bluuebunny/crossref_metadata_2025 huggingface dataset:
Retinal abnormalities associated with the G90D mutation in opsin
Authors: Naash Muna I. , Wu Ting‐Huai , Chakraborty Dibyendu , Fliesler Steven J. , Ding Xi‐Qin , Nour May , Peachey Neal S. , Lem Janis , Qtaishat Nasser , Al‐Ubaidi Muayyad R. , Ripps Harris
Published: August 2004

Several mutations in the opsin gene have been associated with congenital stationary night blindness, considered to be a relatively nonprogressive disorder. In the present study, we examined the structural and functional changes induced by one of these mutations, i.e., substitution of aspartic acid for glycine at position 90 (G90D). Transgenic mice were created in which the ratio of transgenic opsin transcript to endogenous was 0.5:1, 1.7:1, or 2.5:1 and were studied via light and electron microscopy, immunocytochemistry, electroretinography (ERG), and spectrophotometry. Retinas with transgenic opsin levels equivalent to one endogenous allele (G0.5) appeared normal for a period of about 3–4 months, but at later ages there were disorganized, shortened rod outer segments (ROS), and a loss of photoreceptor nuclei. Higher levels of G90D opsin expression produced earlier signs of retinal degeneration and more severe disruption of photoreceptor morphology. Despite these adverse effects, the mutation had a positive effect on the retinas of rhodopsin knockout (R−/−) mice, whose visual cells fail to form ROS and rapidly degenerate. Incorporation of the transgene in the null background (G+/−/R−/− or G+/+/R−/−) led to the development of ROS containing G90D opsin and prolonged survival of photoreceptors. Absorbance spectra measured both in vitro and in situ showed a significant reduction of more than 90% in the amount of light‐sensitive pigment in the retinas of G+/+/R−/− mice, and ERG recordings revealed a >1 log unit loss in sensitivity. However, the histological appearances of the retinas of these mice show no significant loss of photoreceptors and little change in the lengths of their outer segments. These findings suggest that much of the ERG sensitivity loss derives from the reduced quantal absorption that results from a failure of G90D opsin to bind to its chromophore and form a normal complement of light‐sensitive visual pigment. J. Comp. Neurol. 478:149–163, 2004. © 2004 Wiley‐Liss, Inc.
A model of sex‐based social stability
Authors: Koch Andreas , Tvede Mich
Published: August 2004

For some time theoretical biologists have been discussing the origin of sexes, which seems somewhat puzzling as there are intrinsic inefficiencies for a species to produce males and females, rather than hermaphrodites. We propose that part of the explanation of this may be the additional social stability that sexes offer. We use notions from cooperative game theory to show that for hermaphrodites, it may be impossible for a social group to find a stable set of partnerships. The existence of such a stable set of partnerships is, however, guaranteed for species with both males and females. © 2004 Wiley Periodicals, Inc. Complexity 9: 52–56, 2004
Some Researches in Plasma Physics
Authors: Allen J. E.
Published: August 2004

A brief review is given of a number of topics in plasma physics that the author has worked on in Liverpool, Harwell, Rome and Oxford. These include both experimental and theoretical contributions to the subject. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Turbulence and Anomalous Transport in Magnetized Plasmas: Hints from the Reversed Field Pinch Configuration
Authors: Antoni V. , Bergsåker H. , Cavazzana R. , Carbone V. , Drake J. , Martines E. , Regnoli G. , Serianni G. , Spada E. , Spolaore M. , Vianello N.
Published: August 2004

The properties of plasma turbulence in the outer region of the Reversed Field Pinch experiments RFX and EXTRAP‐T2R are reviewed. The statistical properties of fluctuations in the range of scales relevant for transport are presented. The observation of coherent structures emerging from the background turbulence and their interpretation in terms of vortices is reported. The interplay between these structures and the mean E×B flow of the plasma is demonstrated with emphasis to the action on the preferential rotation direction. The effect on the particle transport induced by the background turbulence and by the structures is discussed. Finally the methods tested to control turbulence and to mitigate the related transport are illustrated and discussed. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Practical Plasma Immersion Ion Implantation for Stress Regulation and Treatment of Insulators
Authors: Bilek M. M. M. , McKenzie D. R. , Tarrant R. N. , Oates T. W. H. , Ruch P. , Newton‐McGee K. , Shi Yang , Tompsett D. , Nguyen H. C. , Gan B. K. , Kwok D. T.
Published: August 2004

Plasma immersion ion implantation has been attracting the interest of research groups around the world over the last two decades. The technique has been developed to the stage where it is a well‐established technique for a number of materials processing applications, such as plasma nitriding. Recent research has focussed on developing the method for a range of new applications, including stress regulation and control of microstructure, as well as surface treatment of insulators. Recent developments in these technologically important applications are discussed in this paper. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Generation of Thin Surface Plasma Layers for Atmospheric‐Pressure Surface Treatments
Authors: Černák M. , Ráhel' J. , Kováčik D. , Šimor M. , Brablec A. , Slavíček P.
Published: August 2004

Thin layers of atmospheric‐pressure non‐equilibrium plasma can be generated by pulse surface corona discharges and surface barrier discharges developing on the treated surfaces or brought into a close contact with the treated surfaces. Plasma sources based on these discharge types have the potential of meeting the basic on‐line production requirements in the industry and can be useful for a wide range of surface treatments and deposition processes including continuous treatment of textiles. Comparing with atmospheric pressure glow discharge sources, the potential advantages of these plasma sources include their simplicity, robustness, and capability to process in a wide range of working gases. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Experimental Studies of MHD Dynamics in a RFP Magnetically Confined Plasma
Authors: Drake J. R. , Malmberg J.‐A. , the EXTRAP T2R Team
Published: August 2004

Studies of non‐linear dynamics of MHD tearing modes in the EXTRAP reversed‐field pinch experiments [1] have demonstrated such phenomena as mode rotation, phase‐locking and wall locking. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Two‐DimensionalKinetic and Three‐Dimensional Fluid‐Radiation Transport Simulations of Plasma Display Panel
Authors: Yang S. S. , Lee J. K. , Ko S. W. , Kim H. C. , Shon J. W.
Published: August 2004

Using fluid and kinetic simulation codes, we investigated ion angle distributions in a PDP cell. We also compared our fluid simulation results with experimental data to prove the accuracy of our codes and suggested new PDP cell structure. Kinetic simulation results shows that most ions impinge on the MgO surface at the cathode region with the incident angles in the range of 10° ∼ 30°. Our simulation results from 2‐D and 3‐D fluid codes showed good agreements in the distribution of excited Xe atom density compared to the experimental data measured by laser absorption spectroscopy. Using these fluid codes, we suggested Front Address PDP cell structure. This structure has address electrode on the upper substrate and shows the improvement of luminous efficiency about 2 times in comparison with conventional model because of the arch‐shaped long discharge path between two sustain electrodes. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Liesegang rings in hemorrhagic urine
Authors: Misselevich Ines , Zlotnik Marina , Boss Jochanan H.
Published: August 2004

Myriad Liesegang rings were encountered in the urine of a 43‐year‐old patient who was diagnosed as having idiopathic hematuria, emanating from the left ureter or kidney. Erythrocytes and the Liesegang rings spontaneously disappeared from the urine within 4 weeks. We are unaware of a report of a similar observation. Lack of descriptions may be due to underreporting or reflect true rarity of Liesegang rings in the urine. It is suggested that Liesegang rings may precipitate in the hemorrhagic urine as they do in diverse blood‐imbibed tissues. Diagn. Cytopathol. 2004;31:173–174. © 2004 Wiley‐Liss, Inc.
Cytologic features of recurrent lymphoma involving the urinary bladder
Authors: Quinn Adam M. , Flanigan Robert , Sienko Anna , Wojcik Eva M.
Published: August 2004

Recurrent lymphoma of the bladder only occasionally presents with genitourinary symptoms, and there are very few cases in the literature reporting the cytologic findings of involvement of the urinary bladder by lymphoma. We report the findings from a case of diffuse large B‐cell lymphoma with immunoblastic morphology that was identified in a bladder barbotage specimen of a 77‐year‐old man who presented with recurrent urinary tract infection and hematuria. We describe the cytomorphological features of lymphoma cells in the urine and discuss the differential diagnoses. Correlation of cytologic findings with immunohistochemical results is crucial in the diagnosis of lymphoma involving the urinary bladder. Diagn. Cytopathol. 2004;31:185–188. © 2004 Wiley‐Liss, Inc.
Nevus‐cell aggregates in lymph nodes: Fine‐needle aspiration cytologic findings and resulting diagnostic difficulties
Authors: Zaharopoulos Paul , Hudnall S. David
Published: August 2004

We report a case of nodal nevus present in enlarged lymph nodes with changes of dermatopathic lymphadenopathy sampled by fine‐needle aspiration (FNA) cytology prior to clinical evaluation of the patient. This lymph node pathology was established later by lymph node excisional biopsy, by which along with a skin biopsy the dermatopathic lymphadenopathy was tentatively attributed to early mycosis fungoides. The FNA revealed fairly atypical melanotic tissue from the dermatopathic lymphadenopathy along with nodules of uniform melanocytic nevoid cells, the presence of which in combination with the dermatopathic atypical tissue provided a tentative diagnosis of metastatic melanoma of unknown primary, with the diagnosis of nodal nevus presented as a less likely possibility. This is to our knowledge the first cytologic report on FNA of nodal nevus, which besides presenting cytologic findings of this entity highlights some of the problems related to providing an accurate diagnosis, if this exceptionally unusual pathologic entity is encountered in lymph nodes sampled for enlargement from pathologies unrelated to this entity. The subject of nevus changes in lymph nodes is briefly discussed. Diagn. Cytopathol. 2004;31:180–184. © 2004 Wiley‐Liss, Inc.
Pap test in a high‐risk population comparison of conventional and liquid‐base cytology
Authors: Utagawa Maria Lúcia , Miranda Pereira Sônia Maria , Makabe Sérgio , Yoshié Sakamoto Maeda Marina , Marques José A. , Santoro Carmen L.F. , Di Loreto Celso , Aguiar Luciana Silva , Pitolli Janaina Érika , Das Dores Gerson Botacini , Castelo Adauto , Filho Adhemar Longatto
Published: August 2004

Liquid‐based cytology (LBC) is believed to have better sensitivity than conventional smears (CSs) and offers the possibility to perform molecular assay. The goal of this work was to study the performance of CS and LBC in a high‐risk population and to compare the results with the hybrid capture (HC) II for high‐risk human papillomavirus (HPV). Samples were collected from selected women with clinical suspicions of low genital tract lesion at Pérola Biygnton Hospital (São Paulo, Brazil). After CS preparation, the brush was introduced in the endocervix and a new sample was collected and rinsed in the preservative medium of the system. The residual material was used to HC2. From 925 cases, LBC was unsatisfactory in 4 (1.51%) cases and CS was unsatisfactory in 100 cases (10.81%); among theses cases HC2+ reactions was observed in 54 (54%) CSs and 3 (21.4%) LBCs. Considering cases with atypia of undetermined significance (squamous and glandular), 85 (77.27%) cases from LBC and 44 (86.4%) from CS were positive for HC2 assay for high‐risk DNA‐HPV. The difference among the methods was not significant (P < 0.38). The diagnosis improvement of LBC in comparison with CS was 86% in satisfactory samples, 92.76% in undetermined atypical lesions (including glandular), 83% in positive low‐grade squamous intraepithelial lesions (LSIL+), and 86.84% in high‐grade SIL+ (HSIL+). HC2+ reactions were observed in 144 CS cases and 266 LBC cases with abnormalities. Our results have showed that LBC was superior to CS in a high‐risk population to detect lesions with high concordance with HC2+ reactions; CSs also exhibit a high concordance with HC2 assay but with inferior performance to detect lesions. Diagn. Cytopathol. 2004;31:169–172. © 2004 Wiley‐Liss, Inc.
Effects of diet and handling on initiation of independent ingestion in rats
Authors: Doerflinger Alicia , Swithers Susan E.
Published: August 2004

The present study examined the effects of dietary manipulation on the age of onset of weaning in rat pups. In Experiment 1, female rats were placed on a standard chow (SC) or high‐fat (HF) diet 1 week following mating. Pups were weighed daily from birth to Day 12, then animals were placed into specialized cages for separate recording of food intake of pups and dams. Pups were offered the same diet as their dam, and food intake and body weight were determined twice daily until Day 25. The results demonstrated that pups reared by dams fed the HF diet initiated independent ingestion on Day 16, approximately 24 hr before pups reared by dams fed the SC diet. There were no differences in body weight in pups across the two diets. While few differences were noted across diets in pups' or dams' behavior, HF pups appeared to demonstrate a delay in the establishment of circadian patterns of food intake. In Experiment 2, all dams were maintained on an SC diet until the day after parturition. At that time, dams and litters were placed into specialized cages and divided into four groups: HF/HF, HF/SC, SC/SC, and SC/HF (dam's diet/pup's diet, respectively). The results demonstrated that dams given the HF diet had pups that initiated food intake approximately 2 days before the pups of dams given the SC diet. In addition, pups offered the HF diet, independent of the dam's diet, initiated food intake approximately 0.8 days prior to pups offered the SC diet. Further, by Day 12, HF dams had pups that were heavier than SC dams. The results suggest that the onset of weaning in rats is affected by maternal diet and the weaning diet available to the pup. © 2004 Wiley Periodicals, Inc. Dev Psychobiol 45:72‐82, 2004.
Preamble: New dimensions in evaluation
Authors: Chelimsky Eleanor
Published: August 2004

The president of the American Evaluation Association takes stock of progress in the application of evaluation findings to decision making and in the development of evaluation methods. She emphasizes the importance of credibility—through eclecticism in method and clarity of presentation—and of realism, sensitivity, and independence in relationships with decision makers.
Evaluating the effectiveness of poverty alleviation programs
Authors: Squire Lyn
Published: August 2004

This chapter discusses the necessary ingredients for rigorous evaluation of poverty alleviation programs in developing countries. It confronts such poverty‐specific issues as empowerment of the poor, beneficiary participation in design and implementation of programs, and beneficiary assessments.
Using evaluation indicators to track the performance of education programs
Authors: Psacharopoulos George
Published: August 2004

The nature of performance criteria and the timing of evaluation are crucial determinants of the relevance and accuracy of findings for education and training systems. The author proposes specific indicators adapted to different evaluation situations and stresses the importance of conducting ex ante and impact rather than just input evaluations.
The housing indicators program: A model for evaluation research and policy analysis?
Authors: Mayo Stephen K.
Published: August 2004

The author draws from the lessons of the ongoing Housing Indicators Program to provide a framework for developing better performance indicators and improving the development impact of housing policies and programs.
Volatility and commodity price dynamics
Authors: Pindyck Robert S.
Published: August 2004

Commodity prices are volatile, and volatility itself varies over time. Changes in volatility can affect market variables by directly affecting the marginal value of storage, and by affecting a component of the total marginal cost of production, the opportunity cost of producing the commodity now rather than waiting for more price information. I examine the role of volatility in short‐run commodity market dynamics and the determinants of volatility itself. I develop a structural model of inventories, spot, and futures prices that explicitly accounts for volatility, and estimate it using daily and weekly data for the petroleum complex: crude oil, heating oil, and gasoline. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:1029–1047, 2004
Predicting financial volatility: High‐frequency time‐series forecasts vis‐à‐vis implied volatility
Authors: Martens Martin , Zein Jason
Published: August 2004

Recent evidence suggests option implied volatilities provide better forecasts of financial volatility than time‐series models based on historical daily returns. In this study both the measurement and the forecasting of financial volatility is improved using high‐frequency data and long memory modeling, the latest proposed method to model volatility. This is the first study to extract results for three separate asset classes, equity, foreign exchange, and commodities. The results for the S&P 500, YEN/USD, and Light, Sweet Crude Oil provide a robust indication that volatility forecasts based on historical intraday returns do provide good volatility forecasts that can compete with and even outperform implied volatility. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:1005–1028, 2004
Co‐vaccination with adeno‐associated virus vectors encoding human papillomavirus 16 L1 proteins and adenovirus encoding murine GM‐CSF can elicit strong and prolonged neutralizing antibody
Authors: Liu Dai‐Wei , Chang Junn‐Liang , Tsao Yeou‐Ping , Huang Chien‐Wei , Kuo Shu‐Wen , Chen Show‐Li
Published: August 2004

Non‐infectious human papillomavirus‐like particles (VLPs), encoded by the major capsid gene L1, have been shown to be effective as vaccines to prevent cervical cancer. We have developed the genetic immunization of the L1 gene to induce a neutralizing antibody. We constructed and generated a recombinant adeno‐associated virus encoding human papillomavirus (HPV) 16 L1 protein that could form virus‐like particles in transduced cells. Previous reports have demonstrated that the formation of VLP is necessary to induce high titers of neutralizing antibodies to protect an animal from viral challenge. Therefore, we carried out a single intramuscular (i.m.) injection with recombinant adeno‐associated virus encoding HPV‐16 L1 protein (rAAV‐16L1) in BALB/c mice, which ultimately produced stronger and more prolonged neutralizing L1 antibodies, when compared to the DNA vaccine. Immunohistochemistry showed that the accumulation of antigen presenting cells, such as macrophages and dendritic cells, in rAAV‐16L1 and L1 DNA‐injected muscle fibers may be due to the L1 protein expression, but not to AAV infection. When compared to the L1 VLP vaccine, however, the titers of neutralizing L1 antibodies induced by VLP were higher than those induced by rAAV‐16L1. Co‐vaccinating with rAAV‐16L1 and adenovirus encoding murine GM‐CSF (rAAV‐16L1/rAd‐mGM‐CSF) induced comparable higher levels of neutralizing L1 antibodies with those of VLP. This implies that a single i.m. co‐injection with rAAV‐16L1/rAd‐mGM‐CSF can achieve the same vaccine effect as a VLP vaccine requiring 3 booster injections.
Inhibition of immunosuppressive effects of melanoma‐inhibiting activity (MIA) by antisense techniques
Authors: Jachimczak Piotr , Apfel Rainer , Bosserhoff Anja‐Kathrin , Fabel Klaus , Hau Peter , Tschertner Ines , Wise Petra , Schlingensiepen Karl‐Hermann , Schuler‐Thurner Beatrix , Bogdahn Ulrich
Published: August 2004

Melanoma inhibitory activity (MIA) is an 11 kD protein secreted by malignant melanomas. Recent studies revealed an interaction of MIA with epitopes of extracellular matrix proteins including fibronectin. Structural homology of MIA with the binding sites of α4β1 integrin results in complex interactions of MIA with molecules binding to α4β1 integrin. As cells of the immune system express α4β1 integrins (VLA‐4), we investigated whether MIA may modulate the function of human leukocytes. Here we describe the effects of MIA on the activation of human PBMCs and auto‐/allogeneic lymphokine‐activated killer cell (LAK) cytotoxicity in human MIA‐negative glioma cell lines and MIA‐positive melanoma cell lines in vitro. MIA inhibits PHA‐ or IL‐2‐induced human PBMC proliferation in a dose‐dependent manner up to 63% (3H‐Tdr incorporation) and 59% (cell count), respectively, when added to the cell culture prior to mitogen stimulation. In addition, both autologous (GL and HW) and allogeneic (HTZ‐17, HTZ‐243 and HTZ‐374) antitumor LAK cytotoxicity was reduced by the addition of exogenous rhMIA (500 ng/ml, f.c.). Consequently, endogenous inhibition of MIA expression in human melanoma cells by MIA‐specific phosphorothioate antisense oligonucleotides enhanced the autologous LAK‐cell activity to the same level as observed in MIA‐negative human HMB melanoma cells expressing an MIA‐antisense construct. Our results indicate that MIA may contribute to immunosuppression frequently seen in malignant melanomas by inhibiting cellular antitumor immune reactions. Antagonization of MIA activity using antisense techniques may represent a novel therapeutic strategy for treatment of malignant melanomas.
In vitro analysis of anionic collagen scaffolds for bone repair
Authors: Moreira Patricia L. , An Yuehuei H. , Santos Arnaldo Rodrigues , Genari Selma Candelária
Published: August 2004

Collagen has been extensively described as a beneficial material in bone tissue engineering due to its biocompatibility, biodegradability, low antigenicity, and high tensile strength. However, collagen scaffolds in their pure form have some drawbacks and improvements in the physical, chemical, and biologic properties of collagen are necessary to overcome those inadequacies. Recently, the selective hydrolysis of carboxyamides of asparagine and glutamine residues of collagen has been employed to increase the number of negative sites and enhance the piezoelectric properties of collagen. Anionic collagen scaffolds were prepared by use of a hydrolysis treatment for either 24 h [bovine pericardium (BP 24)] or 48 h (BP 48). Bovine osteoblasts were cultured on them and on native matrices to understand the cellular interactions responsible for the good osteoconductivity and biocompatibility reported with in vivo tests. Based on the data obtained on cell adhesion, alkaline phosphatase (ALP) and extracellular matrix macromolecule production, and cellular proliferation through histological analysis, we may conclude that the materials tested reveal sufficient biocompatibility level for bone repair. Further, the evidence of some connection between ALP activity and the mineralization process should be emphasized. BP 48 presented the most promising results stimulating in vitro mineralization, ALP production, and possible osteoblast differentiation. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 71B: 229–237, 2004
Early diagnosis of lung cancer by detection of tumor liberated protein
Authors: Tarro Giulio , Perna Antonio , Esposito Ciro
Published: August 2004

Tumor liberated protein (TLP) is a protein that can be used to reveal the early development of a tumor. Besides being formed in the tumor, TLP is released in the blood when a patient starts producing cancer cells, which in turn enables the physician to intervene at a stage when the cancer is operable. To date, the available studies of tumor markers in lung cancer patients are CEA, NSE, TPA, Chromogranine, CA125, CA19‐9, and Cyfra 21‐1. The sensitivity and specificity for serum markers ranges between 50 and 90%, depending on the study and the clinical samples analyzed. Most of these markers show an increased rate of positivity as the stage advances. There are very limited data on TLP to draw any firm conclusion regarding the diagnostic value of this marker. TLP has been detected in 53.1% of non‐small cell lung cancer (NSCLC) patients (N = 534) with 75% being positive in the early stage (stage I) and dropping to 45% in the late stage (stage IV). However, 7.6% blood donor sera and 17.4% chronic lung disease sera have also tested positive. In a confirmation study, the specificity was 89.94% and the sensibility was 63.63% from stage III to IV NSCLC patients. In an initial study of TLP as a marker for early detection in stage I, NSCLC patients showed a sensitivity of 66.7% and a specificity of 80% for TLP compared to a sensitivity of 33.3% for CA19‐9, 11.1% for Cyfra 21‐1 and CA125, and 0% for CEA; the specificity for all four of the latter markers was 100%. Using immunohistochemical analysis with peroxidase anti‐peroxidase (PAP), we observed that NSCLC cells were positive; we used the specific rabbit antiserum to TLP, which turned out negative in the presence of 1 mg/ml of the synthetized peptide. The pre‐serum was also negative. The same reactivity was found early in the modified epithelial cells of interstitial lung fibrosis and might be a predictive marker of cell transformation. The site of the peroxidase positivity was cytoplasmic, of diffuse and/or granular type. © 2004 Wiley‐Liss, Inc.
Cell volume and the regulation of apoptotic cell death
Authors: Lang Florian , Gulbins Erich , Szabo Ildiko , Lepple‐Wienhues Albrecht , Huber Stephan M. , Duranton Christophe , Lang Karl S. , Lang Philipp A. , Wieder Thomas
Published: August 2004

Apoptosis is a physiological mechanism allowing for the removal of abundant or potentially harmful cells. The hallmarks of apoptosis include degradation of cellular DNA, exposure of phosphatidylserine at the outer leaflet of the cell membrane and cell shrinkage. Phosphatidylserine exposure favours adhesion to macrophages with subsequent phagocytosis of the shrunken apoptotic particles. The interaction of cell volume regulatory mechanisms and apoptosis is illustrated in two different model systems, i.e. (a) lymphocyte apoptosis following stimulation of CD95 receptor and (b) erythrocyte apoptosis upon cell shrinkage. (a) Triggering of CD95 in Jurkat T lymphocytes is paralleled by activation of cell volume regulatory Cl− channels, inhibition of the Na+/H+ exchanger and osmolyte release. The latter coincides with cell shrinkage, DNA fragmentation and phosphatidylserine exposure. CD95 stimulation leads to early inhibition of the voltage gated K+ channel Kv1.3, which may contribute to the inhibition of the Ca2+ release activated Ca2+ channel ICRAC. (b) Osmotic shock of erythrocytes activates a cell volume regulatory cation conductance allowing the entry not only of Na+ but of Ca2+ as well. Increased cytosolic Ca2+ stimulates a scramblase which disrupts the phosphatidylserine asymmetry of the cell membrane, leading to phosphatidylserine exposure. The cation conductance is further activated by oxidative stress and energy depletion and inhibited by Cl−. Shrinkage of erythrocytes stimulates in addition a sphingomyelinase with subsequent formation of ceramide which potentiates the effect of cytosolic Ca2+ on phosphatidylserine. In conclusion, cell volume‐sensitive mechanisms participate in the triggering of apoptosis following receptor stimulation or cell injury. Copyright © 2004 John Wiley & Sons, Ltd.
Chaperonin function—effects of crowding and confinement
Authors: Martin Jörg
Published: August 2004

Chaperonins assist in the acquisition of native protein structure in the cell by providing a shielded environment for a folding polypeptide chain, generated by the interior surface of their cylindrical structure. The folding chain is isolated from the highly crowded cytoplasm, but at the same time confined within the chaperonin folding cage. Both confinement and macromolecular crowding can affect folding kinetics and yields, the modus operandi of chaperonins and their interaction with their protegés. Recent experimental data, as well as computer simulations, provide increasing evidence that the particular physico‐chemical conditions prevailing in the cellular interior have to be taken into account when trying to unravel the processes of cellular protein folding. Copyright © 2004 John Wiley & Sons, Ltd.
Fluorescence anisotropy as a probe to study tracer proteins in crowded solutions
Authors: Zorrilla Silvia , Rivas Germán , Lillo M. Pilar
Published: August 2004

Fluorescence anisotropy has been widely used to study the dynamics and interactions of biomolecules in diluted solutions. Comparable studies on single tracer macromolecules at the cellular level are now feasible because of the recent development of non‐invasive fluorescence markers, like the growing family of the green fluorescence proteins (GFPs), and the advances in time‐resolved fluorescence microscopy instrumentation. The interpretation of fluorescence polarization data in terms of dynamics and biological function of the macromolecular complexes in these physiological environments requires a deep understanding of the tracer rotational diffusion in such complex media. In this work we have studied the rotational diffusion of a tracer protein, apomyoglobin labeled with 1‐anilino‐8‐naphthalene sulfonate, in crowded solutions of an unrelated protein, ribonuclease A. We have evaluated the deviation of the different tracer rotational motions from the Stokes–Einstein–Debye diffusion behavior, and its relation to the properties of the transient molecular cavities where the tracer is rotating in the fluorescence lifetime window. Finally, we have analyzed the application of fluorescence polarization methods to determine the apparent equilibrium constants of homo and heteroassociations of macromolecules in crowded conditions. Copyright © 2004 John Wiley & Sons, Ltd.
Aggregation and surface‐enhanced Raman activity study of dye‐coated mixed silver–gold colloids
Authors: Fang Jinghuai , Huang Yunxia , Li Xia , Dou Xiaoming
Published: August 2004

The aggregate morphologies of silver, gold, and mixed silver–gold nanoparticles coated with fuchsine basic were directly investigated by means of transmission electron microscopy. It was found that the aggregation of silver and gold colloids induced by the adsorption of fuchsine basic displayed different aggregate characteristics. The adsorption of fuchsine basic in mixed silver and gold colloidal systems led to altered aggregation and surface‐enhanced Raman scattering (SERS) enhancement behavior. A suitable ratio of mixed silver and gold colloids could form a favorable state of aggregation and significantly increase the SERS activity of mixed colloids compared with single silver and gold colloids. This is the first report of the SERS of fuchsine basic on mixed silver and gold colloids. Copyright © 2004 John Wiley & Sons, Ltd.
Vibrational analysis, conformational stability, force constants, barriers to internal rotations, RHF, MP2 and DFT calculations of trans,trans‐2,4‐hexadiene
Authors: Mohamed Tarek A. , Abo Aly Mohamed M.
Published: August 2004

Six conformers are proposed for the trans,trans‐2,4‐hexadiene (TTHD) molecule. Utilizing the 6–31G(d) and 6–311 + G(d) basis sets at the levels of RHF, MP2 with full electron correlation and DFT‐B3LYP, five conformers are found to be transition states, due to the calculated imaginary wavenumber(s). Accordingly, the totally symmetric TTT conformer where the two methyl groups are staggered to all trans vinylic hydrogen's (C2h symmetry) is the stable conformer in the gaseous, liquid and crystalline phases. Aided by MP2(full)/6–311 + G(d) geometric parameters, a chosen value of the kinetic parameter F = 6.11284856 was determined. Utilizing the observed band at 148 cm−1 in the far‐infrared spectrum of the gas, a value of 1.41 ± 0.06 kcal mol−1 was obtained for the C3v internal rotor (V3), compared with 1.83 ± 0.07 kcal mol−1 predicted from a potential energy surface scan (1 kcal = 4.184 kJ). Aided by normal coordinate analysis and quantum chemistry (QC) calculations, the scaled quantum mechanical (SQM) force field was obtained employing five scaling factors for different types of vibrational motions. The scaled vibrational wavenumbers from both MP2(full) and B3LYP levels using the 6–31G(d) basis set provides an excellent approach to the observed fundamentals in either infrared or Raman spectra of the TTT conformer. Thus, confident vibrational assignments and potential energy distributions (PEDs) were provided for all fundamental modes of the TTT conformer. Moreover, the conformational stabilities, structural parameters, rotational constants, infrared intensities and Raman scattering activities are also reported. These results are discussed and compared with the experimentally determined values for some related conjugate systems when appropriate. Copyright © 2004 John Wiley & Sons, Ltd.
Raman spectroscopic evaluation of polyacrylonitrile‐based carbon nanofibers prepared by electrospinning
Authors: Kim Chan , Park Sang‐Hee , Cho Jang‐Ik , Lee Do‐Young , Park Tae‐Jin , Lee Wan‐Jin , Yang Kap‐Seung
Published: August 2004

Poly(acrylonitrile) (PAN) solutions in N,N‐dimethylformamide were electrospun into webs consisting of 350 nm ultra‐fine fibers. The webs were oxidatively stabilized and followed by heat treatment in the range of 700–1000°C. Characterization of the microstructure of PAN‐based carbon nanofibers was performed by x‐ray diffraction, field‐emission scanning electron microscopy, electrical conductivity and Raman spectroscopy. The Lc(002) and La(10) values were calculated to be 1.85–2.15 and 2.23–3.36 nm, respectively. The Lc(002) and La(10) values increased by about 86% and 66%, respectively, when the heat treatment temperature (HTT) was increased from 700 to 1000°C. The electrical conductivity of carbonized PAN nanofiber webs increased with increasing carbonization temperature, being 6.8 × 10−3 and 1.96 S cm−1 at 700 and 1000°C, respectively. The D and G bands from Raman scattering were fitted into a Gaussian–Lorentzian hybridized function, and the crystallite sizes in the nanofibers were evaluated from the R‐values determined from the ratios of the intensity of the G band to that of the D band. The domain size of the graphitic layers was in the range 1.6–3.2 nm with higher values at higher HTT. Copyright © 2004 John Wiley & Sons, Ltd.
Novel Fibers Prepared from Cellulose in NaOH/Urea Aqueous Solution
Authors: Cai Jie , Zhang Lina , Zhou Jinping , Li Hao , Chen Hui , Jin Huiming
Published: August 2004

Summary: Novel regenerated cellulose fibers have been successfully spun from the cellulose dope in NaOH/urea aqueous solution, which could rapidly dissolve cellulose. The fibers possess circular cross‐sections as well as relatively high molecular weight, and a crystallinity index with cellulose II family crystal structure, leading to good mechanical properties. This technology is simple, cheap, and environmentally friendly, promising to substitute for viscose rayon production having hazardous byproducts.

SEM micrograph of the cross‐section of the novel cellulose fibers generated here.

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SEM micrograph of the cross‐section of the novel cellulose fibers generated here.
Synthesis of Polystyrene and Polystyrene/Poly(methyl methacrylate) Nanoparticles
Authors: He Guangwei , Pan Qinmin
Published: August 2004

Summary: Polystyrene nanosize particles have been synthesized by a differential microemulsion polymerization process involving the use of a small amount of poly(methyl methacrylate) as the seeds. Sodium dodecyl sulfate and ammonium persulfate were used as the surfactant and initiator, respectively. The effects of various reaction conditions on the particle size have been investigated. Particle sizes of less than 20 nm have been achieved at milder conditions than those previously reported in the literature.

An HRTEM image of PS/PMMA nanoparticles.

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An HRTEM image of PS/PMMA nanoparticles.
Mathematical Modeling of the Bulk Photopolymerization of Furfuryl Acrylate
Authors: Lange Jurgen , Davidenko Natalia , Rieumont Jacques , Sastre Roberto
Published: August 2004

Summary: Experimental data for the photopolymerization of furfuryl acrylate (FA) conformed satisfactorily to the kinetics model proposed for the photopolymerization of furfuryl methacrylate (FM). This model allowed the kinetic constants of the basic steps of the studied mechanism, namely propagation, degradative transfer, re‐initiation and cross‐termination, to be determined. The calculated values of these constants were in agreement with the chemical nature of FA. For each of these constants, the confidence intervals were determined, and the statistical dependence between some of them was analyzed using the ellipse error method. The equations of moments of the distribution of molecular sizes of the primary chains in the network with order greater than one were developed to describe different molecular averages, such as weight‐average chain length and size‐average heterogeneity of the primary chains. The results found for the monomer conversion, the cross‐link degree and number‐average length of the primary chains of the network for FA were compared with those obtained for FM, and it was shown that the process of polymerization of the former monomer was more retarded and produced gels with a greater degree of cross‐linking than the latter as expected.

Network structures with different heterogeneity in size of the primary chains.

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Network structures with different heterogeneity in size of the primary chains.
Clinical and neuropsychological correlates in two brothers with pantothenate kinase–associated neurodegeneration
Authors: Marelli Cecilia , Piacentini Sylvie , Garavaglia Barbara , Girotti Floriano , Albanese Alberto
Published: August 2004

Adult‐onset focal dystonia was the presenting sign of pantothenate kinase‐associated neurodegeneration (PKAN) in a patient with a novel homozygous missense mutation (C856T). His brother shared the same mutation and showed similar, albeit minor, motor signs, but a different behavioral profile. Both brothers had an atypical form of PKAN. The neuropsychological assessment showed that, despite a normal Mini‐Mental State Examination, both patients presented a deficit of executive functions and of attention. The profile of cognitive impairment in these cases was typically that of a subcortical dementia. Both patients fulfilled Diagnostic and Statistical Manual for Mental Disorders criteria for obsessive–compulsive disorder; however, paranoia was associated with depression and aggressive behavior in Patient 1, whereas Patient 2 had hyperactivity, disinhibition, and euphoria. Our findings suggest that these two brothers had a different pattern of involvement of motor and nonmotor basal ganglia–thalamocortical circuits. © 2004 Movement Disorder Society
Expanded paper towel test: An objective test of urine loss for stress incontinence
Authors: Neumann Patricia , Blizzard Leigh , Grimmer Karen , Grant Ruth
Published: August 2004

Aim

To investigate the repeatability of a short stress test of coughing and jumping (the expanded Paper Towel Test (PTT)) to quantify urine loss in stress incontinent adult women.

Materials and Methods

In the laboratory, the reliability of two methods of measuring the size of the wet area, produced by a typical volume of water titrated onto paper towel was investigated and some absorbency properties of the brand of towel used were quantified. Thirty one women performed a provocative coughing and jumping test on consecutive days using a “perineal pad” of paper towel. The repeatability coefficient was calculated.

Results

The provocative test was repeatable to within 2.8 ml of urine loss, but with the exclusion of one anomalous result, the repeatability improved to lie within 1 ml. The coefficient of variation (CV) for the between‐method differences (computer scanning and graph paper) was 1.27%. A volume of 1 ml of water produced a wet area of 25.7 cm2. The range of measurable areas corresponded to volumes of 0.005–8 ml. Standardization of method is required because the size of the wet area differed by manufacturer of paper towel (P < 0.01, two products compared) and with time elapsed since titration (P < 0.01).

Conclusions

The “expanded PTT” is a simple tool for quantification of urine loss (0.005–8 ml) in women to 72 years with stress incontinence. With a suggested modification, it should prove reliable for detection of between‐visit differences of 1 ml. The reliability of the test is dependent upon the use of standard protocol and paper towel with known volume–area ratio. To improve clinical diagnosis, it can also be used with any brand of paper towel to confirm the sign of stress incontinence on exertion. © 2004 Wiley‐Liss, Inc.
A modified finite difference sensitivity analysis method allowing remeshing in large strain path‐dependent problems
Authors: Muñoz‐Rojas Pablo A. , Fonseca Jun S. O. , Creus Guillermo J.
Published: August 2004

Finite difference sensitivity analysis is simple and general yet usually inefficient and inaccurate compared to the analytical sensitivity approach. Although its high computational cost is not an issue in iteratively solved problems, its inaccuracies are critical in path‐dependent problems when remeshing is required. In this case, the errors caused by parametric inversion and interpolation in variables transfer to the new mesh can be as large as the gradient components. This paper presents an efficient modified finite difference approach that allows remeshing either in path‐independent or path‐dependent problems, not being affected by the aforementioned errors. The strategy to cope with remeshing is extensive to the semi‐analytical method which, for non‐linear analyses, is shown to be a particular case of the proposed finite difference sensitivity approach. With this implementation, the finite difference, the semi‐analytical and the analytical sensitivity methods all have comparable computational costs. The perturbation of unstructured meshes is performed with an inverse power Laplacian smoothing. The low cost and the accuracy of the sensitivity fields obtained after remeshing are shown in two examples, considering shape and constitutive design variables. Copyright © 2004 John Wiley & Sons, Ltd.
The disparate labor market impacts of monetary policy
Authors: Carpenter Seth B. , Rodgers III William M.
Published: August 2004

Employing two widely used approaches to identify the effects of monetary policy, this paper explores the differential impact of policy on the labor market outcomes of teenagers, minorities, out‐of‐school youth, and less‐skilled individuals. Evidence from recursive vector autoregressions and autoregressive distributed lag models that use information on the Federal Reserve's contractionary initiatives indicate that the employment‐population ratio of minorities is more sensitive to contractionary monetary policy than that of whites. The ratio falls primarily because of an increase in unemployment and not because of a decline in labor force participation. Monetary policy appears to have a disproportionate effect on the unemployment rate of teenagers, particularly African American teenagers. Their employment‐population ratios fall because of increased difficulty in obtaining employment. The larger responses are not caused by their higher likelihood of having been employed in industries and occupations that are more sensitive to contractionary monetary policy. © 2004 by the Association for Public Policy Analysis and Management.
The impact of the master settlement agreement on cigarette consumption
Authors: Sloan Frank A. , Trogdon Justin G.
Published: August 2004

In 1998, 46 states and the four major tobacco companies signed the Master Settlement Agreement (MSA), which stipulated that the tobacco companies pay states $206 billion over 25 years and take steps to reduce youth smoking. The remaining states settled separately. We sought to determine the effect of the settlements on demand for cigarettes. Using a nationwide sample from 1990 to 2002, we estimated a model of the decision to smoke cigarettes. The settlements affected smoking primarily through price increases for cigarettes, although there was evidence that other policy instruments influenced smoking rates for younger smokers. By 2002, the settlements had reduced overall smoking rates by 13 percent for ages 18 to 20 and older than 65 and 5 percent for ages 21 to 64. © 2004 by the Association for Public Policy Analysis and Management.
Federal policy mandating safer cigarettes: A hypothetical simulation of the anticipated population health gains or losses
Authors: Tengs Tammy O. , Ahmad Sajjad , Moore Rebecca , Gage Eric
Published: August 2004

If manufacturing a safer cigarette is technically possible—an open question—then mandating that tobacco manufacturers improve the safety of cigarettes would likely have both positive and negative implications for the nation's health. On the one hand, removing toxins may reduce the incidence of smoking‐related diseases and premature mortality in smokers. On the other hand, smokers might be less inclined to quit, those who have quit might resume the habit, and youth who have never smoked will have one less reason to avoid tobacco use. To assess the expected population health impacts of a legislative or regulatory mandate, we created the Tobacco Policy Model, a system dynamics computer simulation model. The model relies on secondary data and simulates the U.S. population over time spans as long as 50 years. Our simulation results reveal that even if requiring cigarettes to be safer makes smoking more attractive and increases tobacco use, a net gain in population health is still possible. © 2004 by the Association for Public Policy Analysis and Management.
Controlled release of indole‐3‐butyric acid (IBA)—based on polymeric matrix prepared by ionizing radiation
Authors: El‐Rehim H. A. Abd , Hegazy El‐Sayed. A. , El‐Mohdy H. L. Abd
Published: August 2004

Polyacrylamide/polyethylene oxide (PAAm/PEO) controlled release matrices were designed to obtain a better control over the concentration of indole‐3‐butyric acid (IBA). PAAm/PEO incorporated IBA was prepared by exposing aqueous solutions of PEO, PAAm, crosslinking agent N,N′‐methylene‐bisacrylamide, and IBA mixtures to electron beam irradiation. PAAm/PEO copolymer structural property relationships that affect its controlled release behavior were determined. Analysis of the results obtained indicated that it is possible to optimize IBA controlled release by adjusting the dimensions and crosslinking degree of the copolymer as well as the concentration of the incorporated IBA. The crosslinking degree of the copolymer can be controlled by governing the irradiation dose, polymer blend composition and/or the amount of crosslinking agent. IBA release rates have been investigated as a function of environmental conditions, such as the changes in pH and temperature to determine the factors, which mostly contribute to the release of IBA. The effect of PAAm/PEO–IBA matrix on the average height of corn (Zea mayz) plant was investigated. The results obtained, revealed that PAAm/PEO‐IBA systems have a capability to deliver IBA slowly and continuously. As a result, the development of root and vegetative systems of Zea mayz plant was greatly promoted. Copyright © 2004 John Wiley & Sons, Ltd.