bluuebunny/crossref_metadata_2025 huggingface dataset:
A Comparative and Phylogenetic Study of the Ditylenchus dipsaci, Ditylenchus destructor and Ditylenchus gigas Populations Occurring in Poland
Authors: Jeszke Arnika , Budziszewska Marta , Dobosz Renata , Stachowiak Anna , Protasewicz Dorota , Wieczorek Przemyslaw , Obrępalska‐Stęplowska Aleksandra
Published: August 2013

The genus Ditylenchus contains more than 80 recognized nematode species with a very wide host range. The most serious species are Ditylenchus dipsaci and Ditylenchus destructor. Populations of D. dipsaci species complex were collected from Allium cepa, Cichorium endivia and Phlox paniculata in Poland. The Ditylenchus gigas population was collected from Vicia faba minor, and populations of D. destructor, from Solanum tuberosum spp. tuberosum. Analyses of the rDNA sequences spanning both ITS1 and ITS2 fragment regions were carried out on the collected populations. The obtained DNA sequences were compared with those DNA sequences deposited in GenBank of populations isolated in other countries. Phylogenetic analysis was performed using the data obtained from the DNA sequence comparisons. The results indicated that there is no clear distinction between European and non‐European populations within D. dipsaci. The results also showed no clear distinction between populations isolated from different host plant species, including populations found in Poland. The populations of D. destructor described here constitute a common group together with American and Chinese populations belonging to the haplotype C of the D. destructor species. On the other hand, the D. gigas population was localized separately from those populations that have been described up until now, from Europe and Africa. This is also the first report on the occurrence of D. gigas in Poland.
Control of Colletotrichum coccodes on Tomato by Grafting and Soil Amendments
Authors: Gilardi Giovanna , Colla Paola , Pugliese Massimo , Baudino Michele , Gullino Maria Lodovica , Garibaldi Angelo
Published: August 2013

Eight trials were carried out in 2011 and 2012 in Northern Italy to evaluate the efficacy of grafting, compost and biofumigation with Brassica carinata against Colletotrichum coccodes on tomato. Four trials were carried out in commercial farms, and four trials were carried out in plastic tunnels at an experimental centre. The rootstocks ‘Armstrong’, ‘Arnold’, ‘Beaufort’, ‘Big Power’, ‘Brigeor’, ‘Emperador’, ‘King Kong’, ‘Spirit’ and ‘Superpro V295’ were tested. Host plants included several tomato F1 hybrids: ‘Amantino’, ‘Arawak’, ‘CLX 37438’, ‘Cauralina’, ‘CU 8301’, ‘CU 8506’, ‘DRK 7021’, ‘E 34431’, ‘E 50070’, ‘EXP’, ‘Gotico’, ‘Ingrid’, ‘ISI 61401’, ‘ISI 61402’, ‘Profitto’, ‘Punente’, ‘Rugantino’ and ‘Tomahawk’. Tomato roots from the control plots were 34 to 87% diseased in both naturally and artificially infested soil. Among the nineteen commercial tomato hybrids tested, in the presence of a very high disease pressure in a naturally infested soil, ‘Rugantino’ was the least affected by C. coccodes, showing 32% infected roots. ‘Tomahawk’ grafted onto ‘Arnold’, ‘Armstrong’ and ‘Superpro V295’ was significantly less affected by C. coccodes, while ‘Arawak’ grafted onto ‘Armstrong’, ‘Arnold’, ‘Emperador’ and ‘Beaufort’ provided very good control of root rot in the different trials. Compost addition and biofumigation with Brassica pellets were also tested with and without grafting. Soil amendment with compost, in the case of the ‘Arawak’ and ‘Tomahawk’, resulted in a slightly improved disease control only on non‐grafted plants. When grafting and biofumigation were combined in a soil naturally infested with C. coccodes and Meloidogyne arenaria, biofumigation did not improve C. coccodes control in comparison with grafting alone. In a naturally infested soil, compost alone and combined with biofumigation improved disease control only on non‐grafted ‘Tomahawk’ plants. In general, grafting by itself provided very good results in terms of disease control, which were not significantly improved by combination with compost and/or biofumigation.
Identification and Analysis of Resistance‐like Genes in the Tomato Genome
Authors: Ni Xiaoxun , Yang Jingjing , Sun Silong , Yang Wencai
Published: August 2013

Tomato (Solanum lycopersicum L.) is one of the most important vegetable crops in the world. However, the tomato production is severely affected by many diseases. The use of host resistance is believed to be the most effective approach to control the pathogens. In this study, a total of 1003 resistance‐like genes were identified from the tomato genome using individual full‐length search and conserved domain verification approach. Of the predicted resistance genes, serine/threonine protein kinase was the largest class with 384 genes followed by 212 genes encoding receptor‐like kinase, 107 genes encoding receptor‐like proteins, 68 genes encoding coiled‐coil–nucleotide‐binding site (NBS)–leucine‐rich repeat (LRR) and 19 genes encoding Toll interleukin‐1 receptor domain‐NBS‐LRR. Physical map positions established for all predicted genes using the tomato WGS chromosomes SL2.40 information indicated that most resistance‐like genes clustered on certain chromosomal regions. Comparisons of the sequences from the same resistance‐like genes in S. pimpinellifolium and S. lycopersicum showed that 93.5% genes contained single nucleotide polymorphisms and 19.7% genes contained insertion/deletion. The data obtained here will facilitate isolation and characterization of new resistance genes as well as marker‐assisted selection for disease resistance breeding in tomato.
Wage Rigidities in an Estimated Dynamic, Stochastic, General Equilibrium Model of the UK Labour Market
Authors: Faccini Renato , Millard Stephen , Zanetti Francesco
Published: August 2013

We estimate a New Keynesian model with matching frictions and nominal wage rigidities on UK data. We show that in a model with matching frictions, whether nominal wage rigidities are relevant or irrelevant for inflation dynamics depends on the parametrization. At the estimated equilibrium, we find that wage rigidities are irrelevant, despite improving the empirical performance of the model. The reason is that with matching frictions, marginal costs depend on unit labour costs and on an additional component related to search costs. Wage rigidities affect both components in opposite ways leaving marginal costs and inflation virtually unaffected.
Gene expression patterns associated with caste and reproductive status in ants: worker‐specific genes are more derived than queen‐specific ones
Authors: Feldmeyer B. , Elsner D. , Foitzik S.
Published: August 2013

Variation in gene expression leads to phenotypic diversity and plays a central role in caste differentiation of eusocial insect species. In social Hymenoptera, females with the same genetic background can develop into queens or workers, which are characterized by divergent morphologies, behaviours and lifespan. Moreover, many social insects exhibit behaviourally distinct worker castes, such as brood‐tenders and foragers. Researchers have just started to explore which genes are differentially expressed to achieve this remarkable phenotypic plasticity. Although the queen is normally the only reproductive individual in the nest, following her removal, young brood‐tending workers often develop ovaries and start to reproduce. Here, we make use of this ability in the ant Temnothorax longispinosus and compare gene expression patterns in the queens and three worker castes along a reproductive gradient. We found the largest expression differences between the queen and the worker castes (~2500 genes) and the smallest differences between infertile brood‐tenders and foragers (~300 genes). The expression profile of fertile workers is more worker‐like, but to a certain extent intermediate between the queen and the infertile worker castes. In contrast to the queen, a high number of differentially expressed genes in the worker castes are of unknown function, pointing to the derived status of hymenopteran workers within insects.
NtProRP1, a novel proline‐rich protein, is an osmotic stress‐responsive factor and specifically functions in pollen tube growth and early embryogenesis in Nicotiana tabacum
Authors: CHEN JUNYI , ZHAO JING , NING JUE , LIU YUAN , XU JING , TIAN SHUJUAN , ZHANG LIYAO , SUN MENG‐XIANG
Published: August 2013

Proline‐rich proteins (PRPs) are known to play important roles in sexual plant reproduction. Most of the known proteins in the family were found in styles or pollen and modulate pollen tube growth. Here, we identified a novel member of the gene family, NtProRP1, which is preferentially expressed in tobacco pollen grains, pollen tubes and zygotes. NtProRP1 could be secreted into the extracellular space including the cell wall, and the predicted N‐terminal signal peptide is crucial for its secretion. In NtProRP1‐RNAi plants, pollen germination and pollen tube growth were significantly slower and showed zigzag or swell morphology in vitro. Early embryogenesis also exhibited aberrant development, indicative of its critical role in both pollen tube growth and early embryogenesis. Further investigation revealed that NtProRP1 plays a crucial role in osmotic stress response during pollen tube growth and is likely regulated by Tsi, a stress‐responsive gene, suggesting that the regulatory mechanism is also involved in the stress response during sexual plant reproduction. These data provide evidence that NtProRP1 functions as a downstream factor of Tsi1 in the stress response and converges the stress signal into the modulation of pollen tube growth and early embryogenesis.
Perinatal factors in patent ductus arteriosus in very low‐birthweight infants
Authors: Chen Ying‐Yao , Wang Hsiao‐Ping , Chang Jenn‐Tzong , Chiou Yee‐Hsuan , Huang Yung‐Feng , Hsieh Kai‐Sheng ,   Taiwan Premature Infant Development Collaborative Study Group
Published: August 2013

Background

The relationship between hemoglobin and patent ductus arteriosus (PDA) has not been discussed before. The aim of this study was to assess the influence of hemoglobin and perinatal factors on PDA in very low‐birthweight (VLBW) infants.

Methods

Using data from the Premature Baby Foundation of Taiwan (PBFA), the characteristics, perinatal factors, and hemoglobin of VLBW infants with and without PDA and treatment were compared.

Results

Between January 2008 and December 2010, 89 VLBW infants were admitted to hospital. The overall survival rate was 87.6%. Twelve infants were excluded. Compared to those without PDA, the 34 infants with PDA received oral indomethacin or surgery, had smaller mean gestational age (GA; 27.93 ± 1.818 weeks, P = 0.000003), lower mean birthweight (BW; 1031 ± 259 g, P = 0.0001), significantly lower Apgar score at 5 min, more severe respiratory distress syndrome (RDS; grade 3 or 4), greater use of surfactants, and lower mean hemoglobin (P = 0.018) after birth than those without PDA. Compared to those with indomethacin, the seven infants with surgery had lower mean GA (26.43 ± 1.718 weeks, P = 0.011), significantly lower Apgar scores at 1 min, but higher platelet count (P = 0.002) after birth, and more red blood cell transfusions (P = 0.039).

Conclusions

Smaller GA, lower BW, lower Apgar score at 5 min, more severe RDS, greater use of surfactants, and lower hemoglobin after birth place VLBW infants at greater risk of PDA. Proper prenatal care, and prevention of premature labor and delivery may be the most important preventative factors. The appropriate hemoglobin level for PDA closure requires further investigation.
Association of problem behavior with sleep problems and gastroesophageal reflux symptoms
Authors: Sakaguchi Katsuyoshi , Yagi Takakazu , Maeda Aya , Nagayama Kunihiro , Uehara Sawako , Saito‐Sakoguchi Yoko , Kanematsu Kyoko , Miyawaki Shouichi
Published: August 2013

Background

There are few large‐scale epidemiologic studies examining the associations between sleep problems, gastroesophageal reflux disease (GERD) symptoms, lifestyle and food habits and problem behaviors (PB) in adolescents. The aim of this study was to evaluate the associations among these factors in Japanese adolescents.

Methods

A cross‐sectional survey of 1840 junior high school students was carried out using questionnaires. The subjects were classified into PB or normal behavior (NB) groups using the Pediatric Symptom Checklist (PSC). The scores of the sleep‐related factors, sleep bruxism, lifestyle and food habits, and GERD symptoms were compared. Logistic regression analysis was used to determine the factors related to PB.

Results

Mean subject age was 13.3 ± 1.8 years. The PB group had significantly longer sleep latency and higher GERD symptom score (P < 0.001). Furthermore, the PB group was significantly more likely to experience absence of the mother at dinner time, skip breakfast, and have <30 min of conversation among family at dinner time. The PB group had significantly higher frequencies of sleep bruxism, difficulty falling asleep within 30 min, nightmares, feeling of low sleep quality, daytime somnolence, and daytime lack of motivation. Feelings of low sleep quality had the strongest association with PB, with an adjusted odds ratio of 12.88 (95% confidence interval: 8.99–18.46).

Conclusions

PB in adolescents are associated with sleep problems, including sleep bruxism, as well as lifestyle and food habits and GERD symptoms.
Fluid–rock interactions associated with regional tectonics and basin evolution
Authors: Fontana Simone , Nader Fadi Henri , Morad Sadoon , Ceriani Andrea , Al‐Aasm Ihsan Shakir , Daniel Jean‐Marc , Mengus Jean‐Marie
Published: August 2013

An integrated approach consisting of fracture analysis, petrography, carbon, oxygen and strontium‐isotope analyses, as well as fluid‐inclusion micro‐thermometry, led to a better understanding of the evolution of fluid–rock interactions and diagenesis of the Upper Permian to Upper Triassic carbonates of the United Arab Emirates. The deposited carbonates were first marked by extensive early dolomitization. During progressive burial, the carbonates were affected by dolomite recrystallization as well as precipitation of vug and fracture‐filling dolomite, quartz and calcite cements. After considerable burial during the Middle Cretaceous, sub‐vertical north–south oriented fractures (F1) were cemented by dolomite derived from mesosaline to hypersaline fluids. Upon the Late Cretaceous maximum burial and ophiolite obduction, sub‐vertical east–west fractures (F2) were cemented by dolomite (Dc2) and saddle dolomite (Ds) derived from hot, highly saline fluids. Then, minor quartz cement has precipitated in fractures from hydrothermal brines. Fluid‐inclusion analyses of the various diagenetic phases imply the involvement of increasingly hot (200°C) saline brines (20 to 23% NaCl eq.). Through one‐dimensional burial history numerical modelling, the maximum temperatures reached by the studied rocks are estimated to be in the range of 160 to 200°C. Tectonically‐driven flux of hot fluids and associated diagenetic products are interpreted to have initiated during the Late Cretaceous maximum burial and lasted until the Oligocene–Miocene compressional tectonics and related uplift. The circulation of such hydrothermal brines led to partial dissolution of dolomites (Dc2 and Ds) and to precipitation of hydrothermal calcite C1 in new (mainly oriented north–south; F3) and pre‐existing, reactivated fractures. The integration of the obtained data confirms that the diagenetic evolution was controlled primarily by the interplay of the burial thermal evolution of the basin and the regional tectonic history. Hence, this contribution highlights the impacts of regional tectonics and basin history on diagenetic processes, which may subsequently affect reservoir properties.
Detectable urogenital schistosome DNA and cervical abnormalities 6 months after single‐dose praziquantel in women with Schistosoma haematobium infection
Authors: Downs Jennifer A. , Kabangila Rodrick , Verweij Jaco J. , Jaka Hyasinta , Peck Robert N. , Kalluvya Samuel E. , Changalucha John M. , Johnson Warren D. , van Lieshout Lisette , Fitzgerald Daniel W.
Published: August 2013

We explored response to single‐dose praziquantel therapy in a cohort of 33 women with Schistosoma haematobium infection in rural Mwanza, Tanzania. Women with S. haematobium infection confirmed both by eggs in urine and by polymerase chain reaction (PCR) received single‐dose praziquantel and treatment of concomitant sexually transmitted infections. Macroscopic cervical abnormalities were also quantified. After 6 months, microscopically detectable egg excretion was eliminated, but 8 of 33 women (24%) were persistently positive for S. haematobium by PCR, and 11 (33%) had cervical abnormalities potentially attributable to schistosomiasis. This suggests that praziquantel treatment more frequently than every 6 months may be necessary for complete elimination of the parasite and prevention of genital tissue pathology. This aggressive therapy may in turn play a key role decreasing HIV susceptibility in millions of people living in regions in which S. haematobium is endemic.
Getting antimalarials on target: impact of national roll‐out of malaria rapid diagnostic tests on health facility treatment in three regions of Tanzania
Authors: Bruxvoort Katia , Kalolella Admirabilis , Nchimbi Happy , Festo Charles , Taylor Mark , Thomson Rebecca , Cairns Matthew , Thwing Julie , Kleinschmidt Immo , Goodman Catherine , Kachur S. Patrick
Published: August 2013

Objectives

Parasitological confirmation of malaria prior to treatment is recommended for patients of all ages, with malaria rapid diagnostic tests (mRDTs) an important tool to target artemisinin‐based combination therapies (ACTs) to patients with malaria. To evaluate the impact on case management practices of routine government implementation of mRDTs, we conducted large‐scale health facility surveys in three regions of Tanzania before and after mRDT roll‐out.

Methods

Febrile patients at randomly selected health facilities were interviewed about care received at the facility, and blood samples were collected for reference blood smears. Health facility staff were interviewed about their qualifications and availability of malaria diagnostics and drugs.

Results

The percentage of febrile patients tested for malaria at the facility increased from 15.8% in 2010 to 54.9% in 2012. ACTs were obtained by 65.8% of patients positive by reference blood smear in 2010 and by 50.2% in 2012 (P = 0.0675); no antimalarial was obtained by 57.8% of malaria‐negative patients in 2010 and by 82.3% in 2012 (P < 0.0001). Overall, ACT use decreased (39.9–21.3%, P < 0.0001) and antibiotic use increased (31.2–48.5%, P < 0.0001).

Conclusion

Roll‐out of mRDTs in Tanzania dramatically improved diagnostic testing for malaria and reduced overuse of ACTs for patients without parasitemia. However, post–roll‐out almost 50% of febrile patients did not receive a diagnostic test, and almost 50% of patients testing positive did not receive ACTs. Stock‐outs of ACTs and mRDTs were important problems. Further investigation is needed to determine reasons for not providing ACTs to patients with malaria and potential for inappropriate antibiotic use.
Resistance gene enrichment sequencing (RenSeq) enables reannotation of the NB‐LRR gene family from sequenced plant genomes and rapid mapping of resistance loci in segregating populations
Authors: Jupe Florian , Witek Kamil , Verweij Walter , Śliwka Jadwiga , Pritchard Leighton , Etherington Graham J. , Maclean Dan , Cock Peter J. , Leggett Richard M. , Bryan Glenn J. , Cardle Linda , Hein Ingo , Jones Jonathan D.G.
Published: August 2013

RenSeq is a NB‐LRR (nucleotide binding‐site leucine‐rich repeat) gene‐targeted, Resistance gene enrichment and sequencing method that enables discovery and annotation of pathogen resistance gene family members in plant genome sequences. We successfully applied RenSeq to the sequenced potato Solanum tuberosum clone DM, and increased the number of identified NB‐LRRs from 438 to 755. The majority of these identified R gene loci reside in poorly or previously unannotated regions of the genome. Sequence and positional details on the 12 chromosomes have been established for 704 NB‐LRRs and can be accessed through a genome browser that we provide. We compared these NB‐LRR genes and the corresponding oligonucleotide baits with the highest sequence similarity and demonstrated that ~80% sequence identity is sufficient for enrichment. Analysis of the sequenced tomato S. lycopersicum ‘Heinz 1706’ extended the NB‐LRR complement to 394 loci. We further describe a methodology that applies RenSeq to rapidly identify molecular markers that co‐segregate with a pathogen resistance trait of interest. In two independent segregating populations involving the wild Solanum species S. berthaultii (Rpi‐ber2) and S. ruiz‐ceballosii (Rpi‐rzc1), we were able to apply RenSeq successfully to identify markers that co‐segregate with resistance towards the late blight pathogen Phytophthora infestans. These SNP identification workflows were designed as easy‐to‐adapt Galaxy pipelines.
An integrative model of the control of ovule primordia formation
Authors: Galbiati Francesca , Sinha Roy Dola , Simonini Sara , Cucinotta Mara , Ceccato Luca , Cuesta Candela , Simaskova Maria , Benkova Eva , Kamiuchi Yuri , Aida Mitsuhiro , Weijers Dolf , Simon Rüdiger , Masiero Simona , Colombo Lucia
Published: August 2013

Upon hormonal signaling, ovules develop as lateral organs from the placenta. Ovule numbers ultimately determine the number of seeds that develop, and thereby contribute to the final seed yield in crop plants. We demonstrate here that CUP‐SHAPED COTYLEDON 1 (CUC1), CUC2 and AINTEGUMENTA (ANT) have additive effects on ovule primordia formation. We show that expression of the CUC1 and CUC2 genes is required to redundantly regulate expression of PINFORMED1 (PIN1), which in turn is required for ovule primordia formation. Furthermore, our results suggest that the auxin response factor MONOPTEROS (MP/ARF5) may directly bind ANT, CUC1 and CUC2 and promote their transcription. Based on our findings, we propose an integrative model to describe the molecular mechanisms of the early stages of ovule development.
Segmentation of the mouse fourth deep lumbrical muscle connectome reveals concentric organisation of motor units
Authors: Hirst Theodore C. , Ribchester Richard R.
Published: August 2013

Key points

An accelerated image segmentation algorithm was developed and applied to analysis of motor unit arborisation and connectivity (the ‘connectome’) in fourth deep lumbrical muscles (4DL) of mice expressing fluorescent proteins as morphological reporters.

Mouse 4DL muscles contain between 4 and 9 motor units and motor unit size in these muscles ranged from 3 to 111 muscle fibres.

Small motor units were restricted in their arbors to the vicinity of the nerve entry point. Larger motor units concentrically occupied muscle fibres located progressively further from the nerve entry point.

Motor unit size was weakly correlated with motor endplate size, suggesting a hierarchy of motor unit sizes based on synaptic strength.

The data suggest a segregated organisation of motor units in cylindrical muscles that has not previously been appreciated and indicate the direction of future studies required to establish possible relationships between the strengths of synaptic connections and motor unit size.

Abstract  Connectomic analysis of the nervous system aims to discover and establish principles that underpin normal and abnormal neural connectivity and function. Here we performed image analysis of motor unit connectivity in the fourth deep lumbrical muscle (4DL) of mice, using transgenic expression of fluorescent protein in motor neurones as a morphological reporter. We developed a method that accelerated segmentation of confocal image projections of 4DL motor units, by applying high resolution (63×, 1.4 NA objective) imaging or deconvolution only where either proved necessary, in order to resolve axon crossings that produced ambiguities in the correct assignment of axon terminals to identified motor units imaged at lower optical resolution (40×, 1.3 NA). The 4DL muscles contained between 4 and 9 motor units and motor unit sizes ranged in distribution from 3 to 111 motor nerve terminals per unit. Several structural properties of the motor units were consistent with those reported in other muscles, including suboptimal wiring length and distribution of motor unit size. Surprisingly, however, small motor units were confined to a region of the muscle near the nerve entry point, whereas their larger counterparts were progressively more widely dispersed, suggesting a previously unrecognised form of segregated motor innervation in this muscle. We also found small but significant differences in variance of motor endplate length in motor units, which correlated weakly with their motor unit size. Thus, our connectomic analysis has revealed a pattern of concentric innervation that may perhaps also exist in other, cylindrical muscles that have not previously been thought to show segregated motor unit organisation. This organisation may be the outcome of competition during postnatal development based on intrinsic neuronal differences in synaptic size or synaptic strength that generates a territorial hierarchy in motor unit size and disposition.
Preparing for Generation Z: The Hippocampus Experiment at Ecole Centrale de Nantes
Authors: Evain Christine , Carolan Simon , Magnin Morgan
Published: August 2013

Although social researchers who have written about Generation Z have found it difficult to classify the generation precisely, “Gen Z” is generally defined as the younger children of Generation X — in other words, Gen Z starts with today’s teenagers.

For the last fifteen years, technoculture theorists have been exploring the consequences of the wide availability of internet connectivity to the first generation of people born to it, who are referred to as “Digital Natives”. Their purpose is to address issues such as shifts in the concept of identity, privacy, content creation, activism, and piracy.

Our objective will be to apply the findings of generational experts to highlight possible avenues for pedagogical innovation in our University of science and engineering. We cover a range of questions:

What are the online behavioral differences between generation X, Y and Z?

What is our experience at ECN in terms of blended teacher and student driven pedagogies?

What is the role of Information and Communication Technologies (ICT) in education?

What are the expectations and contributions of the “Digital Natives” likely to be?

Our purpose will be to define the type pedagogical approach which has the potential to appeal to Gen Z and help them face the challenges of their generation.

This paper will be based on the research and testimonies of a wide range of experts: it will include the work of technoculture theorists such as John Palfrey, Urs Gasser and Cathy Davidson as well as our own practical experience at ECN, mainly the Hippocampus project.

Our purpose will be to determine how we — researchers and pedagogues — can draw on our present pedagogical experiences to prepare for generation Z1.
Feed Forward Control for Pneumatic Forearm Prosthesis, Manipulator
Authors: Andrieu Antoine , Tsujiuchi Nobutaka , Koizumi Takayuki , Maeda Sho , Nakamura Yoichiro
Published: August 2013

In order to reach a better productivity in numerous fields, robots have been wildly used for automatic tasks. The main issue of a robot is his lack of adaptability, which is one of the most important ability of human beings. The best tool for adaptability is the human hand. Using pneumatic actuators to drive a robot forearm grants the possibility to move light articles with accuracy and without harming it. It is then necessary to develop accurate model of the different types of actuators. As every human muscle are simulated by those actuators, the size of these must vary and so their properties as well. These artificial muscle-type pneumatic actuators are composed of a rubber balloon, a net, a feeding channel and finally two anchors at both end of the net. Starting with the simplest linear model, we increased the complexity of the model to finally obtain a powerful control of the plastic muscle. To obtain the data we needed for the model, we used a test bench for pneumatic actuators and adjust it to fit the new size of the current actuator. The main difficulty to control the actuator is to find a way to overcome its hysteresis cycle. Then once the model is ready we need to use it to control the different part of the pneumatic forearm. The previous wrist and hand control is enhanced by feed forward control and can perform motion with a great accuracy. The hand can therefore be used without any electronic devices on it and remains lighter and safer. Previous starting dead-zone has been understood and avoided.
Gear Rattle Analysis Based on Wavelet Signal Decomposition
Authors: Brancati R. , Rocca E. , Savino S. , Farroni F.
Published: August 2013

The “gear rattle” phenomenon is a research topic of great interest for the NVH (Noise, Vibration and Harshness) automotive sector, concerning driveline noise and vibrations coming from the manual gear boxes. It is due to the internal combustion engine variable torque producing impacts and rebounds, and consequently noise, between the teeth of the unloaded gear pairs of the gear box because of the unavoidable presence of backlashes.

Discrete Wavelet Transform (DWT) is used to decompose the angular relative motion signal and the wavelet decomposition details are adopted to analyze the dynamic behaviour of gears under rattle conditions. The DWT has been chosen because it is a particularly suitable instrument to recognize discontinuities, such as jumps or instantaneous changes in the slope of the signals, due to their localization in the time domain. Wavelet analysis allows to characterize an event by the localization, the kind, and the amplitude of the event. This technique enables, moreover, to define new indices for metrics of gear rattle especially useful in order to conduct comparisons among different operative conditions. Some examples of application of the proposed technique are reported in the paper. The theoretical investigations regard comparative analysis with respect to the amplitude and to the frequency of speed fluctuations and to the gears lubrication regime.
Trajectory Generation for High Speed Pick and Place Robots
Authors: Barnard Cornelius J. , Briot Sébastien , Caro Stéphane
Published: August 2013

Currently parallel robots are finding more and more acceptance in high-speed pick-and-place operations. As for all high-speed mechanisms, vibratory phenomena appear and deteriorate accuracy and dynamic performance at the terminal positions of the pick-and-place path. This paper aims to evaluate the effectiveness of several pick-and-place trajectories in terms of vibration reduction. To address this problem, an elastodynamic model of a five bar mechanism is developed and its behaviour is simulated as it traverses each trajectory. Spectral analysis of the vibrations allows the quality of the vibration reduction to be quantified. The results show that the first and second natural frequencies of the system are excited. It is also shown that long cycle times with smooth motion profiles improve residual error norms, but are outperformed by their discontinuous counterparts when short cycle times are imposed.
Analysis of the Dynamic Performance of Serial 3R Orthogonal Manipulators
Authors: Nguyen Dinh Quan , Briot Sébastien , Wenger Philippe
Published: August 2013

Serial 3R orthogonal manipulators have been studied recently and it has been proved that they can exhibit good performances in term of workspace size and kinematic properties. The aim of this work is to analyze their dynamic performances, and compare them with anthropomorphic manipulators, which are very popular in industry.

Static and dynamic analyses based on the evaluation of the maximal input torques required for moving the manipulator are achieved. It is shown that, as in kinematics, the dynamic performances of the serial 3R orthogonal manipulators are better.
Elasto-Dynamic Model of Robotic Milling Process Considering Interaction Between Tool and Workpiece
Authors: Bondarenko D. , Pashkevich A. , Briot S. , Ritou M. , Furet B.
Published: August 2013

In this paper, a reduced elasto-dynamic model of the robotic based milling process is presented. In contrast to previous works, it takes into account the interaction between the milling tool and the workpiece that depends on the end-effector position, process parameters and cutting conditions (spindle rotation, feed rate, geometry of the tool, etc.). To reduce the dimension of the problem, the robot dynamics is described as an equivalent mass-spring-damper system with six dimensions. This approach, based on the Rayleigh-Ritz approximation, aims at decreasing computational cost and at avoiding inaccuracy due to ill-conditioning in the full size model. To achieve a realistic modeling of the milling process, the machining efforts due to the interaction between robot, tool and working material are introduced into the robot model and calculated at each time instant. Using this global model that integrates the robot dynamics and the milling process particularities, it is possible to obtain the movement of the robot end-effector and corresponding quality of the final product (profile, macro geometry, etc.). In addition, this model allows selecting the best process parameters and avoiding the vibratory behavior of this machining system which can dramatically affect the milling quality.

The developed model is applied to the behavior analysis of KUKA KR270 robot used for milling applications. This allows finding acceptable range for robot motion profile parameters.
New Interpretation of the Electrical Resistivity Measurements for Obtaining NiTi SMA Stress-Free Transformation Temperatures
Authors: Urbina Cristina , De la Flor Silvia , Gispert-Guirado Francesc , Ferrando Francesc
Published: August 2013

The objective of this study is to clarify and to improve the interpretation of the ER measurements used to obtain NiTi SMA stress-free transformation temperatures for the austenite to martensite transformation process. To achieve this objective, the transformation temperatures of NiTi SMA wires are measured by ER using the Ling and Kaplow interpretation and are compared and complemented by weight fraction diagrams. The weight fractions are obtained from XRD profiles using the Parametric Rietveld refinement and adequate software. As a result of comparing both techniques, a new interpretation of the ER curves is proposed. This new interpretation is based on the shape of NiTi ER curve, which depends on the quantity of R-phase in the NiTi SMA. The quantity of the R-phase is obtained by weight fraction diagrams. According to the findings presented here, a new criterion for R-phase and martensite transformation temperatures is proposed.
For a Sustainable Dialogue: The Green-Use (GU) Learning Cycles Concept
Authors: Serna-Mansoux Livier , Millet Dominique , Chapotot Emilie , Minel Stéphanie
Published: August 2013

Product design is now driven to the satisfaction of requirements all along the life cycle of the product, with an increased concern in environmental impact. A new concept, the Green-Use (GU) Learning Cycles, is proposed. It is used to determine the way a continuous, adaptive interaction between user and product can be established to improve environmental performance during use. It is structured by two levels of analysis (macro and micro) and a cyclic nature. These levels are the “Incremental user involvement levels”, and the “Environmental Impact in Use”. They are modelled around the notion of an evolution in cycles, from the initial state of the system product-user to a final stage which results in optimal use with minimal environmental impact. This work includes experimentation to support the new concept proposed, as well a method to use it.
The Significance of Powertrain Characteristics on the Chatter of Racing Motorcycles
Authors: Cossalter Vittore , Lot Roberto , Massaro Matteo
Published: August 2013

The chatter of motorcycles is a self-excited vibration that may appear during braking. This vibration can be very strong and the accelerations of both the rear and front unsprung masses can reach 5–10g with frequencies in the range 17–22Hz, seriously hindering the rider’s control of the vehicle. Very few studies exist on this topic, and the first work that compares experimental data to numerical simulation and addresses the fundamental mechanisms of the chatter genesis has been recently published. In the current paper authors present the continuation of the research, and in particular the results of a parametric analysis performed to identify the most important design and motion parameters when it comes to chatter stability. The analysis is carried out by simulating chatter with a validated nonlinear motorcycle multibody model which captures the most important vehicle features.
A Multibody System Approach to Drill String Dynamics Modeling
Authors: Pogorelov Dmitry , Mikheev Gennady , Lysikov Nikolay , Ring Lev , Gandikota Raju , Abedrabbo Nader
Published: August 2013

The selection of optimal operational parameters for drilling oil and gas wells is a complex dynamic problem that depends on multiple parameters. Numerous physical and mechanical processes such as rock cutting, friction, hydraulics, and different modes of vibrations, occur during drilling, which should be accounted for in numerical models. It is widely accepted that bottom hole assembly (BHA) vibrations are the primary source of drilling equipment premature failure. Over the last 30 years, progress of computational sciences has enabled the use of numerical simulations of drillstring dynamics as a useful tool to understand and mitigate sources of harmful vibrations. The majority of these models have been based on nonlinear finite elements. There are several significant limitations with this approach, including an extremely high number of degree of freedom (DOF) required to represent geometries with 105 ratio of axial to lateral dimensions and also the complexity of modeling variable contacts in bifurcating systems. While it is relatively new for simulating drilling dynamics, the advantage of the proposed rigid-flexible multibody system approach has been proven for modeling complex dynamic systems in other industries. Using a rigid-flexible multibody system approach to analyze dynamic effects both in frequency and time domains, dynamic modeling of BHA and drillstring is proposed.

Drillstring is simulated as a set of uniform flexible beams connected via linear viscous-elastic force elements. Each beam can undergo arbitrary large displacements as absolutely rigid body, but its flexible displacements due to elastic deformations are small. A method of floating frame of reference for flexible bodies and component mode synthesis is used for modeling beams dynamics. Parameters of the coupling force elements are calculated automatically based on stiffness and inertia characteristics of the connected beams.

This paper discusses the development of the rigid-flexible multibody system for modeling drillstring dynamics and the influence of model parameters on simulation accuracy and calculation time.

A close match is shown between theoretical and numerical results for static and buckling problems as well as resonant frequency values. Several transient drillstring dynamics problems are analyzed for wellbores with uniform diameter. Examples of the analysis of resonant conditions during drilling planning stage are also presented. It is also shown how transient time domain analysis can provide further insights into lateral and torsional vibrations, whirl behavior, and effect of local wellbore curvatures on the drillstring performance.
Wear Simulation of Metal on Metal Hip Replacements: An Analytical Approach
Authors: Mattei Lorenza , Di Puccio Francesca , Ciulli Enrico
Published: August 2013

Hip replacement failure is mainly attributable to the implant wear. Consequently preclinical wear evaluations are extremely important. As experimental tests are attractive but highly cost/time demanding, several predictive models have been proposed mainly based on finite element simulations and for metal on plastic (MoP) implants. The aim of this study is to develop a mathematical wear model of metal on metal prostheses, revision of the previous one for MoP implants, developed by the same authors. The model, based on the Archard wear law and on the Hertzian theory, was applied to compare a total (THR) and a resurfacing (RHR) hip replacement under both in vivo and in vitro gait conditions. The results were in agreement with the literature predicting wear rates significantly higher for the RHR than for the THR. The effect of the boundary conditions on wear rates/maps was also investigated and the model limitations discussed.
Design for Manufacture Using Functional Analysis and CAD Mould Simulation for Rapid Prototyping and Rapid Tooling
Authors: Lupeanu Mihaela E. , Brooks Hadley , Rennie Allan E. W. , Celik H. Kursat , Neagu Corneliu , Akinci Ibrahim
Published: August 2013

The pressure of time, quality and cost, together with increasing product variety, more customised products and worldwide competition is driving technology development and implementation in the area of Rapid Manufacturing (RM). Traditionally, the manufacture of tooling for both prototype parts and production components represents one of the longest and most costly phases in the development of most new products. The cost and time implications of the tooling process are particularly problematic for low-volume products aimed at niche markets, or alternatively for rapidly changing high-volume products.

Rapid Prototyping (RP) and Rapid Tooling (RT) have the potential to dramatically shorten the time required to produce functional prototypes or products. Functional Analysis (FA) plays a key role in the design process of the actual tools, allowing for innovative solutions that can be achieved with RP and RT.

This paper presents a FA methodology to design for manufacture (DFM) based on RP- and RT-specific characteristics, aimed at improving process efficiency, streamline energy consumption, use of volume material, usage of structural innovative lightweight materials, decrease overall costs and improve product quality. Design for Rapid Manufacturing (DFRM) allows for geometric freedom, leading to changes of the overall design process, thus enhancing the FA process. FA begins with stating the need, in a DFRM case that translates into diagnosis, the determination of the manufacturability of the present product and comparison with similar products on the market. Setting objectives, in terms of production costs, quality, flexibility, risk, lead-time, efficiency, and environment are other milestones in FA. Actual function definition involves defining the main functions of the product and their interactions. Clarifying the evaluation parameters, setting criteria levels and technical dimensioning is done for each of the main product functions. The conceptual design process then follows a top-down sequence: corporate, family, structural and component levels. Evaluation and selection of the optimal concept resulting from the FA consists of assessing the manufacturability of the proposed concepts in terms of the DFM objectives. The selected best fit concept is translated to design in the last stage, when the chosen concept is communicated to the development team. The detailed design is carried out in parallel to marketing and product development.

Targeted FA is shown to enable generation of innovative solutions, while improving manufacturability. The present research stands as a starting point in the development of product design methodologies that use RP and RT applications for manufacturing physical products.
A Manufacturing System for Advanced Multi-Process Manufacturing Based on Step-NC
Authors: Rauch Matthieu , Hascoet Jean-Yves
Published: August 2013

Companies have to propose flexibility and interoperability in addition to robustness and efficiency to meet today demand of high customized products. The rise of high level object-oriented data models such as ISO 14649 — know as STEP-NC — enables manufacturing engineers to meet these requirements. In parallel, new manufacturing processes are now available. Theses processes, such as incremental sheet forming or cladding, are mature enough to be used in the industry. In addition to that, they are CNC controlled. They can be totally integrated into manufacturing data chains. It is consequently possible to use several processes on the same part and develop multi-process manufacturing approaches. Their success lies mainly upon the ability to select the best process with the best parameterization. The use of intelligent manufacturing systems is of great help to achieve this goal.

The objective of this paper is to propose an intelligent manufacturing environment for multi-process manufacturing. Simulation and optimization approaches, advanced CNC programming methods are implemented in a coordinate way. Current CAD/CAM/CNC data chains limitations are overtaken by using STEP-NC. Finally, a practical implementation of such system is introduced. This experimental platform enables multi-process manufacturing with the industrial manufacturing equipment of the laboratory.
Tri-Dimensional Optical Inspection Based on Flexible Image Guide: First Step Toward 3D Industrial Endoscopy
Authors: Dupont Erwan , Lamarque Frédéric , Prelle Christine , Redarce Tanneguy
Published: August 2013

3D optical endoscopy is now a major challenge to allow the high resolution inspection of industrial equipments. The proposed instrument is based on a flexible image guide (70 000 fibres) and a Digital Micro mirror Device (DMD, 1024 × 768 “on-off” micro mirrors). The optical design is as follows: the light emitted by a 532 nm laser diode is dynamically structured by the DMD chip as a fringes pattern which is phase-shifted due to the active control of the DMD chip and projected onto an object on a circular field of 6 mm in diameter. Due to a telecentric and binocular arrangement that creates a stereoscopic angle, it is possible to get a depth of field of 2 mm along the optical axis without keystone distortions and few disturbances created by defocus and coma aberrations. Then, images are captured by a 1024 × 768 digital camera (not yet moved away by fibres) at 15 fps and directly used in the reconstruction algorithm to access the tri-dimensional shape of the unpainted object. The results are compared to incoherent white light results obtained with white painted mechanical objects. The lateral resolution is 31.3 μm and the RMS axial resolution is 10 μm for the laser-based design after speckle attenuation.
Design of a Hybrid Acoustic Device Based on Proof-Mass Actuators
Authors: Braghin Francesco , Castelli-Dezza Francesco , Cinquemani Simone , Resta Ferruccio
Published: August 2013

The paper deals with the design of a device for sound reproduction to be fixed to a supporting surface. The device is made up of two different types of acoustic actuators based on different technologies that allow good sound reproduction in the range of frequencies from 20Hz to 20kHz. The generation of sound at high frequencies is demanded to a magnetostrictive actuator, while a more traditional magnetodynamics actuator is used to generate sound at low frequencies. The coupling between these two actuators leads to a device having small overall dimensions and high performance.
Rheological Modelling of Carbon Black Aggregate Suspensions
Authors: Mahaud Morgane , Ma Anson , Chinesta Francisco , Leygue Adrien , Cueto Elias
Published: August 2013

Carbon Black (CB) and carbon nanotubes (CNTs) are both nano-scale forms of graphitic carbon (CB presents itself as nano-spheres of carbon). Both have excellent electrical, thermal and mechanical properties, what why they are often used in composite fabrication.