bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microwave dielectric properties of polybutylene terephtalate (PBT) with carbon black particles
Authors: Costa L. C. , Devesa S. , André P. , Henry F. 
Published: May 2005

AbstractThe synthesis of composites based on polymers containing carbon as additives is rather relevant because it has been found that applications in several industries are increasing, particularly due to their unusual mechanical and electrical properties. By choosing the adequate doping concentrations, we can precisely control the electrical properties in the microwave frequencies, in order to tailor the desired behavior. In this study, we present the results of the complex‐permittivity measurements, ϵ* = ϵ′ − í ϵ″, at 2.7, 5, and 12.8 GHz, on polybutylene terephtalate (PBT), with different concentration of black carbon particles, using the resonant‐cavity method. Measuring the shift in the resonant frequency of the cavity, Δf, caused by the insertion of the sample, we can calculate to the real part of the complex permittivity, ϵ′, while the measure of the change in the inverse of the quality factor of the cavity, Δ(1/Q), allow us to calculate the imaginary part, ϵ″. Maxwell–Wagner–Sillars (MWS) and Looyenga mixture laws are applied to the obtained results. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 61–63, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20901
A 5‐GHz injection‐locked phase‐locked loop
Authors: Plessas Fotis , Kalivas Grigorios 
Published: May 2005

AbstractIn this paper, we introduce a 5‐GHz injection‐locked phase‐locked loop (ILPLL). A new method is presented for accurate analysis of the phase‐noise performance of the proposed system. Furthermore, comparison with other phase‐noise‐estimation techniques demonstrates that our method provides an accurate characterization of any ILPLL topology. The theoretical and calculation results show an improved performance for phase noise, locking range, and power consumption compared to conventional phase‐locked loops (PLLs) and injection‐locked oscillators (ILOs). Furthermore, we demonstrate the pulling behavior of the injected oscillator and examine the obtained results. To verify the presented analysis, a 5‐GHz prototype has been implemented, which achieves −119‐dBc/Hz at 100‐KHz frequency offset, producing +4.5 dBm of output power and consuming 9 mA at 3 V. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 80–84, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20907
InGaP/GaAs HBT power amplifier with CMRC structure
Authors: Poek C. K. , Yan B. P. , Yang E. S. 
Published: May 2005

AbstractAn InGaP/GaAs heterojunction bipolar transistor (HBT) power amplifier is developed for WCDMA user equipment, specifically, band‐1‐power class‐2 application. The HBT power amplifier demonstrates maximum output power Poutof 29.4 dBm and power‐added efficiency (PAE) of 48% at a frequency of 1.95 GHz. When operated according to the WCDMA standard, it achieves Poutof 27 dBm and PAE of 32.4%. The adjacent channel leakage power ratio (ACLR) is −33 dBc. A compact microstrip resonant cell (CMRC) circuit is implemented on the HBT amplifier in order to further improve the PAE, ACLR, and IM3 performances. This results in improvements of 8 dB and 6% for the ACLR and PAE, respectively. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 84–88, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20908
Two‐stage S‐band erbium‐doped fiber amplifier using a depressed‐cladding fiber
Authors: Harun S. W. , Saat N. K. , Ahmad H. 
Published: May 2005

AbstractA two‐stage short‐wavelength‐band erbium‐doped fiber amplifier (S‐band EDFA) is demonstrated using a depressed‐cladding erbium‐doped fiber (EDF). The EDF has a fundamental‐mode cutoff wavelength of about 1525 nm in order to suppress amplified spontaneous emission at the longer wavelength. The highest gain curve is obtained by setting the first‐ and second‐stage pumps at 85 and 190 mW, respectively, where the unsaturated gains are obtained at about 28 dB. The gain was limited by the 12‐dBm saturation power of the amplifier. The unsaturated noise figure ranged from 8.5 to 9.3 dB for all pump combinations tested. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 92–94, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20910
Skeletal muscle involvement in human immunodeficiency virus (HIV)–infected patients in the era of highly active antiretroviral therapy (HAART)
Authors: Authier François‐Jérôme , Chariot Patrick , Gherardi Romain K. 
Published: May 2005

AbstractSkeletal muscle involvement can occur at all stages of human immunodeficiency virus (HIV) infection, and may represent the first manifestation of the disease. Myopathies in HIV‐infected patients are classified as follows: (1) HIV‐associated myopathies and related conditions, including HIV polymyositis, inclusion‐body myositis, nemaline myopathy, diffuse infiltrative lymphocytosis syndrome (DILS), HIV‐wasting syndrome, vasculitic processes, myasthenic syndromes, and chronic fatigue; (2) muscle complications of antiretroviral therapy, including zidovudine and toxic mitochondrial myopathies related to other nucleoside‐analogue reverse‐transcriptase inhibitors (NRTIs), HIV‐associated lipodystrophy syndrome, and immune restoration syndrome related to highly active antiretroviral therapy (HAART); (3) opportunistic infections and tumor infiltrations of skeletal muscle; and (4) rhabdomyolysis. Introduction of HAART has dramatically modified the natural history of HIV disease by controlling viral replication, but, in turn, lengthening of the survival of HIV‐infected individuals has been associated with an increasing prevalence of iatrogenic conditions. Muscle Nerve, 2005
Compatibilizer‐induced microstructural changes in poly(trimethylene terephthalate)/EPDM blends studied by the positron annihilation lifetime technique and differential scanning calorimetry
Authors: Ravikumar HB , Ranganathaiah C 
Published: May 2005

AbstractBlends of poly(trimethylene terephthalate) (PTT) and ethylene propylene diene monomer (EPDM) with and without the compatibilizer poly (EPM‐graft‐MA) were investigated by positron annihilation lifetime spectroscopy (PALS) and differential scanning calorimetric (DSC) measurements. The DSC results for the blend with 50/50 composition revealed two glass transition temperatures, indicating a two‐phase system. In the presence of compatibilizer, the two glass transition temperatures shifts towards each other, suggesting an increased interaction between the blend components. The PALS results for the blends without compatibilizer showed an increase in free volume hole size and concentration with increasing EPDM content in the blend, suggesting the coalescence of free volumes of EPDM with the PTT to some extent, but the phase‐separation behaviour continued. The free volume of these blends exhibited positive deviation from the known free volume linear additivity rule. However, poly(EPM‐graft‐MA) compatibilized blends of PTT/EPDM had a noticeable decrease in the free volume parameters, which was clearly due to the compatibilizing effect through increased interaction between blend components. Copyright © 2005 Society of Chemical Industry
Markovian approach of the electron localization functions
Authors: Putz Mihai V. 
Published: May 2005

AbstractBy combining the path integral description of Markovian processes in terms of conditional probabilities with the catastrophe topological concepts alternative electron localization classes of functions (ELFs) are formulated, consistent with the Heisenberg and Pauli principles, complementing and augmenting the previous work of Becke and Edgecombe. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Analytical second derivatives in the Amsterdam density functional package
Authors: Wolff Stephen K. 
Published: May 2005

AbstractRecently, analytical second derivatives with respect to nuclear coordinates have been implemented in the Amsterdam density functional (ADF) package. This article presents the detailed formalism of that implementation. Calculations on small molecules such as methane show good agreement between the analytical and numerical frequencies. Calculations on benzene and larger molecules show that the analytical second derivatives code is 2 to 3 times faster than the numerical. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Using probabilistic model checking for dynamic power management
Authors: Norman Gethin , Parker David , Kwiatkowska Marta , Shukla Sandeep , Gupta Rajesh 
Published: May 2005

Abstract
Dynamic power management (DPM) refers to the use of runtime strategies in order to achieve a tradeoff between the performance and power consumption of a system and its components. We present an approach to analysing stochastic DPM strategies using probabilistic model checking as the formal framework. This is a novel application of probabilistic model checking to the area of system design. This approach allows us to obtain performance measures of strategies by automated analytical means without expensive simulations. Moreover, one can formally establish various probabilistically quantified properties pertaining to buffer sizes, delays, energy usage etc., for each derived strategy.
Social and psychological characteristics of Greek secondary school students with learning difficulties
Authors: Zafiriadis Kiriakos , Livaditis Miltos , Xenitidis Kiriakos , Diamanti Miranta , Tsatalmpasidou Evgenia , Sigalas Ioannis , Polemikos Nikitas 
Published: May 2005

AbstractIn Greece there is an almost total lack of special education after the primary school (6th grade). This is a descriptive study that aimed to examine social, academic and psychological characteristics of secondary school students with a history of special placement during primary school. It compared 86 students with a placement (group A) with their 1284 schoolmates with no such placement history (group B) with respect to scores on School Adjustment Scale, Academic Motivation Self‐Rating Inventory and Youth Self‐Report. Group A presented more family social, academic and psychological problems such as: One‐parent family, lower socioeconomic status, poor adjustment, low motivation and (especially for boys) high internalizing and externalizing scores. The high rates of failure and dropout of these students indicate that in Greece there is a need to set up appropriate services to help secondary school students with learning difficulties.
Patient's Education by Nurse: What We Really do Achieve?
Authors: González Beatriz , Lupón Josep , Herreros Joan , Urrutia Agustín , Altimir Salvador , Coll Ramon , Prats Montserrat , Valle Vicente 
Published: May 2005

Aim: To evaluate what is really achieved with nurse education in an outpatient heart failure population. Method: The answers obtained in a nurse questionnaire performed at the first visit to the Unit and at 1 year of follow-up were compared. The questionnaire was addressed to know how compliant patients were and how much they knew about their disease and their treatment. Results: Two hundred and ninety eight patients (219 men and 79 women) were evaluated. Baseline mean age was 65 years (35–86). At first visit only 30% knew and understood the performance of the heart; 56% at 1 year ( p < 0.001). Only 28% initially understood the disease; 55% at follow-up ( p < 0.001). Awareness of more than 3 worsening signs increased from 66.5% to 86.5% ( p < 0.001). Knowledge of the names of all the pills they were receiving increased from 33% to 44% ( p < 0.001), of the action of these pills from 24% to 44% ( p < 0.001), and of how to use nitroglycerine among patients with ischemic heart disease from 87% to 96% ( p < 0.001). Initially 63% monitored their weight only at the medical visit and 21% monitored it at least once a week; at 1 year these percentages were 16% and 39% respectively ( p < 0.001). At baseline 45% checked blood pressure only at the medical visit and 28.5% checked it at least once a week; at 1 year these percentages were 12% and 43% ( p < 0.001). Whereas no significant differences were found in sodium restricted diet compliance, exercise performance increased slightly although statistically significantly ( p = 0.01). The great majority of patients never or only very rarely smoked or drunk alcoholic beverages, both at first visit and at 1 year, although both habits increased slightly during follow-up. No significant differences in treatment compliance (92% vs. 88% were taking all the medications prescribed) were found. Conclusion: Nurse-guided education has changed self-care behaviour of patients with heart failure in several important aspects, as weight and blood monitoring, and has increased their knowledge and understanding of the disease and treatment. However, these improvements have not been reflected in a better compliance of treatment and sodium restricted diet. Such aspects need more and more work to obtain better results.
A study of the effect of exposure in the reticulo-rumen of the cow on the strength of cotton, grass, hay and straw
Authors: Evans E. W. , Burnett J. , Bines J. A. 
Published: May 2005

1. Changes in strength of cotton, Italian ryegrass leaf, hay stem and barley-straw stem on immersion in the contents of the reticulo-rumen, at two sites in the rumen and at one site in the reticulum, for periods of up to 56 h were measured using a cow on a hay diet. Specimens of the fibrous materials were immersed in the rumen digesta in such a way that they were not damaged by agitation or by rumination.2. Load-to-fracture and elongation were measured on a machine using a constant-speed cross-head at a strain of about 10−3/s. The ratio strength:density (breaking load/mass per unit length) was determined.3. Leaf of Italian ryegrass and stem of hay and of barley straw had strengths of about 37, 150 and 210 MN/m2. They lost strength at different rates when immersed in the rumen digesta, the times to half strength being in the ratio grass: hay: straw = 1:1.9:3.8. The similarity of this ratio to that for total time for eating and ruminating as given by Balch (1969), namely 1:2.0:3.5, for similar materials was noted.
Ruminal bioshynthesis of aromatic amino acids from arylacetic acids, glucose, shikimic acid and phenol
Authors: Kristensen S. 
Published: May 2005

1. Ruminal metabolism of labelled phenylacetic acid, 4-hydroxyphenylacetic acid, indole-3-acetic acid, glucose, shikimic acid, phenol, and serine was studied in vitro by short-term incubation with special reference to incorporation rates into aromatic amino acids.2. Earlier reports on reductive carboxylation of phenylacetic acid and indole-3-acetic acid in the rumen were confirmed and the formation of tyrosine from 4-hydroxyphenylacetic acid was demonstrated for the first time.3. The amount of phenylalanine synthesized from phenylacetic acid was estimated to be 2 mg/1 rumen contents per 24 h, whereas the amount synthesized from glucose might be eight times as great, depending on diet.4. Shikimic acid was a poor precursor of the aromatic amino acids, presumably owing to its slow entry into rumen bacteria.5. A slow conversion of phenol into tyrosine was observed.
Vitamin B12absorption in megaloblastic anaemia
Authors: Senewiratne B. , Hettiarachchi J. , Senewiratne Kamalini 
Published: May 2005

1. The response to cyanocobalamin and folic acid therapy was studied in forty-seven subjects with severe nutritional megaloblastic anaemia; twenty-five were vitamin B12deficient and, of these, ten were also folic acid deficient.2. In twenty-four of the subjects, absorption of orally administered cyanocobalamin was normal, and there was a haematological response to small doses of orally administered cyanocobalamin, indicating adequate absorption. In one subject there was impaired cyanocobalamin absorption although free gastric hydrochloric acid was present.3. The findings indicate that the absorptive function of the small intestine was unimpaired, with one exception, although there was a possible defect in nucleoprotein synthesis associated with a lack of vitamin B12and folic acid. Addisonian pernicious anaemia was not found in any of the subjects.
Jejunal absorption rates of glucose, glycine and glycylglycine in Zambian African adults with malnutrition
Authors: Cook G. C. 
Published: May 2005

1. Absorption rates of glucose (from a 200 mM solution), glycine (from a 100 mM solution), and glycylglycine (from a 50 mM solution) have been estimated in six Zambian African adults with clinical evidence of malnutrition. A double-lumen tube technique was used to determine absorption rates from a 300 mm section of jejunum in vivo.2. Two of the subjects had ileal tuberculosis and Kaposi's sarcoma respectively. A third probably had abdominal tuberculosis. Three of them had pellagra. Mean serum albumin concentration was 24 (14–43) g/l. Absorption rates have been compared with those in Zambian Africans (control subjects), previously studied, who had no clinical evidence of malnutrition, systemic infection or of gastrointestinal disease.3. Mean glucose, glycine and glycylglycine absorption rates in the malnourished subjects were not significantly different from those in the control subjects. Mean net water absorption rate from the glucose solution was similar in the malnourished subjects and controls; during the glycine and glycylglycine perfusions the mean net absorption rate was, however, significantly lower in the malnourished subjects (P < 0.01 and P < 0.05 respectively); mean net water transfer during the glycine perfusions was towards the jejunal lumen in the malnourished subjects. One subject with pellagra had an abnormal excretion of D-xylose after a 25 g oral load; all other tests were normal.4. It seems probable that malnutrition must be very severe, with jejunal mucosal abnormalities, before absorption rates of glucose, glycine and glycylglycine are significantly altered. The present study does not support the view that subclinical malnutrition is important in producing malabsorption of dietary components in Zambian African subjects. Systemic bacterial infections, and raised serum γ-globulin and immunoglobulin IgG concentrations have previously been associated with an impairment of glucose absorption rate in Zambian African subjects; those factors seem much more likely than subclinical malnutrition to be relevant, in the context of absorption, in the pathogenesis of overt malnutrition.
Effects of dietary deficiencies of protein and retinol on the plasma level of retinol-binding protein in the rat
Authors: Muhilal H. , Glover J. 
Published: May 2005

1. The plasma concentration of retinol-binding holoprotein (holo-RBP) in rats given retinol-sufficient diets containing 50 g soya-bean protein/kg was 90 % of the concentration found in controls given 200 g soya-bean protein/kg, whereas in rats given 50 g rice protein/kg it was only 68 % of the control value. Plasma albumin concentrations in the low-protein groups were lower by 20–25 %.2. The rats given retinol-deficient diets, whose plasma levels of holo-RBP were reduced almost to zero after 5–8 weeks, were given 1·5 mg retinol/kg body-weight. Changes in plasma holo-RBP were measured for 7 d. The rapid rise in the latter to a peak above normal control levels within 1·5–2 h indicated that a pool of the apoprotein had accumulated in the liver during the period of deficiency and that retinol was necessary for its release.3. The maximum value reached in the groups of rats given the rice-protein diet was smaller than the values for the groups given the soya-bean-protein diets, reflecting a reduced rate of synthesis of the carrier protein in the livers of those groups.4. The administration of 100 g casein/kg diet to the rats receiving only 50 g rice-protein/kg immediately stimulated the synthesis of the carrier protein which was released into plasma, reaching a peak after 24 h before settling down after 3–4 d to the steady-state level expected for normal well-nourished controls.5. The half-life for excess holo-RBP released into plasma of rats receiving a normal level of good-quality protein was 7 h, where it was 14 h for the groups of low-protein diets.
Branched-chain amino acid oxidation in relation to catabolic enzyme activities in rats given aprotein-free diet at different stages of development
Authors: Sketcher R. D. , James W. P. T. 
Published: May 2005

1. The capacity of animals to conserve branched-chain amino acids was assessed during 3 weeks on a protein-free (PF) diet in groups of female rats at three stages of development, i.e. at weaning (35 g), in a period of rapid growth (85 g) and at maturity (200 g).2. Leucine and valine oxidation was assessed by monitoring the evolution of14CO2from a tracer dose of the [1-14C]-labelled L-amino acid given intragastrically. Activities of the L-leucine:2-ketoglutarate aminotransferase (EC2.6.1.6) and α-keto acid dehydrogenase enzymes in leucine and valine metabolism were also determined in muscle and liver at weekly intervals.3. All three groups of rats given a normal protein intake excreted the same proportion of the dose of labelled leucine and valine. In rats given PF diet there was a consistent reduction in14CO2output from both L-[1-14C]leucine and L-[1-14C]valine, but valine was not conserved as efficiently as leucine.4. Muscle dehydrogenase responded to a PF diet in all three groups of rats, but the most marked changes occurred in the youngest group. In addition, there was a decrease in hepatic dehydrogenase activities for leucine and valine catabolism in the weanling group; in older animals there was little change in the α-keto-isovalerate, but a consistent decrease in the activity of the α-keto-isocaproic acid dehydrogenase. The difference in the responsiveness of the dehydrogenases, therefore, matched the difference between leucine and valine oxidation rates in vivo.5. Weanling animals responded rather more efficiently than the older animals to the need to conserve amino acids and there was no evidence of a poorly developed system for adapting to PF intake at this early stage of development.6. Despite reduced catabolism of the amino acids, aminotransferase activities in liver and muscle rose in the first 1–2 weeks on a PF regimen. Aminotransferase activity as such is unlikely to control acid oxidation.
Digestion of dry and high-moisture maize diets in the stomach of the pig
Authors: Holmes J. H. G. , Bayley H. S. , Horney F. D. 
Published: May 2005

1. Pigs were fitted with re-entrant duodenal cannulas anterior to the pancreatic duct, and total collections of digesta were made for 12 h periods.2. Maize–soya-bean diets were made from maize which had been harvested with a dry-matter content of 770 g/kg and either dried, preserved with acetic or propionic acid or ensiled naturally. The pigs received two meals of these diets/d at 12 h intervals, and the amount of digesta flowing through their cannulas was measured.3. Between 4.5 and 5.25 l of digesta flowed through the cannulas in the 12 h collection period, 0.9 of the total 12 h flow passed through the cannulas in the first 9 h with the dry-maize diet and 0.8 with the acid-treated-maize diets.4. The mean total dry matter intake was 358 g/meal, and 304 g dry matter passed through the duodenal cannulas in the 12 h collection period. The corresponding intake and flow of nitrogen (g/12 h) was 11.1 and 9.6, and for chromic oxide 1.13 and 0.94.5. The pigs consumed 205 g starch (total α-linked glucose polymers)/meal, and 1.5 g free glucose/meal. Only 110 g starch and 4.1 g free glucose reached the duodenal cannulas, suggesting that digestion and absorption of up to 92 g glucose had taken place anterior to the pancreatic ducts.