bluuebunny/crossref_metadata_2025_split huggingface dataset:
Environmentally friendly policy schemes as models for the introduction and use of agri‐environmental indicators in Greece
Authors: Vlahos George , Beopoulos Nikos 
Published: October 2003

AbstractA considerable number of indicators are already in use for the assessment of the agricultural sector's environmental performance as well as for the evaluation of agri‐environmental policies.Given the existing difficulties in testing such indicators, we have used for this purpose – with fairly good results – the documentation (at the farm level) of two environmentally friendly policy schemes, on organic agriculture and on integrated management, for assessment of the set of agri‐environmental indicators, described in two relevant communications from the Commission.Indicators describing pressures and state of the environment susceptible to estimation differ significantly from one scheme to another. However, available documentation, if complemented, makes plausible an environmental diagnosis of farms as well as monitoring and evaluation of environmental performance of these schemes. Copyright © 2003 John Wiley & Sons, Ltd and ERP Environment.
Study of the Complexation, Adsorption and Electrode Reaction Mechanisms of Chromium(VI) and (III) with DTPA Under Adsorptive Stripping Voltammetric Conditions
Authors: Sander Sylvia , Navrátil Tomáš , Novotný Ladislav 
Published: October 2003

AbstractThe complexation of Cr(III) and Cr(VI) with diethylenetriaminepentaacetic acid (DTPA), the redox behavior of these complexes and their adsorption on the mercury electrode surface were investigated by a combination of electrochemical techniques and UV/vis spectroscopy. A homogenous two‐step reaction was observed when mixing Cr(III), present as hexaquo complex, with DTPA. The first reaction product, the electroactive 1 : 1 complex, turns into an electroinactive form in the second step. The results indicate that the second reaction product is presumably a 1 : 2 Cr(III)/DTPA complex. The electroreduction of the DTPA‐Cr(III) complex to Cr(II) was found to be diffusion rather than adsorption controlled.The Cr(III) ion, generated in‐situ from Cr(VI) at the mercury electrode at about −50 mV (vs. Ag|AgCl) (3 mol L−1KCl), was found to form instantly an electroactive and adsorbable complex with DTPA. By means of electrocapillary measurements its surface activity was shown to be 30 times higher than that of the complex built by homogenous reaction of DTPA with the hydrated Cr(III). Both components, DTPA and the in‐situ built complex Cr(III) ion were found to adsorb on the mercury electrode.The effect of nitrate, used as catalytic oxidant in the voltammetric determination method, on the complexation reaction and on the adsorption processes was found to be negligible.The proposed complex structures and an overall reaction scheme are shown.
Caffeine Extraction with a Karr Reciprocating Plate Column
Authors: Hu X. , Wang X. , Yang H. 
Published: October 2003

AbstractA Karr reciprocating plate column was used in extracting caffeine from the methylation mother solution of a caffeine synthesis plant with chloroform as the extractant. Pilot tests were carried out in a 38 mm diameter column to determine holdup, flooding and mass transfer at various reciprocation velocities. Results show that the holdup in the presence of mass transfer is higher than that in the absence of mass transfer, and the height of the equivalent theoretical stage (HETS) was 0.57 m for a 99.9 % recovery at the optimum reciprocation velocity. The Karr empirical correlation for scale‐up was used to predict the column height in the design of the industrial process. A 0.4 m and a 0.6 m diameter column were used to treat 2.5 m3/h and 6.0 m3/h methylation mother solution, and the corresponding HETSs were 1.42 m and 1.53 m for a 99.9 % recovery, respectively. The axial dispersion coefficients of the dispersed phase were estimated for the 0.4 m and the 0.6 m diameter columns. For a better recovery the ratio of the axial dispersion coefficient of the dispersed phase to that of the continuous phase was about 2.7–3.0.
Pretreatment and Hydrolysis of Brewer's Spent Grains
Authors: Macheiner D. , Adamitsch B.F. , Karner F. , Hampel W.A. 
Published: October 2003

AbstractBrewer's spent grains (BSG), the voluminous residue after mashing, contains on dry weight basis about 40–50 % polysaccharides. For the recovery of soluble carbohydrates from BSG different physical, thermal and enzymatic treatments were used to solubilize the polysaccharides in BSG. Heating by microwave radiation to 160 °C in the presence of 0.1 M HCl released 35 % of the material in the form of reducing sugar, indicating that about 80 % of the polysaccharides were hydrolyzed. Nevertheless, 0.1 M acetic acid will even solubilize 30 % of the material as oligosaccharides on a prolonged incubation when pretreating the spent grains by extrusion cooking. A combination of the enzymes Ceremix Plus MG and CelluPract AL 70 achieved an almost 25 % release of saccharides after 4 hrs of incubation at 50 °C. A combination of extrusion cooking and enzymatic hydrolysis seems to be a very promising procedure.
Constitution, microstructure, mechanical properties, and performance of magnetron‐sputtered carbon films with additions of silicon
Authors: Bauer C. , Leiste H. , Stüber M. , Ulrich S. , Holleck H. 
Published: October 2003

AbstractAmorphous carbon films with additions of silicon were deposited by non‐reactive magnetron sputtering on WC‐Co hard metal and on silicon substrates. The targets were hot‐pressed, homogenous mixtures of graphite and silicon carbide powder. Additional argon ion bombardment of the growing film was applied by a substrate bias varied between 0V and ‐800 V. The deposited amorphous carbon films with two different silicon contents (5 at.% and 23 at.% respectively) were characterised with respect to their microstructure, density, thickness, residual stress, Vickers hardness, Young's modulus, critical load of failure, friction coefficient, and wear behaviour. The residual stress of the carbon films could be remarkably lowered by silicon additions (23 at.%). The hardness reached high values (2200 HV0.05) and the friction coefficient for unlubricated sliding friction against a steel (1.3505) counterpart was as low as 0.06.
Leistungsfähige PVD‐Wälzlagerbeschichtungen
Authors: Gold P. W. , Loos J. , Kuhn M. 
Published: October 2003

AbstractAnhand von Axial‐Zylinderrollenlagern wurde systematisch untersucht, inwieweit PVD‐Schichten in der Lage sind, die Funktionen von EP/AW‐Schmierstoffadditiven zu übernehmen. Die Wälzlager wurden im starken Mischreibungsgebiet geprüft, um die Leistungsfähigkeit der Schichten möglichst schnell differenzieren zu können. Verschiedene Schichtsysteme wurden auf ihre Fähigkeit hin untersucht, einen unbeschichteten Gegenkörper zu schützen. Dazu wurden bei Wälzlagern lediglich die Lagerscheiben beschichtet, die Rollen blieben unbeschichtet. Dabei zeigten vier Me‐C:H‐Schichsysteme beste Verschleißschutzeigenschaften und kaum Oberflächenschädigungen. Der Übertrag von Schichtmaterial auf die unbeschichtete 100Cr6 Wälzkörperoberfläche konnte für den hervorragenden Verschleißschutz verantwortlich gemacht werden. Dazu wurden genauere Untersuchungen mit der ESMA Analyse (electron beam micro range analysis) bei ZrCg‐Schichten durchgeführt. Es konnte eine Triboschicht mit hohen Zirkon‐ und Sauerstoffanteilen nachgewiesen werden.
Metallurgical Aspects of Sliding Wear of fcc Materials for Medical Applications
Authors: Büscher R. , Fischer A. 
Published: October 2003

AbstractWorn surfaces of biomedical fcc alloys X2CrNiMo18‐15‐3, CoCr29Mo6, X13CrMnMoN18‐14‐3 are generated by sliding wear in order to understand the mechanisms, which bring about small wear particles. Depending on the acting wear mechanisms the debris is produced by different sites of crack initiation and paths of crack propagation. Thus, the subsurface deformation mechanisms are investigated as well. This investigation revealed that the worn surfaces of all three materials consist of a nanocrystalline layer underneath which appearances of cyclic deformation are visible. With respect to the stacking fault energy X13CrMnMoN18‐14‐3 as well as the CoCr29Mo6 depict sliding bands, stacking faults, and strain induced ε‐martensite bringing about a sufficient support of the nanocrystalline layer. Thus, 80 to 500 nm fine globular and lamellar wear particles are just torn off this layer. In contrast to this, X2CrNiMo18‐15‐3 shows cell walls in distances of about 50 μm below the worn surfaces, which act as sites for crack initiation and propagation. The mean wear particles are about an order of magnitude bigger and range from 20 to 250 μm. Due to the fact that the nanocrystalline layer is not supported by the material underneath it has no distinct positive effect on the wear rate.
Electromagnetic effects on the friction and wear of solid‐solid interface
Authors: Bhushan B. , Ge S. 
Published: October 2003

AbstractThis paper presents the state‐of‐the‐art of recent investigations on the friction and wear behavior of some solid interfaces in a magnetic field or electric current environment. The tribometers used for study of electromagnetic effect on friction and wear are introduced. The experimental results of the variation of coefficient of friction and wear rate for magnetic and nonmagnetic materials and materials with varying electrical conductivities are summarized. It is found that both magnetic field and electric current have significant influence on the friction and wear of these materials. The magnetic and electrical properties of sliding couples control the friction and wear in response to applied magnetic field and electric current, respectively. Relevant mechanisms and observations are also reported in the paper.
Tribology of Ceramics and Hard Coatings
Authors: Kato K. 
Published: October 2003

AbstractBecause of the high hardness of ceramics and ceramic coatings, very smooth wear surfaces are generated in the run‐in process under certain frictional conditions. In vacuum, tribo‐assisted In coating gives friction coefficient in the range from 0.10 to 0.02 between Si3N4 pins and SUS440C steel disks. In water, friction coefficient in the range from 0.01 to 0.001 is generated between self‐mated Si3N4 and SiC in sliding. In N2 gas, friction coefficient in the range from 0.01 to 0.001 is generated between Si3N4 ball and CNx coating and between DLC coated ball and DLC coated disk. These low friction coefficients observed with ceramics and without oil are promising new tribo‐technologies for space and environment.
Microsurgical tracheotomy: A pediatric model in growing rats
Authors: Cecília Bochetti Manna Mônica , Frasson de Souza Montero Edna , Quintino de souza Leão Jovelino , Ferreira Novo Neil 
Published: October 2003

AbstractPrevious studies described controversial opinions about pediatric tracheotomy concerning type of tracheal incision and long‐term results, which remain as important research subjects. Experimental studies on rat tracheas are scarce, probably because of technical difficulties related to the structures' small dimensions. As many rat organ and system operative procedures were studied successfully by using microsurgical techniques, we decided to develop a pediatric tracheotomy model in growing rats which would permit long‐term studies. Forty‐four Wistar EPM‐1 growing rats weighing 86 g and aged 35 days were divided into three groups: submitted to longitudinal, transverse, and segment excision of the trachea. Under sterile technique and intramuscular anesthesia (ketamine/xylazine), the trachea was exposed and incised, according to group, and a hand‐made endotracheal cannula was inserted into the organ. This cannula was assembled using a segment of 1.5‐cm‐long 3 French silicone catheter passed through hexagonal‐shaped silicone screen. The tracheal cannula was removed after 7 days, when we evaluated body weight, secretions, and dehiscence. In conclusion, this microsurgical tracheotomy model in growing rats is feasible, allowing studies on long‐term repercussions of pediatric tracheotomy. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:530–534 2003
Morphological changes on small‐bowel fetal allografts in mice
Authors: Resende Vanessa Contato Lopes , Montero Edna Frasson De Souza , Leão Jovelino Quintino De Souza , Manna Mônica Cecília Bochetti , Koike Márcia Kiyomi , Pedrosa Marcelo Eduardo , Simões Manuel De Jesus 
Published: October 2003

AbstractThe aim of this study was to evaluate the early morphological development and acute rejection process in fetal intestine allografts. Grafts from C57BL/6 fetal intestines were implanted in an avascular form in BALB/C recipients. A syngeneic group of animals was used to compare the evolution. The allogeneic recipients were distributed in 6 groups, according to the day of sacrifice (3rd, 4th, 5th, 6th, 7th, and 10th postoperational day (POD)) and the control group on the 2nd, 5th, and 7th POD. These grafts were stained with hematoxylin and eosin for histological evaluation, in agreement with the classification of Auber et al. (Chirurgie 123:122–130, 1998). Data showed a progressive development of the graft until POD 5. On POD 3 and 4, a top grade of development and an initial rejection were observed. From POD 5–7 and on POD 10, the acute rejection reaction was more important than the development process. The higher level of rejection was observed on POD 10, and it was similar to the 7th POD. Our results showed good graft development until POD 5. After that, the acute rejection response impeded analysis of the development process.O objetivo deste trabalho foi avaliar o desenvolvimento e o processo de rejeição aguda em aloenxertos de intestino fetal. Enxertos de intestino fetal de camundongos C57BL foram implantados de forma avascular. Os receptores foram distribuídos em 6 grupos, de acordo com o dia do sacrifício (3°, 4°, 5°, 6°, 7°, e 10°). Um grupo singênico foi feito para comparar a evolução. Os receptores alogênicos foram distribuídos em 6 grupos, de acordo com o dia do sacrifício (3°, 4°, 5°, 6°, 7°, e 10° PO) e o grupo controle foi separado em dias críticos para comparar a evolução: 2°, 5°, e 7° PO. Estes enxertos foram corados com hematoxilina e eosina para avaliação histológica, de acordo com a classificação de Auber et al. (Chirurgie 123:122–130, 1998). Os dados mostraram um desenvolvimento progressivo dos enxertos até o 5° PO. Observou‐se que no 3° e no 4° PO ocorreu um bom grau de desenvolvimento e um estágio inicial de rejeição. Do 5° ao 7° PO e no 10° PO, a reação de rejeição aguda foi mais importante do que o processo de desenvolvimento. O mais alto nível de rejeição foi observado no 10° PO, que foi semelhante ao do 7° PO. Nossos resultados mostraram um bom desenvolvimento do aloenxerto até o 5° PO, quando a resposta de rejeição aguda alterou a análise do processo de desenvolvimento. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:526–529 2003
Short‐term immunosuppression after rat parathyroid allotransplantation
Authors: Timm Stephan , Otto Christoph , Begrich Daniel , Illert Bertram , Hamelmann Wulf , Ulrichs Karin , Thiede Arnulf , Timmermann Wolfgang 
Published: October 2003

AbstractThe aim of this study was to evaluate whether short‐term postoperative immunosuppression is able to sufficiently prolong graft survival after experimental allogeneic parathyroid transplantation. Heterotopic parathyroid transplantation was performed in 6 groups: 1) syngeneic control Lewis (LEW) to LEW; 2) allogeneic control Wistar‐Furth (WF) to LEW; 3–5) WF to LEW plus short‐term immunosuppression, postoperative days 1–13 (cyclosporine 5/10/20 mg/kg); and 6) WF to LEW plus 10 mg/kg CyA from preoperative day 7 to postoperative day 7. Graft function was examined up to 60 days; histological and immunohistological examination was performed on all grafts with impaired function. Graft function after syngeneic transplantation was indefinite, while recipients of allogeneic grafts turned hypocalcemic after 13 ± 2 days. With immunosuppression, graft function was 21 ± 2 days (groups 5 and 6) and 28 ± 3 days (groups 3 and 4). Histologically, a cellular infiltrate responsible for graft destruction was found. The results show that indefinite parathyroid allograft survival cannot be achieved by short‐term immunosuppression alone. Whether the combination of an additional graft pretreatment and immunosuppression has an impact on graft function will be further examined. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:503–507 2003
Needles to promote ventricular blood into the schemic myocardium applied in a rat heart transplant model: An acute observation
Authors: Lee S. , Pivetti C.D. , Hong I.C. , Yoo C.H. , Kim K. , Nam S. , Bai S. , Niewiadomski S.T. , Wolf P. , Gittes R.F. 
Published: October 2003

AbstractTwo needles were designed in order to revascularize an ischemic myocardium in the event of left coronary artery occlusion. This study was conducted by performing the Lee modified Fox‐Montorsi heart‐lung transplant on 25 San Diego Microsurgical Institute‐bred Sprague Dawley rats that were subjected to left coronary artery ligation in each case. Of these 25 rats, a straight‐porous (SP) needling procedure was applied to 9 heterotopically transplanted rat hearts, and a distinct horseshoe (HS)‐shaped needle application was performed on the remaining 16 heterotopically transplanted rat hearts. This report represents an acute study on the efficiency of these two needles to transmit oxygen‐rich blood from the left ventricle into the ischemic myocardium. Doppler readings for male vs. female transplants showed that the control peak (PK) and mean (MN) kHz values are on the average of 0.20 kHz higher in males than in females. However, control heart rate values in both sexes are approximately equal. Ligation of the left coronary artery caused a dramatic decrease of PK and MN kHz values in both sexes, while heart rate showed no significant decrease from the original control values in response to ischemia. Application of the SP needle showed only a slight return of PK and MN values in both sexes, but heart rate values increased to levels higher than the original control values. The HS needling procedure was able to recover approximately 80% of the control PK and MN kHz values in both sexes. Thus, these data indicate that the HS needle can successfully transmit left ventricular blood into the myocardium. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:443–449 2003
Consecutive en‐bloc liver (30%)‐pancreas‐duodenum‐spleen‐stomach transplant in Lewis rats
Authors: Yoo C.H. , Hong I.C. , Lee S. , Nam S. , Bai S. , Kim K. , Pivetti C.D. , Niewiadomski S.T. , Wolf P. , Gittes R.F. 
Published: October 2003

AbstractIt is well‐known that 30% of the remaining liver mass, following partial hepatectomy, regenerates to full original mass within 2 weeks in rats. In order to carry the transplanted rat liver to repeated transplantation, a technique of combining 30% of the liver with the pancreaticoduodenum and spleen transplantation is performed in this consecutive organ transplantation study. Our laboratory observed several 37‐month‐old transplanted rats by carrying through 2–3 generations, and histological disclosure were made. Because the partial liver transplants did not regenerate after the transplantation with other splanchnic organs, this technique is not so difficult though subsequent surgical maneuvers are needed and the liver histology proved entirely normal in every aspect when followed beyond the rat's life span of 24 months. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:440–442 2003
Changes in microcirculation after ischemic process in rat skeletal muscle
Authors: Nemeth Norbert , Lesznyak Tamas , Brath Endre , Acs Gabor , Nagy Arpad , Pap‐Szekeres Jozsef , Furka Istvan , Miko Iren 
Published: October 2003

AbstractLaser Doppler flowmetry (LDF) is a good method to investigate tissue microcirculation, but it has many standardization and measuring problems. To exclude these effects, we performed a test using LDF on rat skeletal muscle. In 12 CD outbred anesthetized rats, bilateral femoral vessels and the quadriceps femoris muscle were exposed. The left femoral artery and vein were clamped for 1 h by microvascular clips (ischemic side). On the right side, no other intervention was made (control side). An LDF probe was applied on the medial vastus muscle. Short‐term occlusions (2–3 s) were performed before and after the 1‐h clamping and on the control side while LDF curves were registered. The halftimes of ascending curves on the ischemic side were significantly elongated vs. the condition before clamping (P = 0.0007) or the control side (P = 0.0017). Microcirculatory changes caused by 1‐h ischemia were shown by this simple, quick, and well‐reproducible test on rat skeletal muscle.A lézer Doppler (LD) áramlásmérés elfogadott módszer a szöveti mikrokeringés vizsgálatára, bár számos standardizációs és mérési problémája lehet. E nehézségek kizárására kifejlesztettünk egy tesztet patkány harántcsíkolt izomszöveten. 12 CD outbred patkány a. és v. femoralisát és a m. quadriceps femorist feltártuk mindkét oldalon. A bal oldali femoralis ereket microvascularis clippekkel 1 órára leszorítottuk (ischaemiás oldal), míg a jobb oldalon egyéb beavatkozás nem történt (kontroll oldal). A LD mérőfejet a m. vastus medialisra helyeztük. Az 1 órás leszorítás előtt és után illetve a kontroll oldalon rövid időtartamú (2–3 s) occlusiót idéztünk elő, miközben a LD jelet folyamatosan rögzítettük. A felszálló LD görbék 50%‐os értékénél mért idő szignifikánsan hosszabb volt a kontroll oldalhoz (P = 0.0017) illetve a beavatkozás előtti állapothoz képest (P = 0.0007). Ezzel az egyszerű, gyors és jól reprodukálható teszttel az 1 órás ischaemia indukálta mikrocirculációs változásokat sikerült kimutatni patkány vázizomban. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:419–423 2003
Prolonged survival of heart allografts transduced with AAV‐CTLA4Ig
Authors: Chen Zongyou , Lu Lina , Li Juan , Xiao Xiao , Fung John J. , Qian Shiguang 
Published: October 2003

AbstractOrgan grafts transduced with gene‐encoding immunosuppressive molecules are a less toxic approach to preventing graft rejection. Adenovirus vectors have been widely tested with unsatisfactory results, while adeno‐associated virus (AAV) is smaller and elicits a low host humoral response. We constructed an AAV vector containing the mouse CTLA4Ig gene. B10 (H2b) cardiac grafts were transduced with AAV‐CTLA4Ig by coronary infusion. AAV‐LacZ vectors were used as reporters and controls, and the expression of β‐gal was determined by X‐gal staining. Thirty percent to 40% of myocytes displayed strongly positive X‐gal staining after infusion with AAV‐LacZ. Additional infusion with vascular dilator reagents did not improve the transduction rate. Survival of B10 heart allografts transduced with AAV‐CTLA4‐Ig was significantly prolonged in C3H (H2k) recipients. These data demonstrate that AAV vectors can efficiently be transduced into the mouse myocardium by coronary infusion. Graft transduction with AAV‐CTLA4Ig may be a novel approach to preventing allograft rejection. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:489–493 2003