bluuebunny/crossref_metadata_2025 huggingface dataset:
Visualization Analysis of Resin Flow Behavior around a Flow Front Using a Rotary Runner Exchange System
Authors: Kanetoh Y. , Yokoi H.
Published: June 2012

In plastic injection molding, external defects such as flow marks are serious problems. These external defects are known to occur during cavity filling processes inside the mold, and are closely related to resin flow behavior in the flow front area. In this study, the authors propose a new method for visualizing in-mold resin flow behavior using a glass-inserted mold and rotary runner exchange system capable of instantaneously switching two types of melt at the runner just before the gate. This method is capable not only of dynamic visualization, but also static visualization by the observation of cross-sections of a sample, because colored resins switched multiple times at the gate spread in layers inside the sample and freeze. Using this method and general purpose polystyrene, visualization analysis of the flow behavior of inner layer resins near the flow front in simple rectangular cavities was carried out. As a result, it was found that resins reaching the flow front are not exposed at the molded product surface immediately after the fountain-flow process, but remain along the circumference of the flow front for a long period of time, and then stretch out into a thin film-like shape to form the surface of the molded product. In addition, the inner layer resins near the flow front form a converging flow just before reaching the flow front and then form a fountain flow. It was also confirmed that this is a general phenomenon in the fountain-flow process during injection molding regardless of whether the resin is crystalline or noncrystalline. Based on these results, we built a model on the flow of inner layer resins near the flow front of general resins.
Influence of the Calendering Step on the Adhesion Properties of Coextruded Structures
Authors: Serrat M. C. , Agassant J. F. , Bikard J. , Devisme S.
Published: June 2012

The coupled coextrusion calendering process of multilayer thermoplastic sheets has been studied. The structure of the film has been observed, the density of chemical links at the interface and the adhesion between the coextruded layers have been measured. There are some controversial features about the influence of calendering parameters. Several models of increasing complexity are proposed to master the process and its influence on adhesion. A multilayer thermal model accounting for the crystallization kinetics of both polymers allows defining qualitatively the temperature field especially at the interface between the two layers. A multilayer thermo-mechanical model provides quantitative figures on the stress, shear, elongation and temperature fields in the coextruded film and especially at the interface. Relationships between these parameters, density of chemical links at the interface, crystalline structure of the sample and peeling forces are discussed.
The Effect of Silane Treated Hybrid Filler on the Mechanical and Thermal Performance of Carboxylated Nitrile Butadiene Rubber (XNBR) Composites
Authors: Mousa A. , Heinrich G. , Wagenknecht U.
Published: June 2012

Carboxylated Nitrile Butadiene Rubber (XNBR) was reinforced with untreated and silane treated hybrid filler. The hybrid filler was composed of organic layered nanosilicates (NLS) and agro polymer based olive husk powder (OHP). The fabricated composites were inspected with regard to their mechanical and thermal properties. It was found that the silane treated hybrid filler was able to improve the tensile strength at break and the tensile modulus as compared to the control. The overall degree of interaction between the matrix and both the untreated and treated hybrid filler was improved. This was evidenced by the increased degree of curing which is the torque difference (τmax–τmin) derived from the moving die rheometer (MDR) and the decreased swelling index data. Dynamic mechanical analysis (DMA) revealed that the apparent was the highest in case of the silane treated hybrid filler. The thermogravimetric analysis (TGA) revealed that the thermal stability of the composites improved with the incorporation of the hybrid filler. The attenuated total reflectance (ATR-IR) revealed that dipole-dipole interactions between the various reactive functional groups namely the carboxylic of the XNBR, the hydroxyl group of the agro-polymer and the silanol of the silane agent occurred during the fabrication stage of the composites. Scanning electron microscopy (SEM) showed that the fracture surface of the samples differ after the incorporation of the treated hybrid filler.
Bi-axially Oriented Blown Film Technology
Authors: Carneiro O. S. , Covas J. A. , Domingues C.
Published: June 2012

A set of commercial polyethylenes (three LDPE and three LLDPE) was rheological characterized and processed in a laboratory double bubble extrusion line with the purpose of investigating: i) whether their relative processability could be predicted in the laboratory and ii) the effect of operating and machine variables on processability. Oscillatory shear and extensional measurements were able to differentiate the various materials, who also behaved quite differently upon processing. Those with a stronger shear thinning behaviour, higher elasticity and higher melt strength were the most suited to the process. Bubble stability and thickness uniformity were assumed as the main requirements for processability. The former was estimated by monitoring the time required to stabilize the bubble and examining any variation/oscillation in size/shape. Bubble stability depends on the interaction between various parameters, the most relevant being those related with the film cooling stage, namely the axial position of the air rings, the air flow rate and air velocity. The study was preceded by an assessment of the performance of the re-heating oven and die/calibration/centring, as these parameters could also narrow the practical operating window.
Effect of Blend Ratio of h-LLDPE and LDPE on Tear Properties of Blown Films
Authors: Mezghani K. , Furquan S. , Tabatabaei S. H. , Ajji A.
Published: June 2012

In the present study, blown films of h-LLDPE, LDPE, and their blends were produced using a twin screw extruder. The tear properties of all films were determined in the machine direction (MD) and the transverse direction (TD). On one hand, similar values of the MD tear-resistance for the two virgin polymers, h-LLDPE and LDPE, were measured to be 100 and 120 kN/m, respectively. On the other hand, the TD tear-resistance value of h-LLDPE was 180 kN/m, four times higher than that of LDPE, 45 kN/m. It was observed that small additions of LDPE (5 to 20 wt.%) to h-LLDPE produced blends with better TD tear-resistance films, 400 kN/m. The main reason for this large increase in tear-resistance was attributed to the morphological changes induced by the addition of the LDPE polymer, as shown by SEM, FTIR, and birefringence techniques.
Diffuse intrinsic pontine tumors: a study of primitive neuroectodermal tumors versus the more common diffuse intrinsic pontine gliomas
Authors: Sufit Alexandra , Donson Andrew M. , Birks Diane K. , Knipstein Jeffrey A. , Fenton Laura Z. , Jedlicka Paul , Hankinson Todd C. , Handler Michael H. , Foreman Nicholas K.
Published: June 2012

Object

The diagnosis of diffuse pontine tumors has largely been made on the basis of MRI since the early 1990s. In cases of tumors considered “typical,” as a rule, no biopsy specimen has been obtained, and the tumors have been considered diffuse intrinsic pontine gliomas (DIPGs). There have been sporadic reports that primitive neuroectodermal tumors (PNETs) of the pons may not be distinguishable from the DIPGs by radiological imaging. This study presents 2 cases of diffuse pontine PNETs with molecular evidence that these are indeed PNETs, distinct from DIPGs, thus supporting biopsy of diffuse pontine tumors as a standard of care.

Methods

Biopsy specimens were obtained from 7 diffuse pontine tumors and snap frozen. Two of these 7 tumors were identified on the basis of pathological examination as PNETs. All 7 of the diffuse pontine tumors were analyzed for gene expression using the Affymetrix HG-U133 Plus 2.0 GeneChip microarray. Gene expression was compared with that of supratentorial PNETs, medulloblastomas, and low- and high-grade gliomas outside the brainstem.

Results

Unsupervised hierarchical clustering analysis of gene expression demonstrated that pontine PNETs are most closely related to PNETs of the supratentorial region and not with gliomas. They do not cluster with the 5 DIPGs in the study. Thirty-eight genes, including GATA3, are uniquely differentially expressed in pontine PNETs compared with other types of pediatric brain tumors, including DIPGs and other PNETs at a false discovery rate statistical significance of less than 0.05.

Conclusions

The cluster and individual gene expression analyses indicate that pontine PNETs are intrinsically different from DIPGs. The 2 pontine PNET cases cluster with supratentorial PNETs, rather than with DIPGs, suggesting that these tumors should be treated with a PNET regimen, not with DIPG therapy. Since diagnosis by imaging is not reliable and the biology of the tumors is disparate, a biopsy should be performed to enable accurate diagnosis and direct potentially more effective treatments.
Comparative effectiveness research: policy and politics
Authors: Zusman Edie E.
Published: June 2012

Comparative effectiveness research (CER) is the basis for some of the fiercest rhetoric of the current political era. While it is a relatively old and previously academic pursuit, CER may well become the foundation upon which the future of health care in the US is based.

The actual impact of CER on—and uptake among—doctors, patients, hospitals, and health insurers, however, remains to be seen. Political considerations and compromises have led to the removal of key aspects of CER implementation from policy legislation to prevent alienating stakeholders critical to the success of health care reform.

Health care providers, including specialists such as neurosurgeons, will need to understand both the policies and political implications of CER as its practices becomes an indelible part of the future health care landscape.
Long-term outcome for endoscopic third ventriculostomy alone or in combination with choroid plexus cauterization for congenital aqueductal stenosis in African infants
Authors: Warf Benjamin C. , Tracy Sarah , Mugamba John
Published: June 2012

Object

The authors have previously reported on the overall improved efficacy of endoscopic third ventriculostomy (ETV) combined with choroid plexus cauterization (CPC) for infants younger than 1 year of age. In the present study they specifically examined the long-term efficacy of ETV with or without CPC in 35 infants with congenital aqueduct stenosis treated at CURE Children's Hospital of Uganda during the years 2001–2006.

Methods

Infants with congenital aqueductal stenosis were treated during 2 distinct treatment epochs: all underwent ETV alone, and subsequently all underwent ETV-CPC. Prospectively collected data in the clinical database were reviewed for all infants with an age < 1 year who had been treated for hydrocephalus due to congenital aqueductal stenosis. Study exclusion criteria included: 1) a history or findings on imaging or at the time of ventriculoscopy that suggested a possible infectious cause of the hydrocephalus, including scarred choroid plexus; 2) an open aqueduct or an aqueduct obstructed by a membrane or cyst rather than by stenosis; 3) severe malformations of the cerebral hemispheres including hydranencephaly, significant segments of undeveloped brain, or schizencephaly; 4) myelomeningocele, encephalocele, Dandy-Walker complex, or tumor; or 5) previous shunt insertion. The time to treatment failure was analyzed using the Kaplan-Meier method to construct survival curves. Log-rank (Mantel-Cox) and Gehan-Breslow-Wilcoxon tests were used to determine whether differences between the 2 treatment groups were significant.

Results

Thirty-five patients met the study criteria. Endoscopic third ventriculostomy alone was performed in 12 patients (mean age 4.7 months), and combined ETV-CPC was performed in 23 patients (mean age 3.5 months). For patients without treatment failure, the mean and median follow-ups were, respectively, 51.6 and 48.0 months in the ETV group and 31.2 and 26.4 months in the ETV-CPC group. Treatment was successful in 48.6% of the patients who underwent ETV alone, as accurately predicted by the Endoscopic Third Ventriculostomy Success Score (ETVSS), and in 81.9% of the patients who underwent ETV-CPC (p = 0.0119, log-rank test; p = 0.0041, Gehan-Breslow-Wilcoxon test; HR 6.42 [95% CI 1.51–27.36]).

Conclusions

Combined ETV-CPC is significantly superior to ETV alone for infants younger than 1 year of age with congenital aqueductal stenosis. The fact that the outcome for ETV alone was accurately predicted by the ETVSS suggests that these results are applicable in developed countries.
A novel tissue engineering approach using an endothelial progenitor cell–seeded biopolymer to treat intracranial saccular aneurysms
Authors: Aronson Joshua P. , Mitha Alim P. , Hoh Brian L. , Auluck Pavan K. , Pomerantseva Irina , Vacanti Joseph P. , Ogilvy Christopher S.
Published: June 2012

Object

Recurrence after endovascular coiling of intracranial aneurysms is reported in up to 42% of cases and is attributed to the lack of endothelialization across the neck. In this study the authors used a novel tissue engineering approach to promote endothelialization by seeding endothelial progenitor cells (EPCs) within a fibrin polymer injected endovascularly into the aneurysm.

Methods

Experimental aneurysms were created in New Zealand White rabbits and were left untreated, surgically clipped, or embolized with platinum coils, fibrin biopolymer alone, or fibrin combined with autologous cultured EPCs.

Results

In aneurysms treated with EPCs, a confluent monolayer of endothelial cells with underlying neointima was demonstrated across the neck at 16 weeks posttreatment, which was not observed with aneurysms treated using the other methods.

Conclusions

This novel technique may address reasons for the limited durability of standard coil embolization and provides further avenues for the development of improved devices for the care of patients with aneurysms.
Effects of aging on behavioral assessment performance: implications for clinically relevant models of neurological disease
Authors: Turner Ryan C. , Seminerio Michael J. , Naser Zachary J. , Ford J. Neal , Martin Samantha J. , Matsumoto Rae R. , Rosen Charles L. , Huber Jason D.
Published: June 2012

Object

Despite the role of aging in development of neurological and neurodegenerative diseases, the effects of age are often disregarded in experimental design of preclinical studies. Functional assessment increases the clinical relevance of animal models of neurological disease and adds value beyond traditional histological measures. However, the relationship between age and functional impairment has not been systematically assessed through a battery of functional tests.

Methods

In this study, various sensorimotor and behavioral tests were used to evaluate effects of aging on functional performance in naive animals. Sensorimotor measures included locomotor activity; Rotarod, inclined plane, and grip-strength testing; and modified Neurological Severity Score. The Morris water maze was used to examine differences in learning and memory, and the elevated plus maze and forced swim test were used to assess anxiety-like and depressive-like behaviors, respectively.

Results

Older Sprague-Dawley rats (18–20 months) were found to perform significantly worse on the inclined plane tests, and they exhibited alterations in elevated-plus maze and forced swim test compared with young adult rats (3–4 months). Specifically, older rats exhibited reduced exploration of open arms in elevated plus maze and higher immobility time in forced swim test. Spatial acquisition and reference memory were diminished in older rats compared with those in young adult rats.

Conclusions

This study demonstrates clear differences between naive young adult and older animals, which may have implications in functional assessment for preclinical models of neurological disease.
Evaluating the Marginal Land Resources Suitable for Developing Pistacia chinensis-Based Biodiesel in China
Authors: Lu Lu , Jiang Dong , Zhuang Dafang , Huang Yaohuan
Published: June 2012

Bio-energy from energy plants is expected to play an increasing role in the future energy system, with benefits in terms of reducing greenhouse gas emissions and improving energy security. Pistacia chinensis is believed to be one of the most promising non-food input for biodiesel production. This study focused on the marginal land availability for developing Pistacia chinensis-based bioenergy in China. The spatial distribution, quality and total amount of marginal land resources suitable for cultivating Pistacia chinensis were identified with multiple datasets (natural habitat, remote sensing-derived land use, meteorological and soil data) and geoinformatic techniques. The results indicate that the area of marginal land exploitable for Pistacia chinensis plantations in China is 19.90 million hectares, which may produce approximately 56.85 million tons of biodiesel each year. The spatial variation of both marginal land resources and biodiesel potential are also presented. The results can be useful for national and regional bio-energy planning.
Effects of Cold Air on Cardiovascular Disease Risk Factors in Rat
Authors: Luo Bin , Zhang Shuyu , Ma Shoucun , Zhou Ji , Wang Baojian
Published: June 2012

The purpose of this study is to explore possible potential implications of cold air in cardiovascular disease (CVD) risk in rats. Healthy Wistar rats were exposed to artificial cold air under laboratory conditions, and their systolic blood pressure, heart rate, vasoconstriction, CVD risk factors, and myocardial damage indicators after cold air exposure were determined and evaluated. Systolic blood pressure, whole blood viscosity, and plasma level of norepinephrine, angiotensinⅡ, low density lipoprotein, total cholesterol, and fibrinogen in treatment groups increased significantly compared with control groups. No significant variations were found in plasma Mb and cTnT and myocardial tissue between the treatment and control groups. Results indicate that: (1) higher levels of SBP, WBV and LDL/HDL, total cholesterol (TC), and FG in blood may indicate higher CVD risks during cold air exposure; (2) cold air may exert continuous impacts on SBP and other CVD risk factors.
Elongation Factor 1β' Gene from Spodoptera exigua: Characterization and Function Identification through RNA Interference
Authors: Zhao Li-Na , Qin Zi , Wei Ping , Guo Hong-Shuang , Dang Xiang-Li , Wang Shi-Gui , Tang Bin
Published: June 2012

Elongation factor (EF) is a key regulation factor for translation in many organisms, including plants, bacteria, fungi, animals and insects. To investigate the nature and function of elongation factor 1β' from Spodoptera exigua (SeEF-1β'), its cDNA was cloned. This contained an open reading frame of 672 nucleotides encoding a protein of 223 amino acids with a predicted molecular weight of 24.04 kDa and pI of 4.53. Northern blotting revealed that SeEF-1β' mRNA is expressed in brain, epidermis, fat body, midgut, Malpighian tubules, ovary and tracheae. RT-PCR revealed that SeEF-1β' mRNA is expressed at different levels in fat body and whole body during different developmental stages. In RNAi experiments, the survival rate of insects injected with SeEF-1β' dsRNA was 58.7% at 36 h after injection, which was significantly lower than three control groups. Other elongation factors and transcription factors were also influenced when EF-1β' was suppressed. The results demonstrate that SeEF-1β' is a key gene in transcription in S. exigua.
The Genus Caesalpinia L. (Caesalpiniaceae): Phytochemical and Pharmacological Characteristics
Authors: Zanin João L. Baldim , De Carvalho Bianca A. , Salles Martineli Paloma , Dos Santos Marcelo Henrique , Lago João Henrique G. , Sartorelli Patrícia , Viegas Cláudio , Soares Marisi G.
Published: June 2012

The genus Caesalpinia (Caesalpiniaceae) has more than 500 species, many of which have not yet been investigated for potential pharmacological activity. Several classes of chemical compounds, such as flavonoids, diterpenes, and steroids, have been isolated from various species of the genus Caesalpinia. It has been reported in the literature that these species exhibit a wide range of pharmacological properties, including antiulcer, anticancer, antidiabetic, anti-inflammatory, antimicrobial, and antirheumatic activities that have proven to be efficacious in ethnomedicinal practices. In this review we present chemical and pharmacological data from recent phytochemical studies on various plants of the genus Caesalpinia.
Simultaneous Quantification of Five Bioactive Components of Acanthopanax senticosus and Its Extract by Ultra Performance Liquid Chromatography with Electrospray Ionization Time-of-Flight Mass Spectrometry
Authors: Liu Shi-Ping , An Jing-Tao , Wang Rui , Li Qiang
Published: June 2012

A simple and reliable ultra performance liquid chromatography coupled with electrospray ionization time-of-flight mass spectrometry method (UPLC-TOF-MS) was developed and validated for the simultaneous determination of the major bioactive constituents in Acanthopanax senticosus and its extract. The separation of five compounds was performed on a UPLCTM HSS T3 column (100 mm × 2.1 mm, 1.7 μm) with gradient elution using a mobile phase consisting of 0.1% aqueous formic acid and acetonitrile containing 0.1% formic acid. All targeted compounds (syringin, chlorogenid acid, caffeic acid, eleutheroside E and isofraxidin) were baseline separated within 5.3 min in samples, which represented an approximate six-fold reduction in the analysis time in comparison to published HPLC method. Quantitation was carried out working in the V mode using the narrow widow extracted ion chromatograms (nwXICs) of each compound (extracted using a 20 mDa window). Furthermore, all calibration curves showed good linearity (r > 0.999) within the test ranges. The precision was evaluated by intra- and inter-day tests, which revealed relative standard deviation (RSD) values of less than 3.88%. The recoveries for the quantified compounds were between 96.3% and 103.7%, with RSD values below 2.89%. According to the literature, this study represents the first investigation of the simultaneous analysis of multiple components and the method can be applied to determine the amounts of the major compounds in Acanthopanax senticosus and its extract by UPLC-TOF-MS.
Development and Validation of a Successful Microbiological Agar Assay for Determination of Ceftriaxone Sodium in Powder for Injectable Solution
Authors: Aléssio Patrícia V. , Salgado Hérida R. N.
Published: June 2012

Ceftriaxone sodium is a cephalosporin with broad-spectrum antimicrobial activity and belongs to the third generation of cephalosporins. Regarding the quality control of medicines, a validated microbiological assay for the determination of ceftriaxone sodium in powder for injectable solution has not been reported yet. This paper reports the development and validation of a simple, accurate and reproducible agar diffusion method to quantify ceftriaxone sodium in powder for injectable solution. The assay is based on the inhibitory effect of ceftriaxone sodium on the strain of Bacillus subtilis ATCC 9371 IAL 1027 used as test microorganism. The results were treated statistically by analysis of variance and were found to be linear (r = 0.999) in the selected range of 15.0–60.0 μg/mL, precise with a relative standard deviation (RSD) of repeatability intraday = 1.40%, accurate (100.46%) and robust with a RSD lower than 1.28%. The results demonstrated the validity of the proposed bioassay, which allows reliable ceftriaxone sodium quantitation in pharmaceutical samples and therefore can be used as a useful alternative methodology for the routine quality control of this medicine.
High Resolution Mapping of Peatland Hydroperiod at a High-Latitude Swedish Mire
Authors: Torbick Nathan , Persson Andreas , Olefeldt David , Frolking Steve , Salas William , Hagen Stephen , Crill Patrick , Li Changsheng
Published: June 2012

Monitoring high latitude wetlands is required to understand feedbacks between terrestrial carbon pools and climate change. Hydrological variability is a key factor driving biogeochemical processes in these ecosystems and effective assessment tools are critical for accurate characterization of surface hydrology, soil moisture, and water table fluctuations. Operational satellite platforms provide opportunities to systematically monitor hydrological variability in high latitude wetlands. The objective of this research application was to integrate high temporal frequency Synthetic Aperture Radar (SAR) and high spatial resolution Light Detection and Ranging (LiDAR) observations to assess hydroperiod at a mire in northern Sweden. Geostatistical and polarimetric (PLR) techniques were applied to determine spatial structure of the wetland and imagery at respective scales (0.5 m to 25 m). Variogram, spatial regression, and decomposition approaches characterized the sensitivity of the two platforms (SAR and LiDAR) to wetland hydrogeomorphology, scattering mechanisms, and data interrelationships. A Classification and Regression Tree (CART), based on random forest, fused multi-mode (fine-beam single, dual, quad pol) Phased Array L-band Synthetic Aperture Radar (PALSAR) and LiDAR-derived elevation to effectively map hydroperiod attributes at the Swedish mire across an aggregated warm season (May–September, 2006–2010). Image derived estimates of water and peat moisture were sensitive (R2 = 0.86) to field measurements of water table depth (cm). Peat areas that are underlain by permafrost were observed as areas with fluctuating soil moisture and water table changes.
Study Designs and Statistical Analyses for Biomarker Research
Authors: Gosho Masahiko , Nagashima Kengo , Sato Yasunori
Published: June 2012

Biomarkers are becoming increasingly important for streamlining drug discovery and development. In addition, biomarkers are widely expected to be used as a tool for disease diagnosis, personalized medication, and surrogate endpoints in clinical research. In this paper, we highlight several important aspects related to study design and statistical analysis for clinical research incorporating biomarkers. We describe the typical and current study designs for exploring, detecting, and utilizing biomarkers. Furthermore, we introduce statistical issues such as confounding and multiplicity for statistical tests in biomarker research.
Material Footprint of Low-Income Households in Finland—Consequences for the Sustainability Debate
Authors: Lettenmeier Michael , Hirvilammi Tuuli , Laakso Senja , Lähteenoja Satu , Aalto Kristiina
Published: June 2012

The article assesses the material footprints of households living on a minimum amount of social benefits in Finland and discusses the consequences in terms of ecological and social sustainability. The data were collected using interviews and a questionnaire on the consumption patterns of 18 single households. The results are compared to a study on households with varying income levels, to average consumption patterns and to decent minimum reference budgets. The low-income households have lower material footprints than average and most of the material footprints are below the socially sustainable level of consumption, which is based on decent minimum reference budgets. However, the amount of resources used by most of the households studied here is still at least double that required for ecological sustainability. The simultaneous existence of both deprivation and overconsumption requires measures from both politicians and companies to make consumption sustainable. For example, both adequate housing and economic mobility need to be addressed. Measures to improve the social sustainability of low-income households should target reducing the material footprints of more affluent households. Furthermore, the concept of what constitutes a decent life should be understood more universally than on the basis of standards of material consumption.
Molecular Identification of Chronic Bee Paralysis Virus Infection in Apis mellifera Colonies in Japan
Authors: Morimoto Tomomi , Kojima Yuriko , Yoshiyama Mikio , Kimura Kiyoshi , Yang Bu , Kadowaki Tatsuhiko
Published: June 2012

Chronic bee paralysis virus (CBPV) infection causes chronic paralysis and loss of workers in honey bee colonies around the world. Although CBPV shows a worldwide distribution, it had not been molecularly detected in Japan. Our investigation of Apis mellifera and Apis cerana japonica colonies with RT-PCR has revealed CBPV infection in A. mellifera but not A. c. japonica colonies in Japan. The prevalence of CBPV is low compared with that of other viruses: deformed wing virus (DWV), black queen cell virus (BQCV), Israel acute paralysis virus (IAPV), and sac brood virus (SBV), previously reported in Japan. Because of its low prevalence (5.6%) in A. mellifera colonies, the incidence of colony losses by CBPV infection must be sporadic in Japan. The presence of the (−) strand RNA in dying workers suggests that CBPV infection and replication may contribute to their symptoms. Phylogenetic analysis demonstrates a geographic separation of Japanese isolates from European, Uruguayan, and mainland US isolates. The lack of major exchange of honey bees between Europe/mainland US and Japan for the recent 26 years (1985–2010) may have resulted in the geographic separation of Japanese CBPV isolates.
ESTIMATING CAPITAL AND OPERATIONAL COSTS OF BACKHOE SHOVELS
Authors: Sayadi Ahmad Reza , Lashgari Ali , Fouladgar Mohammad Majid , Skibniewski Miroslaw J.
Published: June 2012

Material loading is one of the most critical operations in earthmoving projects. A number of different equipment is available for loading operations. Project managers should consider different technical and economic issues at the feasibility study stage and try to select the optimum type and size of equipment fleet, regarding the production needs and project specifications. The backhoe shovel is very popular for digging, loading and flattening tasks. Adequate cost estimation is one of the most critical tasks in feasibility studies of equipment fleet selection. This paper presents two different cost models for the preliminary and detailed feasibility study stages. These models estimate the capital and operating cost of backhoe shovels using uni-variable exponential regression (UVER) as well as multi-variable linear regression (MVLR), based on principal component analysis. The UVER cost model is suitable for quick cost estimation at the early stages of project evaluation, while the MVLR cost function, which is more detailed, can be useful for the feasibility study stage. Independent variables of MVLR include bucket size, digging depth, dump height, weight and power. Model evaluations show that these functions could be a credible tool for cost estimations in prefeasibility and feasibility studies of mining and construction projects.
INFLUENCE OF DIFFERENT LOADS ON THE PROPERTIES OF LIGHTWEIGHT COMPOSITE
Authors: Kligys Modestas , Sinica Marijonas , Sezemanas Georgijus , Miškinis Kęstutis , Vaitkus Saulius
Published: June 2012

The paper describes the study on the operational properties of lightweight composite with density of 150–350 kg/m3. It was established that these properties depend on the ratio of porous cement matrix and inclusions of crushed expanded polystyrene packing tare waste per unit volume of the lightweight composite. Studies have demonstrated that when the density of lightweight composite varies in the above mentioned limits, the compressibility amounts to 2.4–0.8 mm, point load – 0.38–3.39 kN, dynamic stiffness – 35–135 MN/m3, and reduction in normalised impact sound pressure level – 26–17 dB. The dependences between the established properties and the density of lightweight composite are showed in the equations of regression. Possible versions for the use of lightweight composite in different constructions of floors and roofs are also provided.
EVALUATING ELASTIC-PLASTIC BEHAVIOUR OF ROCK MATERIALS USING HOEK–BROWN FAILURE CRITERION
Authors: Hasanzadehshooiili Hadi , Lakirouhani Ali , Medzvieckas Jurgis
Published: June 2012

As a matter of fact, the failure criteria only predict failure's initiation in materials. And, in order to predict post-yield behaviour of materials, a much complicated formulation for stress-strain relationship is required, which we know as plasticity theory. For instance, these formulations are developed based on Mohr-Coulomb criterion for soils and Drucker-Prager criterion for concrete. According to a majority of rock mechanics researchers, the empirical and experimental Hoek-Brown failure criterion is one of the well-progressed and suitable criteria, which can efficiently predict the rock failure initiation under different stress states for various types of intact rocks and rock masses. In this article, according to the suggestion by Heok explained in his paper of 1997, this rugged mentioned criterion is considered as a yield criterion and the elastic-perfect plastic behaviour of rock masses is determined using calculating material constitutive matrix's arrays in terms of Hoek-Brown's material constants and mechanical characteristics of rock materials in the general stress space, considering associated flow rule.
FACTORS AFFECTING JOB SATISFACTION OF WORKERS IN INDONESIAN CONSTRUCTION COMPANIES
Authors: Marzuki Puti Farida , Permadi Hestiyani , Sunaryo Indryati
Published: June 2012

This paper describes the influence of job characteristics, rewards, relations with superiors, relations with co-workers, and fulfillment of higher order needs, as job facets, on the job satisfaction of workers in Indonesian construction companies. A questionnaire survey was conducted in Jakarta (the capital city) and Bandung (one of Indonesia's major cities). The results revealed that workers in different occupational groups and managerial positions perceive differently the conditions of job facets and that there are different levels of job satisfaction among different categories of workers. This research indicates that workers care about the quality of their work and company's performance and that these aspects affect significantly their job satisfaction. Reward is also revealed to have an important influence on workers’ job satisfaction.
PREDICTION OF STRENGTH AND SLUMP OF RICE HUSK ASH INCORPORATED HIGH-PERFORMANCE CONCRETE
Authors: Islam Md. Nazrul , Zain Muhammad Fauzi Mohd , Jamil Maslina
Published: June 2012

This paper describes the development of statistical models to predict strength and slump of rice husk ash (RHA) incorporated high-performance concrete (HPC). Sixty samples of RHA incorporated HPC mixes having compressive strength range of 42–92 MPa and slump range of 170–245 mm were prepared and tested in the laboratory. These experimental data of sixty RHA incorporated HPC mixes were used to develop two models. Six variables namely water-to-binder ratio, cement content, RHA content, fine aggregate content, coarse aggregate content and superplasticizer content were selected to develop the models and ultimately to predict strength and slump of RHA incorporated HPC. The models were developed by regression analysis. Additional five HPC mixes were prepared with the same ingredients and tested under the same testing conditions to verify the ability of the proposed models to predict the responses. The results of the prediction of the models showed good agreement with the experimental data. Thus the developed models can be used to predict slump and 28-day compressive strength of RHA incorporated HPC. The research demonstrated that strength and slump of HPC could be successfully modeled using statistical analysis.
BENCHMARKING THE KNOWLEDGE MANAGEMENT PRACTICES OF CONSTRUCTION FIRMS
Authors: Kale Serdar , Karaman A. Erkan
Published: June 2012

Knowledge management is rapidly becoming a key organizational capability for creating competitive advantage in the construction industry. The emergence of knowledge management in this capacity poses enormous challenges to executives of construction firms. This paper proposes a model for benchmarking those knowledge management practices of AEC firms that can guide and assist construction business executives in meeting these challenges. The proposed model incorporates benchmarking and knowledge management concepts with importance-performance analysis (IPA) maps. It is a simple visual tool that can provide powerful diagnostic information to executives of AEC firms by evaluating their firm's knowledge management practices, identifying their firm's comparative advantages and disadvantages with regard to each knowledge management practice, and setting priorities for managerial actions related to knowledge management practices that need improvement. A real-world case study is presented to illustrate the implementation and utility of the proposed model.
UNCONVENTIONAL DOUBLE-LEVEL STRUCTURAL SYSTEM FOR UNDER-DECK CABLE-STAYED BRIDGES
Authors: Misiunaitė Ieva , Daniūnas Alfonsas , Juozapaitis Algirdas
Published: June 2012

This paper presents a new morphology of a cable-staying system for an under-deck cable-stayed bridge. The computational method proposed in the paper has been derived for a one-strut conventional cable staying system and applied for an unconventional double-level cable-staying system. The paper describes an algorithm for the correct implementation of the interaction between the cable-staying system and the deck. The numerical examples demonstrate that the proposed computational method based on a non-linear analysis of a simply supported and additionally restrained beam-column can be used for obtaining deformation response to the considered structure. An analysis of the same problem using finite element (FE) software ANSYS was carried out to present the accuracy of the proposed method. The paper also demonstrates comparison analysis between the conventional and unconventional structural schemes for the under-deck cable-stayed bridge under symmetric and asymmetric loading.
ACHIEVING SUSTAINABLE CONSTRUCTION WITHIN PRIVATE FINANCE INITIATIVE (PFI) ROAD PROJECTS IN THE UK
Authors: Akbiyikli Rifat , Eaton David , Umit Dikmen Seyyit
Published: June 2012

The construction industry is facing the challenge of increasing demands of its sustainability performance. The construction and maintenance of the built environment has substantial impact on the sustainability of the environment. Meanwhile, public sector clients are increasingly asking for a sustainable approach in their specification and procurement decisions, sustainability is still seen as a novel concept within the construction industry in many parts of the world without a settled definition. The premise of this study is that the interaction between road projects realized by the private finance initiative and their delivery in the UK improve sustainability. The paper, based on the case study research, explains the sustainability implementation in two PFI road projects and demonstrates that the PFI mechanism facilitates sustainable implementation to a far greater extent than is achievable using traditional procurement methods.
WHAT MOTIVATES FIRMS FROM EMERGING ECONOMIES TO GO INTERNATIONALIZATION?
Authors: Zeng Ruochen , Zeng Saixing , Xie Xuemei , Tam Chiming , Wan Tianwei
Published: June 2012

With advent of economic globalization, internationalization has become one of the most important strategies for firms to achieve sustainable growth. Based on the empirical research in the Yangtze River Delta region in China, the method of Correspondence Analysis was employed to study the motivations for going internationalization of Chinese enterprises. The main findings include: (1) the motivations for internationalization of enterprises depend on their scale, and largesized enterprises are mainly motivated by the purpose of creating global brands and enhancing domestic reputation; (2) the ownership of enterprises has obvious influence on their motivations for going internationalization, and (3) enterprises in different industries also show different levels of motivation for internationalization.
PERFORMANCE EVALUATING OF RURAL ICT CENTERS (TELECENTERS), APPLYING FUZZY AHP, SAW-G AND TOPSIS GREY, A CASE STUDY IN IRAN
Authors: Zolfani Sarfaraz Hashemkhani , Sedaghat Maedeh , Zavadskas Edmundas Kazimieras
Published: June 2012

The project of developing technology in villages was an important project in Iran which was finished in 2010 but it's still being pursued to develop its related services. This project includes many major and minor objectives. After passing six years from the beginning of this project, it seems reasonable to do research about evaluating the progress of these centers. Hence, a framework of evaluation is presented studying past researches utilizing the following criteria; public training, classic training, special training, cultural services, social services, governmental services and other services. Three MCDM methods are applied for evaluating; Fuzzy AHP is used for calculating weights of each criteria and sub-criteria and SAW-G and TOPSIS Grey are applied for evaluating alternatives. Three rural ICT centers are selected as a case study which are located in Golestan Province in north of Iran. The findings show that due to new services presented in these areas, public training and cultural services are more important criteria. Results of SAW-G and TOPSIS Grey are the same which both selected Gharnabad ICT center as the best center and Livan and Bala Jadeh centers are placed as the second and third, respectively.
GEODETIC SURVEYING STUDIES FOR CIVIL ENGINEERING STUDENTS AT TALLINN UNIVERSITY OF TECHNOLOGY
Authors: Ustinova Nelli , Kala Vello , Mill Tarvo , Ellmann Artu
Published: June 2012

Studies in the Tallinn University of Technology are based on a modular system, where geodetic surveying comprises a self-contained study module in the curricula of all civil engineering specialities. Due to geodetic surveying being taught to all first year students of civil engineering, it serves as a touchstone to test a student's suitability for an engineering specialism. Future civil engineers are taught basic geodetic measurements and how to use optical theodolite, levelling instrument and laser level. The paper gives an overview of geodetic surveying lectures, laboratory classes and field survey camp. Teaching and assessment are based on learning outcomes. Students who have passed the exam are allowed to participate in the summer field survey camp, the aim of which is consolidating the knowledge acquired throughout the year and practising teamwork.
ON GENERATING DIGITAL ELEVATION MODELS FROM LIDAR DATA – RESOLUTION VERSUS ACCURACY AND TOPOGRAPHIC WETNESS INDEX INDICES IN NORTHERN PEATLANDS
Authors: Hasan Abdulghani , Pilesjö Petter , Persson Andreas
Published: June 2012

Global change and GHG emission modelling are dependent on accurate wetness estimations for predictions of e.g. methane emissions. This study aims to quantify how the slope, drainage area and the TWI vary with the resolution of DEMs for a flat peatland area. Six DEMs with spatial resolutions from 0.5 to 90 m were interpolated with four different search radiuses. The relationship between accuracy of the DEM and the slope was tested. The LiDAR elevation data was divided into two data sets. The number of data points facilitated an evaluation dataset with data points not more than 10 mm away from the cell centre points in the interpolation dataset. The DEM was evaluated using a quantile-quantile test and the normalized median absolute deviation. It showed independence of the resolution when using the same search radius. The accuracy of the estimated elevation for different slopes was tested using the 0.5 meter DEM and it showed a higher deviation from evaluation data for steep areas. The slope estimations between resolutions showed differences with values that exceeded 50%. Drainage areas were tested for three resolutions, with coinciding evaluation points. The model ability to generate drainage area at each resolution was tested by pair wise comparison of three data subsets and showed differences of more than 50% in 25% of the evaluated points. The results show that consideration of DEM resolution is a necessity for the use of slope, drainage area and TWI data in large scale modelling.
Les enjeux industriels et commerciaux d’une participation financière : Devanlay & Recoing, actionnaire des grands magasins, 1945-1975
Authors: Baubeau Patrice
Published: June 2012

Résumé La société Devanlay, qui reste le principal opérateur industriel de la célèbre marque Lacoste, a étroitement articulé son développement industriel après-guerre avec des prises de participations dans le secteur de la distribution. Mais l’épuisement du modèle de production fordiste a fait apparaître les contradictions entre cœur industriel et participations commerciales, qu’il s’agisse du statut attribué aux marques ou du dramatique épisode de la « guerre du collant ».
Une comparaison empirique du profil des acheteurs monocanal et multicanaux
Authors: Bèzes Christophe
Published: June 2012

Résumé Cette recherche vérifie la possibilité de segmenter les canaux de distribution selon les caractéristiques personnelles des acheteurs ; elle identifie ensuite les plus prédictives de l’achat sur chaque canal. Menée sur 1 478 clients d’une enseigne multicanal, l’étude met en évidence la nécessité de réfléchir sur la gestion multicanal, non plus en termes de clients mais d’acheteurs. La distance aux points de vente ressort comme un critère majeur de segmentation, pourtant rarement mobilisé. Cette recherche montre également que les orientations d’achat d’un même individu diffèrent d’un canal à l’autre.
Comment les consommateurs perçoivent-ils la proximité à l'égard d'un circuit court alimentaire ?
Authors: Hérault-Fournier Catherine , Merle Aurélie , Prigent-Simonin Anne Hélène
Published: June 2012

Résumé Cette recherche analyse la proximité perçue par les consommateurs lors d’achats de produits alimentaires dans un type de circuit court : le point de vente collectif. Dans la continuité de Bergadaà et Del Buccia (2009) et sur la base d’études qualitative et quantitative, quatre dimensions de la proximité perçue au circuit court sont identifiées : la proximité d’accès, identitaire, relationnelle et de processus. L’influence des trois dernières dimensions sur la confiance perçue est confirmée. Enfin, l’intérêt managérial de cette approche est discuté.
Vers des Médecins-Managers-Mentors ? Premiers résultats d'un accompagnement concerté dans un CHU
Authors: Duchamp David , Persson Sybil
Published: June 2012

Résumé L’article décrit et analyse une démarche d’accompagnement concerté auprès de jeunes médecins repérés comme porteurs d’un haut potentiel au sein d’un CHU. L’accompagnement est pensé au service d’un projet de carrière à l’hôpital en prenant appui sur les relations mentorales. La discussion conduite souligne l’interaction entre les rôles de médecin et de manager en y ajoutant celui de mentor pour instaurer une dynamique intergénérationnelle efficiente et durable.
Le sujet moderne dans le coaching : une lecture à partir des travaux de Charles Taylor
Authors: Rappin Baptiste
Published: June 2012

Résumé L’article se propose de comprendre la nature du sujet moderne dans la pratique du coaching. C’est pourquoi il prend appui sur les travaux du philosophe Charles Taylor concernant la formation de l’identité moderne. Nous créons à partir de cela une typologie des dimensions de la subjectivité qui nous permet de rendre compte de l’observation d’une séance de coaching ; nous discutons alors de sa pertinence pour le coaching en général