bluuebunny/crossref_metadata_2025 huggingface dataset:
Correlation of Care Process Measures With Childhood Asthma Exacerbations
Authors: Vernacchio Louis , Trudell Emily K. , Muto Jennifer M.
Published: December 2012

OBJECTIVE:

We sought to define processes of pediatric asthma care identifiable through administrative data that correlate with asthma exacerbations for use in quality improvement.

METHODS:

Commercially insured children aged 5 to 17 years from the Pediatric Physicians’ Organization at Children’s, an independent practice association affiliated with Boston Children’s Hospital, with persistent asthma in 2008, 2009, or 2010 were identified. The correlations of various process measures with asthma exacerbations, defined as hospitalizations or emergency department visits for asthma or outpatient visits for asthma with an oral steroid prescription, were analyzed by using logistic regression.

RESULTS:

Significant correlations were found between filling 0 vs ≥1 controller medications in all years (relative risk [RR] 3.35, 2.11, and 2.71 in 2008, 2009, and 2010, respectively) although only 4% of subjects overall filled no controller medications. The asthma medication ratio (controller prescriptions divided by total asthma prescriptions) was also associated with exacerbations, with the lowest 2 quartiles having a lower risk compared with the highest in all years (RR 2.27, 2.45, and 2.39 for the lowest; RR 2.10, 2.02, and 2.65 for the second quartile in 2008, 2009, and 2010, respectively).

CONCLUSIONS:

Filling 0 vs ≥1 controllers and the asthma medication ratio correlated with asthma exacerbations. Although both might serve as quality improvement metrics for pediatric asthma, we favor the asthma medication ratio because it applies to a broader range of children with asthma and better reflects the recommended clinical approach for children with persistent asthma.
Trends and Socioeconomic Correlates of Adolescent Physical Fighting in 30 Countries
Authors: Pickett William , Molcho Michal , Elgar Frank J. , Brooks Fiona , de Looze Margaretha , Rathmann Katharina , ter Bogt Tom F.M. , Nic Gabhainn Saoirse , Sigmundová Dagmar , Gaspar de Matos Margarida , Craig Wendy , Walsh Sophie D. , Harel-Fisch Yossi , Currie Candace
Published: December 2012

BACKGROUND AND OBJECTIVES:

No recent international studies provide evidence about its prevalence, trends, or social determinants of physical fighting in adolescents. We studied cross-national epidemiologic trends over time in the occurrence of frequent physical fighting, demographic variations in reported trends, and national wealth and income inequality as correlates.

METHODS:

Cross-sectional surveys were administered in school settings in 2002, 2006, and 2010. Participants (N = 493874) included eligible and consenting students aged 11, 13, and 15 years in sampled schools from 30 mainly European and North American countries. Individual measures included engagement in frequent physical fighting, age, gender, participation in multiple risk behaviors, victimization by bullying, and family affluence. Contextual measures included national income inequality, absolute wealth and homicide rates. Temporal measure was survey cycle (year).

RESULTS:

Frequent physical fighting declined over time in 19 (63%) of 30 countries (from descriptive then multiple Poisson regression analyses). Contextual measures of absolute wealth (relative risk 0.96, 95% confidence interval 0.93–0.99 per 1 SD increase in gross domestic product per capita) but not income inequality (relative risk 1.01, 95% confidence interval 0.98–1.05 per 1 SD increase) related to lower levels of engagement in fighting. Other risk factors identified were male gender, younger age (11 years), multiple risk behaviors, victimization by bullying, and national homicide rates.

CONCLUSIONS:

Between 2002 and 2010, adolescent physical fighting declined in most countries. Specific groups of adolescents require targeted violence reduction programs. Possible determinants responsible for the observed declines are discussed.
Performance of encased granular columns considering shear-induced volumetric dilation of the fill material
Authors: Hong Y.-S.
Published: December 2012

ABSTRACT: This numerical study investigates the behaviour of geosynthetic-encased sand columns. Based on an elastic-plastic constitutive model used with the non-associated flow rule, the prominent expansive behaviour of medium to dense sands is characterised. Numerical analysis results are verified via laboratory triaxial tests on encased sand columns, where the sand mechanical properties are extracted from simple experimental tests. The tested sand columns in the experiments consist of two sands, encased by sleeves fabricated from two geotextiles. This verification demonstrates that the sand volumetric strain profoundly affects the induced confining pressure of an encased column. Exactly how the encasement stiffness, strength and diameter of the granular column influence encased column response is also studied using numerical analyses. Numerical results indicate that the encasement induces additional confining pressure, subsequently preventing strength yield in the encased columns before the encasement reaches its yield strength. These results further demonstrate that the ratio of encasement stiffness to column diameter significantly affects the response of a granular column. Moreover, it may be unnecessary to encase a small-diameter column with a stiff encasement, whereas encasing a large diameter column with a low-stiffness encasement may produce a limited reinforcing effect.
Synthesis and characterization of a novel rosin-based monomer: free-radical polymerization and epoxy curing
Authors: Wang Jifu , Yu Juan , Liu Yupeng , Chen Ying , Wang Chunpeng , Tang Chuanbing , Chu Fuxiang
Published: December 2012

Rosin, an abundant raw material from pine trees, has attracted much attention due to its use as a feedstock for the preparation of polymers in the age of the depletion of crude oil. Maleopimaric acid (MPA) is one of most impor-tant rosin derivatives obtained via Diels-Alder reaction between gum rosin and maleic anhydride. In this article, the authors reported a synthetic strategy to prepare a novel vinyl ester of MPA (AMPA) by sequential reaction of MPA with oxalyl chloride and allyl alcohol. The structure and properties of AMPA were characterized by fourier transform infrared spectroscopy (FT-IR), gas chromatography–mass spectrometry, 1H NMR, 13C NMR and differential scanning calorimetry (DSC). The results showed that AMPA has high purity and could undergo free-radical polymerization. In particular, AMPA was used as a curing agent to carry out noniso-thermal curing reaction with epoxy resin by DSC, and cured polymers were characterized by FT-IR and thermogra-vimetric analysis. The results suggested that AMPA has a great potential to prepare rosin-based unsaturated resin and epoxy resin.
The Difficulties of Teaching IFRS in Russia
Authors: Vysotskaya Anna , Prokofieva Maria
Published: December 2012

In recent years Russia has undergone radical changes in all spheres of life, prompted by the transition from a centrally planned economy to an open market-based economy. Dramatic changes such as privatization, the development of private business entities, and foreign investment in the Russian economy have brought changes in the accounting field, including those arising from a decision to adopt the International Financial Reporting Standards (IFRS). While Russia has not yet implemented IFRS in full for all types of businesses, it has made considerable steps over the years to introduce IFRS into its accounting system. From 2012, Russia is adopting IFRS fully for publicly listed companies. This paper provides an overview of the changes in accounting education that have ensued from the decision to adopt IFRS, including the educational reforms that have taken place. The paper reviews these changes from a historical perspective and investigates existing problems caused by the transition.
Effect of text message follow-up on patient's self-reported level of pain and anxiety
Authors: Keith Daniel J. , Rinchuse Daniel J. , Kennedy Meghan , Zullo Thomas
Published: December 2012

Objectives:

To determine whether a text message reduces the severity of patient self-reported levels of pain and anxiety following initial placement of orthodontic appliances.

Materials and Methods:

Thirty-nine orthodontic patients were randomly assigned to one of two groups and matched for age, gender, and bracket type (self-ligating vs conventional). The subjects completed baseline questionnaires to ascertain their levels of pain and anxiety before initiating orthodontic treatment. Following the initial appointment, subjects completed the pain questionnaire and anxiety inventory at the same time daily for 1 week. One group received a structured text message showing concern and reassurance, while the second group served as a control and received no postprocedural communication.

Results:

There was a statistically significant difference in pain in relation to time between the text message group and the control group as it was demonstrated that demonstrated that compared with the text message group, mean pain intensity increased and selfreported discomfort was longer in the control group. Anxiety was determined to be at its peak the day following initial orthodontic appliance placement and gradually tapered off from that time point. No intergroup difference was noted when analyzing anxiety.

Conclusions:

This study demonstrated that a text message sent from an orthodontic office following initial appliance placement resulted in a lower level of patient's self-reported pain. Additionally, patient anxiety is at its peak the day following the initial appointment and decreases from that point forward.
Metabolic Programming of MEST DNA Methylation by Intrauterine Exposure to Gestational Diabetes Mellitus
Authors: El Hajj Nady , Pliushch Galyna , Schneider Eberhard , Dittrich Marcus , Müller Tobias , Korenkov Michael , Aretz Melanie , Zechner Ulrich , Lehnen Harald , Haaf Thomas
Published: December 2012

Epigenetic processes are primary candidates when searching for mechanisms that can stably modulate gene expression and metabolic pathways according to early life conditions. To test the effects of gestational diabetes mellitus (GDM) on the epigenome of the next generation, cord blood and placenta tissue were obtained from 88 newborns of mothers with dietetically treated GDM, 98 with insulin-dependent GDM, and 65 without GDM. Bisulfite pyrosequencing was used to compare the methylation levels of seven imprinted genes involved in prenatal and postnatal growth, four genes involved in energy metabolism, one anti-inflammatory gene, one tumor suppressor gene, one pluripotency gene, and two repetitive DNA families. The maternally imprinted MEST gene, the nonimprinted glucocorticoid receptor NR3C1 gene, and interspersed ALU repeats showed significantly decreased methylation levels (4–7 percentage points for MEST, 1–2 for NR3C1, and one for ALUs) in both GDM groups, compared with controls, in both analyzed tissues. Significantly decreased blood MEST methylation (3 percentage points) also was observed in adults with morbid obesity compared with normal-weight controls. Our results support the idea that intrauterine exposure to GDM has long-lasting effects on the epigenome of the offspring. Specifically, epigenetic malprogramming of MEST may contribute to obesity predisposition throughout life.
Decreased Transcription of ChREBP-α/β Isoforms in Abdominal Subcutaneous Adipose Tissue of Obese Adolescents With Prediabetes or Early Type 2 Diabetes
Authors: Kursawe Romy , Caprio Sonia , Giannini Cosimo , Narayan Deepak , Lin Aiping , D’Adamo Ebe , Shaw Melissa , Pierpont Bridget , Cushman Samuel W. , Shulman Gerald I.
Published: December 2012

Insulin resistance associated with altered fat partitioning in liver and adipose tissues is a prediabetic condition in obese adolescents. We investigated interactions between glucose tolerance, insulin sensitivity, and the expression of lipogenic genes in abdominal subcutaneous adipose and liver tissue in 53 obese adolescents. Based on their 2-h glucose tests they were stratified in the following groups: group 1, 2-h glucose level <120 mg/dL; group 2, 2-h glucose level between 120 and 140 mg/dL; and group 3, 2-h glucose level >140 mg/dL. Liver and adipose tissue insulin sensitivity were greater in group 1 than in group 2 and group 3, and muscle insulin sensitivity progressively decreased from group 1 to group 3. The expression of the carbohydrate-responsive element-binding protein (ChREBP) was decreased in adipose tissue but increased in the liver (eight subjects) in adolescents with impaired glucose tolerance or type 2 diabetes. The expression of adipose ChREBPα and ChREBPβ was inversely related to 2-h glucose level and positively correlated to insulin sensitivity. Improvement of glucose tolerance in four subjects was associated with an increase of ChREBP/GLUT4 expression in the adipose tissue. In conclusion, early in the development of prediabetes/type 2 diabetes in youth, ChREBPβ expression in adipose tissue predicts insulin resistance and, therefore, might play a role in the regulation of glucose tolerance.
Some Common Indices of Group Diversity: Upper Boundaries
Authors: Solanas Antonio , Selvam Rejina M. , Navarro José , Leiva David
Published: December 2012

Workgroup diversity can be conceptualized as variety, separation, or disparity. Thus, the proper operationalization of diversity depends on how a diversity dimension has been defined. Analytically, the minimal diversity must be obtained when there are no differences on an attribute among the members of a group, however maximal diversity has a different shape for each conceptualization of diversity. Previous work on diversity indexes indicated maximum values for variety (e.g., Blau's index and Teachman's index), separation (e.g., standard deviation and mean Euclidean distance), and disparity (e.g., coefficient of variation and the Gird coefficient of concentration), although these maximum values are not valid for all group characteristics (i.e., group size and group size parity) and attribute scales (i.e., number of categories). We demonstrate analytically appropriate upper boundaries for conditional diversity determined by some specific group characteristics, avoiding the bias related to absolute diversity. This will allow applied researchers to make better interpretations regarding the relationship between group diversity and group outcomes.
Attitudes of Future Physical Education Teachers in Turkey toward Lesbians and Gay Men
Authors: Saraç Leyla
Published: December 2012

This study explored male and female physical education majors' (149 men, 97 women) attitudes toward lesbians and gays in Turkey. The short form of the Attitudes toward Lesbians and Gay Men Scale was used to assess attitudes toward lesbians and gay men in relation to the education majors' sex, year of schooling, and whether or not he/she had a lesbian/gay friend or acquaintance. Female students had more positive attitudes toward gay men compared with males, and male and female students' attitudes toward lesbians were similar. Furthermore, no significant differences were found among the different cohort years in terms of attitudes toward lesbians and gay men. Results also revealed that students who had lesbian/gay friends or acquaintances held more positive attitudes toward gay men than those who did not. However, their attitudes were similar toward lesbians.
Predicting Cement–Admixture Incompatibilities with Cement Paste Rheology
Authors: Mukhopadhyay Anal K. , Jang Sehoon
Published: December 2012

The complex interaction between cement and the chemical and mineral admixtures in concrete mixture sometimes causes unpredictable concrete performance in the field, generally defined as concrete incompatibilities. Cement paste rheology measurements—rather than traditional workability tests—can effectively detect these incompatibilities in concrete before the concrete is placed to avoid setting-time, workability, and curing-related issues, which sometimes lead to early-age cracking, especially in severe weather conditions. The objective of the present study is to examine the applicability of the Superpave® dynamic shear rheometer to measure cement paste rheology and to identify incompatibilities between cement and the admixtures based on cement paste rheological behavior. Extensive laboratory investigation showed that dynamic shear rheometer in modified form could measure cement paste rheology with permissible repeatability and sensitivity and has great potential in identifying the incompatibilities between cement and the admixtures. Heat of hydration data from an isothermal calorimeter test and the setting time results of the mixtures studied have strongly supported the rheology results. A procedure to formulate the rheology-based acceptance criteria has been developed on the basis of the available test results. Further refinement of these acceptance criteria based on detailed work covering a wide range of incompatibilities and validation through a round-robin testing program is warranted. This research will ultimately help concrete producers and district laboratories detect problematic combinations of concrete ingredients during the mixture design process.
Development of Precision Statement for Concrete Surface Resistivity
Authors: Icenogle Patrick J. , Rupnow Tyson D.
Published: December 2012

Seventeen surface resistivity meters and 17 operators participated in the round-robin testing conducted at the Louisiana Transportation Research Center over 2 days. The tests were conducted side by side, and the individual meter's results were compared. Eight mixtures representing multiple permeability classes were tested with two replicates for each mixture. A precision statement was developed for use with Louisiana Department of Transportation and Development's TR 233, Surface Resistivity Indication of Concrete's Ability to Resist Chloride Ion Penetration. The single operator coefficient of variation (CV) of a single test result has been found to be 2.2%. Therefore, the results of two properly conducted tests by the same operator on concrete samples from the same batch and of the same diameter should not differ by more than 6.2%. The multilaboratory CV of a single test result has been found to be 3.9%. Therefore, the results of two properly conducted tests in different laboratories on the same material should not differ by more than 11%.
Durability of Pavement Concretes Made with Recycled Concrete Aggregates
Authors: Jain Jitendra , Verian Kho Pin , Olek Jan , Whiting Nancy
Published: December 2012

There is a growing trend to replace the traditional ingredients of concrete pavement mixtures with more sustainable materials from a perspective of both the cost of raw materials and the carbon dioxide footprint. The availability of quality natural aggregates, which make up about 70% to 80% of concrete (by volume), is becoming more limited because of environmental restrictions on quarrying operations and longer hauling distances. The other major concern is disposal of old concrete pavements, which unless used as fill or base material for construction of new roadways, will have to be placed in the landfills. In this study, recycled concrete aggregates (RCA) obtained from crushing old concrete pavement were used as coarse aggregates at 0%, 30%, 50%, and 100% replacement levels (by mass) for natural virgin aggregates (NVA). Concrete mixtures were designed and produced to meet the concrete pavement requirements for air content, slump, and flexural strength stipulated by the Indiana Department of Transportation. All concrete mixtures were produced with 18.5% to 20.0% of the cement replaced (by mass) with ASTM C618 Class C fly ash. The physical and mechanical testing involved evaluation of slump, air content, and development of both flexural and compressive strengths. In addition, durability was assessed with the freeze–thaw test, scaling test, rapid chloride permeability (RCP) test, and non–steady state migration test. The most advantageous dosages for replacing NVA with RCA for concrete pavements were found to be 50%, on the basis of fresh concrete properties and the results of strength and durability tests. The applicability of electrical impedance spectroscopy for quick performance appraisal is presented on the basis of the experimental relationship between the RCP charge and bulk resistance of concrete.
Freeze–Thaw Durability and Salt Scaling Resistance Assessment of Portland Cement Concrete Composite Pavement
Authors: Vancura Mary , Tompkins Derek , Khazanovich Lev
Published: December 2012

The SHRP 2 R21 project on composite pavement investigated the durability of various mixtures of portland cement concrete (PCC) used in the construction of a two-layer composite PCC pavement. Project consultants in Europe, where composite PCC over PCC pavement was more common than in the United States, advised the R21 research team to consider using the CIF (capillary suction, internal damage, and freeze–thaw) standard of the International Union of Laboratories and Experts in Construction Materials, Systems, and Structures (RILEM), Paris, rather than the familiar ASTM standards. As a result, the R21 project adopted the RILEM CIF standard to evaluate the freeze–thaw durability and salt scaling resistance of concretes. The research also explored a modified RILEM CIF test (using pure water instead of a sodium chloride solution in scaling tests) alongside the standard RILEM CIF tests. The paper describes this experience to expose other institutions and agencies in the United States to the RILEM standards for the freeze–thaw durability and salt scaling resistance testing of concretes.
Performance of Slag Cement in Hydraulic Cement Concrete
Authors: Lane D. Stephen
Published: December 2012

The Virginia Department of Transportation began to allow the use of slag cement in hydraulic cement concretes in 1985; its use has steadily increased since then. Several years ago a study was conducted to investigate the performance of bridge decks constructed with hydraulic cement concretes containing straight portland cement and portland cement plus slag cement with a specified water–cementitious materials ratio of 0.45. At the time of the field work, these decks were 12 to 16 years old. In addition to general observations of deck condition, cores were extracted from the decks for petrographic examination of internal condition and determination of concrete transport properties by using electrical conductivity and rate of water absorption. Overall, the slag cement concretes performed well with a tendency toward lower transport properties and showed no inherent tendency for scaling. Some evidence of alkali–aggregate reactivity was observed with evident damage in one case, although it was not clear whether an insufficient amount of slag cement was used or slag cement would simply be ineffective in this case. Overall, the performance and experience with slag cement were favorable.
Lowering the Carbon Footprint of Concrete by Reducing Clinker Content of Cement
Authors: Thomas Michael , Barcelo Laurent , Blair Bruce , Cail Kevin , Delagrave Anik , Kazanis Ken
Published: December 2012

Significant efforts have been made to reduce carbon dioxide (CO2) emissions associated with the manufacture of portland cement, primarily by making the process more energy efficient and increasing the use of alternative fuels. Further reductions in CO2 can be achieved by lowering the clinker component of the cement because the pyroprocessing used to manufacture clinker produces approximately 1 tonne of CO2 for every tonne of clinker. Traditionally reductions in the clinker content of cement have been achieved by producing blended cement consisting of portland cement combined with a supplementary cementing material (SCM). In Canada, it is now permitted to intergrind up to 15% limestone with cement clinker to produce portland limestone cement or blended portland limestone cement. Recent trials were conducted at the Brookfield cement plant in Nova Scotia to evaluate the performance of a blended cement containing 15% ground, granulated blast furnace slag (an SCM) with that of a blended portland limestone cement containing the same amount of slag plus 12% interground limestone. Performance was evaluated by the construction of a section of concrete pavement using concrete mixtures produced with the two cements and various amounts of fly ash (another SCM). A wide range of laboratory tests were performed on the concrete specimens cast on site during the placement of the concrete pavement. The results indicated that the cements were of equivalent performance.
Reducing Curing Requirements for Pervious Concrete with a Superabsorbent Polymer for Internal Curing
Authors: Kevern John T. , Farney Chris
Published: December 2012

This paper presents the results of a research project to investigate reducing the need for curing pervious concrete under plastic by incorporating a superabsorbent polymer (SAP) normally intended for internal curing. Pervious concrete samples were produced with and without the SAP along with additional curing water. Compressive strength, unit weight, voids, and permeability testing was performed on hardened cylinders. Shrinkage was determined on beams for total and autogenous deformation with restrained ring testing. Moisture loss was determined with a modified version of the standard used to evaluate curing compounds, followed by rotary cutter surface abrasion. Field test sections were placed and cured under plastic or left open. The results show that mixtures containing the SAP had better workability and were stronger at equal void contents. The mixture containing the SAP had reduced shrinkage, moisture loss, and abrasion. After one winter, the uncured SAP field mixture had performance equal to the control mixture cured under plastic. Although preliminary, the results show that SAP has good potential to reduce curing requirements for pervious concrete under many environmental conditions.
Strength and Transport Properties of Concretes Modified with Coarse Limestone Powder to Compensate for Dilution Effects
Authors: Neithalath Narayanan , Cam Hieu T.
Published: December 2012

The use of a coarse limestone powder (median particle size of approximately 70 μm, five times larger than cement particles) as a cement replacement material results in a dilution effect. The magnitude of strength and transport property reduction is found to be greater than the magnitude of the cement replacement level. In this paper, methodologies to proportion concrete containing 10% to 15% of coarse limestone powder, in which the dilution effect is compensated through a combination of reduction in water-to-powder ratio and addition of 5% of silica fume, are discussed. Limestone–silica fume blended concretes at a reduced water-to-powder ratio (0.37 or 0.34, depending on limestone replacement level) show similar or higher 56-day compressive strengths than does the benchmark plain concrete with a water-to-cement ratio of 0.40. The rapid chloride permeability and non–steady state migration values of the modified concretes are evaluated along with their pore structure parameter extracted from electrical impedance data. The impact of water-to-powder reduction and silica fume incorporation is quantified through this pore structure parameter.
Development of Photocatalytic Pervious Concrete Pavement for Air and Storm Water Improvements
Authors: Asadi Somayeh , Hassan Marwa M. , Kevern John T. , Rupnow Tyson D.
Published: December 2012

Self-cleaning, air-purifying pervious concrete pavement is a promising technology that can be constructed with air-cleaning agents with superhydrophilic photocatalyst capabilities, such as titanium dioxide. Although this technology has the potential of supporting environment-friendly road infrastructure, its effectiveness depends on a number of design and operational parameters that need to be evaluated. The objective of this study was to evaluate the mechanical, environmental, and mix design parameters that influence the performance and effectiveness of photocatalytic pervious concrete pavement. To achieve this objective, an experimental program was conducted in which the effects of relative humidity level, pollutants' flow rate, and mix design parameters, including void ratio and depth of the photocatalytic layer, were investigated. Mechanical performance tests included porosity, unit weight, permeability, and compressive strength. The environmental efficiency of the samples to remove nitrogen oxides (NOx) from the atmosphere was measured in the laboratory. Results of the experimental program showed that increasing the depth of the photocatalytic layer increased NOx reduction efficiency. In addition, NOx removal efficiency decreased with the increase in the pollutant flow rate and increased with the increase in ultraviolet light intensity.
Analysis of Structural Compatibility at Interface between Asphalt Concrete Pavements and Orthotropic Steel Deck Surfaces
Authors: Bocci Edoardo , Canestrari Francesco
Published: December 2012

Orthotropic steel deck is the most suitable solution for long-span bridges by virtue of its low weight and good mechanical properties. However, this deck shows a lack of adhesion with ordinary paving materials; for this reason special bonding coats are usually applied on the steel surface. Polymer-modified bitumen, asphalt-based mastic, epoxy asphalt, and reinforced asphalt membrane have been used at the interface between the hot-mix asphalt (HMA) course and steel bridge decks. A description of these materials and their construction process is provided. In some extreme situations mechanical reinforcement is necessary to provide adequate bonding between the steel deck and the asphalt pavement. The aim of this study was the laboratory evaluation of the shear properties of smooth and reinforced steel interfaces, which were coated with a polymer-modified bitumen and placed between the steel deck and conventional HMA. A suitable specimen preparation procedure was first defined. Shear resistance was evaluated with the ASTRA shear test device to investigate the effects of temperature and normal stress on different types of HMA–steel interfaces. The results showed that reinforced steel interfaces guaranteed higher performance than did smooth interfaces, especially with increasing temperature. Reinforced steel interfaces can be considered as a reliable solution in cases of high-shear traffic-induced stresses.
Damage and Thixotropy in Asphalt Mixture and Binder Fatigue Tests
Authors: Pérez-Jiménez Félix , Botella Ramon , Miró Rodrigo
Published: December 2012

Fatigue cracking is considered one of the main damage mechanisms in asphalt pavement design. Design methods use fatigue laws obtained by laboratory testing of the materials involved. Typically, these tests consist of subjecting the asphalt mixture to cyclic loading until failure occurs. However, failure is associated not with specimen fracture (which is unusual), but with a slight decrease in the mechanical properties of the material, usually in the complex modulus. As a consequence, it is important to differentiate between real damage to the material and changes in its viscoelastic behavior and thixotropy. It is also crucial to account for the healing that occurs in asphalt material after rest periods. The above considerations are important in the fatigue testing of asphalt binders because these materials show pronounced viscoelastic behavior and thixotropy, especially when subjected to cyclic loading. This paper demonstrates that in many cases what is taken for fatigue failure during testing (i.e., a decrease in the complex modulus below half of its initial value) is actually thixotropy. Thus, the complex modulus can be recovered by reducing the loading or, as in this study, the strain applied. In contrast, asphalt mixtures experience irreversible damage, and depending on the asphalt binder, the thixotropic effects are more or less pronounced. This paper analyzes the failure criteria currently used in the fatigue testing of asphalt mixtures and binders and evaluates the parameters chosen, namely, complex modulus (G*) and phase angle (δ) to characterize asphalt binders (G*sin δ). A cyclic uniaxial tension–compression test under strain-controlled conditions was performed. Three test modalities were used: time sweeps (constant strain amplitude until total failure), increasing strain sweeps (increase in strain amplitude every 5,000 cycles), and up-and-down strain sweeps (alternating increases and decreases in strain amplitude).
Evaluation of New Dynamic Shear Rheometer Testing Geometry for Performance Testing of Crumb Rubber–Modified Binder
Authors: Baumgardner Gaylon , D'Angelo John A.
Published: December 2012

Crumb rubber modifier (CRM) has been used for many years in asphalt binder to provide improved field performance. Historically the increase in viscosity of CRM binder was measured with crude vane viscometers to quantify binder performance characteristics. The Superpave® system introduced far more accurate tools in the asphalt binder testing system to measure performance characteristics. As a result of testing geometry limitations, Superpave binder tests, specifically high-temperature testing, have generally not been applicable in testing CRM binders. This inability to test the material fully has limited the use and adoption of CRM binders. Well-known geometries in the rheology field, specifically coaxial cylinder geometries or cup and bob, can handle the larger particle sizes typically used as CRM. However, these geometries are not familiar in the asphalt industry. This study investigated the ability of the cup-and-bob geometry to test neat, polymer-modified, and CRM binders to determine if it could provide similar rheological results for both Superpave and multiple stress creep recovery (MSCR) testing. It concluded that the cup-and-bob geometry could accommodate large CRM particles and provide similar results for Superpave as well as MSCR testing.
A Case of 'Over-Cropping': Causes and Consequences of Qing Dynasty Approval to Plough and Plant the Inner Mongolian Grasslands
Authors: Geng Xiaoming , Gao Guorong
Published: December 2012

Significant grassland degradation in Inner Mongolia is generally attributed by Chinese officials and scholars to overgrazing, whereas the effects of opening up grassland for farming, or what might be considered as 'over-cropping', are overlooked. We explore this issue from a historical perspective, and focus on ploughing-up and cultivation activities promoted by the Qing Dynasty (1644-1911) during its last years, from 1902 to 1908. Crop expansion during that short period created profound social and ecological transformations in Inner Mongolia, and can be considered as marking the start of (a) agricultural dominance over herding, and (b) large-scale grassland degradation in the region during the twentieth century. This study indicates that over-cropping was a significant factor in reported grassland degradation in Inner Mongolia.
Climate Variability, Change of Land Use and Vulnerability in Pastoral Society: A Case from Inner Mongolia
Authors: Wang Xiaoyi , Zhang Qian
Published: December 2012

Climate variability is a primary characteristic of arid and semi-arid areas where drought occurs frequently. As a disaster, drought is the result of both low precipitation and social factors. If the institutions governing grassland use fail to deal with drought, grassland degradation and herder poverty will result. Based on a case study conducted in Hexigten Banner of eastern Inner Mongolia, we found that drought impacts caused by climate variability were aggravated by resource use conflicts. A series of social and economic changes in pastoral societies, including grassland segmentation, sedentarization, increased buying-in of fodder, decrease in cooperation amongst herders, and industrial development, have made herders more vulnerable to drought. Less fodder production, increased costs, and heavy debt within a disrupted community make a herder's life unsustainable. The paper points out that changes driven by policy makers may aggravate herders' vulnerability and that an alternative approach of adaptation should be developed.
The Dilemma of Conserving Rangeland by Means of Development: Exploring Ecological Resettlement in a Pastoral Township of Inner Mongolia
Authors: Zhang Qian
Published: December 2012

In the last decade environmental policies, particularly ecological resettlement, have changed China's pastoral areas. This paper explores the difficulty in conserving rangeland through ecological resettlement. The paper focuses on how ecological resettlement policy has been translated into practice, and how the affected people responded with migration decisions. Empirical findings in a pastoral township in Inner Mongolia demonstrate that local politicians have used the projects to stress economic restructuring, promotion of non-farming activities and urbanization. Meanwhile, affected households have used migration strategies to adapt to the changing economic and social environments rather than the changing natural environment. The difficulty of conserving rangelands and the marginalization of environmental concerns is a result of locally defined modernization development interests and the affected households' adaptive behaviours.
Ecological Resettlement of Tibetan Herders in the Sanjiangyuan: A Case Study in Madoi County of Qinghai
Authors: Du Fachun
Published: December 2012

Ecological resettlement (shengtai yimin in Chinese) has been initiated by the Chinese government on a large scale and aims to help degraded landscapes to recover and to improve the living standards of local people in western China. Since 2003, the government has invested RMB 7.5 billion (Chinese yuan, over U.S.$1 billion) in Qinghai Province to establish the world's second-largest nature reserve around the headwaters of the Yangtze, the Yellow and the Mekong rivers (Sanjiangyuan). The resettlement of Tibetan herders from the Sanjiangyuan grasslands to urban areas is one of the project activities. Resettlement and the grazing ban policy are understood to have profound implications for those being resettled, as well as for their home and host areas. In particular, its rationale and consequences need rethinking, from both an ecological and socio-economic perspective. This article draws on field research and a case study in Madoi County to argue the logic for resettlement, to examine its socio-economic consequences and environmental effects, and to explore possible solutions.
Lysophosphatidylcholine Acyltransferase 3 Is the Key Enzyme for Incorporating Arachidonic Acid into Glycerophospholipids during Adipocyte Differentiation
Authors: Eto Miki , Shindou Hideo , Koeberle Andreas , Harayama Takeshi , Yanagida Keisuke , Shimizu Takao
Published: December 2012

Cellular membranes contain glycerophospholipids, which have important structural and functional roles in cells. Glycerophospholipids are first formed in the de novo pathway (Kennedy pathway) and are matured in the remodeling pathway (Lands’ cycle). Recently, lysophospholipid acyltransferases functioning in Lands’ cycle were identified and characterized. Several enzymes involved in glycerophospholipid biosynthesis have been reported to have important roles in adipocytes. However, the role of Lands’ cycle in adipogenesis has not yet been reported. Using C3H10T1/2, a cell line capable of differentiating to adipocyte-like cells in vitro, changes of lysophospholipid acyltransferase activities were investigated. Lysophosphatidylcholine acyltransferase (LPCAT), lysophosphatidylethanolamine acyltransferase (LPEAT) and lysophosphatidylserine acyltransferase (LPSAT) activities were enhanced, especially with 18:2-CoA and 20:4-CoA as donors. Correspondingly, mRNA expression of LPCAT3, which possesses LPCAT, LPEAT and LPSAT activities with high specificity for 18:2- and 20:4-CoA, was upregulated during adipogenesis. Analysis of acyl-chain compositions of phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylserine (PS) showed a change in their profiles between preadipocytes and adipocytes, including an increase in the percentage of arachidonic acid-containing phospholipids. These changes are consistent with the activities of LPCAT3. Therefore, it is possible that enhanced phospholipid remodeling by LPCAT3 may be associated with adipocyte differentiation.
Oxidative Stress in Malaria
Authors: Percário Sandro , Moreira Danilo , Gomes Bruno , Ferreira Michelli , Gonçalves Ana , Laurindo Paula , Vilhena Thyago , Dolabela Maria , Green Michael
Published: December 2012

Malaria is a significant public health problem in more than 100 countries and causes an estimated 200 million new infections every year. Despite the significant effort to eradicate this dangerous disease, lack of complete knowledge of its physiopathology compromises the success in this enterprise. In this paper we review oxidative stress mechanisms involved in the disease and discuss the potential benefits of antioxidant supplementation as an adjuvant antimalarial strategy.
Characterization of in Vitro Modified Human Very Low-Density Lipoprotein Particles and Phospholipids by Capillary Electrophoresis
Authors: Liu Yi-Ning , Shu Ting-Yu , Xie Huai-Guang , Lai Wei-Ting , Liao Yi-Han , Su Mei-Yu , Lin You-Sian , Chen Yen-Yi , Lin Yi-Jyun , Chong Chin-Pong , Liu Mine-Yine
Published: December 2012

A simple capillary zone electrophoresis (CZE) method was used to characterize human very low-density lipoprotein (VLDL) particles for four healthy donors. One major peak was observed for native, in vitro oxidized and glycated VLDL particles. The effective mobilities and peak areas of the capillary electrophoresis (CE) profiles showed good reproducibility and precision. The mobility of the oxidized VLDL peak was higher than that of the native VLDL. The mobility of the glycated VLDL peak was similar to that of the native VLDL. Phospholipids isolated from VLDL particles were analyzed by our recently developed micellar electrokinetic chromatography (MEKC) with a high-salt stacking method. At absorbance 200 nm, the native VLDL phospholipids showed a major peak and a minor peak for each donor. For oxidized VLDL phospholipids, the area of the major peak reduced for three donors, possibly due to phospholipid decomposition. For glycated VLDL phospholipids, the peak mobilities were more positive than native VLDL phospholipids for two donors, possibly due to phospholipid-linked advanced glycation end products (AGEs). Very interestingly, at absorbance 234 nm, the major peak of oxidized VLDL phospholipids was resolved as two peaks for each donor, possibly due to conjugated dienes formed upon oxidation.
Climate-Driven or Human-Induced: Indicating Severe Water Scarcity in the Moulouya River Basin (Morocco)
Authors: Tekken Vera , Kropp Jürgen
Published: December 2012

Many agriculture-based economies are increasingly under stress from climate change and socio-economic pressures. The excessive exploitation of natural resources still represents the standard procedure to achieve socio-economic development. In the area of the Moulouya river basin, Morocco, natural water availability represents a key resource for all economic activities. Agriculture represents the most important sector, and frequently occurring water deficits are aggravated by climate change. On the basis of historical trends taken from CRU TS 2.1, this paper analyses the impact of climate change on the per capita water availability under inclusion of population trends. The Climatic Water Balance (CWB) shows a significant decrease for the winter period, causing adverse effects for the main agricultural season. Further, moisture losses due to increasing evapotranspiration rates indicate problems for the annual water budget and groundwater recharge. The per capita blue water availability falls below a minimum threshold of 500 m3 per year, denoting a high regional vulnerability to increasing water scarcity assuming a no-response scenario. Regional development focusing on the water-intense sectors of agriculture and tourism appears to be at risk. Institutional capacities and policies need to address the problem, and the prompt implementation of innovative water production and efficiency measures is recommended.
Videolaparoscopic Catheter Placement Reduces Contraindications to Peritoneal Dialysis
Authors: Santarelli Stefano , Zeiler Matthias , Monteburini Tania , Agostinelli Rosa Maria , Marinelli Rita , Degano Giorgio , Ceraudo Emilio
Published: December 2012

Background

Videolaparoscopy is considered the reference method for peritoneal catheter placement in patients with previous abdominal surgery. The placement procedure is usually performed with at least two access sites: one for the catheter and the second for the laparoscope. Here, we describe a new one-port laparoscopic procedure that uses only one abdominal access site in patients not eligible for laparotomic catheter placement.

Method

We carried out one-port laparoscopic placement in 21 patients presenting contraindications to blind surgical procedures because of prior abdominal surgery. This technique consists in the creation of a single mini-laparotomy access through which laparoscopic procedures and placement are performed. The catheter, rectified by an introducer, is inserted inside the port. Subsequently, the port is removed, leaving the catheter in pelvic position. The port is reintroduced laterally to the catheter, confirming or correcting its position. Laparotomic placement was performed in a contemporary group of 32 patients without contraindications to blind placement. Complications and long-term catheter outcome in the two groups were evaluated.

Results

Additional interventions during placement were necessary in 12 patients of the laparoscopy group compared with 5 patients of the laparotomy group ( p = 0.002). Laparoscopy documented adhesions in 13 patients, with need for adhesiolysis in 6 patients. Each group had 1 intra-operative complication: leakage in the laparoscopy group, and intestinal perforation in the laparotomy group. During the 2-year follow-up period, laparoscopic revisions had to be performed in 6 patients of the laparoscopy group and in 5 patients of the laparotomy group ( p = 0.26). The 1-year catheter survival was similar in both groups. Laparoscopy increased by 40% the number of patients eligible to receive peritoneal dialysis.

Conclusions

Videolaparoscopy placement in patients not eligible for blind surgical procedures seems to be equivalent to laparotomic placement with regard to complications and long-term catheter outcome. The number of patients able to receive peritoneal dialysis is substantially increased.
The Enabling Environment: Global Guidelines and National Policies for Indoor Air Quality
Authors: Elledge Myles
Published: December 2012

Indoor air pollution from biomass cooking is a significant contributor to the global burden of disease. To date there is a lack of global guidance on household energy use and health, and there are few national-scale cookstove programs. Where large-scale programming has existed, national cookstove programs have placed emphasis on energy and environment as the most common rationale for these national initiatives. The health dimension of the cookstoves issue has been underrepresented even though indoor air pollution concentrations in developing countries are known to be far above existing World Health Organization air quality guidelines. New global guidelines linking health risks and household energy use are important to drive national indoor air quality policies and cookstove interventions to place a higher priority on addressing health dimensions and to deliver broader co-benefits.