bluuebunny/crossref_metadata_2025 huggingface dataset:
Single‐layered multi‐color electrowetting display by using ink‐jet‐printing technology and fluid‐motion prediction with simulation
Authors: Ku Yun‐Sheng , Kuo Shu‐Wei , Huang Yu‐Sheng , Chen Ching‐Yao , Lo Kuo‐Long , Cheng Wei‐Yuan , Shiu Jyh‐Wen
Published: June 2011

Abstract— This paper describes a single‐layered multi‐color electrowetting display (EWD) by using ink‐jet‐printing (IJP) technology and comparing different pattern electrodes with the use of the numerical investigations of ANSYS FLUENT®. This work consists of two parts: the first describes the design of implementing a single‐layered multi‐color EWD and the second demonstrates the application of ANSYS FLUENT® simulation in different pattern electrodes settings on the proposed EWD. The single‐layered multi‐color EW device was evaluated by using various colored oils without adopting a color filter. The single‐layered multi‐color EWD at a driving voltage of 25 V can achieve a maximum aperture ratio and reflectivity of 80% and 38.5%, respectively. The colored saturation of R, G, B oils can increase to 50% (NTSC: 13.3–27.8%). In addition, a radiate electrode at the required viewable area condition of 85% and force 5 * Fk, which results in ink stable contraction and a shorter response time of 50% (radiate vs. square), was proposed. The experimental results and simulation demonstrate that ink‐jet‐printing (IJP) technology along with the use of radiate electrodes can result in a single‐layered multi‐color EWD with a shorter response time.
The influences of wolf predation, habitat loss, and human activity on caribou and moose in the Alberta oil sands
Authors: Wasser Samuel K , Keim Jonah L , Taper Mark L , Lele Subhash R
Published: June 2011

Woodland caribou (Rangifer tarandus caribou) and moose (Alces alces) populations in the Alberta oil sands region of western Canada are influenced by wolf (Canis lupus) predation, habitat degradation and loss, and anthropogenic activities. Trained domestic dogs were used to locate scat from caribou, moose, and wolves during winter surges in petroleum development. Evidence obtained from collected scat was then used to estimate resource selection, measure physiological stress, and provide individual genetic identification for precise mark–recapture abundance estimates of caribou, moose, and wolves. Strong impacts of human activity were indicated by changes in resource selection and in stress and nutrition hormone levels as human‐use measures were added to base resource selection models (including ecological variables, provincial highways, and pre‐existing linear features with no human activity) for caribou. Wolf predation and resource selection so heavily targeted deer (Odocoileus virginiana or O hemionus) that wolves appeared drawn away from prime caribou habitat. None of the three examined species showed a significant population change over 4 years. However, caribou population estimates were more than double those of previous approximations for this area. Our findings suggest that modifying landscape‐level human‐use patterns may be more effective at managing this ecosystem than intentional removal of wolves.
Linking models with monitoring data for assessing performance of no‐take marine reserves
Authors: White J Wilson , Botsford Louis W , Baskett Marissa L , Barnett Lewis AK , Barr R Jeffrey , Hastings Alan
Published: June 2011

No‐take marine reserves are an increasingly popular conservation and management tool. Assessing reserve performance in an adaptive management framework ideally involves predicting the response of populations and communities to reserves (typically in the design process) and testing predicted outcomes against observations. Here we compare existing modeling and empirical studies on no‐take marine reserves, and provide a prospectus for their future integration. Numerical models of ecological responses to reserves typically project long‐term, steady‐state interactions over the relatively broad spatial scales of larval dispersal, reserve configuration, fishing effort, and fish movement. Existing empirical studies focus on short‐term outcomes over small scales, typically aggregated over many explanatory factors. Linking models and empirical data together for the adaptive management of marine reserves requires adjusting the spatial and temporal scales of models to match empirically feasible tests, and adjusting the metrics and scale of empirical studies to account for the interacting biological and human factors affecting reserve outcomes.
Microcomputed Tomographic and Histologic Analysis of Animal Experimental Degree II Furcation Defects Treated With Porous Titanium Granules or Deproteinized Bovine Bone
Authors: Wohlfahrt Johan C. , Aass Anne M. , Rønold Hans J. , Heijl Lars , Haugen Håvard J. , Lyngstadaas Ståle P.
Published: June 2011

Background: Titanium is an interesting material for osseous reconstruction given its thrombogenic properties. The aim of this study is to compare the potential of porous titanium granules (PTGs) with sham and deproteinized bovine bone mineral (DBBM) in the reconstructive treatment of surgically created buccal, degree II furcation defects in mini‐pigs.

Methods: Buccal degree II furcation defects were surgically created in maxillary premolar teeth in adult, female, mini‐pigs and filled with PTG or DBBM or were left empty (sham). After 6 weeks of healing, pigs were euthanized. Teeth with defects were excised en bloc and analyzed by microcomputed tomography (microCT) and histology.

Results: The histologic analysis showed significantly more vertical bone formation in both PTG and sham groups compared to DBBM‐treated defects (P <0.01). The microCT analysis showed significantly more bucco‐palatal bone formation in furcations treated with PTG compared to the DBBM and sham (P <0.05). Bucco‐palatal cylindrical microCT cores demonstrated a median defect fill of 96.8% for PTG‐implanted defects, which was significantly greater than sham (72.2%) and DBBM (62.0%) (P <0.001) treatments. Significantly more regenerated periodontal ligament was seen for sham than DBBM‐treated defects (P <0.05). Root resorption lacunae were small and infrequent and did not differ among groups.

Conclusions: The results of this study in mini‐pigs suggest that PTG may integrate well in alveolar bone and supports osseous regrowth in degree II furcation defects. Moreover, PTG seems safe to use in close proximity to root surfaces. Clinical studies will be necessary to further explore these experimental animal findings.
Histologic Comparison of Healing After Ridge Preservation Using Human Demineralized Bone Matrix Putty With One Versus Two Different‐Sized Bone Particles
Authors: Hoang Tram N. , Mealey Brian L.
Published: June 2011

Background: Ridge preservation can minimize the loss of alveolar bone subsequent to tooth extraction in preparation for implant therapy. The purpose of this study is to histologically and clinically compare human demineralized bone matrix (DBM) putty with one size of bone particles (SPS) to human DBM putty with two different sizes of bone particles (multiple particle sizes [MPS]) in ridge preservation after molar extractions.

Methods: Molar tooth extraction and ridge preservation were performed in 20 participants for each treatment group. Approximately 20 weeks after grafting, core biopsies were obtained during implant placement and analyzed under light microscopy. Specimens were analyzed for the percentage area of vital bone, residual graft particles, and non‐mineralized structures (connective tissue/other non‐mineralized tissue [CT]). Changes in alveolar ridge dimensions were also determined.

Results: Sixteen participants in the SPS group and 14 in the MPS group completed the study. The SPS group had a mean of 49% vital bone, 8% residual graft, and 43% CT. The MPS group had 53%, 5%, and 42%, respectively. Patients in both groups lost a mean of <1 mm alveolar height on the buccal and lingual aspects and <1.5 mm of total ridge width. There were no statistically significant differences between the two groups for any clinical or histologic parameters.

Conclusion: The results of this study suggest that addition of larger bone particles to DBM putty does not offer additional benefit in the preservation of alveolar bone after the extraction of molar teeth.
Numerical Modeling of Multistranded-Hydraulic-Fracture Propagation: Accounting for the Interaction Between Induced and Natural Fractures
Authors: Dahi-Taleghani Arash , Olson Jon E.
Published: June 2011

Recent examples of hydraulic-fracture diagnostic data suggest that complex, multistranded hydraulic-fracture geometry is a common occurrence. This reality is in stark contrast to the industry-standard design models based on the assumption of symmetric, planar, biwing geometry. The interaction between pre-existing natural fractures and the advancing hydraulic fracture is a key condition leading to complex fracture patterns. Performing hydraulic-fracture-design calculations under these less-than-ideal conditions requires modeling fracture intersections and tracking fluid fronts in the network of reactivated fissures. Whether a hydraulic fracture crosses or is arrested by a pre-existing natural fracture is controlled by shear strength and potential slippage at the fracture intersections, as well as potential debonding of sealed cracks in the near-tip region of a propagating hydraulic fracture. We present a complex hydraulic-fracture pattern propagation model based on the extended finite-element method (XFEM) as a design tool that can be used to optimize treatment parameters under complex propagation conditions. Results demonstrate that fracture-pattern complexity is strongly controlled by the magnitude of anisotropy of in-situ stresses, rock toughness, and natural-fracture cement strength, as well as the orientation of the natural fractures relative to the hydraulic fracture. Analysis shows that the growing hydraulic fracture may exert enough tensile and shear stresses on cemented natural fractures that the latter may be debonded, opened, and/or sheared in advance of hydraulic-fracture-tip arrival, while under other conditions, natural fractures will be unaffected by the hydraulic fracture. Detailed aperture distributions at the intersection between fracture segments show the potential for difficulty in proppant transport under complex fracture-propagation conditions.
Metal Partitioning in Ilmenite- and Barite-Based Drill Cuttings on Seabed Sections in a Mesocosm Laboratory
Authors: Schaanning Morten Thorne , Trannum Hilde Cecilie , Pinturier Laurence , Rye Henrik
Published: June 2011

Ilmenite and barite minerals are alternative weight materials frequently used in drilling muds and are discharged to the marine environment. These minerals contain heavy metals that may become remobilized and available for uptake in biota after deposition in sediment. Several oil companies have jointly developed a model to predict the environmental risks associated with discharges of drill cuttings and mud to sea (DREAM). This model applies partition coefficients (Kd) for estimating heavy-metal concentrations in sediment and interstitial waters from which toxic impacts are derived. Kd depend on properties of both the particulate phase and the solute and consequently on local environmental conditions such as redox potential and pH. The literature displays Kd values ranging over several orders of magnitude, and it is a challenge and a major environmental issue to determine the most representative Kd values for drilling discharges in marine offshore areas.

An experiment was performed in box-core samples transferred from a fjord location to a marine soft-bottom mesocosm. Weight minerals and cuttings sampled from offshore drilling operations were added in thin layers on top of the fjord sediment in each box. During the next 3 months, the added layers were reworked by the naturally occurring benthic fauna. Environmental parameters such as dissolved oxygen, hydrogen sulfide, and redox potentials were determined as well as metals in added solids, sediments, interstitial water, and fluxes across the sediment/ water interface.

Kd values were obtained for seven metals. To the extent that the experimental environment was able to mimic the offshore environment with respect to bioturbation and physicochemical gradients within the sediment surface, the Kd values obtained are considered relevant for modeling interstitial-water concentrations and toxicity in offshore cuttings deposits.
Optimization and Partial Characterization of Biosurfactants Produced by Bacillus Species and Their Potential for Ex-Situ Enhanced Oil Recovery
Authors: Al-Sulaimani H.. , Al-Wahaibi Y.. , Al-Bahry S.. , Elshafie A.. , Al-Bemani A.. , Joshi S.. , Zargari S..
Published: June 2011

This study aims to test the potential of microbial enhanced oil recovery (MEOR) as an effective alternative in Omani oil fields. In this study, biosurfactants produced by Bacillus licheniformis and Bacillus subtilis strains isolated from oil-contaminated soils from different parts of the Sultanate of Oman were investigated. Eight different minimal production media using different sugars as carbon sources were tested on three of the strains to select the medium that maximized the production of biosurfactants which were indicated by the interfacial tension (IFT) reduction. All isolates were tested on their potential media to screen for the best biosurfactant producer among the available strains. It was found that Bacillus subtilis Strain W19 gave the maximum IFT reduction (46.6 mN/m to 3.28 mN/m) in 16 hours of incubation when grown in a minimal medium containing glucose. The yield of the biosurfactant produced by B. subtilis W19 was 2.5g/L. Critical micelle concentration (CMC) was measured to be 0.4 g/L. The biosurfactant was partially characterized by FT-IR analysis, in which the peaks obtained imply the presence of aliphatic hydrocarbons as well as a peptide-like moiety in the biosurfactant.

The cell-free biosurfactant broth produced from Strain W19 was found to be stable over a pH range from 6 to 10 and was most effective at 7. It also showed no loss in surface activity when subjected to various temperatures (60, 80, and 120°C). The biosurfactant also retained almost 60% of its activity even in a high-saline environment up to 20% NaCl (w/v).

Further studies were conducted to test the interaction of biosurfactant produced by B. subtilis W19 with porous media in coreflooding experiments as a tertiary-recovery stage. The results showed high potential of using this bacterium during ex-situ MEOR applications in which a total of 23% of residual oil was produced after biosurfactant and concentrated-biosurfactant injection.
Optimization of Production Performance With ICVs by Using Temperature-Data Feedback in Horizontal Wells
Authors: Li Zhuoyi , Zhu Ding
Published: June 2011

Horizontal wells with intelligent completions have been used widely in many field cases. With inflow-control valves (ICVs), production can be optimized either on individual wells or at large reservoir scale. A critical step in this procedure is to understand the inflow profiles along horizontal wellbores. To develop control and optimization strategies, permanent monitoring systems such as pressure gauges and temperature sensors have been deployed with downhole control valves to provide temperature or pressure data in real time, and to translate downhole-flow conditions from these data.

The relationships between temperature and inflow distribution have been developed before in intelligent-well models, and these models are very useful in locating water or gas entries and obtaining better production performances. In this work, we present a new idea—using temperature feedback to directly regulate flow-control valves to achieve an approximately uniform flow distribution. Instead of detecting water or gas flow with different thermal properties of fluids, we aim to regulate flow distribution through temperature behavior to achieve optimal flow conditions. Early-time temperature and pressure data are used to estimate permeability and initial flow profiles along the well; then, developed models are applied to generate a desired temperature profile that yields an evenly distributed flow rate along the wellbore. ICVs are operated on the basis of the guidance from the initial temperature data, and the temperature is monitored as it approaches the desired temperature profile. Through this procedure, we will produce a well at an optimal condition by choking down the flow rate at higher-permeability locations along the well. This can increase oil-flow rate and delay early water breakthrough.

This paper explains the details of the procedure. Two examples are used to illustrate the application of the method; one is for a waterdrive reservoir, and the other is a water-injection case. The results show significant improvement in well performance in both examples.
Extension of Das and Butler Semianalytical Flow Model
Authors: Knorr Kelvin D. , Imran Muhammad
Published: June 2011

In this work, the Das and Butler flow model was extended to account for the effect of differential pressure across a laterally and vertically spaced horizontal injection- and production-well pair for solvent vapour extraction (SVX) processes. The extended model provides a more-rigorous dispersion-coefficient correlation using interstitial pore velocity and mean particle size. This was used to history match oil-production data from 3D-scaled physical model experiments and to determine the effective dispersion coefficient of the solvent in heavy oil. The SVX experiments were performed with two model sizes and three different permeabilities spanning than two orders of magnitude. Laterally spaced horizontal wells were used to inject an 86:14 mol% mixture of butane and methane, respectively, as a dense vapour. The average dispersion coefficient of solvent (butane) was found to decrease with injected cumulative solvent and increase with reduction in permeability, and both of these relationships could be approximated with an inverse power function.
Call-Level Performance Analysis of a Power Line Communication Network Under Disturbance
Authors: Tang Shensheng , Xie Yi
Published: June 2011

Power line communication (PLC) is a promising technique for information transmission using existing power lines. We analytically model a finite-source PLC network subject to channel noise (disturbance) and evaluate its call-level performance through a queueing theoretic framework. The proposed PLC network model consists of a base station (BS), which is located at a transformer station and connected to the backbone communication networks, and a number of subscriber stations that are interconnected with each other and with the BS via the power line transmission medium. An orthogonal frequency division multiplexing based transmission technique is assumed to be used for providing the transmission channels in a frequency spectrum. The channels are subject to failure during service due to disturbance. We determine the steady-state solution of the proposed model and derive a set of performance metrics of interest. Numerical and simulation results are presented to show the derived metrics with respect to different system parameters. The proposed modeling method can be used for evaluation and design of future PLC networks.
Conserving threatened plants of Bangladesh: Miles to go before we start?
Authors: Irfanullah Haseeb Md
Published: June 2011

In the light of important developments in biodiversity conservation in the global and national arenas over the last decade (2001-2010), this paper appraises the progress in identifying threatened vascular plant species of Bangladesh as a primary step of species diversity conservation. It is argued that, as per the IUCN Red List categories and the Volume 1 of ‘Red Data Book of Vascular Plants of Bangladesh’ published in 2001, only four angiosperm species are threatened (1 Critically Endangered (CR), 1 Endangered (EN), 2 Vulnerable (VU)) in Bangladesh, not 106 vascular species. This account also records that, accordingly to the ‘Encyclopedia of Flora and Fauna of Bangladesh’ (2007-2009; Volumes 5-12), 36 pteridophyte species (all VU; 18.46% of 195 recorded species), 1 gymnosperm species (EN; 14.29% of 7 species), and 449 angiosperm species (30 CR, 126 EN, 293 VU; 12.43% of 3,611 recorded species) are threatened in the country. The paper discusses and explores the importance, limitations and opportunities for red listing of threatened plants of Bangladesh. This account further advocates for a well-planned initiative to effectively complete the Red List of threatened plant species of the country by considering appropriate, established, updated assessment methods; following collaborative approach; and capitalizing on the progress made so far. Such steps may subsequently contribute to the species diversity conservation endeavours in Bangladesh.Keywords: Angiosperm; Biodiversity; Convention on Biological Diversity; Red Data Book; Red List; Vascular plants.DOI: 10.3329/bjpt.v18i1.7844Bangladesh J. Plant Taxon. 18(1): 81-91, 2011 (June)
Kinetic ELISA in Microfluidic Channels
Authors: Yanagisawa Naoki , Dutta Debashis
Published: June 2011

In this article, we describe the kinetic ELISA of Blue Tongue and Epizootic Hemorrhagic Disease viral antibodies in microfluidic channels by monitoring the rate of generation of the enzyme reaction product under static conditions. It has been shown that this format of the immunoassay allows very reliable quantitation of the target species using inexpensive glass microchips and a standard epifluorescence microscope system coupled to a CCD camera. For the viral antibodies assayed here, the limit of detection (LOD) for the analyte concentration in our microchips was established to be 3–5 times lower than that obtained on commercial microwell plates using a fiftieth of the sample volume and less than a third of the incubation time. Our analyses further show that when compared to the end-point ELISA format, the kinetic mode of this assay yields an improvement in the LOD by over an order of magnitude in microfluidic devices. This benefit is primarily realized as the observed variation in the background fluorescence (signal at the start of the enzyme reaction period) was significantly larger than that in the rate of signal generation upon repeating these assays in different microchannels/microchips. Because the kinetic ELISA results depend only on the latter quantity, the noise level in them was substantially lower compared to that in its end-point counterpart in which the absolute fluorescence measurements are of greater significance. While a similar benefit was also recorded through implementation of kinetic ELISAs on the microwell platform, the improvement in LOD registered in that system was not as significant as was observed in the case of microfluidic assays.
Metastasizing, Luciferase Transduced MAT‑Lu Rat Prostate Cancer Models: Follow up of Bolus and Metronomic Therapy with Doxorubicin as Model Drug
Authors: Jantscheff Peter , Esser Norbert , Geipel Andreas , Woias Peter , Ziroli Vittorio , Goldschmidtboing Frank , Massing Ulrich
Published: June 2011

The most fatal outcomes of prostate carcinoma (PCa) result from hormone-refractory variants of the tumor, especially from metastatic spread rather than from primary tumor burden. The goal of the study was to establish and apply rat MAT-Lu prostate cancer tumor models for improved non-invasive live follow up of tumor growth and metastasis by in vivo bioluminescence. We established luciferase transduced MAT-Lu rat PCa cells and studied tumor growth and metastatic processes in an ectopic as well as orthotopic setting. An intravenous bolus treatment with doxorubicin was used to demonstrate the basic applicability of in vivo imaging to follow up therapeutic intervention in these models. In vitro analysis of tissue homogenates confirmed major metastatic spread of subcutaneous tumors into the lung. Our sensitive method, however, for the first time detects metastasis also in lymph node (11/24), spleen (3/24), kidney (4/24), liver (5/24), and bone tissue (femur or spinal cord - 5/20 and 12/20, respectively). Preliminary data of orthotopic implantation (three animals) showed metastatic invasion to investigated organs in all animals but with varying preference (e.g., to lymph nodes). Intravenous bolus treatment of MAT-Lu PCa with doxorubicin reduced subcutaneous tumor growth by about 50% and the number of animals affected by metastatic lesions in lymph nodes (0/4), lung (3/6) or lumbar spine (0/2), as determined by in vivo imaging and in vitro analysis. Additionally, the possible applicability of the luciferase transduced MAT-Lu model(s) to study basic principles of metronomic therapies via jugular vein catheter, using newly established active microport pumping systems, is presented.
Clinical Trial Design for Testing the Stem Cell Model for the Prevention and Treatment of Cancer
Authors: Reddy Rishindra M. , Kakarala Madhuri , Wicha Max S.
Published: June 2011

The cancer stem cell model introduces new strategies for the prevention and treatment of cancers. In cancers that appear to follow the stem cell model, pathways such as Wnt, Notch and Hedgehog may be targeted with natural compounds such as curcumin or drugs to reduce the risk of initiation of new tumors. Disease progression of established tumors could also potentially be inhibited by targeting the tumorigenic stem cells alone, rather than aiming to reduce overall tumor size. These new approaches mandate a change in the design of clinical trials and biomarkers chosen for efficacy assessment for preventative, neoadjuvant, adjuvant, and palliative treatments. Cancer treatments could be evaluated by assessing stem cell markers before and after treatment. Targeted stem cell specific treatment of cancers may not result in “complete” or “partial” responses radiologically, as stem cell targeting may not reduce the tumor bulk, but eliminate further tumorigenic potential. These changes are discussed using breast, pancreatic, and lung cancer as examples.
TRAF4, at the Crossroad between Morphogenesis and Cancer
Authors: Rousseau Adrien , Rio Marie-Christine , Alpy Fabien
Published: June 2011

Tumor Necrosis Factor Receptor-Associated Factor 4 (TRAF4) is a gene whose expression is altered in cancers. It is overexpressed in a variety of carcinomas of different origins, often as a consequence of amplification. TRAF4 encodes an adaptor protein that belongs to the TRAF protein family. While most TRAF proteins influence immune and inflammation processes, TRAF4 is mainly involved in developmental and morphogenic processes. Interestingly, this protein has been shown to be linked to crucial cellular functions such as cell polarity and the regulation of reactive oxygen species production.
On the Thermodynamics of Classical Micro-Canonical Systems
Authors: Baeten Maarten , Naudts Jan
Published: June 2011

We give two arguments why the thermodynamic entropy of non-extensive systems involves R´enyi’s entropy function rather than that of Tsallis. The first argument is that the temperature of the configurational subsystem of a mono-atomic gas is equal to that of the kinetic subsystem. The second argument is that the instability of the pendulum, which occurs for energies close to the rotation threshold, is correctly reproduced.
Exposure to Multiple Pesticides and Risk of Non-Hodgkin Lymphoma in Men from Six Canadian Provinces
Authors: Hohenadel Karin , Harris Shelley A. , McLaughlin John R. , Spinelli John J. , Pahwa Punam , Dosman James A. , Demers Paul A. , Blair Aaron
Published: June 2011

Non-Hodgkin lymphoma (NHL) has been linked to several agricultural exposures, including some commonly used pesticides. Although there is a significant body of literature examining the effects of exposure to individual pesticides on NHL, the impact of exposure to multiple pesticides or specific pesticide combinations has not been explored in depth. Data from a six-province Canadian case-control study conducted between 1991 and 1994 were analyzed to investigate the relationship between NHL, the total number of pesticides used and some common pesticide combinations. Cases (n = 513) were identified through hospital records and provincial cancer registries and controls (n = 1,506), frequency matched to cases by age and province of residence, were obtained through provincial health records, telephone listings, or voter lists. In multiple logistic regression analyses, risk of NHL increased with the number of pesticides used. Similar results were obtained in analyses restricted to herbicides, insecticides and several pesticide classes. Odds ratios increased further when only ‘potentially carcinogenic’ pesticides were considered (OR[one pesticide] = 1.30, 95% CI = 0.90–1.88; OR[two to four] = 1.54, CI = 1.11–2.12; OR[five or more] = 1.94, CI = 1.17–3.23). Elevated risks were also found among those reporting use of malathion in combination with several other pesticides. These analyses support and extend previous findings that the risk of NHL increases with the number of pesticides used and some pesticide combinations.
In Vivo Corrosion of Two Novel Magnesium Alloys ZEK100 and AX30 and Their Mechanical Suitability as Biodegradable Implants
Authors: Huehnerschulte Tim Andreas , Angrisani Nina , Rittershaus Dina , Bormann Dirk , Windhagen Henning , Meyer-Lindenberg Andrea
Published: June 2011

In magnesium alloys, the components used modify the alloy properties. For magnesium implants in contact with bone, rare earths alloys are commonly examined. These were shown to have a higher corrosion resistance than other alloys and a high mechanical strength, but their exact composition is hard to predict. Therefore a reduction of their content could be favorable. The alloys ZEK100 and AX30 have a reduced content or contain no rare earths at all. The aim of the study was to investigate their in vivo degradation and to assess the suitability of the in vivo µCT for the examination of their corrosion. Implants were inserted in rabbit tibiae. Clinical examinations, X-rays and in vivo µCT scans were done regularly. Afterwards implants were analyzed with REM, electron dispersive X-ray (EDX), weighing and mechanical testing. The in vivo µCT is of great advantage, because it allows a quantification of the corrosion rate and qualitative 3D assessment of the corrosion morphology. The location of the implant has a remarkable effect on the corrosion rate. Due to its mechanical characteristics and its corrosion behavior, ZEK100 was judged to be suitable, while AX30, which displays favorable degradation behavior, has too little mechanical strength for applications in weight bearing bones.
Delocalization of Electrons in Strong Insulators at High Dynamic Pressures
Authors: Nellis William J.
Published: June 2011

Systematics of material responses to shock flows at high dynamic pressures are discussed. Dissipation in shock flows drives structural and electronic transitions or crossovers, such as used to synthesize metallic liquid hydrogen and most probably Al2O3 metallic glass. The term “metal” here means electrical conduction in a degenerate system, which occurs by band overlap in degenerate condensed matter, rather than by thermal ionization in a non-degenerate plasma. Since H2 and probably disordered Al2O3 become poor metals with minimum metallic conductivity (MMC) virtually all insulators with intermediate strengths do so as well under dynamic compression. That is, the magnitude of strength determines the split between thermal energy and disorder, which determines material response. These crossovers occur via a transition from insulators with electrons localized in chemical bonds to poor metals with electron energy bands. For example, radial extents of outermost electrons of Al and O atoms are 7 a0 and 4 a0, respectively, much greater than 1.7 a0 needed for onset of hybridization at 300 GPa. All such insulators are Mott insulators, provided the term “correlated electrons” includes chemical bonds.
Cholesterol-Lowering Activity of the Major Polyphenols in Grape Seed
Authors: Ngamukote Sathaporn , Mäkynen Kittana , Thilawech Thavaree , Adisakwattana Sirichai
Published: June 2011

The major polyphenols in grape seed have been shown to have beneficial health effects in the prevention of dyslipidemia and cardiovascular diseases. In this present study, we investigated the cholesterol-lowering activity of three major polyphenolic compounds found in grape seed. The results showed that gallic acid, catechin, and epicatechin significantly inhibited pancreatic cholesterol esterase in a concentration-dependent manner. Moreover, they bound to taurocholic acid, taurodeoxycholic acid, and glycodeoxycholic acid at levels ranging from 38.6% to 28.2%. At the concentration of 0.2 mg/mL, gallic acid, catechin, and epicatechin reduced the formation of cholesterol micelles 27.26 ± 2.17%, 11.88 ± 0.75%, and 19.49 ± 3.71%, respectively. These findings clearly demonstrate that three major polyphenolic compounds present in a particular grape seed have cholesterol-lowering activity by inhibiting pancreatic cholesterol esterase, binding of bile acids, and reducing solubility of cholesterol in micelles which may result in delayed cholesterol absorption.
Crystallization and Characterization of an Inflammatory Lectin Purified from the Seeds of Dioclea wilsonii
Authors: Rangel Thaiz Batista Azevedo , Assreuy Ana Maria Sampaio , Pires Alana de Freitas , Carvalho Amanda Uliana de , Benevides Raquel Guimarães , Simões Rafael da Conceição , Silva Helton Colares da , Bezerra Maria Júlia Barbosa , Nascimento Antonia Samia Fernandes do , Nascimento Kyria Santiago do , Nagano Celso Shiniti , Sampaio Alexandre Holanda , Delatorre Plínio , Rocha Bruno Anderson Matias da , Fernandes Patricia Machado Bueno , Cavada Benildo Sousa
Published: June 2011

DwL, a lectin extracted from the seeds of Dioclea wilsonii, is a metalloprotein with strong agglutinating activity against rabbit and ABO erythrocytes, inhibited by glucose and mannose. DwL was purified by affinity chromatography on a Sephadex G-50 column and ion exchange chromatography on a HiTrap SP XL column. SDS-PAGE revealed three electrophoretic bands corresponding to the α (25,634 ± 2 Da), β (12,873 ± 2 Da) and γ (12,779 ± 2 Da) chains. Protein sequencing was done by Tandem Mass Spectrometry. The primary sequence featured 237 amino acids and was highly homologous to other reported Diocleinae lectins. A complete X-ray dataset was collected at 2.0 Å for X-Man-complexed DWL crystals produced by the vapor diffusion method. The crystals were orthorhombic and belonged to the space group I222, with the unit-cell parameters a = 59.6, b = 67.9 and c = 109.0 Å. DWL differed in potency from other ConA-like lectins and was found to induce neutrophil migration in rats, making it particularly useful in structural/functional studies of this class of proteins.
Methoxymethyl (MOM) Group Nitrogen Protection of Pyrimidines Bearing C-6 Acyclic Side-Chains
Authors: Kraljević Tatjana Gazivoda , Petrović Martina , Krištafor Svjetlana , Makuc Damjan , Plavec Janez , Ross Tobias L. , Ametamey Simon M. , Raić-Malić Silvana
Published: June 2011

Novel N-methoxymethylated (MOM) pyrimidine (4-13) and pyrimidine-2,4-diones (15-17) nucleoside mimetics in which an isobutyl side-chain is attached at the C-6 position of the pyrimidine moiety were synthesized. Synthetic methods via O-persilylated or N-anionic uracil derivatives have been evaluated for the synthesis of N-1- and/or N-3-MOM pyrimidine derivatives with C-6 acyclic side-chains. A synthetic approach using an activated N-anionic pyrimidine derivative afforded the desired N,N-1,3-diMOM and N-1-MOM pyrimidines 4 and 5 in good yield. Introduction of fluorine into the side-chain was performed with DAST as the fluorinating reagent to give a N,N-1,3-diMOM pyrimidine 13 with a 1-fluoro-3-hydroxyisobutyl moiety at C-6. Conformational study of the monotritylated N-1-MOM pyrimidine 12 by the use of the NOE experiments revealed the predominant conformation of the compound to be one where the hydroxymethyl group in the C-6 side-chain is close to the N-1-MOM moiety, while the OMTr is in proximity to the CH3-5 group. Contrary to this no NOE enhancements between the N-1-MOM group and hydroxymethyl or fluoromethyl protons in 13 were observed, which suggested a nonrestricted rotation along the C-6 side-chain. Fluorinated N,N-1,3-diMOM pyrimidine 13 emerged as a model compound for development of tracer molecules for non-invasive imaging of gene expression using positron emission tomography (PET).
Regeneration of Hair Cells: Making Sense of All the Noise
Authors: Kopecky Benjamin , Fritzsch Bernd
Published: June 2011

Hearing loss affects hundreds of millions of people worldwide by dampening or cutting off their auditory connection to the world. Current treatments for sensorineural hearing loss (SNHL) with cochlear implants are not perfect, leaving regenerative medicine as the logical avenue to a perfect cure. Multiple routes to regeneration of damaged hair cells have been proposed and are actively pursued. Each route not only requires a keen understanding of the molecular basis of ear development but also faces the practical limitations of stem cell regulation in the delicate inner ear where topology of cell distribution is essential. Improvements in our molecular understanding of the minimal essential genes necessary for hair cell formation and recent advances in stem cell manipulation, such as seen with inducible pluripotent stem cells (iPSCs) and epidermal neural crest stem cells (EPI-NCSCs), have opened new possibilities to advance research in translational stem cell therapies for individuals with hearing loss. Despite this, more detailed network maps of gene expression are needed, including an appreciation for the roles of microRNAs (miRs), key regulators of transcriptional gene networks. To harness the true potential of stem cells for hair cell regeneration, basic science and clinical medicine must work together to expedite the transition from bench to bedside by elucidating the full mechanisms of inner ear hair cell development, including a focus on the role of miRs, and adapting this knowledge safely and efficiently to stem cell technologies.
In Vitro Dissolution Methods for Hydrophilic and Hydrophobic Porous Silicon Microparticles
Authors: Mönkäre Juha , Riikonen Joakim , Rauma Elina , Salonen Jarno , Lehto Vesa-Pekka , Järvinen Kristiina
Published: June 2011

Porous silicon (PSi) is an innovative inorganic material that has been recently developed for various drug delivery systems. For example, hydrophilic and hydrophobic PSi microparticles have been utilized to improve the dissolution rate of poorly soluble drugs and to sustain peptide delivery. Previously, the well-plate method has been demonstrated to be a suitable in vitro dissolution method for hydrophilic PSi particles but it was not applicable to poorly wetting hydrophobic thermally hydrocarbonized PSi (THCPSi) particles. In this work, three different in vitro dissolution techniques, namely centrifuge, USP Apparatus 1 (basket) and well-plate methods were compared by using hydrophilic thermally carbonized PSi (TCPSi) microparticles loaded with poorly soluble ibuprofen or freely soluble antipyrine. All the methods showed a fast and complete or nearly complete release of both model compounds from the TCPSi microparticles indicating that all methods described in vitro dissolution equally. Based on these results, the centrifuge method was chosen to study the release of a peptide (ghrelin antagonist) from the THCPSi microparticles since it requires small sample amounts and achieves good particle suspendability. Sustained peptide release from the THCPSi microparticles was observed, which is in agreement with an earlier in vivo study. In conclusion, the centrifuge method was demonstrated to be a suitable tool for the evaluation of drug release from hydrophobic THCPSi particles, and the sustained peptide release from THCPSi microparticles was detected.
Toronto’s Urban Heat Island—Exploring the Relationship between Land Use and Surface Temperature
Authors: Rinner Claus , Hussain Mushtaq
Published: June 2011

The urban heat island effect is linked to the built environment and threatens human health during extreme heat events. In this study, we analyzed whether characteristic land uses within an urban area are associated with higher or lower surface temperatures, and whether concentrations of “hot” land uses exacerbate this relationship. Zonal statistics on a thermal remote sensing image for the City of Toronto revealed statistically significant differences between high average temperatures for commercial and resource/industrial land use (29.1 °C), and low average temperatures for parks and recreational land (25.1 °C) and water bodies (23.1 °C). Furthermore, higher concentrations of either of these land uses were associated with more extreme surface temperatures. We also present selected neighborhoods to illustrate these results. The paper concludes by recommending that municipal planners and decision-makers formulate policies and regulations that are specific to the problematic land uses, in order to mitigate extreme heat.
Low-Cost Gas Sensors Produced by the Graphite Line-Patterning Technique Applied to Monitoring Banana Ripeness
Authors: Manzoli Alexandra , Steffens Clarice , Paschoalin Rafaella T. , Correa Alessandra  A. , Alves William F. , Leite Fábio  L. , Herrmann Paulo  S. P.
Published: June 2011

A low-cost sensor array system for banana ripeness monitoring is presented. The sensors are constructed by employing a graphite line-patterning technique (LPT) to print interdigitated graphite electrodes on tracing paper and then coating the printed area with a thin film of polyaniline (PANI) by in-situ polymerization as the gas-sensitive layer. The PANI layers were used for the detection of volatile organic compounds (VOCs), including ethylene, emitted during ripening. The influence of the various acid dopants, hydrochloric acid (HCl), methanesulfonic acid (MSA), p-toluenesulfonic acid (TSA) and camphorsulfonic acid (CSA), on the electrical properties of the thin film of PANI adsorbed on the electrodes was also studied. The extent of doping of the films was investigated by UV-Vis absorption spectroscopy and tests showed that the type of dopant plays an important role in the performance of these low-cost sensors. The array of three sensors, without the PANI-HCl sensor, was able to produce a distinct pattern of signals, taken as a signature (fingerprint) that can be used to characterize bananas ripeness.
An Image Segmentation Based on a Genetic Algorithm for Determining Soil Coverage by Crop Residues
Authors: Ribeiro Angela , Ranz Juan , Burgos-Artizzu Xavier  P. , Pajares Gonzalo , Sanchez del Arco Maria  J. , Navarrete Luis
Published: June 2011

Determination of the soil coverage by crop residues after ploughing is a fundamental element of Conservation Agriculture. This paper presents the application of genetic algorithms employed during the fine tuning of the segmentation process of a digital image with the aim of automatically quantifying the residue coverage. In other words, the objective is to achieve a segmentation that would permit the discrimination of the texture of the residue so that the output of the segmentation process is a binary image in which residue zones are isolated from the rest. The RGB images used come from a sample of images in which sections of terrain were photographed with a conventional camera positioned in zenith orientation atop a tripod. The images were taken outdoors under uncontrolled lighting conditions. Up to 92% similarity was achieved between the images obtained by the segmentation process proposed in this paper and the templates made by an elaborate manual tracing process. In addition to the proposed segmentation procedure and the fine tuning procedure that was developed, a global quantification of the soil coverage by residues for the sampled area was achieved that differed by only 0.85% from the quantification obtained using template images. Moreover, the proposed method does not depend on the type of residue present in the image. The study was conducted at the experimental farm “El Encín” in Alcalá de Henares (Madrid, Spain).
T Cell Targeting by Anthrax Toxins: Two Faces of the Same Coin
Authors: Rossi Paccani Silvia , Baldari Cosima  T.
Published: June 2011

Bacillus anthracis, similar to other bacterial pathogens, has evolved effective immune evasion strategies to prolong its survival in the host, thus ensuring the unchecked spread of the infection. This function is subserved by lethal (LT) and edema (ET) toxins, two exotoxins produced by vegetative anthrax bacilli following germination of the spores. The structure of these toxins and the mechanism of cell intoxication are topics covered by other reviews in this issue. Here we shall discuss how B. anthracis uses LT and ET to suppress the immune defenses of the host, focusing on T lymphocytes, the key players in adaptive immunity. We shall also summarize recent findings showing that, depending on its concentration, ET has the ability not only to suppress T cell activation but also to promote the polarization of CD4+ T cells to the Th2 and Th17 subsets, highlighting the potential use of this toxin as an immunomodulator.
Targeting HTLV-1 Activation of NFκB in Mouse Models and ATLL Patients
Authors: Rauch Daniel A. , Ratner Lee
Published: June 2011

Of the millions of HTLV-1 infected carriers worldwide, 3–5% will develop an aggressive T-cell neoplasm that is highly refractory to conventional therapy. The virus carries the Tax oncogene which constitutively activates the NFκB pathway. This co-option of signaling through NFκB provides for the HTLV-1 infected cell an escape from cell cycle arrest and apoptosis, a steady source of growth factors, and a mechanism by which the virus can activate its own target cell. Therapies that target the NFκB pathway sensitize adult T-cell leukemia/lymphoma (ATLL) cells to apoptosis. A focus on translational interrogation of NFκB inhibitors in animal models and ATLL patients is needed to advance NFκB-targeted ATLL therapies to the bedside.
Isotopic labelling studies for a gold-catalysed skeletal rearrangement of alkynyl aziridines
Authors: Davies Paul W , Martin Nicolas , Spencer Neil
Published: June 2011

Isotopic labelling studies were performed to probe a proposed 1,2-aryl shift in the gold-catalysed cycloisomerisation of alkynyl aziridines into 2,4-disubstituted pyrroles. Two isotopomers of the expected skeletal rearrangement product were identified using 13C-labelling and led to a revised mechanism featuring two distinct skeletal rearrangements. The mechanistic proposal has been rationalised against the reaction of a range of 13C- and deuterium-labelled substrates.
Inspiration et perspectives de la révolution tunisienne
Authors: Ferjani Mohamed Chérif
Published: June 2011

Véritable catalyseur des révoltes qui traversent le monde arabe, la révolution tunisienne était peu prévisible tout comme l’est l’issue de la transition en cours. Cet article revient sur les origines du soulèvement tunisien. Il évalue également les questions qui se posent aujourd’hui au pays mais également les hypothèques politiques et économiques qui demeurent. Alors que l’espace politique s’ouvre fortement, l’auteur fait également un tour d’horizon des formations politiques engagées dans la nouvelle Tunisie, en analysant leur discours et en évaluant leur force.
L'orientalisme et les révolutions tunisienne et égyptienne : pourquoi ne l'ont-ils pas aimée la révolution ?
Authors: Ben Hammouda Hakim
Published: June 2011

Les révolutions en cours dans le monde arabe ont été à l’origine d’un important débat sur l’attitude des intellectuels occidentaux. La timidité de leurs réactions au moment des épisodes tunisien et égyptien a suscité des interrogations et des questionnements. L’objectif de cette contribution est de comprendre les raisons du peu d’empressement de ces intellectuels à apporter un franc soutien aux peuples arabes comme ils l’ont fait lors de la chute du mur de Berlin ou de la guerre dans l’ex-Yougoslavie.