bluuebunny/crossref_metadata_2025 huggingface dataset:
Brg-1 mediates the constitutive and fenretinide-induced expression of SPARC in mammary carcinoma cells via its interaction with transcription factor Sp1
Authors: Xu Yong Zhong , Heravi Mitra , Thuraisingam Thusanth , Marco Sergio Di , Muanza Thierry , Radzioch Danuta
Published: August 2010

Background

Secreted protein, acidic and rich in cysteine (SPARC) is a matricellular protein that mediates cell-matrix interactions. It has been shown, depending on the type of cancer, to possess either pro- or anti-tumorigenic properties. The transcriptional regulation of the SPARC gene expression has not been fully elucidated and the effects of anti-cancer drugs on this process have not been explored.

Results

In the present study, we demonstrated that chromatin remodeling factor Brg-1 is recruited to the proximal SPARC promoter region (-130/-56) through an interaction with transcription factor Sp1. We identified Brg-1 as a critical regulator for the constitutive expression levels of SPARC mRNA and protein in mammary carcinoma cell lines and for SPARC secretion into culture media. Furthermore, we found that Brg-1 cooperates with Sp1 to enhance SPARC promoter activity. Interestingly, fenretinide [N-4(hydroxyphenyl) retinamide, 4-HPR], a synthetic retinoid with anti-cancer properties, was found to up-regulate the transcription, expression and secretion of SPARC via induction of the Brg-1 in a dose-dependent manner. Finally, our results demonstrated that fenretinide-induced expression of SPARC contributes significantly to a decreased invasion of mammary carcinoma cells.

Conclusions

Overall, our results reveal a novel cooperative role of Brg-1 and Sp1 in mediating the constitutive and fenretinide-induced expression of SPARC, and provide new insights for the understanding of the anti-cancer effects of fenretinide.
Incidence of the V600K mutation among melanoma patients with BRAF mutations, and potential therapeutic response to the specific BRAF inhibitor PLX4032
Authors: Rubinstein Jill C , Sznol Mario , Pavlick Anna C , Ariyan Stephan , Cheng Elaine , Bacchiocchi Antonella , Kluger Harriet M , Narayan Deepak , Halaban Ruth
Published: August 2010

Activating mutations in BRAF kinase are common in melanomas. Clinical trials with PLX4032, the mutant-BRAF inhibitor, show promising preliminary results in patients selected for the presence of V600E mutation. However, activating V600K mutation is the other most common mutation, yet patients with this variant are currently excluded from the PLX4032 trials. Here we present evidence that a patient bearing the BRAF V600K mutation responded remarkably to PLX4032, suggesting that clinical trials should include all patients with activating BRAF V600E/K mutations.
Early impact of aortic wrapping on patients undergoing aortic valve replacement with mild to moderate ascending aorta dilatation
Authors: Ang Keng-Leong , Raheel Furqan , Bajaj Amrita , Sosnowski Andrzej , Galiñanes Manuel
Published: August 2010

Background

The management of mild to moderate dilatation of the ascending aorta of less than 5 cm is controversial, particularly when concomitant surgical correction of aortic valve is required. We investigate the impact of a simple method of aorta reduction using Dacron graft wrapping during aortic valve replacement on the rest of the aorta.

Methods

We studied 14 patients who had ascending aorta dilatation of 4-5 cm before undergoing aortic wrapping during their aortic valve replacement and compared with their post-operative imaging within a month.

Results

The diameters of the ascending aorta wrapped with the Dacron graft were significantly reduced within 4 weeks after surgery from 44.7 ± 2.6 to 33.6 ± 3.9 mm (p < 0.001). This was associated with significant reduction in the diameter of rest of ascending aorta: coronary sinuses (from 37.9 ± 4.9 mm to 33.3 ± 6.1 mm; p < 0.001), sinotubular junction (from 33.2 ± 4.7 mm to 30.6 ± 4.4 mm, p = 0.02), and aortic arch (from 34.7 ± 4.3 mm to 32.6 ± 4.1 mm, p = 0.03).

Conclusions

Reduction of ascending aortic dilatation by wrapping with a Dacron graft in this preliminary study is associated with favourable early reversed aortic remodelling. This supports the hypothesis that correction of mild-moderate dilatation of the ascending aorta with Dacron wrapping at the time of aortic valve surgery may prevent the progression of the dilatation, although the long-term study on a larger population is needed to confirm its benefits.
PKCα-induced drug resistance in pancreatic cancer cells is associated with transforming growth factor-β1
Authors: Chen Ying , Yu Guanzhen , Yu Danghui , Zhu Minghua
Published: August 2010

Background

Drug resistance remains a great challenge in the treatment of pancreatic cancer. The goal of this study was to determine whether TGF-β1 is associated with drug resistance in pancreatic cancer.

Methods

Pancreatic cancer BxPC3 cells were stably transfected with TGF-β1 cDNA. Cellular morphology and cell cycle were determined and the suppressive subtracted hybridization (SSH) assay was performed to identify differentially expressed genes induced by TGF-β1. Western blotting and immunohistochemistry were used to detect expression of TGF-β1-related genes in the cells and tissue samples. After that, the cells were further treated with an anti-cancer drug (e.g., cisplatin) after pre-incubated with the recombinant TGF-β1 plus PKCα inhibitor Gö6976. TGF-β1 type II receptor, TβRII was also knocked down using TβRII siRNA to assess the effects of these drugs in the cells. Cell viability was assessed by MTT assay.

Results

Overexpression of TGF-β1 leads to a markedly increased invasion potential but a reduced growth rate in BxPC3 cells. Recombinant TGF-β1 protein increases expression of PKCα in BxPC3 cells, a result that we confirmed by SSH. Moreover, TGF-β1 reduced the sensitivity of BxPC3 cells to cisplatin treatment, and this was mediated by upregulation of PKCα. However, blockage of PKCα with Gö6976 and TβRII with siRNA reversed the resistance of BxPC3 cells to gemcitabine, even in the presence of TGF-β1. Immunohistochemical data show that pancreatic cancers overexpress TGF-β1 and P-gp relative to normal tissues. In addition, TGF-β1 expression is associated with P-gp and membranous PKCα expression in pancreatic cancer.

Conclusions

TGF-β1-induced drug resistance in pancreatic cancer cells was associated with PKCα expression. The PKCα inhibitor Gö6976 could be a promising agent to sensitize pancreatic cancer cells to chemotherapy.
PPARγ modulated inflammatory response of human dendritic cell subsets to engulfed apoptotic neutrophils
Authors: Majai Gyöngyike , Gogolák Péter , Ambrus Csilla , Vereb György , Hodrea Judit , Fésüs László , Rajnavölgyi Éva
Published: August 2010

PPARγ expression and activation in CD1a– monocyte derived dendritic cells modulates the engulfment of and the cytokine and T cell response to apoptotic neutrophils.

The means of how phagocytes handle apoptotic cells has a great impact on the outcome of immune responses. Here, we show that phagocytosis of allogeneic, apoptotic neutrophils by human monocyte-derived DCs is slow and less efficient than that of macrophages, and CD1a– DCs are more active in the engulfment of apoptotic neutrophils than CD1a+ DCs. Blocking DC-SIGN function partially interferes with the uptake of apoptotic cells, and long-term interaction of apoptotic neutrophils with DCs makes them prone to proinflammatory cytokine responses. Engulfment of apoptotic cells sensitizes CD1a– DCs for high IL-8, TNF-α, IL-6, and CD1a+ cells for IL-12 and IL-10 cytokine secretion elicited by additional inflammatory stimuli, which also result in the polarization of autologous T lymphocytes to Th1 effector cells. Ligand-induced activation of PPARγ by RSG results in enhanced phagocytosis, but the proinflammatory response and the capacity to trigger Th1 cell activation of CD1a– DCs are not enhanced. These results demonstrate that DCs are able to respond to allogeneic, apoptotic neutrophils with inflammatory cytokines and T cell responses in a subtype-specific manner that is modulated by the anti-inflammatory effects of PPARγ.
The Receptor-Dependent Actions of 1,25-Dihydroxyvitamin D Are Required for Normal Growth Plate Maturation in NPt2a Knockout Mice
Authors: Miedlich Susanne U. , Zhu Eric D. , Sabbagh Yves , Demay Marie B.
Published: August 2010

Rickets is a growth plate abnormality observed in growing animals and humans. Rachitic expansion of the hypertrophic chondrocyte layer of the growth plate, in the setting of hypophosphatemia, is due to impaired apoptosis of these cells. Rickets is observed in humans and mice with X-linked hypophosphatemia that is associated with renal phosphate wasting secondary to elevated levels of fibroblast growth factor-23. Rickets is also seen in settings of impaired vitamin D action, due to elevated PTH levels that increase renal phosphate excretion. However, mice with hypophosphatemia secondary to ablation of the renal sodium-dependent phosphate transport protein 2a (Npt2a), have not been reported to develop rickets. Because activation of the mitochondrial apoptotic pathway by phosphate is required for hypertrophic chondrocyte apoptosis in vivo, investigations were undertaken to address this paradox. Analyses of the Npt2a null growth plate demonstrate expansion of the hypertrophic chondrocyte layer at 2 wk of age, with resolution of this abnormality by 5 wk of age. This is temporally associated with an increase in circulating levels of 1,25-dihydroxyvitamin D. To address whether the receptor-dependent actions of this steroid hormone are required for normalization of the growth plate phenotype, the Npt2a null mice were mated with mice lacking the vitamin D receptor or were rendered vitamin D deficient. These studies demonstrate that the receptor-dependent actions of 1,25-dihydroxyvitamin D are required for maintenance of a normal growth plate phenotype in the Npt2a null mice.
Improving Educational Opportunities: Can Public Administrators Build a Sustainable Middle Class in Zambia?
Authors: Lentz Corliss
Published: August 2010

Zambia has problems with its education system that inhibit the growth of an educated, middle-class workforce. While it has made dramatic progress in access to lower education in the past decade, it has had more difficulty expanding educational opportunities for grades 8–12 and in higher education. In addition to a persistently high HIV/AIDS infection rate, Zambia has a rapidly growing young population but lacks infrastructure, qualified teachers, and enough college graduates to achieve its educational goals. This article identifies the problems that threaten the educational system and makes recommendations to help Zambia achieve its goal to build a sustainable middle class.
Effect of Surface-oxidized Structure of Single-walled Carbon Nanotubes on Heterogeneous Direct Electron-transfer Reaction of Cytochrome c
Authors: Tominaga Masato , Yamaguchi Hiroyuki , Sakamoto Shingo , Taniguchi Isao
Published: August 2010

The redox reaction of cytochrome c was not observed at as-grown, high-quality, single-walled carbon nanotubes (SWCNTs) synthesized onto a gold electrode surface. On the other hand, at a gold electrode modified with SWCNTs with oxidized carbon species such as C–O, C=O, and O–C=O induced by UV–ozone treatment, a well-defined diffusion-controlled redox wave of cytochrome c was observed. The results clearly indicated that oxidized carbon species such as C–O, C=O, and O–C=O play an important role for the fast heterogeneous direct electron-transfer reaction of cytochrome c with CNTs.
Production and Analysis of Biodiesel from Non-Edible Seed Oil of Pistacia Chinensis
Authors: Qin Shenjun , Sun Yuzhuang , Meng Xiaocai , Zhang Shouxin
Published: August 2010

Pistacia Chinensis is a potential and suitable non-edible feedstock for biodiesel production in China. In the present paper, three extraction methods to obtain seed oil of Pistacia Chinensis were compared and the Soxhlet extraction was found as the most effective one. Two kinds of biodiesels were produced catalyzed homogeneously by sodium hydroxide from crude oil of Pistacia Chinensis in Hebei province and Jiangsu province. Fourier transform infrared spectroscopy was used to compare the alterations of the functional groups in the crude oils and their biodiesel products after transesterification, and gas chromatography-mass spectrometry and gas chromatography were used to compare the composition of the biodiesels qualitatively and quantitatively. The results show that the C18 fatty acid methyl esters are the main components in both the biodiesels, and the seed oil of Pistacia Chinensis from Hebei province is more suitable for biodiesel production than that from Jiangsu province in terms of their chemical structure.
Microwave Acid Digestion for the Determination of Metals in Subbitumnious Coal Bottom Ash by ICP-OES
Authors: Saydut Abdurrahman
Published: August 2010

The development of precise and easy determination method for the metals in fossil fuel is the essential factor for the study of problems which are caused by the existence of metals in fuel. Coal contains many kinds of mineral matter elements including metals derived from its generation. The sample preparation method developed for metal determination in coal by spectroanalytical technique is dry ashing, and wet acid microwave digestion. Microwave-acid digestion (MW-AD) followed by inductively coupled plasma-optical emission spectrometry (ICP-OES) was examined for the determination of metals (Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Zn) in coal bottom ash (CBA). Subbitumnious coal from Hazro deposits in SE Anatolia of Turkey has been used in this study. Metals in coal gave good recoveries for their certified or reference values.
Origin and Geological Significance of the Cross Fractures in the Upper Triassic Yanchang Formation, Ordos Basin, China
Authors: Zeng Lianbo , He Yonghong , Xiong Weiliang
Published: August 2010

Cross fractures are well developed in the Upper Triassic Yanchang Formation in the Ordos Basin. According to the data on outcrops and cores and to our mechanical experiments, the origin of these cross fractures is discussed and their influence on petroleum exploration and development is analyzed. Four assemblages of fractures were formed in the Upper Triassic Yanchang Formation within the Ordos Basin. But in a certain place, there are generally distributed two assemblages of cross fractures, i.e. E-W and S-N fractures, at the center of the basin, and NE-SW and SW-SE fractures in the southwest of the basin. Fractures here are mainly high-angle shear fractures that are nearly vertical to the beds that were formed during the Yanshan (135Ma) and Himalayan (65–23.3Ma) periods due to horizontal tectonic compression, deep burial and intense uplift or denudation. The rock anisotropy is the prime reason for impacts wrought on the development of different assemblages of cross fractures in some geological periods, which usually restricts the development of one assemblage of conjugate shear fracture. Theoretically, there should have been formed two assemblages of shear fractures in either tectonic period, and there should have developed four assemblages of shear fractures here. But, due to the effect of a strong rock anisotropy, in each period developed only one assemblage of fracture. Thus two assemblages of cross fractures are usually developed in each part of the Ordos Basin at present. The cross fractures are important pathway system for oil migration in the low-permeability sandstone reservoirs of the Upper Triassic Yanchang Formation. At the same time, they also serve as main channels for fluid flow during the water-injection development process and impact the development of such reservoirs.
Hierarchy Analysis for Flow Units Division of Low-Permeability Reservoir: A Case Study in Xifeng Oilfield, Ordos Basin
Authors: Lv Mingsheng , Chen Kaiyuan , Xue Liangqing , Su Yongdi , Li Ran
Published: August 2010

The Chang 8 Member of Yanchang Formation in Xifeng Oilfield is deposited by delta front, and the mircofacies contains distributary channel, mouth bar, sheet sands and interdistributary bay. The reservoirs within the Chang 8 Member are characterized by strong heterogeneity, great lateral change of facies and low permeability with a value of 0.1–10mD. It is significant for the effective development of these low-permeability reservoirs to divide the flow units accurately. Base on the principle that flow units are controlled by macroscopic sedimentation and microscopic petrophysics, a hierarchy analysis for flow units division was proposed. The reservoir unit can be subdivided into three hierarchies which comprises genetic unit, architectural unit and flow unit. Macroscopically, genetic unit is designated by sequence stratigraphic interpretation, and architectural unit is delineated within genetic unit by reservoir architecture analysis. Microscopically, flow unit is defined within architectural unit by petrophysical parameters measurement. The method was applied to divide flow units of low permeability reservoirs within the Chang 8 Member of Xifeng Oilfield. It was shown that the flow unit of type A and B with good development potential dominantly locate in the main part of distributary channel and mouth bar, and the flow unit of type C with poor development potential mainly locates in sheet sands, edges of mouth bar and distributary channel. The study indicates that the flow units are identified by the method which reflects macroscopic characteristics of sedimentation, as well as microscopic details of petrophysical properties.
A Simple Criterion for Low Frequency Noise Emission Assessment
Authors: Broner N.
Published: August 2010

There are many sources of Low Frequency Noise (LFN) in the environment and complaints about the effect of higher level LFN in the form in the form of “rumble”, a “feeling of pressure” and the resultant headaches and nausea have been known for decades. A number of different European methods have been suggested for assessment of LFN, all based on measured indoor noise levels. The administrative procedures used in individual countries to enforce any LFN criteria are quite different but they are all generally based on the assumption that the annoyance due to LFN is dependent on the relative SPL when compared to the threshold of audibility. In terms of simplicity of application, the determination of an overall noise level that could be used for assessment of LFN would be the optimum approach rather than requiring any detailed spectrum analysis and calculations. Ideally, LFN criteria should be set indoors where the LFN complaints normally occur. However, in planning terms, it is much easier to set criteria for the outside of residences. In this paper, we therefore propose criteria for the prevention of LFN complaints for both residential and commercial permisies based on the measured overall C-weighted SPL. We also consider the impact of LFN SPL fluctuations.
MesoDyn and Experimental Approach to the Structural Fabrication and Pore-Size Adjustment of SBA-15 Molecular Sieves
Authors: Huiyong Chen , Jianghong Wu , Shaojuan Luo , Hongxia Xi , Yu Qian
Published: August 2010

As the main structure-directing template, P123 performs a key role during the formation of the bimodal pore system of the micro–mesoporous silica SBA-15. In this paper, the method of mesoscopic dynamics (MesoDyn) has been applied to simulate the aggregation behaviour of the triblock copolymer P123 (PEO20PPO70PEO20), and to further explore the structure-formation mechanism and analyze the feasibility of accurately adjusting the pore size of SBA-15. In particular, the effect of the synthesis temperature on the P123 micelle size in the SBA-15 synthesis process has been investigated in detail due to its importance in adjusting the pore size of SBA-15. In addition, in order to validate the simulation results, a series of SBA-15 samples were synthesized at temperatures within the range 293–328 K.

The simulation results show that uniform spherical micelles of P123, composed of hydrophilic PEO coronas and hydrophobic PPO cores, can be formed in aqueous solutions. This provides a perfect explanation of the experimental findings of previous work. Moreover, it has also been found that the P123 micelle gradually expands as the temperature increases, which leads directly to an increase in the mesopore diameter of SBA-15. The relevant experimental results reported in this paper demonstrate this conclusion. Overall, the mesoscopic simulation method has been shown to be a valuable tool for exploring structure fabrication and for providing an accurate guide for adjusting the pore size of SBA-15, as well as being a strong complement and extension to the experimental approach.
Preparation and Characterization of Polyamidoxime Chelating Resin from Rubberwood Fibre-G-Polyacrylonitrile
Authors: Abuilaiwi Faraj A. , Atieh Muataz Ali , Ahmad Mansor B. , Ibrahim Nor Azowa , Rahman Mohamad Zaki Ab. , Yunus Wan Md. Zin Wan
Published: August 2010

Grafted rubberwood fibre was converted to polyamidoxime ion-exchange resin in order to remove heavy metal ions from aqueous solution. The cation-exchange resin existed predominantly in the syn-hydroxyamino form. The water uptake by the resin was ca. 31 g/g dry resin while its hydrogen ion capacity was 3.6 mmol/g. The adsorption capacity of the resin towards different metal ions from wastewater was determined at different pH values within the range 1–6. The prepared chelating ion-exchanger exhibited the highest adsorption capacity towards Cu2+ ions (3.83 mmol/g), followed by Cd2+, Fe3+, Pb2+, Ni2+ and Co3+ ions, respectively. The results showed that the adsorption capacity depended on the solution pH. Polyamidoxime ion-exchange resin was also used to separate Co3+ and Ni2+ ions from Cu2+ ions using a column technique. On passing Cu2+/Ni2+ and Cu2+/Co3+ ion mixtures through the resin at pH 3, Cu2+ ions were adsorbed by the resin but no sorption of Ni2+ or Co3+ ions was detected. Approximately 98% of the Cu2+ ions could be desorbed from the resin. FT-IR spectroscopy was used to confirm the conversion of polyacrylonitrile-g-rubberwood fibre to polyamidoxime.
Investigation of the Synthesis and Properties of Ternary V–Cu–Ce Oxides of Composition VxCuxCe1 – 2xO2
Authors: Attipa Christothea , Theocharis Charis R.
Published: August 2010

A co-precipitation method has been used to prepare ternary mixed oxides based on ceria with the general formula VxCuxCe1 – 2xO2, where x was varied between 0.05 and 0.45. The structural and surface properties as well as the morphologies of the solids were examined by thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction studies, nitrogen adsorption isotherms, Fourier-transform infrared spectroscopy and scanning electron microscopy.

For samples where the vanadium and copper content was low (x ≤ 0.3), the surface area increased and the pore distribution shifted towards the micropore range. The sample V0.05Cu0.05Ce0.9O2 exhibited the highest surface area and the sample V0.45Cu0.45Ce0.1O2 the smallest. The samples were calcined within the temperature range 473–1073 K. When the vanadium content was increased to x ≥ 0.3 and the calcination temperature set at 673 K, a phase with composition CeVO4 was detected via X-ray diffractometry, in addition to a V2O5 and a CeO2 phase. The FT-IR spectra confirmed the above results.
Adsorptivities of Extremely High Surface Area Activated Carbon Fibres for CH4 and H2
Authors: Rejifu A. , Noguchi H. , Ohba T. , Kanoh H. , Rodriguez-Reinoso F. , Kaneko K.
Published: August 2010

Activated carbon fibres with extremely high surface areas (ACFs) were prepared by CO2 re-activation using pitch-based ACFs having an original surface area of 1730 m2/g. The highest surface area of the re-activated ACFs was 2930 m2/g as determined from an αS-plot analysis of the nitrogen adsorption isotherm measured at 77 K. The ACF with the highest surface area showed excellent adsorptivity towards supercritical CH4 and H2. The amounts of CH4 and H2 adsorbed were enhanced by 52% and 30%, respectively, as a result of re-activation.
Computational Morphogenesis
Authors: Ohmori Hiroshi
Published: August 2010

Computational morphogenesis is the word generally used for expressing those techniques or ways of thought by which the configuration or the system of structures is generated mainly through the usage of computers, which is realized on the firm foundation of both FEM as a tool of numerical analysis and various methods based on relatively newly-developed algorithms for structural optimization. Recently, it has been gaining a considerable number of users such as structural engineers or architects for the structural design of actual buildings as well as proposals for architectural competitions. Here we present the state of the art in computational morphogenesis especially in Japan as well as the future prospects for computational morphogenesis.
Preliminary Design of a Floating Wind Turbine Support Structure and Relevant System Cost Assessment
Authors: Casale C. , Lembo E. , Serri L. , Viani S.
Published: August 2010

This paper describes the preliminary design of a floating support structure for offshore wind turbines that has been developed by ERSE (former CESI RICERCA). It considered the prospects that this kind of structure could hold for exploiting wind resources in the windiest sea areas along the coasts of Italy (Sardinia, Sicily, Apulia). A review of the various types of floating structure that have been devised worldwide for wind turbines has made it possible to single out the floating structure that looks most interesting from the technical and economic standpoint. Specifically, the selected structure is of the Tension Leg Platform (TLP) type. It consists of a nearly fully submerged hexagonal platform, which carries a 6 MW wind turbine and is linked to the sea bottom by 6 ties, which assure stability and limited tilting, even under the worst loads induced by wind and sea. The construction and installation phases for this structure have been analysed, and the most effective and economically viable techniques chosen. With a view for avoiding the use of expensive sea craft, the floating structure has been designed in such a way that it can be towed to its site with the wind turbine already standing on it.

A preliminary dimensioning of the floating structure has been carried out, along with technical verification of the main structural members. This work has been performed in cooperation with the engineering company TECON, which used, among others, the MOSES computation code by Ultramarine. Attention has also been devoted to the most suitable options for mooring the floating structure to the sea bottom.

To assess the behaviour of the floating system under the action of wind and waves, the computational code (BM) has been developed by ERSE. This code takes into account the whole “wind turbine + floating platform” system, represented by a scheme featuring 8 degrees of freedom. Using this code no anomalous or unexpected behaviours were observed. The costs of building and installing this floating system have been calculated, drawing on experience gained with similar offshore structures in the oil and gas fields. The unique conditions of Italy as regards shipyards, harbours, electrical grid layout etc. have been taken into account. Along with estimates of operation and maintenance costs, and annual energy yields, these results have allowed the calculation of the probable unit energy production costs of floating wind farms in deep-water coastal areas of Italy.
The Potential and Constraints of Wind Farm Development at Nearshore Sites in the Maltese Islands
Authors: Farrugia R.N. , Deidun A. , Debono G. , Mallia E.A. , Sant T.
Published: August 2010

The electrical energy requirements of the Maltese Islands are met in their entirety by two oil-fired electrical generation plants. In view of this complete dependence upon fossil fuels, investigations into the prospects of diversifying electrical generation by resorting to renewable energy technologies are particularly relevant. The archipelago has peculiar characteristics such as high population density, comparatively deep coastal waters and an economy based on tourism, manufacturing, marine-sector activities and services that make the integration of wind power generation projects challenging. Local government authorities commissioned the authors to assess the constraints related to wind farm development in a shallow water coastal area, known as is-Sikka l-Bajda, which could present a wind potential worth exploiting, and to recommend adequate mitigation measures to minimize any impacts and conflicts with stakeholders. These constraints include marine navigational aspects, fishing and aquaculture, tourism and other site-specific activities. Environmental constraints exist including the fact that the site is characterized by extensive seagrass ( Posidonia oceanica) meadows, that it is a priority habitat under the EU Habitats Directive, and that the site itself is a reef – another priority habitat within the same directive. The proposed near-shore site is also in the vicinity of a protected coastal bird rafting and bird nesting site for the Yelkouan Shearwater species. Submarine noise generation – particularly during the construction phase – is also of concern in view of the regular sighting of marine mammals in Maltese coastal waters. In the site evaluation exercise, another secondary site in the Maltese Islands, located off the north Gozo coast, was also assessed. Mitigation measures specific to the Sikka l-Bajda site proposed by the authors include the deployment of silt curtains, bubble screens and unobtrusive turbine lighting devices and avoiding utilisation of the reef area closest to the protected bird colony. Such measures also relate to the choice of the array design to minimise visual impact and to the period of the year when wind plant construction and deployment should take place to minimize impact on avifaunal populations. By declaring the marine area contiguous to the proposed nearshore wind facility development as off-limits to fishing vessels, a de facto ‘No-take’ Marine Protected Area can also be effectively instituted. One also expects submerged components of the nearshore wind facility to be colonized within a brief period by a diverse fouling community and that the same components act as Fish Aggregating Devices (FAD's), greatly enhancing fish populations in the area. In view of the current paucity in Mediterranean nearshore wind power facilities, the proposed project could potentially serve as a pilot project for the whole region, and also become a tourist attraction.
Intelligent Tools for Wind Resource Correlation
Authors: Butler David A
Published: August 2010

The use of linear correlation techniques to extend monitoring mast records is an important step in developing the energy estimates that underpin wind development business cases. Yet accuracy of the linear correlation technique rapidly degrades in complex conditions, and only allows correlation of a small number of parameters without introducing overwhelming model complexity.

This paper argues that artificial neural network (ANN) models offer an alternative that is simple to use, afford greater correlation options and provide improved data extension accuracy. This was explored through a practical data extension example, with the linear and ANN correlation performances directly compared.

The case study showed that the ANN correlation method provided superior accuracy compared to the linear correlation method, including a three fold improvement in Annual Energy Prediction (AEP) error.
Small Wind Turbines for Remote Power and Distributed Generation
Authors: Wood David
Published: August 2010

This paper provides an introduction to small horizontal axis wind turbines defined as having a power output less than about 50 kW. Some example turbines are shown along with typical operating parameters, partly to highlight some of the important differences between large and small turbines. Small turbines have traditionally been used for remote power production, but are increasingly finding application as components of distributed generation systems. The chief driver for this is the advent of feed-in tariffs in the western world in the form of premium prices for small-scale renewably generated electricity. Many of the technology issues common to both applications, including siting, optimum tower height, safety, and noise, are surveyed.
Selection of Nepalese Timber for Small Wind Turbine Blade Construction
Authors: Sinha Rakesh , Acharya Parash , Freere Peter , Sharma Ranjan , Ghimire Pramod , Mishnaevsky Leon
Published: August 2010

The paper describes the selection of Nepalese timber for development of small wind turbine blades on the basis of locally based low cost timbers, along with the selection of coatings to protect the timber from weathering. The selection criterion of timber includes timber mechanical properties, weathering effect on coatings, price, growth and availability of the timber. Mechanical properties such as Young's modulus of elasticity, breaking strength, breaking strain and Brinell's hardness of selected Nepalese timbers are presented. The effects of weathering on timbers without coating, and with different coatings, are analysed on the basis of the change in weight of the timber due to the effect of humidity and rainfall over a period of nineteen months. Degradation of different coatings of timber are compared.
On Blade Matching following Batch Production
Authors: Hitz K.L. , Wood D.H.
Published: August 2010

Wind turbine blades are usually made in batches and then matched in pairs or triples to form the rotor. This paper considers matching with the aim of avoiding or reducing the need for further adjustment of, say, the blade mass. Matching is considered optimal when it minimises the sum of the squared differences in the chosen matching parameter for all blade pairs or triples in a batch. It is proved that use of a simple parameter such as blade mass, or centre of mass, leads to optimal matching by ordering in terms of that parameter. More complex matching based on, say, minimising the eccentricity of the centre of mass, causes the parameter for one blade to depend on at least one other blade. Then ordering does not necessarily produce the optimal matching but, in all cases considered, it comes very close. A branch and bound algorithm is developed for complex matching and is shown to provide the optimal matching in a realistic time for batches of at least 20 blades.
Is Noise Exposure in Non-Industrial Work Environments Associated with Increased Sickness Absence?
Authors: Kristiansen Jesper
Published: August 2010

Noise in non-industrial workplaces is an increasing problem. Annoyance and complaints over noise are frequently reported in these workplaces, whereas the risk of hearing damage is usually not the major concern. An important question arises for this type of noise of low to moderate intensity; that is, if it could be a cause of increased sickness absence, for example, via a mechanism starting with job dissatisfaction or via health problems caused by the noise exposure. This paper discusses this question starting from epidemiological studies on sickness absence, and supplemented with field and laboratory studies that address intermediate steps on the path to sickness absence, such as job dissatisfaction, symptoms, and physiological stress reactions.

Only 3 epidemiological studies have investigated the effect of occupational noise on sickness absence. In the one study most pertinent to the question raised above, noise was associated with increased sickness absence in women holding jobs with complex work tasks.

No firm conclusions can be made based on the studies that have illuminated possible intermediate steps to sickness absence. One reason is the wide variety of scopes and contexts addressed in these studies; the workplace exposures that have been investigated spans noise in schools, open-plan offices, hospitals and noise from ventilation systems, etc. Another reason is the presence of major weaknesses in many of the studies, such as confounding effects and problematic exposure assessments. It is concluded that based on the level of the current evidence an association between occupational noise exposure of low to moderate level and sickness absence is possible, but to settle the question more high quality studies are needed.
On Checking the Rising Global Food Prices Due to Bio-Fuels Using Solar Energy
Authors: Sharan Anand M.
Published: August 2010

This paper deals with the pressing current global problem of the sudden price rise in food grains all over the world which is unprecedented. This has mainly arisen from use of food crops such as corn, sugar cane etc as bio-fuels.

This paper suggests use of solar energy which is not only widely abundant, it also does not cause global warming, a harmful effect due to the combustion of fuels whether bio-fuels or fossil. This paper also suggests use of other forms of vehicles which are far more economical to use.

In addition, this paper shows results of an efficient process of conversion of solar energy into useful forms; this process is the solar tracking process. If used world wide, one would obtain about 36% more energy whose cost is touching the sky these days.
Introductory Paper on Paradigm Shift Should We Change Emphasis in Greenhouse-Effect Research?
Authors: Rörsch Arthur
Published: August 2010

A paradigm is a set of scientific and metaphysical beliefs that provide a theoretical framework within which scientific theories can be tested. Replacement of an existing paradigm by another is called a paradigm shift. Most of the following papers in this issue argue that an alternative paradigm is needed for the functioning of the so-called greenhouse effect of the Earth and hence for the explanation of observed climatic change. Some others contest it. The observed coincidence between global warming and rise of CO2 in the atmosphere over the last century -more accurately measured over the last 30 years of it – need not indicate a causal relationship, and it certainly need not give rise to global catastrophe. An assumed correlation is based on the expectation that the infrared radiation from CO2 contributes significantly to the greenhouse effect of the Earth. However, irregularities in the trends raise doubts of such a simple causal relationship and, at least, considerable doubt about the magnitude of such an expected effect.
Tropical Rainstorm Feedback
Authors: van Andel Noor
Published: August 2010

In the set of radiative feedbacks to global warming due to a doubling of the CO2 concentration, from all the models the increase in latent heat transfer as a consequence of an increase of [sea] surface temperature is left out. Starting from measurements of increased evaporation and increase of wind speed as a function of sea surface temperature increase, I derive a large global feedback of −20 Wm−2 K−1. This negative feedback is much larger than the balance of feedbacks, range +0.8 to +2 Wm−2 K−1, included in the climate models. If the latent heat transfer feedback, i.e. tropical rainstorms, would be included in the models, the local climate sensitivity would decrease from 1.5 to 4 °C for a doubling of CO2 to less than 0.2 °C. This is lower than the temperature variations due to solar magnetic, ocean current and volcanic aerosol effects
Flanking Transmission Measurements: Part 1- Measurement Techniques
Authors: Emms Grant , Walther Tony
Published: August 2010

Recently a series of building acoustics measurements were performed at the BRANZ site in Judgeford, New Zealand. A special four-room test facility was built to enable a lightweight horizontal-cruciform building section to be tested. Shielding methods were used to measure the sound transmission through the various possible paths, direct and flanking for both airborne and impact sound. The results were also recombined to estimate the results for flanking configurations other than those tested. This paper presents the test facility, discusses the measurement techniques and presents some results which illustrated the measurement technique. A subsequent paper (part 2) will summarise the complete results of the test series.
Evaluated Uncertainties for Measurements of Airborne Sound Attenuation between Rooms in Buildings
Authors: Seddeq Hoda S.
Published: August 2010

The standard ISO/IEC 17025:2005 “General requirements for the competence of testing and calibration laboratories” introduces the necessity of evaluation of measurement uncertainties for making them reliable and comparable. In order to fulfill acoustic comfort conditions indoors, building acoustic have to establishes a set of criteria for the acoustic performance of the building. These criteria may be expressed in terms of permissible minimum values for normalized noise reduction NNR, noise reduction NR or apparent transmission loss ATL. This paper discusses the uncertainty sources and presents a methodology for the calculation of uncertainty of the airborne sound insulation between rooms carried out according to the of standards ASTME 336 and examples of uncertainty budget, evaluated for the measurement results of the sound insulation. The range of values obtained for the measurement results uncertainty is 0.68 to 1.77.
Deconvolved Stochastic Seismic Excitation Effect on the Nonlinear Response of Asphaltic Lining Dam-Foundation Interaction Systems
Authors: Hacıefendioğlu Kemal
Published: August 2010

The effect of the deconvolved stochastic seismic excitation on the nonlinear response of dam-foundation interaction systems is investigated in this paper using the equivalent linear method. For this purpose, three different earthquake input mechanisms are used: the standard-rigid-base input model, the massless-foundation input model and the deconvolved-base-rock input model. The spatial variability of ground motion including the incoherence and wave-passage effects are taken into account in the analyses. The Izmit earthquake in 1999 is selected as sample ground motion. Two-dimensional interface finite elements are used between the dam-soil deposit and the asphalt face and also between the foundation-soil deposit and the cut-off wall. The mean of the absolute maximum displacement and stress values obtained from the three earthquake input models are compared with each other.
Field Investigation on Dynamics of Railway Track Pre-Stressed Concrete Sleepers
Authors: Sadeghi J.
Published: August 2010

A comprehensive field investigation was made with the aim of achieving a better understanding of the dynamics of railway track pre-stressed concrete sleepers. Modal analysis and free decay method were used to determine the natural frequencies, model shapes and damping of sleepers. The validity of the results is discussed by comparing the results obtained here with those available in the literature. In order to investigate the characteristics of the dynamics of the loads imposed on the sleepers, load cells were installed between the rail seat and the sleeper and beneath the sleeper, recording the interaction between both sleeper and rail, and sleeper and ballast. The loads transferred from the rail to the sleeper and from the sleeper to the ballast were measured as a function of train speed. The rail seat load and the contact pressure between the ballast and the sleepers versus train axle loads and train speeds were recorded. The effects of the sleeper supporting conditions on the sleeper dynamic behaviour were investigated. The ratios of the rail seat load and the ballast contact pressure to the wheel load were obtained from the analyses of the field test results. These ratios were used to calculate the dynamic impact factors and ballast-sleeper pressure distribution patterns required for the design of sleepers. The methods, the test procedures and the results are presented and discussed in this paper.
Review of Condition Assessment and Retrofitting Techniques for Timber Bridge Assets in Australia
Authors: Balendra T. , Wilson J.L. , Gad E.F.
Published: August 2010

This paper provides an overview of the types of timber bridges in Australia and identifies the shortcoming associated with the ageing stock in order to preserve these assets and render them safe and useable under new loading standards. Methods available to assess the condition and residual capacity of timber bridges by non destructive techniques and retrofitting techniques to enhance the strength are discussed, with the objective of increasing the design life and satisfying strength criterion.
The Group Search Optimizer and its Application to Truss Structure Design
Authors: Li Li-Juan , Xu Xiao-Tong , Liu Feng , Wu Q.H.
Published: August 2010

This paper introduces a novel optimization algorithm, group search optimizer (GSO) algorithm. The implementation method of this algorithm is presented in detail. The GSO is used to investigate the truss structures with continuous variables and was tested by three truss structure optimization problems. The optimization results were compared with those of the particle swarm optimizer (PSO), the particle swarm optimizer with passive congregation (PSOPC) and the heuristic particle swarm optimizer (HPSO). The calculation results show that the GSO has preferable convergence rate and accuracy. Results from the three tested cases illustrate the competitive ability of the GSO to find the optimal results. It is desired for GSO to be used for structural optimal design problems.
Performance and Design Issues for High Strength Steel in Structures
Authors: Bjorhovde Reidar
Published: August 2010

Steel has been used in a very large number of structures for almost 150 years, and the material has undergone major changes over that period. For many years the primary grades were carbon-manganese steel with low strength and high deformability. However, structural systems have evolved greatly, with taller buildings and longer span structures of all kinds. Along with new directions in architectural expression, engineering modeling and design techniques have been affected by computational equipment, and fabrication and erection changes have followed suit. As these advances have taken place, significant demands for higher performing materials have evolved, to the extent that ultra high strength steels with yield stress levels of 700 MPa and much higher are now being considered. The paper examines these developments, including very recent findings from a variety of sources, and looks to the practical uses of the high strengths. The discussion focuses on performance needs, steel products, fabrication options and realistic economies of scale. It is clear that high strength by itself is not a solution, and numerous options need to be evaluated before selecting systems and materials.
Use of Alternative Steel in Building Steelwork Design to BS 5950
Authors: Chiew S.P. , Beh C.T.
Published: August 2010

In April 2008, the Building and Construction Authority of Singapore releases design guide BC 1: 2008 to the industry and alternative steel materials which are manufactured to non-BS standards are now permitted in building structural steelworks designed to BS 5950. This paper examines the BC 1 requirements for material performance and quality assurance vis-à-vis the use of such alternative steel materials in design. A list of certified alternative steel materials complying with the minimal essential material performance requirements is compiled. These certified materials are treated as per normal without any restriction or downgrading in design if they are produced by steel mills who can meet the quality assurance requirements. Emphasis is now placed on our stockholders and traders to source and import into Singapore steel materials from audited mills that have in place stringent factory production control system and proper mill test certification. All key stakeholders – manufacturers, stockholders, traders, auditors, fabricators and engineers have a duty and are expected to play a role in maintaining quality in material usage in Singapore's steel construction industry.