bluuebunny/crossref_metadata_2025 huggingface dataset:
Characteristics and potential applications of coarse clay fractions from Puolanka, Finland
Authors: Leiviskä Tiina , Gehör Seppo , Eijärvi Erkki , Sarpola Arja , Tanskanen Juha
Published: April 2012

Characterization of coarse fractions of kaolin clay from two locations in Puolanka (Pihlajavaara and Poskimäki) was performed in order to find potential applications for these materials in water and wastewater treatment as low-cost adsorbents or as a raw material for other uses. The effects of wet and dry fractionation methods and the annealing of the sample on the properties of the coarse fractions were studied. The coarse fractions contained mainly quartz, while the kaolinite content was considered low. The Poskimäki (PM) clay had a higher specific surface area (SSA) and cation exchange capacities (CEC) than the Pihlajavaara (PV) clay due to a higher amount of iron. Annealing (800°C) decreased the SSA and CEC. The fractionation method had only a minor effect on particle size distribution. PV and PM colloidal suspensions had a negative zeta potential at natural pH values. Very small amounts of contained elements (Al, Si, Ca, Mg, K, Cd, Co, Fe, Mn, Cr, Ni, Cu, Zn, Pb, Ba) were dissolved from samples at natural pH values. PM clay could be utilized in water treatment for example as a raw material in iron oxide-coated sands. For this purpose, the wet fractionated samples had a higher content of iron than the dry fractionated samples.
Gender, Citizenship, and Women's ‘Unskilled’ Labour: The Experience of Filipino Migrant Nurses in Singapore
Authors: Choi Seori , Lyons Lenore
Published: April 2012

Les cadres juridiques qui régissent le déploiement des migrantes dans les marchés du travail domestique entravent souvent l'accès de ces dernières aux droits à la citoyenneté dans les pays d'accueil. La distinction entre la travailleuse « qualifiée » et « non qualifiée » s'inscrit dans les régimes du travail et de l'immigration qui en revanche déterminent les conditions de travail des migrantes (y compris les salaires, les heures de travail, les jours de congé, etc.), et leur liberté de circulation, leur capacité à se marier et à parrainer les membres de leurs familles, ainsi que leur admissibilité à la résidence permanente et en dernier ressort, à la citoyenneté. Dans le cas de Singapour, l'État tente d'améliorer les compétences de sa main-d'œuvre par l'entremise d'un régime d'immigration qui classe les travailleuses non citoyennes selon leur salaire. À l'aide d'un système à trois niveaux pour admettre des travailleuses non citoyennes, l'État classe les migrantes dans les catégories suivantes : professionnelles (titulaires de titre d'emploi—employment pass), travailleuses à compétence moyenne (titulaires de titre S—S pass) et travailleuses non qualifiées (titulaires de permis de travail—work permit). Ces trois catégories représentent une division du travail selon le genre dans le marché de l'emploi, entraînant des conséquences pour les migrantes à Singapour. Se fondant sur des études faites auprès des migrantes philippines qui travaillent à Singapour, le présent article explore comment le programme singapourien visant la main-d'œuvre migrante et fondé sur les compétences porte atteinte aux droits du travail et aux droits sociaux des infirmières migrantes. Notre analyse explore la place de la profession d'infirmière dans les régimes du travail, de l'immigration et de l'éducation. Nous avançons que le programme singapourien d'importation de la main-d'œuvre à plusieurs niveaux renforce la perception commune du public selon laquelle toutes les Philippines sont des « domestiques », donnant aux infirmières migrantes un statut ambigu, quelque part entre les catégories de travailleuses qualifiées ou non qualifiées. Bien que l'entre-deux des infirmières migrantes structure leur expérience de migration, il offre aussi un site de résistance.
Discrimination systémique et intersectionnalité : la déqualification des immigrantes à Montréal
Authors: Chicha Marie-Thérèse
Published: April 2012

Since the early 1990s, Canada and Québec have been selecting immigration candidates primarily on the basis of their professional qualifications, including any diplomas they hold, their professional experience, and their linguistic abilities. Paradoxically, statistics show that the professional status of women immigrants who have arrived since that time has been deteriorating and that they are more susceptible to experiencing a high unemployment rate, low income, and precarious working conditions. One of the particularly worrisome aspects of this situation is the fact that despite their high qualifications, more and more women immigrants are permanently occupying jobs for which they are over-qualified. The author presents the results of research that explores the downgrading of women immigrants who hold a foreign university degree and who live in Montreal. The significance of this research is that, through a systemic approach, it attempts to better understand why some women immigrants experience a higher level of downgrading, while others manage to escape this predicament.
Cashing in on Cachet? Ethnicity and Gender in the Strip Club
Authors: Law Tuulia
Published: April 2012

Quelque part entre les pervers pépères, le culte de la culture populaire, les images sensationnalistes des médias et la politique canadienne en matière d'immigration, la danseuse nue roumaine est devenue une sorte d'archétype. Attrayante, sensuelle, avec son accent étranger excitant et sa peau blanche, elle est la parfaite danseuse exotique. Les danseuses nues représentent le genre, la sensualité ou la sexualité, l'émotion et souvent, l'ethnicité. L'ethnicité peut avoir un cachet dans l'industrie du sexe, et comme le genre, les travailleuses usent consciemment de leur ethnicité pour tirer profit de ce cachet. Les danseuses nues roumaines sont bien placées pour ce faire, car elles sont, au contraire des femmes de couleur, « différentes », mais pas trop. En conséquence, la préférence des clients et de la direction des clubs pour les danseuses roumaines a entraîné la création d'un archétype et la fabrication d'une pénurie de danseuses nues pour répondre à cette demande préférentielle. À l'aide d'une analyse interdépendante de la race, du genre, de l'ethnicité, de la stigmatisation et de la classe, l'auteure explore le discours sur « l'altérité acceptable » implicite dans le traitement et la perception des danseuses nues roumaines par les clients et les directeurs de clubs et le gouvernement canadien, ainsi que par le public.
Mandatory Family Mediation and the Settlement Mission: A Feminist Critique
Authors: Semple Noel
Published: April 2012

En Amérique du Nord, les conflits familiaux font très souvent l'objet de médiation où une tierce partie neutre tente de trouver avec les époux une résolution volontaire de leurs différends. La médiation familiale compte de nombreux partisans et de nombreuses partisanes enthousiastes, et dans plusieurs juridictions, elle constitue un passage obligé avant d'entreprendre les procédures traditionnelles. Cependant, elle a aussi donné lieu à une critique féministe puissante qui considère le déséquilibre des pouvoirs et la violence familiale comme des sources d'exploitation et de résultats injustes obtenus par la médiation. Le présent article synthétise la critique féministe de la médiation familiale, et évalue les efforts faits dans la pratique de la médiation contemporaine pour y répondre. Même en l'absence de médiation familiale formelle, les juges et les autres travailleurs et travailleuses de l'appareil judiciaire en matière familiale soumettront vraisemblablement les époux en litige à des pressions informelles pour trouver un règlement. Le présent article défend l'idée que la critique féministe est peut-être plus pertinente à cette « mission de règlement » qu'à la médiation familiale formelle telle qu'elle se pratique de nos jours.
Veterinary Medical Education and Veterinary Involvement in Aquatic-Animal Health and Aquaculture in Mexico
Authors: Ortega S. César
Published: April 2012

This article analyzes curriculum offerings related to aquaculture and/or aquatic-animal health taught in veterinary medical schools or colleges in Mexico. The information database of the Mexican Association of Schools and Colleges of Veterinary Medicine and the Web sites of veterinary institutions indicate that 60% of veterinary colleges include courses related to aquaculture in their curriculum, but most of these are optional courses. There are few specialized continuing education programs or graduate level courses. There is also a lack of veterinary participation, in both public and private sectors, in aquatic-animal health. It is evident that there should be a greater involvement by the veterinary profession in Mexico's aquaculture to ensure food production in a safe and sustainable manner; to achieve this, veterinary medical institutions must include more aquaculture and aquatic-animal health courses in their curricula.
An Online Algorithm for Lightweight Grammar-Based Compression
Authors: Maruyama Shirou , Sakamoto Hiroshi , Takeda Masayuki
Published: April 2012

Grammar-based compression is a well-studied technique to construct a context-free grammar (CFG) deriving a given text uniquely. In this work, we propose an online algorithm for grammar-based compression. Our algorithm guarantees O(log2 n)- approximation ratio for the minimum grammar size, where n is an input size, and it runs in input linear time and output linear space. In addition, we propose a practical encoding, which transforms a restricted CFG into a more compact representation. Experimental results by comparison with standard compressors demonstrate that our algorithm is especially effective for highly repetitive text.
Content Sharing Graphs for Deduplication-Enabled Storage Systems
Authors: Lu Maohua , Constantinescu Cornel , Sarkar Prasenjit
Published: April 2012

Deduplication in storage systems has gained momentum recently for its capability in reducing data footprint. However, deduplication introduces challenges to storage management as storage objects (e.g., files) are no longer independent from each other due to content sharing between these storage objects. In this paper, we present a graph-based framework to address the challenges of storage management due to deduplication. Specifically, we model content sharing among storage objects by content sharing graphs (CSG), and apply graph-based algorithms to two real-world storage management use cases for deduplication-enabled storage systems. First, a quasi-linear algorithm was developed to partition deduplication domains with a minimal amount of deduplication loss (i.e., data replicated across partitioned domains) in commercial deduplication-enabled storage systems, whereas in general the partitioning problem is NP-complete. For a real-world trace of 3 TB data with 978 GB of removable duplicates, the proposed algorithm can partition the data into 15 balanced partitions with only 54 GB of deduplication loss, that is, a 5% deduplication loss. Second, a quick and accurate method to query the deduplicated size for a subset of objects in deduplicated storage systems was developed. For the same trace of 3 TB data, the optimized graph-based algorithm can complete the query in 2.6 s, which is less than 1% of that of the traditional algorithm based on the deduplication metadata.
A Review of Social Media Use in E-Government
Authors: Magro Michael J.
Published: April 2012

In the past few years, e-government has been a topic of much interest among those excited about the advent of Web 2.0 technologies. This paper reviews the recent literature concerning Web 2.0, social media, social networking, and how it has been used in the public sector. Key observations include literature themes such as the evolution of social media case studies in the literature, the progress of social media policies and strategies over time, and social media use in disaster management as an important role for government. Other observations include the lack of a tangible goal for e-government, and the idea that significant change is still needed in government culture, philosophy of control, and resource management before broad sustainable success can be achieved in the use of social media.
Application of Liquid-Phase Direct Fluorination: Novel Synthetic Methods for a Polyfluorinated Coating Material and a Monomer of a Perfluorinated Polymer Electrolyte Membrane
Authors: Okazoe Takashi , Shirakawa Daisuke , Murata Koichi
Published: April 2012

A new polyfluorinated anti-staining coating material CF3O(CF2CF2O)xCF2-CONHCH2CH2CH2Si(OCH3)3 has been developed by utilizing the PERFECT method, which employs a liquid-phase direct fluorination reaction with elemental fluorine as a key step. Direct fluorination of a partially-fluorinated ester, which was prepared from a non-fluorinated poly(ethylene glycol) and a perfluorinated acyl fluoride, followed by methanolysis, gave the perfluorinated corresponding compound, which was led to the coating material for surface treating agents, and the methyl ester of the starting perfluorinated acyl fluoride. Application to the synthesis of a new perfluorinated bifunctional sulfonate monomer CF2=CFOCF2CF2CF2OCF(CF2SO2F)2 for polymer electrolyte membranes (PEMs) of fuel cells was also developed.
Tsallis Relative Entropy and Anomalous Diffusion
Authors: Prehl Janett , Essex Christopher , Hoffmann Karl Heinz
Published: April 2012

In this paper we utilize the Tsallis relative entropy, a generalization of the Kullback–Leibler entropy in the frame work of non-extensive thermodynamics to analyze the properties of anomalous diffusion processes. Anomalous (super-) diffusive behavior can be described by fractional diffusion equations, where the second order space derivative is extended to fractional order α ∈ (1, 2). They represent a bridging regime, where for α = 2 one obtains the diffusion equation and for α = 1 the (half) wave equation is given. These fractional diffusion equations are solved by so-called stable distributions, which exhibit heavy tails and skewness. In contrast to the Shannon or Tsallis entropy of these distributions, the Kullback and Tsallis relative entropy, relative to the pure diffusion case, induce a natural ordering of the stable distributions consistent with the ordering implied by the pure diffusion and wave limits.
Fly Ash Porous Material using Geopolymerization Process for High Temperature Exposure
Authors: Abdullah Mohd Mustafa Al Bakri , Jamaludin Liyana , Hussin Kamarudin , Bnhussain Mohamed , Ghazali Che Mohd Ruzaidi , Ahmad Mohd Izzat
Published: April 2012

This paper presents the results of a study on the effect of temperature on geopolymers manufactured using pozzolanic materials (fly ash). In this paper, we report on our investigation of the performance of porous geopolymers made with fly ash after exposure to temperatures from 600 °C up to 1000 °C. The research methodology consisted of pozzolanic materials (fly ash) synthesized with a mixture of sodium hydroxide and sodium silicate solution as an alkaline activator. Foaming agent solution was added to geopolymer paste. The geopolymer paste samples were cured at 60 °C for one day and the geopolymers samples were sintered from 600 °C to 1000 °C to evaluate strength loss due to thermal damage. We also studied their phase formation and microstructure. The heated geopolymers samples were tested by compressive strength after three days. The results showed that the porous geopolymers exhibited strength increases after temperature exposure.
Density Functional Theory (DFT) Study of Triphenylamine-Based Dyes for Their Use as Sensitizers in Molecular Photovoltaics
Authors: Baldenebro-López Jesús , Castorena-González José , Flores-Holguín Norma , Almaral-Sánchez Jorge , Glossman-Mitnik Daniel
Published: April 2012

In this work we studied three dyes which are proposed for potential photovoltaic applications and named Dye7, Dye7-2t and Dye7-3t. The Density Functional Theory (DFT) was utilized, using the M05-2X hybrid meta-GGA functional and the 6–31+G(d,p) basis set. This level of calculation was used to find the optimized molecular structure and to predict the main molecular vibrations, the absorption and emission spectra, the molecular orbitals energies, dipole moment, isotropic polarizability and the chemical reactivity parameters that arise from Conceptual DFT. Also, the pKa values were calculated with the semi-empirical PM6 method.
Combining Molecular Docking and Molecular Dynamics to Predict the Binding Modes of Flavonoid Derivatives with the Neuraminidase of the 2009 H1N1 Influenza A Virus
Authors: Lu Shih-Jen , Chong Fok-Ching
Published: April 2012

Control of flavonoid derivatives inhibitors release through the inhibition of neuraminidase has been identified as a potential target for the treatment of H1N1 influenza disease. We have employed molecular dynamics simulation techniques to optimize the 2009 H1N1 influenza neuraminidase X-ray crystal structure. Molecular docking of the compounds revealed the possible binding mode. Our molecular dynamics simulations combined with the solvated interaction energies technique was applied to predict the docking models of the inhibitors in the binding pocket of the H1N1 influenza neuraminidase. In the simulations, the correlation of the predicted and experimental binding free energies of all 20 flavonoid derivatives inhibitors is satisfactory, as indicated by R2 = 0.75.
Enhancement of Mechanical and Thermal Properties of Polycaprolactone/Chitosan Blend by Calcium Carbonate Nanoparticles
Authors: Abdolmohammadi Sanaz , Siyamak Samira , Ibrahim Nor Azowa , Yunus Wan Md Zin Wan , Rahman Mohamad Zaki Ab , Azizi Susan , Fatehi Asma
Published: April 2012

This study investigates the effects of calcium carbonate (CaCO3) nanoparticles on the mechanical and thermal properties and surface morphology of polycaprolactone (PCL)/chitosan nanocomposites. The nanocomposites of PCL/chitosan/CaCO3 were prepared using a melt blending technique. Transmission electron microscopy (TEM) results indicate the average size of nanoparticles to be approximately 62 nm. Tensile measurement results show an increase in the tensile modulus with CaCO3 nanoparticle loading. Tensile strength and elongation at break show gradual improvement with the addition of up to 1 wt% of nano-sized CaCO3. Decreasing performance of these properties is observed for loading of more than 1 wt% of nano-sized CaCO3. The thermal stability was best enhanced at 1 wt% of CaCO3 nanoparticle loading. The fractured surface morphology of the PCL/chitosan blend becomes more stretched and homogeneous in PCL/chitosan/CaCO3 nanocomposite. TEM micrograph displays good dispersion of CaCO3 at lower nanoparticle loading within the matrix.
Extreme Multiple Reticulate Origins of the Pteris cadieri Complex (Pteridaceae)
Authors: Chao Yi-Shan , Dong Shi-Yong , Chiang Yu-Chung , Liu Ho-Yih , Chiou Wen-Liang
Published: April 2012

The Pteris cadieri complex displays extensive morphological variation and seems to have originated through hybridization. However, the members of this complex reproduce by apogamy, which usually limits genetic variation. To evaluate the hypotheses of hybrid origins, the pattern of evolution in this species complex is reconstructed. Multiple methodologies were used. Diploids, triploids, and tetraploids were identified by chromosome counts and flow cytometry. Nuclear DNA markers (cytosolic phosphoglucose isomerase gene, PgiC) were used, together with chloroplast DNA markers (atpB-rbcL spacer and rbcL gene) to infer the biparental and maternal lineages of the Pteris cadieri complex. The three cpDNA haplotype groups and five PgiC alleles found in this study indicate that the evolution of the Pteris cadieri complex has been extremely reticulate. Up to 11 taxa belonging to eight morphs were identified. By comparing genetic variation in the Pteris cadieri in two independent areas, Hainan and Taiwan, we inferred that hybridization has occurred independently in different areas. Furthermore, we found evidence for phenological divergence (evergreen and deciduous) within Taiwan. We propose that the Pteris cadieri complex originated from different genetic lineages through multiple hybridizations in different geographical areas, leading to its present morphological diversity.
Identiﬁcation of Novel Potential β-N-Acetyl-D-Hexosaminidase Inhibitors by Virtual Screening, Molecular Dynamics Simulation and MM-PBSA Calculations
Authors: Liu Jianling , Liu Mengmeng , Yao Yao , Wang Jinan , Li Yan , Li Guohui , Wang Yonghua
Published: April 2012

Chitinolytic β-N-acetyl-D-hexosaminidases, as a class of chitin hydrolysis enzyme in insects, are a potential species-specific target for developing environmentally-friendly pesticides. Until now, pesticides targeting chitinolytic β-N-acetyl-D-hexosaminidase have not been developed. This study demonstrates a combination of different theoretical methods for investigating the key structural features of this enzyme responsible for pesticide inhibition, thus allowing for the discovery of novel small molecule inhibitors. Firstly, based on the currently reported crystal structure of this protein (OfHex1.pdb), we conducted a pre-screening of a drug-like compound database with 8 × 106 compounds by using the expanded pesticide-likeness criteria, followed by docking-based screening, obtaining 5 top-ranked compounds with favorable docking conformation into OfHex1. Secondly, molecular docking and molecular dynamics simulations are performed for the five complexes and demonstrate that one main hydrophobic pocket formed by residues Trp424, Trp448 and Trp524, which is significant for stabilization of the ligand–receptor complex, and key residues Asp477 and Trp490, are respectively responsible for forming hydrogen-bonding and π–π stacking interactions with the ligands. Finally, the molecular mechanics Poisson–Boltzmann surface area (MM-PBSA) analysis indicates that van der Waals interactions are the main driving force for the inhibitor binding that agrees with the fact that the binding pocket of OfHex1 is mainly composed of hydrophobic residues. These results suggest that screening the ZINC database can maximize the identification of potential OfHex1 inhibitors and the computational protocol will be valuable for screening potential inhibitors of the binding mode, which is useful for the future rational design of novel, potent OfHex1-specific pesticides.
Trophic Interactions Between Insects and Stream-Associated Amphibians in Steep, Cobble-Bottom Streams of the Pacific Coast of North America
Authors: Atwood Trisha , Richardson John S.
Published: April 2012

Two native, stream-associated amphibians are found in coastal streams of the west coast of North America, the tailed frog and the coastal giant salamander, and each interacts with stream insects in contrasting ways. For tailed frogs, their tadpoles are the primary life stage found in steep streams and they consume biofilm from rock surfaces, which can have trophic and non-trophic effects on stream insects. By virtue of their size the tadpoles are relatively insensitive to stream insect larvae, and tadpoles are capable of depleting biofilm levels directly (exploitative competition), and may also “bulldoze” insect larvae from the surfaces of stones (interference competition). Coastal giant salamander larvae, and sometimes adults, are found in small streams where they prey primarily on stream insects, as well as other small prey. This predator-prey interaction with stream insects does not appear to result in differences in the stream invertebrate community between streams with and without salamander larvae. These two examples illustrate the potential for trophic and non-trophic interactions between stream-associated amphibians and stream insects, and also highlights the need for further research in these systems.
Molecular Therapeutic Advances in Personalized Therapy of Melanoma and Non-Small Cell Lung Cancer
Authors: Kelleher Fergal C. , Solomon Benjamin , McArthur Grant A.
Published: April 2012

The incorporation of individualized molecular therapeutics into routine clinical practice for both non-small cell lung cancer (NSCLC) and melanoma are amongst the most significant advances of the last decades in medical oncology. In NSCLC activating somatic mutations in exons encoding the tyrosine kinase domain of the Epidermal Growth Factor Receptor (EGFR) gene have been found to be predictive of a response to treatment with tyrosine kinase inhibitors (TKI), erlotinib or gefitinib. More recently the EML4-ALK fusion gene which occurs in 3–5% of NSCLC has been found to predict sensitivity to crizotinib an inhibitor of the anaplastic lymphoma kinase (ALK) receptor tyrosine kinase. Similarly in melanoma, 50% of cases have BRAF mutations in exon 15 mostly V600E and these cases are sensitive to the BRAF inhibitors vemurafenib or dabrafenib. In a Phase III study of advanced melanoma cases with this mutation vemurafenib improved survival from 64% to 84% at 6 months, when compared with dacarbazine. In both NSCLC and melanoma clinical benefit is not obtained in patients without these genomic changes, and moreover in the case of vemurafenib the therapy may theoretically induce proliferation of cases of melanoma without BRAF mutations. An emerging clinical challenge is that of acquired resistance after initial responses to targeted therapeutics. Resistance to the TKI’s in NSCLC is most frequently due to acquisition of secondary mutations within the tyrosine kinase of the EGFR or alternatively activation of alternative tyrosine kinases such as C-MET. Mechanisms of drug resistance in melanoma to vemurafenib do not involve mutations in BRAF itself but are associated with a variety of molecular changes including RAF1 or COT gene over expression, activating mutations in RAS or increased activation of the receptor tyrosine kinase PDGFRβ. Importantly these data support introducing re-biopsy of tumors at progression to continue to personalize the choice of therapy throughout the patient’s disease course.
First Total Synthesis of a Naturally Occurring Iodinated 5′-Deoxyxylofuranosyl Marine Nucleoside
Authors: Sun Jianyun , Dou Yanhui , Ding Haixin , Yang Ruchun , Sun Qi , Xiao Qiang
Published: April 2012

4-Amino-7-(5′-deoxy-β-d-xylofuranosyl)-5-iodo-pyrrolo[2,3-d]pyrimidine 1, an unusual naturally occurring marine nucleoside isolated from an ascidan, Diplosoma sp., was synthesized from d-xylose in seven steps with 28% overall yield on 10 g scale. The key step was Vorbrüggen glycosylation of 5-iodo-pyrrolo[2,3-d]pyrimidine with 5-deoxy-1, 2-O-diacetyl-3-O-benzoyl-d-xylofuranose. Its absolute configuration was confirmed.
Design Issues for Low Power Integrated Thermal Flow Sensors with Ultra-Wide Dynamic Range and Low Insertion Loss
Authors: Bruschi Paolo , Piotto Massimo
Published: April 2012

Flow sensors are the key elements in most systems for monitoring and controlling fluid flows. With the introduction of MEMS thermal flow sensors, unprecedented performances, such as ultra wide measurement ranges, low power consumptions and extreme miniaturization, have been achieved, although several critical issues have still to be solved. In this work, a systematic approach to the design of integrated thermal flow sensors, with specification of resolution, dynamic range, power consumption and pressure insertion loss is proposed. All the critical components of the sensors, namely thermal microstructure, package and read-out interface are examined, showing their impact on the sensor performance and indicating effective optimization strategies. The proposed design procedures are supported by experiments performed using a recently developed test chip,including several different sensing structures and a flexible electronic interface.
New Methodology for the Synthesis of Thiobarbiturates Mediated by Manganese(III) Acetate
Authors: Bouhlel Ahlem , Curti Christophe , Vanelle Patrice
Published: April 2012

A three step synthesis of various thiobarbiturate derivatives 17–24 was established. The first step is mediated by Mn(OAc)3, in order to generate a carbon-carbon bond between a terminal alkene and malonate. Derivatives 1–8 were obtained in moderate to good yields under mild conditions. This key step allows synthesis of a wide variety of lipophilic thiobarbiturates, which could be tested for their anticonvulsive or anesthesic potential.
Repeated Dose 28-Days Oral Toxicity Study of Carica papaya L. Leaf Extract in Sprague Dawley Rats
Authors: Afzan Adlin , Abdullah Noor Rain , Halim Siti Zaleha , Rashid Badrul Amini , Semail Raja Hazlini Raja , Abdullah Noordini , Jantan Ibrahim , Muhammad Hussin , Ismail Zakiah
Published: April 2012

Carica papaya L. leaves have been used in ethnomedicine for the treatment of fevers and cancers. Despite its benefits, very few studies on their potential toxicity have been described. The aim of the present study was to characterize the chemical composition of the leaf extract from ‘Sekaki’ C. papaya cultivar by UPLC-TripleTOF-ESI-MS and to investigate the sub-acute oral toxicity in Sprague Dawley rats at doses of 0.01, 0.14 and 2 g/kg by examining the general behavior, clinical signs, hematological parameters, serum biochemistry and histopathology changes. A total of twelve compounds consisting of one piperidine alkaloid, two organic acids, six malic acid derivatives, and four flavonol glycosides were characterized or tentatively identified in the C. papaya leaf extract. In the sub-acute study, the C. papaya extract did not cause mortality nor were treatment-related changes in body weight, food intake, water level, and hematological parameters observed between treatment and control groups. Some biochemical parameters such as the total protein, HDL-cholesterol, AST, ALT and ALP were elevated in a non-dose dependent manner. Histopathological examination of all organs including liver did not reveal morphological alteration. Other parameters showed non-significant differences between treatment and control groups. The present results suggest that C. papaya leaf extract at a dose up to fourteen times the levels employed in practical use in traditional medicine in Malaysia could be considered safe as a medicinal agent.
Bio-Functional Constituents from the Stems of Liriodendron tulipifera
Authors: Chiu Chien-Chih , Chou Han-Lin , Wu Pei-Fang , Chen Hsin-Liang , Wang Hui-Min , Chen Chung-Yi
Published: April 2012

Four known compounds have been isolated from the stems of Liriodendron tulipifera, and the structures of these pure constituents were determined using spectroscopic analysis. Isolated compounds were screened for free radical scavenging ability, metal chelating power assay and ferric reducing antioxidant power assay (FRAP). The anti-tyrosinase effects of L. tulipifera compounds were calculated the inhibition of hydroxylation of L-tyrosine to L-dopa according to an in vitro mushroom tyrosinase assay. The study also examined the bio-effects of the four compounds on the human melanoma A375.S2, and showed that liriodenine (1) and (-)-norglaucine (4) significantly inhibited the proliferation of melanoma cells in the cell viability assay. Wound healing results indicated that liriodenine (1), (-)-glaucine (3) and (-)-norglaucine (4) exerted anti-migration potential. Interestingly, (-)-glaucine (3), neither liriodenine (1) nor (-)-norglaucine (4) showed promising anti-migration potential without inducing significant cytotoxicity. Furthermore, a dramatically increased level of intracellular reactive oxygen species (ROS) was detected from (-)-glaucine (3). The cell cycle assessment demonstrated a moderate G2/M accumulation by (-)-glaucine (3). The above results revealed the anti-cancer effects of L. tulipifera compounds, especially on the anti-migration ability indicating the promising chemopreventive agents to human skin melanoma cells.
Pressure and Temperature Spin Crossover Sensors with Optical Detection
Authors: Linares Jorge , Codjovi Epiphane , Garcia Yann
Published: April 2012

Iron(II) spin crossover molecular materials are made of coordination centres switchable between two states by temperature, pressure or a visible light irradiation. The relevant macroscopic parameter which monitors the magnetic state of a given solid is the high-spin (HS) fraction denoted nHS, i.e., the relative population of HS molecules. Each spin crossover material is distinguished by a transition temperature T1/2 where 50% of active molecules have switched to the low-spin (LS) state. In strongly interacting systems, the thermal spin switching occurs abruptly at T1/2. Applying pressure induces a shift from HS to LS states, which is the direct consequence of the lower volume for the LS molecule. Each material has thus a well defined pressure value P1/2. In both cases the spin state change is easily detectable by optical means thanks to a thermo/piezochromic effect that is often encountered in these materials. In this contribution, we discuss potential use of spin crossover molecular materials as temperature and pressure sensors with optical detection. The ones presenting smooth transitions behaviour, which have not been seriously considered for any application, are spotlighted as potential sensors which should stimulate a large interest on this well investigated class of materials.
Evaluation of Commercial Probes for On-Line Electrical Conductivity Measurements during Goat Gland Milking Process
Authors: Romero Gema , Díaz Jose Ramon , Sabater Jose Maria , Perez Carlos
Published: April 2012

The measurement of the milk electrical conductivity (EC) during mechanical milking has been widely studied for mastitis detection on cows because its improving of welfare and animal health, although research about small ruminants is scarce. The aim of this study was to evaluate the performance of three commercial conductimeters to be used during mechanical milking of small ruminant halves, especially Murciano-Granadina goats. The objective of this research was to integrate the probes on the milking unit and to check the suitability of the probe selected. The results presented in this research have guided authors to discard the commercial probes and to establish the requirements of a new probe design that is briefly outlined in the conclusions of this contribution.
An Instrument for In Situ Measuring the Volume Scattering Function of Water: Design, Calibration and Primary Experiments
Authors: Li Cai , Cao Wenxi , Yu Jing , Ke Tiancun , Lu Guixin , Yang Yuezhong , Guo Chaoying
Published: April 2012

The optical volume scattering function (VSF) of seawater is a fundamental property used in the calculation of radiative transfer for applications in the study of the upper-ocean heat balance, the photosynthetic productivity of the ocean, and the chemical transformation of photoreactive compounds. A new instrument to simultaneously measure the VSF in seven directions between 20° to 160°, the attenuation coefficient, and the depth of water is presented. The instrument is self-contained and can be automatically controlled by the depth under water. The self-contained data can be easily downloaded by an ultra-short-wave communication system. A calibration test was performed in the laboratory based on precise estimation of the scattering volume and optical radiometric calibration of the detectors. The measurement error of the VSF measurement instrument has been estimated in the laboratory based on the Mie theory, and the average error is less than 12%. The instrument was used to measure and analyze the variation characteristics of the VSF with angle, depth and water quality in Daya Bay for the first time. From these in situ data, we have found that the phase functions proposed by Fournier-Forand, measured by Petzold in San Diego Harbor and Sokolov in Black Sea do not fit with our measurements in Daya. These discrepancies could manly due to high proportion of suspended calcium carbonate mineral-like particles with high refractive index in Daya Bay.
A Neural Network Approach to Smarter Sensor Networks for Water Quality Monitoring
Authors: O’Connor Edel , Smeaton Alan F. , O’Connor Noel E. , Regan Fiona
Published: April 2012

Environmental monitoring is evolving towards large-scale and low-cost sensor networks operating reliability and autonomously over extended periods of time. Sophisticated analytical instrumentation such as chemo-bio sensors present inherent limitations because of the number of samples that they can take. In order to maximize their deployment lifetime, we propose the coordination of multiple heterogeneous information sources. We use rainfall radar images and information from a water depth sensor as input to a neural network (NN) to dictate the sampling frequency of a phosphate analyzer at the River Lee in Cork, Ireland. This approach shows varied performance for different times of the year but overall produces output that is very satisfactory for the application context in question. Our study demonstrates that even with limited training data, a system for controlling the sampling rate of the nutrient sensor can be set up and can improve the efficiency of the more sophisticated nodes of the sensor network.
Precise Temperature Mapping of GaN-Based LEDs by Quantitative Infrared Micro-Thermography
Authors: Chang Ki Soo , Yang Sun Choel , Kim Jae-Young , Kook Myung Ho , Ryu Seon Young , Choi Hae Young , Kim Geon Hee
Published: April 2012

A method of measuring the precise temperature distribution of GaN-based light-emitting diodes (LEDs) by quantitative infrared micro-thermography is reported. To reduce the calibration error, the same measuring conditions were used for both calibration and thermal imaging; calibration was conducted on a highly emissive black-painted area on a dummy sapphire wafer loaded near the LED wafer on a thermoelectric cooler mount. We used infrared thermal radiation images of the black-painted area on the dummy wafer and an unbiased LED wafer at two different temperatures to determine the factors that degrade the accuracy of temperature measurement, i.e., the non-uniform response of the instrument, superimposed offset radiation, reflected radiation, and emissivity map of the LED surface. By correcting these factors from the measured infrared thermal radiation images of biased LEDs, we determined a precise absolute temperature image. Consequently, we could observe from where the local self-heat emerges and how it distributes on the emitting area of the LEDs. The experimental results demonstrated that highly localized self-heating and a remarkable temperature gradient, which are detrimental to LED performance and reliability, arise near the p-contact edge of the LED surface at high injection levels owing to the current crowding effect.
Plant Insecticidal Toxins in Ecological Networks
Authors: Ibanez Sébastien , Gallet Christiane , Després Laurence
Published: April 2012

Plant secondary metabolites play a key role in plant-insect interactions, whether constitutive or induced, C- or N-based. Anti-herbivore defences against insects can act as repellents, deterrents, growth inhibitors or cause direct mortality. In turn, insects have evolved a variety of strategies to act against plant toxins, e.g., avoidance, excretion, sequestration and degradation of the toxin, eventually leading to a co-evolutionary arms race between insects and plants and to co-diversification. Anti-herbivore defences also negatively impact mutualistic partners, possibly leading to an ecological cost of toxin production. However, in other cases toxins can also be used by plants involved in mutualistic interactions to exclude inadequate partners and to modify the cost/benefit ratio of mutualism to their advantage. When considering the whole community, toxins have an effect at many trophic levels. Aposematic insects sequester toxins to defend themselves against predators. Depending on the ecological context, toxins can either increase insects’ vulnerability to parasitoids and entomopathogens or protect them, eventually leading to self-medication. We conclude that studying the community-level impacts of plant toxins can provide new insights into the synthesis between community and evolutionary ecology.
Bacteriophages with the Ability to Degrade Uropathogenic Escherichia Coli Biofilms
Authors: Chibeu Andrew , Lingohr Erika J. , Masson Luke , Manges Amee , Harel Josée , Ackermann Hans-W. , Kropinski Andrew M. , Boerlin Patrick
Published: April 2012

Escherichia coli-associated urinary tract infections (UTIs) are among the most common bacterial infections in humans. UTIs are usually managed with antibiotic therapy, but over the years, antibiotic-resistant strains of uropathogenic E. coli (UPEC) have emerged. The formation of biofilms further complicates the treatment of these infections by making them resistant to killing by the host immune system as well as by antibiotics. This has encouraged research into therapy using bacteriophages (phages) as a supplement or substitute for antibiotics. In this study we characterized 253 UPEC in terms of their biofilm-forming capabilities, serotype, and antimicrobial resistance. Three phages were then isolated (vB_EcoP_ACG-C91, vB_EcoM_ACG-C40 and vB_EcoS_ACG-M12) which were able to lyse 80.5% of a subset (42) of the UPEC strains able to form biofilms. Correlation was established between phage sensitivity and specific serotypes of the UPEC strains. The phages’ genome sequences were determined and resulted in classification of vB_EcoP_ACG-C91 as a SP6likevirus, vB_EcoM_ACG-C40 as a T4likevirus and vB_EcoS_ACG-M12 as T1likevirus. We assessed the ability of the three phages to eradicate the established biofilm of one of the UPEC strains used in the study. All phages significantly reduced the biofilm within 2–12 h of incubation.
Climate Change Adaptation and Vulnerability Assessment of Water Resources Systems in Developing Countries: A Generalized Framework and a Feasibility Study in Bangladesh
Authors: Gain Animesh K. , Giupponi Carlo , Renaud Fabrice G.
Published: April 2012

Water is the primary medium through which climate change influences the Earth’s ecosystems and therefore people’s livelihoods and wellbeing. Besides climatic change, current demographic trends, economic development and related land use changes have direct impact on increasing demand for freshwater resources. Taken together, the net effect of these supply and demand changes is affecting the vulnerability of water resources. The concept of ‘vulnerability’ is not straightforward as there is no universally accepted approach for assessing vulnerability. In this study, we review the evolution of approaches to vulnerability assessment related to water resources. From the current practices, we identify research gaps, and approaches to overcome these gaps a generalized assessment framework is developed. A feasibility study is then presented in the context of the Lower Brahmaputra River Basin (LBRB). The results of the feasibility study identify the current main constraints (e.g., lack of institutional coordination) and opportunities (e.g., adaptation) of LBRB. The results of this study can be helpful for innovative research and management initiatives and the described framework can be widely used as a guideline for the vulnerability assessment of water resources systems, particularly in developing countries.
A Personalized Approach to Treatment: Use of egfr Tyrosine Kinase Inhibitors for the Treatment of Non-Small-Cell Lung Cancer in Canada
Authors: Hirsh V. , Melosky B. , Goss G. , Morris D. , Morzycki W.
Published: April 2012

Lung cancer is one of the most commonly diagnosed malignancies and the leading cause of cancer-related mortality in Canada. The heterogeneity of nsclc and the importance of linking new targeted agents to the appropriate disease subtype require an individualized approach to treatment. In patients with EGFR (epidermal growth factor receptor gene) mutations, egfr tyrosine kinase inhibitors (tkis) provide a highly effective treatment option, with improved toxicity compared with standard chemotherapy. However, the identification of mutation-positive patients is limited by a lack of funding for testing. The length of time required to receive test results and insufficient tissue from biopsies are additional limitations. In Canada, the use of egfr-tkis varies based on differences in provincial funding for both testing and treatment. With improvements in testing and access to funding for treatment, targeted use of egfr-tkis may greatly improve outcomes in nsclc.
Disappearing Breast Cancers
Authors: Narod S.A.
Published: April 2012

Epidemiologic observations in two fields of study lead to the same conclusion: namely, that a proportion of breast cancers will go away without medical or surgical intervention[...].
Improving Cancer Control in Canada through Knowledge Translation: From in-The-Field Projects toPolicy Initiatives in a New Standing Section in Current Oncology
Authors: O’Brien M.A. , Grunfeld E.
Published: April 2012

In 2011, Current Oncology launched a new standing section, Knowledge Translation, to improve cancer control in Canada 1[...].
Selected Abstracts Submitted to the Fourth International Symposium on Hereditary Breast and Ovarian Cancer
Authors: van Asperen Christi J. , Hofland Nandy , Moghadasi Sethareh , Wouts Joyce , Wijnen Juul G. , Vreeswijk Maaike P.G.
Published: April 2012

Background: Nearly 15% of DNA tests for BRCA1/2 results in the identification of an unclassified variant (UV). In DNA diagnostic laboratories in The Netherlands, a 4-group classification system (class I to IV) is in use (Bell et al.). Aim of this study was to investigate whether the UVs in different classes showed a significant difference in their in silico characteristics and would justify current differences in protocols for counselling with respect to communication to the counselees. Methods: Missense UVs in BRCA1/2 identified between 2002 and 2010 (n = 88) were analyzed. In silico analysis of UVs was performed using SIFT– analysis Grantham score and AGVGD for the predicted severity of amino acid substitutions. Each UV was classified to one of the four classes. Results: More than half of the UVs (n = 50) were predicted to be tolerated using SIFT-analysis. Accordingly, all these variants are scored as neutral (C0) by AGVGD. Of the remaining 38 UVs not tolerated using SIFT-analysis, 19 were scored as C0 (neutral), 8 were scored C15–C25 (intermediate) and 11 were scored C35 or higher (likely to be pathogenic). Although class III UVs more frequently show in silico parameter outcomes that are suspicious for a pathogenic effect, the observed differences are not absolute. Seven UVs classified in class II had similar in silico profiles with 7 UVs in class III. Conclusion: This study showed that, in general, in silico analysis is consistently applied and proved to be able to discriminate between the different classes of UVs. However, additional analyses will be required to classify the UVs with more accuracy. In order to reduce psychological distress in families in which a UV is identified, we propose that communication of a UV should not primarily depend on its class, but also on the possibility to perform additional research in the family.
Alternative and Orthodox Medicine and the “ODD” Principle
Authors: Touyz Louis Z.G.
Published: April 2012

Although orthodox medicine trains general medical practitioners to comprehensively treat the whole patient and to refer to specialists only when patients present ailments exceeding the knowledge and skills of the practitioner, specialists continually face challenges in ensuring that their specialty careers are mutually interdependent and intertwined with total patient care. [...]