bluuebunny/crossref_metadata_2025 huggingface dataset:
Fragment‐based local statistical potentials derived by combining an alphabet of protein local structures with secondary structures and solvent accessibilities
Authors: Li Quan , Zhou Changhai , Liu Haiyan
Published: August 2008

General and transferable statistical potentials to quantify the compatibility between local structures and local sequences of peptide fragments in proteins were derived. In the derivation, structure clusters of fragments are obtained by clustering five‐residue fragments in native proteins based on their conformations represented by a local structure alphabet (de Brevern et al., Proteins 2000;41:271–287), secondary structure states, and solvent accessibilities. On the basis of the native sequences of the structurally clustered fragments, the probabilities of different amino acid sequences were estimated for each structure cluster. From the sequence probabilities, statistical energies as a function of sequence for a given structure were directly derived. The same sequence probabilities were employed in a database‐matching approach to derive statistical energies as a function of local structure for a given sequence. Compared with prior models of local statistical potentials, we provided an integrated approach in which local conformations and local environments are treated jointly, structures are treated in units of fragments instead of individual residues so that coupling between the conformations of adjacent residues is included, and strong interdependences between the conformations of overlapping or neighboring fragment units are also considered. In tests including fragment threading, pseudosequence design, and local structure predictions, the potentials performed at least comparably and, in most cases, better than a number of existing models applicable to the same contexts indicating the advantages of such an integrated approach for deriving local potentials and suggesting applicability of the statistical potentials derived here in sequence designs and structure predictions. Proteins 2009. © 2008 Wiley‐Liss, Inc.
MINOES: A new approach to select a representative ensemble of structures in NMR studies of (partially) unfolded states. Application to Δ25‐PYP
Authors: Krzeminski Mickaël , Fuentes Gloria , Boelens Rolf , Bonvin Alexandre M.J.J.
Published: August 2008

In nature, some proteins partially unfold under specific environmental conditions. These unfolded states typically consist of a large ensemble of conformations; their proper description is therefore a challenging problem. NMR spectroscopy is particularly well suited for this task: information on conformational preferences can be derived, for example, from chemical shifts or residual dipolar couplings. This information, which is measured as a time‐ and ensemble‐average, can be used to model these states by generating large ensembles of conformations. The challenge is then to select a minimum representative set of conformations out of a large ensemble to represent the unfolded state. We have developed for this purpose an algorithm called MINOES (MINimum Optimal Ensemble Selection), which is based on an iterative procedure based on a driven expansion/contraction selection process. MINOES aims at selecting an optimal and minimal ensemble of conformations that, on average, maximizes the agreement between back‐calculated and experimental (NMR) data, without any a‐priori assumption about the required ensemble size. This approach is demonstrated by modeling the partially unfolded state of a deletion mutant of the Photoactive Yellow Protein, Δ25‐PYP, which has been previously characterized by NMR (Bernard et al., Structure 2005;13:953–962). Proteins 2009. © 2008 Wiley‐Liss, Inc.
Ab initio analysis of monomers and dimers of trialkylphosphine oxides: Structural and thermodynamic stability
Authors: Malaspina Thaciana , Costa Luciano T. , Fileti Eudes E.
Published: August 2008

Structural and thermodynamic stabilities of monomers and dimers of trialkylphosphine oxides (TRPO) were studied using quantum chemistry calculations. Density functional theory calculations were carried out and the structures of four TRPO have been determined: TMPO (methyl; R = CH3), TEPO (ethyl; R = CH3CH2), TBPO (n‐butyl; R = CH3(CH2)3), and TOPO (n‐octyl; R = CH3(CH2)7). TRPO homodimers were investigated considering two isomeric possibilities for each dimer. Relative binding energies and the enthalpic and entropic contributions to the Gibbs free energy were calculated for all dimers. The formation of dimers from the individual monomeric TRPO species as a function of temperature was also analyzed. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Computational studies on the spectroscopic properties of the 2‐pyridylpyrazolate‐based platinum(II) complexes with modified pyrazolate fragment
Authors: Bai Fu‐Quan , Zhou Xin , Liu Tao , Zhao Guang‐Jin , Zhang Jian‐Po , Zhang Hong‐Xing
Published: August 2008

Electronic structures and spectroscopic properties of a series of platinum(II) complexes based on the 2‐pyridylpyrazolate ligand with modified pyrazolate fragment have been studied by the time‐dependent density functional theory (TD‐DFT) calculations. The ground‐ and excited‐state structures were optimized by the DFT and single‐excitation configuration interaction (CIS) methods, respectively. The calculated structures and spectroscopic properties are in agreement with the corresponding experimental results. The results of the spectroscopic investigations revealed that the lowest‐energy absorptions have 1,3MLCT/1,3ILCT mixing characters. When the electron‐withdrawing groups (CF3, C3F7) are introduced into the pyrazolate fragment, the lowest‐energy absorptions are blue‐shifted compared with that without substituents on the pyrazolate fragment, while the opposite case is observed for the electron‐donating groups (Me, tBu, etc.). Otherwise, the phosphorescent emissions of these complexes have the 3MLCT/3ILCT character and should be originated from the lowest‐energy absorptions. When the pyrazolate fragment is replaced by the indazole group, the HOMO and LUMO orbitals of the pyridyl‐indazolate ligand platinum(II) complexes have obvious π and π* orbital characters. Therefore, there is no evident MLCT character in the lowest energy absorption and emission. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Theoretical study on structures and stabilities of N4X (X = O, S, Se, Te) series
Authors: Guohua Zhang , Yongfang Zhao , Fengyou Hao , Pingxia Zhang , Xiudan Song
Published: August 2008

The stable and transition structures of N4X (X = O, S, Se, Te) series with singlet state are optimized with the ab initio (MP2) and density functional theory (B3LYP) methods using the 6‐311+G(d) basis set. The ring isomers are found to be the global minima for N4O, N4S, N4Se, and the chain isomer is the minimum for N4Te. The stabilities are studied by evaluating the dissociation barriers with respect to dissociation. The reactants and products connected by transition structures are determined by applying the intrinsic reaction coordinate (IRC) calculations. The C2v, C3v and ring isomers decompose into linear NNX and N2 molecules, however, the chain isomers decompose into cyclic N2X and N2 firstly. A new possible isomerization mechanism between the cyclic and linear structures of N2X series is studied. The cyclic structures of N2X convert into linear structures easily with the very low barriers. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Hepatitis C and renal transplantation: a review on historical aspects and current issues
Authors: Moghaddam Seyed Mohammadmehdi Hosseini , Alavian Seyed Moayed , Kermani Nahid Arjmand
Published: August 2008

Chronic liver disease has a significant impact on the survival of renal transplant recipients with an incidence rate of 4–38%. Approximately, 8–28% of renal transplant recipients die due to chronic liver disease. Hepatitis C seems to be the leading cause of chronic liver disease in kidney recipients. Hepatitis C virus (HCV) infection has a wide range of prevalence (2.6–66%) among renal transplant recipients living in different countries with great genotype diversity in different parts of the world. Nowadays, antiviral drugs are used for the management of hepatitis C. Because of graft‐threatening effects of some antiviral drugs used in HCV‐infected renal transplant recipients, we specifically focused on HCV treatment after renal transplantation. Treatment of post‐renal transplantation chronic liver disease with INF and ribavirin remains controversial. Anecdotal reports on post‐renal transplantation hepatitis C demonstrate encouraging findings. This review summarises the most current information on diagnosis, treatment, prognosis, complications as well as the new aspects of treatment in HCV‐infected renal transplant recipients. HCV belongs to the family of Flaviviridae, genus Hepacivirus. Copyright © 2008 John Wiley & Sons, Ltd.
The influence of human, livestock, and ecological features on the occurrence of genet (Genetta genetta): a case study on Mediterranean farmland
Authors: Galantinho Ana , Mira António
Published: August 2008

We have studied the relationship between occurrence patterns of the genet (Genetta genetta) and ecological, human, and livestock descriptors at the Monfurado Natura 2000 Site in southern Portugal. An information–theoretical model comparison (ITMC) was used to select the best models to explain the presence of the species, using data from 36 habitat patches. Variables that were included in the best models then were used in a variation partitioning procedure to determine the relative influence of each variable set on the presence of the genet. When considered together, all the variables captured 56.5% of the variance in genet occurrence within the study area. The set of ecological variables accounted for most of the explained variance (pure effect: 30.3%). In the best ecological model, the occurrence of the genet was positively related to the density of trees and shrubs in the dominant agro–silvo–pastoral system (montado), to soil organic matter, and to Shannon's index of vertical vegetation diversity. Human influence factors (pure effect: 4.8%) highlighted the negative relationship between the presence of the genet and the proportion of game‐estate areas. The group of livestock variables (pure effect: 8.5%) revealed that intermediate levels of grazing may promote the occurrence of the genet. Our results highlight the importance of variables directly related to agricultural management, and are meaningful because they allow for the prioritization of management decisions. In particular, the results draw attention to soil organic matter and grazing by sheep, which are important factors in soil conservation practices.
Age-related slowing of movement as basal ganglia dysfunction
Authors: Saling L. L. , Phillips J. G.
Published: August 2008

Attributions of age-related deficits in motor function to structural changes are compromised once the elderly exhibit lower error rates. This is because performance decrements observed in older adults are attributed to inferred strategic preferences for accuracy over speed. To understand genuine age differences in performance, we argue in the following theoretical paper that research needs to resolve methodological shortcomings and account for them within theoretical models of aging. Accounts of aging need to directly manipulate or control strategic differences in performance while assessing structural deficits. When this is done, age-related changes in motor control resemble the intermittencies of control seen in basal ganglia disorders. Given homologous circuitry in the basal ganglia, such observations could generalize to age-related changes in cognitive and emotional processes.
Batteries assessing health related fitness in the elderly: a brief review
Authors: Varela S. , Ayán C. , Cancela J. M.
Published: August 2008

Evaluation of physical functioning is a key issue in clinical geriatrics and in aging research. In recent years, different physical performance batteries in which individuals are asked to perform several tasks and are evaluated using different criteria have been designed and used in elderly populations. These batteries include different types of test which range from basic motor abilities to relevant everyday activities, depending on the construct area in the domain of physical function that must be measured. This paper reviews and classifies the main physical functioning batteries that can be found in the scientific field of aging research in order to provide knowledge on selection, administration, and interpretation of this indispensable assessment tools.
Toward Understanding Molecular Mechanisms of Abiotic Stress Responses in Rice
Authors: Gao Ji-Ping , Chao Dai-Yin , Lin Hong-Xuan
Published: August 2008

Plants have evolved delicate mechanisms to cope with environmental stress. Following exposure to environmental stimuli, extracellular signals are perceived and transmitted through signal transduction cascades. Upon receipt and transmission of the signals, a number of stress-related genes are induced, leading to stress adaptation in plant cells. Rice, which is a critical food grain for a large portion of the world’s population, is frequently impacted by several abiotic stressors, the most important of which are drought, salinity, and cold. Exposure to environmental conditions outside of acceptable tolerance ranges can negatively affect rice growth and production. In this paper, a review of rice responses to abiotic stress is presented, with particular attention to the genes and pathways related to environmental stress tolerance. It is apparent that, while progress has been made in identifying genes involved in stress adaptation, many questions remain. Understanding the mechanisms of stress response in rice is important for all research designed to develop new rice varieties with improved tolerance.
The Cornucopia of Small RNAs in Plant Genomes
Authors: Simon Stacey A. , Zhai Jixian , Zeng Jia , Meyers Blake C.
Published: August 2008

Regulatory small RNAs (approximately 20 to 24 nt in length) are produced through pathways that involve several key evolutionarily conserved protein families; the variants of these proteins found in plants are encoded by multigene families and are known as Dicer-like, Argonaute, and RNA-dependent RNA polymerase proteins. Small RNAs include the well-known classes of microRNAs (miRNAs, ~21 nt) and the small-interfering RNAs (siRNAs, ~24 nt). Both of these types of molecules are found across a broad set of eukaryotic species, although the siRNAs are a much larger and more diverse class in plants due to the abundance of heterochromatic siRNAs. Well-studied species such asArabidopsishave provided a foundation for understanding in rice and other species how small RNAs function as key regulators of gene expression. In this paper, we review the current understanding of plant small RNA pathways, including the biogenesis and function of miRNAs, siRNAs, trans-acting siRNAs, and heterochromatic siRNAs. We also examine the evolutionary relationship among plant species of both their miRNAs and the key enzymatic components of the small RNA pathways. Many of the most recent advances in describing small RNAs have resulted from advances in sequencing technologies used for identifying and measuring small RNAs, and these technologies are discussed. Combined with the plethora of genetic tools available to researchers, we expect that the continued elucidation of the identity and functions of plant small RNAs will be both exciting and rewarding.
Rice Metabolomics
Authors: Oikawa Akira , Matsuda Fumio , Kusano Miyako , Okazaki Yozo , Saito Kazuki
Published: August 2008

Metabolomics is a recently developed technology for comprehensive analysis of metabolites in organisms. Plant metabolites that are produced for the growth, development, and chemical defense of plants against climatic alterations or natural predators are also useful to us as nutrients or medicines; hence, it is important to comprehend the amounts and varieties of plant metabolites. Besides providing an understanding of the metabolic state in plants under various circumstances, metabolomic techniques are applicable to the clarification of the functions of unknown genes by using natural variants or mutants of the target plants. Furthermore, a metabolomic approach might be useful in the breeding of crops, since valuable plant traits such as taste and yield are closely related to metabolic conditions. Here, we describe the methodology of metabolomics including sample extraction and preparation, metabolite detection, and data processing and analysis, and introduce the application of metabolomic studies to rice.
Negative and positive peer influence: Relations to positive and negative behaviors for African American, European American, and Hispanic adolescents
Authors: Padilla‐Walker Laura M. , Bean Roy A.
Published: August 2008

The purpose of the current study was to examine adolescents' perceptions of negative and positive peer influence (i.e., indirect peer association and direct peer pressure) as they related to adolescent behavior. Regression analyses were conducted using a sample of African American, European American, and Hispanic adolescents (N = 1659, M age = 16.06, SD = 1.10). The study found differences and similarities in relation to respondents' ethnicity vis‐à‐vis indirect peer association and adolescent behavior. Although few ethnic‐based differences occurred as a function of indirect negative peer association, indirect positive peer association was not as consistently or as strongly related to behaviors for minority youth as it was for European American youth.
The influence of a primary prevention program on eating‐related attitudes of Israeli female middle‐school students
Authors: Canetti Laura , Bachar Eytan , Gur Eitan , Stein Daniel
Published: August 2008

The present study aimed to assess the impact of a primary prevention program on eating‐related attitudes in 231 female 7th graders at baseline and following a six‐session prevention program. Fifty‐nine 7th grade control females received six unstructured lectures about adolescence. One hundred and three experimental students and 37 controls were re‐evaluated after one year. Among the participants in the prevention program, there was a significant post‐intervention and one‐year improvement in the total score of the eating‐related attitudinal Treatment Efficacy Scale (TES) and in several of its domains. Whereas no change occurred in the attitudes of the controls at post‐intervention, some improvement was shown in several TES domains after one year, compared to baseline. Attitudinal changes were significantly more favorable in the prevention program participants than in the controls both at post‐intervention and at one‐year follow‐up. These findings suggest that eating‐related attitudes of female middle‐school students may improve following a primary prevention program, with some of these improvements persisting after one year.
You're all grown up now: Termination of foster care support at age 18
Authors: Avery Rosemary J. , Freundlich Madelyn
Published: August 2008

This article considers the repercussions of discharging youth from foster care at age 18 based on recent research demonstrating that youth at this age are not developmentally prepared to live independently and have a continued need for strong social scaffolding during emerging adulthood. Drawing upon recent research findings, we make recommendations for changes to state and federal policy that provide youth transitioning from foster care an extension of federal/state financial and social support into the third decade of life. We argue for a re‐conceptualization of “independent living” as “interdependent living,” and recommend that policymakers require a permanent committed adult be identified for each youth prior to discharge from foster care.
Brief report: The defense mechanisms of homophobic adolescent males: A descriptive discriminant analysis
Authors: Lewis Andrew J. , White Jennifer
Published: August 2008

The study examined the role of defense mechanisms in homophobic attitudes of older male adolescents aged 17–18 years. A cross‐sectional survey collected data from final year high school students (N = 86) attending an all male school in a regional centre in Victoria, Australia. The school was identified by teachers as having a problematic culture of homophobic intolerance. Participants were divided into homophobic and non‐homophobic groups based on their scores on the Homophobia Scale Questionnaire. Discriminant analysis was conducted to identify the predictors that would best categorise students into those two groups on the basis of defense styles derived from the Defense Style Questionnaire‐40 (DSQ‐40). The strongest predictors of homophobia amongst defense styles were idealisation, denial, somatisation and devaluation accounting for 18.31%, 17.64%, 13.10% and 11.35% of the variance, respectively. Results generally supported the larger contribution of more immature defenses to higher levels of homophobia.
In vivotest of the vertical phase separation hypothesis: the display of major histocompatibility complex (MHC) class I molecules on membranes of B cells from mice fed high-fat diets
Authors: Shaikh Saame Raza , Boyle Sarah , Hua Jing , Li Zhiping , Edidin Michael
Published: August 2008

The membrane vertical phase separation hypothesis predicts that a decrease in plasma membrane acyl chain order will increase major histocompatibility complex (MHC) class I surface expression. The hypothesis is based on modification of plasma membrane acyl chain order in cell culture and has not been testedin vivo. In the present study, we isolated splenic B cells from C57/BL6 mice fed either a normal diet or high-fat diets enriched in SFA or MUFA and assayed for changes in plasma membrane acyl chain order and MHC class I surface expression. Plasma membranes of B cells from MUFA-fed mice had significantly decreased acyl chain order and increased headgroup order. The decrease in acyl chain order correlated with a significant increase in the acyl chain unsaturation of B cells from the MUFA-fed mice. MHC class I surface levels on B cells were not affected by the MUFA-rich diet. This study suggests that the membrane vertical phase separation hypothesis may have limited application in a physiologically relevant setting.
THE JOINT SIMILARITY PROBLEM FOR WEIGHTED BERGMAN SHIFTS
Authors: Ferguson Sarah H. , Petrovic Srdjan
Published: August 2008

We solve a joint similarity problem for pairs of operators of Foias–Williams/Peller type on weighted Bergman spaces. We show that for the single operator, the Hardy space theory established by Bourgain and Aleksandrov–Peller carries over to weighted Bergman spaces, by establishing the relevant weak factorizations. We then use this fact, together with a recent dilation result due to the first author and Rochberg, to show that a commuting pair of such operators is jointly polynomially bounded if and only if it is jointly completely polynomially bounded. In this case, the pair is jointly similar to a pair of contractions by Paulsen’s similarity theorem.

AMS 2000 Mathematics subject classification: Primary 47B35; 47B47
EMBEDDING ℐn IN A 2-GENERATOR INVERSE SUBSEMIGROUP OF ℐn+2
Authors: McAlister D. B. , Stephen J. B. , Vernitski A. S.
Published: August 2008

Given an integer $n$, we show that $\mathcal{I}_{n}$ embeds in a 2-generated subsemigroup of $\mathcal{I}_{n+2}$, which is an inverse semigroup. An immediate consequence of this result is the following, which is analogous to the case for groups and semigroups: every finite inverse semigroup may be embedded in a finite 2-generated semigroup which is an inverse semigroup.

AMS 2000 Mathematics subject classification: Primary 20M18. Secondary 20M20
MAXIMAL FUNCTIONS AND SUBORDINATION FOR OPERATOR GROUPS
Authors: Blower Gordon
Published: August 2008

Let $E$ be a UMD Banach space, and $L$ a positive self-adjoint operator in $\mathrm{L}^2$ of Laplace type, for which the imaginary powers $L^{-\ri t}$ form a $C_0$-group of exponential growth $0\leq\alpha\lt \pi$ on $\mathrm{L}^p(E)$, where $1\lt p\lt\lt \infty$. Suppose $G(z)$ is holomorphic inside and on the boundary of the sector $\{z:z\neq0,\ |\arg z|\leq\phi\}$, and $z^\kappa G(z)\rightarrow0$ uniformly as $z\rightarrow\infty$ for some $\kappa\gt0$ and $\phi\gt\alpha$. Then $G(tL)$ $(t \gt0)$ defines a bounded family of linear operators on $\mathrm{L}^p(E)$; and the maximal operator $f\mapsto\sup_{t \gt 0}\|G(tL)f\|_E$ is bounded on the domain of $\log L$. The proof uses transference methods. These hypotheses hold for the maximal solution operators for the heat, wave and Schrödinger equations, and for Cesàro sums.

AMS 2000 Mathematics subject classification: Primary 47D03; 42B25; 47D09
SOME BASIC RESULTS FOR PROPER FREE G-MANIFOLDS, WHERE G IS A DISCRETE GROUP
Authors: Kankaanrinta Marja
Published: August 2008

Let $G$ be a countable discrete group and let $M$ be a proper free $C^r$ $G$-manifold and $N$ a $C^r$ $G$-manifold, where $1\leq r\leq\omega$. We prove that if $G$ acts properly and freely also on $N$ and if $\dim(N)\geq2\dim(M)$, then equivariant immersions form an open dense subset in the space $C^r_G(M,N)$ of all equivariant $C^r$ maps from $M$ to $N$. The space $C^r_G(M,N)$ is equipped with a topology, which coincides with the Whitney $C^r$ topology if $G$ is finite and is suited to studying equivariant maps. We also prove an equivariant version of Thom’s transversality theorem and show that $C^\omega_G(M,N)$ is dense in $C^r_G(M,N)$, for $1\leq r\leq\infty$.

AMS 2000 Mathematics subject classification: Primary 57S20
ON THE MAIN INVARIANT OF ELEMENTS ALGEBRAIC OVER A HENSELIAN VALUED FIELD
Authors: Aghigh Kamal , Khanduja Sudesh K.
Published: August 2008

Let $v$ be a henselian valuation of a field $K$ with value group $G$, let $\bar{v}$ be the (unique) extension of $v$ to a fixed algebraic closure $\bar{K}$ of $K$ and let $(\tilde{K},\tilde{v})$ be a completion of $(K,v)$. For $\alpha\in\bar{K}\setminus K$, let $M(\alpha,K)$ denote the set $\{\bar{v}(\alpha-\beta):\beta\in\bar{K},\ [K(\beta):K] \lt [K(\alpha):K]\}$. It is known that $M(\alpha,K)$ has an upper bound in $\bar{G}$ if and only if $[K(\alpha):K]=[\tilde{K}(\alpha):\tilde{K}]$, and that the supremum of $M(\alpha,K)$, which is denoted by $\delta_{K}(\alpha)$ (usually referred to as the main invariant of $\alpha$), satisfies a principle similar to the Krasner principle. Moreover, each complete discrete rank 1 valued field $(K,v)$ has the property that $\delta_{K}(\alpha)\in M(\alpha,K)$ for every $\alpha\in\bar{K}\setminus K$. In this paper the authors give a characterization of all those henselian valued fields $(K,v)$ which have the property mentioned above.

AMS 2000 Mathematics subject classification: Primary 12J10; 12J25; 13A18
A GENERALIZATION OF THE WIDDER–ARENDT THEOREM
Authors: Chojnacki Wojciech
Published: August 2008

We establish a generalization of the Widder–Arendt theorem from Laplace transform theory. Given a Banach space $E$, a non-negative Borel measure $\mea$ on the set $\Rplus$ of all non-negative numbers, and an element $\bnd$ of $\R\cup\{-\infty\}$ such that $\natres{-\coefl}$ is $\mea$-integrable for all $\coefl>\bnd$, where $\natres{-\coefl}$ is defined by $\natres{-\coefl}(t)=\exp(-\coefl t)$ for all $t\in\Rplus$, our generalization gives an intrinsic description of functions $\f\colon\Set\to E$ that can be represented as $\f(\coefl)=T(\natres{-\coefl})$ for some bounded linear operator $T\colon\Ma\to E$ and all $\coefl> \bnd$; here $\Ma$ denotes the Lebesgue space based on $\mea$. We use this result to characterize pseudo-resolvents with values in a Banach algebra, satisfying a growth condition of Hille–Yosida type.

AMS 2000 Mathematics subject classification: Primary 44A10; 47A10. Secondary 43A20; 46B22; 46G10; 46J25; 47D06
ALGEBRAIC CURVES, RIEMANN SURFACES AND KLEIN SURFACES WITH NO NON-TRIVIAL AUTOMORPHISMS OR SYMMETRIES
Authors: Turbek Peter
Published: August 2008

The explicit defining equations of a new family of curves whose members have a trivial automorphism group are given. Each member is defined for characteristic zero and all but a finite number of characteristics greater than zero. This family, in conjunction with a previously appearing family of the author’s, provides explicit examples of algebraic curves which possess only the trivial automorphism for each genus greater than three. The family is then used to construct Riemann surfaces without anticonformal automorphisms and Klein surfaces with no non-trivial automorphisms.

AMS 2000 Mathematics subject classification: Primary 14H37; 30F50; 30F99
CODIFYING TORT LAW: LESSONS FROM THE PROPOSALS FOR REFORM OF THE FRENCH CIVIL CODE
Authors: Giliker Paula
Published: August 2008

This article deals with a topic at the heart of modern comparative law: codification of private law on a national and European level. It offers a critical assessment of the recent French attempt to redraft the obligations provisions of its civil code, focusing on the revisions to the law of tort or delict. There has been little analysis of these provisions within or outside France. This article examines the key changes proposed and identifies the implications in terms of tort policy.
Detection of QTL for milk protein percentage in Italian Friesian cattle by AFLP markers and selective genotyping
Authors: Milanesi Elisabetta , Negrini Riccardo , Schiavini Fausta , Nicoloso Letizia , Mazza Raffaele , Canavesi Fabiola , Miglior Filippo , Valentini Alessio , Bagnato Alessandro , Ajmone-Marsan Paolo
Published: August 2008

We targeted quantitative trait loci (QTL) for milk protein percentage (P%) in two Italian Holstein granddaughter design families using selective genotyping in combination with high throughput amplified fragment length polymorphism (AFLP) markers. A total of 64 extreme high and low sires in respect to estimated breeding value (EBV) for P% (EBVP%) were genotyped with 25 AFLP primer combinations that revealed 305 and 291 polymorphisms in the two families. Association between markers and EBVP% was investigated by a linear model only on bands having paternal origin (105 and 96 AFLP bands in family D and S, respectively). Although no marker was significantly associated with the target trait after correction for multiple comparisons, 17 AFLP markers, significant without correction for multiple tests, were considered suggestive of the presence of a QTL. Eleven of these were successfully located on sixBos taurus(BTA) chromosomes by radiation hybrid or in-silico mapping. Ten of these mapped in the immediate neighbourhood (less than 10 cM) of already described QTL for P%. Suggestive association was verified in four regions by microsatellites analysis: one on BTA 10; one on BTA 28; and two on BTA 18. Microsatellites identified significant effects by single marker and interval mapping analyses on BTA 10 and BTA 28, while they were only suggestive of the presence of QTL on BTA 18. In summary, our results firstly indicate that AFLP markers may be used to seek QTL exploiting a selective genotyping approach in GDD, a wide used experimental design in cattle; secondly, propose two approaches for AFLP mapping, namely in-silico mapping exploiting most updated release from the bovine whole genome sequencing project, and physical mapping exploiting a panel of Bovine/Hamster Radiation Hybrids; and thirdly, provide new information on QTLs for an economic important trait in a never investigated Holstein cattle population. AFLP in combination with selective genotyping can be a useful strategy for QTL searching in minor livestock species, sometimes having large economic impact in marginal areas, where more informative markers are still poorly developed.
Effect of diet supplementation with sunflower oil on milk production, fatty acid profile and ruminal fermentation in lactating dairy ewes
Authors: Hervás Gonzalo , Luna Pilar , Mantecón Ángel R. , Castañares Natalia , de la Fuente Miguel Angel , Juárez Manuela , Frutos Pilar
Published: August 2008

The aim of this research was to enhance the nutritional quality of ewe milk fat by increasing potentially healthy fatty acids (FA) through diet supplementation with unprotected oil rich in linoleic acid, and without detrimental effects on animal performance. Twenty-four ewes were assigned to two high concentrate diets, control or supplemented with 6% sunflower oil (SO), for 4 weeks. No differences between treatments were found in milk production and dry matter intake. Although the SO diet increased milk fat percentage and tended to reduce milk protein concentration, it did not affect milk fat, protein or total solid yield. Most of the modifications in milk FA composition were addressed toward a potentially healthier profile: a decrease in C12:0 to C16:0 and a remarkable increase in the contents of cis-9 trans-11 C18:2 (from 0·94 to 3·60 g/100 g total FA) and trans-11 C18:1 (from 2·23 to 8·61 g/100 g total FA). Furthermore, the levels reached were maintained throughout the period monitored. However, the SO diet increased other trans C18:1 isomer percentages, too. The lack of differences between treatments in the in vitro ruminal fermentation parameters, studied with batch cultures of rumen microorganisms, would indicate no negative effects on ruminal fermentation.
Civil society, oil and conflict in the Niger Delta region of Nigeria: ramifications of civil society for a regional resource struggle
Authors: Ikelegbe Augustine
Published: August 2008

Civil society has been associated with challenges and popular struggles for state and democratic reforms. Though these may relate to the articulation of substantive ethnic, regional and communal demands, few studies have addressed the dynamics and ramifications of their engagement in struggles other than democratisation. This study focuses on the ramifications of the entrance of civil society into a regional resource agitation in the Niger Delta region of Nigeria. The study finds that civil society has flowered, taken over and escalated the struggle and constructed itself into a solid formation of regional resistance. Civil groups have reconstructed the agitation into a broad, participatory, highly mobilised and coordinated struggle and redirected it into a struggle for self-determination, equity and civil and environmental rights. The study denotes the roles that civil society can play in the sociopolitical process and reveals the dynamics of their encounters with the state and multinational corporations.
Texts, Raja Ismail and Violence: Siak and the Transformation of Malay Identity in the Eighteenth Century
Authors: Barnard Timothy P.
Published: August 2008

In the eighteenth century the descendants of a variety of groups, including Minangkabaus, formed a new Malay state known as Siak. Through an examination of a traditional text, Hikayat Siak, a better understanding of how Malay identity expanded beyond the polity of Johor–Melaka, and was understood, is provided. A key factor in this transformation is how a prince, Raja Ismail, developed a Malay identity through raiding and violence.
A Literary Mycelium: Some Prolegomena for a Project on Indonesian Literatures in Malay
Authors: Derks Will
Published: August 2008

This article consists of two parts. First, some of the presuppositions that have moulded the dominant view of and approach to Indonesian literature are examined and contrasted with certain facts in the literary life of modern Indonesia. This results in the proposing of a ‘project’ in which this view and approach will have changed fundamentally. The biological species of the mycelium is used as a metaphor to reflect this change. The second part of the article is a case study that suggests how in a concrete way the Indonesian mycelium of literatures in Malay might be approached.
The Makassar Malays: Adaptation and Identity, c. 1660-1790
Authors: Sutherland Heather
Published: August 2008

Extensive trade networks and Islam shaped Malay identity. The Dutch conquest of Makassar (1666-69) compelled the Malays there to redefine themselves, mastering new trade routes, political arenas and social alliances. During the eighteenth century they both evaded and exploited ethnic classification, as their enforced focus on regional commerce and integration into port society encouraged localisation.
Variation and immunity to intestinal worms
Authors: WAKELIN D. , FARIAS S. E. , BRADLEY J. E.
Published: August 2008

Genetically determined variation in host capacity to express resistance to a given parasite plays a major role in determining the outcome of infection. It can be assumed that the same is true of variation in parasites, but very much less is known of its influence on the host–parasite relationship. Phenotypic and genotypic variation within species of intestinal worms is now well documented, detailed studies having been made of parasites such asAscarisin humans and trichostrongyles in domestic animals. However, the extent to which this variation affects the course of infection or the host immune response in these hosts is limited. Of the nematodes used as experimental models in laboratory rodents, detailed data on phenotypic or genotypic variation are limited toStrongyloidesandTrichinella. Parasite variation is known to be subject to host-mediated selection, the emergence of anthelmintic resistance being a good example. Repeated passage has been used to select lines of parasite that survive in abnormal hosts or which show adaptation to host immunity. Experimental studies withTrichinellagenotypes in mice have demonstrated the extent to which parasite variation influences the nature and degree of the host's immune and inflammatory responses, the complex interplay between immunogenicity and pathogenicity influencing both partners in the relationship. Recent studies with isolates ofTrichuris murishave shown how parasite variation influences the capacity of mice to express the T helper cell responses necessary for resistance. Molecular differences betweenT. murisisolates have been shown in their excreted/secreted products as well as at the level of their DNA. Knowledge of the functional consequences of parasite variation will add to our understanding of host-parasite evolution as well as providing a rational basis for predicting the outcome of controls strategies that rest on the improvement of host resistance through vaccination or selective breeding.
SSCP-based identification of members within the Pseudoterranova decipiens complex (Nematoda: Ascaridoidea: Anisakidae) using genetic markers in the internal transcribed spacers of ribosomal DNA
Authors: ZHU X. Q. , D'AMELIO S. , PALM H. W. , PAGGI L. , GEORGE-NASCIMENTO M. , GASSER R. B.
Published: August 2008

The anisakid nematodes morphologically corresponding with Pseudoterranova decipiens sensu lato (s.l.) (Krabbe, 1878) from different seal or sea lion hosts and geographical origins, previously identified as Pseudoterranova krabbei, P. decipiens (s.s.), P. bulbosa, P. azarasi and P. cattani by multilocus enzyme electrophoresis, were characterized using a DNA approach. Also a population of P. decipiens (s.l.) from Chaenocephalus aceratus, the blackfin icefish, from Antarctica and another from Osmerus eperlanus, the European smelt, from Germany were included in the study. The first (ITS-1) and second (ITS-2) internal transcribed spacers (ITS) of ribosomal DNA (rDNA) were amplified by PCR from individual nematodes and analysed by single-strand conformation polymorphism (SSCP), followed by selective sequencing. While no variation in single-stranded ITS-1 and ITS-2 profiles was detected among samples representing each of the species or populations (with the exception of slight microheterogeneity), SSCP analysis of the ITS-2 amplicons allowed the unequivocal differentiation of all of the 5 sibling species of P. decipiens (s.l.) examined, which was supported by sequence differences in ITS rDNA. Samples representing the P. decipiens (s.l.) population from O. eperlanus had the same SSCP profile as those of P. decipiens (s.s.), which was supported by a lack of nucleotide difference in the ITS between them, suggesting that the former represented P. decipiens (s.s.). Based on SSCP results and ITS sequence data, P. decipiens (s.l.) from C. aceratus was genetically most distinct with respect to all other members of Pseudoterranova examined, which indicated that it may represent P. decipiens E (based on geographical origin) or a distinct species. These findings and the molecular approach taken should have important implications for studying the life-cycles, transmission patterns, epidemiology and population genetics of these anisakid nematodes, and the diagnosis of their infections.
Selection pressure towards monoxeny in Camallanus cotti (Nematoda, Camallanidae) facing an intermediate host bottleneck situation
Authors: LEVSEN A. , JAKOBSEN P. J.
Published: August 2008

This paper describes the ability of the Asian fish nematode Camallanuscotti to carry out both heteroxeny, i.e. an indirect life-cycle using copepods as intermediate host, and monoxeny, i.e. direct infection and development in the definitive fish host. C. cotti occurs naturally in various freshwater teleosts in Asia. During the past decades it has been disseminated into closed or semi-closed aquaculture systems and aquaria around the world, mainly due to the ornamental fish trade. Under such conditions the species may frequently face a bottleneck situation with regard to the availability of copepods. It is known that C. cotti may reproduce and persist in copepod-free aquaria for several months. In order to investigate whether C. cotti has selected towards monoxeny in water systems lacking copepods, in contrast to the opposite selection pressure when copepods are present, 2 separate infection trials were run. It was shown that the parasite can infect the fish host both indirectly via copepods, and directly. However, C. cotti has significantly higher fitness, expressed as survival to maturity, when transmitted indirectly compared to the direct transmission mode. We suggest that the ability of aquarium populations of C. cotti to carry out a direct life-cycle is favoured by selection in order to avoid extinction whenever copepods are absent. It still remains unknown, however, whether the parasite shows the same characteristics in the wild.
The time-course of the response to the FMRFamide-related peptide PF4 in Ascaris suum muscle cells indicates direct gating of a chloride ion-channel
Authors: PURCELL J. , ROBERTSON A. P. , THOMPSON D. P. , MARTIN R. J.
Published: August 2008

We investigated the effects of PF4 on Ascaris suum somatic muscle cells using a 2 electrode current-clamp technique. PF4 is a FaRP (FMRFamide-related peptide), originally isolated from the free-living nematode Panagrellus redivivus. PF4 caused hyperpolarization and an increase in chloride ion conductance when it was applied to the muscle cells of the Ascaris body wall. The delay between the application of the peptide and the appearance of the response was measured and compared with that of gamma-amino butyric acid (GABA), a compound that directly gates ion channels, and with PF1, a FaRP that acts via an intracellular signal transduction mechanism. The PF4 and GABA delay times were not significantly different; they were 1·51±0·11 sec and 1·22±0·10 sec respectively. The delay following application of PF1, 3·75±0·51 sec, was significantly longer. The rapid response to PF4 is consistent with direct gating of a chloride ion channel, which has not been described elsewhere in the literature.
Comparison of the structures of natural and re-established populations of Ascaris in humans in a rural community of Jiangxi, China
Authors: PENG W. , ZHOU X. , CUI X.
Published: August 2008

To compare the structures of natural and re-established populations of Ascaris in humans, universal (mass) chemotherapy was carried out at the beginning and the end of the study year using pyrantel pamoate. Worms expelled within 48 h of treatment were collected, their sex determined, and measurements made of length, width and weight. Length was used as the criterion for estimating the developmental stage of the worms. In comparison with the natural population, the re-established population displayed similar sex ratio as well as distribution patterns among individuals and age groups of the host. However, the mean worm burden of the re-established population was significantly decreased, with a reduction of burdens in children aged 5–9 years. Also, the re-established population showed significant changes in population structure and worm measurements in that it comprised more immature and less fertile males, less fertile and more senile females, smaller and lighter males, larger (but not heavier) females than the natural population. The results suggested that the re-established Ascaris population did not restore to its original status in relation to mean density, composition and fecundity. Therefore, universal treatment once a year should decrease the transmission of Ascaris in humans. Combined with previous results for the same study sites, the present findings also indicated that caution is warranted to avoid misleading conclusions when using prevalence and faecal egg counts as parameters for evaluating the success of control programmes.
Spatial and temporal aspects of urban transmission of Echinococcus multilocularis
Authors: STIEGER C. , HEGGLIN D. , SCHWARZENBACH G. , MATHIS A. , DEPLAZES P.
Published: August 2008

High prevalences of Echinococcus multilocularis have been reported from foxes of the city of Zurich, Switzerland. In order to characterize transmission in urban areas, a coproantigen ELISA was evaluated for diagnosing the infection in fox faecal samples collected in the environment. In addition, trapped rodents were investigated for the presence of metacestodes. Faecal samples could reliably be classified as being of fox origin by assessing physical properties as shown by the different parasite spectra of putative fox and dog faecal specimens. From the total of 604 tested putative fox faecal samples 156 (25·8%) were positive in the ELISA with a distinct increase in the proportion of positive samples from the urban to the periurban zone. Furthermore, samples collected in the border zone had significantly more coproantigen-positive results during winter. Prevalence of E. multilocularis in rodents was 9·1% (81/889) for Arvicola terrestris (with 3·5% of the animals harbouring between 14 and 244400 protoscoleces) and 2·4% (2/83) for Clethrionomys glareolus. E. multilocularis-infected A. terrestris were found in 9 of 10 trapping sites in the border zone. The high infection pressure in the periphery of urban areas might pose a risk for infection with E. multilocularis for both domestic carnivores as well as for urban inhabitants. Interventions into the cycle aiming at reducing the infection pressure should therefore focus on these areas.
The epidemiological consequences of optimisation of the individual host immune response
Authors: MEDLEY G. F.
Published: August 2008

We present a simple unscaled, quantitative framework that addresses the optimum use of resources throughout a host's lifetime based on continuous exposure to parasites (rather than evolutionary, genetically explicit trade-offs). The principal assumptions are that a host's investment of resources in growth increases its survival and reproduction, and that increasing parasite burden reduces survival. The host reproductive value is maximised for a given combination of rates of parasite exposure, host resource acquisition and pathogenicity, which results in an optimum parasite burden (for the host). Generally, results indicate that the optimum resource allocation is to tolerate some parasite infection. The lower the resource acquisition, the lower the proportion of resources that should be devoted to immunity, i.e. the higher the optimum parasite burden. Increases in pathogenicity result in reduced optimum parasite burdens, whereas increases in exposure result in increasing optimum parasite burdens. Simultaneous variation in resource acquisition, pathogenicity and exposure within a community of hosts results in overdispersed parasite burdens, with the degree of heterogeneity decreasing as mean burden increases. The relationships between host condition and parasite burden are complicated, and could potentially confound data analysis. Finally, the value of this approach for explaining epidemiological patterns, immunological processes and the possibilities for further work are discussed.