bluuebunny/crossref_metadata_2025 huggingface dataset:
Grazers: biocatalysts of terrestrial silica cycling
Authors: Vandevenne Floor Ina , Barão Ana Lúcia , Schoelynck Jonas , Smis Adriaan , Ryken Nick , Van Damme Stefan , Meire Patrick , Struyf Eric
Published: October 2013

Silica is well known for its role as inducible defence mechanism countering herbivore attack, mainly through precipitation of opaline, biogenic silica (BSi) bodies (phytoliths) in plant epidermal tissues. Even though grazing strongly interacts with other element cycles, its impact on terrestrial silica cycling has never been thoroughly considered. Here, BSi content of ingested grass, hay and faeces of large herbivores was quantified by performing multiple chemical extraction procedures for BSi, allowing the assessment of chemical reactivity. Dissolution experiments with grass and faeces were carried out to measure direct availability of BSi for dissolution. Average BSi and readily soluble silica numbers were higher in faeces as compared with grass or hay, and differences between herbivores could be related to distinct digestive strategies. Reactivity and dissolvability of BSi increases after digestion, mainly due to degradation of organic matrices, resulting in higher silica turnover rates and mobilization potential from terrestrial to aquatic ecosystems in non-grazed versus grazed pasture systems (2 versus 20 kg Si ha
−1
y
−1
). Our results suggest a crucial yet currently unexplored role of herbivores in determining silica export from land to ocean, where its availability is linked to eutrophication events and carbon sequestration through C–Si diatom interactions.
Diurnal fluctuations in seawater pH influence the response of a calcifying macroalga to ocean acidification
Authors: Cornwall Christopher E. , Hepburn Christopher D. , McGraw Christina M. , Currie Kim I. , Pilditch Conrad A. , Hunter Keith A. , Boyd Philip W. , Hurd Catriona L.
Published: October 2013

Coastal ecosystems that are characterized by kelp forests encounter daily pH fluctuations, driven by photosynthesis and respiration, which are larger than pH changes owing to ocean acidification (OA) projected for surface ocean waters by 2100. We investigated whether mimicry of biologically mediated diurnal shifts in pH—based for the first time on pH time-series measurements within a kelp forest—would offset or amplify the negative effects of OA on calcifiers. In a 40-day laboratory experiment, the calcifying coralline macroalga,Arthrocardia corymbosa, was exposed to two mean pH treatments (8.05 or 7.65). For each mean, two experimental pH manipulations were applied. In one treatment, pH was held constant. In the second treatment, pH was manipulated around the mean (as a step-function), 0.4 pH units higher during daylight and 0.4 units lower during darkness to approximate diurnal fluctuations in a kelp forest. In all cases, growth rates were lower at a reduced mean pH, and fluctuations in pH acted additively to further reduce growth. Photosynthesis, recruitment and elemental composition did not change with pH, but δ13C increased at lower mean pH. Including environmental heterogeneity in experimental design will assist with a more accurate assessment of the responses of calcifiers to OA.
Diaphorobacter aerolatus sp. nov., isolated from air, and emended description of the genus Diaphorobacter
Authors: Kim Soo-Jin , Moon Ji-Young , Ahn Jae-Hyung , Weon Hang-Yeon , Hong Seung-Beom , Seok Soon-Ja , Kwon Soon-Wo
Published: October 2013

A Gram-stain-negative, non-motile, aerobic rod, designated 8604S-37T, was isolated from an outdoor air sample collected in Suwon region, Republic of Korea. The isolate was catalase-positive and oxidase-negative. 16S rRNA gene sequence analysis indicated that strain 8604S-37T was most closely related to

Diaphorobacter nitroreducens

NA10BT and

Diaphorobacter oryzae

RF3T, with which it shared 97.0 % 16S rRNA gene sequence similarity. Strain 8604S-37T grew at 10–37 °C (optimum 28 °C; no growth occurred at 4 or 40 °C) and pH 5–9 (optimum pH 7). The strain tolerated up to 3 % NaCl (w/v) (optimum 0 %). The only respiratory quinone was ubiquinone-8 (Q-8). The polar lipid profile comprised phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and one unknown aminolipid. The major fatty acids were C16 : 0, summed feature 3 (comprising C16 : 1ω7c and/or iso-C15 : 0 2-OH), summed feature 8 (C18 : 1ω6c and/or C18 : 1ω7c) and C17 : 0 cyclo, and the predominant hydroxy fatty acid was C10 : 0 3-OH. Strain 8604S-37T exhibited less than 50 % DNA–DNA relatedness with

Diaphorobacter nitroreducens

KACC 13856T and

Diaphorobacter oryzae

KACC 16857T. The DNA G+C content was 65 mol%. Strain 8604S-37T represents a novel species of the genus

Diaphorobacter

, for which the name Diaphorobacter aerolatus sp. nov. is proposed. The type strain is 8604S-37T ( = KACC 16536T = NBRC 108926T). An emended description of the genus

Diaphorobacter

is also proposed.
Marinomonas fungiae sp. nov., isolated from the coral Fungia echinata from the Andaman Sea
Authors: Kumari Prabla , Poddar Abhijit , Das Subrata K.
Published: October 2013

A novel aerobic marine bacterium, strain AN44T, was isolated from the coral Fungia echinata sampled from the Andaman Sea, India. Cells were Gram-negative, motile and rod-shaped. Oxidase and catalase tests were positive. Heterotrophic growth was observed at pH 5.5–10 and at 16–42 °C, with optimum growth at pH 7–8 and 28 °C. Strain AN44T grew in the presence of 0.5–11 % (w/v) NaCl; the optimal NaCl concentration for growth was 3–5 %. The DNA G+C content was 47.8 mol%. Predominant cellular fatty acids of strain AN44T were C18 : 1ω7c, C16 : 1ω7c/C16 : 1ω6c, C16 : 0, C10 : 0 3-OH, C12 : 0, C10 : 0, C14 : 0 and C18 : 0. The sole isoprenoid ubiquinone was Q-8. The polar lipids were an unidentified phospholipid, an unidentified aminophospholipid and two unidentified glycolipids. 16S rRNA gene sequence comparisons revealed that strain AN44T clustered within the radiation of the genus

Marinomonas

and showed similarity of 97.9 % with

Marinomonas ostreistagni

UST010306-043T, 97.8 % with

Marinomonas aquimarina

11SM4T, 97.1 % with

Marinomonas brasilensis

R-40503T and 97.0 % with

Marinomonas communis

8T. However, DNA–DNA relatedness between strain AN44T and closely related type strains was well below 70 %. On the basis of the data from the present polyphasic taxonomic study, strain AN44T is considered to represent a novel species of the genus

Marinomonas

, for which the name

Marinomonas

fungiae sp. nov. is proposed. The type strain is AN44T ( = JCM 18476T = LMG 27065T).
Pathological findings and diagnostic implications of a rhesus macaque (Macaca mulatta) model of aerosol-exposure melioidosis (Burkholderia pseudomallei)
Authors: Yingst Samuel L. , Facemire Paul , Chuvala Lara , Norwood David , Wolcott Mark , Alves Derron A.
Published: October 2013

Aerosolized Burkholderia pseudomallei, the causative agent of melioidosis, can infect many species of mammals (including humans), causing rapid, severe pneumonia with high mortality. Diagnosis in humans is challenging, as few organisms can be detected in blood or other non-invasive samples. Although it cannot be said that the model is established, studies to date indicate that rhesus macaques may represent a good model of human melioidosis. This is supported by the results of this study. The early progression of meliodosis in the rhesus macaque was studied in an effort to better understand the disease and the application of rapid diagnostic methods. Results indicate that a PCR analysis of key diagnostic samples such as nasal swabs, throat swabs, tracheo bronchial lymph node aspirates and broncho-alveolar lavage may be a useful component of a rapid diagnostic algorithm in case of aerosol exposure.
In Vivo Intracellular pH Measurements in Tobacco andArabidopsisReveal an Unexpected pH Gradient in the Endomembrane System
Authors: Martinière Alexandre , Bassil Elias , Jublanc Elodie , Alcon Carine , Reguera Maria , Sentenac Hervé , Blumwald Eduardo , Paris Nadine
Published: October 2013

The pH homeostasis of endomembranes is essential for cellular functions. In order to provide direct pH measurements in the endomembrane system lumen, we targeted genetically encoded ratiometric pH sensors to the cytosol, the endoplasmic reticulum, and the trans-Golgi, or the compartments labeled by the vacuolar sorting receptor (VSR), which includes the trans-Golgi network and prevacuoles. Using noninvasive live-cell imaging to measure pH, we show that a gradual acidification from the endoplasmic reticulum to the lytic vacuole exists, in both tobacco (Nicotiana tabacum) epidermal (ΔpH −1.5) and Arabidopsis thaliana root cells (ΔpH −2.1). The average pH in VSR compartments was intermediate between that of the trans-Golgi and the vacuole. Combining pH measurements with in vivo colocalization experiments, we found that the trans-Golgi network had an acidic pH of 6.1, while the prevacuole and late prevacuole were both more alkaline, with pH of 6.6 and 7.1, respectively. We also showed that endosomal pH, and subsequently vacuolar trafficking of soluble proteins, requires both vacuolar-type H+ ATPase–dependent acidification as well as proton efflux mediated at least by the activity of endosomal sodium/proton NHX-type antiporters.
ArabidopsisRECEPTOR-LIKE PROTEIN30 and Receptor-Like Kinase SUPPRESSOR OF BIR1-1/EVERSHED Mediate Innate Immunity to Necrotrophic Fungi
Authors: Zhang Weiguo , Fraiture Malou , Kolb Dagmar , Löffelhardt Birgit , Desaki Yoshitake , Boutrot Freddy F.G. , Tör Mahmut , Zipfel Cyril , Gust Andrea A. , Brunner Frédéric
Published: October 2013

Effective plant defense strategies rely in part on the perception of non-self determinants, so-called microbe-associated molecular patterns (MAMPs), by transmembrane pattern recognition receptors leading to MAMP-triggered immunity. Plant resistance against necrotrophic pathogens with a broad host range is complex and yet not well understood. Particularly, it is unclear if resistance to necrotrophs involves pattern recognition receptors. Here, we partially purified a novel proteinaceous elicitor called SCLEROTINIA CULTURE FILTRATE ELICITOR1 (SCFE1) from the necrotrophic fungal pathogen Sclerotinia sclerotiorum that induces typical MAMP-triggered immune responses in Arabidopsis thaliana. Analysis of natural genetic variation revealed five Arabidopsis accessions (Mt-0, Lov-1, Lov-5, Br-0, and Sq-1) that are fully insensitive to the SCFE1-containing fraction. We used a forward genetics approach and mapped the locus determining SCFE1 sensitivity to RECEPTOR-LIKE PROTEIN30 (RLP30). We also show that SCFE1-triggered immune responses engage a signaling pathway dependent on the regulatory receptor-like kinases BRASSINOSTEROID INSENSITIVE1-ASSOCIATED RECEPTOR KINASE1 (BAK1) and SUPPRESSOR OF BIR1-1/EVERSHED (SOBIR1/EVR). Mutants of RLP30, BAK1, and SOBIR1 are more susceptible to S. sclerotiorum and the related fungus Botrytis cinerea. The presence of an elicitor in S. sclerotiorum evoking MAMP-triggered immune responses and sensed by RLP30/SOBIR1/BAK1 demonstrates the relevance of MAMP-triggered immunity in resistance to necrotrophic fungi.
Banking against Humanity: The Holocaust, the Reichsbank Loot Film and the American Prosecution at the Nuremberg International Military Tribunal
Authors: Reynolds Kevin
Published: October 2013

This article examines the complex circumstances surrounding the use of Reichsbank Loot, a film shown by the American Prosecution at the Trial of the Major War Criminals before the International Military Tribunal at Nuremberg. Used as part of the case against former Reichsbank President and Minister of Economics, Walther Funk, who was charged, inter alia, with crimes against humanity, the film appeared to provide straightforward visual evidence of some of the products of genocide that had been handled by the Reichsbank during the war. It consisted of a simple sequence of close‐up views of valuables such as necklaces, rings, gems, broaches and fob watches. It also showed boxes full of gold dentures. Yet, ulike other films shown at Nuremberg, the veracity of this American‐made film was called into question by a number of people, both at the trial and since, most notably by the convicted Holocaust denier David Irving. Now that it has recently become publicly available, the time is ripe for a reassessment of the film and the case against Funk that it supported. This article assesses the veracity of the film and offers some explanations why the silence relating to the film and the case more generally has persisted until now.
Imperialism, Anti‐Imperialism and the Problem of Genocide, Past and Present
Authors: Spencer Philip
Published: October 2013

In recent years, there have been signs of a significant ‘anti‐imperialist’ turn in genocide studies. Challenging what has been described as a hitherto predominantly liberal approach, a number of genocide scholars have adopted a more critical attitude towards the history of imperialism, and projected a broader arc of explanation, linking genocides committed by western states in the construction of their empires to genocides committed in the twentieth and twenty‐first centuries. There is too much insight, undoubtedly, in an anti‐imperialist approach to contemplate discarding it. It helps us understand why genocides undoubtedly committed by western imperialist states took place in the past. It provides important elements of a vital critique of the international order, fashioned by western imperialist states, within which some postcolonial states have been able to commit genocide. It helps us understand why some western states colluded with or facilitated genocide, as inIndonesia in the 1960s orGuatemala in the 1980s, or blocked intervention to halt or prevent it, as inBangladesh in the 1970s andRwanda in the 1990s. But it cannot do everything, and some of the difficulties identified here will arise when it is taken too far, when there is an attempt to fit everything within a framework of analysis that cannot bear the weight put upon it. Imperialism has been at times and in places central to the occurrence of genocide, but not everywhere, not at all times, and to a very large extent not since the Convention.
Evaluation of a PCR method to determine the clinical significance of blood cultures with Staphylococcus epidermidis in patients with hematological malignancies
Authors: Ahlstrand Erik , Bäckman Anders , Persson Lennart , Mölling Paula , Tidefelt Ulf , Söderquist Bo
Published: October 2013

The aim was to investigate whether the detection and quantification of Staphylococcus epidermidis DNA in blood could distinguish S. epidermidis blood stream infections (BSIs) from blood culture contaminations in patients with hematological malignancies. The hld gene was chosen to identify S. epidermidis DNA and DNA in blood samples was detected by real‐time PCR. Blood samples were obtained simultaneously with blood cultures positive for S. epidermidis (n = 30), during blood culture‐negative episodes (n = 10) and episodes of bacteremia with other bacteria than S. epidermidis (n = 4) and from healthy blood donors (n = 10). In addition, DNA from S. epidermidis and a selection of other bacterial species were analyzed. Three different sets of criteria were used to classify episodes with positive blood cultures with S. epidermidis as BSIs or contaminations. All DNA preparations from S. epidermidis (n = 48) were hld‐positive, but other bacterial species (n = 13) were negative. Sixteen (53%) of 30 blood samples from patients with blood cultures positive for S. epidermidis were hld‐positive, but none of the controls. There was no clear association between a positive hld PCR and episodes interpreted as BSIs. In conclusion, hld PCR failed to distinguish S. epidermidis BSIs from blood culture contaminations in patients with hematological malignancies.
Pregnancy complications and obstetric care in women with inherited bleeding disorders
Authors: Kadir R. A. , Davies J. , Winikoff R. , Pollard D. , Peyvandi F. , Garagiola I. , Pabinger I. , Federici A. B.
Published: October 2013

Women with inherited bleeding disorders (IBD) require the input of a multidisciplinary team to improve outcomes of pregnancy. The role of the haemophilia nurse within the multidisciplinary team is to provide educational and emotional support to the women and to facilitate and co‐ordinate patient‐centred care. Prenatal diagnosis in cases of haemophilia is an integral part of the management of early pregnancy with a recent drive towards non‐invasive prenatal diagnostic techniques. There is a current lack of data on the risk of miscarriage and bleeding complications during pregnancy. A clear association has only been established in women with fibrinogen and factor XIII deficiency. In the affected neonate with severe bleeding disorders such as haemophilia, the risk of head bleeding is significant, and appropriate management of labour and delivery has an important impact on reducing the risk. Women withIBDare at risk of both primary and secondary postpartum haemorrhage. Appropriate risk assessment and advance planning for haemostatic cover can reduce the bleeding risk.
Molecular systematics of four endemic Batrachospermaceae (Rhodophyta) species in China with multilocus data
Authors: JI Li , XIE Shu‐Lian , FENG Jia , CHEN Le , WANG Jie
Published: October 2013

Four endemic Batrachospermaceae species in China, Batrachospermum hongdongense Xie & Feng, Batrachospermum longipedicellatum Hua & Shi, Kumanoa curvata (Shi) Vis et al., and Kumanoa intorta (Jao) Entwisle et al., were analyzed with multilocus data in order to assess their phylogenetic placement. Multilocus molecular data from one nuclear gene (the ribosomal SSU), one chloroplast gene (rbcL), and two mitochondrial genes (COI and the cox2‐3 spacer) as well as morphological studies were used to determine the phylogenetic relationships of these endemic species within the Batrachospermales. Batrachospermum hongdongense and B. longipedicellatum had previously been placed in Batrachospermum section Batrachospermum, but based on the data from this study they should be transferred into section Helminthoidea. Kumanoa curvata and K. intorta clearly belong to the newly established genus Kumanoa.
On a classification of irreducible admissible modulo representations of a -adic split reductive group
Authors: Abe Noriyuki
Published: October 2013

We give a classification of irreducible admissible modulo $p$ representations of a split$p$-adic reductive group in terms of supersingular representations. This is a generalization of a theorem of Herzig.
Test Rig for Spline Couplings Working in Misaligned Conditions
Authors: Cuffaro Vincenzo , Curà Francesca , Mura Andrea
Published: October 2013

This paper presents a novel spline couplings test rig. Its peculiarity is to allow angular misalignments between hub and shaft in order to investigate the behavior of spline couplings in real working conditions, in particular, to investigate fretting wear phenomena. A preliminary experimental activity has been carried out showing a correct behavior of the test rig from all points of view. A preliminary approximated estimation of the test articles fretting wear has been obtained by means of two experimental parameters: Ra roughness and the amount of angular rotation clearance. An estimation of the Ruiz parameter has also been obtained.
Stress, Strain, and Energy at Fracture of Degraded Surfaces: Study of Replicates of Rough Surfaces
Authors: Medina Hector E. , Hinderliter Brian
Published: October 2013

Due to the aging of structures, the issues of plant life management and license extension are receiving increasing emphasis in many countries. Understanding failure of structures due to random roughness on surfaces at early stages of degradation is therefore crucial. It has been shown that even slightly sinusoidal roughness can increase stress concentration by a factor of two or three, which can be critical for a brittle component due to the significant reduction of its load-carrying capacity, even with slight roughness. A more in-depth fracture analysis of surfaces possessing random roughness is needed in order to more profoundly understand, and, hence, develop models that will predict more accurately, failure of structural materials exposed to degrading, in-service conditions. Using a technique previously developed and successfully applied, replicates of random rough surfaces, imprinted with various levels of degradation, and at three distinct auto correlation lengths, were realized and mechanical testing was performed on them. The stress, strain, and energy at fracture are reported. Finite element analysis was carried out to elucidate experimental results. Besides the expected reduction of energy at fracture with degradation, a relaxation region was observed where the energy slightly increases. This phenomenon implies that even after degradation has progressed there is a local maximum of energy at fracture due to the competing effect of tendons and growth of pits. The results find applications on the early stage of maintenance of surfaces of structures in service.
Bolted Joints Modeling Techniques, Analytical, Stochastic and FEA Comparison
Authors: Amir Yosef , Govindarajan S. , Iyyanar Saravanakumar
Published: October 2013

Bolted joints Design analyses are in general, very complex and it is very difficult to find a single technique to study the complete behavior of the bolted joints. The most popular analytical method is the well-known VDI 2230 which addresses most of the cases very well. This analytical method uses extreme values for critical parameter variations and is considered to be conservative, but the quickest method. Stochastic analysis is a more advanced method where variations in critical parameters are modeled as statistical distributions and Monte Carlo simulations allow predicting the behaviors of bolted joints through selective parameter variations. Finite element analysis of bolted joints is another methodology to analyze complex bolted joint designs. Though advances in FE modeling techniques help to model bolted joints more accurately, different failure modes require different modeling techniques. For practical complex bolted joints design analysis, a hybrid of analytical and different FEA models is needed for a full analysis; but a combination of FEA techniques can be used to study any bolted joint in detail for all the failure modes. Hence, it is important to study and understand the limitations of each of the modeling techniques. This paper looks at analytical and stochastic methods of bolted joints as well as three different FEA methods — 3D, Axisymmetric and Beam & Rigid Spider — to study different failure modes. Parametric (DOE) FEA simulation technique for variation parameters bolted joint behavior prediction was investigated; this paper examined the DOE parameter of coefficient of friction. A general case study is used as benchmark for comparison between the techniques and to quantify the advantages and disadvantages of each method.
Flow Field and Vibration Behavior of the Rotor due to Mistuning IGV in a Transonic Compressor
Authors: Yang Xiaodong , Hou Anping , Zhang Mingming , Li Manlu , Wang Zhuoqi
Published: October 2013

A fluid-structure coupled approach is utilized to study the influence of mistuning IGV blade on rotor flow field and blade vibration behavior of a transonic compressor. Interaction between fluid and structure are dealt with in a coupled manner, based on the interface exchange of information between the aerodynamic and structural model. The computation fluid mesh is updated at every time step with an improved algebraic method. The unsteady flow field of IGV/rotor with one mistuned IGV blade is studied using full-annulus, 3D CFD model. Then a reduced half-annulus CFD model with one mistuned IGV blade coupled with rotor FEA model is used to identify model shapes, frequencies, vibration stress and the structural deformations. The results show that the mistuning IGV cause the performance map of rotor shift towards the lower flow rate from the rotor with normal IGV. A significant low-frequency and its multiple pressure fluctuation appear in mistuning IGV wake, the fundamental frequency of IGV wake is closely related with the number of mistuning blade. Compared with normal IGV model, the vibration characteristics of rotor blade changed, blade vibration frequency is the same as the main frequency of mistuning IGV wake.
Tip Flowfield of a Low Aspect Ratio Circulation Control Wing With Spanwise Variation in Efflux
Authors: Perry Matthew , Miklosovic David
Published: October 2013

A stereoscopic particle image velocimetry (SPIV) system was used in a low-speed wind tunnel to measure the external flowfield of a circulation control (CC) wing having an aspect ratio of 1.1. This ongoing project, sponsored by the Office of Naval Research, sought to further the knowledge of the jet interactions and the wingtip vortex formation through 3-component, planar velocity surveys. The CC wing tested had a 20% elliptic airfoil section with a trailing edge Coanda surface that was intended to increase circulation control effectiveness through a segmented system that could create spanwise massflow efflux profiles.

To date, 1.2 TB of raw SPIV data have been acquired in one of two wake station planes at z/c = 1.25 over the vertical region of 0.13 < y/b < 0.87 (i.e, the tip region). The three-component velocity data revealed the nature of the interaction of the jet with the external flowfield and the temporal variability at an overall momentum coefficient of 0.08 with spanwise variations in the trailing edge efflux. The results from these tests will be used to quantify, for the first time, the effects of spanwise massflow distributions on the 3D velocity field near the trailing edge, the stall modes, jet interactions, and the overall performance of a CC wing of this geometry.
A Quantitative Evaluation of the Quality of Recycled Steel in Uganda
Authors: Senfuka C. , Kirabira J. B. , Byaruhanga J. K.
Published: October 2013

All steel made in Uganda is currently manufactured from scrap. Such steel has often been characterized by unpredictable performance in consonance with its inconsistent raw material inputs. This study evaluates and relates the mechanical, metallurgical and geometrical properties of these bars in order to identify the factors underlying the performance of the products from this steel and examine the relationship with their scrap content. In order to study the steels, tensile, torsion and micrographic tests have been carried out together with spark emission spectrometry on samples collected from different plants. The test results generally indicate impressive steel resilience, strength and metallographic properties in spite of relatively high and irregular carbon content. Limited weldability, uniaxiality of properties, uneven scatter of microelements and substantial non-uniformity of longitudinal mechanical properties have been observed. Rolling and post rolling defects have been noted. The geometric reliability of the bars has also been found generally low. Improvement of secondary refinement, use of direct reduced iron (DRI) diluent and more diligent sorting have suggested as solutions.
Robust Mechatronic Actuation System for UAV Primary Flight Controls
Authors: Ferrara Davide , Jacazio Giovanni , Mornacchi Andrea , Sorli Massimo
Published: October 2013

The paper describes the initial results of a research activity aimed at developing a high integrity mechatronic system for UAVs primary flight controls able to ensure the necessary flight safety and to enhance the system availability by implementing appropriate prognostic functions. In this system a flight control surface is driven by two parallel rollerscrews, on their turn driven by brushless motors equipped with gearhead and clutch; the motors electric drives are controlled by dual redundant electronic units performing closed loop position control as a function of the commands received from the flight control computer. Provisions are taken in the motor drives to provide damping in the event of simultaneous failure of both actuators. The electronic units perform control, diagnosis and prognosis of the actuation system and mutually exchange data via a cross channel data link. System prognosis is made by dedicated algorithms processing the control and feedback signals obtained in flight and during preflight checks. As a whole, a smart mechatronic system is obtained providing high integrity control of an aerodynamic surface with dual mechanical link, dual power source and quadruplex control, similarly to a fly-by-wire hydraulic flight control. The paper first addresses the critical design issues associated with the electromechanical actuation of flight control surfaces, briefly reviews alternative solutions proposed for jam-tolerant electromechanical actuators, then outlines configuration, characteristics and performance of the mechatronic actuation system, and presents a summary of its behaviour under normal, degraded, fault developing and failure conditions.
Assessing Multimedia Content Adaptation Techniques With a View to Using Heterogeneous Handheld Devices in Performing Product Development Tasks
Authors: Opiyo Eliab Z.
Published: October 2013

This paper articulates the potentials and limitations of the existing techniques for adapting product information contents for transmission among heterogeneous terminal devices and networks. The principal aim of the work was to understand, through a literature survey and empirical investigations, the affordances of the existing content adaptation techniques with a view to using handheld devices in performing product development tasks. Specifically, we reviewed and analyzed a wide range of the existing and emerging content adaptation techniques. The review has both revealed the potentials and shortcomings of the prevailing content adaptation strategies, and also has raised several questions for further research. Among the main shortcomings include lack of suitable mechanisms for adapting some specific contents used in product development such as for adapting 3D product models in context; and the inability of the existing mechanisms to guarantee the synchronization of both the meaning and the context of the content among heterogeneous terminal devices whilst meeting both resource constraints and task requirements. We have also identified the characteristic features we expect an ideal content adaptation mechanism to encompass, and used them as the basis for assessing the extents to which the existing techniques meet the adaptation requirements in product development. A concept and a generic architecture for content adaptation in a product development environment have subsequently been proposed. Overall, the existing content adaptation solutions provide only a subset of the desirable functional features. What is needed is a comprehensive adaptation mechanism, which among other things, handles 3D models and other types of product data; guarantees the synchronization of both the context and the meaning of the information content; considers the constraints posed by the heterogeneity of terminal devices and networks, and which at the same time also takes into account the task requirements and the specific needs and preferences of the users (who in the context of the work reported in this paper are the designers and engineers).
Multi-Directional Blending for Heterogeneous Object Modeling
Authors: Ozbolat Ibrahim T. , Koc Bahattin , Deng Yaqin
Published: October 2013

This paper presents a new multi-directional blending technique for heterogeneous object modeling. Contrary to earlier studies, this paper introduces material blending through multiple features with different material composition. Firstly, the Voronoi diagram of multiple-target curves is constructed to generate bisector of the geometric domain. Then, metamorphosis from the generator feature to target features is performed in two steps. First, optimum curve matching between target features and enclosing Voronoi cells is obtained. Then, an optimum ruling line alignment and insertion technique between the Voronoi diagram and generator features is developed. Next, multi-directional material composition is mapped based on a set of relations. The proposed methodologies are implemented and illustrative examples are given in this paper.
Evaluating the Mechanical Properties of Carbon Fiber Reinforced Polymer Matrix Composite Materials at Room and Elevated Temperatures
Authors: Farahikia Mahdi , Macwan Sunilbhai , Delfanian Fereidoon , Hu Zhong
Published: October 2013

A series of tensile, compression and shear tests in room temperature were carried out on carbon fiber reinforced polymer matrix composite materials (IM7/PEEKEK) to evaluate their mechanical properties. Also tensile tests at 160 degrees Fahrenheit (72 degrees Celsius) in longitudinal and transverse directions were done to study the effects of such temperature on the tensile strength of the mentioned composite materials. The setup of the testing equipment and the furnace that was used to provide elevated temperature conditions limited the possibility of conducting compressive and shear tests at high temperature as well as raising the temperature to higher levels. The experiments were set up in accordance with ASTM standards that best corresponded to the test specifications. Specimens were categorized into groups according to their nature of testing. All the specimens were reinforced at both ends by means of tabs which were bonded on both faces to reduce the effects of the external pressure exerted on them through the grips of the testing machines and were tested until failure. Load, elongation (displacement) and strain data were recorded by means of strain gages and data acquisition systems.

The accuracy of the experimental data for the room temperature portion of the experiments is verified by comparing them to those of the most equivalent composite family, as having not been given any information regarding the structural properties and manufacturing processes of the composite materials that were used throughout the experiments made it difficult to find exact ASTM standards and reference materials for the testing and comparison of results.

The results of the experiments showed that the tensile strength of this particular composite material is not effected by the 160 degrees Fahrenheit temperature; a point that is proved by the literature indicating their specific and sensitive application in aircraft heat dissipation [1].
Experimental Investigations on Mixed Flow Impeller and Vane Diffuser Under Various Operating Conditions
Authors: Ramesh Rajakumar D. , Ramamurthy S. , Govardhan M.
Published: October 2013

Experimental Investigations are carried out to study the effect of tip clearance flow in a mixed flow compressor stage. Two configurations, namely; constant and variable clearance gaps between impeller and stationary shroud are considered. For the purpose of the present investigations, a mixed flow compressor stage is designed and fabricated. The flow investigations were carried out in a closed circuit compressor rig. Detailed steady and unsteady measurements were carried out for three clearance gaps, namely; 0.5 mm, 0.75 mm, 0.9 mm. From the experimental investigations it is shown that constant tip clearance configurations show better performance in terms of pressure ratio and efficiency compared to variable clearance configurations. For a given configuration the pressure ratio and efficiency of the stage decrease with increase in the tip gap without indicating any optimum value. Tip clearance flow has considerable effect on the flow through the diffuser and the unsteady flow gets amplified and carried away into the vane diffuser.
Effect of Fiber Form and Volume Fraction on Fiber-Reinforced Biomimicked Composites
Authors: Alghahtani Hussain , Allameh Seyed M.
Published: October 2013

Biomimicked composites have shown to be superior to monolithic structural materials. However, they need reinforcement to replace conventional load-bearing structural composites. Carbon Fibers in long and short forms were used as reinforcement in biomimicked composites. Mechanical tests including four point bending were conducted to determine the effects of form and volume fraction of fibers on the fracture toughness of the biomimicked composites.
Experimental and Numerical Study of Soft Tissue Surrogate Behavior Under Ballistic Loading
Authors: Amborn Ericka K. , Muci-Küchler Karim H. , Hinz Brandon J.
Published: October 2013

Studying the high strain rate behavior of soft tissues and soft tissue surrogates is of interest to improve the understanding of injury mechanisms during blast and impact events. Tests such as the split Hopkinson pressure bar have been successfully used to characterize material behavior at high strain rates under simple loading conditions. However, experiments involving more complex stress states are needed for the validation of constitutive models and numerical simulation techniques for fast transient events. In particular, for the case of ballistic injuries, controlled tests that can better reflect the effects induced by a penetrating projectile are of interest. This paper presents an experiment that tries to achieve that goal. The experimental setup involves a cylindrical test sample made of a translucent soft tissue surrogate that has a small pre-made cylindrical channel along its axis. A small caliber projectile is fired through the pre-made channel at representative speeds using an air rifle. High speed video is used in conjunction with specialized software to generate data for model validation.

A Lagrangian Finite Element Method (FEM) model was prepared in ABAQUS/Explicit to simulate the experiments. Different hyperelastic constitutive models were explored to represent the behavior of the soft tissue surrogate and the required material properties were obtained from high strain rate test data reported in the open literature. The simulation results corresponding to each constitutive model considered were qualitatively compared against the experimental data for a single projectile speed. The constitutive model that provided the closest match was then used to perform an additional simulation at a different projectile velocity and quantitative comparisons between numerical and experimental results were made. The comparisons showed that the Marlow hyperelastic model available in ABAQUS/Explicit was able to produce a good representation of the soft tissue surrogate behavior observed experimentally at the two projectile speeds considered.
Effect of Turbulence and Offset Loading on the Performance of a Single Pad Externally Adjustable Fluid Film Bearing
Authors: Shenoy B. Satish , Pai B. Rammohan S. , Pai B. Raghuvir , Rao D. Shrikanth
Published: October 2013

Paper deals with the effect of turbulence on steady state performance characteristics of an eccentrically loaded 120° single pad externally adjustable fluid film bearing. The bearing has an aspect ratio of one and operates over a wide range of eccentricity ratios and adjustments. Two load-offset positions (β/χ) of 0.45 and 0.55 are considered in the present analysis. Reynolds equation incorporated with the Linearized turbulence model of Ng and Pan is solved numerically using finite difference method. A comparative study predicts that, load capacity of a bearing operating with β/χ = 0.55 and Re = 16000 is superior for negative radial and tilt adjustment configuration of the pad.
Improvement of Corrosion Resistance on a Low Carbon Steel 1018 in 3.5% NaCl Solution by Electrolytic-Plasma-Process (EPP)
Authors: Liang Jiandong , Hossain Naser I. , Wahab Muhammad A. , Guo Shengmin
Published: October 2013

In this paper, a cathodic electrolytic plasma process (EPP) is introduced as a new corrosion prevention method. It is a green and cost-effective method of metal surface treatment. The EPP procedure and the EPP-treated 1018 steel are described in detail. On EPP treated surfaces, a spontaneous pattern due to localized melting and quenching could be obtained. Scanning electron microscopy and energy dispersive X-ray spectroscopy were used to characterize the special surface morphology and chemical patterns on EPP resultant features. Standard corrosion tests were conducted in EPP-treated samples. The corrosion analysis indicates that the EPP treatment could effectively improve the uniform corrosion of 1018 steel in 3.5% NaCl solution. With longer time of EPP treatment (15 minutes), the passivation was significantly extended and hence the localized corrosion resistance is improved. Also, the higher corrosion resistance was found to be sustainable (in 48 hours corrosion test, NaCl solution) on all the EPP treated samples.
Aerodynamics of a Yawed Blade in Reverse Flow
Authors: Lozano Rafael , Raghav Vrishank , Komerath Narayanan
Published: October 2013

The retreating blades of rotorcraft operated at high advance ratios will experience reverse flow through a sector encompassing a wide range of blade azimuth angles. There is a great deal of uncertainty in the blade aerodynamic loads under these conditions. This is a limiting factor when trying to improve the flight speed envelope of helicopters. Previous studies and work have used two-dimensional aerodynamic approaches for the reverse flow area, making the assumption that aerodynamic forces behave similar in magnitude but opposite in direction. There have been no 3-dimensional considerations being taken into account nor was vortex induced lift considered. We hypothesize that the reverse blade flow field includes phenomena similar to the formation of a leading edge vortex on highly-swept, sharp-edges delta wings. An approach is being developed to understand aerodynamic contributions to blade loading beyond linear theory, where vortex-induced lift might be significant. Rotor blades at highly yawed angles relative to the wind can be thought of as very low aspect ratio wings. Since reverse airfoils are thought of as sharp edges, theoretically it should stand that a reverse finite wing at high yawed angles could be considered as a slender delta wing. The main aim of this work is to progress towards testing this above hypothesis. Experimental data is collected from a scaled version of a rotor blade exposed to the reverse flow at various azimuth positions representing the retreating side of the disc, in a 1.07m×1.07m low turbulence wind tunnel.
Evaluation of Adhesive Joints of Two Different Materials
Authors: Islam M. M. , Kapania Rakesh K.
Published: October 2013

In a test-fixture that the authors were using, steel tabs adhesively bonded to an aluminum panel debonded before the design load on the real test panel was fully applied. Therefore, studying behavior of adhesive joints for joining dissimilar materials was deemed to be necessary. To determine the failure load responsible for debonding of adhesive joints of two dissimilar materials, stress distributions in adhesive joints as obtained by a nonlinear finite element model of the test-fixture were studied under a gradually increasing compression-shear load. It was observed that in-plane stresses were responsible for the debonding of the steel tabs. To achieve a better understanding of adhesive joints of dissimilar materials, finite element models of adhesive lap joints and Asymmetric Double Cantilever Beam (ADCB) were studied, under loadings similar to the loading faced by the test-fixture. The analysis was performed using ABAQUS, a commercially available software, and the cohesive zone modeling was used to study the debonding growth.
Design Optimization of a Partial Admitted Supersonic Turbine Using Genetic Algorithm and 3D Numerical Analysis
Authors: Aghaei Tog R. , Tousi A. M. , Boroomand M.
Published: October 2013

In some feeding systems, the supersonic impulse turbines are used when the fluid mass flow is low in order to achieve high specific work. To prevent losses due to low blade aspect ratio and issues related to manufacturing and industrial problems, the turbine is used in partial admission conditions. Studies show that the turbine efficiency is highly dependent on the amount of partial admission coefficient. The turbine efficiency in full admission is high, but the use of partial admission lowers the additional losses. Therefore, there will be a percentage of partial admission in which the turbine will have the highest efficiency. The aim of this work is to achieve the optimum partial admission for a special impulse turbine as a case study. Therefore, in the beginning, an appropriate model of losses is presented. Then, using a nonlinear design optimization code, the partial admission of an impulse supersonic turbine is optimized. This code is written using a genetic algorithm. Then, using three-dimensional numerical analysis, the optimal model will be selected. In the optimization problem, the turbine efficiency is the objective function. The amount of design parameters and constraints used in this process are ten and eight, respectively.
The Oregon State University Mini Malter
Authors: Hortnagl Josef G. , Parmigiani John P.
Published: October 2013

In the past 30 years the growing micro brewing community has stimulated research in the science of brewing beer. The Oregon State University (OSU) food science and crop science departments are resources for such research. There has existed a gap between the two departments that hinders the combination of their work. This gap is the production of malted barley, which is a key ingredient in beer. There currently exists no industry equivalent that can malt a batch size on a scale appropriate for the OSU food science brewery. This factor was the motivation for the mini malter project. This project was a collaborative effort between the schools of mechanical, industrial, manufacturing engineering and food science technology to design and build a prototype malting machine. The design chosen was a round stainless steel vessel for washing, steeping, germinating and kilning. Its main capability is incorporating all the different processes required for malting barley into a single machine. These multiple systems are controlled by a dedicated PC, data acquisition and conditioning hardware, and a custom LabVIEW program. After calibrating to produce malt similar to industry standard the mini malter has become a permanent addition to the food science department. The mini malter has also attracted interest from local brewers and barley farmers.
Estimation of Residual Stresses and Crater Shape in µ-EDM by Finite Element Method
Authors: Mathew Jose , K. Allesu , Srisailam Shravani , Somashekhar K. P. , P. Prakash Naidu , Suvin P. S.
Published: October 2013

Micro-Electric Discharge Machining (μ-EDM) is the process of machining electrically conductive materials in the form of micro-size craters by using precisely controlled sparks that occur between tool electrode and workpiece in the presence of dielectric fluid. The present paper attempts to predict the accurate model for thermal behavior of the EDM process on commercially available Inconel 718. The temperature gradients are crucial in identifying the zones of high temperature and high residual stresses. 3-Dimensional, transient coupled (structural and thermal) analysis is modeled for Inconel 718 workpiece material to estimate the residual stresses due to spark erosion and also to study the crater morphology. The residual stresses are higher at the centre of the crater and it is decreasing when move far from the centre. The simulated results are compared with the experimental results. Both the experimental and the simulated results are in good agreement.