bluuebunny/crossref_metadata_2025 huggingface dataset:
On teaching finite element method in plasticity with Mathematica
Authors: Jiang Yansheng , Wang Chong
Published: April 2008

To help students to understand how finite element methods (FEM) deal with the plasticity, we have developed a FEM program by using Mathematica, a symbolic algebra system. The program is compact and of very good readability. Its use in our teaching the theory of plasticity has led to positive results. © 2008 Wiley Periodicals, Inc. Comput Appl Eng Educ 16: 233–242, 2008; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae20135
CAL2: Computer aided learning in computer architecture laboratory
Authors: Djordjevic Jovan , Nikolic Bosko , Borozan Tanja , Milenković Aleksandar
Published: April 2008

Computer architecture courses are crucial core courses in computer engineering, electrical engineering, and computer science programs. Dramatic changes in technology, markets, and computer applications create a quite unique and challenging arena for computer architecture instructors and students. The goal is to provide learning environments that will offer hands‐on experience and nurture rapid learning, yet be intuitive and interesting to students. In this paper we discuss the challenges in teaching such courses and present a very flexible educational environment for teaching and learning of computer architecture and organization (CAL2). The CAL2 encompasses a number of software tools that are used both in laboratory settings and at home during self‐study. The CAL2 allows students to write and execute their own assembly language programs, ‘experience’ program execution through graphic simulation and animation, inspect implementation details down to the register transfer level, display timing diagrams, and test their knowledge. In addition, the CAL2 offers a number of features that help instructors define, configure, manage, and administer the laboratory exercises. © 2008 Wiley Periodicals, Inc. Comput Appl Eng Educ 16: 172–188, 2008; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae20141
Sorptive Potential of Beach Sand to Remove Ni(II) Ions: An Equilibrium Isotherm Study
Authors: Haider Taqvi Syed Igleem , Hasany Syed Moosa , Bhanger Mohammad Igbal
Published: April 2008

The potential to remove Ni(II) ions from aqueous solutions using sea beach sand, a carbonate‐quartz mineral, was thoroughly investigated. The effects of relevant parameters such as solution pH, adsorbent dose, metal ions concentration, and temperature on Ni(II) sorption onto beach sand were examined. The sorption data followed the Langmuir, Freundlich and Dubinin‐Radushkevich (D‐R) isotherms. The adsorption was endothermic in nature at ambient temperature and the computation of the parameters, ΔH, ΔS and ΔG indicated the interactions between sorbate and sorbent to be thermodynamically favorable. Equilibrium was achieved very quickly within 30 min of shaking. A pseudo‐first order Lagergren equation was used to test the adsorption kinetics. Other kinetic models, e. g., the Morris‐Weber and Reichenberg equations, were used to calculate the rate constant of intraparticle diffusion and the fate of the diffusion process, respectively. The influence of some of the common cations and anions were also a subject of this study.
Estimation of the Amount of Suspended Sediment in the Tigris River using Artificial Neural Networks
Authors: Hamidi Nizamettin , Kayaalp Necati
Published: April 2008

The amount of sediment should be taken into consideration in the planning of water structures for efficient use of limited water resources. It is important to estimate the amount of sediment for the successful operation of these structures in their future performances. Such estimations can be achieved by Artificial Neural Network (ANNs) with low error percentages as seen in many other disciplines. These networks also enable the modeling of nonlinear relationships between the parameters affecting the event. The purpose of this research is to establish models for sediment amounts in the Tigris River at the Diyarbakir measurement station in Turkey. Rainfall, temperature and discharge are taken as independent variables in the models, whereas sediment is taken as the dependent variable. Fourteen different models are generated using ANNs and Regression Analysis (RA). The results are compared with each other and with the observed data. The relative error and determination coefficient are used as comparison criteria. It is concluded that due to their nonlinear modeling capability, ANNs give better results than RA.
Treatment of Refractory Organics Contained in Actual Agro‐Industrial Wastewaters by UV/H2O2
Authors: Bedoui Ahmed , Sindi Kaiis , Bensalah Nasr
Published: April 2008

In this work, the treatment of actual agro‐industrial wastewaters (IWW) by a UV/H2O2 process has been investigated. The aqueous wastes were received from industrial olive oil mills and then treated by laboratory scale physicochemical methods, i. e., coagulation using ferrous and aluminum sulfate, decantation, filtration and adsorption on activated carbon. These wastes are brown colored effluents and have a residual chemical oxygen demand (COD) in the range of 1800 to 3500 mgO2 L–1, which cannot be further eliminated with physicochemical processes. The UV/H2O2 treatments were carried out under monochromatic irradiation at 254 nm using a thermostated reactor equipped with a mercury vapor lamp located in an axial position. The effects of initial H2O2 concentration, initial COD, pH and temperature have been studied in order to determine the optimum conditions for maximum color and COD removals. The experimental results reveal the suitability of the UV/H2O2 process for both removal of high levels of COD and effectively decolorizing the solution. In particular, 95% of color removal and 90% of COD removal were obtained under conditions of pH = 5 and 32°C using 2.75 g H2O2 g–1 COD L–1 during 6 h of UV‐irradiation. The treatment is unaffected by pH over the range 2 to 9. In addition, the COD removal is improved by increasing the temperature, whereas the color removal has not been affected by this parameter. The results show that the hydroxyl radicals generated from the catalytic decomposition of H2O2 by UV‐irradiation of the solution could be successfully used to mineralize the organics contained in IWW. The mineralization of the organics seems to occur in three main sequential steps: the first is the rapid decomposition of tannins leading to aromatic compounds, which are confirmed by the decolorization of the IWW; the second step corresponds to the oxidation of aromatics leading to aliphatic intermediates, which occurs by the cleavage of an aromatic ring, and is established by the removal of aromatics, and the final step is the slow oxidation of the aliphatic intermediates, which is measured by the COD removal.
Sustainable Chemical Technologies in Production of Clean Fuels from Fossil Fuels
Authors: Taniewski Marian
Published: April 2008

Some aspects of the present and the possible future role of sustainable chemical technologies in the production of clean liquid and gaseous fuels from fossil fuels are discussed. The state‐of‐the‐art and the vision of possible sources and alternative routes which may lead to clean fuels from fossil fuels due to the progress in crude oil, natural gas and coal processing are briefly presented. The possible future role of the Fischer‐Tropsch synthesis, methanol synthesis, dimethylether synthesis, and a group of methanol transformation processes is also discussed.
Conformationally Restricted Hydantoin‐Based Peptidomimetics as Inhibitors of Caspase‐3 with Basic Groups Allowed at the S3 Enzyme Subsite
Authors: Vázquez Jesús , García‐Jareño Alicia , Mondragón Laura , Rubio‐Martinez Jaime , Pérez‐Payá Enrique , Albericio Fernando
Published: April 2008

By using a combination of molecular modeling, combinatorial chemistry, and biological essays, novel scaffold molecules for the inhibition of caspase‐3 have been developed. These compounds have an overall attenuated negative charge and show similar IC50 values for both recombinant and human endogenous caspase‐3. This might provide the basis for a novel strategy for the discovery of potent and more druglike inhibitors of caspase‐3.
Development of enteric and vagal innervation of the zebrafish (Danio rerio) gut
Authors: Olsson Catharina , Holmberg Anna , Holmgren Susanne
Published: April 2008

The autonomic nervous system develops following migration and differentiation of precursor cells originating in the neural crest. Using immunohistochemistry on intact zebrafish embryos and larvae we followed the development of the intrinsic enteric and extrinsic vagal innervation of the gut. At 3 days postfertilization (dpf), enteric nerve cell bodies and fibers were seen mainly in the middle and distal intestine, while the innervation of the proximal intestine was scarcer. The number of fibers and cell bodies gradually increased, although a large intraindividual variation was seen in the timing (but not the order) of development. At 11–13 dpf most of the proximal intestine received a similar degree of innervation as the rest of the gut. The main intestinal branches of the vagus were similarly often already well developed at 3 dpf, entering the gut at the transition between the proximal and middle intestine and projecting posteriorly along the length of the gut. Subsequently, fibers branching off the vagus innervated all regions of the gut. The presence of several putative enteric neurotransmitters was suggested by using markers for neurokinin A (NKA), pituitary adenylate cyclase‐activating polypeptide (PACAP), vasoactive intestinal polypeptide (VIP), nitric oxide, serotonin (5‐hydroxytryptamine, 5‐HT), and calcitonin gene‐related peptide (CGRP). The present results corroborate the belief that the enteric innervation is well developed before the onset of feeding (normally occurring around 5–6 dpf). Further, the more detailed picture of how development proceeds at stages previously not examined suggests a correlation between increasing innervation and more regular and elaborated motility patterns. J. Comp. Neurol. 508:756–770, 2008. © 2008 Wiley‐Liss, Inc.
Effects of early deprivation and maternal separation on pup‐directed behavior and HPA axis measures in the juvenile female rat
Authors: Rees Stephanie L. , Akbari Emis , Steiner Meir , Fleming Alison S.
Published: April 2008

Juvenile female rats show maternal‐like behavior toward pups. The purpose of the following experiment was to investigate whether the HPA axis, through the use of early separation manipulations that alter HPA functioning in rats, plays a role in the juvenile response to foster pups. Female rats were early deprived or maternally separated for 5 hours daily from PND 2 to 14 and compared to animal facility‐reared rats. Deprivation or separation increased CRH‐R1 IR in the juvenile PVN, but had no other effects on other HPA measures or on maternal behavior. Pup‐exposure during the juvenile period blunted corticosterone levels after acute and repeated pup‐exposures when compared to exposure to novelty and conspecifics respectively. Repeated exposures to pups also increased CRH‐R1 IR relative to isolation during the juvenile period. Overall, the data suggest that although pup‐exposure affects corticosterone levels, the HPA axis does not relate to juvenile maternal behavior in the present experiments. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 315–321, 2008.
Isolation and the timing of mammary gland development, gonadarche, and ovarian senescence: Implications for mammary tumor burden
Authors: Hermes Gretchen L. , McClintock Martha K.
Published: April 2008

In this study of Norway rats, we hypothesized that lifelong psychosocial experiences, social isolation or group living, trigger different developmental trajectories in the ovarian system, contributing to predisease pathways for spontaneous mammary tumors. Epidemiological studies indicate that early puberty and delayed menopause are risk factors for breast cancer. To that end, we took a cross‐sectional, prospective approach and examined the ovarian system at two developmental points, young adulthood and middle age. We assessed ovarian function at both points, as well as mammary gland development at puberty and mammary tumor burden in middle age. Social isolation dissociated two components of puberty; it accelerated maturation of ovarian function while it simultaneously delayed mammary tissue development thereby increasing the exposure of developing breast parenchyma to high levels of estrogen. By mid‐life, socially isolated rats had greater tumor burden despite having entered estropause prematurely, demonstrating that isolation did not increase tumorigenesis by prolonging ovarian function. These findings are discussed in the context of facultative lifespan strategies for rats born at different times of year and those living in isolation or in a large burrow community. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 353–360, 2008.
Surrogate mobility and orientation affect the early neurobehavioral development of infant rhesus macaques (Macaca mulatta)
Authors: Dettmer Amanda M. , Ruggiero Angela M. , Novak Melinda A. , Meyer Jerrold S. , Suomi Stephen J.
Published: April 2008

A biological mother's movement appears necessary for optimal development in infant monkeys. However, nursery‐reared monkeys are typically provided with inanimate surrogate mothers that move very little. The purpose of this study was to evaluate the effects of a novel, highly mobile surrogate mother on motor development, exploration, and reactions to novelty. Six infant rhesus macaques (Macaca mulatta) were reared on mobile hanging surrogates (MS) and compared to six infants reared on standard stationary rocking surrogates (RS) and to 9–15 infants reared with their biological mothers (MR) for early developmental outcome. We predicted that MS infants would develop more similarly to MR infants than RS infants. In neonatal assessments conducted at Day 30, both MS and MR infants showed more highly developed motor activity than RS infants on measures of grasping (p = .009), coordination (p = .038), spontaneous crawl (p = .009), and balance (p = .003). At 2–3 months of age, both MS and MR infants displayed higher levels of exploration in the home cage than RS infants (p = .016). In a novel situation in which only MS and RS infants were tested, MS infants spent less time near their surrogates in the first five minutes of the test session than RS infants (p = .05), indicating a higher level of comfort. Collectively, these results suggest that when nursery‐rearing of infant monkeys is necessary, a mobile hanging surrogate may encourage more normative development of gross motor skills and exploratory behavior and may serve as a useful alternative to stationary or rocking surrogates. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 418–422, 2008.
No stable arm preference during the pre‐reaching period: A comparison of right and left hand kinematics with and without a toy present
Authors: Lynch A. , Lee H. M. , Bhat A. , Galloway J. C.
Published: April 2008

Adult hand preference emerges from complex developmental changes in arm and hand use during childhood. Recent reports have highlighted the importance of understanding arm and hand use during the first year of life including the period before reach onset. This longitudinal study tested the hypothesis that significant right–left differences exist in pre‐reaching arm movements. We examined right and left hand kinematics from 13 healthy infants during trials with and without a toy present from 8 weeks of age through the week of reach onset. Significant right–left differences were found, however there was no clear pattern within a condition or across conditions. Without a toy present, the right hand moved faster, yet ended further from midline, and displayed more movements during the Late phase compared to other phases. With a toy present, the right hand moved longer lengths, yet ended movements further away from the toy. When left and right hand kinematics were combined, previous findings of right hand kinematics alone were supported. Although infants begin adapting their pre‐reaching kinematics many weeks before reach onset, we did not find evidence of a systematic right–left difference before reach onset in movements with or without a toy present. Our results, coupled with other reports, suggest hand asymmetries begin to emerge over the year following reach onset amid developmental changes both within the infant, and the physical and social environment. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 390–398, 2008.
A prospective study of diurnal cortisol responses to the social experience of school transition in four‐year‐old children: Anticipation, exposure, and adaptation
Authors: Turner‐Cobb Julie M. , Rixon Lorna , Jessop David S.
Published: April 2008

This study examined psychosocial influences on hypothalamic‐pituitary‐adrenal axis activity in 105 4‐year‐old children transitioning to primary school. Measuring before, during, and after school transition over a period of up to12 months, salivary cortisol was assessed on awakening and early evening. Parents reported child temperament and teachers recorded adaptive behavior. Whilst cortisol at awakening and early evening increased from baseline to school transition, effects were not significant. A significant decrease occurred between transition and follow‐up and from baseline to follow‐up for both awakening and evening cortisol. Poorer effortful control was associated with high morning and steeper diurnal slope of cortisol at transition whilst surgency/extroversion was associated individually with greater morning and evening cortisol at transition and adaptation. Greater increase in internalizing social isolation during the first 6 months of school in more surgent/extrovert children predicted higher morning and evening cortisol at follow‐up. This study is the first to explore these adaptive relationships over a 12‐month period and supports social isolation over time as a key element in developmental endocrine activation. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 377–389, 2008.
Parasympathetic and sympathetic responses to the strange situation in infants and mothers from avoidant and securely attached dyads
Authors: Hill‐Soderlund Ashley L. , Mills‐Koonce W. Roger , Propper Cathi , Calkins Susan D. , Granger Douglas A. , Moore Ginger A. , Gariepy Jean‐Louis , Cox Martha J.
Published: April 2008

Vagal reactivity and salivary α‐amylase (sAA) were assessed in infants (M age = 13.55 months) and their mothers during the Strange Situation Paradigm (SSP) to investigate differences in physiological responses in a sample of insecure‐avoidant and securely‐attached dyads (N = 132). Infants classified as insecure‐avoidant had significantly higher vagal withdrawal during the SSP and higher sAA overall, suggesting that the avoidant attachment pattern is associated with a greater allostatic load. During separation episodes of the SSP, all mothers showed significant vagal withdrawal, suggesting greater attempts at regulation. During the last reunion, typically the most stressful episode for infants, mothers of secure infants showed greater vagal withdrawal than mothers of insecure‐avoidant infants, suggesting greater attempts by these mothers at interactive repair. Results for mothers and infants supported the allostatic load theory. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 361–376, 2008.
Social play in crested and japanese macaques: Testing the covariation hypothesis
Authors: Petit O. , Bertrand F. , Thierry B.
Published: April 2008

Most studies about social play have focused on its function in aiding socialization. It is not known whether play patterns vary by species according to specific adult social relationships. To test whether there is covariation between the form of play interactions and adult relationships, we studied social play in Japanese macaques (Macaca fuscata) and crested macaques (Macaca nigra). Comparative studies have shown that whereas low levels of tolerance and strict hierarchies characterize Japanese macaques, crested macaques display greater tolerance and relaxed dominance. The results showed that the former prefer less risky games, with minimal physical contact, ease of escape and a small number of play partners. The play bouts of the latter species involve closer contact and more partners. We conclude that play patterns covary with specific social style. Play patterns could have been selected for to introduce youngsters to their future social environment. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 399–407, 2008.
Morphallactic regeneration as revealed by region‐specific gene expression in the digestive tract of Enchytraeus japonensis (Oligochaeta, Annelida)
Authors: Takeo Makoto , Yoshida‐Noro Chikako , Tochinai Shin
Published: April 2008

Enchytraeus japonensis is a small oligochaete, which primarily reproduces asexually by fragmentation and regeneration. For precise analysis of the pattern formation during regeneration, we isolated three region‐specific genes (EjTuba, mino, and horu) expressed in the digestive tract. In growing worms, the expression of EjTuba in the head and mino in the trunk region just posterior to the head were observed in defined body segments, while the expression areas of EjTuba in the trunk and horu were proportional to the total number of body segments. In the regeneration process, expression of these genes disappeared once and recovered to their original pattern by day 7. In abnormal regeneration such as a bipolar head, mino was still expressed in the region next to both the normal and the ectopic heads. These results suggest that there is morphallactic as well as epimorphic or inductive regulation of the body patterning during regeneration of E. japonensis. Developmental Dynamics 237:1284‐1294, 2008. © 2008 Wiley‐Liss, Inc.
Retinoic acid induces prostatic bud formation
Authors: Vezina Chad M. , Allgeier Sarah H. , Fritz Wayne A. , Moore Robert W. , Strerath Michael , Bushman Wade , Peterson Richard E.
Published: April 2008

Formation of prostatic buds from the urogenital sinus (UGS) to initiate prostate development requires localized action of several morphogenetic factors. This report reveals all‐trans‐retinoic acid (RA) to be a powerful inducer of mouse prostatic budding that is associated with reciprocal changes in expression of two regulators of budding: sonic hedgehog (Shh) and bone morphogenetic protein 4 (Bmp4). Localization of retinoid signaling and expression of RA synthesis, metabolism, and receptor genes in the UGS on embryonic days 14.5–17.5 implicate RA in the mechanism of bud initiation. In UGS organ culture, RA increased prostatic budding, increased Shh expression, and decreased Bmp4. Prostatic budding was stimulated in the absence of RA by recombinant SHH, by blocking BMP4 signaling with NOGGIN, or by combined treatment with SHH and NOGGIN in UGS organ culture media. These observations suggest that reciprocal changes in hedgehog and BMP signaling by RA may regulate bud initiation. Developmental Dynamics 237:1321‐1333, 2008. © 2008 Wiley‐Liss, Inc.
Mice with an anterior cleft of the palate survive neonatal lethality
Authors: Gu Shuping , Wei Na , Yu Xueyan , Jiang Yiping , Fei Jian , Chen YiPing
Published: April 2008

Many genes are known to function in a region‐specific manner in the developing secondary palate. We have previously shown that Shox2‐deficient embryos die at mid‐gestation stage and develop an anterior clefting phenotype. Here, we show that mice carrying a conditional inactivation of Shox2 in the palatal mesenchyme survive the embryonic and neonatal lethality, but develop a wasting syndrome. Phenotypic analyses indicate a delayed closure of the secondary palate at the anterior end, leading to a failed fusion of the primary and secondary palates. Consistent with a role proposed for Shox2 in skeletogenesis, Shox2 inactivation causes a significantly reduced bone formation in the hard palate, probably due to a down‐regulation of Runx2 and Osterix. We conclude that the secondary palatal shelves are capable of fusion with each other, but fail to fuse with the primary palate in a developmentally delayed manner. Mice carrying an anterior cleft can survive neonatal lethality. Developmental Dynamics 237:1509‐1516, 2008. © 2008 Wiley‐Liss, Inc.
Synthesis, X‐ray Structure and Reactivity of a Sterically Protected Azobisphenol Ligand: On the Quest for New Multifunctional Active Ligands
Authors: Evangelio Emi , Saiz‐Poseu Javier , Maspoch Daniel , Wurst Klaus , Busque Felix , Ruiz‐Molina Daniel
Published: April 2008

Different synthetic routes have been explored for the synthesis of the sterically protected 2,2′‐dihydroxy‐4,3,4,3′‐tetra‐tert‐butylazobenzene ligand (2), which is an excellent candidate for the development of valence tautomeric complexes. As expected, such a ligand exhibits good reactivity with transition‐metal ions, as shown by the synthesis and characterization of the new cobalt complex [Co(22–)(H2O)3]Cl·2.5EtOH·H2O (8). This fact together with the reversible deprotonation/protonation of the phenol groups has been used to create a chromophoric array of three states with significantly different colours, which can interconvert reversibly between them. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Synthesis and Reactivity of Oxametallacyclic Niobium Compounds by Using α,β‐Unsaturated Carbonyl Ligands
Authors: Arteaga‐Müller Rocío A. , Sánchez‐Nieves Javier , Royo Pascual , Mosquera Marta E. G.
Published: April 2008

Reduction of mono(cyclopentadienyl)niobium complexes [NbCpRCl4] [CpR = C5Me4H (1), C5H4SiMe2Cl (2), C5H4SiMe3 (3)] with Na/Hg in the presence of methyl methacrylate [MMA, CH2=C(Me)C(O)OMe (a)], methyl acrylate [MA, CH2=CHC(O)OMe (b)] and mesityl oxide [MO, CMe2=CHC(O)Me (c)] afforded the corresponding derivatives [NbCpRCl2(LL)] [CpR = C5Me4H, LL = MMA (1a); CpR = C5H4SiMe2Cl, LL = MMA (2a), MA (2b), MO (2c); CpR = C5H4SiMe3, LL = MMA (3a), MA (3b)] in variable yields depending on both the cyclopentadienyl and the α,β‐unsaturated carbonyl compounds. The reactivity of these complexes was studied toward protic and Lewis acids. Addition of triflic acid TfOH (Tf = CF3SO2) to 3b gave the triflate complex [NbCpRCl2{(CH2)2C(O)OMe}(OTf)] [CpR = C5H4SiMe3 (4)]. The Lewis acids E(C6F5)3 (E = B, Al) reacted with complexes 2b and 3b to give the three‐membered metallacyclic (or η2‐enone) compounds [NbCpRCl2{η2‐CH2=CHC(OMe){O·E(C6F5)3}}] [CpR = C5H4SiMe2Cl, E = B (5), Al (6); CpR = C5H4SiMe3, E = B (7), Al (8)], which decomposed to the corresponding adducts MA·E(C6F5)3. The same reaction with the 2a and 3a derivatives only allowed the observation of the corresponding adducts MMA·E(C6F5)3. Complexes 2a,b and 3a,b reacted with CO with elimination of the acrylate compounds, MA and MMA, respectively, to give the carbonylniobium(III) compounds [NbCpRCl2(CO)2]2 [CpR = C5H4SiMe2Cl (9), C5H4SiMe3 (10)]. Analogous reactions with CNAr showed the elimination of the free MA and MMA compounds. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
A Convergent Approach for the Generation of Dendrimers Containing the ­[Ru3O(CH3COO)6] Electroactive Core
Authors: Nikolaou Sofia , Toma Henrique E.
Published: April 2008

We report on a convergent approach for the generation of dendrimers containing the [Ru3O(ac)6] electroactive core, of great interest as multielectron transfer catalysts. The proposed strategy is based on the generation of the trimeric complex [{Ru3O(ac)6(4‐pic)2(pz)}2‐μ2‐Ru3O(ac)6(CH3OH)]3+ (ac = acetate, 4‐pic = 4‐methylpyridine, pz = pyrazine). In this complex, the labile CH3OH ligand can be displaced by the bridging pyrazine ligand of [Ru3O(ac)6(pz)3]0, leading to the self‐assembly of the [{[Ru3O(ac)6(4‐pic)2(pz)]2‐μ2‐Ru3O(ac)6(pz)}3‐μ3‐Ru3O(ac)6]n+ dendrimer containing 30 ruthenium atoms.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Silylene and Germylene Intermediates in the Reactions of Silole and Germole Dianions with N,N′‐Di‐tert‐butylethylenediimine
Authors: Toulokhonova Irina S. , Timokhin Vitaly I. , Bunck David N. , Guzei Ilia , West Robert , Müller Thomas
Published: April 2008

Spiro‐diazasilole (germole) adducts were observed in reactions of dilithium salts of silole and germole dianions with N,N′‐di‐tert‐butylethylenediimine in THF at room temperature. A proposed mechanism of the reaction includes metallation of N,N′‐di‐tert‐butylethylenediimine and the formation of an intermediate silylene or germylene. This reaction mechanism was supported by experimental data and theoretical calculations. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Thermodynamic Study of σH Complexes in Nucleophilic Aromatic Substitution Reactions: Relative Stabilities of Electrochemically Generated Radicals
Authors: Gallardo Iluminada , Guirado Gonzalo
Published: April 2008

The mechanism for the electrochemical oxidation of σH complexes, such as 1‐hydro‐1‐alkoxy/sulfoxy or ‐fluoro‐2,4‐dinitro/2,4,6‐trinitrocyclohexadienyl anions, has been widely studied by means of cyclic voltammetry and controlled‐potential electrolysis. Previous studies have shown that the electrochemical oxidation of σH complexes, formed by the addition of carbon or nitrogen nucleophiles followed by a two electron mechanism, corresponding to the formal elimination of the hydride anion (nucleophilic aromatic substitution of hydrogen mechanism, the NASH mechanism). For these σH complexes (Nu– = OH–, –OR, –SR, –F), the electrochemical reaction takes place by a one‐electron mechanism and is followed by the radical elimination of the leaving group with the consequent recovery of the starting material. This mechanism is similar to that proposed for the electrochemical oxidation of σX complexes (nucleophilic aromatic substitution of a heteroatom, the NASX mechanism). The operating mechanism in each case, the NASH or NASX, can be rationalized in terms of thermodynamics. The standard potentials of the σ complex and/or the leaving group as well as the bond dissociation energies (BDEs) are determinant factors. This study has not led to a significant improvement in the electrochemical preparation of aromatic‐substituted compounds, but does help to understand and predict the usefulness or uselessness of using the nucleophilic aromatic substitution route to obtain a desired product. Finally, the current approach extends the electrochemical methodology to different chemical fields, for example, to general nondestructive methods for the detection, identification, and quantification of either organic pollutants or explosives in different solvents. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Applications of Chiral Ionic Liquids
Authors: Bica Katharina , Gaertner Peter
Published: April 2008

Despite the rapid growth in chiral ionic liquid (CIL) research, successful applications remained hidden for some time, but are increasing fast nowadays. The major part of this review deals with the use of CILs as solvents, catalysts or ligands in asymmetric synthesis. Chiral recognition abilities in spectroscopic techniques such as NMR, NIR or fluorescence spectroscopy are discussed as well as the application of CILs for separation in chromatography. In this review, we focus entirely on the applications of CILs; publications dealing with design and synthesis of CILs only are not mentioned. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Photosensitized Electron Transfer Oxidation of Sulfides: A Steady‐State Study
Authors: Bonesi Sergio M. , Fagnoni Maurizio , Albini Angelo
Published: April 2008

The photosensitized electron‐transfer oxidation of a series of ethyl sulfides RSEt (1, R = C12H25; 2, PhCH2CH2; 3, PhCH2; 4, PhCMe2; 5, Ph2CH) has been examined in acetonitrile and the product distribution discussed on the basis of the mechanisms proposed. In nitrogen‐flushed solutions, cleaved alcohols and alkenes are formed, whereas under oxygen, in reactions that are 10–70 times faster, sulfoxides and cleaved aldehydes and ketones are formed in addition to the aforementioned products. Two sensitizers are compared, 9,10‐dicyanoanthracene (DCA) and 2,4,6‐triphenylpyrylium tetrafluoroborate (TPP+BF4–), the former giving a higher proportion of the sulfoxide, the latter of cleaved carbonyls. The sulfoxidation is due to the contribution of the singlet oxygen path with DCA. Oxidative cleavage, on the other hand, occurs both with DCA and with TPP+ which is known to produce neither singlet oxygen nor the superoxide anion. This process involves deprotonation from the α position of the sulfide radical cation, but the TPP+ results suggest that O2·– is not necessarily involved and non‐activated oxygen forms a weak adduct with the radical cation promoting α‐hydrogen transfer, particularly with benzylic derivatives.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Highly Stereoselective Metal‐Mediated Entry to Functionalized Tetrahydrothiophenes by Barbier‐Type Carbonyl‐Addition Reactions
Authors: Alcaide Benito , Almendros Pedro , Martínez del Campo Teresa
Published: April 2008

Reactions of tetrahydrothiophene‐3‐carbaldehydes with stabilized organometallic reagents were investigated in aqueous media. Tetrahydrothiophene‐3‐carbaldehydes and a variety of stabilized organic halides undergo stereocontrolled coupling under Barbier‐type conditions in the presence of different metals (zinc, tin, indium) and additives [ammonium chloride, hydrobromic acid, hafnium(IV) chloride, bismuth(III) chloride]. The regiochemistry of the carbonyl addition processes, when applicable, was excellent.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Parametric study of ductile moment‐resisting steel frames: A first step towards Eurocode 8 calibration
Authors: Sanchez‐Ricart L. , Plumier A.
Published: April 2008

A parametric study of 13 608 ductile moment‐resisting steel frames designed according to Eurocodes 3 and 8 is performed. A flowchart for the evaluation of the seismic‐resistant capacity of the designed frames is developed based on the N2 method. The design structural overstrength, ductility supply, plastic redistribution parameter, supply reduction factor and performance ratio of the frames are analysed. We determine that the frames have performance ratios higher than 1, mostly due to high values of design structural overstrength, showing that the seismic supply produced by the restraints of Eurocodes 3 and 8 is always higher than the seismic demand. Copyright © 2008 John Wiley & Sons, Ltd.
Human cytomegalovirus load measurement and its applications for pre‐emptive therapy in patients undergoing hematopoietic stem cell transplantation
Authors: Baldanti Fausto , Lilleri Daniele , Gerna Giuseppe
Published: April 2008

The hematopoietic stem cell transplantation (HSCT) setting is a rapidly evolving field, and procedures with a high degree of complexity are now entering into the clinic. The risk of developing opportunistic viral infections increases with the level of human leukocyte antigen disparity between the donor and the recipient of allogeneic HSCT and is enhanced by graft manipulations such as T‐cell depletion or immune suppression required to control graft versus host disease (GVHD) or rejection. Among the opportunistic viral infections potentially hampering the outcome of HSCT, human cytomegalovirus (HCMV) infection plays a major role. In the early 1980s, before the introduction of effective antiviral treatment, HCMV disease accounted for the high mortality in recipients of allogeneic HSCT. In more recent years, the availability of HCMV‐specific antiviral agents (ganciclovir, GCV, foscarnet, PFA and cidofovir, CDV) led to a dramatic decrease in HCMV‐related morbidity and mortality. However, HCMV infection still remains a major concern in the HSCT setting. Historically, treatment of HCMV infection in HSCT recipients (HSCTR) evolved from treatment of overt HCMV disease to universal prophylaxis or pre‐emptive treatment of active infection, in parallel with the improvement of techniques for diagnosing and monitoring HCMV infection in transplant recipients. Copyright © 2008 John Wiley & Sons, Ltd.
Effect of bearing size on the long‐term wear, wear debris, and ion levels of large diameter metal‐on‐metal hip replacements—An in vitro study
Authors: Leslie Ian , Williams Sophie , Brown Chris , Isaac Graham , Jin Zhongmin , Ingham Eileen , Fisher John
Published: April 2008

Hip resurfacing arthroplasty has become a popular alternative to conventional hip surgery. Surface replacements with bearing sizes of 55 mm (n = 5) and 39 mm (n = 5) were tested in a hip simulator for 15 million cycles (Mc). Wear debris was isolated from the serum lubricant and characterized by field emmitting gun scanning electorn microscopy, and ion levels were measured via inductively coupled plasma mass spectroscopy at intervals throughout the test. The 39 mm bearings showed significantly greater bedding in volumetric wear (2.58 mm3) compared with the 55 mm bearings (1.15 mm3). There was no significant difference between the steady state wear rates (1–15 Mc) between the two sizes (0.10 and 0.09 mm3/Mc, respectively); however, this parity only became clear after 7 Mc. The wear debris isolated was oval in morphology with a mean particle size of 28 nm and a range of 9–108 nm. The Co levels measured at 0.13 Mc were significantly greater than at 3.6 Mc for both bearing sizes (10926 ppb and 176 ppb, respectively). After 0.5 Mc, the Co levels from the 39 mm bearings were significantly higher than the 55 mm (11,007 vs. 1475 ppb). The wear results support previous findings showing that increasing the femoral head size decreased volumetric bedding in wear. The ion levels measured suggest both bearing sizes have similar initial wear rates; however, the 55 mm bearings reach steady state wear more rapidly. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Alternative splicing of Nav1.5: An electrophysiological comparison of ‘neonatal’ and ‘adult’ isoforms and critical involvement of a lysine residue
Authors: Onkal Rustem , Mattis Joanna H. , Fraser Scott P. , Diss James K.J. , Shao Dongmin , Okuse Kenji , Djamgoz Mustafa B.A.
Published: April 2008

In developmentally regulated D1:S3 splicing of Nav1.5, there are 31 nucleotide differences between the 5′‐exon (‘neonatal’) and the 3′‐exon (‘adult’) forms, resulting in 7 amino acid differences in D1:S3‐S3/S4 linker. In particular, splicing replaces a conserved negative aspartate residue in the ‘adult’ with a positive lysine. Here, ‘neonatal’ and ‘adult’ Nav1.5 α‐subunit splice variants were stably transfected into EBNA‐293 cells and their electrophysiological properties investigated by whole‐cell patch‐clamp recording. Compared with the ‘adult’ isoform, the ‘neonatal’ channel exhibited (1) a depolarized threshold of activation and voltage at which the current peaked; (2) much slower kinetics of activation and inactivation; (3) 50% greater transient charge (Na+) influx; (4) a stronger voltage dependence of time to peak; and (5) a slower recovery from inactivation. Tetrodotoxin sensitivity and VGSCβ1‐4 mRNA expression levels did not change. The significance of the charge‐reversing aspartate to lysine substitution was investigated by mutating the lysine in the ‘neonatal’ channel back to aspartate. In this ‘neonatal K211D’ mutant, the electrophysiological parameters studied strongly shifted back towards the ‘adult’, that is the lysine residue was primarily responsible for the electrophysiological effects of Nav1.5 D1:S3 splicing. Taken together, these data suggest that the charge reversal in ‘neonatal’ Nav1.5 would (1) modify the channel kinetics and (2) prolong the resultant current, allowing greater intracellular Na+ influx. Developmental and pathophysiological consequences of such differences are discussed. J. Cell. Physiol. 216: 716–726, 2008, © 2008 Wiley‐Liss, Inc.
Altered expression of endoplasmic reticulum aminopeptidases ERAP1 and ERAP2 in transformed non‐lymphoid human tissues
Authors: Fruci Doriana , Giacomini Patrizio , Nicotra Maria R. , Forloni Matteo , Fraioli Rocco , Saveanu Loredana , van Endert Peter , Natali Pier Giorgio
Published: April 2008

The endoplasmic reticulum (ER) aminopeptidases ERAP1 and ERAP2 contribute to generate HLA class I binding peptides. Recently, we have shown that the expression of these enzymes is high and coordinated (with each other and with HLA class I molecules) in immortalized B cells, but variable and imbalanced in human tumour cell lines of various non‐lymphoid lineages. Herein, this issue was investigated in vivo by testing ERAP1 and ERAP2 expression in normal non‐lymphoid tissues and their malignant counterparts. ERAP1 and ERAP2 were detected exclusively in the epithelial cells of over half of the tested normal tissues. Four ERAP1/ERAP2 phenotypes (+/+, −/−, +/− and −/+) were detected, and the presence of either or both enzymes was not necessarily associated with HLA class I expression. In more than 160 neoplastic lesions, the expression of either or both aminopeptidases was retained, lost (most frequently, particularly ERAP1) or acquired as compared to the normal counterparts, depending on the tumour histotype. The double‐negative (−/−) phenotype was the most frequent, and significantly (P = 0.013) associated with a lack of detectable HLA class I antigens. In selected neoplastic lesions, ERAP1 and ERAP2 were also tested for their enzymatic (peptide‐trimming) activities. Expression and function were found to correlate, indicating that immunohistochemistry detects active enzymes in vivo. Thus, dissociation in the expression of ERAP1, ERAP2 and HLA class I may already be present in some normal tissues, but malignant transformation causes additional losses, gains and imbalances in specific tumour histotypes, and these alter the peptide‐trimming ability of tumour cells in vivo. J. Cell. Physiol. 216: 742–749, 2008, © 2008 Wiley‐Liss, Inc.
Structure and function of 2:1 DNA polymerase·DNA complexes
Authors: Tang Kuo‐Hsiang , Tsai Ming‐Daw
Published: April 2008

DNA polymerases are required for DNA replication and DNA repair in all of the living organisms. Different DNA polymerases are responsible different stages of DNA metabolism, and many of them are multifunctional enzymes. It was generally assumed that the different reactions are catalyzed by the same enzyme molecule. In addition to 1:1 DNA polymerase·DNA complex reported by crystallization studies, 2:1 and higher order DNA polymerase·DNA complexes have been identified in solution studies by various biochemical and biophysical approaches. Further, abundant evidences for the DNA polymerase–DNA interactions in several DNA polymerases suggested that the 2:1 complex represents the more active form. This review describes the current status of this emerging subject and explores their potential in vitro and in vivo functional significance, particularly for the 2:1 complexes of mammalian DNA polymerase β (Pol β), the Klenow fragment of E. coli DNA polymerase I (KF), and T4 DNA polymerase. J. Cell. Physiol. 216: 315–320, 2008. © 2008 Wiley‐Liss, Inc.
Membrane‐assisted vapor stripping: energy efficient hybrid distillation–vapor permeation process for alcohol–water separation
Authors: Vane Leland M , Alvarez Franklin R
Published: April 2008

BACKGROUND: Energy efficient alternatives to distillation for alcohol recovery from dilute solution are needed to improve biofuel sustainability. A process integrating steam stripping with a vapor compression step and a vapor permeation membrane separation step is proposed. The objective of this work is to estimate the energy and process costs required to make a fuel grade ethanol (0.5 wt% water) from 1 and 5 wt% ethanol aqueous streams using the proposed process.

RESULTS: Using process simulation and spreadsheeting software, the proposed membrane‐assisted vapor stripping process was estimated to require as little as 8.9 MJ of fuel‐equivalent energy per kg of fuel grade ethanol recovered from a 1 wt% ethanol feed stream, 2.5 MJ kg−1 for a 5 wt% ethanol solution. This represents an energy saving of at least 43% relative to standard distillation producing azeotropic ethanol (6 wt% water). Process costs were also found to be lower than for distillation at the 3.0 × 106 kg‐ethanol year−1 scale modeled.

CONCLUSION: In this hybrid system, the stripping column provides high ethanol recoveries and low effluent concentrations while the vapor compression‐membrane component enables the efficient recovery of latent and sensible heat from both the retentate and permeate streams from the membrane system. Published in 2008 by John Wiley & Sons, Ltd.
Purification and characterization of an organic solvent and detergent‐tolerant novel protease produced by Bacillus sp. RKY3
Authors: Reddy LVA , Wee Young‐Jung , Ryu Hwa‐Won
Published: April 2008

BACKGROUND: Purification and characterization of a novel protease produced by Bacillus sp. RKY3, has been investigated, with special emphasis on the stability of the enzyme in the presence of different oxidizing and reducing agents as well as organic solvents. The enzyme was purified in two steps through concentration of the crude enzyme by ammonium sulfate precipitation, followed by anion exchange chromatography.

RESULTS: The purified protease had a molecular mass of approximately 38 kDa, which was highly active over a broad range of pH between 7.0 and 9.0 and was also stable over a wide pH range from 5.0 to 11.0. Although the optimum temperature for enzyme activity was found to be 60 °C, it was rapidly deactivated at temperatures above 60 °C. It also showed good stability at 50 °C, with a 70 min half‐life. Ca2+ ions did not greatly enhance the activity or the stability of the enzyme. PMSF (1 mmol L−1) completely inhibited the protease activity, and thus the purified protease was considered to be serine protease. The purified protease was stable with oxidants (H2O2, 2%), reducing agents (sodium dodecyl sulfate, 2%), and organic solvents (25%) such as benzene, hexane, and toluene.

CONCLUSION: The purified enzyme, protease, seems to possess potential applications in protease‐based detergent and bleaching industries. The enzymatic activity against a wide variety of substrates suggests that the purified enzyme should be investigated for a range of commercial applications, especially for soy protein and gelatin hydrolysis in the food processing industry. Copyright © 2008 Society of Chemical Industry
Transneuronal retrograde viral labeling in the brain stem and hypothalamus is more intense from the left than from the right adrenal gland
Authors: Tóth Ida E. , Wiesel Ory , Tóth Dorina E. , Boldogkői Zsolt , Halász Béla , Gerendai Ida
Published: April 2008

Previous studies using the viral transneuronal tracing technique demonstrated central autonomic circuits involved in the innervation of the adrenal gland. Since increasing number of data indicate laterality in the neuroendocrine system, we aimed to investigate whether the supraspinal innervation of the adrenal gland exhibits asymmetry or not. The central circuitry involved in the innervation of the left and the right adrenal gland was studied in individual rats by dual transneuronal tracing using isogenic recombinant strains (Ba‐DupGreen and Ba‐Duplac expressing lacZ) of Bartha strain of pseudorabies virus. Viral infection of brain nuclei (dorsal vagal nucleus, nucleus of the solitary tract, caudal raphe nuclei, A5 cell group, hypothalamic paraventricular nucleus) from the left adrenal was more severe than that from the right organ. Dual‐infected neurons were present both in the brain stem and in the hypothalamus. The results indicate a predominance in the supraspinal innervation of the left adrenal gland, and that each adrenal gland is innervated both by side‐specific neurons and by neurons that project to both organs. Microsc. Res. Tech., 2008. © 2008 Wiley‐Liss, Inc.