bluuebunny/crossref_metadata_2025 huggingface dataset:
Composite high resolution localized relaxation scheme based on upwinding for hyperbolic conservation laws
Authors: Dubey Ritesh Kumar , Kadalbajoo M. K.
Published: November 2008

In this work we present an upwind‐based high resolution scheme using flux limiters. Based on the direction of flow we choose the smoothness parameter in such a way that it leads to a truly upwind scheme without losing total variation diminishing (TVD) property for hyperbolic linear systems where characteristic values can be of either sign. Here we present and justify the choice of smoothness parameters. The numerical flux function of a high resolution scheme is constructed using wave speed splitting so that it results into a scheme that truly respects the physical hyperbolicity property. Bounds are given for limiter functions to satisfy TVD property. The proposed scheme is extended for non‐linear problems by using the framework of relaxation system that converts a non‐linear conservation law into a system of linear convection equations with a non‐linear source term. The characteristic speed of relaxation system is chosen locally on three point stencil of grid. This obtained relaxation system is solved using composite scheme technique, i.e. using a combination of proposed scheme with the conservative non‐standard finite difference scheme. Presented numerical results show higher resolution near discontinuity without introducing spurious oscillations. Copyright © 2008 John Wiley & Sons, Ltd.
Triterpenoids from Eucalyptus camaldulensisDehnh. Tissue Cultures
Authors: Tsiri Dimitroula , Aligiannis Nektarios , Graikou Konstantia , Spyropoulos Caroline , Chinou Ioanna
Published: November 2008

A chemical study on tissue cultures from leaves and flowers of E. camaldulensis Dehnh. afforded the new natural product (2α,3β)‐2,3,23‐trihydroxy‐13,28‐epoxyurs‐11‐en‐28‐one (dryobalanolide) together with the known pentacyclic triterpenoids: betulinic acid, oleanolic acid, ursolic acid, (2α,3β)‐2,3,23‐trihydroxyolean‐12‐en‐28‐oic acid (arjunolic acid), (2α,3β)‐2,3,23‐trihydroxyurs‐12‐en‐28‐oic acid (asiatic acid), (2α)‐2‐hydroxyursolic acid, (2α)‐2‐hydroxyoleanolic acid (maslinic acid), as well as β‐sitosterol. The extracts and the isolated compounds were evaluated against eleven human pathogenic microorganisms, exhibiting a very interesting antibacterial spectrum of activities.
Indole Alkaloids from the Leaves of Anthocephalus chinensis
Authors: Zhou Hua , He Hong‐Ping , Kong Ning‐Chuan , Wang Tie‐Jun , Hao Xiao‐Jiang
Published: November 2008

Anthocephalusine A (1) and 3β‐isodihydrocadambine 4‐oxide (2) were isolated from the leaves of Anthocephalus chinensis (Rubiaceae), together with five known compounds. The structures were established by spectroscopic methods including 2D‐NMR analyses.
Oligonucleotide Analogues with Integrated Bases and Backbones. Part 19.
Authors: Bogliotti Nicolas , Ritter Anne , Hebbe Séverine , Vasella Andrea
Published: November 2008

The A*[s]U(*) dinucleosides 1 and 2 form thermoreversible gels in organic solvents. The basis of the gelation is the formation of linear aggregates by base pairing following desolvation of the nucleobases. This is evidenced by the absence of gel formation by the C(6)‐deaminated analogue 3 of 1, the correlation of gelation with the anti‐conformation, as preferred for 1, and the temperature‐, concentration‐, and time‐dependent CD spectra. The gels were also characterized by the minimum gelation concentration, the gel–sol transition (melting) temperature, and rheological properties.
MiRNA expression in urothelial carcinomas: Important roles of miR‐10a, miR‐222, miR‐125b, miR‐7 and miR‐452 for tumor stage and metastasis, and frequent homozygous losses of miR‐31
Authors: Veerla Srinivas , Lindgren David , Kvist Anders , Frigyesi Attila , Staaf Johan , Persson Helena , Liedberg Fredrik , Chebil Gunilla , Gudjonsson Sigurdur , Borg Åke , Månsson Wiking , Rovira Carlos , Höglund Mattias
Published: November 2008

We analyzed 34 cases of urothelial carcinomas by miRNA, mRNA and genomic profiling. Unsupervised hierarchical clustering using expression information for 300 miRNAs produced 3 major clusters of tumors corresponding to Ta, T1 and T2‐T3 tumors, respectively. A subsequent SAM analysis identified 51 miRNAs that discriminated the 3 pathological subtypes. A score based on the expression levels of the 51 miRNAs, identified muscle invasive tumors with high precision and sensitivity. MiRNAs showing high expression in muscle invasive tumors included miR‐222 and miR‐125b and in Ta tumors miR‐10a. A miRNA signature for FGFR3 mutated cases was also identified with miR‐7 as an important member. MiR‐31, located in 9p21, was found to be homozygously deleted in 3 cases and miR‐452 and miR‐452* were shown to be over expressed in node positive tumors. In addition, these latter miRNAs were shown to be excellent prognostic markers for death by disease as outcome. The presented data shows that pathological subtypes of urothelial carcinoma show distinct miRNA gene expression signatures. © 2008 Wiley‐Liss, Inc.
In vitro and in vivo study of phloretin‐induced apoptosis in human liver cancer cells involving inhibition of type II glucose transporter
Authors: Wu Chih‐Hsiung , Ho Yuan‐Soon , Tsai Chia‐Yi , Wang Ying‐Jan , Tseng How , Wei Po‐Li , Lee Chia‐Hwa , Liu Ren‐Shyan , Lin Shyr‐Yi
Published: November 2008

Phloretin (Ph), a natural product found in apples and pears with glucose transporter (GLUT) inhibitory activity, exerts antitumor effects. However, little is known about its effects on human liver cancer. The purpose of this study is to test the cytotoxic effects of Ph on HepG2 cells and to identify the underlying molecular pathways. Human hepatocellular carcinoma specimens and HepG2 show a high level of GLUT2 transporter activity in the cell membrane. Real‐time PCR and MTT assays demonstrate that Ph‐induced cytotoxicity correlates with the expression of GLUT2. Flow cytometry and DNA fragmentation studies show that 200 μM Ph induces apoptosis in HepG2, which was reversed by glucose pretreatment. GLUT2 siRNA knockdown induced HepG2 apoptosis, which was not reversed by glucose. Western blot analysis demonstrates that both intrinsic and extrinsic apoptotic pathways in addition to Akt and Bcl‐2 family signaling pathways are involved in Ph‐induced cell death in HepG2 cells. Furthermore, using flow cytometry analysis, a mitochondrial membrane potential assay and Western blot analysis, we show that cytochalasin B, a glucose transport inhibitor, enhances the Ph‐induced apoptotic effect on HepG2 cells, which was reversed by pretreatment with glucose. Furthermore, we found significant antitumor effects in vivo by administering Ph at 10 mg/kg intraperitoneally to severe combined immune deficiency mice carrying a HepG2 xenograft. A microPET study in the HepG2 tumor‐bearing mice showed a 10‐fold decrease in 18F‐FDG uptake in Ph‐treated tumors compared to controls. Taken together, these results suggest that Ph‐induced apoptosis in HepG2 cells involves inhibition of GLUT2 glucose transport mechanisms. © 2008 Wiley‐Liss, Inc.
Comprehensive gene expression profiling in lungs of mice infected with Mycobacterium tuberculosis following DNAhsp65 immunotherapy
Authors: Zárate‐ Bladés Carlos Rodrigo , Bonato Vânia Luiza Deperon , da Silveira Eduardo Lani Volpe , e Paula Marina Oliveira , Junta Cristina Moraes , Sandrin‐Garcia Paula , Fachin Ana Lúcia , Mello Stephano Spanó , Cardoso Renato Sousa , de Sá Galetti Fábio Cícero , Coelho‐Castelo Arlete Aparecida Martins , Ramos Simone Gusmão , Donadi Eduardo Antonio , Sakamoto‐Hojo Elza Tiemi , da Silva Passos Geraldo Aleixo , Silva Celio Lopes
Published: November 2008

Background

The continued increase in tuberculosis (TB) rates and the appearance of extremely resistant Mycobacterium tuberculosis strains (XDR‐TB) worldwide are some of the great problems of public health. In this context, DNA immunotherapy has been proposed as an effective alternative that could circumvent the limitations of conventional drugs. Nonetheless, the molecular events underlying these therapeutic effects are poorly understood.

Methods

We characterized the transcriptional signature of lungs from mice infected with M. tuberculosis and treated with heat shock protein 65 as a genetic vaccine (DNAhsp65) combining microarray and real‐time polymerase chain reaction analysis. The gene expression data were correlated with the histopathological analysis of lungs.

Results

The differential modulation of a high number of genes allowed us to distinguish DNAhsp65‐treated from nontreated animals (saline and vector‐injected mice). Functional analysis of this group of genes suggests that DNAhsp65 therapy could not only boost the T helper (Th)1 immune response, but also could inhibit Th2 cytokines and regulate the intensity of inflammation through fine tuning of gene expression of various genes, including those of interleukin‐17, lymphotoxin A, tumour necrosis factor‐α, interleukin‐6, transforming growth factor‐β, inducible nitric oxide synthase and Foxp3. In addition, a large number of genes and expressed sequence tags previously unrelated to DNA‐therapy were identified. All these findings were well correlated with the histopathological lesions presented in the lungs.

Conclusions

The effects of DNA therapy are reflected in gene expression modulation; therefore, the genes identified as differentially expressed could be considered as transcriptional biomarkers of DNAhsp65 immunotherapy against TB. The data have important implications for achieving a better understanding of gene‐based therapies. Copyright © 2008 John Wiley & Sons, Ltd.
Halohydrination of epoxy resins using sodium halides as cationizing agents in MALDI‐MS and DIOS‐MS
Authors: Watanabe Takehiro , Kawasaki Hideya , Kimoto Takashi , Arakawa Ryuichi
Published: November 2008

Halohydrination of epoxy resins using sodium halides as cationizing agents in matrix‐assisted laser desorption/ionization (MALDI) and desorption ionization on porous silicon mass spectrometry (DIOS‐MS) were investigated. Different mass spectra were observed when NaClO4 and NaI were used as the cationizing agents at the highest concentration of 10.0 mM, which is much higher than that normally used in MALDI‐MS. MALDI mass spectra of epoxy resins using NaI revealed iodohydrination to occur as epoxy functions of the polymers. The halohydrination also occurred using NaBr, but not NaCl, due to the differences in their nucleophilicities. On the basis of the results of experiments using deuterated CD3OD as the solvent, the hydrogen atom source was probably ambient water or residual solvent, rather than being derived from matrices. Halohydrination also occurred with DIOS‐MS in which no organic matrix was used; in addition, reduction of epoxy functions was observed with DIOS. NaI is a useful cationizing agent for changing the chemical form of epoxy resins due to iodohydrination and, thus, for identifying the presence of epoxy functions. Copyright © 2008 John Wiley & Sons, Ltd.
Recent advances in linear and nonlinear Raman spectroscopy II
Authors: Kiefer W.
Published: November 2008

Following the first review on recent advances in linear and nonlinear Raman spectroscopy, the present review summarizes papers mainly published in the Journal of Raman Spectroscopy during 2007. This serves to give a fast overview of recent advances in this research field as well as to provide readers of this journal a quick introduction to the various subfields of Raman spectroscopy. It also reflects the current research interests of the Raman community. Similar reviews of highly active areas of Raman spectroscopy will appear in future issues of this journal. Copyright © 2008 John Wiley & Sons, Ltd.
The influence of postharvest processing and storage of foodstuffs on the bioavailability of flavonoids and phenolic acids
Authors: Cermak Rainer , Durazzo Alessandra , Maiani Giuseppe , Böhm Volker , Kammerer Dietmar R. , Carle Reinhold , Wiczkowski Wieslaw , Piskula Mariusz K. , Galensa Rudolf
Published: November 2008

Postharvest processing and storage not only influence the content and composition of flavonoids and phenolic acids in foodstuffs, thereby altering the amount of potentially bioavailable bioactive compounds, but can also modify their chemical form. Moreover, due to the intensive metabolism during absorption, the metabolites circulating in blood differ from the parent compounds found in food. Thus, it is difficult to predict potential in vivo effects of phenolic compounds merely by their contents in foodstuffs. Their specific bioavailability needs to be determined. This review considers studies regarding the bioavailability of flavonoids and phenolic acids from foodstuffs that meet the following criteria: providing actual concentrations of flavonoids and phenolic acids in blood plasma, body tissues, or urine, comparing differently stored or processed foods (excluding studies that use supplements or pure substances), and considering the high interindividual variability by repeated measurements in the same individuals. Only a few studies meet all of these criteria. In conclusion, processing and storage of food can have either positive or negative effects on the bioavailability of flavonoids and phenolic acids because these treatments may not only change the content, but also the chemical form of these compounds.
A thermodynamic approach to the conformational preferences of the 180–195 segment derived from the human prion protein α2‐helix
Authors: Ronga Luisa , Palladino Pasquale , Ragone Raffaele , Benedetti Ettore , Rossi Filomena
Published: November 2008

On consideration that intrinsic structural weakness could affect the segment spanning the α2‐helical residues 173–195 of the PrP, we have investigated the conformational stabilities of some synthetic Ala‐scanned analogs of the peptide derived from the 180–195 C‐terminal sequence, using a novel approach whose theoretical basis originates from protein thermodynamics. Even though a quantitative comparison among peptides could not be assessed to rank them according to the effect caused by single amino acid substitution, as a general trend, all peptides invariably showed an appreciable preference for an α‐type organization, consistently with the fact that the wild‐type sequence is organized as an α‐helix in the native protein. Moreover, the substitution of whatever single amino acid in the wild‐type sequence reduced the gap between the α‐ and the β‐propensity, invariably enhancing the latter, but in any case this gap was larger than that evaluated for the full‐length α2‐helix‐derived peptide. It appears that the low β‐conformation propensity of the 180–195 region depends on the simultaneous presence of all of the Ala‐scanned residues, indirectly confirming that the N‐terminal 173–179 segment could play a major role in determining the chameleon conformational behavior of the entire 173–195 region in the PrP. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd.
Nonparametric methods for measurements below detection limit
Authors: Zhang Donghui , Fan Chunpeng , Zhang Juan , Zhang Cun‐Hui
Published: November 2008

Analytical data are often subject to left‐censoring when the actual values to be quantified fall below the limit of detection. The primary interest of this paper is statistical inference for the two‐sample problem. Most of the current publications are centered around naive approaches or the parametric Tobit model approach. These methods may not be suitable for data with high censoring rates and relatively small sample sizes. In this paper, we establish the theoretical equivalence of three nonparametric methods: the Wilcoxon rank sum, the Gehan, and the Peto‐Peto tests, under fixed left‐censoring and other mild conditions. We then develop a nonparametric point and interval estimation procedure for the location shift model. A large set of simulations compares 14 methods including naive, parametric, and nonparametric methods. The results clearly favor the nonparametric methods for a range of sample sizes and censoring rates. Simulations also demonstrate satisfactory point and interval estimation results. Finally, a real data example is given followed by discussion. Copyright © 2008 John Wiley & Sons, Ltd.
Exact and approximate unconditional confidence intervals for proportion difference in the presence of incomplete data
Authors: Tang Man‐Lai , Ling Man‐Ho , Tian Guo‐Liang
Published: November 2008

Confidence interval (CI) construction with respect to proportion/rate difference for paired binary data has become a standard procedure in many clinical trials and medical studies. When the sample size is small and incomplete data are present, asymptotic CIs may be dubious and exact CIs are not yet available. In this article, we propose exact and approximate unconditional test‐based methods for constructing CI for proportion/rate difference in the presence of incomplete paired binary data. Approaches based on one‐ and two‐sided Wald's tests will be considered. Unlike asymptotic CI estimators, exact unconditional CI estimators always guarantee their coverage probabilities at or above the pre‐specified confidence level. Our empirical studies further show that (i) approximate unconditional CI estimators usually yield shorter expected confidence width (ECW) with their coverage probabilities being well controlled around the pre‐specified confidence level; and (ii) the ECWs of the unconditional two‐sided‐test‐based CI estimators are generally narrower than those of the unconditional one‐sided‐test‐based CI estimators. Moreover, ECWs of asymptotic CIs may not necessarily be narrower than those of two‐sided‐based exact unconditional CIs. Two real examples will be used to illustrate our methodologies. Copyright © 2008 John Wiley & Sons, Ltd.
The impact of requirements changes on specifications and state machines
Authors: Lin L. , Prowell S. J. , Poore J. H.
Published: November 2008

Requirements change both during and after a phase of development for a variety of reasons, including error correction and feature changes. Requirements change management is one of the most complex and difficult problems to deal with in requirements elicitation and tracking. It is generally not understood how a specific change propagates through the specification and into the code. In this paper we capture requirements changes as series of atomic changes in specifications. Using a rigorous specification method called sequence‐based specification, we propose a set of algorithms for managing all possible atomic requirements changes. The algorithms have been formulated within an axiom system for sequence‐based specification and proven for correctness. They have also been implemented in a prototype tool with which users are able to push requirements changes through to changes in specifications, maintain old specifications over time and evolve them into new specifications with the least amount of human interaction and rework. The approach of utilizing state machines to model and manage requirements changes guarantees strong evidence about the correctness and completeness of the proposed theory that will lead to more reliable software in the presence of change, especially with embedded systems and safety‐critical systems. The solution described is general enough for adoption by software and system developers, and well suited for incremental development. Copyright © 2008 John Wiley & Sons, Ltd.
Pyrimidone derivative inhibits simian immunodeficiency virus‐induced apoptosis of CEM x174 cells
Authors: Gao Libo , Fu Shigan , Li Hui , Wang Xiaowei , Liu Junyi , Liu Han , Guo Liyuan , Liu Xinhua , Li Mengsen , McNutt Michael A. , Li Gang
Published: November 2008

The biochemical effects of 2‐(ethoxymethylthio)‐9‐phenyl‐cyclohepta[d]pyrimidone (EPCP), a novel non‐nucleoside reverse transcriptase inhibitor, have been investigated. Treatment with EPCP (EC50 of 0.88 nM in CEM x174 cells) significantly inhibited the activity of SIV reverse transcriptase and elevated the percentage of viable cells in an SIV‐infected sample in a dose‐dependent manner. The percentage of cells accumulated in G1 phase increased significantly from 34.5 to 62.4%, with a concomitant reduction in S‐phase from 50.7% in the control to 22.6% in the infected group. This cell cycle profile was restored by treatment with EPCP. SIV upregulated the levels of the caspase‐3, p53 and bax proteins, and downregulated the level of bcl‐2 in infected cells. The apoptotic effect of SIV was also blocked by treatment with EPCP. The pharmacological effects of EPCP paralleled those of AZT, suggesting the possibility that EPCP might be a novel antiviral agent for SIV.
A novel association of mGluR1a with the PDZ scaffold protein CAL modulates receptor activity
Authors: Zhang Jiuqin , Cheng Shan , Xiong Ying , Ma Yanmei , Luo Dali , Jeromin Andreas , Zhang Hong , He Junqi
Published: November 2008

MINT‐6797987, MINT‐6798009:

NHERF‐2 (uniprotkb:Q15599) binds (MI:0407) to mGluR1a (uniprotkb:Q9R0W0) by protein array (MI:0089)

MINT‐6798026, MINT‐6798048, MINT‐6798066:

mGluR1a (uniprotkb:Q9R0W0) physically interacts (MI:0218) with CAL (uniprotkb:Q9HD26) by pull down (MI:0096)

MINT‐6797953, MINT‐6797970:

NHERF‐1 (uniprotkb:O14745) binds (MI:0407) to mGluR1a (uniprotkb:Q9R0W0) by protein array (MI:0089)

MINT‐6797935:

CAL (uniprotkb:Q9HD26) binds (MI:0407) to mGluR1a (uniprotkb:Q9R0W0) by protein array (MI:0089)

MINT‐6798084:

CAL (uniprotkb:Q9HD26) binds (MI:0407) to mGluR1a (uniprotkb:Q9R0W0) by filter binding (MI:0049)

MINT‐6798134:

mGluR1a (uniprotkb:Q9R0W0) physically interacts (MI:0218) with CAL (uniprotkb:Q9HD26) by anti tag coimmunoprecipitation (MI:0007)

MINT‐6798158:

CAL (uniprotkb:B4F775) physically interacts (MI:0218) with mGluR1a (uniprotkb:Q9R0W0) by anti bait coimmunoprecipitation (MI:0006)

MINT‐6798233:

CAL (uniprotkb:Q9HD26) colocalizes (MI:0403) with mGluR1a (uniprotkb:Q9R0W0) by fluorescence microscopy (MI:0416)
The role of microtubule‐associated protein 1S in SOCS3 regulation of IL‐6 signaling
Authors: Zou Tingting , Ouyang Lu , Chen Lu , Dong Wei , Qiao Hong , Liu Yingle , Qi Yipeng
Published: November 2008

MINT‐6796998:

SOCS3 (uniprotkb:O35718) physically interacts (MI:0218) with MAP1S (uniprotkb:Q66K74) by anti bait coimmunoprecipitation (MI:0006)

MINT‐6796957:

SOCS3 (uniprotkb:O14543) physically interacts (MI:0218) with MAP1S (uniprotkb:Q66K74) by pull down (MI:0096)

MINT‐6796909, MINT‐6796875, MINT‐6796894, MINT‐6796936:

SOCS3 (uniprotkb:O14543) physically interacts (MI:0218) with MAP1S (uniprotkb:Q66K74) by two hybrid (MI:0018)

MINT‐6797017:

MAP1S (uniprotkb:Q8C052) physically interacts (MI:0218) with SOCS3 (uniprotkb:O35718) by anti bait coimmunoprecipitation (MI:0006)

MINT‐6796979:

MAP1S (uniprotkb:Q66K74) and SOCS3 (uniprotkb:O14543) colocalize (MI:0403) by fluorescence microscopy (MI:0416)
A Cross-National Comparison of Welfare Lobby Groups: The British Child Poverty Action Group (CPAG) and the Australian Council of Social Service (ACOSS)
Authors: Mendes Philip
Published: November 2008

Theories of globalisation suggest that national lobby groups continue to exert significant impact on social policy outcomes. This paper compares two prominent national welfare lobby groups, the British Child Poverty Action Group (CPAG), and the Australian Council of Social Service (ACOSS). Attention is drawn to their similarities and differences in a number of areas including their origins, major aims and objectives, representation, ideology, funding, lobbying strategies and targets, and political influence and effectiveness. Some conclusions are drawn from this comparison about the complexity of the relationship between globalisation and national welfare states.
Wage Reforms, Fiscal Policies and their Impact on Doctors’ Clinical Behaviour in China's Public Health Sector
Authors: Yang Jingqing
Published: November 2008

A recent report evaluating the medical reform carried out over the past two decades describes the outcome of the reform as a failure. It contends that the medical reform failed to contain the costs of health care, making medical services less and less accessible to the people, especially the poor. This paper explores how the wage reforms in Chinas public health sector since 1978 have contributed to the failure, with a focus on three new wage schemes: the bonus scheme, the “commission” scheme and the contract responsibility system. The paper argues that the decline of government investment in health care, the government's continuous control of medical services pricing and the pressure for the public medical facilities and professionals to increase their income have not only driven the health costs irrationally high, but also forced the facilities and doctors to resort to illegal means for this income.
Effect of αs1-casein (CSN1S1) genotype on milk CSN1S1 content in Malagueña and Murciano-Granadina goats
Authors: Caravaca Francisco , Amills Marcel , Jordana Jordi , Angiolillo Antonella , Agüera Pastora , Aranda Cristina , Menéndez-Buxadera Alberto , Sánchez Alfonso , Carrizosa Juan , Urrutia Baltasar , Sànchez Armand , Serradilla Juan Manuel
Published: November 2008

There is substantial evidence showing that the polymorphism of the goat αs1-casein (CSN1S1) gene has a major effect on milk protein, casein and fat content as well as on cheese yield. However, its influence on the synthesis rate of CSN1S1 has been less studied, with measurements only available in French breeds. In this article, we have measured milk CSN1S1 content in 89 Malagueña and 138 Murciano-Granadina goats with 305 and 460 phenotypic registers, respectively. In the Malagueña breed, average values of CSN1S1 content estimated forBB,BF,EEandFFgenotypes were 6·94±0·38, 5·36±0·22, 4·58±0·13 and 3·98±0·27 g/l, respectively, being all significantly different (P<0·05). Conversely, in the Murciano-Granadina breed only theBBgenotype (8·50±0·60 g/l) was significantly associated with increased levels of CSN1S1 (P<0·05), whereasBF(6·56±0·82 g/l),EE(6·39±0·60 g/l) andEF(6·91±0·76 g/l) genotypes displayed non-significant differences when compared with each other. Our results highlight the existence of breed-specific genetic and/or environmental factors modulating the impact of theCSN1S1gene polymorphism on the synthesis rate of the corresponding protein.
Solidification of free liquid films
Authors: ANDERSON ANTHONY M. , DAVIS STEPHEN H.
Published: November 2008

We examine steady longitudinal freezing of a two-dimensional single-component free liquid film. In the liquid, there are thermocapillary and volume-change flows as a result of temperature gradients along the film and density change upon solidification. We examine these flows, heat transfer, and interfacial shapes using an asymptotic analysis which is valid for thin films with small aspect ratios. These solutions depend sensitively on contact conditions at the tri-junctions. In particular, when the sum of the angles formed in the solid and liquid phases falls below a critical value, the existence of steady solutions is lost and the liquid film cannot be continuous, suggesting breakage of the film owing to freezing. The solutions are relevant to the freezing of foams of metals or ceramics, materials unaffected by surface active agents.
Neuropsychologische Befunde zu Merk- und Lernstörungen bei Kindern anhand des BASIC-MLT
Authors: Lepach Anja C. , Gienger Claudia , Petermann Franz
Published: November 2008

Zusammenfassung: Fragestellung: Unerkannt wirken sich Merk- und Lernstörungen bei Kindern nachhaltig auf die gesamte Entwicklung aus und schränken Therapieerfolge ein. Die differenzierte Erfassung von Art und Ausmaß der Merk- und Lernstörung ist wesentlich für gezielte Interventionen. Diese Studie liefert Hinweise, inwieweit sich altersstufenbezogene Abweichungen bei der Bewältigung von modalitätsspezifischen Merk- und Lernaufgaben abbilden lassen. Es wird angenommen, dass sich diese besonders für die auditive Modalität zeigen. Methodik: Dafür wurden die Untertestleistungen von 403 Kindern einer Normstichprobe zum BASIC-MLT varianzanalytisch für den Faktor Alter (11 Jahrgänge von 6-16 Jahren) geprüft. Des Weiteren wurden Abweichungen der Altersgruppenmittelwerte auf Signifikanz geprüft. Ergebnisse: Die Varianzanalyse zeigt signifikante Werte für die auditiven Untertests «Geräuschfolgen» und «Wörter Lernen Delay», entsprechende paarweise Einzelvergleiche weisen für beide Untertests darauf hin, dass die Leistungen der Zehn- und Zwölfjährigen von den meisten anderen Altersgruppen abweichen. Schlussfolgerungen: Die Ergebnisse unterstützen die Annahme, dass sich Veränderungen besonders für auditive Merk- und Lernleistungen darstellen lassen und korrespondieren mit Befunden zu einer vergleichsweise späteren Ausreifung des phonologischen Gedächtnisses und einer Bevorzugung bildbasierter Merk- und Lernstrategien bei den bis Zehnjährigen. Aktuelle Studien legen nahe, dass eine zunehmende Aktivierung linkstemporaler Strukturen bis ins Erwachsenalter reicht und mit dem verstärkten Einsatz verbaler Strategien einhergeht.
Organisch bedingte psychische Störungen im Kindes- und Jugendalter - Vier Kasuistiken
Authors: Günther Thomas , Hagenah Ullrich , Herpertz-Dahlmann Beate , Konrad Kerstin
Published: November 2008

Zusammenfassung: Die Aufgaben der Neuropsychologie im Rahmen der Diagnostik von psychischen Störungen im Kindes- und Jugendalter hat sich in den letzten Jahren sehr verändert. Während es früher häufig um die Frage ging, ob bei dem jungen Patienten eine Hirnschädigung vorliegt oder nicht, ist diese Aufgabe heute aufgrund der besseren Möglichkeiten der bildgebenden Verfahren eher in den Hintergrund gerückt. Anhand von vier Einzelfällen wird verdeutlicht, dass frühe Hirnschädigungen nicht nur unmittelbar, sondern auch mittelbar zu Beeinträchtigungen führen. Insbesondere die mittelbaren Folgen, wie z.B. Verhaltensauffälligkeiten und persistierende neuropsychologische Defizite im Entwicklungsverlauf, sind häufig der Grund für eine klinische Vorstellung. Die Besonderheiten von kinder- und jugendpsychiatrischen Patienten mit organisch bedingten psychischen Störungen hinsichtlich Diagnostik und Therapieverlauf werden anhand der ausgewählten Kasuistiken ausführlich diskutiert.
Relationship between snow parameters and microwave satellite measurements: Theory compared with Advanced Microwave Sounding Unit observations from 23 to 150 GHz
Authors: Grody Norman
Published: November 2008

A theoretical model is used to examine the relationship between snow parameters and satellite‐based microwave radiometer measurements between 23 and 150 GHz. The model is based on the two‐stream radiative transfer equation whose optical parameters are obtained from dense media theory. Model simulations are used to show how the grain size, density, snow depth, and an ice crust affect the emissivity and brightness temperatures measured by the Advanced Microwave Sounding Unit (AMSU). The AMSU channels at 23, 31, 89, and 150 GHz are shown to be more sensitive to grain size variations than the other snow parameters. For ice particle diameters less than 1 mm the emissivity and brightness temperatures are found to decrease continuously up to 150 GHz. However, for larger particles, the emissivity and brightness temperature results in a flatter frequency response beyond 89 GHz as the wavelength approaches the particle size. Model results are tested using AMSU measurements for snow events over the central United States during a 2‐week period in the late fall. In agreement with model simulations, the brightness temperature is shown to decrease continuously up to 150 GHz for the small grain size associated with new snow, whereas the brightness temperature no longer decreases beyond 89 GHz as the snow ages and larger grains form owing to snow metamorphosis. Most importantly, the difference between the 89 and 150 GHz AMSU measurements is shown to provide a unique signature for identifying and separating new from aged snow. Consequently, it is now possible to identify four different snow types (wet, new, aged, and stratified snow) from AMSU.
Modeling of the solar radiative impact of biomass burning aerosols during the Dust and Biomass‐burning Experiment (DABEX)
Authors: Myhre G. , Hoyle C. R. , Berglen T. F. , Johnson B. T. , Haywood J. M.
Published: November 2008

The radiative forcing associated with biomass burning aerosols has been calculated over West Africa using a chemical transport model. The model simulations focus on the period of January∼February 2006 during the Dust and Biomass‐burning Experiment (DABEX). All of the main aerosol components for this region are modeled including mineral dust, biomass burning (BB) aerosols, secondary organic carbon associated with BB emissions, and carbonaceous particles from the use of fossil fuel and biofuel. The optical properties of the BB aerosol are specified using aircraft data from DABEX. The modeled aerosol optical depth (AOD) is within 15–20% of data from the few available Aerosol Robotic Network (AERONET) measurement stations. However, the model predicts very high AOD over central Africa, which disagrees somewhat with satellite retrieved AOD from Moderate Resolution Imaging Spectroradiometer (MODIS) and Multiangle Imaging Spectroradiometer (MISR). This indicates that BB emissions may be too high in central Africa or that very high AOD may be incorrectly screened out of the satellite data. The aerosol single scattering albedo increases with wavelength in our model and in AERONET retrievals, which contrasts with results from a previous biomass burning aerosol campaign. The model gives a strong negative radiative forcing of the BB aerosols at the top of the atmosphere (TOA) in clear‐sky conditions over most of the domain, except over the Saharan desert where surface albedos are high. The all‐sky TOA radiative forcing is quite inhomogeneous with values varying from −10 to 10 W m−2. The regional mean TOA radiative forcing is close to zero for the all‐sky calculation and around −1.5 W m−2 for the clear‐sky calculation. Sensitivity simulations indicate a positive regional mean TOA radiative forcing of up to 3 W m−2.
Automated algorithm for mapping regions of cold‐air pooling in complex terrain
Authors: Lundquist Jessica D. , Pepin Nicholas , Rochford Caitlin
Published: November 2008

In complex terrain, air in contact with the ground becomes cooled from radiative energy loss on a calm clear night and, being denser than the free atmosphere at the same elevation, sinks to valley bottoms. Cold‐air pooling (CAP) occurs where this cooled air collects on the landscape. This article focuses on identifying locations on a landscape subject to considerably lower minimum temperatures than the regional average during conditions of clear skies and weak synoptic‐scale winds, providing a simple automated method to map locations where cold air is likely to pool. Digital elevation models of regions of complex terrain were used to derive surfaces of local slope, curvature, and percentile elevation relative to surrounding terrain. Each pixel was classified as prone to CAP, not prone to CAP, or exhibiting no signal, based on the criterion that CAP occurs in regions with flat slopes in local depressions or valleys (negative curvature and low percentile). Along‐valley changes in the topographic amplification factor (TAF) were then calculated to determine whether the cold air in the valley was likely to drain or pool. Results were checked against distributed temperature measurements in Loch Vale, Rocky Mountain National Park, Colorado; in the Eastern Pyrenees, France; and in Yosemite National Park, Sierra Nevada, California. Using CAP classification to interpolate temperatures across complex terrain resulted in improvements in root‐mean‐square errors compared to more basic interpolation techniques at most sites within the three areas examined, with average error reductions of up to 3°C at individual sites and about 1°C averaged over all sites in the study areas.
On the response of Halogen Occultation Experiment (HALOE) stratospheric ozone and temperature to the 11‐year solar cycle forcing
Authors: Remsberg E. E.
Published: November 2008

Results are presented on responses in 14‐year (1991–2005) time series of stratospheric ozone and temperature from the Halogen Occultation Experiment (HALOE) of the Upper Atmosphere Research Satellite (UARS) to a solar cycle (SC‐like) variation. The ozone time series are for ten, 20‐degree‐wide, latitude bins from 45°S to 45°N and for thirteen “half‐Umkehr” layers of about 2.5 km thickness and extending from 63 hPa to 0.7 hPa. The temperature time series analyses were restricted to pressure levels in the range of 2 hPa to 0.7 hPa. Multiple linear regression (MLR) techniques were applied to each of the 130 time series of bin‐averaged, sunrise plus sunset ozone points over that latitude/pressure domain. A simple, 11‐year periodic term and a linear trend term were added to the final MLR models after their seasonal and interannual terms had been determined. Where the amplitudes of the 11‐year terms are significant, they are in phase with those of the more standard proxies for the solar UV flux. The maximum minus minimum response for ozone is on the order of 2 to 3% from about 2 to 5 hPa and for the latitudes of 45°S to 45°N. There is also a significant maximum minus minimum response on the order of 1 K for temperature between 15°S and 15°N and from 2 to 0.7 hPa. The associated linear trends for ozone are near zero in the upper stratosphere. It is noted, however, that effects of the changes in total chlorine during this 14‐year period were not accounted for explicitly and that their omission can be a confounding effect for both the analyzed solar cycle responses and the linear terms, especially for tropical upper stratospheric ozone. It is concluded that the solar occultation technique of HALOE provided adequate sampling and sufficient vertical resolution for obtaining the solar cycle response in stratospheric ozone.
Wavelengths, Transition Probabilities, and Energy Levels for the Spectra of Sodium (NaI–NaXI)
Authors: Sansonetti J. E.
Published: November 2008

Energy levels, with classifications and uncertainties, have been compiled for the spectra of the neutral atom and all positive ions of sodium (Z=11). Wavelengths with classifications, intensities, and transition probabilities are also tabulated. In addition, ground states and ionization energies are listed. Where available, the hyperfine structure constants and the percentages of the leading components of the energy levels are included. For all ionization stages of sodium, at least some experimental data are available; however, for those for which only a few transitions have been measured, theoretical calculations or values obtained by isoelectronic fitting are reported. Similarly, theoretical or isoelectronically determined ionization energies are given when they are thought to be more accurate than the available experimental data would produce.
Real-time x-ray diffraction measurements of shocked polycrystalline tin and aluminum
Authors: Morgan Dane V. , Macy Don , Stevens Gerald
Published: November 2008

A new, fast, single-pulse x-ray diffraction (XRD) diagnostic for determining phase transitions in shocked polycrystalline materials has been developed. The diagnostic consists of a 37-stage Marx bank high-voltage pulse generator coupled to a needle-and-washer electron beam diode via coaxial cable, producing line and bremsstrahlung x-ray emission in a 35 ns pulse. The characteristic Kα lines from the selected anodes of silver and molybdenum are used to produce the diffraction patterns, with thin foil filters employed to remove the characteristic Kβ line emission. The x-ray beam passes through a pinhole collimator and is incident on the sample with an approximately 3×6 mm2 spot and 1° full width half maximum angular divergence in a Bragg-reflecting geometry. For the experiments described in this report, the angle between the incident beam and the sample surface was 8.5°. A Debye–Scherrer diffraction image was produced on a phosphor located 76 mm from the polycrystalline sample surface. The phosphor image was coupled to a charge-coupled device camera through a coherent fiber-optic bundle. Dynamic single-pulse XRD experiments were conducted with thin foil samples of tin, shock loaded with a 1 mm vitreous carbon back window. Detasheet high explosive with a 2-mm-thick aluminum buffer was used to shock the sample. Analysis of the dynamic shock-loaded tin XRD images revealed a phase transformation of the tin beta phase into an amorphous or liquid state. Identical experiments with shock-loaded aluminum indicated compression of the face-centered-cubic aluminum lattice with no phase transformation.
Spatial ecology of the giant burrowing frog (Heleioporus australiacus): implications for conservation prescriptions
Authors: Penman Trent D. , Lemckert Frank L. , Mahony Michael J.
Published: November 2008

Management of threatened anurans requires an understanding of a species’ behaviour and habitat requirements in both the breeding and non-breeding environments. The giant burrowing frog (Heleioporus australiacus) is a threatened species in south-eastern Australia. Little is known about its habitat requirements, creating difficulties in developing management strategies for the species. We radio-tracked 33 individual H. australiacus in order to determine their habitat use and behaviour. Data from 33 frogs followed for between 5 and 599 days show that individuals spend little time near (<15 m) their breeding sites (mean 4.7 days for males and 6.3 days for females annually). Most time is spent in distinct non-breeding activity areas 20–250 m from the breeding sites. Activity areas of females were further from the breeding site (mean 143 m) than those of males (mean 99 m), but were not significantly different in size (overall mean 500 m2; males 553 m2; females 307 m2). Within activity areas, each frog used 1–14 burrows repeatedly, which we term home burrows. Existing prescriptions are inappropriate for this species and we propose protection of key populations in the landscape as a more appropriate means of protecting this species.
Electron tomography of early melanosomes: Implications for melanogenesis and the generation of fibrillar amyloid sheets
Authors: Hurbain Ilse , Geerts Willie J. C. , Boudier Thomas , Marco Sergio , Verkleij Arie J. , Marks Michael S. , Raposo Graç
Published: November 2008

Melanosomes are lysosome-related organelles (LROs) in which melanins are synthesized and stored. Early stage melanosomes are characterized morphologically by intralumenal fibrils upon which melanins are deposited in later stages. The integral membrane protein Pmel17 is a component of the fibrils, can nucleate fibril formation in the absence of other pigment cell-specific proteins, and forms amyloid-like fibrils in vitro. Before fibril formation Pmel17 traffics through multivesicular endosomal compartments, but how these compartments participate in downstream events leading to fibril formation is not fully known. By using high-pressure freezing of MNT-1 melanoma cells and freeze substitution to optimize ultrastructural preservation followed by double tilt 3D electron tomography, we show that the amyloid-like fibrils begin to form in multivesicular compartments, where they radiate from the luminal side of intralumenal membrane vesicles. The fibrils in fully formed stage II premelanosomes organize into sheet-like arrays and exclude the remaining intralumenal vesicles, which are smaller and often in continuity with the limiting membrane. These observations indicate that premelanosome fibrils form in association with intralumenal endosomal membranes. We suggest that similar processes regulate amyloid formation in pathological models.
Large negative linear compressibility of Ag
3
[Co(CN)
6
]
Authors: Goodwin Andrew L. , Keen David A. , Tucker Matthew G.
Published: November 2008

Silver(I) hexacyanocobaltate(III), Ag
3
[Co(CN)
6
], shows a large negative linear compressibility (NLC, linear expansion under hydrostatic pressure) at ambient temperature at all pressures up to our experimental limit of 7.65(2) GPa. This behavior is qualitatively unaffected by a transition at 0.19 GPa to a new phase Ag
3
[Co(CN)
6
]-II, whose structure is reported here. The high-pressure phase also shows anisotropic thermal expansion with large uniaxial negative thermal expansion (NTE, expansion on cooling). In both phases, the NLC/NTE effect arises as the rapid compression/contraction of layers of silver atoms—weakly bound via argentophilic interactions—is translated via flexing of the covalent network lattice into an expansion along a perpendicular direction. It is proposed that framework materials that contract along a specific direction on heating while expanding macroscopically will, in general, also expand along the same direction under hydrostatic pressure while contracting macroscopically.
Ordered cyclic motifs contribute to dynamic stability in biological and engineered networks
Authors: Ma'ayan Avi , Cecchi Guillermo A. , Wagner John , Rao A. Ravi , Iyengar Ravi , Stolovitzky Gustavo
Published: November 2008

Representation and analysis of complex biological and engineered systems as directed networks is useful for understanding their global structure/function organization. Enrichment of network motifs, which are over-represented subgraphs in real networks, can be used for topological analysis. Because counting network motifs is computationally expensive, only characterization of 3- to 5-node motifs has been previously reported. In this study we used a supercomputer to analyze cyclic motifs made of 3–20 nodes for 6 biological and 3 technological networks. Using tools from statistical physics, we developed a theoretical framework for characterizing the ensemble of cyclic motifs in real networks. We have identified a generic property of real complex networks, antiferromagnetic organization, which is characterized by minimal directional coherence of edges along cyclic subgraphs, such that consecutive links tend to have opposing direction. As a consequence, we find that the lack of directional coherence in cyclic motifs leads to depletion in feedback loops, where the number of nodes affected by feedback loops appears to be at a local minimum compared with surrogate shuffled networks. This topology provides more dynamic stability in large networks.
Complementarity in marine biodiversity manipulations: Reconciling divergent evidence from field and mesocosm experiments
Authors: Stachowicz John J. , Best Rebecca J. , Bracken Matthew E. S. , Graham Michael H.
Published: November 2008

Mounting concern over the loss of marine biodiversity has increased the urgency of understanding its consequences. This urgency spurred the publication of many short-term studies, which often report weak effects of diversity (species richness) driven by the presence of key species (the sampling effect). Longer-term field experiments are slowly accumulating, and they more often report strong diversity effects driven by species complementarity, calling into question the generality of earlier findings. However, differences among study systems in which short- and long-term studies are conducted currently limit our ability to assess whether these differences are simply due to biological or environmental differences among systems. In this paper, we compared the effect of intertidal seaweed species richness on biomass accumulation in mesocosms and field experiments using the same pool of species. We found that seaweed species richness increased biomass accumulation in field experiments in both short (2-month) and long (3-year) experiments, although effects were stronger in the long-term experiment. In contrast, richness had no effect in mesocosm experiments, where biomass accumulation was completely a function of species identity. We argue that the short-term experiments, like many published experiments on the topic, detect only a subset of possible mechanisms that operate in the field over the longer term because they lack sufficient environmental heterogeneity to allow expression of niche differences, and they are of insufficient length to capture population-level responses, such as recruitment. Many published experiments, therefore, likely underestimate the strength of diversity on ecosystem processes in natural ecosystems.