bluuebunny/crossref_metadata_2025 huggingface dataset:
Serum ras (p21) as a Marker for Occupationally Derived Lung Cancer?
Authors: Schneider Joachim , Presek Peter , Braun Alexandra , Löffler Simone , Woitowitz Hans-Joachim
Published: October 2004

Certain subsets of the population are especially sensitive to carcinogens, and this can be determined using molecular biological methods. In the literature there has been evidence presented for the use of p21ras (ras) as a tumor marker for human carcinogenic substances such as asbestos, polycyclic aromatic hydrocarbons, and vinyl chloride in the workplace. In this study we have examined whether serum ras could serve as a biomarker for the early detection of occupationally derived lung cancer, with an emphasis on Schneeberger (radon-induced) lung cancer.

Sera were taken from 65 male tumor patients. Fifty-nine patients suffered from primary lung cancer (including 18 patients with Schneeberger lung cancer and 12 patients with asbestos-related lung cancer). Additionally, 29 patients with non-malignant lung disease, and a healthy control group (44) including 32 former uranium miners of SDAG Wismut exposed to ionizing radiation (radon and its decay products) were examined. Ras protein was determined via three different methods: 1) immunoprecipitation followed by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting; 2) SDS-PAGE using 5–17% gradient gels followed by Western blotting; 3) pre-incubation with Blue Sepharose, SDS-PAGE on 5–17% gradient gels, and Western blotting.

The results show that 1 ng ras protein was measurable in serum standards. This protein could not be detected in patient sera or in sera from any of the study groups. Thus, ras cannot be considered useful as a marker for the early detection of asbestos-induced or Schneeberger lung
Influence of in vivo Hemoglobin Carbamylation on HbA1c Measurements by Various Methods
Authors: Chachou Abdelhalim , Randoux Christine , Millart Hervé , Chanard Jacques , Gillery Philippe
Published: October 2004

Increased carbamylated hemoglobin formed in erythrocytes during uremia may interfere with Hba1c assays, but few studies compared directly both parameters. We measured carbamylated hemoglobin by HPLC in 45 non-diabetic uremic patients (16 with acute and two with chronic renal failure, 27 with transplant recipients) as 57.8 ± 22.3 μg carbamylvaline/g Hb (mean ± standard deviation) vs. 31.6 ± 5.1 in 15 controls (+83%, p < 0.001). In these samples, HbA1c was evaluated by three ion-exchange HPLC methods, 1: Diamat (BioRad), 2: A1c2.2 (Tosoh) and 3: HA8140 (Menarini), and one immunoassay method (Tinaquant II Roche). Whichever the method, mean HbA1c values obtained increased in patients with high (> 60 μg carbamylvaline/g Hb) vs. low (< 45) carbamylated hemoglobin values (+0.08 to 0.25% of total Hb), but differences were not significant. Minor peaks on the chromatograms were however increased in parallel to carbamylated hemoglobin. HbA1c values over 6% were found in 4, 1, 2 and 0 samples, with HPLC 1, 2, 3 and immunoassay, respectively. Fructosamine values were not significantly altered. Our results show that Hb adducts, whether due to carbamylation or to other chemical reactions, interfere to a variable extent with different HbA1c assay methods, and confirm that HbA1c values should be interpreted with caution in uremic patients.
Comparison of the Abbott IMx® and a High-Performance Liquid Chromatography Method for Measuring Total Plasma Homocysteine
Authors: Blanco-Vaca Francisco , Arcelús Rosa , González-Sastre Francesc , Ordóñez-Llanos Jordi , Queraltó-Compañó Josep M.
Published: October 2004

The determination of the total concentration of plasma homocysteine is of interest in a variety of clinical circumstances, especially, in the evaluation of the risk of cardiovascular disease. However, most of the methods available to date, many of them chromatographic, are not well suited for the majority of clinical laboratories. Several automated methods are now or will be, shortly, commercially available. We have compared one of them, the fluorescence polarization immunoassay (FPIA) adapted to the IMx® analyzer (Abbott Laboratories), with the high-performance liquid chromatography (HPLC) method with fluorescent detection currently used in our laboratory. The results show that the FPIA-IMx® method is less imprecise and slightly more sensitive than the HPLC. The comparison of 67 clinical plasma specimens indicated that there is a proportional error disagreement between FPIA-IMx® and HPLC (FPIA=1.19 HPLC + 0.92; confidence region for slope and y-intercept were, respectively, from 1.06 to 1.31 and from−0.06 to 2.32). The nature of this error is not explained by the experiments performed to study the inaccuracy of both methods, which included the investigation of dilution parallelism, analytical recovery and cross-reactivity. The different results of homocysteine concentration obtained with FPIA-IMx® and HPLC must be taken into account when a change of methodology is under consideration.
Biochemical Composition and Electrolyte Balance of "Unstimulated" Whole Human Saliva
Authors: Rehak Nadja N. , Cecco Stacey A. , Csako Gyorgy
Published: October 2004

The biochemical composition of "unstimulated" whole saliva was determined in healthy adult subjects. Based on their relative concentration, salivary analytes could be classified into three arbitrary categories: concentration lower than in serum (saliva/serum ratio < 0.5; 12 analytes), similar to serum (ratio = 0.5–1.5; five analytes), and higher than in serum (ratio > 1.5; five analytes). Consistent with local production, an elevated lactate dehydrogenase (LDH) activity in the saliva was associated with a non-serum like LDH isoenzyme pattern: LDH5 >> LDH4 > LDH3 >> LDH2 > LDH1. Compared with serum, the concentrations of hydrogen (as reflected in the pH), potassium and inorganic phosphorus were much higher (saliva/serum ratio ≥ 3), whereas that of sodium, total magnesium, chloride, and total carbon dioxide were lower (saliva/serum ratio ≤ 0.3). The concentration of ionized calcium was similar in saliva and serum (saliva/serum ratio = 0.8), while ionized magnesium was unmeasurable in saliva. The salivary ionized calcium fraction was higher (0.76) than previously suggested (0.51). The difference between the main salivary cations (potassium, sodium), and anions (phosphate, chloride) was similar to serum (anion gap: 4 vs. 11 meq/l). Highly significant (p ≤ 0.012) correlations occured among salivary pH, dihydrophosphate, total calcium, and potassium. Our data suggest that calcium, potassium, chloride and phosphates are the major salivary complex-forming ions. The major compositional differences between serum and saliva show that saliva is not a passive "ultrafiltrate" of serum and salivary constituents may play a distinct physiological role.
Evaluation of a New Simple and Rapid Enzyme-Linked Immunosorbent Assay Kit for Neopterin Determination
Authors: Westermann Jürgen , Thiemann Frank , Gerstner Ludwig , Tatzber Franz , Kozák Ivan , Bertsch Thomas , Krüger Christian
Published: October 2004

A new commercially available enzyme-linked immunosorbent assay (ELISA) kit has been evaluated for the measurement of neopterin concentrations in serum, plasma and urine. This competitive ELISA is technically simple, requires only small sample volume and is rapid to perform. The assay procedure consists of sequential 1.5 h and 10 min room temperature incubation steps. The ELISA is accurate, sensitive, specific, and precise. Linear regression analysis of neopterin concentrations measured with the new ELISA and with an established method yielded a highly singificant correlation (r = 0.99). The new assay is applicable to ELISA workstations, thus enabling determination of neopterin in large series of samples. The neopterin ELISA kit has been used in routine laboratory testing of blood donations in a blood bank.
FESCC Survey on Accreditation and Post-Graduate Training in Clinical Chemistry in European Countries
Authors: Rossier Michelle , Blaton Victor , Franzini Carlo , Queralto José M. , Palicka Vladimir
Published: October 2004

Promotion of the professional growth and development of specialists in the field of clinical chemistry in European countries, and harmonisation of quality assessment and accreditation procedures are listed among the main goals and activities of Federation of European Societies of Clinical Chemistry (FESCC), according to its 1999–2000 strategic plan.

The European countries that are members of the European Union are in the process of establishing the "European Register for Clinical Chemists", based on minimum standards of education, training and experience as defined by the European Communities Confederation of Clinical Chemists (EC4). Many other European countries would like to adapt their system of professional education to this model. Data on postgraduate training in EC4 FESCC members have already been gathered in 1998. However, at the present time, there is no detailed knowledge of pre- and post-graduate professional education of specialists in clinical chemistry in the non-EC4 European countries.

FESCC launched a survey in July 1998 in order to gather this information with the hope to start a database about existing systems. All FESCC members received the same questionnaire on accreditation (seven questions) and non-EC4 FESCC members received an additional questionnaire with 11 questions related to post-graduate training in clinical chemistry.

The response rate of the 35 FESCC member countries was 93% from the 15 EC4 members (14 responses/15 countries) and 80% from the 20-non-EC4 (16 responses/20 countries). The heterogeneity of the data on post-graduate training in clinical chemistry indicates that a great effort will be needed before harmonisation is reached. These results, however, will provide an interesting basis for further discussion and promotion of post-graduate training in clinical chemistry.

The data provided on accreditation show that the total number of accredited laboratories was relatively low in EC4 countries and even lower in non-EC4 members. It was not surprising to see that the number of accredited laboratories was the highest in the two countries which started accreditation the earliest (i.e. Sweden and UK, 1992). This situation, however, is changing at a fast rate in most countries and the number of the accredited sites is expected to increase rapidly in the next few years.
Effect of Soluble Nutrient Content in Wood on its Susceptibility to Soft Rot and Bacterial Attack in Ground Test
Authors: Terziev Nasko , Nilsson Thomas
Published: October 2004

The objective of the study was to investigate whether soluble sugars and nitrogenous compounds in wood have an impact on susceptibility of wood to decay in ground contact, which is important in the field of test methodology and standardization.

Kiln drying of Scots pine planks caused a distinct gradient of low-molecular weight (LMW) sugars and nitrogenous compounds in the 0–2 mm zone at the surface of the timber, whereas the deeper zones had constant and low contents of soluble substances. Strips, containing different content of soluble nutrients, were cut and exposed in two types of soil; the former one being rich in soft rot fungi, the latter one being rich in soft rot fungi and bacteria.

The strips rich in nutrients showed an average of 16 % of mass loss whereas samples poorer in nutrients were less affected (8–9 %) after 120 days of exposure in the soil rich in soft rot fungi. A pure culture test with the soft rot fungus Phialophora mutabilis confirmed the above-mentioned observation. The result is in favour of taking samples with approximately equal content of soluble nutrients to decrease the variability of test results, e.g., mass losses.

The garden compost, rich in both soft rot fungi and bacteria, caused severe mass loss (40–48 %) of the strips after 120 days of exposure. No difference in the mass losses of the samples was measured. The choice of test soil as well as the nutrient status of the samples can lead to completely different results and, consequently, conclusions.
Carboxylic Acids of Moroccan Pinus Pinaster Bark Extract
Authors: Benlarbi R. , Fechtal M. , Meziane D. , Istambouli A.
Published: October 2004

In this work, carboxylic acids of the Moroccan Pinus pinaster bark were studied and analysed by High Performance Liquid Chromatography (HPLC), Thin Layer Chromatography (TLC) and Gas Chromatography coupled with Mass Spectrometry (GC-MS). Several acids, such as gallic, p-hydroxyphenylacetic, 3,4-dihydroxyphenylacetic, salicylic, shikimic, protocatechuic, terephtalic, ferulic, p-coumaric, vanillic, caffeic and isovanillic acids, were detected by direct injection of standard products and by studying the mass spectrum of their trimethylsilyl derivatives.
Atmospheric Acetic Acid Pulping of Rice Straw IV: Physico-Chemical Characterization of Acetic Acid Lignins from Rice Straw and Woods. Part 2. Chemical Structures
Authors: Pan Xue-Jun , Sano Yoshihiro
Published: October 2004

Acetic acid lignins from rice straw (RLs), birch (BL) and fir (FL) were chemically characterized by means of elementary analysis, functional groups analysis, alkaline nitrobenzene and permanganate oxidation, Mannich reactivity and other techniques. The results showed that RLs had higher contents of residual polysaccharide and protein, and remarkably fewer acetyl groups than BL and FL. Results of nitrobenzene and permanganate oxidation indicated that RLs were remarkably more condensed than the native lignin in rice straw. In addition, the results of Mannich reactivity showed that RLs were more reactive toward modification than BL and FL, and might be a good raw material for lignin derivatives, such as lignin adhesives and chelating resins.
Rapid Determination of the Lignin Content in Sitka Spruce (Picea sitchensis (Bong.) Carr.) Wood by Fourier Transform Infrared Spectrometry
Authors: Silva João Costa e , Nielsen Bjarne H. , Rodrigues José , Pereira Helena , Wellendorf Hubert
Published: October 2004

The rapid FTIR (Fourier transform infrared) spectroscopy technique was used to indirectly measure the lignin content of Sitka spruce wood samples.

A model was constructed to relate FTIR data to lignin content measured in wood by chemical analysis (i.e. the modified acetyl bromide method), through the application of the principal component regression (PCR) approach to a set of calibration observations. The acetyl bromide method provided lignin determinations ranging from 24% to 34% with a measurement error of 0.6%. A residual standard deviation of 0.8% and an average prediction error of 0.9% were calculated for lignin content when employing the selected PCR model (based on a normalized infrared data set, obtained using the band at 1374 cm−1 as a reference) to indirectly measure this wood property. Furthermore, a large portion of the variability in lignin content was explained by the two principal components retained in the selected calibration model, as indicated by the magnitude (i.e. 0.93) of the coefficient of multiple determination.

The model was subsequently employed to predict the lignin content of wood samples collected in a clonal experiment. Two multivariate diagnostic measures were applied to assess the quality of the individual predictions, and the results indicated that the spectral information contained in the new sample vectors was suitable for use with the selected calibration model.
Lignin Analysis by Permanganate Oxidation. II. Lignins in Acidic Organosolv Pulps
Authors: Bose Samar K. , Wilson Kate L. , Hausch Diane L. , Francis Raymond C.
Published: October 2004

The permanganate oxidation method was used to analyze residual lignins in Norway spruce (Picea abies) organosolv pulps. The pulps were produced by ethanol water solvolysis catalyzed by 0.005M or 0.01M H2SO4 at 175 °C. Condensation reactions of residual lignin occurred at a significant rate when the ethanol volume fraction was 0% but not when it was ≥ 51 %. There was selective removal of uncondensed guaiacyl units when mixtures of 51 %, 76%, and 91% ethanol were used. The condensed units in the native lignin were less reactive and accumulated in the fibers. They constituted > 60 % of the C9 units by the time 80 % delignification was achieved. A limited amount of results are presented for a kraft pulp with hopes of enhancing the credibility of permanganate oxidation as an analytical tool for residual lignins.
Lignin Depolymerization in Hydrogen-Donor Solvents
Authors: Dorrestijn Edwin , Kranenburg Marieke , Poinsot Didier , Mulder Peter
Published: October 2004

The conversion of different types of lignin to monophenolic compounds has been studied between 500 and 650 K, under typical coal liquefaction conditions using 9,10-dihydroanthracene (AnH2) and 7H-benz[de]anthracene (BzH) as the hydrogen-donor solvents. The yield of phenolic compounds was found to increase with the capacity of the hydrogen donor. The application of a polar cosolvent appeared to be beneficial as well. The differences in product distribution could be related to the origin of lignin. The maximum yield amounted to 11 % after 4 h at 625 K using milled wood lignin in AnH2. It has been found that lignin itself is a hydrogen-donating substance and capable of cleaving aromatic ketones such as α-phenoxyacetophenone.
Species Effects on Wood-Liquefaction in Polyhydric Alcohols
Authors: Kurimoto Yasuji , Doi Shuichi , Tamura Yasuo
Published: October 2004

Four softwood and three hardwood species were liquefied using polyethylene glycol (PEG) or glycerol-containing PEG solvent systems as liquefaction reagents under defined reaction conditions: wood / liquefaction reagent / sulfuric acid = 3.00/9.00/0.27 gram, at 150 °C. The percentage residues and hydroxyl numbers were determined as an estimate of polyol value of the solution. The PEG system yielded 10–30% residual materials even under the best reaction conditions since low -OH group content resulted to re-condensation of liquefied wood (LW). The hydroxyl numbers linearly decreased from 210 to 100 mg KOH/g on extended (150 min) reaction time. On the other hand, addition of 10% glycerol to the PEG system resulted in small amount of unliquefied residues (~ 3%) and a stable hydroxyl number, regardless of the wood species tested. In case of 60 min reaction time, the mean residue value was 5.8% and a corresponding mean hydroxyl number of 216.1 mg KOH/g was obtained. This system is deemed suitable for liquefaction of a wide variety of wood species.
Laser Ablation of Machined Wood Surfaces. 2. Effect on End-Grain Gluing of Pine (Pinus silvestris L.)
Authors: Stehr Micael
Published: October 2004

The effect on glue joint strength of removing the layer of cells on end-grain surfaces of wood damaged by machining—the mechanical weak boundary layer (MWBL)—is presented. The wood surfaces have been laser ablated using different types of lasers of different wavelengths. The goal has been to determine whether or not the strength of end-grain glue joints is influenced by the MWBL and to show how the laser wavelength affects the glue joint strength. All tests were carried out with a PVAc-glue with hardener, and two different glue pressures were used. The joints were tested by bending notched and fatigued specimens. The statistical evaluation of the results shows that one laser gave a significantly higher glue joint strength than the others.

One main conclusion is that the glue joint strength could have been improved with a stronger glue. An ESEM-analysis showed that fracture occurred primarily in the glueline and not in the boundary layer.
Multi-Component Mixture Modeling for the Dielectric Properties of Rubber Wood at Microwave Frequencies
Authors: Khalid K.B. , Kabir M.F. , Daud W. M. , Sidek H.A.A.
Published: October 2004

Dielectric properties from 1 to 18 GHz of rubber wood are modeled using generalized mixture equations and also with equations proposed by Weiner, Kraszewski, Looyenga and Landou, Lichtenecker. Dielectric properties were measured with an open-ended coaxial line-sensor in three structural directions longitudinal, radial and tangential and at different moisture contents. The dielectric constants were predicted well by the Weiner model for all structural grain directions and it was found that the degree of binding decreases with increasing frequency. However, the Weiner model cannot be used for predicting the dielectric loss factor at frequencies below 3 GHz. This may be due to the high conductive loss in this frequency region. The lower value of the exponents in generalized mixture equation was found suitable for fitting the experimental data as well as the Kraszewski equation. Values predicted by Lichtenecker equations are in well agreement with the experimental data at higher microwave frequencies. The prediction of dielectric loss factor using Kraszewski, Looyenga equations were not possible at frequencies below 3 GHz since it is dominated by conductive loss. Above 3 GHz, it was well predicted by Kraszewski and Looyenga equations.
Variations in the Mechanical Strength of a Composite Material of Thermoplastic Matrix Reinforced with Woven Glass-Fabric After Being Submitted to Diverse Damage Sequences: A Statistical Analysis
Authors: Garcia MA , Argüelles A , Viña I , Fernández-Canteli A , Viña J
Published: October 2004

The aim of the present study is to characterize statistically the degradation produced in the tensile breaking strength of a material composed of a PEI thermoplastic matrix reinforced with woven glass fiber under a sequential permutation of damage. To do so, the statistical theory of extreme values was applied to the experimental results, which enabled us to calculate the probability of failure of the material. The simulated damage corresponding to said series was the following: fatigue up to one million cycles at a maximum stress of 20% of the tensile strength, impact damage with an energy of 5.07 J, accelerated aging under conditions of 95% relative humidity, a temperature of 70°C for a period of 360 h, and finally, thermal aging at 150°C for 360 h. The experimental results obtained show losses in residual strength of between 20 and 35% of that presented by the material in its original state.
Heat Transfer Characteristics of Sports Apparel
Authors: Zuo J , McCullough EA
Published: October 2004

The protective clothing and equipment required for certain sports may inhibit heat loss from the body and contribute to potentially harmful heat stress injuries. This study measured the thermal resistance (insulation) and evaporative resistance of a variety of sports ensembles worn for football, basketball, baseball, soccer, track, tennis, golf, and cycling. The thermal resistance was measured with a heated sweating manikin in an environmental chamber according to ASTM F 1291. The intrinsic insulation values (Rcl) ranged from a low of 0.018 m2.0 C/W for running/aerobic ensemble consisting of a sports bra and compression shorts to 0.152 m2.0 C/W for a football uniform. The intrinsic evaporative resistance values (Rccl) ranged from 0.004–0.028 m2kPa/W for the same ensembles, respectively. Sports uniforms that cover a large portion of the body surface or provide impact protection substantially reduced heat loss from the body. The data presented in this paper can be used in the solution of heat balance equations to predict physiological responses of athletes when wearing uniforms under different conditions.
Role of Iron for Hydrogen Absorption Mechanism in Zirconium Alloys
Authors: Kakiuchi K , Itagaki N , Furuya T , Miyazaki A , Ishii Y , Suzuki S , Terai T , Yamawaki M
Published: October 2004

The latest PIE results of Zry-2 and HiFi alloy (0.4 %Fe-Zry2) showed that iron addition reduces the hydrogen pick-up ratio. In order to clarify this lower hydrogen absorption mechanism, three types of experiments were carried out for both alloys:

(1) Measurements of the hydrogen pick-up ratio in the pre-transition region using an autoclave.

(2) CPD (Contact Potential Difference) and FBP (Flat-band Potential) measurements of oxide film using a High Temperature Kelvin system and Photocurrent system.

(3) Investigation of hydrogen absorption properties by Sieverts system and corrosion properties by autoclave for intermetallic compounds simulating SPP's Fe/Cr and Fe/Ni ratio in Zry-2 and HiFi.

Autoclave tests showed that the corrosion behaviors of both alloys were similar. However, the hydrogen pick-up ratio depended on not only iron addition but also surface treatment (with and without pickling). Iron addition and non-pickling (as-received) reduced the hydrogen pick-up ratio.

ΔCPD and FBP shifted to the positive side as the result of iron addition, and FBP changed with and without pickling. This difference in surface potential might be caused by the existence of anion vacancy concentration in the oxide film and furthermore may affect the electrochemical potential gradient over the oxide film. This potential gradient might control the proton diffusion in the oxide film.

In the results of the hydrogen absorption tests on intermetallic compounds, Zr(Fe,Cr)2 with a higher Fe/Cr ratio showed lower hydrogen absorption, and Zr2(Fe,Ni) showed higher hydrogen absorption than Zr(Fe,Cr)2. In the results of corrosion tests on intermetallic compounds, Zr2(Fe,Ni) showed a much larger corrosion rate than Zr(Fe,Cr)2. It is considered that Zr2(Fe,Ni)-type precipitate might be oxidized easily in the oxide film, thus it might not contribute to the window for hydrogen absorption, and Zr(Fe,Cr)2 with a higher Fe/Cr ratio would reduce the amount of hydrogen penetrating through SPP at the oxide/metal interface.

Based on these results, a tentative hydrogen absorption mechanism is proposed, explaining both roles of the electrochemical potential gradient over oxide film and the SPP window for the hydrogen absorption.
Life Prediction by Observation and Simulation of Short Crack Behavior in a Low Carbon Steel
Authors: Hünecke J , Schöne D
Published: October 2004

Short fatigue cracks were investigated in a 0.14 wt % carbon steel (SAE 1017) in fine grained condition by optical observation of the surface of smooth specimens under fatigue loading. Axial fatigue experiments were carried out under constant and step amplitude conditions. The lifetime to crack initiation was calculated for each ferrite grain with regard to grain size and orientation. For the calculation of crack propagation, the slip band length (grain size) and the distance between crack tip and next barrier (grain boundary) are taken into consideration. Furthermore, the simulation program includes some geometrical aspects for the description of crack coalescence.
Fatigue Reliability Analysis of an Overload Effect in Welded Joints Including Crack Initiation and Plastic Zone as Random Variables
Authors: Darcis P , Recho N
Published: October 2004

This paper deals with the reliability analysis of the influence of an overload on the fatigue design of welded joints. The modeling of the fatigue life is presented as the sum of four parts: the first one concerns the fatigue life initiation, the second one involves the fatigue life between the initiation period and the overload application, the third one deals with the fatigue life behavior from the overload to the total restoration of the crack growth rate, and the fourth is related to the fatigue life between the end of the retardation zone until the failure. Concerning the modeling of the retardation effect, particular attention is given to the calculation of the effective stress intensity factor. Finally, the developed methodology is applied to the case of welded joints in order to evaluate the importance of considering the overload effect in the reliability analysis.
Periodic Overloads in the Near Threshold Regime
Authors: Tabernig B , Pippan R , Foulquier J , Rapaport A , Sereni S
Published: October 2004

The effect of periodic overloads on the crack propagation behavior in the near threshold regime of long cracks and physically (extrinsically) short cracks is investigated. A 20 Vol. % SiC particle reinforced 359 cast aluminum alloy and a 17 Vol. % SiC particle reinforced 2129 aluminum alloy are examined. In the Paris regime the two alloys exhibit a different behavior. In the 2124 reinforced alloy a reduction of the mean crack propagation rate, which is typical for ductile metals, is observed. On the other hand the mean crack propagation rate accelerates in the 359 reinforced cast alloy, which is caused by generation of micro-cracks during the overload.

In the near threshold regime and at smaller stress intensity ranges in the physical short crack regime the behavior of both alloys is very similar. The effective threshold is not affected by the overload, i.e., if the constant amplitudes are smaller than the effective threshold they do not contribute to crack propagation. If both, the constant amplitudes and the overload amplitudes contribute to crack propagation, the build up of crack closure is affected by the load history.
Overload Effects in Aluminum Alloys: Influence of Plasticity and Environment
Authors: Ranganathan N , Tougui A , Lacroix F , Petit J
Published: October 2004

This paper presents the behavior of selected aluminum alloys when subjected to a single overload, with an aim to highlight the effects of plasticity and environment. The delaying effect of a single overload is given in terms of number of delay cycles. The delay behavior is systematically compared with the constant amplitude crack growth resistance. It is shown that for most of the studied alloys, a strong parallel can be drawn between the constant amplitude crack growth behavior and the overload induced delay. Delay induced by an overload in vacuum is higher than that in air for the 7075 and the 2024 alloys, compatible with stronger constant amplitude crack growth resistance in vacuum. The influence of the elastic-plastic behavior is stronger in vacuum than in air. In the case of the Aluminum Lithium alloy, delay in air is higher than that in vacuum, which is opposite to the behavior under constant amplitude loading. The basic mechanisms governing crack growth in aluminum alloys and their influence on the delay induced by an overload are revealed. The experimental results are compared with a phenomenological model, taking into account the cyclic plastic behavior of materials.
Load History in Fatigue: Effect of Strain Amplitude and Loading Path
Authors: Aubin V , Quaegebeur P , Degallaix S
Published: October 2004

The low-cycle fatigue behavior of a duplex stainless steel, 60% α - 40 % γ, is studied under tension-compression/torsion loading at room temperature and under strain control. It is shown that the duplex stainless steel has an isotropic behavior under cyclic proportional loading. The loading path induces an extra-hardening on cyclic hardening of duplex stainless steel but lower than that on austenitic stainless steels. The effect of loading history is studied in terms of strain amplitude, mean strain, and loading path. It is shown that only histories in strain amplitude and loading path have an effect on the stabilized stress.
Risperidone in the Treatment of Disruptive Behavioral Symptoms in Children With Autistic and Other Pervasive Developmental Disorders
Authors: Shea Sarah , Turgay Atilla , Carroll Alan , Schulz Miklos , Orlik Herbert , Smith Isabel , Dunbar Fiona
Published: October 2004

Objective. To investigate the efficacy and safety of risperidone for the treatment of disruptive behavioral symptoms in children with autism and other pervasive developmental disorders (PDD).

Methods. In this 8-week, randomized, double-blind, placebo-controlled trial, risperidone/placebo solution (0.01–0.06 mg/kg/day) was administered to 79 children who were aged 5 to 12 years and had PDD. Behavioral symptoms were assessed using the Aberrant Behavior Checklist (ABC), Nisonger Child Behavior Rating Form, and Clinical Global Impression-Change. Safety assessments included vital signs, electrocardiogram, extrapyramidal symptoms, adverse events, and laboratory tests.

Results. Subjects who were taking risperidone (mean dosage: 0.04 mg/kg/day; 1.17 mg/day) experienced a significantly greater mean decrease on the irritability subscale of the ABC (primary endpoint) compared with those who were taking placebo. By study endpoint, risperidone-treated subjects exhibited a 64% improvement over baseline in the irritability score almost double that of placebo-treated subjects (31%). Risperidone-treated subjects also exhibited significantly greater decreases on the other 4 subscales of the ABC; on the conduct problem, insecure/anxious, hyperactive, and overly sensitive subscales of the Nisonger Child Behavior Rating Form (parent version); and on the Visual Analog Scale of the most troublesome symptom. More risperidone-treated subjects (87%) showed global improvement in their condition compared with the placebo group (40%). Somnolence, the most frequently reported adverse event, was noted in 72.5% versus 7.7% of subjects (risperidone vs placebo) and seemed manageable with dose/dose-schedule modification. Risperidone-treated subjects experienced statistically significantly greater increases in weight (2.7 vs 1.0 kg), pulse rate, and systolic blood pressure. Extrapyramidal symptoms scores were comparable between groups.

Conclusions. Risperidone was well tolerated and efficacious in treating behavioral symptoms associated with PDD in children.
Neurotoxicities in Infants Seen With the Consumption of Star Anise Tea
Authors: Ize-Ludlow Diego , Ragone Sean , Bruck Isaac S. , Bernstein Jeffrey N. , Duchowny Michael , Peña Barbara M. Garcia
Published: October 2004

Chinese star anise (Illicium verum Hook f.) is a well-known spice used in many cultures. Many populations use it as a treatment for infant colic. Japanese star anise (Illicium anisatum L), however, has been documented to have both neurologic and gastrointestinal toxicities. Recently, concern has been raised regarding the adulteration of Chinese star anise with Japanese star anise. We report 7 cases of adverse neurologic reactions in infants seen with the home administration of star anise tea. In addition, we have found evidence that Chinese star anise has been contaminated with Japanese star anise. More strict federal regulation of the import of star anise into the United States is warranted. Star anise tea should no longer be administered to infants because of its potential danger in this population.
Hyperlactatemia in Human Immunodeficiency Virus–Uninfected Infants Who Are Exposed to Antiretrovirals
Authors: Noguera Antoni , Fortuny Claudia , Muñoz-Almagro Carmen , Sanchez Emilia , Vilaseca M. Antonia , Artuch Rafael , Pou Jordi , Jimenez Rafael
Published: October 2004

Objective. Exposure to nucleoside analogues in fetal or early life has been associated with rare clinically significant mitochondrial toxic effects, mainly neurologic symptoms. Lactate (LA) measurements have been used to monitor nucleoside-related mitochondrial toxicity. Our aim was to determine the prevalence, clinical evolution, and risk factors for hyperlactatemia in our cohort of human immunodeficiency virus (HIV)-uninfected children who were exposed to antiretrovirals.

Methods. We conducted a prospective observational study of 127 HIV-uninfected infants who were born to HIV-infected women. Clinical symptoms suggesting mitochondrial dysfunction were analyzed in routine follow-up, and LA and alanine plasma levels were obtained at 6 weeks, 3 months, 6 months, and 12 months in all patients. Elevated alanine levels, together with hyperlactatemia, suggest chronic mitochondrial injury.

Results. Most (85%) women received highly active antiretroviral therapy (HAART) during pregnancy (mean duration: 31 weeks) and zidovudine during labor (93%). Most (96%) children received zidovudine alone. Hyperlactatemia with hyperalaninemia was detected in 63 children in at least 1 of the measurements. Mean LA levels were significantly higher in children who were exposed to nucleoside analogue reverse transcriptase inhibitors than in control subjects (2.88 vs 1.61 at 6 weeks, 2.78 vs 1.49 at 3 months, 1.89 vs 1.39 at 6 months, and 1.71 vs 1.24 at 12 months; peak levels: 8.06, 10.1, 7.28, and 4.48 mmol/L, respectively). In 44 patients, LA levels progressed spontaneously to normality within the first year of life. Three girls presented a slight and self-limited delay in psychomotor development, with LA peak levels of 7.3, 4.0, and 4.6 mmol/L. Only the gestational use of didanosine was associated with a higher risk of hyperlactatemia.

Conclusions. In our series, almost half of the children (63 of 127) who were exposed to nucleoside analogues developed benign and self-limited hyperlactatemia. When symptomatic, nucleoside analogue–induced toxicity affected neurologic development.
Hand Hygiene Practices in a Neonatal Intensive Care Unit: A Multimodal Intervention and Impact on Nosocomial Infection
Authors: Lam Barbara C.C. , Lee Josephine , Lau Y.L.
Published: October 2004

Objective. Health care–associated infections persist as a major problem in most neonatal intensive care units. Hand hygiene has been singled out as the most important measure in preventing hospital-acquired infection. However, hand hygiene compliance among health care workers (HCWs) remains low. The objective of this study was to assess the frequency and nature of patient contacts in neonatal intensive care units and observe the compliance and technique of hand hygiene among HCWs before and after the implementation of a multimodal intervention program.

Methods. The nature and frequency of patient contacts, the hand hygiene compliance, and hand-washing techniques of HCWs were observed unobtrusively to reflect the baseline compliance and to investigate factors for noncompliance. The intervention consisted of problem-based and task-orientated hand hygiene education, enhancement of minimal handling protocol and clustering of nursing care, liberal provision of alcohol-based hand antiseptic, improvement in hand hygiene facilities, ongoing regular hand hygiene audit, and implementation of health care–associated infection surveillance. The observational study was repeated 6 months after the completion of the intervention program, which extended over 1-year period.

Results. Overall hand hygiene compliance increased from 40% to 53% before patient contact and 39% to 59% after patient contact. More marked improvement was observed for high-risk procedures (35%–60%). The average number of patient contacts also decreased from 2.8 to 1.8 per patient per hour. There was improvement in most aspects of hand-washing technique in the postintervention stage. The health care–associated infection rate decreased from 11.3 to 6.2 per 1000 patient-days.

Conclusion. A problem-based and task-orientated education program can improve hand hygiene compliance. Enhancement of minimal handling and clustering of nursing procedures reduced the total patient contact episodes, which could help to overcome the major barrier of time constraints. A concurrent decrease in health care–associated infection rate and increase in hand hygiene compliance was observed in this study. The observational study could form part of an ongoing audit to provide regular feedback to HCWs to sustain the compliance.
5‐azacytidine supports the long‐term repopulating activity of cord blood CD34+ cells
Authors: Suzuki Motoyuki , Harashima Akira , Okochi Ayumi , Yamamoto Mayuko , Nakamura Shuji , Motoda Ryuichi , Yamasaki Fumiyuki , Orita Kunzo
Published: October 2004

DNA methylation plays important roles in a wide range of biological phenomena, especially in the embryonic development and tumorigenesis. However, correlations between differentiation and DNA methylation have not been clarified well in each differentiation system. In this study, we focused our attention on regulatory roles of DNA methylation in normal hematopoietic differentiation using a demethylating reagent, 5‐azacytidine (5‐AzaC). As a source of hematopoietic progenitor cells, we used CD34+ cells prepared from human umbilical cord blood and examined the effects of 5‐AzaC on the colony‐forming activity and the long‐term culture‐initiating (LTC‐IC) activity of these cells. 5‐AzaC treatment increased LTC‐IC frequency 1.57‐ to 2.50‐fold as compared to the nontreated control. In parallel to this, immunoblotting analysis showed that the intensity of overall DNA methylation decreased after 5‐AzaC treatment. These results indicated the involvement of DNA methylation and demethylation in controlling immaturity of hematopoietic progenitor cells and the usefulness of 5‐AzaC for regulating this immaturity. Am. J. Hematol. 77:313–315, 2004. © 2004 Wiley‐Liss, Inc.
Sickle cell crisis associated with hemophagocytic lymphohistiocytosis
Authors: Kio Ebenezer , Onitilo Adedayo , Lazarchick John , Hanna Maged , Brunson Chris , Chaudhary Uzair
Published: October 2004

Sickle‐beta+ (β+) thalassemia is a double heterozygous genetic disorder characterized by both a qualitative and quantitative abnormality. We present a case of an African American male who was first diagnosed with sickle cell disease (SCD) at the age 23 years when he presented with generalized bone pain, fever, and hepatosplenomegaly. Laboratory findings included thrombocytopenia, microcytic anemia, and markedly elevated ferritin. He was subsequently diagnosed with a sickle‐beta thalassemia hemoglobinopathy. Findings in the bone marrow aspirate and biopsy were consistent with hemophagocytic lymphohistiocytosis (HLH). HLH resolved with the resolution of sickle cell bone pain crisis without use of immunosuppressive therapy. To the best of our knowledge this is the first documented case of HLH associated with sickle cell bone pain crisis. Am. J. Hematol. 77:229–232, 2004. © 2004 Wiley‐Liss, Inc.
Morphological variation and airflow dynamics in the human nose
Authors: Churchill Steven E. , Shackelford Laura L. , Georgi J. Nicole , Black Michael T.
Published: October 2004

Airflow dynamics are recognized as being important to the functioning of the human nose in conditioning and filtering inspired air, yet these dynamics are poorly understood. Despite considerable research on airflow dynamics by otolaryngologists, respiratory physiologists, and toxicologists, major disagreements remain about the nature of airflow in the human nose. Specifically, there is little consensus about the character of nasal airflow regimes (laminar or turbulent) and about the major pathways of airflow through the internal chamber. Additionally, a number of features in the human nose have been argued to enhance airflow turbulence, thus increasing the exposure of moving air to the nasal mucosa and facilitating heat and moisture exchange in cold and/or dry climates. These features include: an inferior orientation of the nares; a nasal sill that is high relative to the floor of the internal nasal chamber; a nasal valve that is small in cross‐sectional area relative to that of the internal chamber; and large, projecting conchae. The claim that these features affect airflow dynamics has never been tested. To clarify the nature of human nasal airflow and to test these claims of functional significance to nasal variation, we studied airflow across physiological flow rates using water and dye flowing through anatomically accurate acrylic models of human nasal air passageways (with adjustment of water flow rates to maintain dynamic similarity). The models were derived from direct casting of the nasal passageways of 10 Caucasian (“leptorrhine”) cadavers (six male, four female). Measures of naris angle, nasal sill height, nasal valve area relative to internal chamber cross‐sectional area, and relative projection of the inferior and middle turbinates were taken directly on the resulting casts. The relationships between aspects of nasal morphology and turbulent air flow were evaluated by examining the flow regimes (laminar, semiturbulent, or turbulent) at varying flow rates, with the expectation that the greater the development of the proposed turbulence‐enhancing features the slower the flow rate at which flow would shift from one regime to another. Flow characteristics (both flow regimes and principal pathways) were highly variable within our sample. The relative projection of the inferior turbinate was the only variable that significantly affected the flow rate at which flow became turbulent. However, more projecting turbinates appear to laminate flow rather than to induce turbulence. Nostril orientation was moderately correlated with flow dynamics (with more inferiorly directed nares producing turbulence at slower flow rates), but this correlation was not statistically significant. Relative nasal valve area and nasal sill height were unrelated to turbulence in our models. Am. J. Hum. Biol. 16:625–638, 2004. © 2004 Wiley‐Liss, Inc.
Exploring northeast African metric craniofacial variation at the individual level: A comparative study using principal components analysis
Authors: Keita S.O.Y.
Published: October 2004

A principal components analysis was carried out on male crania from the northeast quadrant of Africa and selected European and other African series. Individuals, not predefined groups, were the units of study, while nevertheless keeping group membership in evidence. The first principal component seems to largely capture “size” variation in crania from all of the regions. The same general morphometric trends were found to exist within the African and European crania, although there was some broad separation along a cline. Anatomically, the second principal component captures predominant trends denoting a broader to narrower nasal aperture combined with a similar shape change in the maxilla, an inverse relation between face–base lengths (“projection”) and base breadths, and a decrease in anterior base length relative to base breadth. The third principal component broadly describes trends within Africa and Europe: specifically, a change from a combination of a relatively narrower face and longer vault, to one of a wider face and shorter vault; it shows the northeast quadrant Africans along a cline with the other Africans. Stated in relative terms, the northeastern Africans tend to exhibit narrower bases in relationship to more projecting faces, and broader nasal areas than Europeans, although there is range of variation. Relative to the other African groups, they have narrower nasal areas and narrower faces in relationship to vault length. The crania from the northeast quadrant of Africa collectively demonstrate the greatest pattern of overlap with both Europeans and other Africans. Variation was found to be high in all series but greatest in the African material as a whole. Individuals from different geographical regions frequently plotted near each other, revealing aspects of variation at the level of individuals that is obscured by concentrating on the most distinctive facial traits once used to construct “types.” The high level of African interindividual variation in craniometric pattern is reminiscent of the great level of molecular diversity found in Africa. These results, coupled with those of Y chromosome studies, may help generate hypotheses concerning the length of time over which recent craniometric variation emerged in Africa. Am. J. Hum. Biol. 16:679–689, 2004. © 2004 Wiley‐Liss, Inc.