bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigating the permanent electric dipole moment of β‐lactoglobulin fibrils, using transient electric birefringence
Authors: Rogers S. S. , Venema P. , van der Ploeg J. P. M. , van der Linden E. , Sagis L. M. C. , Donald A. M.
Published: February 2006

Amyloid fibrils, which are polymeric assemblies of protein molecules, have been intensively studied on a structural level, yet due to complications such as the disorder within the molecules, several aspects of their structure remain mysterious. Similarly, the kinetics of assembly are not well understood. Here we investigate the electric dipole moment of β‐lactoglobulin fibrils, a model amyloid fibril system, by applying the technique of transient electric birefringence. This moment appears to be large, and comparable to the total moment of the constituent protein monomers if they were joined in a chain, head‐to‐tail, without changing conformation, suggesting an ordered joining of monomers in the fibril. Such an ordered assembly may have implications for the assembly mechanism of β‐lactoglobulin fibrils in particular, and amyloid fibrils in general. © 2006 Wiley Periodicals, Inc. Biopolymers 82: 241–252, 2006

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Sorption of Chromium(VI) from Aqueous Solution by Cassava (Manihot sculenta Cranz.) Waste Biomass
Authors: Horsfall Michael , Ogban Fred , Akporhonor Eyitemi Emmanuel
Published: February 2006

The sorption of highly toxic CrVI ions by cassava waste biomass was quantitatively investigated. The sorption was found to be influenced by several physico‐chemical factors such as agitation speed, temperature, contact time, pH, and sorbent/sorbate ratio. The adsorption data at equilibrium were fitted to Freundlich and Langmuir isotherms. The monolayer sorption capacity was found to be 61.79 mg of CrVI per gram of biomass. The kinetics of CrVI adsorption to pure cassava‐tuber‐bark wastes were determined based on a pseudo‐second‐order‐rate model using the batch‐sorption technique at a temperature of 30°. The kinetics data suggest that the adsorption process is exothermic, and that the rate‐limiting step is physisorption. Negative ΔGads values indicate that the adsorption is spontaneous and exothermic in nature. Also, under optimal conditions (in agitated 1M H2SO4 at 30°), the cassava waste biomass appears to be recyclable.
New Antioxidant Phenolic Glycosides from Walsura yunnanensis
Authors: Luo Xiao‐Dong , Wu Da‐Gang , Cai Xiang‐Hai , Kennelly Edward J.
Published: February 2006

Four new polyphenolic glycosides (1–4) were isolated from the BuOH extract of the bark of Walsura yunnanenis C. Y. Wu. These compounds comprise two lignans, i.e., the 9‐O‐α‐L‐arabinopyranosides 1 and 2 of (−)‐isolariciresinol and of (+)‐5‐methoxyisolariciresinol, respectively, and the two phenolic glycosides 3,4,5‐trimethoxyphenyl 2‐O‐(α‐L‐fucopyranosyl)‐β‐D‐glucopyranoside (3) and 3,5‐dihydroxyphenyl 6‐O‐(4‐hydroxy‐3,5‐dimethoxybenzoyl)‐β‐D‐glucopyranoside (walsuraside; 4). In addition, three known compounds, 3,4,5‐trimethoxyphenyl β‐D‐glucopyranoside, asperglaucide, and butyl α‐D‐fructofuranoside were identified. Their structures were elucidated spectroscopically and by chemical transformation (hydrolysis). The new compounds 1, 2, and 4 displayed significant antioxidant activities, with IC50 values in the range of ca. 42 to 49 μg/ml.
Preoperative palliation of newborn obstructed total anomalous pulmonary venous connection by endovascular stent placement
Authors: Kyser James P. , Bengur A. Resai , Siwik Ernest S.
Published: February 2006

Patients with obstructed total anomalous pulmonary venous connection (TAPVC) usually present critically ill and continue to be extremely challenging with presurgical stabilization. We present an extra corporeal membrane oxygenation (ECMO)‐dependent neonate with obstructed TAPVC that was successfully palliated with transvenous stent placement in the obstructed vertical vein. © 2006 Wiley‐Liss, Inc.
Percutaneous closure of postoperative ventricular septal defects with the amplatzer device
Authors: Walsh Mark A. , Coleman David M. , Oslizlok Paul , Walsh Kevin P.
Published: February 2006

The objective of this study was to look at the procedure, the results, and the follow‐up of patients who underwent percutaneous closure of a residual ventricular septal defect (VSD) following a surgical closure using the Amplatzer VSD device. Four patients had an original diagnosis of tetralogy of Fallot, two patients had a patch leak following a surgical repair of a VSD, and three patients had a VSD not repaired at the time of surgery. All patients fulfilled the currently accepted surgical criterion for reoperation (Qp/Qs > 1.5). The mean Qp/Qs was 1.8 ± 0.3 (1.5–2.3). Four patients underwent VSD closure using an Amplatzer perimembranous VSD device and in five patients an Amplatzer muscular VSD device was implanted. We performed percutaneous closure in nine patients. The size of the residual shunt ranged from 6 to 14 mm and the size of device used ranged from 8 to 16 mm. The arteriovenous loop needed to be recreated in two patients because of failure to advance the delivery sheath. There was complete closure of the defect in six cases, and a small residual shunt remained in three cases. Percutaneous closure of postoperative VSDs appears to be an effective way to resolve a hemodynamically significant residual shunt. There were no difficulties encountered with implantation of the devices. These promising short‐term results need reinforcement with additional long‐term data. © 2006 Wiley‐Liss, Inc.
Stenting coronary trifurcation lesions: Is “ménage à trois” the solution?
Authors: El‐Jack Seifeddin S. , Pornratanarangsi Suwatchai , Ormiston John A. , Webster Mark W.I.
Published: February 2006

Percutaneous treatment of coronary stenoses involving important side branches remains a challenge to the interventionist. We describe two cases of stent deployment in coronary trifurcation lesions. Triple kissing balloon inflation appears important for achieving an optimal angiographic and clinical result. © 2006 Wiley‐Liss, Inc.
Should we perform preoperative coronary angiography in all cases of atrial myxomas?
Authors: Janas Robert , Jutley Rajwinder S. , Fenton Paul , Sarkar Pradeep
Published: February 2006

The prevalence of coronary disease is high in patients with atrial myxomas yet routine angiography is not performed. Moreover, some tumors have angiographically detectable neovascularity, which can alter surgical planning. We report two cases that support our recommendation for performing coronary angiography in all cases diagnosed with cardiac myxomas. © 2006 Wiley‐Liss, Inc.
A Versatile and Efficient Ligand for Copper‐Catalyzed Formation of CN, CO, and PC Bonds: Pyrrolidine‐2‐Phosphonic Acid Phenyl Monoester
Authors: Rao Honghua , Jin Ying , Fu Hua , Jiang Yuyang , Zhao Yufen
Published: February 2006

A new and readily available bidentate ligand, namely, pyrrolidine‐2‐phosphonic acid phenyl monoester (PPAPM), has been developed for the copper‐catalyzed formation of CN, CO, and PC bonds, and various N‐, O‐, and P‐arylation products were synthesized in good to excellent yields by using the CuI/PPAPM catalyst system. Addition of the PPAPM ligand greatly increases the reactivity of the copper catalyst, and the resulting versatile and efficient catalyst system is of widespread and practical application in cross‐coupling reactions.
Significance of thymidylate synthase gene expression level in patients with adenocarcinoma of the lung
Authors: Hashimoto Hiroshi , Ozeki Yuichi , Sato Mitsuharu , Obara Kiyohaya , Matsutani Noriyuki , Nakagishi Yoshinori , Ogata Toshiro , Maehara Tadaaki
Published: February 2006

BACKGROUND

Thymidylate synthase (TS) catalyzes the methylation of deoxyuridine monophosphate (dUMP) to deoxythymidine monophosphate (dTMP) and is a key enzyme for DNA synthesis. High expression of TS is thought to be associated with poor prognosis in some kinds of cancers. However, this association has not been clarified for nonsmall cell lung carcinoma. In the current study, the authors investigated the clinicopathologic significance of TS mRNA levels and the correlation with cellular proliferation in patients with lung adenocarcinoma.

METHODS

The expression levels of TS mRNA were measured in 47 lung adenocarcinoma tissues using the Taq‐Man real‐time reverse transcriptase‐polymerase chain reaction (RT‐PCR) method and examined the clinicopathologic significance of TS expression. To clarify the correlation between TS expression level and cell proliferation, the Ki‐67 labeling index was also examined using immunohistochemical staining.

RESULTS

A positive correlation was observed between the expression levels of TS mRNA and stage of disease, lymph node metastasis, or tumor differentiation (P = .015). The higher expression group of TS mRNA showed a significantly poorer prognosis than the group with lower expression (P = .042). Moreover, there was a strong correlation noted between the expression levels of TS mRNA and the Ki‐67 labeling index (P = .009).

CONCLUSIONS

The results of the current study demonstrated that TS may be associated with stage of disease, lymph node metastasis, tumor differentiation, prognosis, and tumor cell proliferation. These results suggest that the expression levels of TS mRNA may be useful for predicting the malignant potential in patients with lung adenocarcinoma. Cancer 2006. © 2006 American Cancer Society.
Immunoreactivity for cocaine‐ and amphetamine‐regulated transcript in rat sympathetic preganglionic neurons projecting to sympathetic ganglia and the adrenal medulla
Authors: Fenwick Natalie M. , Martin Carolyn L. , Llewellyn‐Smith Ida J.
Published: February 2006

Many sympathetic preganglionic neurons (SPN) in the intermediolateral cell column (IML) contain cocaine‐ and amphetamine‐regulated transcript (CART), but the function of these CART‐immunoreactive (IR) neurons is unknown. To test the possibility that CART might mark SPN involved in cardiovascular regulation, we first established whether all CART neurons in the spinal cord were SPN by double‐immunofluorescent labelling for CART and choline acetyltransferase (ChAT). All autonomic subnuclei contained SPN immunoreactive for ChAT plus CART. Occasional ChAT‐negative, CART‐positive neurons occurred adjacent to the IML, indicating the existence of CART‐IR interneurons. We then retrogradely labelled SPN with cholera toxin subunit B (CTB) from a variety of targets and used double immunofluorescence to detect CTB and CART. Among SPN in the IML, 43% projecting to the coeliac ganglion, 34% projecting to the major pelvic ganglion, and about 15% projecting to the superior cervical ganglion or adrenal medulla contained CART. CART also occurred in most SPN projecting to the major pelvic ganglion from either the central autonomic area (63%) or the intercalated nucleus (58%). Finally, we used drug‐induced hypotension in conscious rats to evoke Fos immunoreactivity in barosensitive SPN and immunostained to reveal Fos and CART. CART immunoreactivity was present in 41% of the Fos‐IR barosensitive neurons, which were concentrated in the IML of segments T5–T13. CART‐positive, Fos‐negative neurons also occurred in the same segments. These results indicate that CART occurs in barosensitive SPN, nonbarosensitive SPN, and interneurons. Thus, CART is not an exclusive marker for cardiovascular SPN but is likely to influence many autonomic activities. J. Comp. Neurol. 495:422–433, 2006. © 2006 Wiley‐Liss, Inc.
Organization of somatosensory cortical areas in the naked mole‐rat (Heterocephalus glaber)
Authors: Henry Erin C. , Remple Michael S. , O'Riain M. Justin , Catania Kenneth C.
Published: February 2006

Multiunit electrophysiology was combined with histological analysis of cortical sections to investigate the organization of somatosensory areas in the naked mole‐rat. We provide new details for the organization of primary somatosensory cortex (S1) and identify cortical modules and barrels that correspond to the representations of different body parts. In addition, details of the location and organization of secondary somatosensory cortex (S2) are reported, and evidence for a third somatosensory representation, likely the parietal ventral area (PV), is provided and discussed. S1 contained a complete and systematic representation of the contralateral body surface and oral structures. The orientation of S1 was inverted, with the lower body represented medially and the face and oral structures located rostrolaterally. The S2 representation was found in caudolateral cortex forming a mirror image of S1. The two areas were joined at the representation of the vibrissae and snout, so that the orientation of S2 formed an upright representation of the body in cortex. Receptive fields for S2 were consistently larger than those in S1. Evidence for the presumptive parietal ventral area, lateral to S2, suggests that this area may be an inverted mirror image of S2. By aligning the electrophysiological maps of body representations with cytochrome oxidase‐reacted cortical sections we were able to identify modules related to the buccal pad, chin, vibrissae, forelimb, hindlimb, trunk, tongue, lower incisor, and upper incisors. The orofacial modules in lateral cortex resemble similar modules reported to relate to oral structures previously described in the laboratory rat, owl monkey, and squirrel monkey. J. Comp. Neurol. 495:434–452, 2006. © 2006 Wiley‐Liss, Inc.
Meshfree collocation solution of boundary value problems via interpolating moving least squares
Authors: Netuzhylov Hennadiy
Published: February 2006

This paper presents a meshfree interpolating moving least squares (IMLS) method based on singular weights for the solution of partial differential equations. Due to the specific singular choice of weight functions, which is needed to guarantee the interpolation, there arises a problem of finding the inverse of the occurring singular matrix. The inverse is carried out using a regularization of weight functions. It turns out that a stable inverse is obtained by considering the vanishing regularization parameter.

Moreover, the use of this perturbation technique allows the correct evaluation of all necessary derivatives in interpolation points at a reasonable cost.

Unlike standard kernel functions used in EFGM, RKPM, etc., the singular kernel functions lead to really interpolating functions which satisfy the Kronecker‐delta property. They can be used for enforcement of Dirichlet boundary conditions when solving boundary value problems.

Solution to a model BVP as well as an experimental convergence study of the method to analytical solutions, confirming the mathematical derivations, are given. Copyright © 2006 John Wiley & Sons, Ltd.
Estrogen receptor β as a therapeutic target for promoting neurogenesis and preventing neurodegeneration
Authors: Zhao Liqin , Brinton Roberta Diaz
Published: February 2006

Both estrogen receptor (ER) subtypes, ERα and ERβ, are expressed throughout the brain of both rodents and humans. Analyses from our laboratory and others reveal that both ERα and ERβ can contribute to estrogen‐induced protection against neurodegenerative insults. ERβ plays a key role in regulating brain development and estrogen‐induced promotion of neurogenesis and memory. These findings suggest that targeting ERβ could generate safe and effective therapeutics to promote neuronal defense mechanisms and to maintain cognitive function, while simultaneously reducing adverse effects in reproductive organs such as breast and uterus. A number of naturally occurring ERβ selective phytoestrogens have been identified and multiple structurally diverse ERβ selective ligands have been synthesized. A comparison of the models of complexes between selective agonists and either ERα or ERβ reveals that two variant amino acid residues in the ligand binding site, Leu384 and Met421 in ERα, which are replaced with Met336 and Ile373, respectively, in ERβ, are the key molecular constituents underlying the binding of selective ligands to either ER subtype. Development of an ERβ brain‐selective estrogen receptor modulator, in particular a natural source formulation, has great potential benefit for peri‐ and post‐menopausal women who face age‐associated cognitive decline and neurodegeneration. In addition, an ERβ selective formulation might promote neuronal defense mechanisms and cognition in men, while reducing the risk of prostate cancer. Drug Dev. Res. 66:103–117, 2006. © 2006 Wiley‐Liss, Inc.
Estrogen replacement and cognition in postmenopausal women: effect of years since menopause on response to treatment
Authors: Dunkin Jennifer , Rasgon Natalie , Zeller Michelle , Wagner‐Steh Kristi , David Steven , Altshuler Lori , Rapkin Andrea
Published: February 2006

The use of estrogen replacement therapy (ERT) to treat or prevent cognitive changes has become highly controversial in the past several years. Recent studies have suggested that participant age might play an important role in clinical response to estrogen. Specifically, previous studies have suggested that the age of participants might be a critical factor in drug response in that younger or more recently postmenopausal women might benefit more than older women and might help to explain conflicting results of other studies. In the present study, we used a randomized, placebo‐controlled design and a transdermal estrogen preparation composed of 17‐beta estradiol. Twenty depressed subjects and 17 age‐matched nondepressed control subjects were tested. A neuropsychological battery was administered at baseline and after completion of the 10‐week trial, and test scores were grouped into four composite scores using psychometric techniques. Baseline to follow‐up change was analyzed using repeated measures analysis of covariance. Results indicate that, while little overall beneficial effect of estrogen was found, years since menopause was significantly related to change in executive functioning in the estrogen group, but not the placebo group. Thus, more recently postmenopausal women demonstrated greater positive change than older women. This finding occurred in both the depressed sample and the control subjects. These results suggest that reproductive events are related to the clinical response to ERT, and that it might be worthwhile re‐analyzing results of prior studies with this variable in mind. Drug Dev. Res. 66:150–159, 2006. © 2006 Wiley‐Liss, Inc.
17β‐ and 17α‐estradiol are non‐competitive inhibitors of dopamine uptake: implications for Parkinson's disease models and therapeutics
Authors: Dykens James A. , Wersinger Christophe , Sidhu Anita
Published: February 2006

Despite compelling literature documenting the cyto‐ and neuro‐protective activities of various estrogens in a wide variety of cell and animal models, several large clinical trials of hormone replacement therapies have failed to detect such beneficial responses in humans. To some degree, this failure stems from profound hormonal responses that counterbalance the protective effects. This limitation could be circumvented by the development of less hormonally active estrogen analogs that retain the cytoprotective activities of the parental hormones. For example, 17α‐estradiol (17α‐E2) is at least 200‐fold less active than 17β‐estradiol (17β‐E2) as a transactivating hormone, yet it is equipotent as a cytoprotectant in many cell types exposed to a variety of stressors, such as amyloid toxicity, serum withdrawal, oxidative stress, and glutamate excitotoxicity. Both estradiol isomers stabilize mitochondrial function under pathogenic conditions, and both have shown efficacy in animal models of stroke. The results for models of Parkinson's disease differ, and 17β‐E2, but not 17α‐E2, has been reported previously to provide neuroprotection against MPTP toxicity. However, such findings must be regarded in light of reports that 17β‐E2 impedes cellular uptake of MPTP by the dopamine transporter (DAT), thereby forestalling development of the lesion rather than providing authentic cytoprotection. We report here that both 17α‐E2 and 17β‐E2 show classical, non‐competitive, inhibition of dopamine uptake by the human DAT (hDAT) transfected into Ltk− mouse fibroblasts, HEK293 human embryonic kidney cells, and SH‐SY5Y human neuroblastoma cells. IC50 values vary slightly with cell type, but are 400 and 70 nM for 17α‐E2 and 17β‐E2, respectively, in SH‐SY5Y cells. We also evaluated 17α‐E2 in the 6‐OH‐dopamine (6‐OHDA) model of PD, where toxin uptake occurs via the DAT. In these studies, treatment with estrogen was delayed for 6 hr after unilateral intrastriatal 6‐OHDA injection to allow for toxin uptake. After 6 hr, a loading dose of 17α‐E2 (100 µg/kg in sesame oil) was injected s.c., accompanied by implanting of a sustained release silastic device. After 21 days, animals treated with 17α‐E2 showed significant improvements in both gait asymmetry and apo‐morphine induced rotational defects. These positive results encourage evaluation of 17α‐E2 in a host of neurodegenerative diseases. Drug Dev. Res. 66:160–171, 2006. © 2006 Wiley‐Liss, Inc.
Low‐loss athermal AWG module with high reliability
Authors: Hasegawa Junichi , Nara Kazutaka
Published: February 2006

When building future optical communication networks, athermal and low loss properties continue to be essential demands for arrayed waveguide grating (AWG) which plays the role of a wavelength multiplexer/demultiplexer. To respond to these demands, we developed a low‐loss, 200‐GHz 16‐channel athermal AWG module from low loss techniques and original athermal techniques. The module we developed achieved an insertion loss below 1.4 dB, a center wavelength fluctuation less than ±0.015 nm in all modules in a temperature range from −5°C to 70°C, and an insertion loss fluctuation less than ±0.1 dB. Furthermore, we confirmed that this module has very high reliability from the results of a long‐term reliability test lasting 5000 hours. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 89(3): 26–33, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20213
Parallel remeshing of unstructured volume grids for CFD applications
Authors: Tremel U. , Sørensen K. A. , Hitzel S. , Rieger H. , Hassan Oubay , Weatherill Nigel P.
Published: February 2006

This paper presents a new approach towards the parallel local remeshing of unstructured tetrahedral grids on distributed memory parallel computers based on the message passing paradigm (MPI). The overall remeshing approach consisting of the parallel determination of the regions to be remeshed and the parallel local surface and volume remeshing is described in detail. An application of the remeshing algorithms in a time‐accurate simulation of bodies in relative motion demonstrates the capabilities of the approach. Copyright © 2006 John Wiley & Sons, Ltd.
Regulator of G‐protein signaling (RGS) proteins differentially control chondrocyte differentiation
Authors: Appleton C. Thomas G. , James Claudine G. , Beier Frank
Published: February 2006

Control of chondrocyte differentiation is attained, in part, through G‐protein signaling, but the functions of the RGS family of genes, well known to control G‐protein signaling at the Gα subunit, have not been studied extensively in chondrogenesis. Recently, we have identified the Rgs2 gene as a regulator of chondrocyte differentiation. Here we extend these studies to additional Rgs genes. We demonstrate that the Rgs4, Rgs5, Rgs7, and Rgs10 genes are differentially regulated during chondrogenic differentiation in vitro and in vivo. To investigate the roles of RGS proteins during cartilage development, we overexpressed RGS4, RGS5, RGS7, and RGS10 in the chondrogenic cell line ATDC5. We found unique and overlapping effects of individual Rgs genes on numerous parameters of chondrocyte differentiation. In particular, RGS5, RGS7, and RGS10 promote and RGS4 inhibits chondrogenic differentiation. The identification of Rgs genes as novel regulators of chondrogenesis will contribute to a better understanding of both normal cartilage development and the etiology of chondrodysplasias and osteoarthritis. © 2006 Wiley‐Liss, Inc.
Dynamics of vitellogenin synthesis in juvenile giant freshwater prawn Macrobrachium rosenbergii
Authors: Jayasankar Vidya , Jasmani Safiah , Tsutsui Naoaki , Aida Katsumi , Wilder Marcy N.
Published: February 2006

The dynamics of vitellogenin (Vg) mRNA expression and patterns of Vg and vitellin distribution in the hepatopancreas and ovary of juvenile Macrobrachium rosenbergii were examined using real‐time RT‐PCR and immunohistochemical methods. Eyestalk ablation was seen to induce rapid development of the gonads and Vg synthesis in females. In the female hepatopancreas, Vg mRNA expression was observed several days following ablation, after which levels increased gradually with increasing gonadosomatic index (GSI). Vitellin accumulation in the oocytes also increased with increasing Vg mRNA synthesis; expression was however negligible in the ovary. Hemolymph Vg levels in females ranged from 0.04 to 2.2 mg/ml. SDS PAGE/Western blotting analysis of hemolymph samples revealed that juvenile Vg was composed of 199 and 90 kDa subunits; the 102 kDa subunit present in adult female Vg (Okuno et al., 2002. J Exp Zool 292:417–429) could not be detected at any stage of vitellogenesis in juveniles. Vg was not detectable in non‐ablated juveniles. The results of this study confirmed that the mode of involvement of eyestalk factors in regulating vitellogenesis is intrinsic to both juveniles and adults, and that a basic pattern of Vg synthesis and processing is conserved. However, the fact that juveniles are not able to produce the same Vg levels observed in adult females, and do not reach high GSI levels culminating in spawning suggests that other factors and physiological conditions specific to adult females are necessary to demonstrate full reproductive ability. J. Exp. Zool. 305A, 2006. © 2006 Wiley‐Liss, Inc.
Stable transmission and expression of the hepatitis B virus total genome in hybrid transgenic mice until F10 generation
Authors: Bagis Haydar , Arat Sezen , Mercan Hande Odaman , Aktoprakligil Digdem , Caner Muge , Turanli Eda Tahir , Baysal Kemal , Turgut Gazi , Sekmen Sakir , Cirakoglu Beyazit
Published: February 2006

The aim of the present study was the generation of transgenic mice carrying the complete Hepatitis B Virus (HBV) genome and investigation of the presence of Hepatitis B surface antigen (HBsAg) expression through successive generations. Transgenic mice were generated by microinjecting HBV genome into fertilized eggs. Integration and expression of HBsAg in transgenic mice were analyzed by genomic DNA PCR, Southern and slot blots and enzyme‐linked immunosorbent assay (ELISA). Expression was also confirmed by Western blotting and RT‐PCR. Histological changes in liver tissue of transgenic mice were examined by HE staining. The HBV genome was transmitted to the F10 generation and the presence of HBV X gene transcripts was confirmed by RT‐PCR analysis using liver cDNAs from the F10 generation mice. During an observation period of 2.5 years, mice were sacrificied and their organs subjected to histopathological examination. In the liver, slight histopathologic alterations were observed but none of these lineages had any hepatocellular carcinoma (HCC). HBV DNA can be stably transmitted and expressed in the transgenic mice until F10 generation. However, although we showed the presence of X gene transcripts in liver tissues of F10 generation mice by RT‐PCR in these animals, long‐term expression of the HBV complete genome and expression of X protein in hepatocytes did not cause neoplasia during the life span and HCC. These transgenic mice should be useful for detailed studies of the replication and expression of HBV and for physiological studies of HBV genome. J. Exp. Zool. 305A, 2006. © 2006 Wiley‐Liss, Inc.
15N NMR spectra of some ionic liquids based on 1,3‐disubstituted imidazolium cations
Authors: Lyčka Antonín , Doleček Roman , Šimûnek Petr , Macháček Vladimír
Published: February 2006

15N NMR spectra of twelve neat ionic liquids derived from 1,3‐disubstituted imidazolium salts were measured, and effects of nitrogen atoms substitution, type of anions and influence of solvents used for dilution of neat ionic liquids were studied. Changes in charge distribution are discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Explicit empirical relation for the monthly average cell‐temperature performance ratio of photovoltaic arrays
Authors: Franghiadakis Y. , Tzanetakis P.
Published: February 2006

An empirical relation is derived that allows accurate estimates of the influence of cell temperature variations on the output of a photovoltaic array. Monthly average cell‐temperature performance ratios, PRT , can be calculated from the latitude of the site and monthly average values of solar irradiance, air temperature and wind speed. The derivation of the empirical relation for PRT is based on intermediate empirical relations and approximations established by the analysis of a database from stations located at various latitudes and having diverse climatic characteristics. The accuracy of the relation is tested against PRT calculations from short‐interval data available in the database. Copyright © 2006 John Wiley & Sons, Ltd.
Highly‐efficient Cd‐free CuInS2 thin‐film solar cells and mini‐modules with Zn(S,O) buffer layers prepared by an alternative chemical bath process
Authors: Ennaoui A. , Bär M. , Klaer J. , Kropp T. , Sáez‐Araoz R. , Lux‐Steiner M. Ch.
Published: February 2006

Recent progress in fabricating Cd‐ and Se‐free wide‐gap chalcopyrite thin‐film solar devices with Zn(S,O) buffer layers prepared by an alternative chemical bath process (CBD) using thiourea as complexing agent is discussed. Zn(S,O) has a larger band gap (Eg = 3·6–3·8 eV) than the conventional buffer material CdS (Eg = 2·4 eV) currently used in chalcopyrite‐based thin films solar cells. Thus, Zn(S,O) is a potential alternative buffer material, which already results in Cd‐free solar cell devices with increased spectral response in the blue wavelength region if low‐gap chalcopyrites are used. Suitable conditions for reproducible deposition of good‐quality Zn(S,O) thin films on wide‐gap CuInS2 (‘CIS’) absorbers have been identified for an alternative, low‐temperature chemical route. The thickness of the different Zn(S,O) buffers and the coverage of the CIS absorber by those layers as well as their surface composition were controlled by scanning electron microscopy, X‐ray photoelectron spectroscopy, and X‐ray excited Auger electron spectroscopy. The minimum thickness required for a complete coverage of the rough CIS absorber by a Zn(S,O) layer deposited by this CBD process was estimated to ∼15 nm. The high transparency of this Zn(S,O) buffer layer in the short‐wavelength region leads to an increase of ∼1 mA/cm2 in the short‐circuit current density of corresponding CIS‐based solar cells. Active area efficiencies exceeding 11·0% (total area: 10·4%) have been achieved for the first time, with an open circuit voltage of 700·4 mV, a fill factor of 65·8% and a short‐circuit current density of 24·5 mA/cm2 (total area: 22·5 mA/cm2). These results are comparable to the performance of CdS buffered reference cells. First integrated series interconnected mini‐modules on 5 × 5 cm2 substrates have been prepared and already reach an efficiency (active area: 17·2 cm2) of above 8%. Copyright © 2006 John Wiley & Sons, Ltd.
Annealing effects on the photoresponse of TiO2 nanotubes
Authors: Ghicov Andrei , Tsuchiya Hiroaki , Macak Jan M. , Schmuki Patrik
Published: February 2006

The present work investigates the influence of different annealing treatments on the photoresponse of electrochemically formed TiO2 nanotubes. The “as prepared” TiO2 nanotube layers have an amorphous structure and show a comparably low photocurrent magnitude. Annealing the tubes in air or dry Ar at 450 °C converts the structure to anatase and increases strongly the photocurrent conversion efficiencies. Significant differences between annealing in air and in dry Ar were found. Annealing in Ar results in green layers that show lower photon to current efficiencies than the layers annealed in air. Extended annealing in Ar at 450 °C leads to morphological changes of the nanotube structure. These differences in the behaviour (photoresponse and mechanical stability) are attributed to the reductive nature of the Ar environment (leading to a partial reduction and vacancy formation). (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cohomologie des groupes et corps d’invariants multiplicatifs tordus
Authors: Barge J.
Published: February 2006

We give a cohomological calculation of the unramified Brauer group of a field of invariants under a twisted multiplicative action of a finite group.
Volume-preserving mean curvature flow of rotationally symmetric surfaces
Authors: Athanassenas Maria
Published: February 2006

A rotationally symmetric n-dimensional surface in

{\Bbb R}^{n+1}

, of enclosed volume V and with boundary in two parallel planes, is evolving under volume-preserving mean curvature flow. For large volume V, we obtain gradient and curvature estimates, leading to long-time existence of the flow, and convergence to a constant mean curvature surface.
Tilings and finite energy retractions of locally symmetric spaces
Authors: Saper L.
Published: February 2006

Let

\Gamma \backslash \overline{X}

be the Borel-Serre compactifiction of an arithmetic quotient

\Gamma \backslash X

of a symmetric space of noncompact type. We construct natural tilings

\Gamma \backslash \overline{X} = \coprod _P \Gamma \backslash \overline{X}_P

(depending on a parameter b) which generalize the Arthur-Langlands partition of

\Gamma \backslash X

. This is applied to yield a natural piecewise analytic deformation retraction of

\Gamma \backslash \overline{X}

onto a compact submanifold with corners

\Gamma \backslash X _0 \subset \Gamma \backslash X

. In fact, we prove that

\Gamma \backslash X _0

is a realization (under a natural piecewise analytic diffeomorphism) of

\Gamma \backslash \overline{X}

inside the interior

\Gamma \backslash X

. For application to the theory of harmonic maps and geometric rigidity, we prove this retraction and diffeomorphism have finite energy except for a few low ranks examples. We also use tilings to give an explicit description of a cofinal family of neighborhoods of a face of

\Gamma \backslash \overline{X}

, and study the dependance of tilings on the parameter b and the degeneration of tilings.
The decomposition of 3-dimensional Poincaré complexes
Authors: Crisp J.
Published: February 2006

We show that if the fundamental group of an orientable PD3-complex has infinitely many ends then it is either a proper free product or virtually free of finite rank. It follows that every PD3-complex is finitely covered by one which is homotopy equivalent to a connected sum of aspherical PD3-complexes and copies of

S^1 \times S^2

. Furthermore, it is shown that any torsion element of the fundamental group of an orientable PD3-complex has finite centraliser.
A note on degenerate corank-one singularities of integrable Hamiltonian systems
Authors: Zung Nguyen Tien
Published: February 2006

We prove that, in a neighborhood of a corank-1 singularity of an analytic integrable Hamiltonian system with n degrees of freedom, there is a locally-free analytic symplectic

{\Bbb T}^{n-1}

-action which preserves the moment map, under some mild conditions. This result allows one to classify generic degenerate corank-one singularities of integrable Hamiltonian systems. It can also be applied to the study of (non)integrability of perturbations of integrable systems.
csp2B: A Practical Approach to Combining CSP and B
Authors: Butler Michael
Published: February 2006

This paper describes the tool csp2B, which provides a means of combining CSP-like descriptions with standard B specifications. The notation of CSP provides a convenient way of describing the order in which the operations of a B machine may occur. The function of the tool is to convert CSP-like specifications into standard machine-readable B specifications, which means that they may be animated and appropriate proof obligations may be generated. Use of csp2B means that abstract specifications and refinements may be specified purely using CSP or using a combination of CSP and B. The translation is justified in terms of an operational semantics.
Evolutionary and population dynamics of host–parasitoid interactions
Authors: Tuda M. , Bonsall Michael B.
Published: February 2006

The role of evolutionary dynamics in understanding host–parasitoid interactions is interlinked with the population dynamics of these interactions. Here, we address the problems in coupling evolutionary and population dynamics of host–parasitoid interactions. We review previous theoretical and empirical studies and show that evolution can alter the ecological dynamics of a host–parasitoid interaction. Whether evolution stabilizes or destabilizes the interaction depends on the direction of evolutionary changes, which are affected by ecological, physiological, and genetic details of the insect biology. We examine the effect of life history correlations on population persistence and stability, embedding two types, one of which is competitively inferior but superior in encapsulation (for parasitoid, virulence), in a Nicholson–Bailey model with intraspecific resource competition for host. If a trade‐off exists between intraspecific competitive ability and encapsulation (or virulence, as a countermeasure) in both the host and parasitoid, the trade‐off or even positive correlation in the parasitoid is less influential to ecological stability than the trade‐off in the host. We comment on the bearing this work has on the broader issues of understanding host–parasitoid interactions, including long‐term biological control.
An experimental analysis of the relationship between species combination and community persistence
Authors: Mitsunaga T. , Fujii Koichi
Published: February 2006

Among many stabilizing factors for community dynamics, nonlinear biological interactions such as type III functional response have been widely considered to be major characteristics. However, most experimental biological communities employed so far had quite simple structures. Therefore, the possibility that the conclusions in earlier studies were dependent on simple community structure is undeniable. In this study, using a multiple‐species experimental community, we evaluated which combinations of component species and what kinds of interspecific interactions allow communities to persist and how these contribute to community persistence. We conducted experimental communities using two species of beans, the adzuki bean (Vigna angularis) and the red kidney bean (Phaseolus vulgaris), two species of bean weevils, the Mexican bean weevil (Zabrotes subfasciatus, Coleoptera: Bruchidae) and adzuki bean weevil (Callosobruchus chinensis, Coleoptera: Bruchidae), and two species of parasitic wasp, Heterospilus prosopidis (Hymenoptera: Braconidae) and Anisopteromalus calandrae (Hymenoptera: Pteromalidae). The outcome of multiple‐generation experimental communities was explained by the characteristics of component species obtained from short‐term experiments. In our two resources–two herbivores–one carnivore system, the strong density‐dependent attack ability of one parasitic wasp species (A. calandrae) led to the extinction of C. chinensis. On the other hand, the weak density‐dependent attack ability of the other parasitic wasp species (H. prosopidis) led to system persistence. Our overall results show that, in a multiple‐species community, the combination of species itself is more important for community persistence than are the characteristics of the particular species.
Patterns in the structure of grassland butterfly communities along a gradient of human disturbance: further analysis based on the generalist/specialist concept
Authors: Kitahara M. , Sei K. , Fujii K.
Published: February 2006

Kitahara and Fujii, in 1994, analyzed the butterfly communities along a gradient of human disturbance by applying the generalist/specialist concept. Butterfly species were classified into generalist or specialist species based on their voltinism (seasonal time dimension) and potential larval resource breadth (food dimension). The community structure and species composition showed the systematic changes along the gradient. To verify the generality of those trends, we monitored five grassland butterfly communities with varying degrees of human disturbance twice a month during 1985 by the line transect method at the foot of Mt. Fuji, central Japan, and analyzed their structure in a manner similar to that employed by Kitahara and Fujii. Most results were consistent with the patterns recognized by Kitahara and Fujii. The route (community) order based on increasing human disturbance was strongly and negatively correlated with butterfly species richness but with neither butterfly species diversity (H′) nor evenness (J′). Also, the degree of human disturbance was significantly and negatively correlated with the number of specialist species, but not with that of generalists, in a community. Butterfly species richness was more strongly correlated with the number of specialist species than with that of generalists. Our analyses also showed that the generalist species were distributed more widely over the communities than were the specialists. However, in contrast to the trend revealed by Kitahara and Fujii, there was no significant difference in the population densities and in the spatial population variability between the two species groups. As a whole, our analyses confirmed the consistency of most community patterns detected by Kitahara and Fujii. The causes of the inconsistencies in some patterns were thought to be mainly the present habitat conditions with a relatively short growing season at high altitudes.
Effects of nonhost and host plants on insect herbivory covarying with plant size in the cruciferous plant Turritis glabra
Authors: Masumoto T. , Sunahara T. , Suzuki N.
Published: February 2006

Correlation between plant size and reproductive output may be modified by herbivory in accordance with host plant density and the presence of nonhost plants. To elucidate the effects of nonhost plant density and host plant density on the intensity of herbivory and reproductive output of the host plant in relation to plant size under natural conditions, we investigated the abundance of three lepidopteran insects, Plutella maculipennis, Anthocharis scolymus, and Pieris rapae the intensity of herbivory, and fruit set of their host plant, Turritis glabra (Cruciferae). To elucidate the effects of nonhost and host plant density, we selected four categories of plots under natural conditions: low density of nonhost and high density of host plants; low density of both nonhost and host plants; high density of both nonhost and host plants; and high density of nonhost and low density of host plants. The plant size indicated by stem diameter was a good predictor of the abundance of all herbivorous species. The effects of density of nonhost and host plants on the abundance of insects varied among species and stages of insects. As the abundance of insects affected the intensity of herbivory, herbivory was more apparent on larger host plants in plots with low density of both nonhost and host plants. Consequently, the correlation between plant size and the number of fruits disappeared in low plots with density of both nonhost and host plants. In this T. glabra– herbivorous insect system, the density of nonhost plants and host plants plays an important role in modifying the relationship between plants and herbivores under natural conditions.
Should aphids attract or repel ants? Effect of rival aphids and extrafloral nectaries on ant–aphid interactions
Authors: Sakata H. , Hashimoto Y.
Published: February 2006

Among plants and herbivores, two types of conflicts occur in relation to mutualism with ants: one is competition for ant mutualism among myrmecophilous herbivores and plants, and the other is the conflict whether to attract or repel ants between myrmecophiles and nonmyrmecophiles that are damaged by ants. We investigated the extent to which two species of aphids (Megoura crassicauda and Aphis craccivora) and extrafloral nectaries on their host plant (Vicia faba var. minor) interact with one another for their relationships with ants. We designed an experiment where ants can choose to visit seedlings colonized by (1) M. crassicauda, (2) A. cracivora, (3) both aphid species, or (4) neither aphid species. Ants preferred A. craccivora to extrafloral nectaries and avoided tending M. crassicauda. We also analyzed the population growth of each aphid when it coexists with (1) ants, (2) the other aphid species, (3) ants and the other aphid species, or (4) neither of them. Under ant‐free conditions, we detected an exploitative competition between the two aphid species. The ants had no significant effect on the population of A. craccivora, whereas they had negative effects on the population growth of M. crassicauda by attacking some individuals. When both aphids coexisted, M. crassicauda suffered ant attack more intensely because A. craccivora attracted more ants than extrafloral nectaries despite ant‐repelling by M. crassicauda. On the other hand, the ants benefited A. craccivora by eliminating its competitor. To avoid ant attack, aphids may have been selected either to be more attractive to ants than other sympatric sugar sources or to repel the ants attracted to them. We hypothesize that competition among sympatric sugar sources including rival aphids and extrafloral nectaries is a factor restricting aphids to be myrmecophilous.
Causes of cyclicity of Epirrita autumnata (Lepidoptera, Geometridae): grandiose theory and tedious practice
Authors: Ruohomäki K. , Tanhuanpää M. , Ayres M. P. , Kaitaniemi P. , Tammaru T. , Haukioja E.
Published: February 2006

Creating multiyear cycles in population density demands, in traditional models, causal factors that operate on local populations in a density‐dependent way with time lags. However, cycles of the geometrid Epirrita autumnata in northern Europe may be regional, not local; i.e., successive outbreaks occur in different localities. We review possible causes of cycles of E. autumnata under both local and regional scenarios, including large‐scale synchrony. Assuming cyclicity is a local phenomenon, individual populations of E. autumnata display peaks but populations all over the outbreak range fluctuate in synchrony. This concept assumes that the peaks at most localities are so low that they do not lead to visible defoliation and easily remain unnoticed. In this scenario, populations are able to start recovery a few years after the crash, i.e., at the time of the mitigation of detrimental delayed density‐dependent factors, such as delayed inducible resistance of the host plant or parasitism. In that case, the same factors that lead to crashes also explain the periodicity of cyclic fluctuations. According to the regional cyclicity scenario, different factors can be important in different phases of the cycle. The key is to identify the factors that tend to produce outbreaks with a periodicity of about 10 years. Initiation of the increase phase seems to coincide with maxima in sunspot activity, but causal connections remain unclear. Climatic factor(s) associated with the solar cycle could contribute to the large‐scale geographic synchrony.