bluuebunny/crossref_metadata_2025 huggingface dataset:
A Method for Predicting the Tendency of Oil Field Waters To Deposit Calcium Carbonate
Authors: Stiff Henry A. , Davis Lawrence E.
Published: April 2012

The authors previously presented a method for predicting the tendency of oilfield waters to deposit calcium sulfate. The present paper gives a similarmethod for calcium carbonate.

Methods for predicting calcium carbonate scaling tendencies in fresh watershave been available for some time, but these could not be used for brines. Byexperimentally deriving the value of the K term in the Langelier equation, amethod has been developed which applies to waters of high salt content. Astatistical study is included which shows that the experimentally derivedvalues of K are in good agreement with actual conditions. Several applicationsof the final equation to production practice are given.

Introduction

The authors previously presented a method for predicting the formation ofcalcium sulfate scale in oil field waters. Although calcium sulfate depositionis important in production operations, the majority of scale problems involvecalcium carbonate. The present communication discusses a method by which theformation of this type of scale in oil field waters can be predicted.

Calcium carbonate precipitation is caused by a shift toward carbonate in thecarbonate-bicarbonate-carbon dioxide equilibrium. When equilibrium shifts inthe other direction, the precipitate goes back into solution. Since there isusually considerable delay between the establishment of an equilibrium and theprecipitation or solution of calcium carbonate, unstable conditions exist inwhich a water will precipitate or dissolve calcium carbonate on standing.

Tillmans, who did a major part of the early work on carbonate scaling, pointed out that the condition of equilibrium not only indicates the tendencyof a water to scale but also is an indication of its corrosive properties.Previously precipitated calcium carbonate combines with iron to form a densecrust which inhibits corrosion. If the water tends to dissolve carbonate, thescale becomes porous, and electrolytic corrosion takes place. Tillmans work wasextended by several investigators until in 1934 Langelier developed an equationsetting forth the conditions of carbonate equilibrium. By the use of thisequation the pH of a water at equilibrium can be calculated. If the actual pHis higher than the calculated pH, the water has a tendency to form scale. If itis lower, the water has a tendency to be corrosive.

T.P. 3395
The Slip Velocity of Gases Rising Through Liquid Columns
Authors: Stein N. , Elfrink E.B. , Wiener L.D. , Sandberg C.R.
Published: April 2012

This paper presents the results of a study of the slip velocity of gasesrising through liquids in vertical tubes, inclined tubes, and vertical annuli.The data were obtained in gas-liquid systems which included combinations ofair, propane and natural gas (over 97 percent methane) with water, lubricatingoils, and crude oils. The 214 data points obtained in this study along with 11data points reported in the literature are incorporated in an empiricalcorrelation which relates the mean slip velocity of gases flowing throughliquids with the parameters gas rate, tube size, ratio of liquid viscosity toliquid density, gas density, liquid density, and the angle of the tube from thevertical.

The average numerical deviation of the measured slip velocity data fromvalues obtained from the correlation is 9.2 per cent. The average algebraicdeviation between measured and predicted data is 0.31 per cent, an indicationthat the correlation is a satisfactory representation of the data.

The correlation presented in this paper will be useful primarily in thedesign of subsurface gas-oil separation equipment for increasing the efficiencyof oil-well pumping installations, but may perhaps be extended to othersituations of gases rising through liquid columns.

Introduction

The production of oil by pumping is often complicated by the presence offree and dissolved gas in the oil at bottomhole conditions. This gas can bedrawn into the pump barrel and result in "vapor locking" the pump, thusreducing the efficiency of the pumping operation. Large amounts of free gas maybe excluded from the pump by the use of a gas-anchor, which is designed toallow the separation of free gas from the oil before it is drawn into the pump.The design of a suitable gas-anchor depends on a knowledge of the differencebetween the velocity of the free gas and that of the oil as the oil travelsdown toward the pump intake. This rate of gas rise through the oil is termed"slip velocity.

T.P. 3394
A Note on the X-Ray Absorption Method of Determining Fluid Saturation in Cores
Authors: Geffen T.M. , Gladfelter R.E.
Published: April 2012

Lipson has recently presented a technical note wherein theoreticalconsiderations were used to demonstrate "… that the adsorption vssaturation relation for a linear absorption method is not necessarily a singlevalued function of saturation." It was concluded that the absorption vssaturation relationship is subject to the same hysteretic effect as is the flowbehavior between the drainage and imbibition systems. It is the purpose of thisnote to show, by experimental results, that for the manner in which fluids aredistributed in porous materials during fluid flow, the relative X-rayabsorption vs saturation relationship is single-valued regardless of thesaturation history.

The design of the apparatus used to measure relative X-ray absorption ofcores undergoing fluid flow tests is similar to that described by Morgan, McDowell and Doty. A few modifications have been incorporated in the design toincrease sensitivity and simplicity of measurement. The sensitivity is suchthat for usual types of cores a recording pen movement of approximately 12linear in. is occasioned between the recording of the core dry and when it iscompletely full of an absorbing liquid, a solution of approximately five percent by volume of iodobenzene in a close-cut hydrocarbon fraction, or asolution of 50,000 ppm sodium iodide in water.

Two types of experiments were conducted, one in which the liquid was insidethe core, and the other with the liquid outside the core. Tests with the liquidinside the core were run to cover the saturation range encountered in both thedrainage (gas drive) and imbibition (liquid flood) flow systems. It is pointedout that the same core was used, but the tests were conducted at differenttimes with the recording mechanism balanced at a different position. Therefore, the absolute values of relative X-ray intensity at any saturation are not thesame in each test.

In the second type of test the same core was used, but this time its porespace contained only gas, and various thicknesses of oil contained in plasticcells were placed in front of the dry core.

T.N. 110
Description and Analysis of an Efficient Continuous-Flow Gas-Lift Installation
Authors: Bertuzzi A.F. , Welchon J.K. , Poettman F.H.
Published: April 2012

A series of gas-lift tests was made which verified conclusions reached fromprevious studies and which showed that gas-lift performance could be calculatedif reasonably accurate data on the producing characteristics of the well areavailable. The test installation is described. Its essential features consistedof a rate-of-flow controller to regulate the input gas and an auxiliary stringof small diameter tubing to conduct the input gas to the point of injection inthe eductor tubing. In general, it was shown that for continuous gas-liftoperation, injection should be as deep as possible consistent with availablegas pressure and rate of production desired. Calculated curves are presentedwhich completely characterize the gas-lift performance of the well tested.

Introduction

A correlation based on field data from a large number of flowing andgas-lift wells, covering a wide range of operating conditions, was developedwhich permitted the logical design and prediction of the performance ofcontinuous gas-lift installations. The procedure made it possible to calculatethe depth, pressure, rate at which to inject gas, horsepower requirements, andthe effect of production rate and tubing size on these quantities. As a resultof these calculations certain significant facts were brought to light orre-emphasized. The presence of efficient ranges of operation and an optimuminjection depth for a given rate of production were shown to exist as well asthe fact that the lower the tubing pressure the less the horsepowerrequirements to lift the reservoir fluids. The fact that the gas-liftperformance can be predicted by calculation does not mean that any giveninstallation will perform over the entire range predicted. Many of theconventional continuous gas-lift installations will not permit operation overthe entire range predicted by calculation (particularly in the efficient rangeof operation) because of the performance characteristics of the installation.Consequently, field tests were initiated for the purpose of investigating andarriving at a simple continuous gas-lift installation which would operate underall conditions predicted by calculation.

T.P. 3694
The Effect of Temperature on the Density and Electrical Resistivity of Sodium Chloride Solutions
Authors: Arps J.J.
Published: April 2012

This paper is a study of the effect of temperature on the electricalresistivity of sodium chloride solutions based on the published resistivity anddensity data in the International Critical Tables. This temperature effect isof considerable importance in quantitative interpretation of electric logs, where it is frequently necessary to correct mud resistivities measured undersurface conditions to temperatures existing at the bottom of the bore hole. Anempirical approximation formula was developed for this conversion which hasproved to be very useful and seems to provide results well within the range ofaccuracy of the data involved.

Introduction

Research by various investigators during the past 20 years has clarified thephysical principles of the phenomena which cause the natural or spontaneouselectric potential in rotary drilled bore holes.

In order to calculate the resistivity of the connate water Rw and toestimate its "equivalent salinity" (as NaCl) from an electric log bymeans of this SP relationship from a knowledge of the static self potential andof the resistivity of the mud filtrate Rmf, it is necessary to first correctthe resistivity of the mud filtrate measured under surface conditions to theresistivity of this same mud filtrate in the well bore at a differenttemperature.

In order to make this temperature conversion for the mud filtrate thevariation of the electrical resistivity of sodium chloride solutions withtemperature is commonly used. Since some discrepancies were found in the charts.ordinarily used for this purpose, it was felt desirable to make a new study ofthis relationship based on the published measurement data. Because of thefundamental nature of these relationships and as an aid to other workers inthis field, an attempt has been made in this study to show every step in thecalculations.

T.N. 195
A Causal Model of Hopelessness Depression in Chinese Undergraduate Students
Authors: Feng Zheng-Zhi , Yi Hong
Published: April 2012

The diathesis-stress component hypothesis and the mediational role of hopelessness proposed by the hopelessness theory of depression were tested using data from a 16-week longitudinal study of Chinese university undergraduates. Participants (N = 240) completed self-report measures
assessing attributional style, negative life events, hopelessness, and hopelessness depression symptoms at 3 time points. The diathesis-stress hypothesis was tested using the latent growth curve model and results showed that as postulated in the hopelessness theory, depressogenic attributional
style predicted hopelessness depression following the occurrence of negative life events. Specifically, hopelessness played a partial mediating role in the etiological chain of hopelessness depression.
The Sweet Smell of the Requester: Vanilla, Camphor, and Foot-in-the-Door
Authors: Saint-Bauzel Roxane , Fointiat Valérie
Published: April 2012

Several researchers have shown that odors affect human behavior. However, odors have not been studied in the context of specific compliance without pressure. Specifically, the impact of the odor worn by a requester during the foot-in-the-door procedure has not been documented. To address
this issue, an experiment was carried out in an ecological setting. Using the foot-in-the-door procedure, a well-known technique for increasing the likelihood that a person will comply with one's request, the requester was perfumed with vanilla, camphor, or nothing. The results show a strong
effect of the foot-in-the-door technique when the requester was perfumed with vanilla and no effect of the procedure when the requester was perfumed with camphor. These results are incompatible with the main theoretical interpretations of foot-in-the-door phenomena: self-perception and commitment
theories.
Rutting mechanisms and advanced laboratory testing of asphalt mixtures resistance against permanent deformation
Authors: Miljkovic Miomir , Radenberg Martin
Published: April 2012

Permanent deformation in asphalt layers which manifestation on pavement
surface is named rutting represents one of the most significant distresses of
asphalt pavements. Depending on the level, it can be a huge inconvenience for
traffic safety, driving comfort, and overall pavement life-cycle. Rutting may
be classified into three basic types: one-dimensional or vertical compaction,
lateral flow or plastic movement, and mechanical deformation. As an addition
to Superpave? mixture volumetric design three, so called, simple performance
tests (SPT) were recommended. Each of these tests in conduced in uniaxial or
triaxial compression of cylindrical specimens. They cover the determination
of dynamic modulus, repeated load permanent deformation test (flow number),
and static load permanent deformation test (flow time). These tests provide
relatively good insight in on-site mixture performance. An application of
these tests provides a potential link between mixture design and structural
analysis that was an underlying goal of substantial amount of earlier
flexible pavement researches.
The Impact of Treatment Noncompliance on Mortality in People With Type 2 Diabetes
Authors: Currie Craig J. , Peyrot Mark , Morgan Christopher Ll. , Poole Chris D. , Jenkins-Jones Sara , Rubin Richard R. , Burton Christopher M. , Evans Marc
Published: April 2012

OBJECTIVE

To assess the association of compliance with treatment (medication and clinic appointments) and all-cause mortality in people with insulin-treated type 2 diabetes.

RESEARCH DESIGN AND METHODS

Data were extracted from U.K. general practice records and included patients (N = 15,984) who had diagnostic codes indicative of type 2 diabetes or who had received a prescription for an oral antidiabetic agent and were treated with insulin. Records in the 30 months before the index date were inspected for clinical codes (recorded at consultation) indicating medication noncompliance or medical appointment nonattendance. Noncompliance was defined as missing more than one scheduled visit or having at least one provider code for not taking medications as prescribed. Relative survival postindex date was compared by determining progression to all-cause mortality using Cox proportional hazards models.

RESULTS

Those identified as clinic nonattenders were more likely to be smokers, younger, have higher HbA1c, and have more prior primary care contacts and greater morbidity (P < 0.001). Those identified as medication noncompliers were more likely to be women (P = 0.001), smokers (P = 0.014), and have higher HbA1c, more prior primary care contacts, and greater morbidity (all P < 0.001). After adjustment for confounding factors, medication noncompliance (hazard ratio 1.579 [95% CI 1.167–2.135]), clinic nonattendance of one or two missed appointments (1.163 [1.042–1.299]), and clinic nonattendance of greater than two missed appointments (1.605 [1.356–1.900]) were independent risk factors for all-cause mortality.

CONCLUSIONS

Medication noncompliance and clinic nonattendance, assessed during routine care by primary care physicians or their staff, were independently associated with increased all-cause mortality in patients with type 2 diabetes receiving insulin.
Physical and mechanical properties of hemp seed
Authors: Taheri-Garavand A. , Nassiri A. , Gharibzahedi S.
Published: April 2012

Physical and mechanical properties of hemp seed

The current study was conducted to investigate the effect of moisture content on the post-harvest physical and mechanical properties of hemp seed in the range of 5.39 to 27.12% d.b. Results showed that the effect of moisture content on the most physical properties of the grain was significant (P<0.05). The results of mechanical tests demonstrated that the effect of loading rate on the mechanical properties of hemp seed was not significant. However, the moisture content effect on rupture force and energy was significant (P<0.01). The lowest value of rupture force was obtained at the highest loading rate (3mm min-1)and in the moisture content of 27.12% d.b. Moreover, the interaction effects of loading rate and moisture content on the rupture force and energy of hemp seed were significant (P<0.05).
Cervical Disk Pathology in Patients With Multiple Sclerosis: Two Case Reports
Authors: Mullen Ann E. , Wilmarth Mary Ann , Lowe Sue
Published: April 2012

Background and Purpose

A patient with multiple sclerosis (MS) may be seen by a physical therapist for evaluation before the MS diagnosis is definitively made, after a relapse, or during a progression. The diagnosis of MS should be part of the differential diagnosis if the symptoms of a patient with neurological issues fit the pattern of a progressive disease. Multiple sclerosis can affect any part of the central nervous system. Cervical pathology can be confused with relapsing symptoms of MS. The purpose of this case report is to demonstrate how easily cervical pathology can be overlooked in a patient with MS.

Case Description

Two case reports of patients with relapsing MS are presented. Both patients were referred for physical therapy after not responding to standard treatment with intravenous methylprednisolone. One patient reported multiple falls and complained of increasing cervical pain and spasm, fatigue, bouts of diplopia, and difficulty ambulating. The other patient complained of headaches, visual disturbances, and cervical pain with radicular symptoms. Contrast magnetic resonance imaging (MRI) did not reveal new MS lesions or the extension of old MS lesions. The cervical herniations in the first patient, not previously documented, were old. The bulging disks in the second patient, seen in a previous study, were unchanged. The MRI findings did not support the diagnosis of acute inflammatory MS or acute cervical pathology.

Outcomes

Both patients responded to physical therapy intervention once the cervical symptoms were directly addressed. As the cervical pain and spasm decreased, the relapsing MS symptoms of dysmetria, balance disturbance, and ataxic gait began to diminish. In both patients, eye function was slow to recover, with persistent impairment. Both patients returned to their premorbid activity and socialization level.

Discussion

Cervical disk disease should be considered in the differential diagnosis when a patient with MS has a history of trauma and displays abnormal postures, spastic weakness, and changes in pain complaints. In these 2 cases, treating the cervical pathology in addition to the MS symptoms provided the most effective approach for functional improvement.
"What Do You Expect? That We All Dance and Be Happy?" Second-Generation Immigrants and Germany's 1999 Citizenship Reform
Authors: Bucerius Sandra
Published: April 2012

Based on a five-year ethnography, this article looks at Germany's citizenship reform of 1999 from the perspective of a population that is often at the center of attention: second generation immigrant drug dealers. While the reform had the potential to make a significant difference for this group, with respect to both their legal status in the country and perception of Germany, the findings of this article show that the reform did not have such an impact. On the contrary, the reform seems to have had the opposite effect, alienating the young men even more from Germany by keeping citizenship out of reach for them. While some have argued that in the light of supranational citizenship norms and the discourse of citizenship rights as human rights, national citizenship becomes increasingly unimportant as new forms of post-national citizenship gradually emerge, this does not seem to hold true for the young men of this study.
Characteristics of CO2 Hydrate Formation and Dissociation in Glass Beads and Silica Gel
Authors: Yang Mingjun , Song Yongchen , Ruan Xuke , Liu Yu , Zhao Jiafei , Li Qingping
Published: April 2012

CO2 hydrate formation and dissociation is crucial for hydrate-based CO2 capture and storage. Experimental and calculated phase equilibrium conditions of carbon dioxide (CO2) hydrate in porous medium were investigated in this study. Glass beads were used to form the porous medium. The experimental data were generated using a graphical method. The results indicated the decrease of pore size resulted in the increase of the equilibrium pressure of CO2 hydrate. Magnetic resonance imaging (MRI) was used to investigate the priority formation site of CO2 hydrate in different porous media, and the results showed that the hydrate form firstly in BZ-02 glass beads under the same pressure and temperature. An improved model was used to predict CO2 hydrate equilibrium conditions, and the predictions showed good agreement with experimental measurements.
Estimation of State of Charge of Lithium-Ion Batteries Used in HEV Using Robust Extended Kalman Filtering
Authors: Zhang Caiping , Jiang Jiuchun , Zhang Weige , Sharkh Suleiman M.
Published: April 2012

A robust extended Kalman filter (EKF) is proposed as a method for estimation of the state of charge (SOC) of lithium-ion batteries used in hybrid electric vehicles (HEVs). An equivalent circuit model of the battery, including its electromotive force (EMF) hysteresis characteristics and polarization characteristics is used. The effect of the robust EKF gain coefficient on SOC estimation is analyzed, and an optimized gain coefficient is determined to restrain battery terminal voltage from fluctuating. Experimental and simulation results are presented. SOC estimates using the standard EKF are compared with the proposed robust EKF algorithm to demonstrate the accuracy and precision of the latter for SOC estimation.
Bloggers’ Community Characteristics and Influence within Greek Political Blogosphere
Authors: Zafiropoulos Kostas , Vrana Vasiliki , Vagianos Dimitrios
Published: April 2012

This paper investigates the properties of central or core political blogs. They can be located as clusters of blogs whose members have many incoming links. Other blogs form clouds around them in the sense that they link the core blogs. A case study records Greek political blogs and their incoming links reported through their blogrolls. The adjacency matrix from the blogs’ social network is analyzed and clusters are located. Three of them, those with the larger numbers of incoming links, may be considered to be central. Next, four measures of influence are used to test the influence of the central blogs. The findings suggest that there are many kinds of central blogs, influential and non-influential, and high influence does not always involve high hyperlinking.
Structural Features of Caspase-Activating Complexes
Authors: Park Hyun Ho
Published: April 2012

Apoptosis, also called programmed cell death, is an orderly cellular suicide program that is critical for the development, immune regulation and homeostasis of a multi-cellular organism. Failure to control this process can lead to serious human diseases, including many types of cancer, neurodegenerative diseases, and autoimmununity. The process of apoptosis is mediated by the sequential activation of caspases, which are cysteine proteases. Initiator caspases, such as caspase-2, -8, -9, and -10, are activated by formation of caspase-activating complexes, which function as a platform to recruit caspases, providing proximity for self-activation. Well-known initiator caspase-activating complexes include (1) DISC (Death Inducing Signaling Complex), which activates caspases-8 and 10; (2) Apoptosome, which activates caspase-9; and (3) PIDDosome, which activates caspase-2. Because of the fundamental biological importance of capases, many structural and biochemical studies to understand the molecular basis of assembly mechanism of caspase-activating complexes have been performed. In this review, we summarize previous studies that have examined the structural and biochemical features of caspase-activating complexes. By analyzing the structural basis for the assembly mechanism of the caspase-activating complex, we hope to provide a comprehensive understanding of caspase activation by these important oligomeric complexes.
Curcumin Enhances Cytotoxic Effects of Bortezomib in Human Multiple Myeloma H929 Cells: Potential Roles of NF-κB/JNK
Authors: Bai Qing-Xian , Zhang Xiao-Yan
Published: April 2012

Combined curcumin and PS-341 treatment has been reported to enhance cytotoxicity and minimize adverse effects through ERK and p38MAPK mechanisms in human multiple myeloma cells. However, whether JNK plays similar role in this process remains unclear. In the present study, we found combined treatment altered NF-κB p65 expressions and distributions in multiple myeloma H929 cells. Western blot analysis showed combined treatment inactivated NF-κB while activated JNK signaling. Pre-treatment with JNK inhibitor SP600125 could attenuate NF-κB inactivation and restored H929 cells’ survival. These results suggested that curcumin might enhance the cytotoxicity of PS-341 by interacting with NF-κB, at least in part, through JNK mechanism.
Novel Drug Delivery System Based on Docetaxel-Loaded Nanocapsules as a Therapeutic Strategy Against Breast Cancer Cells
Authors: Sánchez-Moreno Paola , Boulaiz Houria , Ortega-Vinuesa Juan Luis , Peula-García José Manuel , Aránega Antonia
Published: April 2012

In the field of cancer therapy, lipid nanocapsules based on a core-shell structure are promising vehicles for the delivery of hydrophobic drugs such as docetaxel. The main aim of this work was to evaluate whether docetaxel-loaded lipid nanocapsules improved the anti-tumor effect of free docetaxel in breast cancer cells. Three docetaxel-loaded lipid nanocapsules were synthesized by solvent displacement method. Cytotoxic assays were evaluated in breast carcinoma (MCF-7) cells treated by the sulforhodamine B colorimetric method. Cell cycle was studied by flow cytometry and Annexin V-FITC, and apoptosis was evaluated by using propidium iodide assays. The anti-proliferative effect of docetaxel appeared much earlier when the drug was encapsulated in lipid nanoparticles than when it was free. Docetaxel-loaded lipid nanocapsules significantly enhanced the decrease in IC50 rate, and the treated cells evidenced apoptosis and a premature progression of the cell cycle from G(1) to G(2)-M phase. The chemotherapeutic effect of free docetaxel on breast cancer cells is improved by its encapsulation in lipid nanocapsules. This approach has the potential to overcome some major limitations of conventional chemotherapy and may be a promising strategy for future applications in breast cancer therapy.
Alcohol and Cardiovascular Disease—Modulation of Vascular Cell Function
Authors: Cahill Paul A. , Redmond Eileen M.
Published: April 2012

Alcohol is a commonly used drug worldwide. Epidemiological studies have identified alcohol consumption as a factor that may either positively or negatively influence many diseases including cardiovascular disease, certain cancers and dementia. Often there seems to be a differential effect of various drinking patterns, with frequent moderate consumption of alcohol being salutary and binge drinking or chronic abuse being deleterious to one’s health. A better understanding of the cellular and molecular mechanisms mediating the many effects of alcohol consumption is beginning to emerge, as well as a clearer picture as to whether these effects are due to the direct actions of alcohol itself, or caused in part by its metabolites, e.g., acetaldehyde, or by incidental components present in the alcoholic beverage (e.g., polyphenols in red wine). This review will discuss evidence to date as to how alcohol (ethanol) might affect atherosclerosis that underlies cardiovascular and cerebrovascular disease, and the putative mechanisms involved, focusing on vascular endothelial and smooth muscle cell effects.
Benefits of Combined GPS/GLONASS with Low-Cost MEMS IMUs for Vehicular Urban Navigation
Authors: Angrisano Antonio , Petovello Mark , Pugliano Giovanni
Published: April 2012

The integration of Global Navigation Satellite Systems (GNSS) with Inertial Navigation Systems (INS) has been very actively researched for many years due to the complementary nature of the two systems. In particular, during the last few years the integration with micro-electromechanical system (MEMS) inertial measurement units (IMUs) has been investigated. In fact, recent advances in MEMS technology have made possible the development of a new generation of low cost inertial sensors characterized by small size and light weight, which represents an attractive option for mass-market applications such as vehicular and pedestrian navigation. However, whereas there has been much interest in the integration of GPS with a MEMS-based INS, few research studies have been conducted on expanding this application to the revitalized GLONASS system. This paper looks at the benefits of adding GLONASS to existing GPS/INS(MEMS) systems using loose and tight integration strategies. The relative benefits of various constraints are also assessed. Results show that when satellite visibility is poor (approximately 50% solution availability) the benefits of GLONASS are only seen with tight integration algorithms. For more benign environments, a loosely coupled GPS/GLONASS/INS system offers performance comparable to that of a tightly coupled GPS/INS system, but with reduced complexity and development time.
Polymer Recovery from Auto Shredder Residue by Projectile Separation Method
Authors: Lee Jason J. S. , Mo John P. T. , Wu Dong Yang
Published: April 2012

The number of vehicles on the road has been increasing at an enormous rate over the last decade. By 2015, the number of vehicles that reach the end of their life will be close to a million per year in Australia. Most metallic parts of the vehicle can be recycled but the plastic components and components of other materials are normally shredded and disposed in landfills. As more vehicles are using composite materials, the percentage of materials sent to landfill is alarming. This paper reviews existing polymer recycling techniques for End-of-Life Vehicles (ELVs) and proposes a more efficient electrostatic based projectile separation method. The test rig is at the preliminary stage of development and initial outcomes are promising.
Cellular stress conditions are reflected in the protein and RNA content of endothelial cell‐derived exosomes
Authors: de Jong Olivier G. , Verhaar Marianne C. , Chen Yong , Vader Pieter , Gremmels Hendrik , Posthuma George , Schiffelers Raymond M. , Gucek Marjan , van Balkom Bas W.M.
Published: April 2012

Background

The healthy vascular endothelium, which forms the barrier between blood and the surrounding tissues, is known to efficiently respond to stress signals like hypoxia and inflammation by adaptation of cellular physiology and the secretion of (soluble) growth factors and cytokines. Exosomes are potent mediators of intercellular communication. Their content consists of RNA and proteins from the cell of origin, and thus depends on the condition of these cells at the time of exosome biogenesis. It has been suggested that exosomes protect their target cells from cellular stress through the transfer of RNA and proteins. We hypothesized that endothelium‐derived exosomes are involved in the endothelial response to cellular stress, and that exosome RNA and protein content reflect the effects of cellular stress induced by hypoxia, inflammation or hyperglycemia.

Methods

We exposed cultured endothelial cells to different types of cellular stress (hypoxia, TNF‐α‐induced activation, high glucose and mannose concentrations) and compared mRNA and protein content of exosomes produced by these cells by microarray analysis and a quantitative proteomics approach.

Results

We identified 1,354 proteins and 1,992 mRNAs in endothelial cell‐derived exosomes. Several proteins and mRNAs showed altered abundances after exposure of their producing cells to cellular stress, which were confirmed by immunoblot or qPCR analysis.

Conclusion

Our data show that hypoxia and endothelial activation are reflected in RNA and protein exosome composition, and that exposure to high sugar concentrations alters exosome protein composition only to a minor extend, and does not affect exosome RNA composition.
Diverse subpopulations of vesicles secreted by different intracellular mechanisms are present in exosome preparations obtained by differential ultracentrifugation
Authors: Bobrie Angélique , Colombo Marina , Krumeich Sophie , Raposo Graça , Théry Clotilde
Published: April 2012

Exosomes are extracellular vesicles of 50 to 100 nm in diameter, released by many cell types. Exosomes are formed inside the cell in intracellular endosomal compartments and are secreted upon fusion of these compartments with the plasma membrane. Cells also secrete other types of membrane vesicles, for instance, by outward budding from the plasma membrane, and although some of them clearly differ from exosomes by their structural features (larger size), others are possibly more difficult to separate. Here, using Rab27a inhibition to modulate exosome secretion, we show the existence of at least 2 distinct populations of vesicles after purification by classical ultracentrifugation from mouse tumor cell conditioned medium. Rab27a inhibition lead to decreased vesicular secretion of some conventional markers of exosomes (CD63, Tsg101, Alix and Hsc70) but did not affect secretion of others (CD9 and Mfge8). By electron microscopy, CD9 was observed on vesicles of various sizes, ranging from 30 nm to more than 150 nm in diameter. Flotation onto sucrose gradients showed different proportions of CD63, CD9 and Mfge8 not only in fractions of densities classically described for exosomes (around 1.15 g/ml) but also in fractions of densities over 1.20 g/ml, indicating the presence of heterogenous vesicle populations. CD9 and Mfge8 were also found in large vesicles pelleted at low speed and can thus not be considered as specific components of endosome‐derived vesicles. We propose that the most commonly used protocols for exosome preparations co‐purify vesicles from endosomal and other origins, possibly the plasma membrane. Future work will be required to improve techniques for accurate purification and characterization of the different populations of extracellular vesicles.
Characterization,GFPGene Nucleofection, and Allotransplantation in Injured Tendons of Ovine Amniotic Fluid-Derived Stem Cells
Authors: Colosimo A. , Curini V. , Russo V. , Mauro A. , Bernabò N. , Marchisio M. , Alfonsi M. , Muttini A. , Mattioli M. , Barboni B.
Published: April 2012

Amniotic fluid has drawn increasing attention in the recent past as a cost-effective and accessible source of fetal stem cells. Amniotic fluid-derived mesenchymal stem cells (AFMSCs) that display high proliferation rate, large spectrum of differentiation potential, and immunosuppressive features are considered optimal candidates for allogeneic repair of mesenchymal damaged tissues. In this study, ovine AFMSCs (oAFMSCs) isolated from 3-month-old sheep fetuses were characterized for their proliferation rate, specific surface antigen and pluripotency marker expression, genomic stability, and mesenchymal lineage differentiation during their in vitro expansion (12 passages) and after nucleofection. The high proliferation rate of oAFMSCs gradually decreased during the first six subculture passages while the expression of surface molecules (CD29, CD58, CD166) and of pluripotency-associated markers (OCT4, TERT, NANOG, SOX2), the in vitro osteogenic differentiation potential, and a normal karyotype were maintained. Afterwards, oAFMSCs were nucleofected with a selectable plasmid coding for green fluorescent protein (GFP) using two different programs, U23 and C17, previously optimized for human mesenchymal stem cells. Transfection efficiencies were ~63% and ~37%, while cell recoveries were ~10% and ~22%, respectively. Nucleofected oAFMSCs expressing the GFP transgene conserved their pluripotency marker profile and retained a normal karyotype and the osteogenic differentiation ability. Seven single clones with a GFP expression ranging from 80% to 97% were then isolated and expanded over 1 month, thus providing stably transfected cells with long-term therapeutic potential. The in vivo behavior of GFP-labeled oAFMSCs was tested on a previously validated preclinical model of experimentally induced Achille's tendon defect. The allotransplanted oAFMSCs were able to survive within the host tissue for 1 month enhancing the early phase of tendon healing as indicated by morphological and biomechanical results. Altogether these data suggest that genetically modified oAFMSCs might represent a valuable tool for in vivo preclinical studies in a highly valid translational model.
Aryl nitrile oxide cycloaddition reactions in the presence of pinacol boronic acid ester
Authors: Harding Sarah L , Marcuccio Sebastian M , Savage G Paul
Published: April 2012

An aryl substrate with dual functionality consisting of a nitrile oxide and a pinacolyl boronate ester was prepared by mild hypervalent iodine oxidation (diacetoxyiodobenzene) of the corresponding aldoxime, without decomposition of the boronate functionality. The nitrile oxide was trapped in situ with a variety of dipolarophiles to yield aryl isoxazolines with the boronate ester function intact and available for subsequent reaction.
p38 Mitogen-activated Protein Kinase and Nuclear Factor-κB Facilitate CD40-mediated Salivary Epithelial Cell Death
Authors: PING LI , OGAWA NORIYOSHI , ZHANG YANG , SUGAI SUSUMU , MASAKI YASUFUMI , WEIGUO XIAO
Published: April 2012

Objective.

Our previous studies indicated that CD40-mediated Fas-dependent apoptosis is important for the glandular destruction of Sjögren’s syndrome (SS), although other immune and nonimmune mechanisms are also involved in exocrine dysfunction. We investigated the roles of p38 mitogen-activated protein kinase (p38MAPK) and nuclear factor-κB (NF-κB) in salivary epithelial cell death in SS.

Methods.

Expression of p38, phosphorylated p38 (pp38), and IκB-α was examined by Western blotting upon CD40 ligation. Activity of NF-κB induced by anti-CD40 monoclonal antibody (mAb) was examined by electrophoretic mobility shift assay (EMSA) and Western blotting. Expression of Fas was analyzed by flow cytometry and Western blotting with or without the p38-specific inhibitor SB203580 or the NF-κB-specific inhibitor caffeic acid phenethyl ester (CAPE). Induction of apoptosis in salivary epithelial cells was examined by DNA fragmentation and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay. Expression of phosphorylated p38MAPK and NF-κB was measured by immunohistochemistry.

Results.

pp38MAPK and NF-κB p65 were predominantly expressed in the ductal and acinar epithelium adjacent to lymphoid infiltrates of SS salivary gland by immunohistochemistry. CD40 ligation strongly enhanced p38MAPK and NF-κB activity by EMSA and Western blotting in cultured salivary epithelial cells. Treatment of cells with anti-CD40 mAb resulted in significantly upregulated Fas expression and induction of Fas-dependent apoptosis. Inhibition of p38MAPK and NF-κB activity by SB203580 and/or CAPE reduced Fas expression and apoptosis in salivary epithelial cells, establishing p38MAPK and NF-κB as proapoptotic factors in this context.

Conclusion.

CD40 ligation plays an important role in activation of p38MAPK, NF-κB, and Fas molecules to initiate proapoptotic signaling. p38MAPK and NF-κB collaborate in regulation of proapoptotic signaling in CD40-mediated Fas-dependent apoptosis in salivary epithelial cells.
Des rites humains autour de la mort
Authors: Biot Christian
Published: April 2012

Résumé Autour de la mort d’un être humain, les rites funéraires évoluent en fonction de l’attachement des individus et des groupes familiaux et sociaux à l’égard des systèmes de croyances et de références portés par les religions et par les groupes philosophiques. Comment percevoir et prendre en considération, dans l’expérience quotidienne des cérémonies, cette évolution ? Comment percevoir et laisser s’exprimer la permanence de la question sur la vie humaine : est-elle sensée ?
Des femmes et des cendres
Authors: Jandrok Thierry
Published: April 2012

Résumé Que deviennent les restes cinéraires lorsqu’ils échappent au registre de la loi et des rituels funéraires ? À travers le court exposé de trois cas cliniques, nous étudierons les destins des cendres de maris dont les épouses ont conservé la garde, du moins pour un temps. Les deux premières ont une façon perverse de traiter ses restes. Elles gardent un œil sur eux, comme si aucune évasion n’était plus possible. Quant à la troisième, elle respecte la volonté du défunt et ce faisant libère sa conscience. Quels sens donner à ces usages singuliers, et dans quelques cas, non ritualisés des restes funéraires ?
Corrida de muerte, ritualisations et symbolismes
Authors: Hardouin-Fugier Élisabeth
Published: April 2012

Résumé La mort du torero, autrefois constitutionnelle de la corrida, devient aujourd’hui accidentelle, mais son ombre demeure. Dès la codification de 1796, les actions se ritualisent, sous l’aspect festif d’un scénario mimant une exécution publique rigoureusement juridicisée. Au XX e siècle, de combattant, le matador, devient artiste. Dans les arts plastiques, deux œuvres érotico-pornographiques témoignent d’un environnement symbolique exacerbé, mais dans l’arène, l’écorchoir n’est pas un mythe.
Épidémiologie politique des études cas-témoins (1926-1950)
Authors: Morabia Alfredo
Published: April 2012

Résumé L’épidémiologie politique des études cas-témoins consiste ici à comparer le contexte de publication d’un groupe d’études allemandes de la période nazie sur l’association entre tabac et cancer du poumon à celui d’un groupe d’études cas-témoins, une anglaise et deux américaines, de l’après-guerre, sur le même thème. En Allemagne nazie, le contexte politique était favorable à une incrimination des méfaits du tabac. Deux études comparant des cas de cancer du poumon à des personnes « normales », publiées en 1939 et en 1943, conclurent à juste titre que le tabac était une cause de cancer du poumon. Elles n’étaient cependant pas les premières à le faire, leur méthodologie n’était pas rigoureuse, et il est probable qu’elles avaient pour but d’apporter une légitimité scientifique au projet nazi d’utiliser l’opposition au tabac comme un instrument d’ingénierie raciale et de militarisation de la société allemande. En 1950, en revanche, les épidémiologistes anglais et américains rencontrèrent des difficultés pour publier des résultats montrant un risque accru de cancer du poumon chez les fumeurs. L’étude cas-témoins anglaise était méthodologiquement solide, mais elle se heurtait à la bonne image du tabac dans les sociétés démocratiques et à la puissance du lobby des producteurs de tabac. Toutefois, par leur qualité, les études épidémiologiques de l’après-guerre produisirent des résultats qui furent utiles à la reconnaissance officielle du tabac comme cause du cancer du poumon.
Origines de l'étude prospective de cohorte : Épidémiologie cardio-vasculaire américaine et étude de Framingham
Authors: Giroux Élodie
Published: April 2012

Résumé Au début du xx e siècle et plus particulièrement dans la décade qui suivit la seconde guerre mondiale, la formalisation et l’usage de plus en plus fréquent des méthodes d’enquête de l’« étude cas-témoins » et de l’« étude prospective de cohorte » furent déterminants dans le développement de la recherche étiologique en épidémiologie. L’histoire de l’étude prospective de cohorte est bien connue dans l’épidémiologie du cancer ; cette histoire s’inscrit dans le contexte de la controverse sur le rôle du tabagisme dans le cancer du poumon. Dans cet article, nous nous intéressons aux origines de la méthode de l’étude prospective de cohorte dans l’épidémiologie cardio-vasculaire américaine, en particulier dans l’étude de Framingham. Cette dernière est en effet devenue emblématique de ce plan d’étude et des succès de la recherche étiologique en épidémiologie cardio-vasculaire. La comparaison avec l’épidémiologie du cancer du poumon permet d’identifier un style et des origines différentes du plan de l’étude de cohorte dans l’épidémiologie cardio-vasculaire. Nous montrons que ce plan d’étude a des origines dans les études longitudinales d’incidence menées au début du xx e siècle dans le cadre de l’épidémiologie des services américains de santé publique d’une part, et dans les études cliniques de suivi d’autre part.
Stability of Therapeutic Retreatment of Corneal Wavefront Customized Ablation With the SCHWIND CAM: 4-year Data
Authors: Aslanides Ioannis M. , Kolli Sai , Padron Sara , Arba Mosquera Samuel
Published: April 2012

PURPOSE:

To evaluate the long-term outcomes of aspheric corneal wavefront ablation profiles for excimer laser retreatment.

METHODS:

Eighteen eyes that had previously undergone LASIK or photorefractive keratectomy (PRK) were retreated with LASIK using the corneal wavefront ablation profile. Custom Ablation Manager (SCHWIND eye-tech-solutions, Kleinostheim, Germany) software and the ESIRIS flying spot excimer laser system (SCHWIND) were used to perform the ablations. Refractive outcomes and wavefront data are reported up to 4 years after retreatment. Pre- and postoperative data were compared with Student
t
tests and (multivariate) correlation tests.
P
<.05 was considered statistically significant. A bilinear correlation of various postoperative wavefront aberrations versus planned correction and preoperative aberration was performed.

RESULTS:

Mean manifest refraction spherical equivalent (MRSE) before retreatment was −0.38±1.85 diopters (D) and −0.09±0.22 D at 6 months and −0.10±0.38 D at 4 years postoperatively. The reduction in MRSE was statistically significant at both postoperative time points (
P
<.005). Postoperative aberrations were statistically lower (spherical aberration
P
<.05; coma
P
<.005; root-mean-square higher order aberration
P
<.0001) at 4 years postoperatively. Distribution of the postoperative uncorrected distance visual acuity (
P
<.0001) and corrected distance visual acuity (
P
<.01) were statistically better than preoperative values.

CONCLUSIONS:

Aspheric corneal wavefront customization with the ESIRIS yields visual, optical, and refractive results comparable to those of other wavefront-guided customized techniques for the correction of myopia and myopic astigmatism. The corneal wavefront customized approach shows its strength in cases where abnormal optical systems are expected. Systematic wavefront customized corneal ablation appears safe and efficacious for retreatment cases.