrey R. , Desai Ankit A. , Dudek Steven M. , Flores Carlos , Hassoun Paul M. , Sam Lee , Ye Shui Q. , Moitra Jaideep , Barnard Joe , Grigoryev Dmitry N. , Lussier Yves A. , Garcia Joe G. N.
Published: April 2007

Increasing evidence supports the contribution of genetic influences on susceptibility/severity in acute lung injury (ALI), a devastating syndrome requiring mechanical ventilation with subsequent risk for ventilator-associated lung injury (VALI). To identify VALI candidate genes, we determined that Brown Norway (BN) and Dahl salt-sensitive (SS) rat strains were differentially sensitive to VALI (tidal volume of 20 ml/kg, 85 breaths/min, 2 h) defined by bronchoalveolar lavage (BAL) protein and leukocytes. We next exploited differential sensitivities and phenotyped both the VALI-sensitive BN and the VALI-resistant SS rat strains by expression profiling coupled to a bioinformatic-intense candidate gene approach (Significance Analysis of Microarrays, i.e., SAM). We identified 106 differentially expressed VALI genes representing gene ontologies such as “transcription” and “chemotaxis/cell motility.” We mapped the chromosomal location of the differentially expressed probe sets and selected consomic SS rats with single BN introgressions of chromosomes 2, 13, and 16 (based on the highest density of probe sets) while also choosing chromosome 20 (low probe sets density). VALI exposure of consomic rats with introgressions of BN chromosomes 13 and 16 resulted in significant increases in both BAL cells and protein (compared to parental SS strain), whereas introgression of BN chromosome 2 displayed a large increase only in BAL protein. Introgression of BN chromosome 20 had a minimal effect. These results suggest that genes residing on BN chromosomes 2, 13, and 16 confer increased sensitivity to high tidal volume ventilation. We speculate that the consomic-microarray-SAM approach is a time- and resource-efficient tool for the genetic dissection of complex diseases including VALI.
The influence of anti-inflammatory medication on exercise-induced myogenic precursor cell responses in humans
Authors: Mackey Abigail L. , Kjaer Michael , Dandanell Sune , Mikkelsen Kristian H. , Holm Lars , Døssing Simon , Kadi Fawzi , Koskinen Satu O. , Jensen Charlotte H. , Schrøder Henrik D. , Langberg Henning
Published: April 2007

The consumption of nonsteroidal anti-inflammatory drugs (NSAIDs) is widespread among athletes when faced with muscle soreness or injury, but the effects of NSAIDs on satellite cell activity in humans are unknown. To investigate this, 14 healthy male endurance athletes (mean peak oxygen consumption 62 ml·kg−1·min−1) volunteered for the study, which involved running 36 km. They were divided into two groups and received either 100 mg indomethacin per day or placebo. Muscle biopsies collected before the run and on days 1, 3, and 8 afterward were analyzed for satellite cells by immunohistochemistry with the aid of neural cell adhesion molecule (NCAM) and fetal antigen-1 (FA1) antibodies. Muscle biopsies were also collected from untrained individuals for comparison. Compared with preexercise levels, a 27% increase in the number of NCAM+ cells was observed on day 8 postexercise in the placebo group ( P < 0.05), while levels remained similar at all time points in the NSAID group. No change was seen in the proportion of FA1+ cells, although lower levels were found in the muscle of endurance-trained athletes compared with untrained individuals ( P < 0.05). These results suggest that ingestion of anti-inflammatory drugs attenuates the exercise-induced increase in satellite cell number, supporting the role of the cyclooxygenase pathway in satellite cell activity.
Hemodynamic consequences of rapid changes in posture in humans
Authors: Sheriff Don D. , Nådland Inger-Helene , Toska Karin
Published: April 2007

Tolerance to +G z gravitational stress is reduced when +G z stress is preceded by exposure to hypogravity (fraction, 0, or negative G z). For example, there is an exaggerated fall in eye-level arterial pressure (ELAP) early on during +G z stress (head-up tilt; HUT) when this stress is immediately preceded by −G z stress (head-down tilt; HDT). The aims of the present study were to characterize the hemodynamic consequences of brief HDT on subsequent HUT and to test the hypothesis that an elevation in leg vascular conductance induced by −G z stress contributes to the exaggerated fall in ELAP. Young healthy subjects ( n = 3 men and 4 women) were subjected to 30 s of 30° HUT from a horizontal position and to 30 s of 30° HUT when HUT was immediately preceded by 20 s of −15° HDT. Four bouts of HDT-HUT were alternated between five bouts of HUT in a counterbalanced designed to minimize possible time effects of repeated exposure to gravitational stress. One minute was allowed for recovery between tilts. Brief exposure to HDT elicited an exaggerated fall in ELAP during the first seconds of the subsequent HUT (−17.9 ± 1.4 mmHg) compared with HUT alone (−12.4 ± 1.2 mmHg, P <0.05) despite a greater rise in stroke volume (Doppler ultrasound) and cardiac output over this brief time period in the HDT-HUT trials compared with the HUT trials (thereafter stroke volume fell under both conditions). The greater fall in ELAP was associated with an exaggerated increase in leg blood flow (femoral artery Doppler ultrasound) and was therefore largely (70%) attributable to an exaggerated rise in estimated leg vascular conductance, confirming our hypotheses. Thus brief exposure to −G z stress leads to an exaggerated fall in ELAP during subsequent HUT, owing to an exaggerated increase in estimated leg vascular conductance.
The Anorexia of Aging
Authors: Di Francesco Vincenzo , Fantin Francesco , Omizzolo Francesca , Residori Luigi , Bissoli Luisa , Bosello Ottavio , Zamboni Mauro
Published: April 2007

Malnutrition in the elderly is one of the greatest threats to health, well-being and autonomy, it is therefore crucial to understand and to contrast the causal factors of inadequate energy intake. This review focuses on the mechanisms of the so-called ‘anorexia of aging’. In recent years, it has been shown that elderly subjects have abnormal peripheral signal patterns and alterations in central hypothalamic control relays. Negative feedback from impaired gastric motility, exaggerated long-term adiposity signals (leptin, insulin) and postprandial anorexigenic signals (CCK, PYY) seem to prevail over the central feeding drive. If nutritional strategies of intervention are to be improved, these data need to be taken into account.
Bowel Care in the Elderly
Authors: Spinzi G.C.
Published: April 2007

Background: Intestinal complaints are a frequent health concern for elderly people and their care providers. Aims: To explore the distinction between constipation and the subjective complaints in elderly people and to review the diagnosis, causes and treatment of constipation, fecal impaction, and fecal incontinence. Methods: Review of studies that give information on prevalence, causes, symptoms, and treatment of bowel problems in the elderly, excluding uncontrolled clinical observations. Results: Self-reported constipation and laxative use increase with age and are more common among women, blacks and people of low socio-economic level. The patient’s pharmacological history is fundamental, because medications are the cause of up to 40% of chronic constipation, and are often used inappropriately. The results of most laxative trials require cautious interpretation, but fiber and laxatives are more effective than placebo against constipation. Much additional research is needed to determine the most cost-effective method of treating intestinal complaints in the elderly. Conclusions: Bowel problems in older people have a considerable impact on the quality of life and have many contributory causes that are often amenable to treatment and management. Results of therapy can be good, leading to alleviation of suffering and the ability to lead a fuller life.
Minimally Differentiated Acute Myeloid Leukemia with t(12;22)(p13;q11) Translocation Showing Primary Multidrug Resistance and Expressing Multiple Multidrug-Resistant Proteins
Authors: Chen Suning , Xue Yongquan , Zhu Xinghu , Wu Yafang , Pan Jinlan
Published: April 2007

Here we report a rare chromosomal translocation, t(12;22)(p13;q11), which was detected in a 53-year-old female patient diagnosed as having minimally differentiated acute myeloid leukemia (AML-M0) according to the French-American-British classification criteria. Chromosome painting analysis with probes for chromosomes 12 and 22 confirmed the result of the conventional cytogenetic analysis. Reverse transcriptase polymerase chain reaction revealed the TEL-MN1 fusion transcript. Interestingly, she presented primary multidrug resistance and did not respond to several kinds of chemotherapy regimens. Moreover, she could not achieve remission after two doses of monotherapy with Mylotarg. Flow cytometry analysis detected high levels of expression of P-glycoprotein, multidrug-resistant-related protein, lung-related protein, and glutathione S-transferase π in this case at presentation. As far as we know, this is the first report of t(12;22)(p13;q11) translocation involving TEL and MN1 genes in an AML-M0 patient.
Extranodal Natural Killer/T-Cell Lymphoma, Nasal Type, in a Patient with a Constitutional 11q Terminal Deletion Disorder
Authors: Gaitonde Sujata , Attele Anoja , Abutalib Syed A. , Rondelli Damiano , Lindgren Valerie
Published: April 2007

Background: Most cases of constitutional 11q terminal deletion disorder are children. Malignancy is a potential concern, as these children reach adulthood. However, since the majority of patients are young, their risk of developing malignancy in adulthood is essentially unknown. Aim: To report the first hematologic malignancy [extranodal natural killer (NK)/T-cell lymphoma, nasal type] arising in the trachea of a patient with constitutional 11q terminal deletion disorder. Our patient is the oldest patient reported in the literature. It is of note that this cytogenetic abnormality has not been described as a recurring abnormality in extranodal NK/T-cell lymphoma. Case Report: A 36-year-old male with congenital psychomotor retardation was transferred to our hospital. Pathologic evaluation was diagnostic of extranodal NK/T-cell lymphoma, nasal type. Staging marrow was negative for lymphoma, but cytogenetic analysis revealed a constitutional deletion of chromosome 11 at band q23 [46,XY,del(11)(q23)(c)]. This abnormality was present in a subsequent bone marrow specimen, along with an acquired abnormality, namely an extra copy of part of the long arm of chromosome 1 translocated to the short arm of chromosome 14. Conclusion: Patients with 11q terminal deletion disorder who reach adulthood may be predisposed to develop neoplasias by virtue of the constitutional deletion.
Size Matters
Authors: Christoforidis Gregory A. , Slivka Andrew , Mohammad Yousef , Karakasis Christopher , Avutu Bindu , Yang Ming
Published: April 2007

Background and Purpose—

This study defines significant thrombolysis associated intracranial hemorrhage (ICH) by identifying an objective threshold volume that predicts clinical deterioration attributable to ICH.

Methods—

Prospectively collected clinical and radiographic information, from 103 consecutive patients who underwent intraarterial thrombolysis for acute ischemic stroke, was reviewed. Multiple paired comparisons between stratified hematoma volume and change in National Institutes of Health Stroke Scale (NIHSS) score by 24 to 36 hours and by time of hospital discharge was used to identify significant differences. Associations between hemorrhage volume and infarct volume in relation to clinical outcomes were examined. Rates of hemorrhagic transformation (HT), symptomatic hemorrhage, and parenchymal hematoma involving over 30% of the infarct were compared with hemorrhage volume. Multivariate regression analysis was used to determine the relationship between change in discharge NIHSS score and hemorrhage volume adjusting for known predictors of clinical outcomes.

Results—

Multiple paired comparisons indicate that hemorrhage greater than 25 mL (HV25) had a more distinct impact on NIHSS score by time of hospital discharge than at 24 to 36 hours. Twenty-seven (26.2%) patients had HT and 12 (11.7%) had HV25. Among symptomatic hemorrhage, parenchymal hematoma involving over 30% of the infarct, and HV25, HV25 appeared more reflective of clinical deterioration from ICH. Hemorrhage volume increased with infarct volume but they were independently associated with change in NIHSS score on regression analysis.

Conclusion—

Clinical deterioration from ICH and ischemic injury are more effectively distinguished at time of hospital discharge. The authors propose to define significant hemorrhage associated with thrombolysis as hemorrhage volume greater than 25 mL.
New Pediatric Model of Ischemic Stroke in Infant Piglets by Photothrombosis
Authors: Kuluz John W. , Prado Ricardo , He Dansha , Zhao Weizhao , Dietrich W. Dalton , Watson Brant
Published: April 2007

Background and Purpose—

The etiology and pathophysiology of acute ischemic stroke in children differ greatly from those in adults. The purpose of this study was to establish a new pediatric model of ischemic stroke in infant piglets for use in future studies of the response of the developing brain to focal ischemic injury.

Methods—

Ischemic stroke was produced in male infant piglets (2 to 4 weeks old) by photothrombotic occlusion of the middle cerebral artery. Regional cerebral blood flow was measured with radiolabeled microspheres up to 4 hours after occlusion. Early histopathology, including caspase-3 immunohistochemistry for apoptosis, was examined 4 hours after ischemia. The nature of the thrombus and its interaction with vascular endothelium were assessed by electron microscopy.

Results—

Severe ischemia (0 to 15 mL/100 g per min) occurred rapidly in 1.4±0.2 g of tissue at 15 minutes and increased to 2.4±0.7 g at 4 hours. Similarly, moderate ischemia (16 to 30 mL/100 g per min) was measured in 1.2±0.3 g of tissue at 15 minutes and increased to 2.0±0.6 g at 4 hours. These regional cerebral blood flow values represent ischemic levels of blood flow in 20% to 25% of the volume of the ischemic hemisphere at 4 hours after ischemia. Ischemic infarction occurred in both gray and white matter, and cerebral microvessels in the ischemic hemisphere contained large numbers of inflammatory leukocytes. Caspase-3–positive cells were few in number and were found in the periphery of the infarct; cell death appeared to occur primarily by necrosis rather than apoptosis at 4 hours. Electron microscopy revealed a pure platelet thrombus firmly attached to the vascular endothelium, which in some areas appeared to be detached from the basement membrane.

Conclusions—

Ischemic stroke can be produced in infant piglets by middle cerebral artery photothrombosis. The stroke involved both gray and white matter and exhibited a robust inflammatory component. The mean infarct volume determined histopathologically amounted to 9.6±2.4% of the affected (ipsilateral) hemisphere, which was correlated well with the mass equivalent of tissue (12.0±3.5%), in which severe declines in regional cerebral blood flow were observed at 4 hours.
Has Free Radical Release Across the Brain After Carotid Endarterectomy Traditionally Been Underestimated?
Authors: Bailey Damian M. , Morris-Stiff Gareth , McCord Joe M. , Lewis Michael H.
Published: April 2007

Background and Purpose—

Ischemia-reperfusion is an established paradigm for the induction of neuro-oxidative stress. The present report highlights the limitations associated with the measurement of free radical exchange across the human brain after carotid endarterectomy if reperfusion hemodynamics are not taken into account.

Summary of Report—

Only 2 human studies have reported local changes in the arterio-jugular bulb venous concentration difference (

a-v
diff

) of free radicals during carotid endarterectomy. The authors reported either no change or only a very minor trans-cerebral release during the course of reperfusion, which was unexpected. However, consistent with other surgical models of ischemia-reperfusion, reperfusion would have been expected to increase plasma volume consistent with reflow-hemodilution. This would artifactually dilute the local concentration of free radicals, attenuate the

a-v
diff

and thus underestimate the “true” magnitude of cerebral free radical release.

Conclusion—

After correction for reflow-hemodilution, the cerebral generation of free radicals after carotid endarterectomy is likely to be significantly more pronounced than previously documented in humans.
Power M-Mode Doppler and Single-Gate Spectral Analysis Using a 2-MHz Pulsed-Wave Doppler Transducer to Directly Detect Cervical Internal Carotid Artery Stenosis
Authors: Popa Vasile N. , Spencer Merrill P. , Lion Charlene L. , Felberg Robert A.
Published: April 2007

Background and Purpose—

We hypothesized that direct cervical investigation with Power M-Mode Doppler (PMD) combined with single-gate Doppler spectral analysis (SGDSA) using a 2-MHz pulsed-wave Doppler transducer would show reasonable accuracy parameters when compared with standard color-coded carotid duplex ultrasound (CDU).

Methods—

We prospectively screened for cervical internal carotid artery (ICA) stenosis by direct observation using a 2 MHz PMD/SGDSA device. PMD identified the artery (location, depth, flow direction) and SGDSA assessed waveform; peak systolic, end diastolic, and mean flow velocities (MFV) of the common carotid artery; cervical ICA proximally and distally; and external carotid artery. Diagnostic accuracy was compared with concurrent carotid duplex ultrasound. The continuity principle was applied using the proximal/distal cervical ICA MFV ratio.

Results—

We examined 456 vessels (228 patients). Using ICA proximally/ICA distally MFV ratio of 1.5 or greater or absence of ICA signature, for 40% to 59% or greater stenosis (including occlusions), sensitivity was 75.4%, specificity 99.8%, positive predictive value 97.7%, negative predictive value 96.6%, and accuracy 96.7%. For MFV ratio 1.6 or greater or absence of ICA signature and 60% to 79% or greater stenosis (including occlusions), sensitivity was 92.3%, specificity 98.1%, positive predictive value 81.8%, negative predictive value 99.3%, and accuracy 97.6%.

Conclusions—

Use of combined PMD and SGDSA to directly observe the extracranial ICA is reasonably accurate compared with carotid duplex ultrasound. Using the MFV ratio of proximal/distal extracranial ICA improves accuracy parameters and provides a quick and effective bedside screen for ICA stenosis. This novel technique should be considered part of the standard PMD/transcranial Doppler examination.
Bulk Scattering Properties for the Remote Sensing of Ice Clouds. Part III: High-Resolution Spectral Models from 100 to 3250 cm−1
Authors: Baum Bryan A. , Yang Ping , Nasiri Shaima , Heidinger Andrew K. , Heymsfield Andrew , Li Jun
Published: April 2007

This study reports on the development of bulk single-scattering models for ice clouds that are appropriate for use in hyperspectral radiative transfer cloud modeling over the spectral range from 100 to 3250 cm−1. The models are developed in a manner similar to that recently reported for the Moderate-Resolution Imaging Spectroradiometer (MODIS); therefore these models result in a consistent set of scattering properties from visible to far-infrared wavelengths. The models incorporate a new database of individual ice-particle scattering properties that includes droxtals, 3D bullet rosettes, hexagonal solid and hollow columns, aggregates, and plates. The database provides single-scattering properties for each habit in 45 size bins ranging from 2 to 9500 μm, and for 49 wavenumbers between 100 and 3250 cm−1, which is further interpolated to 3151 discrete wavenumbers on the basis of a third-order spline interpolation method. Bulk models are developed by integrating various properties over both particle habit and size distributions. Individual bulk models are developed for 18 effective diameters Deff, ranging from Deff = 10 μm to Deff = 180 μm. A total of 1117 particle size distributions are used in the analyses and are taken from analysis of the First International Satellite Cloud Climatology Project Regional Experiment (FIRE)-I, FIRE-II, Atmospheric Radiation Measurement Program intensive operation period (ARM-IOP), Tropical Rainfall Measuring Mission Kwajalein Experiment (TRMM-KWAJEX), and Cirrus Regional Study of Tropical Anvils and Cirrus Layers Florida-Area Cirrus Experiment (CRYSTAL-FACE) data. The models include microphysical and scattering properties such as median mass diameter, effective diameter, single-scattering albedo, asymmetry factor, and scattering phase function. The spectral models are appropriate for applications involving the interpretation of the radiometric measurements of ice clouds acquired by infrared spectrometers such as the Atmospheric Infrared Sounder (AIRS) on the NASA Aqua satellite and the Cross-Track Infrared Sounder (CrIS) on the upcoming National Polar-Orbiting Environmental Satellite System (NPOESS) platforms.
Urban Modification in a Mesoscale Model and the Effects on the Local Circulation in the Pearl River Delta Region
Authors: Lo Jeff C. F. , Lau Alexis K. H. , Chen Fei , Fung Jimmy C. H. , Leung Kenneth K. M.
Published: April 2007

The Pearl River Delta (PRD) region, located in the southern part of Guangdong Province in China, is one of the most rapidly developing regions in the world. The evolution of local and regional sea-breeze circulation (SBC) is believed to be responsible for forming meteorological conditions for high air-pollution episodes in the PRD. To understand better the impacts of urbanization and its associated urban heat island (UHI) on the local- and regional-scale atmospheric circulations over PRD, a number of high-resolution numerical experiments, with different approaches to treat the land surface and urban processes, have been conducted using the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5). The results show that an accurate urban land-use dataset and a proper urban land-use parameterization are critical for the mesoscale model to capture the major features of the observed UHI effect and land–sea-breeze circulations in the PRD. Stronger UHI in the PRD increases the differential temperature gradient between urbanized areas and nearby ocean surface and hence enhances the mesoscale SBC. The SBC front consequently penetrates farther inland to overcome the prevailing easterly flow in the western part of inland Hong Kong. Additional sensitivity studies indicate that further industrial development and urbanization will strengthen the daytime SBC as well as increase the air temperature in the lowest 2 km of the atmosphere.
An Empirical Orthogonal Function Iteration Approach for Obtaining Homogeneous Radiative Fluxes from Satellite Observations
Authors: Zhang Banglin , Pinker Rachel T. , Stackhouse Paul W.
Published: April 2007

Conventional observations of climate parameters are sparse in space and/or time, and the representativeness of such information needs to be optimized. Observations from satellites provide improved spatial coverage over point observations; however, they pose new challenges for obtaining homogeneous coverage. Surface radiative fluxes, the forcing functions of the hydrologic cycle and biogeophysical processes, are now becoming available from global-scale satellite observations. They are derived from independent satellite platforms and sensors that differ in temporal and spatial resolution and in the size of the footprint from which information is derived. Data gaps, degraded spatial resolution near boundaries of geostationary satellites, and different viewing geometries in areas of satellite overlap could result in biased estimates of radiative fluxes. In this study will be discussed issues related to the sources of inhomogeneity in surface radiative fluxes as derived from satellites, development of an approach to obtain homogeneous datasets, and application of the method to the widely used International Satellite Cloud Climatology Project data that currently serve as a source of information for deriving estimates of surface and top-of-the-atmosphere radiative fluxes. Introduced is an empirical orthogonal function (EOF) iteration scheme for homogenizing the fluxes. The scheme is evaluated in several ways, including comparison of the inferred radiative fluxes with ground observations, both before and after the EOF approach is applied. On the average, the latter reduces the RMS error by about 2–3 W m−2.
Fine Structure of Vertical Motion in the Stratiform Precipitation Region Observed by a VHF Doppler Radar Installed in Sumatra, Indonesia
Authors: Nishi Noriyuki , Yamamoto Masayuki K. , Shimomai Toyoshi , Hamada Atsushi , Fukao Shoichiro
Published: April 2007

Vertical motion W profiles in the stratiform precipitation region of mesoscale cloud clusters were investigated using wind data observed by VHF Doppler radar installed in western Sumatra Island (0.2°S, 100.32°E). A special mode for W observations was introduced in November 2003, and W data with high accuracy were obtained during most of the period, with fine resolutions of 3 min in time and 150 m in vertical direction. The typical fine structure of W within the nimbostratus in the stratiform precipitation region was investigated by the case study of 6, 8, and 20 November 2003. In the later 2 or 3 h of the stratiform precipitation period, gentle upward motions with small time and height fluctuations were observed over a several-kilometer height range from the middle to upper troposphere. Values of W were weakly positive (0–40 cm s−1) continuously, with little strong upward motion greater than 40 cm s−1 and downward motion.
Spain: A Success Story Shadowed Only by a Poor Productivity Performance
Authors: Mas Matilde , Quesada Javier
Published: April 2007

Since joining the European Union in 1986, the performance of the Spanish economy has been quite remarkable, acting as a good example for new entrants of what can be accomplished in twenty years. Its ability to generate employment has been astonishing. Departing from an environment of very high unemployment (close to 25 per cent), Spain has become the country of destination most preferred by immigrants. However, it has also had a scant productivity performance. The main burden on productivity growth lies with the construction sector and almost all private service sectors with the unique exception of the financial sector. Most likely, over the next years, the continuity of the Spanish success will require a reversal of the sources of growth, shifting from labour creation to improvements in multifactor productivity.
A New Approach to Measuring Health System Output and Productivity
Authors: Castelli Adriana , Dawson Diane , Gravelle Hugh , Jacobs Rowena , Kind Paul , Loveridge Pete , Martin Stephen , O'Mahony Mary , Stevens Philip Andrew , Stokes Lucy , Street Andrew , Weale Martin
Published: April 2007

This paper considers methods to measure output and productivity in the delivery of health services, with an application to NHS hospital sector. It first develops a theoretical framework for measuring quality adjusted outputs and then considers how this might be implemented given available data. Measures of input use are discussed and productivity growth estimates are presented for the period 1998/9-2003/4. The paper concludes that available data are unlikely fully to capture quality improvements.
Beyond the Silver Screen
Authors: David Ann R.
Published: April 2007

This article first highlights the relative paucity of literature on South Asian dance and provides a brief overview of existing material. It then examines particularly the influence of filmi or Bollywood dance on South Asian dance practices in the UK. It locates film dance within the Bollywood genre, noting its recent acceptance as a new form of popular culture and its attractions for the younger generation of British Asians. The place of dance in Hindi films is analysed and discussed briefly to con-textualise the relationship between such film dances and South Asian dance practices in Britain. Using evidence from fieldwork gathered in Leicester and London amongst dance teachers and students of South Asian dance, the article questions notions of identity, authenticity, tradition and the changing nature of dance transmission as Bollywood forms grow in popularity.
Who Shot the Mahatma? Representing Gandhian Politics in Indian Comic Books
Authors: McLain Karline
Published: April 2007

Amar Chitra Katha (‘Immortal Picture Stories’) is the leading Indian comic book series, with 440 mythological and historical titles and sales of over 86 million issues. In 1989, after twenty years of publishing success, the producers of this series decided to release two issues on the world-renowned Indian politician and activist, Mahatma Gandhi. But Gandhi, best known for his technique of non-violent civil resistance, presented a formidable challenge: How to depict the Mahatma, paragon of peace and non-violence, in a visual medium that is notorious for its action and violence? This article examines the relationship between text and image in these comics, and draws upon interviews with authors and artists, to better understand the contested memory of Gandhi in India today as well as the contested concept of non-violence.
Devolution of Financial Power to Local Self-Governments
Authors: Datta Polly
Published: April 2007

The article notes that though it was an early starter in decentralisation programmes, West Bengal seems to have failed to keep pace with the resurgence of Panchayati Raj Institutions (PRIs) in India during the 1990s and is now lagging behind other states. The Mukarji and Bandyopadhyay Committee found in their evaluation report in 1993 that the PRIs of West Bengal were suffer-ing from conceptual and programmatic constraints. Inability of the state to perceive the PRIs as self-government institutions was denoted as a conceptual constraint which, the Committee felt, eventually led to a programmatic constraint. The present study demonstrates that the conceptual limitation originally identified by the 1993 Committee appears to be legitimised in the very con-ceptualisation of the ‘feasibility frontier’ offered by the Left Front Government of West Bengal.
Predictive and Incremental Validity of Global and Domain-Based Adolescent Life Satisfaction Reports
Authors: Haranin Emily C. , Huebner E. Scott , Suldo Shannon M.
Published: April 2007

Concurrent, predictive, and incremental validity of global and domain-based adolescent life satisfaction reports are examined with respect to internalizing and externalizing behavior problems. The Students' Life Satisfaction Scale (SLSS), Multidimensional Students' Life Satisfaction Scale (MSLSS), and measures of internalizing and externalizing behavior problems from the Youth Self-Report of the Child Behavior Checklist are administered to secondary school students on three occasions, each separated by 1 year. As expected, concurrent and predictive validity correlations between the SLSS and MSLSS total scores and internalizing and externalizing behaviors are modest to moderate in magnitude, with correlations declining but remaining statistically significant across time. Results also reveal that the domain-based scores on the MSLSS (e.g., family, school) demonstrated incremental validity in relation to adolescents' global life satisfaction reports; that is, various domain-based scores contribute statistically significant variance above and beyond the variance associated with the global scores, depending on the criterion. Implications for assessments of life satisfaction among adolescents are discussed.
Making Sense of Multiple Informants in Child and Adolescent Psychopathology
Authors: Smith Steven R.
Published: April 2007

Behavior ratings and self-report measures of child and adolescent psychopathology are often used to explore the types and extent of psychological disorders in youth. Yet a review of the literature suggests that parent, teacher, and self-report of psychopathology are not generally highly correlated. Moreover, even among the same type of rater (e.g., parents), there is often very little concordance in ratings. Although there is a substantial literature related to the circumstances under which different informants can be expected to correlate, there is little to guide psychologists in clinical decision making. The present article briefly reviews issues related to both rater and child characteristics that affect the quality and utility of their ratings. The child characteristics of age, setting, and type of problem and the relationship of these to rating quality are highlighted. Last, suggestions are made about which rater should be given the most weight and when.
Technical Assistance
Authors: Miller John S. , Goswami Arkopal K.
Published: April 2007

Successful interagency cooperation regarding particular infrastructure investments, notably those involving transportation and land planning, is strikingly difficult to achieve. One successful approach entails the provision of technical assistance among agencies. This article reports the results of a 16-month pilot program where the local land development authority and the state department of transportation worked together to determine how land use affects transportation performance. The pilot confirmed published lessons for interagency cooperation but led to four new guidelines: (a) imperfectly and iteratively define a problem rather than waiting for all information, (b) get feedback early, (c) maintain momentum by setting short goals sufficiently tangible that they may be accomplished yet adequately difficult that they mark progress, and (d) change the project goal if the change will better suit the needs of the recipient of the assistance. Although simplistic, these guidelines reduce the common risk among busy agencies that nothing, rather than tangible assistance, will transpire.