bluuebunny/crossref_metadata_2025 huggingface dataset:
Interaction of water in polymers: Poly(ethylene‐co‐vinyl acetate) and poly(vinyl acetate)
Authors: Iwamoto Reikichi , Matsuda Toshihiko
Published: February 2005

We studied the interaction of water in poly(ethylene‐co‐vinyl acetate) of various vinyl acetate compositions and poly(vinyl acetate), on the basis of the infrared spectrum of the water dissolved therein. The spectrum shows a very sharp and distinct band at about 3690 cm−1 (named as A), and less‐sharp two bands around 3640 (B) and 3550 cm−1 (C), the A band being outstanding especially at a low vinyl acetate composition. As the vinyl acetate composition increases, the A band decreases in intensity relative to the C band, whereas the B band increases contrarily. Analysis of the spectral change has elucidated that one‐bonded water (of which one OH is hydrogen‐bonded to the CO of an ester group and the other OH is free) and two‐bonded water (each OH of which is hydrogen‐bonded to one CO) coexist in the copolymer and that two‐bonded water increases in relative population with increasing vinyl acetate composition. Dissolved water is entirely two‐bonded in poly(vinyl acetate), in which CO groups are densely distributed in the matrix. We proved that dissolved water in polymers is hydrogen‐bonded through one or two OH groups to the possessed functional groups but does not cluster. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 777–785, 2005
Semi-Automated Sample Preparation for Plasma Proteomics
Authors: Ho Keith , Xiao Qing , Fach Estelle M. , Hulmes Jeffrey D. , Bethea Deidra , Opiteck Gregory J. , Lu Joseph Y. , Kayne Paul S. , Hefta Stanley A.
Published: February 2005

The discovery of new biomarkers will be an essential step to enhance our ability to better diagnose and treat human disease. The proteomics research community has recently increased its use of human blood (plasma/serum) as a sample source for these discoveries. However, while blood is fairly non-invasive and readily available as a specimen, it is not easily analyzed by liquid chromatography (LC)/mass spectrometry (MS), because of its complexity. Therefore, sample preparation is a crucial step prior to the analysis of blood. This sample preparation must also be standardized in order to gain the most information from these valuable samples and to ensure reproducibility. We have designed a semi-automated and highly parallel procedure for the preparation of human plasma samples. Our process takes the samples through eight successive steps before analysis by LC/MS: (1) receipt, (2) reformatting, (3) filtration, (4) depletion, (5) concentration determination and normalization, (6) digestion, (7) extraction, and (8) randomization, triplication, and lyophilization. These steps utilize a number of different liquid handlers and liquid chromatography (LC) systems. This process enhances our ability to discover new biomarkers from human plasma.
GigaMatrix™: An Ultra High-Throughput Tool for Accessing Biodiversity
Authors: Lafferty Mike , Dycaico Mark J.
Published: February 2005

Recombinant approaches for tapping into the biodiversity present in nature for the discovery of novel enzymes and biosynthetic pathways can result in large gene libraries. Likewise, laboratory evolution techniques can result in large but potentially valuable libraries. Thorough screening of these libraries requires ultra high-throughput methods. The GigaMatrix™ screening platform addresses this opportunity using reusable high-density plates with 100,000 to 1,000,000 through-hole wells in a microplate footprint. In addition to throughputs of over 107 wells per day, the platform offers a significant reduction in reagent use and waste, has fully integrated automated “cherry picking,” and uses no complicated dispensing equipment. Wells containing putative hits from targeted fluorescent liquid phase assays are revealed by a fluorescent imaging system. Vision-guided robotics are utilized to recover hits by accessing individual 200 μm and smaller wells with a disposable sterile needle. The GigaMatrix platform has proven to be an effective and efficient tool for screening gene libraries for both discovery and evolution applications.
Conceptual Design for an Automated High-Throughput Magnetic Protein Complex Purification Workcell
Authors: Najmabadi Peyman , Goldenberg Andrew A. , Emili Andrew
Published: February 2005

One of the major challenges facing the emerging field of proteomics research is related to the technical difficulties in analyzing protein structure and function on a genomic scale. The routine purification of protein complexes as a means to investigate protein–protein interaction networks is of particularly high interest because of its significant potential to improve overall understanding of protein function and to improve ongoing drug discovery efforts. Automation of currently practiced laboratory procedures has the potential to markedly improve protein purification throughput, but important technical issues remain to be addressed. This paper investigates key bottlenecks in the automation of standard affinity-based procedures for protein complex purification and introduces a promising conceptual design for an automated workcell that would allow for rapid and efficient magnetic bead-based purification of protein complexes from model organisms suitable for a medium-sized research laboratory setting. The design specifications are based on a modular and flexible design that will permit routine, unattended batch isolation and processing of protein complexes from microbes.
Comparing academic and aboriginal definitions of Arctic identities
Authors: Dorais Louis-Jacques
Published: February 2005

During the last decades, scholarly studies on Arctic identities have been on the increase, but less is known about how academic viewpoints diverge from aboriginal perspectives. The aim of this article is to compare both points of view, by looking at the way some academic specialists define Arctic identities, in contrast — or convergence — with how one Arctic people, the Inuit, perceive who they are. Twelve scholars conducting social research in the north and recognised for their competence were interviewed on their definition of identity and their assessment of the current situation of Arctic aboriginal populations. Their responses show that they view identity as a relational and constructed process, a process that continues without much disruption despite rapid social and cultural change. As modern Inuit are concerned, ethnography and personal testimonies tend to show that they perceive identity as an open-ended and individual — as opposed to collective — relationship rather than as a way of classifying people. Inuit perceptions agree on some points — the relational aspects for instance — but diverge on others — for example, the primarily individual nature of identity — from those of the interviewed scholars, and they should be taken into account in any assessment of the current human situation in the Arctic.
Assessment of the global impact of aerosols on tropospheric oxidants
Authors: Tie Xuexi , Madronich Sasha , Walters Stacy , Edwards David P. , Ginoux Paul , Mahowald Natalie , Zhang RenYi , Lou Chao , Brasseur Guy
Published: February 2005

We present here a fully coupled global aerosol and chemistry model for the troposphere. The model is used to assess the interactions between aerosols and chemical oxidants in the troposphere, including (1) the conversion from gas‐phase oxidants into the condensed phase during the formation of aerosols, (2) the heterogeneous reactions occurring on the surface of aerosols, and (3) the effect of aerosols on ultraviolet radiation and photolysis rates. The present study uses the global three‐dimensional chemical/transport model, Model for Ozone and Related Chemical Tracers, version 2 (MOZART‐2), in which aerosols are coupled with the model. The model accounts for the presence of sulfate, soot, primary organic carbon, ammonium nitrate, secondary organic carbon, sea salt, and mineral dust particles. The simulated global distributions of the aerosols are analyzed and evaluated using satellite measurements (Moderate‐Resolution Imaging Spectroradiometer (MODIS)) and surface measurements. The results suggest that in northern continental regions the tropospheric aerosol loading is highest in Europe, North America, and east Asia. Sulfate, organic carbon, black carbon, and ammonium nitrate are major contributions for the high aerosol loading in these regions. Aerosol loading is also high in the Amazon and in Africa. In these areas the aerosols consist primarily of organic carbon and black carbon. Over the southern high‐latitude ocean (around 60°S), high concentrations of sea‐salt aerosol are predicted. The concentration of mineral dust is highest over the Sahara and, as a result of transport, spread out into adjacent regions. The model and MODIS show similar geographical distributions of aerosol particles. However, the model overestimates the sulfate and carbonaceous aerosol in the eastern United States, Europe, and east Asia. In the region where aerosol loading is high, aerosols have important impacts on tropospheric ozone and other oxidants. The model suggests that heterogeneous reactions of HO2 and CH2O on sulfate have an important impact on HOx (OH + HO2) concentrations, while the heterogeneous reaction of O3 on soot has a minor effect on O3 concentrations in the lower troposphere. The heterogeneous reactions on dust have very important impacts on HOx and O3 in the region of dust mobilization, where the reduction of HOx and O3 concentrations can reach a maximum of 30% and 20%, respectively, over the Sahara desert. Dust, organic carbon, black carbon, and sulfate aerosols have important impacts on photolysis rates. For example, the photodissociation frequencies of ozone and nitrogen dioxide are reduced by 20% at the surface in the Sahara, in the Amazon, and in eastern Asia, leading to 5–20% reduction in the concentration of HOx and to a few percent change in the O3 abundance in these regions.
Quantum integrability of the deformed elliptic Calogero–Moser problem
Authors: Khodarinova L. A.
Published: February 2005

The integrability of the deformed quantum elliptic Calogero–Moser problem introduced by Chalykh, Feigin, and Veselov is proven. Explicit recursive formulas for the integrals are found. For integer values of the parameter this implies the algebraic integrability of the systems.
Photodissociation of HI and DI: Polarization of atomic photofragments
Authors: Brown Alex
Published: February 2005

The complete angular momentum distributions and vector correlation coefficients (orientation and alignment) of ground state I(P3∕22) and excited state I(P1∕22) atoms resulting from the photodissociation of HI have been computed as a function of photolysis energy. The orientation and alignment parameters aQ(K)(p) that describe the coherent and incoherent contributions to the angular momentum distributions from the multiple electronic states accessed by parallel and perpendicular transitions are determined using a time-dependent wave packet treatment of the dissociation dynamics. The dynamics are based on potential energy curves and transition dipole moments that have been reported previously [R. J. LeRoy, G. T. Kraemer, and S. Manzhos, J. Chem. Phys. 117, 9353 (2002)] and used to successfully model the scalar (total cross section and branching fraction) and lowest order vector (anisotropy parameter β) properties of the photodissociation. Predictions of the aQ(K)(p), parameters for the isotopically substituted species DI are reported and contrasted to the analogous HI results. The resulting polarization for the corresponding H/D partners are also determined and demonstrate that both H and D atoms produced can be highly spin polarized. Comparison of these predictions for HI and DI with experimental measurement will provide the most stringent test of the current model for the electronic structure and the interpretation of the dissociation based on noncoupled excited state dynamics.
Transcellular induction of neuropeptide Y expression by NT4 and BDNF
Authors: Wirth Marcus J. , Patz Silke , Wahle Petra
Published: February 2005

The transcellular signaling of neurotrophins is postulated, but evidence is scarce. We now show that a small number of NT4- and BDNF-overexpressing neurons in the cortical explant of thalamocortical cocultures rapidly evoked a Trk receptor-dependent upregulation of neuropeptide Y (NPY) mRNA in interneurons. In contrast to BDNF, the action of NT4 was independent of calcium influx through NMDA receptors and L-type calcium channels. NPY neurons vastly outnumbered the neurotrophin-overexpressing neurons (mostly pyramidal cells), arguing for a spread of the neurotrophin signal via axonally connected neuronal populations. Furthermore, NT4 transfection of one explant of axonally connected corticocortical cocultures evoked significantly larger numbers of NPY neurons in both explants. Delivery of the signal was not by diffusion of neurotrophins via the medium. Moreover, cortical NPY neuron numbers increased after NT4 and BDNF transfection of a cocultured tectal explant innervated selectively by cortical layer V pyramidal neurons. The transcellular induction of NPY suggests a source-to-sink model for axonal transport and a local cortical redistribution of TrkB ligands to interneurons competent for NPY expression.
Synthesis and degradation of dinoflagellate plastid-encoded psbA proteins are light-regulated, not circadian-regulated
Authors: Wang Yunling , Jensen Lene , Højrup Peter , Morse David
Published: February 2005

In many dinoflagellate species, the plastid genome has been proposed to exist as a limited number of single-gene minicircles, and many genes normally found in the plastid genome are nuclear-encoded. Unlike the nuclear-encoded plastid-directed gene products whose expression is often regulated by the circadian clock, little is known about expression of minicircle genes. Furthermore, even the plastid location of the minicircles has recently been challenged. We have examined the incorporation
in vivo
of [
35
S]methionine into the proteins of purified plastids, and we find that several plastid proteins are labeled in the presence of cycloheximide but not chloramphenicol. One of these proteins, labeled in two different dinoflagellate species, was identified as psbA by Western blot analysis. Furthermore, this psbA has the expected physiological characteristics, because both synthesis and degradation are induced by light. We find no evidence for circadian control over either synthesis or degradation of psbA, unlike the several nuclear-encoded plastid-directed proteins studied. Finally, we find that levels of psbA protein or RNA do not change over a 24-h light-dark cycle, suggesting that this protein may not be involved in mediating the circadian rhythm in oxygen evolution rates. This demonstration is the first, to our knowledge, that minicircle genes encoding plastid proteins are translated in dinoflagellate plastids, and it suggests that a proteomic approach to characterizing the dinoflagellate plastid genome is feasible.
CB
2
cannabinoid receptor activation produces antinociception by stimulating peripheral release of endogenous opioids
Authors: Ibrahim Mohab M. , Porreca Frank , Lai Josephine , Albrecht Phillip J. , Rice Frank L. , Khodorova Alla , Davar Gudarz , Makriyannis Alexandros , Vanderah Todd W. , Mata Heriberto P. , Malan T. Philip
Published: February 2005

CB
2
cannabinoid receptor-selective agonists are promising candidates for the treatment of pain. CB
2
receptor activation inhibits acute, inflammatory, and neuropathic pain responses but does not cause central nervous system (CNS) effects, consistent with the lack of CB
2
receptors in the normal CNS. To date, there has been virtually no information regarding the mechanism of CB
2
receptor-mediated inhibition of pain responses. Here, we test the hypothesis that CB
2
receptor activation stimulates release from keratinocytes of the endogenous opioid β-endorphin, which then acts at opioid receptors on primary afferent neurons to inhibit nociception. The antinociceptive effects of the CB
2
receptor-selective agonist AM1241 were prevented in rats when naloxone or antiserum to β-endorphin was injected in the hindpaw where the noxious thermal stimulus was applied, suggesting that β-endorphin is necessary for CB
2
receptor-mediated antinociception. Further, AM1241 did not inhibit nociception in μ-opioid receptor-deficient mice. Hindpaw injection of β-endorphin was sufficient to produce antinociception. AM1241 stimulated β-endorphin release from rat skin tissue and from cultured human keratinocytes. This stimulation was prevented by AM630, a CB
2
cannabinoid receptor-selective antagonist and was not observed in skin from CB
2
cannabinoid receptor-deficient mice. These data suggest that CB
2
receptor activation stimulates release from keratinocytes of β-endorphin, which acts at local neuronal μ-opioid receptors to inhibit nociception. Supporting this possibility, CB
2
immunolabeling was detected on β-endorphin-containing keratinocytes in stratum granulosum throughout the epidermis of the hindpaw. This mechanism allows for the local release of β-endorphin, where CB
2
receptors are present, leading to anatomical specificity of opioid effects.
Fasting plasma zeaxanthin response to Fructus barbarum L. (wolfberry; Kei Tze) in a food-based human supplementation trial
Authors: Cheng Chung Yuen , Chung Wai Yuen , Szeto Yim Tong , Benzie Iris F. F.
Published: February 2005

Age-related macular degeneration (AMD) is a common disorder that causes irreversible loss of central vision. Increased intake of foods containing zeaxanthin may be effective in preventing AMD because the macula accumulates zeaxanthin and lutein, oxygenated carotenoids with antioxidant and blue light-absorbing properties. Lycium barbarum L. is a small red berry known as Fructus lycii and wolfberry in the West, and Kei Tze and Gou Qi Zi in Asia. Wolfberry is rich in zeaxanthin dipalmitate, and is valued in Chinese culture for being good for vision. The aim of this study, which was a single-blinded, placebo-controlled, human intervention trial of parallel design, was to provide data on how fasting plasma zeaxanthin concentration changes as a result of dietary supplementation with whole wolfberries. Fasting blood was collected from healthy, consenting subjects; fourteen subjects took 15 g/d wolfberry (estimated to contain almost 3 mg zeaxanthin) for 28 d. Repeat fasting blood was collected on day 29. Age- and sex-matched controls (n 13) took no wolfberry. Responses in the two groups were compared using the Mann–Whitney test. After supplementation, plasma zeaxanthin increased 2·5-fold: mean values on day 1 and 29 were 0·038 (sem 0·003) and 0·096 (sem 0·009) μmol/l (P<0·01), respectively, for the supplementation group; and 0·038 (sem 0·003) and 0·043 (sem 0·003) μmol/l (P>0·05), respectively, for the control group. This human supplementation trial shows that zeaxanthin in whole wolfberries is bioavailable and that intake of a modest daily amount markedly increases fasting plasma zeaxanthin levels. These new data will support further study of dietary strategies to maintain macular pigment density.
Evidence in support of a role for plant-mediated proteolysis in the rumens of grazing animals
Authors: Kingston-Smith A. H. , Merry R. J. , Leemans D. K. , Thomas H. , Theodorou M. K.
Published: February 2005

The present work aimed to differentiate between proteolytic activities of plants and micro-organisms during the incubation of grass in cattle rumens. Freshly cut ryegrass was placed in bags of varying permeability and incubated for 16 h in the rumens of dairy cows that had previously grazed a ryegrass sward, supplemented with 4 kg dairy concentrate daily. Woven polyester bags (50 μm pore size) permitted direct access of the micro-organisms and rumen fluid enzymes to the plant material. The polythene was impermeable even to small molecules such as NH3. Dialysis tubing excluded micro-organisms and rumen enzymes/metabolites larger than 10 kDa. DM loss was 46·3 % in polyester, 36·2 % in polythene and 38·1 % in dialysis treatments. It is possible that the DM loss within polythene bags occurred due to a solubilisation of plant constituents (e.g. water-soluble carbohydrates) rather than microbial attachment/degradation processes. The final protein content of the herbage residues was not significantly different between treatments. Regardless of bag permeability, over 97 % of the initial protein content was lost during incubationsin situ. Electrophoretic separation showed that Rubisco was extensively degraded in herbage residues whereas the membrane-associated, light-harvesting protein remained relatively undegraded. Protease activity was detected in herbage residues and bathing liquids after all incubationin situtreatments. Although rumen fluid contains proteases (possibly of plant and microbial origin), our results suggest that, owing to cell compartmentation, their activity against the proteins of intact plant cells is limited, supporting the view that plant proteases are involved in the degradation of proteins in freshly ingested herbage.
Molecular cloning and functional analysis of Photobacterium damselae subsp. piscicida haem receptor gene
Authors: Naka H , Hirono I , Aoki T
Published: February 2005

A haem receptor gene from Photobacterium damselae subsp. piscicida (formerly known as Pasteurella piscicida) has been cloned, sequenced and analysed for its function. The gene, designated as pph, has an open reading frame consisting of 2154 bp, a predicted 718 amino acid residues and exists as a single copy. It is homologous with the haem receptors of Vibrio anguillarum hupA, V. cholerae hutA, V. mimicus mhuA and V. vulnificus hupA at 32.7, 32.7, 45.6 and 30.9%, respectively, and is highly conserved, consisting of a Phe‐Arg‐Ala‐Pro sequence (FRAP), an iron transport related molecule (TonB) and a Asn‐Pron‐Asn‐Leu sequence (NPNL), binding motifs associated with haem receptors. As a single gene knockout mutant P. damselae subsp. piscicida was able to bind haem in the absence of pph, suggesting that other receptors may be involved in its iron transport system. This study shows that the P. damselae subsp. piscicida pph belongs to the haem receptor family, is conserved and that its iron‐binding system may involve more than one receptor.
Photo‐induced oxidative cross‐linking as a method to evaluate the specificity of protein–ligand interactions*
Authors: Lin H.‐J. , Kodadek T.
Published: February 2005

Abstract:  The isolation of protein‐binding synthetic molecules from combinatorial libraries or compound collections is now a common practice in chemical biology. An important, but underdeveloped, aspect of characterizing the binding properties of such molecules is their level of binding specificity. This is often evaluated by simply measuring the equilibrium binding affinity of the compound of interest with its target protein and comparing this value with its affinity to one or a few other purified proteins selected at random. These measurements may not reflect accurately the ability of the compound to seek out its target in a complex mixture of proteins such as a cell extract or serum. A more desirable alternative would be to develop solution assays that measure directly the binding of the molecule of interest to both target and competitor proteins in complex solutions. In this report, we evaluate a rapid and efficient photo‐triggered cross‐linking reaction for assessing binding specificity of synthetic molecules in protein mixtures. Using peptide–protein complexes, we demonstrate that this reaction provides an unbiased view of the peptide–protein contacts present in solution under a given set of conditions and thus is useful for assessing binding specificity. We also discuss the potential application of this chemistry to the related, but more difficult, problem of the identification of protein targets of bioactive molecules.
Crystalloid deposits in the kidney
Authors: KELLER LISA SUZANNE , FAULL RANDALL JAMES , SMITH PETER , SWIFT JEFFREY , BANNISTER KYM MALCOLM , OTTO SOPHIE , PEH CHEN AU
Published: February 2005

SUMMARY:  Light chain‐producing lymphoproliferative disorders such as multiple myeloma are frequently complicated by renal impairment. Typically, the renal biopsy of a patient with renal failure caused by multiple myeloma shows cast nephropathy, but occasionally crystals may be seen. We describe the case of a patient with acute renal failure caused by multiple myeloma in which, on renal and bone marrow biopsy, there were widespread crystalloid deposits. Crystalloid nephropathy is a very rare condition associated with multiple myeloma and other light chain‐secreting disorders. An underlying lymphoproliferative disorder should be considered in the differential diagnosis if crystalloid deposits are seen on a renal or other tissue biopsy.
Comparison of the effect of amphotericin B desoxycholate and amphotericin B colloidal dispersion on renal functions and renal morphology in rats
Authors: DOUBEK MICHAEL , MAYER JIRI , LAUSCHOVA IRENA , SCHEER PETER , KREJCIROVA LENKA , HORKY DRAHOMIR , DOUBEK JAROSLAV
Published: February 2005

Background and Aim: Amphotericin B (AmB) desoxycholate remains as one of the most efficacious agents currently available for the treatment of systemic fungal infections; however, amphotericin B colloidal dispersion (ABCD) has been developed because of AmB desoxycholate nephrotoxicity. The goal of our study was to compare the effect of administration of AmB desoxycholate and ABCD on renal functions and renal morphology in rats.

Results: Amophotericin B desoxycholate as well as ABCD causes damage to renal tubuli and polyuria. Amophotericin desoxycholate causes considerably more severe damage to tubuli than ABCD, but the morphological damage to renal glomeruli is minimal in both formulas. In tubular cells, AmB desoxycholate causes severe damage to mitochondria, vacuolation of cytoplasm, and increased values of volume density of peroxisomes.

Conclusion: None of these formulas causes a decrease in glomerular filtration in rats when animals are properly hydrated.
Seroprevalence of Helicobacter pylori in Chinese patients on continuous ambulatory peritoneal dialysis
Authors: LUI SING LEUNG , WONG WAI MAN , NG SUK YI , CHAN TAK MAO , LAI KAR NENG , LO WAI KEI
Published: February 2005

Backgrounds and Aims:  There is relatively little data on the seroprevalence of Helicobacter pylori in patients undergoing continuous ambulatory peritoneal dialysis (CAPD). This study aims at establishing the seroprevalence of and the factors associated with H. pylori infection in Chinese CAPD patients.

Methods:  All CAPD patients from a single dialysis centre were invited to participate in the study. Diagnosis of H. pylori infection was made serologically by the pylori DTect ELISA method. Dyspeptic symptoms were assessed by the Hong Kong Index of Dyspepsia (HKID) Questionnaire. Demographic, clinical and laboratory parameters were correlated with the H. pylori serology results.

Results:  One hundred and thirty‐six Chinese CAPD patients were included in the study. The mean age of the patients was 61.8 ± 12.5 years with a male to female ratio of 1:1.4. The mean duration of CAPD was 54 ± 42 months. Thirty‐five patients (26%) have positive serology against H. pylori. Nineteen patients had a HKID score of >16. There was no association between H. pylori seropositivity and dyspeptic symptoms (P = 0.62). Patients who were seropositive for H. pylori were significantly older (64.9 ± 9.5 years vs 60.7 ± 13.2 years, P < 0.05) and had lower KT/V‐values than patients who were seronegative for H. pylori (1.88 ± 0.3 vs 2.03 ± 0.3, P < 0.05). Patients with positive or negative H. pylori serological status did not differ in terms of demographic parameters (e.g. sex, duration of CAPD), clinical factors (e.g. bodyweight, body mass index, hepatitis status, use of H2 antagonists or proton pump inhibitors) and laboratory data (e.g. haemoglobin, serum urea, creatinine, albumin and parathyroid hormone levels).

Conclusions:  The seroprevalence of H. pylori infection among Chinese CAPD patients is 26%. Helicobacter pylori seropositivity is not associated with dyspepsia. Older age and lower KT/V‐values appear to be associated with the development of H. pylori seropositivity in our dialysis population.
Ethical and social issues of embryonic stem cell technology
Authors: Cregan K.
Published: February 2005

Therapeutic cloning is debated as a cure for a host of diseases in the developed world. The likely source for the materials for therapeutic cloning, human ova, would be poor women and women from the developing world. The ethics and potential social consequences inherent in this technology are fraught and encourage the com modification and abstraction of one of the fundamental conditions of human life. (Intern Med J 2005; 35: 126–127)
Prevalence of Migraine in Latin America
Authors: Morillo Luis E. , Alarcon Fernando , Aranaga Nayesca , Aulet Sara , Chapman Evelina , Conterno Lucien , Estevez Edmundo , Garcia‐Pedroza Felipe , Garrido Juanita , Macias‐Islas Miguel , Monzillo Paulo , Nunez Lilia , Plascencia Noel , Rodriguez Carlos , Takeuchi Yuri ,   Latin American Migraine Study Group
Published: February 2005

Objective.—To determine the 1‐year point prevalence of migraine among residents ≥15 years old in 12 Latin American urban communities, and record medical consultation preferences of the identified migraineurs.

Background.—Prevalence of migraine with or without aura in Latin American urban communities has not been established by large‐scale population studies.

Methods.—A validated face‐to‐face interview questionnaire based on International Headache Society criteria was completed for all headache sufferers within selected households, in a cross‐sectional study. The randomly selected populations were representative of urban communities from the six participating Latin American countries. The questionnaire used was identical in each of the six participating countries.

Results.—Of the 8618 people available for screening, 62% reported headache and 2637 completed interview questionnaires. Age‐adjusted 1‐year prevalence of migraine with or without aura for each country was (female/male, %): Argentina 6.1/3.8, Brazil 17.4/7.8, Colombia 13.8/4.8, Ecuador 13.5/2.9, Mexico 12.1/3.9, and Venezuela 12.2/4.7. Migraine prevalence was highest in women aged 30 to 50 years. In the year prior to the study, 42% of individuals interviewed and identified with migraine reported consulting a health professional about their headaches, most frequently (14%) a general practitioner. No previous diagnosis of migraine was reported by 65% of individuals with headache.

Conclusions.—In agreement with previous epidemiologic reports, migraine is also a common disorder in Latin American urban communities and predominantly affects women aged 30 to 50 years. Consultation preferences are also similar to those of previous reports.
Analysis of Optimal Phase Retardation of a Fringe Field-Driven Homogeneously Aligned Nematic Liquid Crystal Cell
Authors: Jung Song Hee , Kim Hyang Yul , Song Sung Hun , Kim Jae-Hyung , Nam Sang-Hee , Lee Seung Hee
Published: February 2005

We studied the optimal cell retardation value that shows the maximal transmittance in a fringe-field-driven homogeneously aligned (HA) nematic liquid crystal (LC) cell. When the LC with positive dielectric anisotropy is used, the transmittance is much higher than that of an in-plane-field-driven HA cell. The unexpected electrooptic behaviors are caused because the transmittance of light from a deformed LC in a white state cannot be explained using only the uniaxial medium model that describes an in-plane-field-driven HA cell.
Optical Second-Harmonic Generation Technique for Impulse Electric Field Measurements
Authors: Vasa Nilesh J. , Kuriaki Kazunori , Yokoyama Shigeru
Published: February 2005

A novel approach of an optical second-harmonic generation (SHG) technique combined with an electro-optic effect is proposed for measuring an impulse electric field. The experimental measurements combined with theoretical estimates show that even though the temperature control is a critical requirement, the SHG technique with nonlinear, electro-optic crystals, such as MgO:LiNbO3 and KTiOPO4, can be effectively used for electric field measurements by utilizing the phase matching condition.
Structure of an Oxygen-Related Defect Complex in SiC Studied with Electron Energy-Loss Spectroscopy
Authors: Muto Shunsuke , Sugiyama Hiroshi , Kimura Tomohiko , Tanabe Tetsuo
Published: February 2005

The atomic configuration of an oxygen-related defect complex in a SiC crystal was determined with the analyses of the extended energy-loss fine structure (EXELFS) and energy-loss near-edge structure (ELNES) in the electron energy-loss spectroscopy (EELS) associated with a transmission electron microscope (TEM). It was found that oxygen occupies a carbon site substitutionally in the SiC lattice, forming the O–V
C (carbon vacancy) complex. The structure is very similar to the so-called `A-center', which is known as an oxygen-vacancy complex in silicon. The present EXELFS/ELNES analysis can open up a wide range of possibilities for the structural analysis of point defects associated with light element impurities such as carbon, oxygen and nitrogen, complementary to XAFS techniques using synchrotron orbital radiation (SOR) sources.
Synchrotron X-Ray Topography of Lattice Undulation of Bonded Silicon-On-Insulator Wafers
Authors: Fukuda Kazunori , Yoshida Takayoshi , Shimura Takayoshi , Yasutake Kiyoshi , Umeno Masataka
Published: February 2005

Lattice undulation of Silicon-on-Insulator (SOI) layers of bonded SOI wafers was observed by synchrotron X-ray topography. Patterns observed on topographs depended on the thickness of the SOI layer, the camera distance between a specimen and an X-ray film, and the diffraction geometry of the Laue and Bragg cases. The dependence was interpreted as the effects of the geometrical relation in reciprocal space among the Ewald sphere, the reciprocal lattice vector, and the surface normal direction. To confirm the origin of the pattern formation, the topographic images were simulated in the framework of the kinematical diffraction theory. Based on the simulation, it was found that a granular pattern observed in the 115 Bragg case was due to the divergence/convergence effect of X-rays diffracted from the undulated SOI layer.
Reversibly Bendable Pyrolytic Graphite Film and its Electronic Properties
Authors: Take Hiroyoshi , Nishiki Naomi , Yoshimura Susumu , Yoshino Katsumi
Published: February 2005

A reversibly bendable graphite film has been prepared by the pyrolysis of a polyimide film at 2800°C. The graphite film can be bent reversibly and repeatedly by about 30° without inducing cracks on its surface. In addition, there is no variation of residual resistivity ratio and magnetoresistance, which are the index of the crystallinity, even with more than 100 bendings by about 30°. On the other hand by bending by more than 30° repeatedly, residual resistivity ratio and magnetoresistance slightly decreased. These results were interpreted by taking bending-induced defects in the graphite film into account.
Energy Control of Incident Ions to the Chamber-Wall by Using Push–Pull Bias (Phase-Controlled Bias) in UHF-ECR Etching System
Authors: Sumiya Masahiro , Yasui Naoki , Watanabe Seiichi
Published: February 2005

The effect of Push–Pull bias (phase-controlled bias) on the plasma potential and sputtering at the chamber-wall was investigated. It was found that the plasma potential could be controlled unrelated to the geometrical configuration of the chamber by using phase-controlled bias. The reason is that by using phase-controlled bias in the plasma with a magnetic field, the earth function of both electrodes facing each other can be controlled. Specifically, with the phase difference set to 180 degrees, the plasma potential was minimized and the decreased energy of incident ions to the chamber-wall reduced sputtering at the chamber-wall. Therefore, a stable process performance without particles caused by a sputtering at the chamber-wall, was expected by using Push-Pull bias in the dielectric UHF-ECR etching system.
Measurement of Plasma Radiation Fraction and Impurity Line Spectra in the Reversed Field Pinch Device, TPE-RX
Authors: Koguchi Haruhisa , Yagi Yasuyuki , Hirano Yoichi , Shimada Toshio , Sekine Shigeyuki , Sakakita Hajime
Published: February 2005

We report the plasma radiation loss power and impurity line emissions in the toroidal pinch experiment RX, TPE-RX under various plasma current (I
p) conditions. The emissivity at the off-axis chords is stronger than that at the central chord, and the plasma radiation profile is hollow. These trends are clearer at higher I
p. Although the plasma density increases with I
p, the radiation fraction remains constant at approximately 15% in the range of I
p studied. The input power increases with I
p. However, the increment cannot be explained entirely by the increment of the radiation loss power, which increases in proportion to the input power. At higher I
p, the emissions from impurities of both high and low atomic number (Z) increase. The increase of the line emission of these impurities reflects the increase of the plasma wall interaction.
Laser Flash Photolysis Studies on the Model System for Photo-Oxidation-Induced Polycondensation Polyimides with Fullerene C60
Authors: Shigemitsu Yasuo , Tajima Yusuke , Hoshino Mikio , Tezuka Yoshihiko , Takeuchi Kazuo
Published: February 2005

Laser flash photolysis studies were carried out to elucidate the quenching mechanism of the triplet state of fullerene C60 (3C60
*) by furan-substituted diimides, which are the model compounds for photosensitive polyimides based on the photo-oxidation-induced polycondensation (POP) reaction. The decay kinetics of transient 3C60
* triplet-triplet absorption at 740 nm revealed that the model diimides quenched 3C60
* in γ-butyrolactone, with the quenching rate constants, k
q(obsd), being determined to be on the order of 105 to 106 M-1·s-1. The free-energy changes for electron transfer from the model diimides to 3C60
*, ΔG
et, and the calculated electron transfer rate constants, k
q(calcd), were also evaluated from the Rehm-Weller equation using the oxidation potentials for the model diimides. The k
q(obsd) values were found to be, on the whole, correlated with ΔG
et and to be in fair agreement with the k
q(calcd) values. These results indicate that the quenching reaction occurs primarily by electron transfer from the diimide to 3C60
*. Furthermore, the k
q(obsd) value for benzyl 2-furoate, which constitutes a part of the model diimide molecule was found to be small compared with those for the model diimides. We therefore drew the conclusions that the electron transfer occurs predominantly from the benzimido moiety to 3C60
*, not from the furoate moiety and, consequently, the furoate moiety may not take part in electron transfer.
CuPc/C60 Solar Cells–Influence of the Indium Tin Oxide Substrate and Device Architecture on the Solar Cell Performance
Authors: Kwong Chung Yin , Djurišić Aleksandra B. , Chui P. C. , Chan Wai Kin
Published: February 2005

We investigated the influence of different indium tin oxide (ITO) surface treatments on the performance of organic solar cells with different device architectures. Two types of devices (CuPc in contact with ITO treated with different treatments and C60 in contact with ITO treated with different treatments) were fabricated. The surfaces of CuPc and C60 layers deposited on ITO substrates treated with different surface treatments were examined using atomic force microscopy. The devices were characterized by measuring current-voltage characteristics in the dark and under AM1 illumination. We found that a one order of magnitude improvement in the AM1 power conversion efficiency for ITO/CuPc/C60/Al cells can be achieved for optimal ITO surface treatment, while ITO/C60/CuPc/Cu devices exhibit less sensitivity to surface treatments. Moreover, these devices exhibit better performance compared to ITO/CuPc/C60/Al devices. The observed differences in sensitivity to surface treatments were attributed to difference in the dependence of the film surface on ITO surface morphology for CuPc and C60.
Structure of the Sb/Si(112) Surface Studied by Low Energy Electron Diffraction
Authors: Cho Eun-Sang , Park Jung-Woon , Hur Hoon , Kim Nam-Hong , Baik Jae-Yoon , Jeon Cheol-Ho , Hwang Chan-Cuk , An Ki-Seok , Park Chong-Yun
Published: February 2005

We have investigated the Sb-induced phase transition of the reconstructed Si(112) surface by low energy electron diffraction (LEED) and X-ray photoelectron spectroscopy (XPS). A sharp sixfold hexagonal LEED pattern was observed when Sb was deposited on the clean Si(112) surface at 300°C, corresponding to the bulk-terminated 1×1 structure of the Si(111) surface. From the LEED pattern and the XPS results, we suggest a surface structure corresponding to the LEED pattern with (111) - 1×1 + weak 5×1 spots for the Sb/Si(112) surface.
Compensating a Twisted Nematic Liquid Crystal Display with Matched Wavelength Dispersion Retarders
Authors: Montbach Erica N. , Bos Philip J. , Gambogi William J.
Published: February 2005

We show that holographic retarders using form birefringence can be designed to allow accurate matching of the dispersion of a liquid crystal device. A twisted nematic (TN) liquid crystal display (LCD) is compensated using stacked, dispersion matched, holographic retarders and the results are compared with a TN-LCD compensated by a single, splayed optic axis retarder on both sides of the LC layer. The new compensator design is shown to have excellent qualities, and the potential to surpass previous designs.
Close Relationship between Bending-Electrostrictive Response and Space Charge Distribution in a Polyurethane Film
Authors: Watanabe Masashi , Hirai Toshihiro
Published: February 2005

The object of our study was to clarify the mechanism of the bending-electrostrictive response of a polyurethane film. We investigated the mechanism using the pulsed electroacoustic method for measuring the space charge distribution in the film. The measurements revealed a similarity between the time courses of the bending-electrostrictive response and the space charge accumulation. That is, the film gradually bent to the cathode side during the first electric-field application to a virgin sample. However, it quickly bent during the succeeding second application. On the other hand, the measurement of the space charge showed that a negative space charge gradually accumulated inside the anode during the first application. However, it quickly accumulated during the second application. Time plots of the bending deformation and the space charge density clearly showed the above similarity in the response profile. Such a similarity suggests that the space charge is closely related to the bending electrostriction mechanism.
Study of the Transient Phenomenon during Homeotropic to Planar Transition in Cholesteric Liquid Crystal Cells
Authors: Yao I-An , Wu Jin-Jei , Chen Shu-Hsia
Published: February 2005

The transient behavior of homeotropic-planar relaxation in surface stabilized cholesteric liquid crystals bounded by parallel substrates has been investigated both experimentally and numerically. By monitoring the evolution of transient transmittance, we observe that the homeotropic-planar relaxation after the electric field is switched off occurs via a transient planar state. The effect of bias waveform on the relaxation process is also studied. On the basis of this knowledge, we design a driving waveform to reduce the relaxation time.
Study of Lead Magnesium Niobate–Lead Titanate Ceramics for Piezo-Actuator Applications
Authors: Kumar Pawan , Singh Sarabjit , Thakur Om Prakash , Prakash Chandra , Goel Tara Chand
Published: February 2005

Structural, dielectric, ferroelectric and piezoelectric properties of lead magnesium niobate–lead titanate, PMN–PT (66:34), prepared at different sintering temperatures (1150–1250°C) are discussed for actuator applications. System sintered at 1200 and 1250°C showed better perovskite phase stabilization and higher values of dielectric constant (ε
r). Remnant polarization (P
r) was found to be higher (45 µC/cm2) for the system sintered at 1250°C. The piezoelectric coefficients, d
33, d
31, d
h and strain induced in the system by a large electric field were found to be sintering temperature dependent. Hysteresis free strain behavior of the system sintered at 1200°C showed the suitability of this material for actuator applications.
Characterization of the Sn Doped In2O3 Film Prepared by DC Magnetron Sputter Type Negative Metal Ion Beam Deposition
Authors: Kim Daeil , Ma Dongjoon , Lee Naesung
Published: February 2005

Transparent conducting indium tin oxide (ITO) films were prepared on a glass substrate by DC magnetron sputter type negative ion source from a target of a mixture of In2O3 (90%) and SnO2 (10%). In order to investigate the influence of cesium (Cs) partial pressure (P
Cs) on the optoelectronic property of ITO films, the P
Cs was varied from 1×10-3 to 2.2×10-3 Pa. The O2/Ar flow rate, working pressure, power density, and substrate temperature were kept constant at 3.6%, 9×10-2 Pa, 2.5 Wcm-2 and 70°C, respectively. By optimizing the P
Cs at 1.7×10-3 Pa, transparent (transmission ∼81% at 550 nm) and conducting (resistivity ∼4.3×10-4 Ωcm) ITO films were prepared. Atomic force microscopy (AFM) images showed that the surface morphology also varied significantly with P
Cs and that the lowest surface rms roughness was 0.6 nm measured at P
Cs=1.7×10-3 Pa. XPS measurement showed that the Cs concentration in the ITO films was less than 0.2 at%.
Scintillating Track Image Camera-SCITIC
Authors: Sato Akira , Asai Jyunkichi , Ieiri Masaharu , Iwata Soma , Kadowaki Tetsuhito , Kurosawa Maki , Nagae Tomohumi , Nakai Kozi
Published: February 2005

A new type of track detector, scintillating track image camera (SCITIC) has been developed. Scintillating track images of particles in a scintillator are focused by an optical lens system on a photocathode on image intesifier tube (IIT). The image signals are amplified by an IIT-cascade and stored by a CCD camera. The performance of the detector has been tested with cosmic-ray muons and with pion- and proton-beams from the KEK 12-GeV proton synchrotron. Data of the test experiments have shown promising features of SCITIC as a triggerable track detector with a variety of possibilities.
Rydberg Series in the Photoionization of the Excited 1s22s3s1,3SeStates of Atomic Beryllium
Authors: Kim Dae-Soung
Published: February 2005

Photoionization cross sections for ionization to Be+(2s, 2p, 3s, 3p, and 3d) states from the excited 2s3s1,3Sstates of atomic beryllium, which contain several autoionizing Rydberg series of resonances converging to the Be+(2p, 3s, 3p, and 3d) states, have been calculated by an enhanced noniterative eigenchannel R-matrix method. Lower members of the Rydberg series of resonances withn≤10 are identified along with the calculated resonance positionsEr, effective quantum numbersn*, and widths Γ. The present results are compared with those of previous calculation and very good agreement between them is noted. There is excellent agreement between length and velocity gauges in the present calculation.