bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficiency of Shell Waste as a Source of Calcium Carbonate to Produce Calcium Oxide through Calcination Process
Authors: Malau Nya Daniaty , Sianturi Manogari 
Published: April 2024

Aims: The aim of this research is to examine the efficiency of batik shellfish shells as a source of calcium carbonate to produce calcium oxide compounds.
Study Design: The type of research is Experimental.
Place and Duration of Study: Sample: Department of Physics Education, Kristen Indonesia University, Jakarta, between June 2023 and December 2023.
Methodology: There are two stages in the research process, namely the first stage is the preparation and sterilization of batik shellfish shells. The second stage is the calcination of batik shellfish shells to produce CaO Clean the batik shellfish shells using distilled water. Then crush them using a hammer until they become small fragments. Next, dry the small fragments of batik shellfish shells by air-drying them in a closed room. Then, the sample inside the container will undergo calcination process using a furnace/heating furnace with temperature variations of 800°C and 900°C for 8 hours.
Results: The results obtained show the formation of CaO compounds with the characteristic white color of CaO powder and small or fine particle size. The average efficiency of CaO compounds resulting from the calcination of batik shellfish shells at a temperature of 800°C is 61.85%. Meanwhile, the average efficiency of CaO compounds resulting from the calcination of batik shellfish shells at a temperature of 900°C is 55.64%.
Conclusion: The average efficiency of CaO compounds resulting from the calcination of batik shellfish shells at 800°C is greater than the average efficiency of CaO compounds obtained at a calcination temperature of 900°C. This is because the higher the temperature, the purer the CaO compounds produced will be. Therefore, the CaO compound produced from calcination at a temperature of 900°C can be utilized as a source of calcium in various fields.
Androgenic Properties and Subchronic Toxicity of the Aqueous Extract of Pycnanthus angolensis (Welw.) Warb. Wood (Myristicaceae)
Authors: Koularambaye Rodolphe , Béboy Sara Nathalie Edjenguèlè , Jignoua Yannick Sani , Feudjio Alfloditte Flore , Choupo Arnaud , Massah Fabiola Jenny , Pieme Constant Anatole , Moundipa Paul Fewou 
Published: April 2024

Aims: Pycnanthus angolensis (Welw.) Warb. also known as “Etengué” in the Baka language, is a medicinal plant used by the Baka Pygmies of Cameroon to treat erectile dysfunction. This study aimed to evaluate the androgenic activity and subchronic toxicity of the aqueous extract of Pycnanthus angolensis wood.
Study Design: Experimental design.
Place and Duration of Study: Laboratory of Biochemistry, Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, between November 2022 and October 2023.
Methodology: Twenty-five male Wistar strain rats were divided into 5 groups of 5 rats each including a positive control group that received testosterone enanthate (5 mg/kg) intramuscularly once a week; a normal control group that received distilled water (10 ml/kg) and three test groups which received 134 and 267 and 533 mg/kg of the aqueous extract of Pycnanthus angolensis daily per os. On the 29th day, the animals were killed, and several biochemical parameters were assessed for androgenic properties.
Results: At a dose of 134 mg/kg, the extract significantly increased (p<0.05) the levels of testicular cholesterol, testosterone and serum prostatic acid phosphatase activity compared to those of the normal control. A toxicity study showed that at doses of 134 and 267 mg/kg, the extract did not induce any significant variation (p>0.05) in the creatinine level, but a significant reduction (p<0.05) in of aspartate and alanine aminotransferase activities was recorded. Histopathology revealed destruction of testicular spermatozoa at a dose of 533 mg/kg compared to that of the controls.
Conclusion: These results showed that at a dose of 134 mg/kg, the aqueous extract of Pycnanthus angolensis (Welw.) Warb. wood is capable of stimulating the production of androgens and is tolerated by the rat's body. Our results justified the traditional use of this plant for the treatment of male infertility and erectile dysfunction.
Finding the right case: the role of predictive features in memory for aviation accidents
Authors: O'Hare David , Mullen Nadia , Wiggins Mark , Molesworth Brett 
Published: January 2008

AbstractThree experiments examined the role of story structure in memory for written aviation accident reports by both pilots and nonpilots. Accident reports follow a standard format providing setting, complication, decision and outcome information. Following the ‘predictive features’ model, it was hypothesized that expertise would facilitate recall, and that pilots would recall most effectively with the complication feature. Pilot and nonpilot participants read and recalled 4 (Experiment 1) or 8 (Experiment 2) accident reports. With four cases, pilots recalled more than nonpilots, but no difference was found with eight cases. A primacy effect for pattern of recall was found in Experiment 1 with the setting and complication features most effective in triggering case recall. When task difficulty was increased (Experiment 2), the complication feature alone was the most effective. In Experiment 3, we manipulated text structure and found that complication and decision features were better recognized than setting or outcome features by nonpilots. The finding across three studies that the complication feature was consistently the most effective for retrieving aviation accident reports supports the ‘predictive features’ model. Copyright © 2007 John Wiley & Sons, Ltd.
Children's knowledge acquisition through film: influence of programme characteristics
Authors: Michel Eva , Roebers Claudia M. 
Published: January 2008

AbstractSeveral characteristics of educational programmes for children are discussed to influence learning of content. In the present study, positive effects of a preview and inserted summaries in educational films for learning are examined. A total of 127 6‐and 8‐year‐old participating children watched one of the four educational film versions: The original film (without preview and summaries), a version with a preview, with inserted summaries or with a verbal ‘preview’. One week later, children's recollection of facts was tested in a memory interview. Results show that previews and summaries in educational films can enhance learning, and that visual scene repetition appears to further boost knowledge acquisition. Formal and content characteristics of educational programmes are discussed in terms of the underlying mechanisms influencing children's cognitive processing and learning. Copyright © 2008 John Wiley & Sons, Ltd.
Predictive adaptive control of plants with online structural changes based on multiple models
Authors: Lourenço J. M. , Lemos J. M. 
Published: January 2008

AbstractThe objective of this paper is to present a new algorithm to improve the adaptation rate of a predictive adaptive controller. For that sake, the possible plant dynamic outcomes are covered by a bank of models. Each model is used to re‐initialize the adaptive controller every time there is a large change in dynamics. The contribution of the paper consists in the development of a procedure that includes additional models in the bank when found suitable according to defined criteria. The algorithm is demonstrated in a benchmark problem consisting of the position control of two masses coupled by a spring of varying stiffness. Copyright © 2008 John Wiley & Sons, Ltd.
Characterization and astrocytic modulation of system L transporters in brain microvasculature endothelial cells
Authors: Omidi Yadollah , Barar Jaleh , Ahmadian Somaieh , Heidari Hamid Reza , Gumbleton Mark 
Published: January 2008

AbstractBrain trafficking of amino acids is mainly mediated by amino acids transport machineries of the blood–brain barrier (BBB), where astrocytes play a key maintenance role. However, little is known about astrocytes impacts on such transport systems, in particular system L that consists of large and small neutral amino acids (NAAs) transporters, that is, LAT1/4F2hc and LAT2/4F2hc, respectively. In the current investigation, functionality and expression of system L were studied in the immortalized mouse brain microvascular endothelial b.End3 cells cocultured with astrocytes or treated with astrocyte‐conditioned media (ACM). LAT2/4F2hc mediated luminal uptake of L‐phenylalanine and L‐leucine resulted in significantly decreased affinity of system L in b.End3 cells treated with ACM, while LAT2/4F2hc mediated luminal uptake of L‐alanine remained unchanged. Gene expression analysis revealed marked upregulation of LAT1 and 4F2hc, but downregulation of LAT2 in b.End3 cells cultured with ACM. The basal to apical transport of L‐phenylalanine and L‐alanine appeared to be significantly greater than that of the apical to basal direction in b.End3 cells indicating an efflux functionality of system L. No marked influence was observed for transport of L‐phenylalanine in b.End3 cells cocultured with astrocytes, while a slight decrease was seen for L‐alanine in the basal to apical direction. Based on our findings, we propose that system L functions as influx and/or efflux transport machinery displaying a greater propensity for the outward transport of large and small NAAs. Astrocytes appeared to modulate the transcriptic expression and uptake functionalities of system L, but not the transport activities. Copyright © 2008 John Wiley & Sons, Ltd.
Application of different training methodologies for the development of a back propagation artificial neural network retention model in ion chromatography
Authors: Bolanča Tomislav , Cerjan‐Stefanović Štefica , Ukić Šime , Rogošić Marko , Luša Melita 
Published: January 2008

AbstractThe reliability of predicted separations in ion chromatography depends mainly on the accuracy of retention predictions. Any model able to improve this accuracy will yield predicted optimal separations closer to the reality. In this work artificial neural networks were used for retention modeling of void peak, fluoride, chlorite, chloride, chlorate, nitrate and sulfate. In order to increase performance characteristics of the developed model, different training methodologies were applied and discussed. Furthermore, the number of neurons in hidden layer, activation function and number of experimental data used for building the model were optimized in terms of decreasing the experimental effort without disruption of performance characteristics. This resulted in the superior predictive ability of developed retention model (average of relative error is 0.4533%). Copyright © 2008 John Wiley & Sons, Ltd.
Two‐dimensional LC‐MS/MS in detection of peptides in hypothalamus of the rat subjected to hypoxic stress
Authors: Mihailova Albena , Karaszewski Bartosz , Faergestad Ellen Mosleth , Hauser Roman , Nyka Walenty M. , Lundanes Elsa , Greibrokk Tyge 
Published: January 2008

AbstractA capillary 2‐D LC method coupled with IT MS has been used for separation and identification of peptides in rat hypothalamus. Animals of two different age groups (8 and 50 wk) were exposed to two different rates of CO2 in inhaled air to investigate the influence of different hypoxia/hypercapnia levels and their stress‐related factor on the peptide excretion. Peptide compounds were fractionated (strong cation exchange chromatography), trapped, and separated (RP chromatography), and MS/MS mass spectra were used for identification. About 107 peptide compounds were identified and 88 of them were semiquantified. Among the characterized peptides, there were fragments from proteins such as proenkephalin A, proSAAS, prosomatostatin, prooxytocin, vasopressin, etc. Explorative principal component analysis (PCA) combined with hypothesis testing was applied to the obtained data to investigate the impact of age and hypoxic stress factors on the peptide pattern. Twenty‐six peptides revealed significant differences in concentrations between the animal groups influenced by age and influx rate.
Reversible Chain Transfer Catalyzed Polymerizations (RTCPs) of Styrene and Methyl Methacrylate with Phosphorus Catalysts
Authors: Goto Atsushi , Hirai Norihiro , Tsujii Yoshinobu , Fukuda Takeshi 
Published: January 2008

AbstractSummary: Phosphorus compounds were employed as catalysts in Reversible Chain Transfer Catalyzed Polymerization (RTCP), a novel class of living radical polymerization (LRP) which we had recently developed. Low‐polydispersity polystyrene and poly(methyl methacrylate) with predicted molecular weights were obtained with a fairly high conversion in a fairly short time. These catalysts are particularly featured by their high reactivity hence small amounts being required, low toxicity, and low cost. Some phosphorus catalysts used in this work are among the least expensive catalysts/mediators of LRP developed so far.
Kinetics of Controlled/Living Radical Polymerization in Emulsified Systems
Authors: Tobita Hidetaka 
Published: January 2008

AbstractSummary: For the controlled/living radical polymerization (CLRP) in which the active period during the chain formation is extremely small, ϕA < 1, such as the cases of usual SFRP and ATRP, the polymerization rate can be made larger by increasing the average number of monomeric units added during a single active period, $\bar P_{n,SA}$. The $\bar P_{n,SA}$‐value is inversely proportional to the trapping agent concentration [X], and the polymerization rate is controlled by [X]. For small particles, even with a single trapping agent, [X] in the particle could be larger than that in corresponding bulk polymerization, and the polymerization rate decreases with D, where Dp is the particle diameter. On the other hand, for CLRPs whose ϕA‐value is not very much smaller than unity, say ϕA>0.01, such as some of RAFT polymerization systems, the polymerization rate can be made larger by increasing the kinetic chain length for a given initiation frequency. For such reaction systems, the polymerization rate can be enhanced significantly by employing the emulsified polymerization systems.
A Novel GPPS/cis‐SB Blend with High Performance
Authors: Zhu Han , Wu Yi‐Xian , Zhao Jiang‐Wei , Xu Ri‐Wei , Huang Qi‐Gu , Wu Guan‐Ying 
Published: January 2008

AbstractSummary:GPPS/cis‐SB blends with high performance were prepared by adding 3–5 wt.‐% stereoregular butadiene‐styrene block copolymers (cis‐SB) with a highcis‐1,4 configuration of around 97% into general purpose polystyrene (GPPS). The micromorphology of the GPPS/cis‐SB blends was characterized by transmission electron microscopy (TEM). Mechanical properties including tensile and impact properties were studied and the fracture surfaces of tensile and impact test specimens were characterized by scanning electron microscopy (SEM). PB domains of 10–30 nm with a blurry interface were tethered by continuous PS domains. The fracture surface of the tensile test piece of GPPS was relatively smooth while the fractography of patch patterns separated by river patterns was formed when the tensile specimens of GPPS/cis‐SB blends were broken, which may be due to the nanometer‐scale rubber phases with highcis‐1,4 configuration and some partially crystalline PS segments in thecis‐SB block copolymer. It is found that GPPS could be greatly toughened by introduction of a small amount ofcis‐SB and the tensile strength and elongation at break could also be increased.
Landau Mean‐Field Approximation of Percolation in Conductive Polymer Composites
Authors: Song Yihu , Zheng Qiang 
Published: January 2008

AbstractSummary: A novel approach of the percolation behavior in conductive composites was proposed on the basis of Landau mean‐field theory. The percolation transition is treated as a concentration‐derived phase transition of conductive particles from dispersion to flocculation so as to form a dissipative percolating network. A formulation of conductivity as a function of filler volume fraction in the percolation transition region was established, which was validated in high‐density polyethylene/carbon black (HDPE/CB) composites from two different laboratories and also in cured epoxy/CB composites of Fournier et al. At high CB concentrations above the percolation threshold, the conductive behavior in HDPE/CB composites follows the statistical percolation theory.
Novel Amphiphilic Poly(N‐vinylpyrrolidone) Block Copolymer: Aggregative Behavior and Interaction with DNA
Authors: Zhang Lifen , Meng Lingzhi , Lu Xiaoju , Liu Yunhai 
Published: January 2008

AbstractSummary: Novel block copolymers poly(N‐vinylpyrrolidone)‐block‐poly[(tert‐butoxy) carbonyl] tryptophanamido‐N′‐methacryl thiourea (PVP‐b‐PTAM‐I, II and III) were synthesized by atom transfer radical polymerization (ATRP) in DMF using PVP‐Cl as macroinitiator. The structures of the copolymers were characterized by UV‐vis and GPC‐MALLS. The results revealed that the copolymers with controlled molecular weight and relatively low polydispersity (PDI < 1.34) were obtained through ATRP. By means of dynamic light scattering (DLS) and transmission electron microscopy (TEM), we demonstrated that copolymer PVP‐b‐PTAM self‐aggregated to form spherical micelles in aqueous solution and the size of the micelles increased with increasing hydrophobic contents. The interaction of PVP‐b‐PTAM with DNA was explored using ethidium bromide (EB) quenching experiments. The interaction between PVP‐b‐PTAM and DNA markedly depended on both the copolymer concentration and composition. The PVP‐b‐PTAM‐II and III with higher hydrophobic contents exhibited highly complexed DNA ability at low copolymer concentration, such as 0.017 mg/mL, relative to PVP‐b‐PTAM‐I. As the copolymer concentration further increased for PVP‐b‐PTAM‐II and III, they first exhibited a sharply decreased affinity for DNA and then kept steady. The interaction mechanism between the amphiphilic copolymers and the EB‐DNA complex was discussed in detail.
Interaction of elementary waves on a boundary for a hyperbolic system of conservation laws
Authors: Yao Aidi , Sheng Wancheng 
Published: January 2008

AbstractIn this paper, we study the interaction of elementary waves including delta‐shock waves on a boundary for a hyperbolic system of conservation laws. A boundary entropy condition is derived, thanks to the results of Dubois and Le Floch (J. Differ. Equations 1988; 71:93–122) by taking a suitable entropy–flux pair. We obtain the solutions of the initial‐boundary value problem for the system constructively, in which initial‐boundary data are piecewise constant states. Copyright © 2008 John Wiley & Sons, Ltd.
Error estimates of mixed methods for optimal control problems governed by parabolic equations
Authors: Xing Xiaoqing , Chen Yanping 
Published: January 2008

AbstractIn this paper, we investigate the error estimates for the solutions of parabolic optimal control problem by mixed finite element methods. The state and co‐state are approximated by the lowest‐order Raviart–Thomas mixed finite element spaces, and the control is approximated by piecewise constant functions. The convergence for the states, co‐states and the control is demonstrated. Copyright © 2008 John Wiley & Sons, Ltd.
Treatment with inhaled corticosteroids in asthma is too often discontinued
Authors: Breekveldt‐Postma Nancy S. , Koerselman Jeroen , Erkens Joëlle A. , van der Molen Thys , Lammers Jan‐Willem J. , Herings Ron M. C. ,   for the CAMERA Study Group
Published: January 2008

AbstractPurposeTo study persistence with inhaled corticosteroids (ICS) and its determinants in asthma‐patients.MethodsFrom the PHARMO database, asthma‐patients (age < 35 years) with a first dispensing for ICS in 1999–2002 and ≥ 2 dispensings in the first year were included. Persistence during the first year was defined as the number of days from start to time of first failure to continue renewal of the initial ICS. Potential determinants of persistence were assessed at ICS‐start and 1 year before.ResultsThe study‐cohort included 5563 new users of single ICS and 297 of fixed‐combined ICS. Less than 10% of patients using single ICS and 15% of patients using fixed‐combined ICS were persistent at 1 year. Similar persistence‐rates were observed when stratified for age (children/adolescents: 0–18 years and adults: 19–34 years). Increased persistence with single ICS was observed with the type of ICS (budesonide), prescriber (specialist), prior use of long‐acting beta‐agonists, previous hospitalization for asthma, metered‐dose inhaler, low starting‐dose and once‐daily dosing regimen at start. Persistence with fixed combined ICS‐treatment increased with younger age and was decreased in patients having high starting‐dose of ICS and prior use of antibiotics.ConclusionNew users of both single and fixed combined ICS have alarming low persistence rates with ICS‐treatment in the first year of follow‐up. Persistence was mainly related to patient factors, such as severity of disease, and to treatment‐related factors, such as once‐daily dosing frequency. Copyright © 2008 John Wiley & Sons, Ltd.
Technologies and methods for sample pretreatment in efficient proteome and peptidome analysis
Authors: Jiang Xiaogang , Ye Mingliang , Zou Hanfa 
Published: January 2008

AbstractAlthough great progresses have been made in proteomics during the last decade, proteomics is still in its infancy. Extreme complexity of proteome sample and large dynamic range of protein abundance overwhelm the capability of all currently available analytical platforms. Sample pretreatment is a good approach to reduce the complexity of proteome sample and decrease the dynamic range. In this article, we present an overview of different technologies and methods for sample pretreatment in efficient proteome and peptidome analysis. Methods for isolation of rare amino acid‐containing peptides, terminal peptides, PTM peptides and endogenous peptides are reviewed. In addition, two automated sample pretreatment technologies, i.e. automated sample injection and on‐line digestion, are also covered.
Target coatings and desorption surfaces in biomolecular MALDI‐MS
Authors: König Simone 
Published: January 2008

AbstractMALDI‐MS is an extremely flexible technique and can be synergistically used in conjunction with established bioanalytical methods such as PAGE or SPR. To that end, slight modifications on the sample target plate may be necessary. Those can involve the use of hydrophobic coatings for improved sample deposition and desalting or that of sensor surfaces for on‐target bioaffinity experiments. In particular the latter have evolved considerably over the past years. Surface coatings using polysaccharide or polycarboxylate hydrogels were adopted from unrelated techniques and they proved very suitable for bioaffinity MS. The developments concerning target modification and derivatization are reviewed.
Matrix‐assisted laser desorption/ionization signal enhancement of peptides by picolinamidination of amino groups
Authors: Kim Jong‐Seo , Kim Ji‐Hyun , Kim Hie‐Joon 
Published: January 2008

AbstractPicolinamidination of amino groups in peptides was carried out using ethyl picolinimidate tetrafluoroborate synthesized from picolinamide and triethyloxonium tetrafluoroborate. The N‐terminal amino group as well as the ε‐amino group of lysine were derivatized. The matrix‐assisted laser desorption/ionization (MALDI) signal of a peptide was enhanced 20–35‐fold upon picolinamidination depending on the number of amino groups derivatized. The signal enhancement effect is much higher than that of acetamidination or guanidination previously reported. Improved protein identification by mass mapping of the derivatized peptides was demonstrated. Copyright © 2008 John Wiley & Sons, Ltd.