bluuebunny/crossref_metadata_2025 huggingface dataset:
Both paracetamol and ibuprofen are equally effective in managing flu-like symptoms in relapsing-remitting multiple sclerosis patients during interferon beta-la (AVONEX®) therapy
Authors: Reeß J. , Haas J. , Gabriel K. , Fuhlrott A. , Fiola M.
Published: March 2009

Interferon beta-la is an established therapy for patients with relapsing-remitting multiple sclerosis (MS). Adverse effects in the first weeks of treatment are common. This open-label, multicenter, randomized, prospective study compared treatment of flu-like symptoms (FLS) with paracetamol versus ibuprofen administered 48 h within interferon injection. The percentage of patients with FLS was comparable between both treatment groups and improved during the course of the study (baseline: paracetamol 92%, ibuprofen 90%; week 12: paracetamol 60%, ibuprofen 57%). More than 75% of patients receiving either paracetamol or ibuprofen reported no or only mild impairment of daily activities. There was no significant difference in general satisfaction or incidence of additional symptoms (weakness, nausea, headache; paracetamol 84.6% patients, ibuprofen 86.0% patients) between the two groups. A significant overall improvement from baseline to week 12 was observed for all parameters studied (paracetamol and ibuprofen groups were pooled). These results indicate that neither the paracetamol nor the ibuprofen treatment regimen is better. Multiple Sclerosis (2002) 8, 15-18
International consensus statement on the use of disease-modifying agents in multiple sclerosis
Authors: Freedman MS , Blumhardt LD , Brochet B. , Comi G. , Noseworthy JH , Sandberg-Wollheim M. , Soelberg Sørensen P.
Published: March 2009

Objective:To provide recommendations on the use of disease-modifying agents in the management of multiple sclerosis (MS) and to ensure that treatment will be available to those patients who may benefit.Methods:An initial draft of the consensus statement was prepared by the Steering Committee and amended in the light of written comments from a group of MS specialists. At a subsequent workshop, the wording of the consensus statement was discussed, modified if necessary, and the participants indicated their level of support using an electronic voting system. A new draft of the statement was then sent to a much larger group of international opinion leaders in MS for further comment.Results:A number of statements were agreed, which outline the criteria for consideration of disease-modifying therapy for MS and recommendations for treatment. Each statement was accepted completely, or with only minor reservations by 95% or more of those present at the workshop. Conclusions: Periodic reviews and modifications to the statement will be required, as new approaches to the treatment of MS and other therapeutic agents become available. Multiple Sclerosis (2002)8,19-23
A pilot study of recombinant insulin-like growth factor-I in seven multiple sclerosis patients
Authors: Frank JA , Richert N. , Lewis B. , Bash C. , Howard T. , Civil R. , Stone R. , Eaton J. , McFarland H. , Leist T.
Published: March 2009

The purpose of this open-label, crossover study was to determine the safety and efficacy of recombinant insulin-like growth factor-I (rhIGF-I) using magnetic resonance imaging (MRI) and clinical measures of disease activity in seven multiple sclerosis (MS) patients. Monthly clinical and MRI examinations were performed during a 24-week baseline and a 24-week treatment period with rhIGF-I. The primary outcome measure was contrast enhancing lesion (CEL) frequency on treatment compared to baseline. Secondary outcome measures included clinical and MRI measures of disease activity including. white matter lesion load (WMLL), magnetization transfer ratio (MTR), TI-Hypointensity volume, cervical spine cross-sectional area and proton magnetic resonance spectroscopic (MRS) imaging for determining regional metabolite ratios. rhIGF-I (Cephalon) was administered at a dose of 50 mg subcutaneously twice a day for 6 months. rhIGF-I was safe and well tolerated with no severe adverse reactions. There was no significant difference between baseline and treatment periods for any MRI or clinical measures of disease activity. Although rhIGF-I did not alter the course of disease in this small cohort of MS patients, the drug was well tolerated. Further studies using rhIGF-I alone or in combination with other therapies may be of value because of the proposed mechanism of action of this growth factor on the oligodendrocyte and remyelination. Multiple Sclerosis (2002)8,24-29
Asymmetric dimethylarginine (ADMA) accelerates cell senescence
Authors: Bode-Böger Stefanie M , Scalera Fortunato , Martens-Lobenhoffer Jens
Published: March 2009

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase and its accumulation has been associated with cardiovascular disease. We aimed to investigate the role of ADMA in endothelial cell senescence. Endothelial cells were cultured until the tenth passage. ADMA was replaced every 48 hours starting at the fourth passage. ADMA significantly accelerated senescence- associated β-galactosidase activity. Additionally, the shortening of telomere length was significantly speeded up and telomerase activity was significantly reduced. This effect was associated with an increase of oxidative stress: both allantoin, a marker of oxygen free radical generation, and intracellular reactive oxygen species increased significantly after ADMA treatment compared with control, whereas nitric oxide syn thesis decreased. Furthermore, ADMA-increased oxidative stress was accompanied by a decrease in the activity of dimethylarginine dimethylaminohydrolase, the enzyme that degrades ADMA, which could be prevented by the antioxidant pyrroli dine dithiocarbamate. Exogenous ADMA also stimulated secretion of monocyte chemotactic protein-1 and interleukin-8. Co-incubation with the methyltransferase inhibitor S-adenosylhomocysteine abolished the effects of ADMA. These data suggest that ADMA accelerates senescence, probably via increased oxygen radical formation by inhibiting nitric oxide elaboration. This study provides evidence that modest changes of intracellular ADMA levels are associated with significant effects on slowing down endothelial senescence.
Effects of Posterior Tibial Tendon Augmented With Biografts and Calcaneal Osteotomy in Stage II Adult-Acquired Flatfoot Deformity
Authors: Lee Daniel
Published: March 2009

Adult-acquired flatfoot deformity (AAFD) is a well-known condition leading to flexible flatfoot deformity. However, only recently have the function and muscle strength for balancing opposing muscles been more appreciated in laboratory studies. With the advancements in collagen science in tendon structure, the rationale and concept of some of the most common procedures in tendon transfer have been challenged. The current availability of biograft technology has provided an alternative in augmentation procedures instead of sacrificing autologous tendons. This novel approach may offer a viable option in AAFD, delivering much-needed collagen in a degenerative tendon. These biografts have shown ease of use and tissue biocompatibility in many orthopaedic and plastic surgery procedures and may prove to be an adjunct in the surgical option for AAFD.
Bioprosthetic Aortic Valve Infective Endocarditis
Authors: Duarte Rodriguez Joleen
Published: March 2009

Infective endocarditis of the aortic valve usually presents with vegetations attached to the ventricular surface of the valve. Vegetations can be large, pedunculated, and freely mobile, making the risk of embolization high. The author reports a case of bioprosthetic aortic valve endocarditis caused by the rare organism Cardiobacterium hominis with an atypical presentation of the vegetation on the aortic surface .
Development and evaluation of new mask protocols for gene expression profiling in humans and chimpanzees
Authors: Toleno Donna M , Renaud Gabriel , Wolfsberg Tyra G , Islam Munirul , Wildman Derek E , Siegmund Kimberly D , Hacia Joseph G
Published: March 2009

Background

Cross-species gene expression analyses using oligonucleotide microarrays designed to evaluate a single species can provide spurious results due to mismatches between the interrogated transcriptome and arrayed probes. Based on the most recent human and chimpanzee genome assemblies, we developed updated and accessible probe masking methods that allow human Affymetrix oligonucleotide microarrays to be used for robust genome-wide expression analyses in both species. In this process, only data from oligonucleotide probes predicted to have robust hybridization sensitivity and specificity for both transcriptomes are retained for analysis.

Results

To characterize the utility of this resource, we applied our mask protocols to existing expression data from brains, livers, hearts, testes, and kidneys derived from both species and determined the effects probe numbers have on expression scores of specific transcripts. In all five tissues, probe sets with decreasing numbers of probes showed non-linear trends towards increased variation in expression scores. The relationships between expression variation and probe number in brain data closely matched those observed in simulated expression data sets subjected to random probe masking. However, there is evidence that additional factors affect the observed relationships between gene expression scores and probe number in tissues such as liver and kidney. In parallel, we observed that decreasing the number of probes within probe sets lead to linear increases in both gained and lost inferences of differential cross-species expression in all five tissues, which will affect the interpretation of expression data subject to masking.

Conclusion

We introduce a readily implemented and updated resource for human and chimpanzee transcriptome analysis through a commonly used microarray platform. Based on empirical observations derived from the analysis of five distinct data sets, we provide novel guidelines for the interpretation of masked data that take the number of probes present in a given probe set into consideration. These guidelines are applicable to other customized applications that involve masking data from specific subsets of probes.
Micropitting of carburized gears lubricated with biodegradable low-toxicity oils
Authors: Cardoso N F R , Martins R C , Seabra J H O
Published: March 2009

Environmental issues are leading to a growing interest in bio-lubricants, which can have similar or even better performance than mineral and synthetic oils. In this work, the biodegradability and toxicity characteristics of ester-based gear oils are presented and their physical, chemical, and wear properties are compared with those of a commercial mineral oil.

In an earlier work, power loss tests were performed on the FZG test rig, using carburized gears and several different lubricants. The operating temperatures of the oil and of the FZG gearbox wall were measured for different values of the input torque and speed. An energetic model of the FZG test gearbox was developed, taking into account the power loss mechanisms inside the gearbox and the heat flow mechanisms from the gearbox to the surrounding environment. Using this model it was possible to quantify the influence of lubricant formulation on the average friction coefficient between gear teeth.

Gear micropitting tests were performed on the FZG test rig, using carburized gears and different oils. Post-test analysis included the mass loss measurement of the gear, the ferrometric analysis of lubricant samples collected during the tests, and the visual inspection of the gears. The tooth flanks were inspected using surface topography measurements to assess the number and depth of micropits. In comparison with the gear lubricated with mineral oil, the gears lubricated with ester-based oil showed significantly higher mass loss (3—4 times higher), smaller number of micropits, and less deep micropits.

If carefully formulated, biodegradable low-toxicity ester-based gear oils, beside their environmental advantages, enhance gear performance when compared with the mineral lubricant providing (a) lower friction coefficients and lower operating temperatures of gearboxes and (b) lower number of micro-pits (with depths greater than 4 μm). One of the ester-based gear oils passed the FVA gear micropitting criterion.
Abundance of Immunologically Active Alanine Aminotransferase in Sera of Liver Cirrhosis and Hepatocellular Carcinoma Patients
Authors: Kim Hyun Jeong , Oh Sang Wook , Kim Dong Joon , Choi Eui Yul
Published: March 2009

Background: Although alanine aminotransferase (ALT) is a widely used indicator of liver function, ALT enzymatic activity may not always reflect the degree of liver damage. Improved methods or approaches would be useful.

Methods: Monoclonal antibodies (mAbs) to ALT were generated to develop a sandwich enzyme immunoassay system. We used an immunoassay to measure ALT mass concentration and a common biochemical analyzer to assay ALT enzymatic activity in serum samples from patients with liver diseases and healthy individuals. The results from the 2 methods were compared and analyzed by ROC curve analysis.

Results: The ALT sandwich enzyme immunoassay system demonstrated reliable performance in linearity, recovery, and imprecision studies. The ALT activity assay exhibited a higher diagnostic accuracy in acute hepatitis (AH) patients, but the ALT immunoassay exhibited higher sensitivity and specificity in patients with chronic liver diseases. The areas under the ROC curve for ALT mass and enzymatic activity were 0.82 and 0.98, respectively, in AH, 0.99 and 0.52 in hepatocellular carcinoma (HCC), and 0.94 and 0.45 in liver cirrhosis (LC). Serum samples from HCC and LC patients had higher amounts of ALT–immunoglobulin complexes [median A450, 1.7 (interquartile range, 1.4–1.9)] than the other groups [1.3 (interquartile range, 0.9–1.6)].

Conclusions: Our analysis of sera from the HCC and LC patient groups revealed considerable amounts of immunologically active but catalytically inactive ALT. The amount of the ALT–immunoglobulin complex increased with the severity of the liver disease. The 2-site immunoassay method may be useful in the differential diagnosis of some causes of liver disease.
New ELISA for Detecting Primary Biliary Cirrhosis–Specific Antimitochondrial Antibodies
Authors: Dähnrich Cornelia , Pares Albert , Caballeria Llorenç , Rosemann Anke , Schlumberger Wolfgang , Probst Christian , Mytilinaiou Maria , Bogdanos Dimitrios , Vergani Diego , Stöcker Winfried , Komorowski Lars
Published: March 2009

Background: Antimitochondrial antibodies specific for primary biliary cirrhosis (PBC) target the E2 subunits of 2-oxo acid dehydrogenase complexes, in particular the pyruvate dehydrogenase complex (PDC)-E2. Their antigen-specific detection relies on conventional ELISA using purified PDC. More recent assays have employed a hybrid containing the 3 E2-subunits (MIT3). Some PBC sera react with one or the other preparation, suggesting the presence of nonoverlapping epitopes.

Methods: We have developed an ELISA (anti-M2-3E) using a mixture of purified PDC and MIT3 as antigenic targets. We compared this assay to anti-MIT3 alone, conventional anti-PDC, and indirect immunofluorescence using 173 PBC and 247 disease controls.

Results: The anti-M2-3E ELISA showed a 93.6% diagnostic sensitivity compared with 91.3%, 83.8%, and 87.3% for MIT3, purified PDC, or indirect immunofluorescence, respectively, when all specificities are set to 98.8%. By immunoblotting, anti-M2-3E–positive sera unreactive to purified PDC recognized recombinant E2-subunits of the other 2 complexes, whereas those with no reactivity to MIT3 immunofixed PDC subunits E1α or E1β.

Conclusions: The diagnostic accuracy of the anti-M2-3E ELISA for detection of antibodies to 2-oxo acid dehydrogenase complexes exceeds that of conventional ELISA and IFL; its novelty derives from the combination of the MIT3 hybrid and purified PDC.
Standardizing and Harmonizing Terminology: Theory and Practice
Authors: Wright SE , Strehlow RA
Published: March 2009

Description

The question of terminology harmonization within the framework of data exchange and information retrieval is likely to dominate concerns in the field well beyond the turn of the next century. STP 1223 follows in a series of publications resulting from symposia that has been recognized in the world wide terminology community for its excellence, timeliness and relevance.

16 peer-reviewed papers in 5 sections:

• Concept Congruence--Theory and Practice of Terminology

• Design and Management of Terminologies--Varieties and Types

• Harmonization in a Multilingual Environment

• Computer Aided Terminology Work

• Roundtable Discussion.
Special Applications and Advanced Techniques for Crack Size Determination
Authors: Ruschau JJ , Donald JK
Published: March 2009

Description

Presents a compelling range of unique approaches to non-visual crack size measurement. Up-to-date improvements over standard, well-used methods are also discussed. Ten comprehensive, peer-reviewed papers that explore original and advanced methodology for crack measuring techniques on a variety of materials. Some of the procedures explored include use of: Alternating Current Potential Difference Technique • Improved Load Ration Methods • Ultrasonic Microscopy • AC Magnetic Bridge Device.
Mode I and Mode II Delamination Growth of Interlayer Toughened Carbon/Epoxy (T800H/3900-2) Composite System
Authors: Kageyama K , Kimpara I , Ohsawa I , Hojo M , Kabashima S
Published: March 2009

Delamination is one of the most critical failure modes in a laminated composite structure. In order to improve the interlaminar fracture toughness, the concept of “interlayer” has been applied to thermoset composite materials. In the present paper, the static and fatigue interlaminar fracture characteristics of a interlayer toughened carbon/epoxy, T800H/3900-2, were examined and compared with those of a thermoplastic composite, APC2, as a reference.

Fracture region transition, which is deflection of the crack path from interlayer to intralaminar, is observed in the static Mode I interlaminar crack growth of T800H/3900-2. Mode I interlaminar fracture toughness, GIR, decreases during the propagation in relation to the decrease of the interlayer fracture surface area.

The Mode II crack growth resistance curve (R-curve) was obtained under the constant CSD rate by applying the stabilized ENF test. The remarkable fracture region transition is not observed in the Mode II R-curve of T800H/3900-2, and the toughened carbon/epoxy composite exhibits excellent crack growth resistance under Mode II loading.

The Mode I fatigue crack growth rate of T800H/3900-2 was expressed as a function of the maximum energy release rate during cyclic loading. The fracture region transition is also observed. The transition in the fatigue test was completed after a shorter crack extension than that in the static test.
Atmospheric Corrosion of Bolted Lap Joints Made of Weathering Steel
Authors: Knotkova D , Vlckova J
Published: March 2009

For certain types of steel structures the application of weathering steels is especially suitable. These are electrical transmission towers, masts, bridges and other structures, used in outdoor exposure, where brown color is appreciated and no maintenance is necessary.

Proposals for the use of weathering steels for various types of steel structures are based mainly on the results of field corrosion tests (outdoor and under sheds) in which a significantly higher corrosion resistence of weathering steels as compared to that of plain carbon structural steel, has been proved in the atmospheres of low or medium aggressivness.

At bolted joints of certain design exposed to a more corrosive environment, significant defects were found in the crevices which cause even deformation of the joints. After dismantling and pickling, these phenomena were quantified. Recommendations were prepared to minimize these corrosion effects, and also possibilities were considered of increasing the lifetime of structures already affected by crevice corrosion.
Comparison of ASTM Fire Standards with International Fire Standards for Buildings and Contents
Authors: Grayson SJ , Hirschler MM
Published: March 2009

Various organizations throughout the world write fire standards. These include both national and international organizations. In the United States, the most important fire standards writing organization is the American Society for Testing and Materials (ASTM). Fire standards are also, however, developed by the National Fire Protection Association (NFPA), and Underwriters Laboratories (UL), but they are often similar to the ones issue by ASTM. The International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) are the primary bodies making international standards. In some cases individual countries subordinate their national standards to regional organizations, such as is the case in Europe, where CEN and CENELEC create some standards that are applicable throughout the European Community (and even beyond it). All these organizations create various types of fire standards, mainly guidance documents and test methods addressing most of the major fire properties. It is interesting that new fire standards throughout the world all tend in the same direction: away from simple ranking tests and geared towards test results that can be used as input into mathematical fire models or fire hazard assessment and research, and real-scale tests to be used for validation of the small scale tests and the models. This is particularly noticeable when considering the geometrical increase in work on heat release standards, a type of fire property which is crucial for fire safety, but was unknown only a few years ago. This paper compares ASTM fire standards (and others still at the draft stage) with standards already issued, or being prepared, by the major international standards organizations (ISO and IEC), and discuss their relevance and applicability.
Investigation of the Relationship Between Field Performance and Laboratory Aging Properties of Asphalt Mixtures
Authors: Kliewer JE , Bell CA , Sosnovske DA
Published: March 2009

Short- and long-term aging procedures were developed at Oregon State University under the Strategic Highway Research Program (SHRP) A-003A project. Several alternative methods for short- and long-term aging of asphalt-aggregate were examined. These were subjected to extensive laboratory and field validation test programs. Laboratory validation was done with an extensive testing program using 8 asphalts and 4 aggregates. Field validation utilized 20 test sites and compared the modulus of field aged and laboratory aged specimens.

For short-term aging a procedure of curing the loose mix in a forced draft oven at 135°C for 4 hours was recommended. For long-term aging, oven aging at 85°C for 4 days was recommended to represent projects of about 10 years old. Alternative procedures may be appropriate in some situations. Long-term oven aging for 2 days at 100°C could be used for stiff mixes, whereas a low pressure procedure of 4 days at 85°C may be necessary for soft mixes.

The results of the asphalt-aggregate mixture testing presented herein show that the aging of the mixture is dependant on both the asphalt and the aggregate. Also, it appears, from the evaluation of data from other SHRP contractors, that the aging and subsequent testing of asphalt alone is not a good predictor of how a mixture will behave due to the effect of the asphalt-aggregate interaction.

Continued monitoring of field projects is needed, particularly for Dry-No Freeze and Wet-No Freeze zones. Increasing the number of sites and total number of specimens tested will facilitate the use of regression analyses to develop performance prediction models.
Promoted Combustion of Pure Metals in Oxygen-Enriched Atmospheres
Authors: Sircar S , Stoltzfus J , Bryan C , Kazaroff J
Published: March 2009

The combustion behavior of several elemental materials was studied using their threshold pressures (minimum pressure required to sustain combustion in 3.2-mm-(0.13-inch) diameter rod) as the ranking criterion in a promoted combustion test apparatus. Test media varied from 100% aviator's breathing oxygen to air and the test pressures varied from ambient to 70 MPa (10,000 psi).
An Assessment of Oil-spill Effects on Pink Salmon Populations Following the Exxon Valdez Oil Spill—Part 2: Adults and Escapement
Authors: Maki AW , Brannon EJ , Gilbertson LG , Moulton LL , Skalski JR
Published: March 2009

This paper presents results of a field program designed to monitor the status of wildstock pink salmon populations in Prince William Sound following the Exxon Valdez oil spill. Field counts of spawning salmon were conducted each year from 1989 through 1992 to test for spill effects on the distribution and abundance of pink salmon adults spawning in selected streams in the southwestern portion of Prince William Sound, including streams from the most heavily oiled areas. Counts of whole-stream and intertidal escapement density were statistically compared for 40 study streams in 1989 and for a subset of those streams in successive years. Measurements of residual hydrocarbons were made from stream-bed sediments to test for correlations with spawning behavior.

Adult pink salmon in the postspill years of 1990 and 1991, progeny of the year classes considered most vulnerable to the oil spill, returned in high numbers, with the wildstock spawners exceeding their parent year returns. In 1989, adult returns reflected the relatively weak run for that year with a mean spawner density of 0.68 fish/m2 in reference streams and 0.69 fish/m2 in oiled streams. In 1990, mean escapement density for reference streams was 1.40 fish/m2 and 1.55 fish/m2 for oiled streams, indicating the strongest run of the four study years. Trends in polycyclic aromatic hydrocarbon (PAH) concentrations for the majority of oiled streams show a general decline from 1989 to background levels by 1990. The measured PAH concentrations indicate low-level exposure to residual hydrocarbons that have not produced detectable differences in spawning behavior or escapement between streams from oiled areas compared with unoiled streams.

In Part 1 of this paper, elements of the early lifestage survival of potentially affected year classes of pink salmon were examined by Brannon et al. (this volume). Conclusions indicate measures of early lifestages were largely indistinguishable between oiled and unoiled streams. The early lifestage data, in combination with observations of the strength of postspill returns and analyses of escapement reported herein, are the basis for the conclusion that changes in the wildstock pink salmon population in Prince William Sound could not be attributed to the oil spill.
Application of destruction specific energy for characterisation of concrete paving blocks
Authors: Atici U. , Ersoy A. , Ozturk B.
Published: March 2009

Concrete interlocking paving blocks (CIPB) are used in a variety of commercial, municipal and industrial applications. This study aimed to develop a prescription (optimum parameters of aggregate proportion, water/cement (w/c) ratio and dosage) for producing CIPB based on destruction specific energy (SEdes), strength, hardness and abrasion resistance. In developing countries, CIPB are being produced by a trial and error method, which results in uneconomical and low engineering properties. This may arise as a result of the lack of confidence and the lack of technical experience in the CIPB field. In order to gain these qualifications, optimum water/cement (w/c) ratio and dosages, and optimum aggregate characteristics at different ages are determined for CIPB within the scope of the presented study. Recently defined SEdes, which is estimated from the area (integral) under the stress–strain envelope in unconfined compression test, is used. The splitting and flexural tensile strengths, rebound hardness and abrasion resistance results showed consistency with the SEdes. The optimum parameters of aggregate proportion, w/c ratio and dosage are obtained. Accordingly, the application of SEdes for production of CIPB results in lower cost and higher quality engineering properties for CIPB.
Performance of synthetic macrofibres in reinforced concrete for tunnel linings
Authors: Won J.-P. , Park C.-G. , Lee S.-W. , Jang C.-I. , Kim H.-Y.
Published: March 2009

The aim of this study was to evaluate the effect of synthetic macrofibres in tunnel concrete lining structures. Tunnel concrete linings must be able to resist flexure loads that occur in the ground and should be able to cope with the danger of cracking owing to their wide surface areas. Recent tunnel fires have raised concern because the collapse of the concrete lining structures can affect the safety of the tunnel. In this study, the effect of synthetic macrofibres was examined to improve the performance of the concrete lining in tunnels. By changing the fibre mixing ratio, it was found that a level above 0·5% was effective in controlling cracks. The effect of fibre mixing ratio on the flexural capability was also studied and it was found that the fibres were more effective than steel and that 2% mix was the best. The fire resistance of concrete containing synthetic macrofibres was studied and it was shown that the fibres prevented the concrete structures lining the tunnel from spalling.
Uniformity of SCC properties cast in vertical column
Authors: Valcuende M. , Parra C. , Ferrer A.
Published: March 2009

This experimental work examines the homogeneity of self-compacting concretes in vertically cast columns. Eight different concretes were used, four self-compacting (SCC) and four normally vibrated (NVC). The distribution of pore sizes, the compressive strength, the rebound hammer and the bond strength were determined at different locations on 1500 mm high columns. It was found that SCCs have a slightly more uniform porous microstructure along the height. Moreover, up to 100 cm in height the four SCC mixes display a strength distribution comparable to that obtained with control concretes. For greater heights, the loss of strength is lower in SCCs (3·91%) than in NVCs (9·35%). Unlike NVCs, for SCCs the water/cement ratio does not seem to have a significant influence on the variation of strength with height. The top-bar effect is much less marked in SCC, and therefore a change in the factor that takes into account this effect in the formulae used for calculating the anchorage length of the reinforcement is proposed for these concretes.
Anchorage slip effect in RC structures
Authors: Kwak H.-G. , Na C.-K.
Published: March 2009

A numerical model that can simulate the cracking behaviour of a reinforced concrete (RC) structure subjected to monotonic loading is introduced. A criterion to take into account the biaxial behaviour of concrete is designed on the basis of Kupfer's experimental results, and the equivalent uniaxial stress–strain relationship with a tension-stiffening effect is used for an effective simulation of the inelastic behaviour induced from the cracking of concrete. Moreover, an improved numerical model to implement the bond-slip effect in RC structures, in which the consideration of the bond-slip effect is virtually impossible in the numerical analysis as the reinforcing steels are uniformly distributed through the entire domain, is developed in this paper. Instead of using the bond-link elements that connect the concrete and steel nodes with the spring elements, a relationship between the steel stress and the end-slip obtained from an idealised pull-out specimen is implemented at the end face of RC structures. The use of these boundary spring elements makes it possible to simulate precisely the cracking behaviour of the RC structures affected most by the bond-slip. Finally, correlation studies between the numerical results and the experimental results are conducted in order to verify the soundness of the introduced boundary spring element model.
Study of the Effect of Inhibitor on Erosion-Corrosion in CO2-Saturated Condition With Sand
Authors: Neville A. , Wang C.
Published: March 2009

CO2 corrosion inhibitors are widely adopted in production and processing facilities in the oil and gas industry. The challenge is that under multiphase flow (liquid/sand) and high shear-stress conditions, successful application of inhibitors can be difficult. Under such severe erosion-corrosion conditions, the total material damage is identified as being associated with electrochemical corrosion, solid particle erosion, and synergistic effects between the two.

To investigate the possibility of using corrosion inhibitors to reduce erosion-corrosion, this study has characterized the corrosion phenomena occurring at the carbon steel-electrolyte interface under erosion-corrosion conditions. AC impedance was used to provide mechanistic information of corrosion with absence and presence of a commercial corrosion inhibitor in erosion-corrosion conditions in a CO2-saturated brine. Experiments were conducted using a rotating cylinder electrode cell containing sand at different temperatures, rotational speeds and with various inhibitor concentrations. Four commercial inhibitors have been investigated.

In this work, the potential for applying corrosion inhibitors for the reduction of material loss in erosion–corrosion is assessed and the role of the inhibitor in reducing corrosion, erosion, and interactive mass-loss mechanisms is discussed.
Investigation of Swirl Flows Applied to the Oil and Gas Industry
Authors: Surendra Meher , Falcone Gioia , Teodoriu Catalin
Published: March 2009

The work presented in this paper is part of a larger research project which is aimed at finding solutions to problems associated with liquid loading, erosion at pipe bends caused by sand particles, and phase separation. The work uses computational fluid dynamics (CFD) to design solutions that can reduce or eliminate the aforementioned problems. Here, the results from CFD simulations of two-phase air and water flows are critically analyzed through comparison with the results from experiments carried out by Falcone et al. (2003) using the ANUMET concept.† The entire experimental setup is modeled within the CFD simulation and flow rates for water and air are taken from the data used for the experiments. Important variables such as pressure drop and fluid film thickness, which were monitored closely during the experiments, are obtained from the CFD simulations and compared with the experimental results. The results presented in this paper provide insights into the physics of two-phase swirl flows, identifying areas of research that still need to be addressed.
Paraffin Cleanout in a Single Subsea Flowline Using Xylene
Authors: Bailey J. Claire , Allenson Stephan J.
Published: March 2009

Paraffin deposition was found in the RedHawk #2 subsea flowline and was successfully removed using a xylene slug swept by produced gas from the well. Testing indicated that the problem resulted from the interaction between glycol and produced condensate. Overtreatment with glycol and low produced water volumes contributed to the precipitation of paraffin and eventual plugging of the flowline.

The objective of this procedure was to clear the restriction by pumping a slug of xylene into the flowline and producing the well to carry the solids to surface. Glycol can react negatively with the condensate in some dry gas wells, resulting in paraffin precipitation. When there is sufficient water present to mix with the glycol the problem does not occur; however, a lack of water causes the glycol to react with the condensate and form paraffin. Clearing the restriction would eliminate a pressure drop in the flowline, thus allowing the well to produce at optimal rate and prolonging the well's life. All work was performed from the host spar facility using temporary separation equipment and platform methanol pumps.

The RedHawk flowline restriction was successfully removed using two 25-bbl xylene slugs which were swept from the flowline with produced gas from the well. With the restriction removed, 982 psi of frictional loss was regained and the well was returned to optimal production. The deposition appears to be reoccurring, although at a much slower rate than before. However, any further reduction in glycol usage would not guarantee effective hydrate inhibition. Changing hydrate inhibitors is impractical because of platform equipment, and annual cleanouts are a more cost effective option.

It is quickly becoming critical to develop means of cleaning single flowline systems with highly efficient and low-cost methods. By understanding new problems that arise and putting new solutions into practice, operators can extend the life of some wells and avoid significant downtime and workover costs.
Cover Crops and Organic Mulch to Improve Tomato Yields and Soil Fertility
Authors: Wang Qingren , Klassen Waldemar , Li Yuncong , Codallo Merlyn
Published: March 2009

Cover crops and organic mulches (OMs) have been reported as a means to reduce inputs and increase soil quality. A field experiment was conducted to elucidate the effects of summer cover crops and organic compost on winter fresh market tomato (Lycopersicon esculentum Mill.) yields and quality. Cover crops were sunn hemp (Crotalaria juncea L.), velvetbean (Mucuna pruriens var. utilis), cowpea (Vigna unguiculata L.), and sorghum sudangrass [Sorghum bicolor × S. bicolor var. sudanense (Piper) Stapf.], and compost was applied at 25, 50, and 75 t ha−1. Sunn hemp accumulated up to 190–319 kg ha−1 of N, which was greater than that by sorghum sudangrass (38–110 kg ha−1). The tomato total marketable yields increased 49–82 and 71–85 t ha−1, respectively, in 2 yr. The application of OM at 75 or 50 t ha−1 increased tomato yields compared with that at 25 t ha−1. Yields of extra‐large tomato fruits, especially at the first harvest during the early winter, were improved by growing sunn hemp or applying the composts. However, no interaction between cover crops and OM was observed for tomato marketable yields or quality. Soil organic C increased when OMs were applied compared with the plastic mulch (PM), whereas total soil N and organic C:N ratio were unaffected by any treatment. These results suggest that either the production of cover crops, especially sunn hemp, or the application of compost at high rates can improve winter fresh market tomato yields and quality and advance organic farming.
Food and drugs
Authors: Djakovic-Svajcer Kornelija
Published: March 2009

Food can exert a significant influence on the effects of certain drugs. The interactions between food and drugs can be pharmacokinetic and pharmacodynamic. Pharmacokinetic interactions most often take place on absorption and drug metabolism levels. Absorption can be either accelerated or delayed, increased or decreased, while drug metabolism can be either stimulated or inhibited. The factors which influence food-drug interactions are as follows: composition and physic-chemical properties of drugs, the interval between a meal and drug intake and food composition. Food consistency is of lesser influence on drug bioavailability than food composition (proteins, fats, carbohydrates, cereals). Important interactions can occur during application of drugs with low therapeutic index, whereby the plasma level significantly varies due to changes in resorption or metabolism (e.g. digoxin, theophyllin, cyclosporin) and drugs such as antibiotics, whose proper therapeutic effect requires precise plasma concentrations.
About quality of life and specificities of its measurement in children
Authors: Kvrgic Svetlana , Niciforovic-Surkovic Olja
Published: March 2009

The concept and definition of quality of life have not been coordinated yet so measurement indicators have not been. Quality of life concept The concept of quality of life is mostly understood as a multidimensional construct reflecting several domains of life. Quality of life in general includes all factors influencing person's life (economic, political, religious), while health related quality of life includes only factors which influence health. Each domain is measured separately by most authors, which is followed by transformation of every domain into a quantitative value. Quality of life measurement in children Quality of life measurement in children population is associated with numerous difficulties. As for adults, measuring quality of life in children must include measuring health status, so a comprehensive generic instrument must include full spectrum of health status. Beside that these instruments must be applicable study for children of different gender age and culture. Those who design a must consider who is the most appropriate respondent (child or parent), what is the optimal mode of administration, whether respondent will understand questions and whether questionnaire length is appropriate. Conclusion Quality of life is getting a more and more important place in medical investigations. Quality of life measurement in children population is still insufficiently explored and associated with numerous methodological problems. The existing instruments for quality of life measurement in children significantly differ, and their selection must depend on their psychometric characteristics.
Sense of responsibility in health workers source of job stress
Authors: Nedic Olesja , Jocic Neda , Filipovic Danka , Solak Zdravko
Published: March 2009

Job stress is a great problem in developed countries of the world, but in Yugoslavia, it is increased due to additional reasons associated with economic crisis in the society. Health services and health workers are in particulary difficult conditions. The aim of this paper was to examine sources and causes of job stress in health workers. Material and methods The research was undertaken among health workers treated at Health Centre "Hospital" in Novi Sad. The study group included health workers - doctors nurses and laboratory workers, and the control group included the rest of non-medical staff. Adapted Siegrist questionnaire was used. Three factors were examined: extrinsic efforts (disturbances at work, sense of great job responsibility and the need for overtime work); intrinsic efforts (major criticism, thinking about the job from the early morning, getting nervous because of minor problems, discontentment because of unsolved problems at work, relaxation at home and so on), and low reward (respect from the superiors and colleagues, support and security at workplace). Answers were scored indicating intensity (high, moderate, low, not at alt). Statistic analysis included testing the level of significance in health workers in relation to non-medical staff (t test and Fisher's exact test). Results Applying the scoring system it has been established that health workers are exposed to greater job stress, great sense of very high job responsibility and frequent overtime work (p<0,001) than the control group. In regard to answers from the second group - intrinsic effort and low reward, there was no statistical significance between the study and control group. Generally high level of risk factors was established, especially presence of one or more risk factors. Discussion Job stress increases absenteeism, reduces work productivity, causes higher expenses of medical treatment, rehabilitation and staff retraining. It is of great importance to identify factors which cause job dissatisfaction in order to decrease them to the lowest level. Conclusion High sense of responsibility in health workers is a source of job stress.
Wall stress in ischemic heart disease
Authors: Vindis-Jesic Marija , Dejanovic Jadranka , Cemerlic-Adjic Nadica , Jung Robert
Published: March 2009

Introduction Wall stress or wall tension is a conception derived from physics (Laplace's law) and represents the systolic force or work per surface unit. It is the systolic force made by myocardial tissues. Stress increase indicates enlargement of the left ventricle or increase of intracavitary pressure. Material and methods This investigation included 170 subjects; control group consisted of 50 patients (pts) with normal coronary angiographic finding without valvular anomalies and the examination group included 120 pts with coronary disease. Transthoracic echocardiography was performed in the left lateral position using computerized Hewlett Packard Sonos 1000 apparatus. Invasive hemodynamic procedure was performed using General Electrics CGR 300. Meridional and equatorial systolic and diastolic stress were calculated according to Grossman formula. Results The meridional end-diastolic equatorial stress was 18.55(12.12 dyn/cm2 x 10? in the control group, while in coronary patients it was 28.15?13.42 dyn/cm2 x 10?. In healthy persons the meridional end-systolic stress established by echocardiography was 190.37?23.15 dyn/cm2 x 10?, while in coronary patients 203.82?17.88 dyn/cm2 x 10?. End-diastolic equatorial stress was 34.32?17.18 dyn/cm2 x 10? in the control group and 46.13(17.82 dyn/cm2 x 10? in coronary patients. Systolic equatorial stress in the control group was 357.42(32.15 dyn/cm2 x 10? and in coronary patients 385.34(35.72 dyn/cm2 x 10?. The same parameters determined by invasive hemodynamic procedure were slightly higher, but without statistical significance in relation to the values determined by echocardiography (P>0.05). Conclusion Values equatorial and particulary meridional stress were higher in coronary patients in relations to healthy persons, but without significant difference. The correlation coefficients of all investigated parameters established by noninvasive 2D echocardiography and invasive hemodynamic procedure were in one domain of medium high values. meridional stress increases in coronary patients equatorial in hypertensive patients or valvular anomalies with severe myocardial hypertrophy. In regard to high correlation between these two techniques, echocardiography may be considered a highly reliable method in evaluation of wall tension.
Clinical significance of adenoviral infections
Authors: Brkic Snezana , Vukobratov Zita , Preveden Tomislav , Jovanovic Jovana , Vukadinov Jovan , Kovacevic Nadica
Published: March 2009

Introduction The aim of this article was to point to ubiquitous adenoviral infections and to give a literature overview. Adenoviral infections present with a variety of clinical manifestations, causing many differential diagnosis problems. Diagnosis and epidemiology In our country diagnosis is made using the complement fixation test (CFT), which detects antibodies due to solubile group specific antigen. In acute infections, we need two sera samples given in 2 weeks period with 4-fold rise or fall in titers. Due to many asymptomatic infections which can give increased titer by CFT, many physicians think that patients have a persistent infection. Persistent adenoviral infections need not be accompanied by any special clinical symptomatology. However, adenoviral infections still play an important role in acute respiratory infections. The most severe respiratory infection is pneumonia which can be associated with acute respiratory distress syndrome and death. Disseminated adenoviral diseases appear in 2.5% of all adenoviral infections with the same percentage between immunocompetent and immunocompromised persons. In immunocompromised persons adenoviral infections manifest as haemorrhagic cystitis, fulminant or acute hepatitis or meningoencephalitis. Therapy and conclusion We still don't have a special treatment for these kinds of infections. Variety of antiviral drugs with controversial effects have been reported in management of adenoviral infections in immunocompromised persons. In USA adenoviral vaccine has been excluded from vaccine schedules among military personnel, but morbidity and the first two deaths due to these infections in the last 30 years reported by MMWR in 2000, may change this policy.