bluuebunny/crossref_metadata_2025_split huggingface dataset:
Image reconstruction with a shift‐variant filtration in circular cone‐beam CT
Authors: Yu Lifeng , Pan Xiaochuan , Pelizzari Charles A. 
Published: March 2005

AbstractIt is well known that cone‐beam data acquired with a circular orbit are insufficient for exact image reconstruction. Despite this, because a cone‐beam scanning configuration with a circular orbit is easy to implement in practice, it has been widely employed for data acquisition in, e.g., micro‐CT and CT imaging in radiation therapy. The algorithm developed by Feldkamp, Davis, and Kress (FDK) and its modifications, such as the Tent–FDK (T‐FDK) algorithm, have been used for image reconstruction from circular cone‐beam data. In this work, we present an algorithm with spatially shift‐variant filtration for image reconstruction in circular cone‐beam CT. We performed computer‐simulation studies to compare the proposed and existing algorithms. Numerical results in these studies demonstrated that the proposed algorithm has resolution properties comparable to, and noise properties better than, the FDK algorithm. As compared to the T‐FDK algorithm, our proposed algorithm reconstructs images with an improved in‐plane spatial resolution. © 2005 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 14, 213–221, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.20026
Temperature‐dependent feature sensitivity analysis for combustion modeling
Authors: Zhao Zhenwei , Li Juan , Kazakov Andrei , Dryer Frederick L. 
Published: March 2005

AbstractSensitivity analysis is one of the most widely used tools in kinetic modeling. Typically, it is performed by perturbing the A‐factors of the individual reaction rate coefficients and monitoring the effect of these perturbations on the observables of interest. However, the sensitivity coefficients obtained in this manner do not contain direct information on possible temperature‐dependent effects. Yet, in many combustion processes, especially in premixed flames, the system undergoes substantial temperature changes, and the relative importance of individual reaction rates may vary significantly within the flame. An extension of conventional sensitivity analysis developed in the present work provides the means of identifying the temperatures at which individual reaction rate coefficients are most important as a function of input parameters and specific experimental conditions. The obtained information is demonstrated to be of critical relevance in optimizing complex reaction schemes against multiple experimental targets. Applications of the presented approach are not limited to sensitivities with respect to reaction rate coefficients; the method can be used for any temperature‐dependent property of interest (such as binary diffusion coefficients). This application is also demonstrated in this paper. © 2005 Wiley Periodicals, Inc. Int J Chem Kinet 37: 282–295, 2005
Microscopic features of methacrylate polymers with zwitterionic pendant groups determined by various techniques
Authors: Cardoso J. , Montiel Raúl , Huanosta‐Tera Alfonso 
Published: March 2005

AbstractThe objective of this work was to determine microscopic structural features of three methacrylate polymers with different numbers of diethylene glycol residues and zwitterionic pendant groups. X‐ray diffraction, electron microscopy, and scanning probe microscopy techniques were employed. X‐ray data led to the adoption of a model made up of molecular aggregates forming lamellar domains, establishing in this way ordered characteristics of these kinds of polymers. Scanning electron microscopy images provided evidence of the occurrence of a lamellar structure forming the morphology of the polymers. This was corroborated by atomic force microscopy experiments. Transmission electron microscopy revealed that the lamellar aggregates conformed into clusters immersed in a polymeric matrix. From phase‐contrast images, information on the homogeneity of the composition at a molecular surface level was obtained. Then, the techniques provided evidence of the lamellar domain characteristics of the studied sulfobetaines. The crystallinity was a function of the number of ethoxy groups because as this number increased, the crystallinity became lower © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1152–1160, 2005
Non‐destructive, room temperature characterization of wafer‐sized III–V semiconductor device structures using contactless electromodulation and wavelength‐modulated surface photovoltage spectroscopy
Authors: Huang Y. S. , Pollak F. H. 
Published: March 2005

AbstractWe review the use of the contactless methods of photoreflectance (PR), contactless electroreflectance (CER) and wavelength modulated differential surface photovoltage spectroscopy (DSPS) for the nondestructive, room temperature characterization of a wide variety of wafer‐scale III–V semiconductor device structures. Some systems that will be discussed include heterojunction bipolar transistors (including the determination of the built‐in fields/doping levels in the emitter and collector regions, alloy composition, and dc current gain factor), pseudomorphic GaAlAs/InGaAs/GaAs high electron mobility transistors (including the determination of the composition, width, and two‐dimensional electron gas density in the channel), InGaAsP/InP quantum well edge emitting lasers (including the detection of p‐dopant interdiffusion), vertical‐cavity surface‐emitting lasers (determination of fundamental conduction to heavy‐hole excitonic transition and cavity mode). (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Intravenous Ketoprofen in Postoperative Pain Treatment after Major Abdominal Surgery
Authors: Oberhofer Dagmar , Skok Jasna , Nesek‐Adam Visnja 
Published: March 2005

AbstractIn recent years considerable attention has been paid to the treatment of postoperative pain, with regard to the favorable effect of adequate analgesia on patient outcome. Multimodal analgesia (e.g., opioids and nonsteroidal anti‐inflammatory drugs [NSAIDs] or local anesthetics) is recommended for effective postoperative pain relief. There are few data on the use of NSAIDs in postoperative pain treatment after abdominal surgery. We conducted a randomized, double‐blind, placebo‐controlled study to assess the analgesic efficacy and safety of ketoprofen after major abdominal surgery. One and nine hours postoperatively patients received 100 mg of ketoprofen i.v. (n = 21) or placebo (n = 22) in addition to a pain‐treatment protocol consisting of continuous infusion of tramadol 200 mg and metamizol 5 g over 24 hours with additional 25 mg i.v. tramadol in case of inadequate analgesia. Pain was assessed by numeric rating scale at rest and at deep breath 3, 6, 12, and 24 hours postoperatively and the total dose of tramadol used in the first 24 hours was recorded. Patients in the ketoprofen group had significantly lower pain scores both at rest and at deep breath, at 3 (p < 0.01), 6, and 12 hours (p < 0.05) postoperatively. The 24‐hour use of tramadol was significantly lower in the ketoprofen group (p < 0.01), with less nausea and vomiting. There were no bleeding complications or other adverse events related to ketoprofen therapy. The study showed the value of short‐term use of ketoprofen to improve the quality of analgesia after major abdominal surgery without significant adverse effects.
The Significance of Meckel’s Diverticulum in Appendicitis — A Retrospective Analysis of 233 Cases
Authors: Ueberrueck Torsten , Meyer Lutz , Koch Andreas , Hinkel Michael , Kube Rainer , Gastinger Ingo 
Published: March 2005

AbstractConflicting reports are found in the literature concerning whether to remove an incidentally discovered Meckel’s diverticulum (MD). Between 1.1.1974 and 31.12.2000, at a single center, the perioperative data associated with appendectomy (AE) were recorded consecutively and analyzed retrospectively. All patients in whom an MD was discovered during an AE were included in the study. The clinical presentation, postoperative course, and follow‐up in all MDs left in place were analyzed. During the course of 7927 AE, 233 MD (2.9%) were detected. Of these 80.7% (n = 188) were removed and 19.3% (n = 45) were left untouched. In 9% (n = 21) of all detected diverticula pathological changes were found. Ectopic tissue was seen in 12.2% (n = 23) of the MDs removed. The postoperative complication rates did not differ significantly between patients in whom the MD was removed (9.5%; n = l8) and those in whom it was not (17.7%; n = 8); in the latter group the appendicitis was of the more acute type (gangrenous or perforated) (24.4% vs. 4.3%). In 18 patients (40.0%) with non‐removed MDs, a follow‐up period of 14.1 ± 5.8 years was achieved. Complications associated with a non‐removed MD were not observed. If during the course of an AE a MD is detected, the present data, as well as those in the literature, suggest that an individualized approach should be taken. Meckel’s diverticulum with obvious pathology should always be removed. In cases of gangrenous or perforated appendicitis, an incidentally discovered MD should be left in place, whereas in an only mildly inflamed appendix it should be removed.
Effect of Volatile Anesthetics on Oxidative Stress Due to Occupational Exposure
Authors: Türkan Hülya , Aydin Ahmet , Sayal Ahmet 
Published: March 2005

AbstractPossible health hazards from long‐term exposure to inhalation anesthetics cannot yet be definitively excluded. One of the adverse effects of general anesthetics is the exogen sources of reactive oxygen radicals that are responsible for several diseases. We designed the present study to determine the effect of volatile anesthetics on oxidative stress due to occupational exposure. We enrolled 30 anesthesia and surgery personnel who had been exposed to inhalation anesthetics for 3 years and 30 healthy volunteer personnel who had not been exposed to inhalation anesthetics at any period of their life as the control group. Blood samples were taken from both groups for determination of superoxide dismutase, glutathione peroxidase, and their cofactors, which are selenium, copper, and zinc levels. Our results revealed that plasma and erythrocyte antioxidant activity and trace element levels were significantly lower in operating room personnel compared to that in the control groups. We concluded that the antioxidant defense system was affected by free radical injury in anesthesia and surgery personnel who had been exposed to inhalation anesthetics chronically. Therefore, minimizing occupational exposure to volatile anesthetics is important for protecting operation room personnel from hazards. Operating room personnel should also take antioxidant supplements.
Searching for Non‐RET Molecular Alterations in Medullary Thyroid Carcinoma: Expression Analysis by mRNA Differential Display
Authors: Musholt Thomas J. , Hanack Julia , Brehm Christoph , von Wasielewski Reinhard , Musholt Petra B. 
Published: March 2005

AbstractSome 25%–70% of sporadic medullary thyroid carcinomas (MTCs) are associated with somatic mutations within the RET proto‐oncogene. In a significant number of MTCs, however, no such genetic variations can be detected, which implies alternative pathogenic molecular alterations. To assess altered RET mutation–specific gene expression, and to identify yet unknown gene transcripts involved in the tumorigenesis of MTC, we performed an expression analysis by mRNA differential display (RT‐DD). Snap‐frozen tumor tissues and corresponding normal thyroid tissues of 8 patients suffering from MTC (6 sporadic, 2 hereditary tumors) were included in the study; 5/8 MTCs harbored RET point mutations (codons 618, 634, 918). The RT‐DD method was refined by use of fluorescence‐labeled arbitrary oligonucleotides, electrophoresis on an automated sequencer, and a novel fragment‐recovery technique utilizing a high‐performance fluorescence scanner. More than 400 differentially expressed mRNA transcripts—representing upregulated or downregulated genes in the compared tissues—were detected. In all, 28 selected fragments were recovered, cloned, sequenced, and identified. Differential expression of gene transcripts with known association to cell proliferation or tumor progression—such as annexin A2, Rab11a, trefoil proteins, superoxide dismutase (SOD1), mitochondrial displacement loop (D‐loop), and G protein subunit gamma11—as well as of the neuroendocrine marker chromogranin was observed. Furthermore, several mRNA transcripts of yet unknown genes displayed mutation‐specific upregulation or downregulation in MTC. Illumination of the molecular basis especially of C‐cell carcinomas without detectable alterations of the RET receptor tyrosine kinase will be required for the development of therapeutic strategies for advanced tumors that cannot be bridled or cured by surgical interventions alone.
Differentiation in the ability to utilize Pterostyrax hispida (Ebenales: Styracaceae) among four local populations of the phytophagous ladybird beetle Henosepilachna yasutomii (Coleoptera: Coccinellidae)
Authors: Fujiyama Naoyuki , Matsumoto Kazuma , Kobayashi Norio , Ohta Yuri , Katakura Haruo 
Published: March 2005

AbstractThe oligophagous ladybird beetle Henosepilachna yasutomii Katakura (Coleoptera: Coccinellidae) shows inter‐population differences in its host‐use. In this beetle, populations using the deciduous tree Pterostyrax hispida Sieb. et Zucc. (Styracaceae) were recently rediscovered in the Kanto districts of central Honshu, Japan. In the present study, the ability to utilize P. hispida and other host plants was compared among four populations of H. yasutomii occurring on P. hispida and Scopolia japonica Maxim. (Solanaceae), Chelidonium japonicum Thunb. (Papaveraceae), and Solanum tuberosum L. (Solanaceae). As regards the feeding habits of adult beetles, only the populations occurring on P. hispida accepted this plant's leaves, which differed distinctly from the feeding habits of the other populations, although the differences among the four populations were not readily apparent with respect to the leaf amounts consumed. The larvae from the populations occurring on P. hispida showed significantly higher survivorship on this plant than did the larvae from the other populations. Considering the host use patterns and the life cycles of beetles under natural conditions, the large abundance of P. hispida leaves throughout the season may have played an important role in selection for the ability to utilize P. hispida observed in the H. yasutomii populations occurring on this woody host.
Dynamics of methane in mesotrophic Lake Biwa, Japan
Authors: Murase Jun , Sakai Yuji , Kametani Aya , Sugimoto Atsuko 
Published: March 2005

AbstractAs a part of a core project of IGBP (International Geosphere‐Biosphere Programme), distribution, production, oxidation and transport processes of methane in bottom sediments and lake water in a mesotrophic lake (Lake Biwa) have been studied with special reference to the spatial heterogeneity of each process. In this study, we attempted to synthesize previously reported results with newly obtained ones to depict the methane dynamics in the entire lake. The pelagic water column exhibited subsurface maxima of dissolved methane during a stratified period. Transect observation at the littoral zone suggested that horizontal transportation may be a reason for the high methane concentration in epilimnion and thermocline at the offshore area. Tributary rivers and littoral sediments were suggested to be the source. Observations also showed that the internal wave caused resuspension of the bottom sediment and release of methane from the sediment into the lake water. The impact of the internal waves was pronounced in the late stage of a stratified period. The littoral sediment showed much higher methanogenic activity than the profundal sediments, and the bottom water of the littoral sediments had little methanotrophic activity. In the profundal sediment, most of the methane that diffused up from the deeper part was oxidized when it passed through the oxic layer. Active methane oxidation was also observed in the hypolimnetic water, while the lake water in the epilimnion and thermocline showed very low methane oxidation, probably due to the inhibitory effect of light. These results mean a longer residence time for methane in the epilimnion than in the hypolimnion. Horizontal inflow of dissolved methane from the river and/or littoral sediment, together with the longer residence time in the surface water, may cause the subsurface maxima, which have also been observed in other lakes and in the ocean.
Seed germination of high mountain Mediterranean species: altitudinal, interpopulation and interannual variability
Authors: Giménez‐Benavides L. , Escudero A. , Pérez‐García F. 
Published: March 2005

AbstractThe germination response of 20 species from high altitude Mediterranean climates, most of them rare endemics, was studied. Our main goal was to model the germination response of a complete set of Iberian high mountain species. The effect of temperature and other parameters, such as spatial and temporal short gradients, on germination were also evaluated. Some seed features (mass and size) were also related to the germination response. Finally, we tested the effect of cold‐wet stratification pretreatment when germination was low under natural conditions. Seeds were collected at four locations from 1,900 to 2,400 m a.s.l. in the Sierra de Guadarrama (Spanish Central Range) over two consecutive growing seasons (2001–2002) and submitted to different temperatures and a constant photoperiod of 16 h light/8 h darkness. Most plants readily germinate without treatment, reaching an optimum at relatively high temperatures in contrast to lowland Mediterranean species. Seeds seem to be physiologically prepared for rapid germination even though these plants usually face very intense summer droughts after ripening and dispersal. Germination was also highly variable among altitudes, populations and years, but results were inconsistent among species. Such flexibility could be interpreted as an efficient survival strategy for species growing under unpredictable environments, such as the Mediterranean climate. Finally cold‐wet stratification increased germination capacity in five of nine dormant species, as widely reported for many arctic, boreal and alpine species. In conclusion, high mountain Mediterranean species do not differ from alpine species except that a relatively high number of species are ready to germinate without any treatment.
Effect of Permeate Flux Rate on Alkaloid Production in a Novel Plant Cell Membrane Reactor Using Coffea arabica Cells
Authors: Lang Jeffrey A. , Yoon Kwang‐Hun , Prenosil Jiri E. 
Published: March 2005

AbstractA novel membrane reactor was developed for phytochemical production using plant cells. The membrane reactor was a flat plate construction. An autoclavable, polypropylene membrane sheet with pore size 0.075 μm. was used. The membrane was surfactant treated by the manufacturer. Medium was recirculated through medium channels under the membrane. Cells were supplied with nutrients by permeated medium and obtained oxygen from the surrounding gas phase. In this work, the effect of permeate flux rate on cell growth, glucose uptake, and alkaloid production was examined. An arbitrary pressure index scale was developed to regulate the amount of medium that permeated the membrane. It was based on differential pressures between the cell chamber and the medium recirculation loop. These pressures were measured at the medium inflow and outflow points to the membrane reactor. Three 21‐day batch runs were carried out with the membrane reactor at pressure indices 38, 53, and 68 and compared to parallel shake‐flask runs. The pressure index 53 run was determined to be optimum for cell growth and purine alkaloid formation. Cell mass increase in the membrane reactor was 3.2‐fold and in parallel suspension cultures was 3.3‐fold, approximately 1.5 times that of the other two reactor runs. Glucose decreased linearly in the pressure index 53 membrane reactor run to 7.7 g/L, while glucose was completely consumed in the suspension cultures after 12 days. Final alkaloid concentration was 46.1 mg/L for the pressure index 53 membrane reactor run, approximately 2 times that of the other two membrane reactor runs and the suspension cultures.
Modification of Enzyme Activity in Reversed Micelles through Clathrate Hydrate Formation
Authors: Rao A. Madhusudhan , Nguyen Huyen , Johnn Vijay T. 
Published: March 2005

AbstractThe physical phenomenon of clathrate hydrate formation in protein‐containing reversed micelles is described. Hydrate formation in reversed micelles is a method of adjusting the water to surfactant molar ratio, wo, which influences micellar size. Lipase and α‐chymotrypsin encapsulated in large reversed micelles of high wo show significant enhancements in activity when the micelle size is reduced through hydrate formation. Alternate methods of micelle size adjustments also show enhancements in activity. The implications for improving the activity of such encapsulated enzymes recovered from fermentation media through phase transfer into reversed micelles are discussed.
Expression of Three Recombinant Proteins Using Baculovirus Vectors in 23 Insect Cell Lines
Authors: Hink W. F. , Thomsen D. R. , Davidson D. J. , Meyer A. L. , Castellino F. J. 
Published: March 2005

AbstractRecombinant Autographa California baculoviruses expressing genes for pseudorabies virus glycoprotein (gp50T), human plasminogen (HPg), and β‐galactosidase (β‐gal) were used to infect 23 cell lines or strains. The objectives were to compare amounts of recombinant proteins expressed in the cell lines, compare yields from clones and parent lines, investigate the effects of long‐term culture in serum‐free medium on production, and determine if some lines yield gp50T with different glycosylation patterns. For HPg, IZD‐MB0503 had the highest yield and four other lines (IPLB‐TN‐R2, IPLBSF‐1254, IPLB‐LdEIta, and CM‐1) had levels above that of SF‐9 cells. For gp50T, four lines (IPLB‐HvT1, IPLB‐SF21AE, IPLB‐SF21AE‐15, and IPLB‐SF‐1254) had higher amounts than SF‐9 cells. Some lines yielded gp50T with molecular mass about 1000 daltons larger than that from SF‐9 cells, which suggests increased oligosaccharide processing. Equally high levels of β‐gal were expressed in three lines (SF‐9, IZD‐MB0503, and BCIRL‐PX2‐HNV3). The major conclusion is that no single cell line produced highest yields for all three recombinant proteins. Four lines were cultured in serumfree medium for 31–34 passages and then infected with the three recombinant viruses. For most cell line‐recombinant combinations, the yields in serum‐free medium were equal to or better than those in serum‐supplemented medium. Medium composition had a much stronger effect on foreign gene expression than on susceptibility of cells to wild‐type virus.