The evolution, morphology and development of fern leaves

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Alejandra eVasco

2013-09-01

Full Text Available Leaves are lateral determinate structures formed in a predictable sequence (phyllotaxy on the flanks of an indeterminate shoot apical meristem. The origin and evolution of leaves in vascular plants has been widely debated. Being the main conspicuous organ of nearl all vascular plants and often easy to recognize as such, it seems surprising that leaves have had multiple origins. For decades, morphologists, anatomists, paleobotanists, and systematists have contributed data to this debate. More recently, molecular genetic studies have provided insight into leaf evolution and development mainly within angiosperms and, to a lesser extent, lycophytes. There has been recent interest in extending leaf evolutionary developmental studies to other species and lineages, particularly in lycophytes and ferns. Therefore, a review of fern leaf morphology, evolution and development is timely. Here we discuss the theories of leaf evolution in ferns, morphology and diversity of fern leaves, and experimental results of fern leaf development. We summarize what is known about the molecular genetics of fern leaf development and what future studies might tell us about the evolution of fern leaf development.

Chloroplast Genome Evolution in Early Diverged Leptosporangiate Ferns

OpenAIRE

Kim, Hyoung Tae; Chung, Myong Gi; Kim, Ki-Joong

2014-01-01

In this study, the chloroplast (cp) genome sequences from three early diverged leptosporangiate ferns were completed and analyzed in order to understand the evolution of the genome of the fern lineages. The complete cp genome sequence of Osmunda cinnamomea (Osmundales) was 142,812 base pairs (bp). The cp genome structure was similar to that of eusporangiate ferns. The gene/intron losses that frequently occurred in the cp genome of leptosporangiate ferns were not found in the cp genome of O. c...

A molecular phylogeny of scaly tree ferns (Cyatheaceae).

Science.gov (United States)

Korall, Petra; Conant, David S; Metzgar, Jordan S; Schneider, Harald; Pryer, Kathleen M

2007-05-01

Tree ferns recently were identified as the closest sister group to the hyperdiverse clade of ferns, the polypods. Although most of the 600 species of tree ferns are arborescent, the group encompasses a wide range of morphological variability, from diminutive members to the giant scaly tree ferns, Cyatheaceae. This well-known family comprises most of the tree fern diversity (∼500 species) and is widespread in tropical, subtropical, and south temperate regions of the world. Here we investigate the phylogenetic relationships of scaly tree ferns based on DNA sequence data from five plastid regions (rbcL, rbcL-accD IGS, rbcL-atpB IGS, trnG-trnR, and trnL-trnF). A basal dichotomy resolves Sphaeropteris as sister to all other taxa and scale features support these two clades: Sphaeropteris has conform scales, whereas all other taxa have marginate scales. The marginate-scaled clade consists of a basal trichotomy, with the three groups here termed (1) Cyathea (including Cnemidaria, Hymenophyllopsis, Trichipteris), (2) Alsophila sensu stricto, and (3) Gymnosphaera (previously recognized as a section within Alsophila) + A. capensis. Scaly tree ferns display a wide range of indusial structures, and although indusium shape is homoplastic it does contain useful phylogenetic information that supports some of the larger clades recognised.

Diagnosis of climbing related overuse injuries

International Nuclear Information System (INIS)

Klauser, A.; Frauscher, F.; Helweg, G.; Nedden, D. zur; Hochholzer, T.; Kramer, J.

2002-01-01

Sport climbing shows an enormous increase in participation, evolving to more popularity, including even school sport activity on high standards. Therefore the number of climbing related injuries is increasing and becomes a more frequently encountered medical problem. Typical climbing associated injuries involve predominantly the upper limb. Overuse injuries are the most common climbing related injuries.The clinical examination is the first line investigation, which is often limited especially in the acute phase. However, an exact diagnosis is desireable for therapeutic management. Imaging modalities have shown to be capable for detection of climbing related injuries. An overview about the current use of x-ray, ultrasound and magnetic resonance imaging in different climbing related overuse injuries is presented. (orig.) [de

Two new fern chloroplasts and decelerated evolution linked to the long generation time in tree ferns.

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Zhong, Bojian; Fong, Richard; Collins, Lesley J; McLenachan, Patricia A; Penny, David

2014-04-30

We report the chloroplast genomes of a tree fern (Dicksonia squarrosa) and a "fern ally" (Tmesipteris elongata), and show that the phylogeny of early land plants is basically as expected, and the estimates of divergence time are largely unaffected after removing the fastest evolving sites. The tree fern shows the major reduction in the rate of evolution, and there has been a major slowdown in the rate of mutation in both families of tree ferns. We suggest that this is related to a generation time effect; if there is a long time period between generations, then this is probably incompatible with a high mutation rate because otherwise nearly every propagule would probably have several lethal mutations. This effect will be especially strong in organisms that have large numbers of cell divisions between generations. This shows the necessity of going beyond phylogeny and integrating its study with other properties of organisms. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Large-scale phylogenomic analysis resolves a backbone phylogeny in ferns

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Shen, Hui; Jin, Dongmei; Shu, Jiang-Ping; Zhou, Xi-Le; Lei, Ming; Wei, Ran; Shang, Hui; Wei, Hong-Jin; Zhang, Rui; Liu, Li; Gu, Yu-Feng; Zhang, Xian-Chun; Yan, Yue-Hong

2018-01-01

Abstract Background Ferns, originated about 360 million years ago, are the sister group of seed plants. Despite the remarkable progress in our understanding of fern phylogeny, with conflicting molecular evidence and different morphological interpretations, relationships among major fern lineages remain controversial. Results With the aim to obtain a robust fern phylogeny, we carried out a large-scale phylogenomic analysis using high-quality transcriptome sequencing data, which covered 69 fern species from 38 families and 11 orders. Both coalescent-based and concatenation-based methods were applied to both nucleotide and amino acid sequences in species tree estimation. The resulting topologies are largely congruent with each other, except for the placement of Angiopteris fokiensis, Cheiropleuria bicuspis, Diplaziopsis brunoniana, Matteuccia struthiopteris, Elaphoglossum mcclurei, and Tectaria subpedata. Conclusions Our result confirmed that Equisetales is sister to the rest of ferns, and Dennstaedtiaceae is sister to eupolypods. Moreover, our result strongly supported some relationships different from the current view of fern phylogeny, including that Marattiaceae may be sister to the monophyletic clade of Psilotaceae and Ophioglossaceae; that Gleicheniaceae and Hymenophyllaceae form a monophyletic clade sister to Dipteridaceae; and that Aspleniaceae is sister to the rest of the groups in eupolypods II. These results were interpreted with morphological traits, especially sporangia characters, and a new evolutionary route of sporangial annulus in ferns was suggested. This backbone phylogeny in ferns sets a foundation for further studies in biology and evolution in ferns, and therefore in plants. PMID:29186447

Large-scale phylogenomic analysis resolves a backbone phylogeny in ferns.

Science.gov (United States)

Shen, Hui; Jin, Dongmei; Shu, Jiang-Ping; Zhou, Xi-Le; Lei, Ming; Wei, Ran; Shang, Hui; Wei, Hong-Jin; Zhang, Rui; Liu, Li; Gu, Yu-Feng; Zhang, Xian-Chun; Yan, Yue-Hong

2018-02-01

Ferns, originated about 360 million years ago, are the sister group of seed plants. Despite the remarkable progress in our understanding of fern phylogeny, with conflicting molecular evidence and different morphological interpretations, relationships among major fern lineages remain controversial. With the aim to obtain a robust fern phylogeny, we carried out a large-scale phylogenomic analysis using high-quality transcriptome sequencing data, which covered 69 fern species from 38 families and 11 orders. Both coalescent-based and concatenation-based methods were applied to both nucleotide and amino acid sequences in species tree estimation. The resulting topologies are largely congruent with each other, except for the placement of Angiopteris fokiensis, Cheiropleuria bicuspis, Diplaziopsis brunoniana, Matteuccia struthiopteris, Elaphoglossum mcclurei, and Tectaria subpedata. Our result confirmed that Equisetales is sister to the rest of ferns, and Dennstaedtiaceae is sister to eupolypods. Moreover, our result strongly supported some relationships different from the current view of fern phylogeny, including that Marattiaceae may be sister to the monophyletic clade of Psilotaceae and Ophioglossaceae; that Gleicheniaceae and Hymenophyllaceae form a monophyletic clade sister to Dipteridaceae; and that Aspleniaceae is sister to the rest of the groups in eupolypods II. These results were interpreted with morphological traits, especially sporangia characters, and a new evolutionary route of sporangial annulus in ferns was suggested. This backbone phylogeny in ferns sets a foundation for further studies in biology and evolution in ferns, and therefore in plants. © The Authors 2017. Published by Oxford University Press.

How early ferns became trees.

Science.gov (United States)

Galtier, J; Hueber, F M

2001-09-22

A new anatomically preserved fern, discovered from the basalmost Carboniferous of Australia, shows a unique combination of very primitive anatomical characters (solid centrarch cauline protostele) with the elaboration of an original model of the arborescent habit. This plant possessed a false trunk composed of a repetitive branching system of very small stems, which established it as the oldest tree-fern known to date. The potential of this primitive zygopterid fern to produce such an unusual growth form-without real equivalent among living plants-is related to the possession of two kinds of roots that have complementary functional roles: (i) large roots produced by stems with immediate positive geotropism, strongly adapted to mechanical support and water uptake from the soil; and (ii) small roots borne either on large roots or on petiole bases for absorbing humidity inside the false trunk.

Towards resolving the complete fern tree of life.

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Lehtonen, Samuli

2011-01-01

In the past two decades, molecular systematic studies have revolutionized our understanding of the evolutionary history of ferns. The availability of large molecular data sets together with efficient computer algorithms, now enables us to reconstruct evolutionary histories with previously unseen completeness. Here, the most comprehensive fern phylogeny to date, representing over one-fifth of the extant global fern diversity, is inferred based on four plastid genes. Parsimony and maximum-likelihood analyses provided a mostly congruent results and in general supported the prevailing view on the higher-level fern systematics. At a deep phylogenetic level, the position of horsetails depended on the optimality criteria chosen, with horsetails positioned as the sister group either of Marattiopsida-Polypodiopsida clade or of the Polypodiopsida. The analyses demonstrate the power of using a 'supermatrix' approach to resolve large-scale phylogenies and reveal questionable taxonomies. These results provide a valuable background for future research on fern systematics, ecology, biogeography and other evolutionary studies.

Towards resolving the complete fern tree of life.

Directory of Open Access Journals (Sweden)

Samuli Lehtonen

Full Text Available In the past two decades, molecular systematic studies have revolutionized our understanding of the evolutionary history of ferns. The availability of large molecular data sets together with efficient computer algorithms, now enables us to reconstruct evolutionary histories with previously unseen completeness. Here, the most comprehensive fern phylogeny to date, representing over one-fifth of the extant global fern diversity, is inferred based on four plastid genes. Parsimony and maximum-likelihood analyses provided a mostly congruent results and in general supported the prevailing view on the higher-level fern systematics. At a deep phylogenetic level, the position of horsetails depended on the optimality criteria chosen, with horsetails positioned as the sister group either of Marattiopsida-Polypodiopsida clade or of the Polypodiopsida. The analyses demonstrate the power of using a 'supermatrix' approach to resolve large-scale phylogenies and reveal questionable taxonomies. These results provide a valuable background for future research on fern systematics, ecology, biogeography and other evolutionary studies.

A Star-Wheel Stair-Climbing Wheelchair

Institute of Scientific and Technical Information of China (English)

ZHANG Li; WU Bo; JIN Ai-min; JIANG Shi-hong; ZHENG Yu-fei; ZHANG Shuai

2014-01-01

In order to achieve a wheelchair climb stairs function, this paper designs a star-wheel stair-climbing mechanism. Through the effect of the lock coupling, the star-wheel stair-climbing mechanism is formed to be fixed axis gear train or planetary gear train achieving flat-walking and stair-climbing functions. Crossing obstacle analysis obtains the maximum height and minimum width of obstacle which the wheelchair can cross. Stress-strain analysis in Solidworks simulation is performed to verify material strength.

Organelle Genome Inheritance in Deparia Ferns (Athyriaceae, Aspleniineae, Polypodiales

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Li-Yaung Kuo

2018-04-01

Full Text Available Organelle genomes of land plants are predominately inherited maternally but in some cases can also be transmitted paternally or biparentally. Compared to seed plants (>83% genera of angiosperms and >12% genera of gymnosperms, plastid genome (plastome inheritance has only been investigated in fewer than 2% of fern genera, and mitochondrial genome (mitogenome from only one fern genus. We developed a new and efficient method to examine plastome and mitogenome inheritance in a fern species—Deparia lancea (Athyriaceae, Aspleniineae, Polypodiales, and found that plastid and mitochondrial DNAs were transmitted from only the maternal parentage to a next generation. To further examine whether both organelle genomes have the same manner of inheritance in other Deparia ferns, we sequenced both plastid and mitochondrial DNA regions of inter-species hybrids, and performed phylogenetic analyses to identify the origins of organellar DNA. Evidence from our experiments and phylogenetic analyses support that both organelle genomes in Deparia are uniparentally and maternally inherited. Most importantly, our study provides the first report of mitogenome inheritance in eupolypod ferns, and the second one among all ferns.

Tree Climbing Robot Design, Kinematics and Motion Planning

CERN Document Server

Lam, Tin Lun

2012-01-01

Climbing robot is a challenging research topic that has gained much attention from researchers. Most of the robots reported in the literature are designed to climb on manmade structures, but seldom robots are designed for climbing natural environment such as trees. Trees and manmade structures are very different in nature. It brings different aspects of technical challenges to the robot design. In this book, you can find a collection of the cutting edge technologies in the field of tree-climbing robot and the ways that animals climb. It provides a valuable reference for robot designers to select appropriate climbing methods in designing tree-climbing robots for specific purposes. Based on the study, a novel bio-inspired tree-climbing robot with several breakthrough performances has been developed and presents in this book. It is capable of performing various actions that is impossible in the state-of-the-art tree-climbing robots, such as moving between trunk and branches. This book also proposes several appro...

Bouldering: an alternative strategy to long-vertical climbing in root-climbing hortensias.

Science.gov (United States)

Granados Mendoza, Carolina; Isnard, Sandrine; Charles-Dominique, Tristan; Van den Bulcke, Jan; Rowe, Nick P; Van Acker, Joris; Goetghebeur, Paul; Samain, Marie-Stéphanie

2014-10-06

In the Neotropics, the genus Hydrangea of the popular ornamental hortensia family is represented by climbing species that strongly cling to their support surface by means of adhesive roots closely positioned along specialized anchoring stems. These root-climbing hortensia species belong to the nearly exclusive American Hydrangea section Cornidia and generally are long lianescent climbers that mostly flower and fructify high in the host tree canopy. The Mexican species Hydrangea seemannii, however, encompasses not only long lianescent climbers of large vertical rock walls and coniferous trees, but also short 'shrub-like' climbers on small rounded boulders. To investigate growth form plasticity in root-climbing hortensia species, we tested the hypothesis that support variability (e.g. differences in size and shape) promotes plastic responses observable at the mechanical, structural and anatomical level. Stem bending properties, architectural axis categorization, tissue organization and wood density were compared between boulder and long-vertical tree-climbers of H. seemannii. For comparison, the mechanical patterns of a closely related, strictly long-vertical tree-climbing species were investigated. Hydrangea seemannii has fine-tuned morphological, mechanical and anatomical responses to support variability suggesting the presence of two alternative root-climbing strategies that are optimized for their particular environmental conditions. Our results suggest that variation of some stem anatomical traits provides a buffering effect that regulates the mechanical and hydraulic demands of two distinct plant architectures. The adaptive value of observed plastic responses and the importance of considering growth form plasticity in evolutionary and conservation studies are discussed. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Lifting as You Climb

Science.gov (United States)

Sullivan, Debra R.

2009-01-01

This article addresses leadership themes and answers leadership questions presented to "Exchange" by the Panel members who attended the "Exchange" Panel of 300 Reception in Dallas, Texas, last November. There is an old proverb that encourages people to lift as they climb: "While you climb a mountain, you must not forget others along the way." With…

Indoor rock climbing: who gets injured?

Science.gov (United States)

Wright, D M; Royle, T J; Marshall, T

2001-06-01

To determine the frequency of overuse injury in indoor climbers, the common sites of such injury, and the factors that influence the probability that a climber will have sustained an overuse injury while climbing indoors. A semisupervised questionnaire was used to survey overuse injury in 295 spectators and competitors at the Entre-Prises World Climbing Championships held in Birmingham 3-5 December 1999. Statistical analysis included simple cross tabulations, calculation of odds ratios, and multiple logistic regression to explore the effect of several factors simultaneously. Some 44% of respondents had sustained an overuse injury, 19% at more than one site. The most common site of injury was the fingers. Univariate analysis showed that the probability of having sustained a climbing injury is higher in men (p = 0.009), those who have climbed for more than 10 years (p = 0.006), those who climb harder routes (p<0.0005), and those who boulder or lead more than they top rope (p<0.0005). The relation between lead grade and climbing injury is linear. Multivariate analysis removed the effect of sex as an independent predictor. Many climbers sustain overuse injury. The most at risk are those with the most ability and dedication to climbing. Climbers should be aware of the risk factors that influence injury and be able to spot the signs and symptoms of injury once they occur.

Allelopathic assessment of selected common weeds in Malaysia

Science.gov (United States)

Nurul Ain, M. B.; Nornasuha, Y.; Ismail, B. S.

2016-11-01

A laboratory study was conducted to evaluate the allelopathic potential of eight common weed species in Malaysia, namely, Ageratum conyzoides, Tridax procumbens, Cyperus iria, Fimbristylis miliacea, Eleusine indica, Imperata cylindrica, Lygodium flexuosum and Nephrolepis biserrata of different morphological characteristics (broadleaves, sedges, grasses and ferns). The allelopathic study of these weeds was carried out by testing the leaf litter leachate through the Sandwich method and the volatile compounds of these weeds through the Dish pack method with three replicates for each donor species. The results obtained from both methods were statistically analyzed and the means had converted to percentage growth inhibition to determine the inhibition pattern on the radicle and hypocotyl growth of lettuce seedlings. Among the eight weed species tested, Ageratum conyzoides showed the strongest growth inhibition on lettuce radicle elongation (86%) in the sandwich bioassay compared to the control, followed by Tridax procumbens (71%), which both species being broadleaves weeds. In the dish pack bioassay Lygodium flexuosum (fern) demonstrated maximum inhibition on the growth the radicle and hypocotyl for each different distance from the source well. On the other hand, two weed species exhibited enhanced on the growth radicle and hypocotyl when compared to that of the control in dish pack bioassay. Nephrolepis biserrata and Fimbristylis miliacea were the species that showed the highest growth stimulatory effect. The results presented can be utilized as benchmark information for further research on the elucidation of leachates and volatile chemicals involved in allelopathy in nature. The information can also be helpful in the development of new bioactive chemicals from natural products in weed control strategies.

Kinematic and Dynamic Analysis of a Cable-Climbing Robot

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Xu Fengyu

2015-07-01

Full Text Available To inspect broken cables or a cracked protective layer on cable-stayed bridges, a cable-climbing robot has been proposed and designed. In this paper, the complex 3D obstacles that may be encountered on cables are theoretically described, in order to investigate the obstacle-climbing capability of the cable-climbing robot. A climbing model is then proposed and used to design the robot. In the climbing model, two driven wheels are independently supported with a spring. Kinematics and dynamics models are further derived for the obstacle-climbing capabilities of the driving and driven wheels of the robot. In addition, the robot's obstacle-climbing tracks and its obstacle-climbing performance are simulated. Payload and obstacle-climbing experiments were conducted on the climbing robot in the laboratory. Based on the results of the simulation and the experiments, we obtained the variation of the driving torque in obstacle climbing. The contribution of this paper is intended to provide a basis for the precise motion control of the robot.

Evolutionary novelty versus exaptation: oral kinematics in feeding versus climbing in the waterfall-climbing Hawaiian Goby Sicyopterus stimpsoni.

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Joshua A Cullen

Full Text Available Species exposed to extreme environments often exhibit distinctive traits that help meet the demands of such habitats. Such traits could evolve independently, but under intense selective pressures of extreme environments some existing structures or behaviors might be coopted to meet specialized demands, evolving via the process of exaptation. We evaluated the potential for exaptation to have operated in the evolution of novel behaviors of the waterfall-climbing gobiid fish genus Sicyopterus. These fish use an "inching" behavior to climb waterfalls, in which an oral sucker is cyclically protruded and attached to the climbing surface. They also exhibit a distinctive feeding behavior, in which the premaxilla is cyclically protruded to scrape diatoms from the substrate. Given the similarity of these patterns, we hypothesized that one might have been coopted from the other. To evaluate this, we filmed climbing and feeding in Sicyopterus stimpsoni from Hawai'i, and measured oral kinematics for two comparisons. First, we compared feeding kinematics of S. stimpsoni with those for two suction feeding gobiids (Awaous guamensis and Lentipes concolor, assessing what novel jaw movements were required for algal grazing. Second, we quantified the similarity of oral kinematics between feeding and climbing in S. stimpsoni, evaluating the potential for either to represent an exaptation from the other. Premaxillary movements showed the greatest differences between scraping and suction feeding taxa. Between feeding and climbing, overall profiles of oral kinematics matched closely for most variables in S. stimpsoni, with only a few showing significant differences in maximum values. Although current data cannot resolve whether oral movements for climbing were coopted from feeding, or feeding movements coopted from climbing, similarities between feeding and climbing kinematics in S. stimpsoni are consistent with evidence of exaptation, with modifications, between these

Evolutionary novelty versus exaptation: oral kinematics in feeding versus climbing in the waterfall-climbing Hawaiian Goby Sicyopterus stimpsoni.

Science.gov (United States)

Cullen, Joshua A; Maie, Takashi; Schoenfuss, Heiko L; Blob, Richard W

2013-01-01

Species exposed to extreme environments often exhibit distinctive traits that help meet the demands of such habitats. Such traits could evolve independently, but under intense selective pressures of extreme environments some existing structures or behaviors might be coopted to meet specialized demands, evolving via the process of exaptation. We evaluated the potential for exaptation to have operated in the evolution of novel behaviors of the waterfall-climbing gobiid fish genus Sicyopterus. These fish use an "inching" behavior to climb waterfalls, in which an oral sucker is cyclically protruded and attached to the climbing surface. They also exhibit a distinctive feeding behavior, in which the premaxilla is cyclically protruded to scrape diatoms from the substrate. Given the similarity of these patterns, we hypothesized that one might have been coopted from the other. To evaluate this, we filmed climbing and feeding in Sicyopterus stimpsoni from Hawai'i, and measured oral kinematics for two comparisons. First, we compared feeding kinematics of S. stimpsoni with those for two suction feeding gobiids (Awaous guamensis and Lentipes concolor), assessing what novel jaw movements were required for algal grazing. Second, we quantified the similarity of oral kinematics between feeding and climbing in S. stimpsoni, evaluating the potential for either to represent an exaptation from the other. Premaxillary movements showed the greatest differences between scraping and suction feeding taxa. Between feeding and climbing, overall profiles of oral kinematics matched closely for most variables in S. stimpsoni, with only a few showing significant differences in maximum values. Although current data cannot resolve whether oral movements for climbing were coopted from feeding, or feeding movements coopted from climbing, similarities between feeding and climbing kinematics in S. stimpsoni are consistent with evidence of exaptation, with modifications, between these behaviors. Such

THE ANTIMICROBIAL ACTIVITY OF SOME EXTRACTS OF FERN GAMETOPHYTES

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Ionica Deliu

2013-12-01

Full Text Available The nature freely offers us many resources for health and beauty. The ferns and their therapeutic properties are less exploit in Romania, except Lycopodium clavatum and Equisetum arvense. Some of the fern properties were demonstrated, like antioxidant, antimicrobial, antiviral, antihelmintic properties. Plants are reasonable alternative to synthetic drugs, avoid the side effect and high cost of synthetic drugs production. Also, the drug resistance bacteria can be controlled using plant derived remedies. In this study the antimicrobial effect of methanolic and ethanolic extracts from three fern species were tested. The extracts were gained from gametophytic stage of ferns obtained in vitro. The most obvious effect was observed for Asplenium trichomanes-ramosum extract. The total polyphenols and flavonoids content were established, too.

Spectroscopic Analysis of Arsenic Uptake in Pteris Ferns

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Terrence Slonecker

2009-09-01

Full Text Available Two arsenic-accumulating Pteris ferns (Pteris cretica mayii and Pteris multifida, along with a non-accumulating control fern (Nephrolepis exaltata were grown in greenhouse conditions in clean sand spiked with 0, 20, 50, 100 and 200 ppm sodium arsenate. Spectral data were collected for each of five replicates prior to harvest at 4-week intervals. Fern samples were analyzed for total metals content and Partial Least Squares and Stepwise Linear Regression techniques were used to develop models from the spectral data. Results showed that Pteris cretica mayii and Pteris multifida are confirmed hyperaccumulators of inorganic arsenic and that reasonably accurate predictive models of arsenic concentration can be developed from the first derivative of spectral reflectance of the hyperaccumulating Pteris ferns. Both the arsenic uptake and spectral results indicate that there is some species-specific variability but the results compare favorably with previously published data and additional research is recommended.

Effects of Sport Climbing on Multiple Sclerosis

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Julia Steimer

2017-12-01

Full Text Available Multiple sclerosis (MS is an autoimmune and neurodegenerative disease of the central nervous system (CNS with different types of disease courses (relapsing-remitting, secondary-progressive, primary progressive that leads to physical as well as mental disability. The symptoms comprise paresis or/and paralysis, ataxia, bladder dysfunction, visual problems as well as effects on cognition. There is limited data regarding the possible effects of sport climbing respectively therapeutic climbing on patients with MS. Sport climbing offers many potentially beneficial effects for patients with MS since there are effects on coordination, muscular strength, and cognition to name the most relevant ones. Also, disease models in rodents point toward such positive outcomes of climbing. Therefore, we assessed the currently available research literature on general effects of physical exercise, impact of climbing on body and mind and therapeutic climbing for prevention or therapy for the treatment of MS. The sparse published controlled trials that investigated this sport activity on different groups of patients with neurological or geriatric diseases grossly differ in study design and outcome parameters. Nevertheless, it appears that climbing offers the opportunity to improve some of the symptoms of patients with MS and can contribute to an enhanced quality of life.

Screening for ptaquiloside in ferns

DEFF Research Database (Denmark)

Rasmussen, Lars Holm; Pedersen, Henrik Ærenlund

2017-01-01

. Objective: To set-up a methodology for large-scale qualitative studies on the distribution of PTA in ferns using already available herbarium specimens as source. Methodology: PTA and the main degradation product pterosin B (PtB) were quantified in aqueous frond extracts by HPLC-DAD. PTA was quantified after...... of the analyte was obtained. Preservation of fronds in a plant press increase formation of PtB. Hence, the method is only suitable for qualitative studies. Presence of PTA and PtB were found in samples up to 50 years old. Among 21 ferns tested, the compounds were only found in Pteridium aquilinum. Conclusion...

Morphology, Physiology, and Anatomy of Penny Fern (Drymoglossum phyloselloidesand Its Effect on Cocoa

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Fitria Yuliasmara

2013-08-01

Full Text Available This study aims to determine the anatomy, physiology and morphology of penny fern (Drimoglosum phylloseloides and its effect on cocoa. Morphological observation of penny fern used microscope to observe the roots, stems, leaves and spores. Physiology of penny fern was observed based on number of stomata and stomatal conductance using stomata printing method, while the amount of chlorophyll based on spectrophotometric method and rate of transpiration used cobalt chloride paper. Penny fern anatomy on cross-sectional and longitudinal in roots, stems and leaves. Penny fern growth was observed based the length of tendrils once a week during rainy and dry season. While the effect of penny fern invasion was observed based on variable leaf area with gravimetric method, the cross-section of attacked cacao branch using microtom and microscope and chlorophyll content by chlorophyll meter. Results showed that penny fern is a epiphytic weed which was crassulaceae acid metabolism plants that have the ability to absorb carbon dioxide at night and carry out photosynthesis during the day with closed stomata. Penny ferns reproduce using spores. The growth rate of penny fern 2.18 cm/week during the dry season and while in rainy season 3.89 cm/week. Penny fern leaf contains 0.0212 mg/g chlorophyll. Penny fern stomata density was 18.33/mm 2 with a width of opening stomata at night 26.3 µm which caused a veryslow rate of transpiration of 0.69 mm 2 /seconds. The existence penny fern on cocoa decreased leaf area and chlorophyll content decreased crop productivity which was indicated by decreasing in number of flowers, number of small, medium fruit, and large pods. However it had no effect on the number of leaves on one side flush cocoa. Key words: Drimoglosum phylloseloides, weeds, decrease productivity, Theobroma cacao

Random clustering ferns for multimodal object recognition

OpenAIRE

Villamizar Vergel, Michael Alejandro; Garrell Zulueta, Anais; Sanfeliu Cortés, Alberto; Moreno-Noguer, Francesc

2017-01-01

The final publication is available at link.springer.com We propose an efficient and robust method for the recognition of objects exhibiting multiple intra-class modes, where each one is associated with a particular object appearance. The proposed method, called random clustering ferns, combines synergically a single and real-time classifier, based on the boosted assembling of extremely randomized trees (ferns), with an unsupervised and probabilistic approach in order to recognize efficient...

The evolutionary history of ferns inferred from 25 low-copy nuclear genes.

Science.gov (United States)

Rothfels, Carl J; Li, Fay-Wei; Sigel, Erin M; Huiet, Layne; Larsson, Anders; Burge, Dylan O; Ruhsam, Markus; Deyholos, Michael; Soltis, Douglas E; Stewart, C Neal; Shaw, Shane W; Pokorny, Lisa; Chen, Tao; dePamphilis, Claude; DeGironimo, Lisa; Chen, Li; Wei, Xiaofeng; Sun, Xiao; Korall, Petra; Stevenson, Dennis W; Graham, Sean W; Wong, Gane K-S; Pryer, Kathleen M

2015-07-01

• Understanding fern (monilophyte) phylogeny and its evolutionary timescale is critical for broad investigations of the evolution of land plants, and for providing the point of comparison necessary for studying the evolution of the fern sister group, seed plants. Molecular phylogenetic investigations have revolutionized our understanding of fern phylogeny, however, to date, these studies have relied almost exclusively on plastid data.• Here we take a curated phylogenomics approach to infer the first broad fern phylogeny from multiple nuclear loci, by combining broad taxon sampling (73 ferns and 12 outgroup species) with focused character sampling (25 loci comprising 35877 bp), along with rigorous alignment, orthology inference and model selection.• Our phylogeny corroborates some earlier inferences and provides novel insights; in particular, we find strong support for Equisetales as sister to the rest of ferns, Marattiales as sister to leptosporangiate ferns, and Dennstaedtiaceae as sister to the eupolypods. Our divergence-time analyses reveal that divergences among the extant fern orders all occurred prior to ∼200 MYA. Finally, our species-tree inferences are congruent with analyses of concatenated data, but generally with lower support. Those cases where species-tree support values are higher than expected involve relationships that have been supported by smaller plastid datasets, suggesting that deep coalescence may be reducing support from the concatenated nuclear data.• Our study demonstrates the utility of a curated phylogenomics approach to inferring fern phylogeny, and highlights the need to consider underlying data characteristics, along with data quantity, in phylogenetic studies. © 2015 Botanical Society of America, Inc.

Evolutionary and ecological perspectives of Late Paleozoic ferns. Part III. Anachoropterid ferns (including Anachoropteris, Tubicaulis, the Sermayaceae, Kaplanopteridaceae and Psalixochlaenaceae)

OpenAIRE

Galtier, Jean; Phillips, Tom L.

2014-01-01

The anachoropterid ferns, previously assigned to the family Anachoropteridaceae, are a group of anatomically preserved late Paleozoic filicalean ferns characterized by a C-shaped foliar xylem with abaxially recurved arms (inversicatenalean anatomy) and two main protoxylem strands. The variously curved to strongly inrolled foliar xylem certainly reflects different evolutionary trends within the morphogenus Anachoropteris. The occurrence of two groups of Tubicaulis is supported by differences i...

Tracked robot controllers for climbing obstacles autonomously

Science.gov (United States)

Vincent, Isabelle

2009-05-01

Research in mobile robot navigation has demonstrated some success in navigating flat indoor environments while avoiding obstacles. However, the challenge of analyzing complex environments to climb obstacles autonomously has had very little success due to the complexity of the task. Unmanned ground vehicles currently exhibit simple autonomous behaviours compared to the human ability to move in the world. This paper presents the control algorithms designed for a tracked mobile robot to autonomously climb obstacles by varying its tracks configuration. Two control algorithms are proposed to solve the autonomous locomotion problem for climbing obstacles. First, a reactive controller evaluates the appropriate geometric configuration based on terrain and vehicle geometric considerations. Then, a reinforcement learning algorithm finds alternative solutions when the reactive controller gets stuck while climbing an obstacle. The methodology combines reactivity to learning. The controllers have been demonstrated in box and stair climbing simulations. The experiments illustrate the effectiveness of the proposed approach for crossing obstacles.

Bio-inspired step-climbing in a hexapod robot

International Nuclear Information System (INIS)

Chou, Ya-Cheng; Yu, Wei-Shun; Huang, Ke-Jung; Lin, Pei-Chun

2012-01-01

Inspired by the observation that the cockroach changes from a tripod gait to a different gait for climbing high steps, we report on the design and implementation of a novel, fully autonomous step-climbing maneuver, which enables a RHex-style hexapod robot to reliably climb a step up to 230% higher than the length of its leg. Similar to the climbing strategy most used by cockroaches, the proposed maneuver is composed of two stages. The first stage is the ‘rearing stage,’ inclining the body so the front side of the body is raised and it is easier for the front legs to catch the top of the step, followed by the ‘rising stage,’ maneuvering the body's center of mass to the top of the step. Two infrared range sensors are installed on the front of the robot to detect the presence of the step and its orientation relative to the robot's heading, so that the robot can perform automatic gait transition, from walking to step-climbing, as well as correct its initial tilt approaching posture. An inclinometer is utilized to measure body inclination and to compute step height, thus enabling the robot to adjust its gait automatically, in real time, and to climb steps of different heights and depths successfully. The algorithm is applicable for the robot to climb various rectangular obstacles, including a narrow bar, a bar and a step (i.e. a bar of infinite width). The performance of the algorithm is evaluated experimentally, and the comparison of climbing strategies and climbing behaviors in biological and robotic systems is discussed. (paper)

The omnipresent water fern

NARCIS (Netherlands)

Nierop, K.G.J.; Speelman, E.N.; de Leeuw, J.W.; Reichart, G.J.

2011-01-01

Several studies have reported the presence of large amounts of lignin in ubiquitously occurring species of the freshwater fern Azolla. Molecular analysis using flash pyrolysis and thermally assisted hydrolysis and methylation shows, however, that neither the leaves nor the roots of Azolla contain

El historiador Fernández de Piedrahita

Directory of Open Access Journals (Sweden)

Carlos López Narváez

1964-10-01

Full Text Available Varón de Dios, las letras y la patria, Lucas Fernández de Piedrahita nació en Santafé de Bogotá, el 6 de marzo de 1624, de hidalgo linaje por su padre español, y de principesca sangre materna, como que su progenitora, doña Catalina Collantes, esposa de don Domingo Fernández de Soto y Piedrahita, era nieta de doña Francisca Coya de la realeza inca del Perú.

Variation of functional clonal traits along elevation in two fern species

International Nuclear Information System (INIS)

Song, Y.B.; Chen, L.Y.; Xiong, W.

2015-01-01

Phenotypical plasticity is generally considered among adaptive strategies by which plants can cope with environmental variation in space and time. Although much is known about plasticity in seed plants in terms of functional clonal traits while little is known about ferns. Variation of functional clonal traits of two ferns Dicranopteris dichotoma and Diplopterygium glaucum among plots differing in elevation in a subtropical evergreen broad-leaved forest in southern China was investigated. Along with elevation increasing the two fern species showed similar variation pattern of functional clonal traits: stable spacer length, increasing specific spacer length and decreasing spacer weight per ramet and specific spacer weight. The two ferns species had similar variation pattern of ramet performance traits but different variation pattern of ramet population properties. These results suggest an evolutionary trade-off between functions of foraging for and storing of resources in the two ferns, with a functional preference for the foraging in response to environmental change. (author)

Ultrasonic synthesis of fern-like ZnO nanoleaves and their enhanced photocatalytic activity

International Nuclear Information System (INIS)

Ma, Qing Lan; Xiong, Rui; Zhai, Bao-gai; Huang, Yuan Ming

2015-01-01

Graphical abstract: - Highlights: • Fern-like ZnO nanoleaves were synthesized by ultrasonicating Zn microcrystals in water. • A fern-like ZnO nanoleaf is a self-assembly of ZnO nanoplates along one ZnO nanorod. • Fern-like ZnO nanoleaves exhibit enhanced photocatalytic activity than ZnO nanocrystals. • The branched hierarchical structures are responsible for the enhanced photocatalytic activity. - Abstract: Two-dimensional fern-like ZnO nanoleaves were synthesized by ultrasonicating zinc microcrystals in water. The morphology, crystal structure, optical property and photocatalytic activity of the fern-like ZnO nanoleaves were characterized with scanning electron microscopy, X-ray diffraction, transmission electron microscopy, photoluminescence spectroscopy and ultraviolet–visible spectroscopy, respectively. It is found that one fern-like ZnO nanoleaf is composed of one ZnO nanorod as the central trunk and a number of ZnO nanoplates as the side branches in opposite pairs along the central ZnO nanorod. The central ZnO nanorod in the fern-like nanoleaves is about 1 μm long while the side-branching ZnO nanoplates are about 100 nm long and 20 nm wide. Further analysis has revealed that ZnO nanocrystals are the building blocks of the central ZnO nanorod and the side-branching ZnO nanoplates. Under identical conditions, fern-like ZnO nanoleaves exhibit higher photocatalytic activity in photodegrading methyl orange in aqueous solution than spherical ZnO nanocrystals. The first-order photocatalytic rate constant of the fern-like ZnO nanoleaves is about four times as large as that of the ZnO nanoparticles. The branched architecture of the hierarchical nanoleaves is suggested be responsible for the enhanced photocatalytic activity of the fern-like ZnO nanoleaves

The morphology of ferns

NARCIS (Netherlands)

Holttum, R.E.

1959-01-01

A fern plant consists of a stem, bearing leaves and roots. The leaves (or some of them) bear dehiscent sporangia, each sporangium containing unicellular spores, which are in most cases Wind-dispersed. A spore germinates to produce a small green plant called a prothallus. The Prothallus bears sexual

Activity of southeastern bats along sandstone cliffs used for rock climbing

Science.gov (United States)

Loeb, Susan C.; Jodice, Patrick G. R.

2018-01-01

Bats in the eastern U.S. are facing numerous threats and many species are in decline. Although several species of bats commonly roost in cliffs, little is known about use of cliffs for foraging and roosting. Because rock climbing is a rapidly growing sport and may cause disturbance to bats, our objectives were to examine use of cliff habitats by bats and to assess the effects of climbing on their activity. We used radio-telemetry to track small-footed bats (Myotis leibii) to day roosts, and Anabat SD2 detectors to compare bat activity between climbed and unclimbed areas of regularly climbed cliff faces, and between climbed and unclimbed cliffs. Four adult male small-footed bats were tracked to nine day roosts, all of which were in various types of crevices including five cliff face roosts (three on climbed and two on unclimbed faces). Bat activity was high along climbed cliffs and did not differ between climbed and unclimbed areas of climbed cliffs. In contrast, overall bat activity was significantly higher along climbed cliffs than unclimbed cliffs; species richness did not differ between climbed and unclimbed cliffs or areas. Lower activity along unclimbed cliffs may have been related to lower cliff heights and more clutter along these cliff faces. Due to limited access to unclimbed cliffs of comparable size to climbed cliffs, we could not thoroughly test the effects of climbing on bat foraging and roosting activity. However, the high overall use of climbed and unclimbed cliff faces for foraging and commuting that we observed suggests that cliffs may be important habitat for a number of bat species. Additional research on bats' use of cliff faces will improve our understanding of the factors that affect their use of this habitat including the impacts of climbing.

Distribution and dynamics of hayscented fern following stand harvest

Science.gov (United States)

Songlin Fei; Peter J. Gould; Melanie J. Kaeser; Kim C. Steiner

2008-01-01

The distribution and dynamics of hayscented fern were examined as part of a large-scale study of oak regeneration in Pennsylvania. The study included 69 stands covering 3,333 acres in two physiographic provinces. Hayscented fern was more widely distributed and occurred at higher densities in the Allegheny Plateau physiographic provinces versus the Ridge and Valley...

Fern of the future?

NARCIS (Netherlands)

Brinkhuis, H.; Bijl, P.K.

Held in the palm of a human hand, a single specimen of Azolla filiculoides looks downright inconsequential. Even with the scaly leaves of this miniature aquatic fern spread flat, it barely spans the distance between the creases that cleave the flesh. Its fibrous root tendrils dangle like a lock of

Asplenium bird’s nest ferns in rainforest canopies are climate-contingent refuges for frogs

Directory of Open Access Journals (Sweden)

Brett R. Scheffers

2014-12-01

Full Text Available Epiphytes are important for canopy dwelling organisms because they provide a cool and moist microhabitat in the relatively hot and dry canopy. Here we examine whether epiphytic Asplenium ferns act as important habitats for arboreal frogs. We conducted extensive fern and habitat surveys for frogs in the Philippines, and complimented these surveys with roaming day and night canopy surveys to identify the full extent of habitat use across the vertical strata. We artificially dried ferns of various sizes to identify relationships between water and temperature buffering. Ferns are the preferred diurnal microhabitat and breeding habitat for arboreal frogs. A strong positive relationship exists between fern size and frog usage and abundance. Our drying experiments show that large ferns buffer maximum temperatures and reduce variability in temperatures, and buffering is directly linked to their hydration. Frogs are likely using large ferns for their moist, cool, environments for breeding and daytime retreat, which supports the buffered microhabitat hypothesis—these plants promote species coexistence through habitat creation and amelioration of physical stress. However, drying experiments suggest that this buffering is contingent on regular rainfall. Altered rainfall regimes could lead to the unexpected loss of the functional capacity of these important fern habitats. Keywords: Climate change, Functionality, Microhabitat, Refuge, Ectotherm, Precipitation

New species of Malaysian ferns

NARCIS (Netherlands)

Holttum, R.E.

1962-01-01

The present paper includes descriptions of several new species of ferns found among recent collections from various parts of Malaysia; also two new combinations of names of species which are of interest on account of their taxonomic history.

Effectiveness and cost of two stair-climbing interventions-less is more.

Science.gov (United States)

Olander, Ellinor K; Eves, Frank F

2011-01-01

The current study compared two interventions for promotion of stair climbing in the workplace, an information-based intervention at a health information day and an environmental intervention (point-of-choice prompts), for their effectiveness in changing stair climbing and cost per employee. Interrupted time-series design. Four buildings on a university campus. Employees at a university in the United Kingdom. Two stair-climbing interventions were compared: (1) a stand providing information on stair climbing at a health information day and (2) point-of-choice prompts (posters). Observers recorded employees' gender and method of ascent (n = 4279). The cost of the two interventions was calculated. Logistic regression. There was no significant difference between baseline (47.9% stair climbing) and the Workplace Wellbeing Day (48.8% stair climbing), whereas the prompts increased stair climbing (52.6% stair climbing). The health information day and point-of-choice prompts cost $773.96 and $31.38, respectively. The stand at the health information day was more expensive than the point-of-choice prompts and was inferior in promoting stair climbing. It is likely that the stand was unable to encourage stair climbing because only 3.2% of targeted employees visited the stand. In contrast, the point-of-choice prompts were potentially visible to all employees using the buildings and hence better for disseminating the stair climbing message to the target audience.

Tear ferning test in healthy dogs.

Science.gov (United States)

Oriá, Arianne P; Raposo, Ana Claudia S; Araújo, Nayone L L C; Lima, Felipe B; Masmali, Ali M

2017-11-07

To evaluate and compare three tear sampling methods using two grading scales for administering the tear ferning test (TFT) to healthy dogs. In total, 90 dogs (180 eyes) were subjected to tear sampling using millimetered strips, reused after the Schirmer tear test (STT) (Schirmer group, SG). Then, the dogs were subdivided into three groups according to sampling approach: micropipette (MPG), microcapillary (MCG), and Schirmer sample 2 (S2G). The collected tears were dried on a clean microscope glass slide at room temperature and humidity. The ferning patterns were observed under a polarized light microscope and classified according to the Rolando and Masmali grading scales. Although all three methods were feasible, the STT was easier to perform in clinical settings. Type I and Grade 1 were the most commonly observed (64.17% and 61.7%, respectively) regardless of collection method. There was no significant difference between the STT median values and the TFT classifications. The TFT is appropriate for dogs and can be performed using the three suggested sampling methods, with a higher frequency of Type I and Grade 1. Thus, it is possible to use both grading scales in the classification of tear ferning in dogs. © 2017 American College of Veterinary Ophthalmologists.

Tree fern trunks facilitate seedling regeneration in a productive lowland temperate rain forest.

Science.gov (United States)

Gaxiola, Aurora; Burrows, Larry E; Coomes, David A

2008-03-01

Seedling regeneration on forest floors is often impaired by competition with established plants. In some lowland temperate rain forests, tree fern trunks provide safe sites on which tree species establish, and grow large enough to take root in the ground and persist. Here we explore the competitive and facilitative effects of two tree fern species, Cyathea smithii and Dicksonia squarrosa, on the epiphytic regeneration of tree species in nutrient-rich alluvial forests in New Zealand. The difficulties that seedlings have in establishing on vertical tree fern trunks were indicated by the following observations. First, seedling abundance was greatest on the oldest sections of tree fern trunks, near the base, suggesting that trunks gradually recruited more and more seedlings over time, but many sections of trunk were devoid of seedlings, indicating the difficulty of establishment on a vertical surface. Second, most seedlings were from small-seeded species, presumably because smaller seeds can easily lodge on tree fern trunks. Deer browsing damage was observed on 73% of epiphytic seedlings growing within 2 m of the ground, whereas few seedlings above that height were browsed. This suggests that tree ferns provide refugia from introduced deer, and may slow the decline in population size of deer-preferred species. We reasoned that tree ferns would compete with epiphytic seedlings for light, because below the tree fern canopy photosynthetically active radiation (PAR) was about 1% of above-canopy PAR. Frond removal almost tripled %PAR on the forest floor, leading to a significant increase in the height growth rate (HGR) of seedlings planted on the forest floor, but having no effects on the HGRs of epiphytic seedlings. Our study shows evidence of direct facilitative interactions by tree ferns during seedling establishment in plant communities associated with nutrient-rich soils.

CLIMB grammars: three projects using metagrammar engineering

NARCIS (Netherlands)

Fokkens, A.S.; Avgustinova, T.; Zhang, Yi

2012-01-01

This paper introduces the CLIMB (Comparative Libraries of Implementations with Matrix Basis) methodology and grammars. The basic idea behind CLIMB is to use code generation as a general methodology for grammar development in order to create a more systematic approach to grammar development. The

Biomechanical Analyses of Stair-climbing while Dual-tasking

Science.gov (United States)

Vallabhajosula, Srikant; Tan, Chi Wei; Mukherjee, Mukul; Davidson, Austin J.; Stergiou, Nicholas

2015-01-01

Stair-climbing while doing a concurrent task like talking or holding an object is a common activity of daily living which poses high risk for falls. While biomechanical analyses of overground walking during dual-tasking have been studied extensively, little is known on the biomechanics of stair-climbing while dual-tasking. We sought to determine the impact of performing a concurrent cognitive or motor task during stair-climbing. We hypothesized that a concurrent cognitive task will have a greater impact on stair climbing performance compared to a concurrent motor task and that this impact will be greater on a higher-level step. Ten healthy young adults performed 10 trials of stair-climbing each under four conditions: stair ascending only, stair ascending and performing subtraction of serial sevens from a three-digit number, stair ascending and carrying an empty opaque box and stair ascending, performing subtraction of serial sevens from a random three-digit number and carrying an empty opaque box. Kinematics (lower extremity joint angles and minimum toe clearance) and kinetics (ground reaction forces and joint moments and powers) data were collected. We found that a concurrent cognitive task impacted kinetics but not kinematics of stair-climbing. The effect of dual-tasking during stair ascent also seemed to vary based on the different phases of stair ascent stance and seem to have greater impact as one climbs higher. Overall, the results of the current study suggest that the association between the executive functioning and motor task (like gait) becomes stronger as the level of complexity of the motor task increases. PMID:25773590

The effectiveness of chocolate milk as a post-climbing recovery aid.

Science.gov (United States)

Potter, J; Fuller, B

2015-12-01

Recovery is essential to effective performance in climbing competitions which often involve repeated bouts, and sport climbing where climbers may work a route over a number of days prior to a complete ascent. This study employed a cross-over design to compare water with chocolate milk as recovery aids following an exhaustive bout of high intensity endurance climbing. Ten male climbers (age: 22±1 years; height: 178.5±7.9 cm; mass: 74.7±11.3 kg) climbed a Tredwall (Brewer Ledge M6) until volitional exhaustion. The participants consumed either water or chocolate milk 20 minutes after the climb and then again with their evening meal. The exercise protocol was repeated 24 hours after the original climb. The second condition was completed 7 days later. Workload indicators of heart rate, rate of perceived exertion (RPE), blood lactate and muscle soreness scores were recorded alongside climbing performance measures of duration and distance of the climb. A improved performance was found after the consumption of chocolate milk, with both a greater distance climbed (F(1,9)=11.704, P=0.008) and duration (F(1,9) =10.922, P=0.009), there were no differences in end of climb heart rate or RPE. Muscle soreness scores were lower three days after exercise following chocolate milk (t(8)=3.773, P=0.005). Chocolate milk as a recovery drink resulted in further sustained climbing, a decrease in muscle soreness, compared to water. It may be pertinent for climbers to consider its use as a recovery aid during repeated climbing bouts. Chocolate milk is a relatively unexplored recovery aid and warrants further attention.

Stasis and convergence characterize morphological evolution in eupolypod II ferns.

Science.gov (United States)

Sundue, Michael A; Rothfels, Carl J

2014-01-01

Patterns of morphological evolution at levels above family rank remain underexplored in the ferns. The present study seeks to address this gap through analysis of 79 morphological characters for 81 taxa, including representatives of all ten families of eupolypod II ferns. Recent molecular phylogenetic studies demonstrate that the evolution of the large eupolypod II clade (which includes nearly one-third of extant fern species) features unexpected patterns. The traditional 'athyrioid' ferns are scattered across the phylogeny despite their apparent morphological cohesiveness, and mixed among these seemingly conservative taxa are morphologically dissimilar groups that lack any obvious features uniting them with their relatives. Maximum-likelihood and maximum-parsimony character optimizations are used to determine characters that unite the seemingly disparate groups, and to test whether the polyphyly of the traditional athyrioid ferns is due to evolutionary stasis (symplesiomorphy) or convergent evolution. The major events in eupolypod II character evolution are reviewed, and character and character state concepts are reappraised, as a basis for further inquiries into fern morphology. Characters were scored from the literature, live plants and herbarium specimens, and optimized using maximum-parsimony and maximum-likelihood, onto a highly supported topology derived from maximum-likelihood and Bayesian analysis of molecular data. Phylogenetic signal of characters were tested for using randomization methods and fitdiscrete. The majority of character state changes within the eupolypod II phylogeny occur at the family level or above. Relative branch lengths for the morphological data resemble those from molecular data and fit an ancient rapid radiation model (long branches subtended by very short backbone internodes), with few characters uniting the morphologically disparate clades. The traditional athyrioid ferns were circumscribed based upon a combination of

Elevated uptake of Th and U by netted chain fern (Woodwardia areolata)

International Nuclear Information System (INIS)

Knox, A.S.; Kaplan, D.I.; Hinton, T.G.

2008-01-01

We assessed the ability of netted chain fern (Woodwardia areolata) to uptake U and Th from wetland soils on the U.S. Department of Energy's Savannah River Site in South Carolina. Netted chain fern had the highest Th and U concentrations of all plants collected from the wetland. Ferns grown in contaminated soil (329 mg x kg -1 Th, 44 mg x kg -1 U) in a greenhouse contained 6.4 mg x kg -1 Th and 5.3 mg x kg -1 U compared with 0.13 mg x kg -1 Th and 0.035 mg x kg -1 U in Bermuda grass (Cynodon dactylon). Netted chain fern has potential for the phytoremediation of soils contaminated with Th and U. (author)

PIXE study on absorption of arsenate and arsenite by arsenic hyperaccumulating fern (Pteris vittata)

International Nuclear Information System (INIS)

Yamazaki, H.; Ishii, K.; Matsuyama, S.

2008-01-01

Pytoremediation using an arsenic hyperaccumulator, Petris vittata L., has generated an increasing interest worldwide due to both environmentally sound and cost effectiveness. However the mechanism of arsenic accumulation by this fern is not clear at this time. This study examined the uptake of arsenate (As(V)) and arsenite (As(III)) by a hydroponic culture of Pteris vittata using both in-air submilli-PIXE for different parts of the fern and in-air micro-PIXE for the tissue cells. These PIXE analysis systems used 3 MeV proton beams from a 4.5-MV single-ended Dynamitron accelerator at Tohoku University, Japan. The fern took up both arsenate and arsenite from hydroponic solutions which were spiked with 50 mg of arsenic per litter. Final amount of arsenic accumulation in the fern is 1,500 mg per kg (wet weight) of the plant biomass in arsenite treatment and 1,100 mg per kg in arsenate treatment. Arsenic accumulation was not observed at the root parts of the ferns. The in-vivo mapping of elements by submilli-PIXE analyses on the fern laminas showed the arsenic accumulation in the edges of a pinna. The micro-PIXE analyses revealed arsenic maps homogeneously distributed in cells of the lamina, stem and rhizome of the fern. These results indicate that arsenic, both arsenate and arsenite in a contaminated medium are translocated quickly from roots to fronds of Pteris vittata, and distributes homogeneously into tissue cells of the fern laminas. (author)

Climbing plants: attachment adaptations and bioinspired innovations.

Science.gov (United States)

Burris, Jason N; Lenaghan, Scott C; Stewart, C Neal

2018-04-01

Climbing plants have unique adaptations to enable them to compete for sunlight, for which they invest minimal resources for vertical growth. Indeed, their stems bear relatively little weight, as they traverse their host substrates skyward. Climbers possess high tensile strength and flexibility, which allows them to utilize natural and manmade structures for support and growth. The climbing strategies of plants have intrigued scientists for centuries, yet our understanding about biochemical adaptations and their molecular undergirding is still in the early stages of research. Nonetheless, recent discoveries are promising, not only from a basic knowledge perspective, but also for bioinspired product development. Several adaptations, including nanoparticle and adhesive production will be reviewed, as well as practical translation of these adaptations to commercial applications. We will review the botanical literature on the modes of adaptation to climb, as well as specialized organs-and cellular innovations. Finally, recent molecular and biochemical data will be reviewed to assess the future needs and new directions for potential practical products that may be bioinspired by climbing plants.

Distribution and dynamics of the invasive native hay-scented fern

Science.gov (United States)

Songlin Fei; Peter Gould; Melanie Kaeser; Kim. Steiner

2010-01-01

The spread and dominance of the invasive native hay-scented fern in the understory is one of the most significant changes to affect the forest ecosystems in the northeastern United States in the last century. We studied changes in the distribution and dynamics of hay-scented fern at a large scale over a 10-yr period in Pennsylvania. The study included 56 stands...

Changes in handgrip force and blood lactate as response to simulated climbing competition

Directory of Open Access Journals (Sweden)

J Gajewski

2009-07-01

Full Text Available The aim of the study was to estimate post-competition changes in handgrip strength and blood lactate in climbers and relationships of the studied variables with declared climbing ability of the tested athletes. Twenty one male climbers volunteered to take part in the experiment. Each subject took part in simulated lead climbing competition on the artificial wall – (difficulty 7a in French scale. The blood lactate concentration was measured pre-climbing and then 3 min and 30 min post-climbing. Grip force of both hands (dominant and non-dominant was measured twice – pre-climbing and 1 min post-climbing (semi-final. Maximum heart rate during climbing reached 181.4±7.7 beats per minute. Lactate concentration amounted to 6.35±1.50 mmol/l and 2.28±0.66 mmol/l 3 min and 30 min post-climbing, respectively. Handgrip force related to body mass (averaged for both hands decreased significantly from 7.39±1.30 N/kg pre-climbing to 6.57±1.05 N/kg 1 min post-climbing. Self reported climbing ability was correlated with lactate concentration and handgrip force, as well. It was demonstrated that athletes reporting higher climbing ability showed better lactate recovery.

Promoting workplace stair climbing: sometimes, not interfering is the best.

Science.gov (United States)

Åvitsland, Andreas; Solbraa, Ane Kristiansen; Riiser, Amund

2017-01-01

Stair climbing is a vigorous activity and can lead to several health benefits. Studies seeking to increase stair climbing in various public locations have shown positive effects, while results from similar studies conducted in the workplace are inconclusive. This study examined stair climbing in the workplace, and monitored effects from a single- and a combined intervention. Interventions were inspired by nudging, the libertarian method of influencing behavior. By quasi-experimental design, stair- and elevator traffic in two office buildings was monitored preceding-, during- and following interventions with stair leading footprints alone, and combined with stair-riser banners. Chi square tests were applied to determine differences between baseline and the subsequent periods. Web-based questionnaires were distributed after follow-up period. Elevators and stairs were used 45 237 times, of which 89.6% was stair use. Intervention site stair climbing at baseline (79.0%) was significantly reduced with footprints (-5.1%, p   0.027). Stair climbing was significantly reduced during the intervention periods. Use of stair leading footprints alone, or combined with stair-riser banners in an attempt to influence stair climbing may be ineffective, or cause a negative reaction, when applied in a workplace with a pre-existing high amount of stair climbing.

Somatic embryogenesis in ferns: a new experimental system.

Science.gov (United States)

Mikuła, Anna; Pożoga, Mariusz; Tomiczak, Karolina; Rybczyński, Jan J

2015-05-01

Somatic embryogenesis has never been reported in ferns. The study showed that it is much easier to evoke the acquisition and expression of embryogenic competence in ferns than in spermatophytes. We discovered that the tree fern Cyathea delgadii offers an effective model for the reproducible and rapid formation of somatic embryos on hormone-free medium. Our study provides cyto-morphological evidence for the single cell origin and development of somatic embryos. Somatic embryogenesis (SE) in both primary and secondary explants was induced on half-strength micro- and macro-nutrients Murashige and Skoog medium without the application of exogenous plant growth regulators, in darkness. The early stage of SE was characterized by sequential perpendicular cell divisions of an individual epidermal cell of etiolated stipe explant. These resulted in the formation of a linear pro-embryo. Later their development resembled that of the zygotic embryo. We defined three morphogenetic stages of fern somatic embryo development: linear, early and late embryonic leaf stage. The transition from somatic embryo to juvenile sporophyte was quick and proceeded without interruption caused by dormancy. Following 9 weeks of culture the efficiency of somatic embryogenesis reached 12-13 embryos per responding explant. Spontaneous formation of somatic embryos and callus production, which improved the effectiveness of the process sevenfold in 10-month-long culture, occurred without subculturing. The tendency for C. delgadii to propagate by SE in vitro makes this species an excellent model for studies relating to asexual embryogenesis and the endogenous hormonal regulation of that process and opens new avenues of experimentation.

Analyis on the vascular epiphytes of tree ferns in a montane rain forest in Costa Rica

OpenAIRE

Jens Bittner; Javier Trejos Zelaya

2009-01-01

The relationships between epiphytes and host specifity are known. We investigated the relation between specific epiphytes and tree fern trunks. Only some epiphytes are frequent or very frequent on tree ferns. Most of the epiphyte species are unspecific on these trunks. Blechnum fragile are the only found exclusively on tree ferns. We also observed different epiphyte communities dependent on the tree fern species and the morphology of the tree trunk.

The fern sporangium: an ultrafast natural catapult

Science.gov (United States)

Noblin, Xavier; Argentina, Mederic; Westbrook, Jared; Llorens, Coraline; Rojas, Nicolas; Dumais, Jacques

2012-02-01

Plants have developed fascinating mechanisms to create ultra fast movements that often reach the upper limit allowed by physical laws. Inspiration for new technologies is one of the reasons for the strong interest for these mechanisms, along with the deep interest of understanding complex, natural systems. The fern sporangium is a capsule that contains the spores, it is surrounded by a row of cells called the annulus which acts as a beam. Due to the water evaporation from its cells, the annulus bends strongly and induces elastic energy storage during an opening phase. The tension in the cells breaks when cavitation bubbles appear in the cells, leading to a fast release of the elastic energy. The fern sporangium then acts as a catapult which ejects rapidly its spores by closing back to the initial closed shape. We have analyzed the slow opening motion and the fast catapulting mechanism. We found that the catapult motion involves two time scales, showing a very original behavior. In man-made catapults, the recoil motion needs to be arrested by a cross bar so that the projectile is released from the arm. We show here that the fern sporangium replaces the essential cross bar by an elegant poroelastic damping, leading to a completely autonomous, efficient device.

Fern Stomatal Responses to ABA and CO2 Depend on Species and Growth Conditions.

Science.gov (United States)

Hõrak, Hanna; Kollist, Hannes; Merilo, Ebe

2017-06-01

Changing atmospheric CO 2 levels, climate, and air humidity affect plant gas exchange that is controlled by stomata, small pores on plant leaves and stems formed by guard cells. Evolution has shaped the morphology and regulatory mechanisms governing stomatal movements to correspond to the needs of various land plant groups over the past 400 million years. Stomata close in response to the plant hormone abscisic acid (ABA), elevated CO 2 concentration, and reduced air humidity. Whether the active regulatory mechanisms that control stomatal closure in response to these stimuli are present already in mosses, the oldest plant group with stomata, or were acquired more recently in angiosperms remains controversial. It has been suggested that the stomata of the basal vascular plants, such as ferns and lycophytes, close solely hydropassively. On the other hand, active stomatal closure in response to ABA and CO 2 was found in several moss, lycophyte, and fern species. Here, we show that the stomata of two temperate fern species respond to ABA and CO 2 and that an active mechanism of stomatal regulation in response to reduced air humidity is present in some ferns. Importantly, fern stomatal responses depend on growth conditions. The data indicate that the stomatal behavior of ferns is more complex than anticipated before, and active stomatal regulation is present in some ferns and has possibly been lost in others. Further analysis that takes into account fern species, life history, evolutionary age, and growth conditions is required to gain insight into the evolution of land plant stomatal responses. © 2017 American Society of Plant Biologists. All Rights Reserved.

Physiological responses to indoor rock-climbing and their relationship to maximal cycle ergometry.

Science.gov (United States)

Sheel, A William; Seddon, Nicholas; Knight, Andrew; McKenzie, Donald C; R Warburton, Darren E

2003-07-01

To quantify the cardiorespiratory responses to indoor climbing during two increasingly difficult climbs and relate them to whole-body dynamic exercise. It was hypothesized that as climbing difficulty increased, oxygen consumption ([V02] and heart rate would increase, and that climbing would require utilization of a significant fraction of maximal cycling values. Elite competitive sport rock climbers (6 male, 3 female) completed two data collection sessions. The first session was completed at an indoor climbing facility, and the second session was an incremental cycle test to exhaustion. During indoor climbing subjects were randomly assigned to climb two routes designated as "harder" or "easier" based on their previous best climb. Subjects wore a portable metabolic system, which allowed measurement of oxygen consumption [V02], minute ventilation ([V02]E), respiratory exchange ratio (RER), and heart rate. During the second session, maximal values for [V02], [V02]E, RER, and heart rate were determined during an incremental cycle test to exhaustion. Heart rate and [VO2], expressed as percent of cycling maximum, were significantly higher during harder climbing compared with easier climbing. During harder climbing, %HR(max) was significantly higher than %[V02] (2max) (89.6% vs 51.2%), and during easier climbing, %HR(max) was significantly higher than %[V02] (2max) (66.9% vs 45.3%). With increasing levels of climbing difficulty, there is a rise in both heart rate and [V02]. However, there is a disproportional rise in heart rate compared with [V02], which we attribute to the fact that climbing requires the use of intermittent isometric contractions of the arm musculature and the reliance of both anaerobic and aerobic metabolism.

Spatial Characteristics of Edible Wild Fern Harvesting in Mountainous Villages in Northeastern Japan Using GPS Tracks

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Toshiya Matsuura

2014-02-01

Full Text Available Wild plants in forests provide valuable living resources for rural communities. The location where local people harvest various species is important to the wise use of forest ecosystem services. Using global positioning system (GPS tracking of harvesters’ activities as well as geographic information system (GIS and a generalized linear model (GLM, this study analyzed the spatial differences among harvesting sites of three popular edible ferns, i.e., ostrich fern (Matteuccia struthiopteris, bracken (Pteridium aquilinum, and royal fern (Osmunda japonica, in mountainous villages of Northeastern Japan. The explanatory variables used were vegetation classes, terrain features, and proximity to roadways. The GLM yielded clear differences in harvesting sites among species that were affected by both the species’ ecological characteristics and human behavior. Ostrich fern was harvested mainly in canopy openings along valley floors, whereas royal fern harvest sites were frequently located in snow avalanche scrublands. Bracken was mainly harvested in deforested areas or young conifer plantations. Whereas ostrich fern and bracken harvest sites were restricted by the accessibility from roadways, this was not the case for royal fern. Potential harvest sites of ferns were estimated with the highest value for bracken. Our results suggest that local harvesters seriously consider various natural and anthropogenic factors to maintain effective and sustainable harvesting.

rbcL gene sequences provide evidence for the evolutionary lineages of leptosporangiate ferns.

Science.gov (United States)

Hasebe, M; Omori, T; Nakazawa, M; Sano, T; Kato, M; Iwatsuki, K

1994-06-07

Pteriodophytes have a longer evolutionary history than any other vascular land plant and, therefore, have endured greater loss of phylogenetically informative information. This factor has resulted in substantial disagreements in evaluating characters and, thus, controversy in establishing a stable classification. To compare competing classifications, we obtained DNA sequences of a chloroplast gene. The sequence of 1206 nt of the large subunit of the ribulose-bisphosphate carboxylase gene (rbcL) was determined from 58 species, representing almost all families of leptosporangiate ferns. Phlogenetic trees were inferred by the neighbor-joining and the parsimony methods. The two methods produced almost identical phylogenetic trees that provided insights concerning major general evolutionary trends in the leptosporangiate ferns. Interesting findings were as follows: (i) two morphologically distinct heterosporous water ferns, Marsilea and Salvinia, are sister genera; (ii) the tree ferns (Cyatheaceae, Dicksoniaceae, and Metaxyaceae) are monophyletic; and (iii) polypodioids are distantly related to the gleichenioids in spite of the similarity of their exindusiate soral morphology and are close to the higher indusiate ferns. In addition, the affinities of several "problematic genera" were assessed.

Reliable Stair Climbing in the Simple Hexapod 'RHex'

National Research Council Canada - National Science Library

Moore, E. Z; Campbell, D; Grimminger, F; Buehler, M

2002-01-01

.... In this paper, we describe an open loop controller that enables our small robot (Length: 51 cm, Width: 20 cm, Height: 12.7 cm. Leg length: 16 cm), to reliably climb a wide range of regular, full-size stairs with no operator input during stair climbing...

Analyis on the vascular epiphytes of tree ferns in a montane rain forest in Costa Rica

Directory of Open Access Journals (Sweden)

Jens Bittner

2009-02-01

Full Text Available The relationships between epiphytes and host specifity are known. We investigated the relation between specific epiphytes and tree fern trunks. Only some epiphytes are frequent or very frequent on tree ferns. Most of the epiphyte species are unspecific on these trunks. Blechnum fragile are the only found exclusively on tree ferns. We also observed different epiphyte communities dependent on the tree fern species and the morphology of the tree trunk.

Sorption equilibrium of mercury onto ground-up tree fern.

Science.gov (United States)

Ho, Yuh-Shan; Wang, Chung-Chi

2008-08-15

The sorption behavior of mercury at different temperatures onto ground-up tree fern was investigated. The experimental results were fitted to two two-parameter isotherms, the Freundlich and Langmuir isotherms, as well as to two three-parameter isotherms, the Redlich-Peterson and Sips isotherms to obtain the characteristic parameters of each model. A comparison of best-fitting was performed using the coefficient of determination and Chi-square test. Both the Langmuir and Redlich-Peterson isotherms were found to well represent the measured sorption data. According to the evaluation using the Langmuir equation, the saturated monolayer sorption capacity of mercury ions onto ground-up tree fern was 26.5 mg/g at 298 K. It was noted that an increase in temperature resulted in a higher mercury ion loading per unit weight of the tree fern. In addition, various thermodynamic parameters, such as DeltaG degrees, DeltaH degrees, and DeltaS degrees, were calculated and compared with the sorption of mercury by other sorbents.

Sorption equilibrium of mercury onto ground-up tree fern

International Nuclear Information System (INIS)

Ho, Y.-S.; Wang, C.-C.

2008-01-01

The sorption behavior of mercury at different temperatures onto ground-up tree fern was investigated. The experimental results were fitted to two two-parameter isotherms, the Freundlich and Langmuir isotherms, as well as to two three-parameter isotherms, the Redlich-Peterson and Sips isotherms to obtain the characteristic parameters of each model. A comparison of best-fitting was performed using the coefficient of determination and Chi-square test. Both the Langmuir and Redlich-Peterson isotherms were found to well represent the measured sorption data. According to the evaluation using the Langmuir equation, the saturated monolayer sorption capacity of mercury ions onto ground-up tree fern was 26.5 mg/g at 298 K. It was noted that an increase in temperature resulted in a higher mercury ion loading per unit weight of the tree fern. In addition, various thermodynamic parameters, such as ΔG o , ΔH o , and ΔS o , were calculated and compared with the sorption of mercury by other sorbents

Sorption equilibrium of mercury onto ground-up tree fern

Energy Technology Data Exchange (ETDEWEB)

Ho, Y.-S. [Department of Chemical Engineering, I-Shou University, No. 1, Section 1, Hsueh-Cheng Road, Ta-Hsu Hsiang, Kaohsiung County 840, Taiwan (China)], E-mail: ysho@isu.edu.tw; Wang, C.-C. [Department of Chemical Engineering, I-Shou University, No. 1, Section 1, Hsueh-Cheng Road, Ta-Hsu Hsiang, Kaohsiung County 840, Taiwan (China)

2008-08-15

The sorption behavior of mercury at different temperatures onto ground-up tree fern was investigated. The experimental results were fitted to two two-parameter isotherms, the Freundlich and Langmuir isotherms, as well as to two three-parameter isotherms, the Redlich-Peterson and Sips isotherms to obtain the characteristic parameters of each model. A comparison of best-fitting was performed using the coefficient of determination and Chi-square test. Both the Langmuir and Redlich-Peterson isotherms were found to well represent the measured sorption data. According to the evaluation using the Langmuir equation, the saturated monolayer sorption capacity of mercury ions onto ground-up tree fern was 26.5 mg/g at 298 K. It was noted that an increase in temperature resulted in a higher mercury ion loading per unit weight of the tree fern. In addition, various thermodynamic parameters, such as {delta}G{sup o}, {delta}H{sup o}, and {delta}S{sup o}, were calculated and compared with the sorption of mercury by other sorbents.

The evolution of vertical climbing in primates: evidence from reaction forces.

Science.gov (United States)

Hanna, Jandy B; Granatosky, Michael C; Rana, Pooja; Schmitt, Daniel

2017-09-01

Vertical climbing is an essential behavior for arboreal animals, yet limb mechanics during climbing are poorly understood and rarely compared with those observed during horizontal walking. Primates commonly engage in both arboreal walking and vertical climbing, and this makes them an ideal taxa in which to compare these locomotor forms. Additionally, primates exhibit unusual limb mechanics compared with most other quadrupeds, with weight distribution biased towards the hindlimbs, a pattern that is argued to have evolved in response to the challenges of arboreal walking. Here we test an alternative hypothesis that functional differentiation between the limbs evolved initially as a response to climbing. Eight primate species were recorded locomoting on instrumented vertical and horizontal simulated arboreal runways. Forces along the axis of, and normal to, the support were recorded. During walking, all primates displayed forelimbs that were net braking, and hindlimbs that were net propulsive. In contrast, both limbs served a propulsive role during climbing. In all species, except the lorisids, the hindlimbs produced greater propulsive forces than the forelimbs during climbing. During climbing, the hindlimbs tends to support compressive loads, while the forelimb forces tend to be primarily tensile. This functional disparity appears to be body-size dependent. The tensile loading of the forelimbs versus the compressive loading of the hindlimbs observed during climbing may have important evolutionary implications for primates, and it may be the case that hindlimb-biased weight support exhibited during quadrupedal walking in primates may be derived from their basal condition of climbing thin branches. © 2017. Published by The Company of Biologists Ltd.

Penyelesaian Masalah 8-Puzzle dengan Algoritma Steepest-Ascent Hill Climbing

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David Abraham

2016-03-01

Full Text Available 8 puzzle merupakan salah satu implementasi dari Artificial Intelegence. Dalam proses penyelesaiannya banyak terdapat algoritma-algoritma pencarian yang dapat diterapkan. Solusi 8 puzzle akan lebih cepat diperoleh jika digunakan prinsip array dengan variasi algoritma Steepest-Ascent Hill Climbing (Hill Climbing dengan memilih kemiringan yang paling tajam / curam dengan parameter heuristik posisi yang benar dan heuristik jarak serta dikombinasikan dengan LogList sebagai penyimpanan state state yang pernah dilalui untuk menanggulangi permasalah pada algoritma hill climbing itu sendiri dan terhindar dari looping state yang pernah dilalui. Metode-metode yang termasuk ke dalam teknik pencarian yang berdasarkan pada fungsi heuristik salah satu diantaranya adalah Hill Climbing, Best First Search, A* (A Bintang. Loglist merupakan tempat penyimpanan setiap kunjungan dari state-state puzzle yang telah dilakukan untuk menghindari looping atau pengulangan terhadap state yang pernah dilalui. Untuk menanggulangi permasalahan pada SteepestAscent Hill Climbing.

Alvaro Fernández Pérez

Directory of Open Access Journals (Sweden)

Díaz Piedrahita Santiago

1995-11-01

Full Text Available Fue el Dr. Fernández miembro destacado de la comunidad botánica latinoamericana formada hacia la mitad del siglo, y en Colombia desempeñó un papel importante como miembro de planta del Herbario Nacional Colombiano y del Instituto de Ciencias Naturales de la Facultad de Ciencias de la Universidad Nacional de Colombia. Nació el Dr. Fernández el 11 de febrero de 1920 en la procera ciudad de Popayán, donde tras adelantar los estudios primarios y secundarios obtuvo en 1940 el título de bachiller en el Liceo de la Universidad del Cauca; cumplida esta etapa se desplazó a Bogotá, ingresando a la Universidad Nacional donde completó el plan de estudios de la carrera de Farmacia e inició el curso del doctorado que se ofrecía para la época.

In Vitro Conservation of Some Threatened and Economically Important Ferns Belonging to the Indian Subcontinent

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Shastri P. Shukla

2014-01-01

Full Text Available This study was undertaken to identify methods of mass multiplication for five ornamental, economically important ferns (Nephrolepis biserrata (Sw. Schott., N. cordifolia cv. ‘‘duffii’’ (L. Presl., N. exaltata cv. bostoniensis (L. Schott., Pteris vittata L., and Cyclosorus dentatus Link., and three threatened ferns, namely, Cyathea spinulosa Wall. ex. Hook, Pityrogramma calomelanos (L. Link., and Microsorum punctatum (L. Schott., through in vitro techniques. Collections were made from different biodiversity zones of India including Northeast Himalayas, Kumaon Himalayas, and Western Ghat and successfully introduced and grown in a fern-house. Aseptic cultures were raised at the morphogenic level of callus, axillary shoot, multiple shoot, and rooted plants. An optimized medium is described for each fern species. Plantlets were also produced from spore culture of Cyathea spinulosa and successfully hardened under fern house conditions.

A Wheel-based Stair-climbing Robot with a Hopping Mechanism

OpenAIRE

Kikuchi, Koki; Bushida, Naoki; Sakaguchi, Keisuke; Chiba, Yasuhiro; Otsuka, Hiroshi; Saito, Yusuke; Hirano, Masamitsu; Kobayashi, Shunya

2010-01-01

We introduced a wheel-based stair-climbing robot with a hopping mechanism for stairclimbing. The robot, consisting of two body parts connected by springs, climbed stairs quickly, softly, and economically by using the vibration of a two-degrees-of-freedom system. In the future, we intend to shorten the required tread length by controlling the wire tension and minimizing the body length to realize a practical stair-climbing robot.

The first fossil of a bolbitidoid fern belongs to the early-divergent lineages of Elaphoglossum (Dryopteridaceae).

Science.gov (United States)

Lóriga, Josmaily; Schmidt, Alexander R; Moran, Robbin C; Feldberg, Kathrin; Schneider, Harald; Heinrichs, Jochen

2014-09-01

• Closing gaps in the fossil record and elucidating phylogenetic relationships of mostly incomplete fossils are major challenges in the reconstruction of the diversification of fern lineages through time. The cosmopolitan family Dryopteridaceae represents one of the most species-rich families of leptosporangiate ferns, yet its fossil record is sparse and poorly understood. Here, we describe a fern inclusion in Miocene Dominican amber and investigate its relationships to extant Dryopteridaceae.• The morphology of the fossil was compared with descriptions of extant ferns, resulting in it being tentatively assigned to the bolbitidoid fern genus Elaphoglossum. This assignment was confirmed by reconstructing the evolution of the morphological characters preserved in the inclusion on a molecular phylogeny of 158 extant bolbitidoid ferns. To assess the morphology-based assignment of the fossil to Elaphoglossum, we examined DNA-calibrated divergence time estimates against the age of the amber deposits from which it came.• The fossil belongs to Elaphoglossum and is the first of a bolbitidoid fern. Its assignment to a particular section of Elaphoglossum could not be determined; however, sects. Lepidoglossa, Polytrichia, and Setosa can be discounted because the fossil lacks subulate scales or scales with acicular marginal hairs. Thus, the fossil might belong to either sects. Amygdalifolia, Wrightiana, Elaphoglossum, or Squamipedia or to an extinct lineage.• The discovery of a Miocene Elaphoglossum fossil provides remarkable support to current molecular clock-based estimates of the diversification of these ferns. © 2014 Botanical Society of America, Inc.

Biologically-inspired synthetic dry adhesives for wall-climbing robots

Science.gov (United States)

Murphy, Michael P.

Animals such as insects, spiders, and lizards are capable of clinging to and climbing on a variety of surfaces, from rough stone to smooth silicon. Hairy microscale arrays of structures on their feet conform to surface roughness to create millions of points of contact, creating a large overall contact area. Weak intermolecular forces (van der Waals forces) between each fiber tip and the surface sum to large overall forces due to the high number of contacts. In this work we present the fabrication, characterization, and demonstration of synthetic polyurethane fibrillar adhesives inspired by these animals. Angled polymer micro-fiber arrays are fabricated and characterized. A tip modification technique is presented which enables fabrication of fibers with flat mushroom shaped tips which greatly increase the adhesion of the fibers, up to 5N/cm 2 (normal direction), and with a magnitude within the range of geckos (10 N/cm2) in the shear direction on smooth surfaces. We present a fabrication technique to create fibers with angled flat mushroom-shaped tips which replicate the directional characteristics of geckos, gripping in one direction (within the range of gecko adhesion) and releasing easily in the other. Multilevel hierarchical structures with specialized tips for roughness adaptation are also presented. Fiber hierarchies from the millimeter scale to the sub-micron scale are demonstrated, including three-level fiber fabrication with specialized tips. Hierarchical structures demonstrate up to 5 times the adhesion of an unstructured sample, and requiring up to 10 times the detachment energy. Finally, an agile, wireless, palm-sized wall climbing robot which uses the synthetic fibrillar dry adhesives to climb is presented. Waalbot , named after the van der Waals forces it uses to climb, exploits the attachment and detachment characteristics of the developed dry adhesives, capabilities include climbing smooth surfaces such as glass in any orientation on any surface slope

SURVEY OF ORNAMENTAL FERNS, THEIR MORPHOLOGY AND ...

African Journals Online (AJOL)

ornamental ferns for environmental management and economic values. ... little variations in the structures of rhizome except in Phymatodes .... forms such as erect, tall, open, bushy and .... linear leaflet with acute apex and flat, glabrous lamina.

Research on Dynamics and Stability in the Stairs-Climbing of a Tracked Mobile Robot

Directory of Open Access Journals (Sweden)

Weijun Tao

2012-10-01

Full Text Available Aiming at the functional requirement of climbing up the stairs, the dynamics and stability during a tracked mobile robot's climbing of stairs is studied. First, from the analysis of its cross-country performance, the mechanical structure of the tracked mobile robot is designed and the hardware composition of its control system is given. Second, based on the analysis to its stairs-climbing process, the dynamical model of stairs-climbing is established by using the classical mechanics method. Next, the stability conditions for its stairs-climbing are determined and an evaluation method of its stairs-climbing stability is proposed, based on a mechanics analysis on the robot's backwards tumbling during the stairs-climbing process. Through simulation and experiments, the effectiveness of the dynamical model and the stability evaluation method of the tracked mobile robot in stairs-climbing is verified, which can provide design and analysis foundations for the tracked mobile robots' stairs-climbing.

In vitro mutagenesis of commercial fern, Asplenium nidus from spores

International Nuclear Information System (INIS)

Norazlina Noordin

2004-01-01

Asplenium is a largest, most diverse fern genera. One of the common species is Asplenium nidus, well known as Bird's-nest fern, a medium to large fern with erect, stout, unbranched rhizomes. In creating variability of ferns for the benefit of the ornamental plant industry, in vitro mutagenesis is used. In this study, spores of Asplenium nidus were collected from frond bearing mature sporangia. Spores were cultured in modified 1/2 MS basal medium supplemented with various combinations of 6-Benzylaminopurine (BAP) and Naphtalene Acetic Acid (NAA). Spore cultures were incubated in incubation room at 24 degree C with 16 hours photoperiod (3500 lux). It was found that, the most effective combinations were 1 mg/1 BAP + 0. 1 mg/1 NAA and 2mg/1 BAP + 0. 1 mg/1 NAA. Prothallus was formed after 10 days of cultures and gametophytes were formed 1 month later. These gametophytes were irradiated with Gamma ray at doses of 0, 20, 90, 120, 150 and 180 Gy. From the preliminary result obtained from this study, for generating variations and desired phenotypic expression for Asplenium nidus, recommended doses for in vitro mutagenesis using spores are between 90 Gy to 150 Gy. Gametophytes were subcultured at monthly interval to ensure further development and propagation. Frequent monitoring for any changes in the morphology of the irradiated Asplenium nidus plants were carried out. (Author)

Changes in soil solution chemistry of Andisols following invasion by bracken fern

Science.gov (United States)

J. L. Johnson-Maynard; P. A. McDaniel; D. E. Ferguson; A. L. Falen

1998-01-01

Disturbed areas within the Grand Fir Mosaic (GFM) ecosystem of northern Idaho show little to no natural conifer regeneration. Clear-cut sites are invaded quickly by bracken fern successional communities and seem to be in an arrested state of secondary succession. This study compared the soil solution composition of Andisols supporting bracken fern successional...

A Kinect-sensor-based Tracked Robot for Exploring and Climbing Stairs

Directory of Open Access Journals (Sweden)

I-Hsum Li

2014-05-01

Full Text Available This paper focuses on the stair-climbing problem for a tracked robot. The tracked robot designed in this paper has the ability to explore stairs in an unknown indoor environment, climbing up and down the stairs, keeping balance while climbing, and successfully landing on the stair platform. Intelligent algorithms are proposed to explore and align stairs, and a fuzzy controller is introduced to stabilize the tracked robot's movement during the exploration. An inexpensive Kinect depth sensor is the only equipment needed for all the control modes. Finally, experiments illustrate the effectiveness of the proposed approach for climbing stairs.

Arsenic accumulation by two brake ferns growing on an arsenic mine and their potential in phytoremediation.

Science.gov (United States)

Wei, Chao-Yang; Chen, Tong-Bin

2006-05-01

In an area near an arsenic mine in Hunan Province of south China, soils were often found with elevated arsenic levels. A field survey was conducted to determine arsenic accumulation in 8 Cretan brake ferns (Pteris cretica) and 16 Chinese brake ferns (Pteris vittata) growing on these soils. Three factors were evaluated: arsenic concentration in above ground parts (fronds), arsenic bioaccumulation factor (BF; ratio of arsenic in fronds to soil) and arsenic translocation factor (TF; ratio of arsenic in fronds to roots). Arsenic concentrations in the fronds of Chinese brake fern were 3-704 mg kg-1, the BFs were 0.06-7.43 and the TFs were 0.17-3.98, while those in Cretan brake fern were 149-694 mg kg-1, 1.34-6.62 and 1.00-2.61, respectively. Our survey showed that both ferns were capable of arsenic accumulation under field conditions. With most of the arsenic being accumulated in the fronds, these ferns have potential for use in phytoremediation of arsenic contaminated soils.

Non-synaptic signaling from cerebellar climbing fibers modulates Golgi cell activity.

Science.gov (United States)

Nietz, Angela K; Vaden, Jada H; Coddington, Luke T; Overstreet-Wadiche, Linda; Wadiche, Jacques I

2017-10-13

Golgi cells are the principal inhibitory neurons at the input stage of the cerebellum, providing feedforward and feedback inhibition through mossy fiber and parallel fiber synapses. In vivo studies have shown that Golgi cell activity is regulated by climbing fiber stimulation, yet there is little functional or anatomical evidence for synapses between climbing fibers and Golgi cells. Here, we show that glutamate released from climbing fibers activates ionotropic and metabotropic receptors on Golgi cells through spillover-mediated transmission. The interplay of excitatory and inhibitory conductances provides flexible control over Golgi cell spiking, allowing either excitation or a biphasic sequence of excitation and inhibition following single climbing fiber stimulation. Together with prior studies of spillover transmission to molecular layer interneurons, these results reveal that climbing fibers exert control over inhibition at both the input and output layers of the cerebellar cortex.

Therapeutic use of sport climbing for patients with multiple sclerosis

Directory of Open Access Journals (Sweden)

Ana Ožura

2009-05-01

Full Text Available Sport climbing is a form of exercise that requires complex and variable movement. Because of the use of the so-called "top-rope system", this is a safe activity appropriate for individuals with physical disabilities. Therefore, climbing might prove to be an effective form of therapy for patients with multiple sclerosis. Multiple sclerosis is a chronic neurological disease that may include motor and cognitive deficits as well as affective disturbances. The illness is characterized by multifocal areas of brain damage (plaques, as consequence of autoimmune inflammation. Sport climbing might be a potentially useful activity for treating spasticity, improving a person's self image and certain aspects of cognition, such as attention and executive functions, as well as for managing emotional disturbances. All of the above are areas where patients with multiple sclerosis might be in need of assistance. The article also describes the experience of a patient with multiple sclerosis who was enrolled in our climbing program. Future research is needed to evaluate the effect of climbing therapy for patients with multiple sclerosis.

Finding paradise: cues directing the migration of the waterfall climbing Hawaiian gobioid Sicyopterus stimpsoni.

Science.gov (United States)

Leonard, G; Maie, T; Moody, K N; Schrank, G D; Blob, R W; Schoenfuss, H L

2012-07-01

A series of waterfall-climbing trials were conducted to identify cues that direct the climbing of juvenile Sicyopterus stimpsoni. In the first experiment, whether climbing juveniles preferentially ascend water sources with conspecifics or whether the presence of just stream water is sufficient to attract fish to ascend a climbing path were assessed. In the second experiment, whether climbing juveniles create a trail of mucus that facilitates the ability of conspecifics to follow their lead was determined. The results indicate that juvenile S. stimpsoni are less likely to climb in waters devoid of organic cues but are strongly attracted to stream water with or without the odour of conspecifics. Once climbing, performance did not differ for juveniles climbing in differing water choices, suggesting an all-or-nothing commitment once climbing commences. Climbing S. stimpsoni did produce a mucous trail while climbing that was associated with a mucous gland that dramatically increases in size just prior to juveniles gaining the ability to climb. The trail was not followed closely by subsequent juveniles traversing the same channel, however, suggesting only weak trail-following in waterfall climbing S. stimpsoni. Previous genetic studies suggest that juvenile S. stimpsoni do not home to natal streams in the face of strong near-shore oceanic currents. Instead, these fish appear primarily to rely on cues that suggest the presence of organic growth in streams, a factor that may indicate suitable habitat in an ever-changing stream environment but which may also be vulnerable to interference through human activity. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

Glycoside Hydrolase (GH) 45 and 5 Candidate Cellulases in Aphelenchoides besseyi Isolated from Bird?s-Nest Fern

OpenAIRE

Wu, Guan-Long; Kuo, Tzu-Hao; Tsay, Tung-Tsuan; Tsai, Isheng J.; Chen, Peichen J.

2016-01-01

Five Aphelenchoides besseyi isolates collected from bird's-nest ferns or rice possess different parasitic capacities in bird's-nest fern. Two different glycoside hydrolase (GH) 45 genes were identified in the fern isolates, and only one was found in the rice isolates. A Abe GH5-1 gene containing an SCP-like family domain was found only in the fern isolates. Abe GH5-1 gene has five introns suggesting a eukaryotic origin. A maximum likelihood phylogeny revealed that Abe GH5-1 is part of the nem...

Are rates of species diversification and body size evolution coupled in the ferns?

Science.gov (United States)

Testo, Weston L; Sundue, Michael A

2018-03-01

Understanding the relationship between phenotypic evolution and lineage diversification is a central goal of evolutionary biology. To extend our understanding of the role morphological evolution plays in the diversification of plants, we examined the relationship between leaf size evolution and lineage diversification across ferns. We tested for an association between body size evolution and lineage diversification using a comparative phylogenetic approach that combined a time-calibrated phylogeny and leaf size data set for 2654 fern species. Rates of leaf size change and lineage diversification were estimated using BAMM, and rate correlations were performed for rates obtained for all families and individual species. Rates and patterns of rate-rate correlation were also analyzed separately for terrestrial and epiphytic taxa. We find no significant correlation between rates of leaf area change and lineage diversification, nor was there a difference in this pattern when growth habit is considered. Our results are consistent with the findings of an earlier study that reported decoupled rates of body size evolution and diversification in the Polypodiaceae, but conflict with a recent study that reported a positive correlation between body size evolution and lineage diversification rates in the tree fern family Cyatheaceae. Our findings indicate that lineage diversification in ferns is largely decoupled from shifts in body size, in contrast to several other groups of organisms. Speciation in ferns appears to be primarily driven by hybridization and isolation along elevational gradients, rather than adaptive radiations featuring prominent morphological restructuring. The exceptional diversity of leaf morphologies in ferns appears to reflect a combination of ecophysiological constraints and adaptations that are not key innovations. © 2018 Botanical Society of America.

Pregnant Women in Sport Climbing - Is there a Higher Risk for Preterm Birth?

Science.gov (United States)

Drastig, Jan; Hillebrandt, David; Rath, Werner; Küpper, Thomas

2017-02-01

Sport climbing is a popular recreational sport with an increasing proportion of female athletes. International recommendations emphasize the physical and mental benefits of regular sport activity during any uncomplicated pregnancy. In this context, sport climbing is associated with a high risk potential.The aim of this study was to examine if there is a higher risk for preterm birth in active climbing athletes.Original manuscript.A retrospective self-report online survey in the German language collected data between September 2012 and November 2013. In addition to anthropometric and demographic data, data on climbing experience, preferred climbing discipline, skill level and changes of climbing habits during pregnancy, known risk factors for preterm birth and information on delivery and the newborn were requested. The rate of preterm birth of the survey was tested with Fisher's exact test with information from the German Federal Statistical Office.Sample size was 32. 72% had a university degree, 81% were primiparous, all were singleton pregnancies. A 33 rd questionnaire was excluded because of described preeclampsia. Age ranged between 21 and 39 years, climbing experience before pregnancy between 2 and 24 years, and skill level before pregnancy between 4 and 7 on the UIAA scale (International Climbing and Mountaineering Federation). Half of the women climbed until the 36 th week and 90% adjusted their climbing habits mostly by reducing climbing difficulty and doing more top roping. 2 preterm births in the 36 th week of gestation were found (2 from 15, p=0.36). According to the data from the German Federal Statistical Office, 8.9% births in the year 2013 in Germany were preterm.This is the first study investigating the risk of preterm birth in recreational sport climbing athletes. No significantly higher proportion of preterm birth could be found. Limitations are small sample size and high social status of participants. What is known about the subject: Sport

The Mechanical Properties of a Wall-Climbing Caterpillar Robot: Analysis and Experiment

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Kun Wang

2013-01-01

Full Text Available This paper builds the kinematic model of a wall-climbing caterpillar robot to reveal the validity and the benefits of the closed-chain kinematics of the four-linkage mechanism to a crawling gait. The caterpillar robot can climb on a vertical wall by coordinating the rotations of one active joint and three passive joints. The mechanical property of the closed-chain kinematics of the four-linkage model is analysed. Furthermore, the relation between the driving joint torque and joint angle in the wall-climbing process is deduced based on the coplanar arbitrary force system. Afterwards, the joint control method is discussed in order to coordinate the rotation of the four joints so as to realize a reasonable wall climbing gait. To testify to the availability of the closed-chain four-linkage model, a wall-climbing caterpillar robot is developed with three different adhesion modules based on the vibrating suction method. A successful wall-climbing test confirms both the practicality of the four-linkage model and the validity of the adhesion modules based on the vibrating suction method. The results also show the reasonableness of the driving joint selection rule for ensuring a safe and reliable wall-climbing procedure.

Ecological anatomy of ferns fronds

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Nina M. Derzhavina

2014-04-01

Full Text Available Structural types of frond anatomy are distinguished on the basis of investigation of 30 species of homosporous ferns and with regard for literature: hydromorphic, hygromorphic, mesomorphic, subxeromorphic, and subsucculent (cryptic succulent. Following frond traits are of highest adaptive value: their area and thickness, type of mesophyll, dry weight of an area unit – specific superficial density, cellular volume, and number of cells per unit of frond area.

Non-linear growth in tree ferns, Dicksonia antarctica and Cyathea australis.

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Blair, David P; Blanchard, Wade; Banks, Sam C; Lindenmayer, David B

2017-01-01

Tree ferns are an important structural component of forests in many countries. However, because their regeneration is often unrelated to major disturbances, their age is often difficult to determine. In addition, rates of growth may not be uniform, which further complicates attempts to determine their age. In this study, we measured 5 years of growth of Cyathea australis and Dicksonia antarctica after a large wildfire in 2009 in south-eastern Australia. We found growth rates of these two species were unaffected by aspect and elevation but slope had a minor effect with D. antarctica growing 0.3mm faster for each additional degree of slope. Geographic location influenced growth in both species by up to 12 - 14mm/yr. The most consistent factor influencing growth rate, however, was initial height at the time of the 2009 fire; a finding consistent in both species and all geographic locations. For both tree fern species, individuals that were taller at the commencement of the study had greater overall growth for the duration of the study. This effect did not decrease even among the tallest tree ferns in our study (up to 6 metres tall). Overall, Cyathea australis averaged 73 (± 22)mm/year of growth (± 1SD), with the rate increasing 5mm/yr per metre of additional height. Dicksonia antarctica averaged 33 (± 13)mm/year, increasing by 6mm/yr/m. Growth rates dependent on initial height were unexpected and we discuss possible reasons for this finding. Variable growth rates also suggest that common age estimation methods of dividing height by average growth rate are likely to underestimate the age of short tree ferns, while overestimating the age of tall tree ferns, particularly if they have been subject to a fire.

Non-linear growth in tree ferns, Dicksonia antarctica and Cyathea australis.

Directory of Open Access Journals (Sweden)

David P Blair

Full Text Available Tree ferns are an important structural component of forests in many countries. However, because their regeneration is often unrelated to major disturbances, their age is often difficult to determine. In addition, rates of growth may not be uniform, which further complicates attempts to determine their age. In this study, we measured 5 years of growth of Cyathea australis and Dicksonia antarctica after a large wildfire in 2009 in south-eastern Australia. We found growth rates of these two species were unaffected by aspect and elevation but slope had a minor effect with D. antarctica growing 0.3mm faster for each additional degree of slope. Geographic location influenced growth in both species by up to 12 - 14mm/yr. The most consistent factor influencing growth rate, however, was initial height at the time of the 2009 fire; a finding consistent in both species and all geographic locations. For both tree fern species, individuals that were taller at the commencement of the study had greater overall growth for the duration of the study. This effect did not decrease even among the tallest tree ferns in our study (up to 6 metres tall. Overall, Cyathea australis averaged 73 (± 22mm/year of growth (± 1SD, with the rate increasing 5mm/yr per metre of additional height. Dicksonia antarctica averaged 33 (± 13mm/year, increasing by 6mm/yr/m. Growth rates dependent on initial height were unexpected and we discuss possible reasons for this finding. Variable growth rates also suggest that common age estimation methods of dividing height by average growth rate are likely to underestimate the age of short tree ferns, while overestimating the age of tall tree ferns, particularly if they have been subject to a fire.

Phylogeny of Marsileaceous Ferns and Relationships of the Fossil Hydropteris pinnata Reconsidered.

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Pryer

1999-09-01

Recent phylogenetic studies have provided compelling evidence that confirms the once disputed hypothesis of monophyly for heterosporous leptosporangiate ferns (Marsileaceae and Salviniaceae). Hypotheses for relationships among the three genera of Marsileaceae (Marsilea, Regnellidium, and Pilularia), however, have continued to be in conflict. The phylogeny of Marsileaceae is investigated here using information from morphology and rbcL sequence data. In addition, relationships among all heterosporous ferns, including the whole-plant fossil Hydropteris pinnata are reconsidered. Data sets of 71 morphological and 1239 rbcL characters for 23 leptosporangiate ferns, including eight heterosporous ingroup taxa and 15 homosporous outgroup taxa, were subjected to maximum parsimony analysis. Morphological analyses were carried out both with and without the fossil Hydropteris, and it was excluded from all analyses with rbcL data. An annotated list of the 71 morphological characters is provided in the appendix. For comparative purposes, the Rothwell and Stockey (1994) data set was also reanalyzed here. The best estimate of phylogenetic relationships for Marsileaceae in all analyses is that Pilularia and Regnellidium are sister taxa and Marsilea is sister to that clade. Morphological synapomorphies for various nodes are discussed. Analyses that included Hydropteris resulted in two most-parsimonious trees that differ only in the placement of the fossil. One topology is identical to the relationship found by Rothwell and Stockey (1994), placing the fossil sister to the Azolla plus Salvinia clade. The alternative topology places Hydropteris as the most basal member of the heterosporous fern clade. Equivocal interpretations for character evolution in heterosporous ferns are discussed in the context of these two most-parsimonious trees. Because of the observed degree of character ambiguity, the phylogenetic placement of Hydropteris is best viewed as unresolved, and recognition of the

FERN - a Java framework for stochastic simulation and evaluation of reaction networks.

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Erhard, Florian; Friedel, Caroline C; Zimmer, Ralf

2008-08-29

Stochastic simulation can be used to illustrate the development of biological systems over time and the stochastic nature of these processes. Currently available programs for stochastic simulation, however, are limited in that they either a) do not provide the most efficient simulation algorithms and are difficult to extend, b) cannot be easily integrated into other applications or c) do not allow to monitor and intervene during the simulation process in an easy and intuitive way. Thus, in order to use stochastic simulation in innovative high-level modeling and analysis approaches more flexible tools are necessary. In this article, we present FERN (Framework for Evaluation of Reaction Networks), a Java framework for the efficient simulation of chemical reaction networks. FERN is subdivided into three layers for network representation, simulation and visualization of the simulation results each of which can be easily extended. It provides efficient and accurate state-of-the-art stochastic simulation algorithms for well-mixed chemical systems and a powerful observer system, which makes it possible to track and control the simulation progress on every level. To illustrate how FERN can be easily integrated into other systems biology applications, plugins to Cytoscape and CellDesigner are included. These plugins make it possible to run simulations and to observe the simulation progress in a reaction network in real-time from within the Cytoscape or CellDesigner environment. FERN addresses shortcomings of currently available stochastic simulation programs in several ways. First, it provides a broad range of efficient and accurate algorithms both for exact and approximate stochastic simulation and a simple interface for extending to new algorithms. FERN's implementations are considerably faster than the C implementations of gillespie2 or the Java implementations of ISBJava. Second, it can be used in a straightforward way both as a stand-alone program and within new

A Gompertz regression model for fern spores germination

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Gabriel y Galán, Jose María

2015-06-01

Full Text Available Germination is one of the most important biological processes for both seed and spore plants, also for fungi. At present, mathematical models of germination have been developed in fungi, bryophytes and several plant species. However, ferns are the only group whose germination has never been modelled. In this work we develop a regression model of the germination of fern spores. We have found that for Blechnum serrulatum, Blechnum yungense, Cheilanthes pilosa, Niphidium macbridei and Polypodium feuillei species the Gompertz growth model describe satisfactorily cumulative germination. An important result is that regression parameters are independent of fern species and the model is not affected by intraspecific variation. Our results show that the Gompertz curve represents a general germination model for all the non-green spore leptosporangiate ferns, including in the paper a discussion about the physiological and ecological meaning of the model.La germinación es uno de los procesos biológicos más relevantes tanto para las plantas con esporas, como para las plantas con semillas y los hongos. Hasta el momento, se han desarrollado modelos de germinación para hongos, briofitos y diversas especies de espermatófitos. Los helechos son el único grupo de plantas cuya germinación nunca ha sido modelizada. En este trabajo se desarrolla un modelo de regresión para explicar la germinación de las esporas de helechos. Observamos que para las especies Blechnum serrulatum, Blechnum yungense, Cheilanthes pilosa, Niphidium macbridei y Polypodium feuillei el modelo de crecimiento de Gompertz describe satisfactoriamente la germinación acumulativa. Un importante resultado es que los parámetros de la regresión son independientes de la especie y que el modelo no está afectado por variación intraespecífica. Por lo tanto, los resultados del trabajo muestran que la curva de Gompertz puede representar un modelo general para todos los helechos leptosporangiados

Forest climbing plants of West Africa: diversity, ecology and management

NARCIS (Netherlands)

Bongers, F.J.J.M.; Parren, M.P.E.; Traoré, D.

2005-01-01

Climbing plants, including lianas, represent a fascinating component of the ecology of tropical forests. This book focuses on the climbing plants of West African forests. Based on original research, it presents information on the flora (including a checklist), diversity (with overviews at several

Abiotic factors drives floristic variations of fern's metacommunity in an Atlantic Forest remnant.

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Costa, L E N; Farias, R P; Santiago, A C P; Silva, I A A; Barros, I C L

2018-02-15

We analyzed floristic variations in fern's metacommunity at the local scale and their relationship with abiotic factors in an Atlantic Forest remnant of northeastern Brazil. Floristic and environmental variations were accessed on ten plots of 10 × 20 m. We performed cluster analyses, based on Bray-Curtis dissimilarity index to establish the floristic relationship. The influence of abiotic factors: luminosity, temperature, relative air humidity and relative soil moisture was evaluated from a redundancy analysis. We found 24 species belonging to 20 genera and 12 families. The fern's flora showed high floristic heterogeneity (>75% for most of the plot's associations). The fern's metacommunity was structured along an abiotic gradient modulated by temperature, luminosity, and relative soil moisture.

Evolution of the rpoB-psbZ region in fern plastid genomes: notable structural rearrangements and highly variable intergenic spacers.

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Gao, Lei; Zhou, Yuan; Wang, Zhi-Wei; Su, Ying-Juan; Wang, Ting

2011-04-13

The rpoB-psbZ (BZ) region of some fern plastid genomes (plastomes) has been noted to go through considerable genomic changes. Unraveling its evolutionary dynamics across all fern lineages will lead to clarify the fundamental process shaping fern plastome structure and organization. A total of 24 fern BZ sequences were investigated with taxon sampling covering all the extant fern orders. We found that: (i) a tree fern Plagiogyria japonica contained a novel gene order that can be generated from either the ancestral Angiopteris type or the derived Adiantum type via a single inversion; (ii) the trnY-trnE intergenic spacer (IGS) of the filmy fern Vandenboschia radicans was expanded 3-fold due to the tandem 27-bp repeats which showed strong sequence similarity with the anticodon domain of trnY; (iii) the trnY-trnE IGSs of two horsetail ferns Equisetum ramosissimum and E. arvense underwent an unprecedented 5-kb long expansion, more than a quarter of which was consisted of a single type of direct repeats also relevant to the trnY anticodon domain; and (iv) ycf66 has independently lost at least four times in ferns. Our results provided fresh insights into the evolutionary process of fern BZ regions. The intermediate BZ gene order was not detected, supporting that the Adiantum type was generated by two inversions occurring in pairs. The occurrence of Vandenboschia 27-bp repeats represents the first evidence of partial tRNA gene duplication in fern plastomes. Repeats potentially forming a stem-loop structure play major roles in the expansion of the trnY-trnE IGS.

Evolution of the rpoB-psbZ region in fern plastid genomes: notable structural rearrangements and highly variable intergenic spacers

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Su Ying-Juan

2011-04-01

Full Text Available Abstract Background The rpoB-psbZ (BZ region of some fern plastid genomes (plastomes has been noted to go through considerable genomic changes. Unraveling its evolutionary dynamics across all fern lineages will lead to clarify the fundamental process shaping fern plastome structure and organization. Results A total of 24 fern BZ sequences were investigated with taxon sampling covering all the extant fern orders. We found that: (i a tree fern Plagiogyria japonica contained a novel gene order that can be generated from either the ancestral Angiopteris type or the derived Adiantum type via a single inversion; (ii the trnY-trnE intergenic spacer (IGS of the filmy fern Vandenboschia radicans was expanded 3-fold due to the tandem 27-bp repeats which showed strong sequence similarity with the anticodon domain of trnY; (iii the trnY-trnE IGSs of two horsetail ferns Equisetum ramosissimum and E. arvense underwent an unprecedented 5-kb long expansion, more than a quarter of which was consisted of a single type of direct repeats also relevant to the trnY anticodon domain; and (iv ycf66 has independently lost at least four times in ferns. Conclusions Our results provided fresh insights into the evolutionary process of fern BZ regions. The intermediate BZ gene order was not detected, supporting that the Adiantum type was generated by two inversions occurring in pairs. The occurrence of Vandenboschia 27-bp repeats represents the first evidence of partial tRNA gene duplication in fern plastomes. Repeats potentially forming a stem-loop structure play major roles in the expansion of the trnY-trnE IGS.

Research on a Micro Flip Robot That Can Climb Stairs

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Jianzhong Wang

2016-03-01

Full Text Available Micro mobile robots (MMRs can operate in rugged, narrow or dangerous regions; thus, they are widely used in numerous areas including surveillance, rescue and exploration. In urban environments, stairs are common obstacles, ones that such robots find difficult to manoeuvre over. The authors analysed the research status of MMRs, particularly in terms of difficulties when performing stair climbing and present a novel type of MMR called the micro flip robot (MFRobot. A support arm subassembly was added to the centre of a wheeled chassis; using this structure, the MFRobot can climb stairs when a flipping mode is utilized. Based on this structure, the authors established a kinematic model of the stair-climbing process and analysed the force conditions for the key status, contributing to the existing knowledge of robot design. An MFRobot prototype was produced and the stair-climbing experiments, as well as experiments on manoeuvring through rubble regions and slope surfaces, were conducted. The results show that the MFRobot can rapidly climb common stairs and can easily manoeuvre through a rubble region. The maximum slope angle the robot can climb was shown to be about 35° for concrete and wooden slope surfaces. In the case where the robot needed to be equipped with sensors, particularly a camera, the camera was equipped on the support arm of robot. The MFRobot prototype weighs 2.5 kg and is easily transportable. This structure can resolve contradictions between portability and performance in terms of overcoming obstacles; in addition, operational effectiveness can be improved using this structure.

A Kinect-sensor-based Tracked Robot for Exploring and Climbing Stairs

OpenAIRE

I-Hsum Li; Wei-Yen Wang; Chien-Kai Tseng

2014-01-01

This paper focuses on the stair-climbing problem for a tracked robot. The tracked robot designed in this paper has the ability to explore stairs in an unknown indoor environment, climbing up and down the stairs, keeping balance while climbing, and successfully landing on the stair platform. Intelligent algorithms are proposed to explore and align stairs, and a fuzzy controller is introduced to stabilize the tracked robot's movement during the exploration. An inexpensive Kinect depth sensor is...

The acute toxicity of the metaldehyde on the climbing perch

Science.gov (United States)

Wahida Mohamad Ismail, Syamimi; Aini Dahalan, Farrah; Zakaria, Ammar; Mad Shakaff, Ali Yeon; Aqlima Ahmad, Siti; Shukor, Mohd Yunus Abd; Khalizan Sabullah, Mohd; Khalil, Khalilah Abdul; Jalil, Mohd Faizal Ab

2018-03-01

In Asia, Climbing perch (Anabas testudineus) is commonly found in paddy fields and irrigation systems. Due to its habitat, Climbing perch is exposed to toxic pesticides used in paddy fields such as metaldehyde which is one of the most widely used molluscicide. This study aims to determine the acute toxicity Lethal Concentration50 (LC50) of metaldehyde and its effect on the behaviour and physical changes of the Climbing perch. The fish mortality responses to six different metaldehyde concentrations ranging from 180 to 330 mg/L were investigated. The 96-h LC50 values were determined and analysed using three different analysis methods which is arithmetic, logarithmic and probit graphic. The LC50 values obtained in this study were 239, 234 and 232 mg/L, respectively. After 96-h of exposure to metaldehyde, the fish showed a series of abnormal behavioural response in all cases: imbalance position, and restlessness of movement. The LC50 values show that metaldehyde is moderately toxic to the Climbing perch indicating that metaldehyde is not destructive to Climbing perch. However, long term exposure of aquatic organisms to the metaldehyde means a continuous health risk for the fish population as they are more vulnerable and it is on high risk for human to consume this toxicated fishes.

Enhancing the Trajectory Generation of a Stair-Climbing Mobility System

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Chocoteco, Jose Abel

2017-01-01

Recent advances in mobile robotic technologies have enabled significant progress to be made in the development of Stair-Climbing Mobility Systems (SCMSs) for people with mobility impairments and limitations. These devices are mainly characterized by their ability to negotiate those architectural barriers associated with climbing stairs (curbs, ramps, etc.). The development of advanced trajectory generators with which to surpass such architectural barriers is one of the most important aspects of SCMSs that has not yet been appropriately exploited. These advanced trajectory generators have a considerable influence on the time invested in the stair climbing process and on passenger comfort and, consequently, provide people with physical disabilities with greater independence and a higher quality of life. In this paper, we propose a new nonlinear trajectory generator for an SCMS. This generator balances the stair-climbing time and the user’s comfort and includes the most important constraints inherent to the system behavior: the geometry of the architectural barrier, the reconfigurable nature of the SCMS (discontinuous states), SCMS state-transition diagrams, comfort restrictions and physical limitations as regards the actuators, speed and acceleration. The SCMS was tested on a real two-step staircase using different time-comfort combinations and different climbing strategies to verify the effectiveness and the robustness of the proposed approach.

Performance and scaling of a novel locomotor structure: adhesive capacity of climbing gobiid fishes.

Science.gov (United States)

Maie, Takashi; Schoenfuss, Heiko L; Blob, Richard W

2012-11-15

Many species of gobiid fishes adhere to surfaces using a sucker formed from fusion of the pelvic fins. Juveniles of many amphidromous species use this pelvic sucker to scale waterfalls during migrations to upstream habitats after an oceanic larval phase. However, adults may still use suckers to re-scale waterfalls if displaced. If attachment force is proportional to sucker area and if growth of the sucker is isometric, then increases in the forces that climbing fish must resist might outpace adhesive capacity, causing climbing performance to decline through ontogeny. To test for such trends, we measured pressure differentials and adhesive suction forces generated by the pelvic sucker across wide size ranges in six goby species, including climbing and non-climbing taxa. Suction was achieved via two distinct growth strategies: (1) small suckers with isometric (or negatively allometric) scaling among climbing gobies and (2) large suckers with positively allometric growth in non-climbing gobies. Species using the first strategy show a high baseline of adhesive capacity that may aid climbing performance throughout ontogeny, with pressure differentials and suction forces much greater than expected if adhesion were a passive function of sucker area. In contrast, large suckers possessed by non-climbing species may help compensate for reduced pressure differentials, thereby producing suction sufficient to support body weight. Climbing Sicyopterus species also use oral suckers during climbing waterfalls, and these exhibited scaling patterns similar to those for pelvic suckers. However, oral suction force was considerably lower than that for pelvic suckers, reducing the ability for these fish to attach to substrates by the oral sucker alone.

Ferns: the missing link in shoot evolution and development

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Andrew Robert George Plackett

2015-11-01

Full Text Available Shoot development in land plants is a remarkably complex process that gives rise to an extreme diversity of forms. Our current understanding of shoot developmental mechanisms comes almost entirely from studies of angiosperms (flowering plants, the most recently diverged plant lineage. Shoot development in angiosperms is based around a layered multicellular apical meristem that produces lateral organs and/or secondary meristems from populations of founder cells at its periphery. In contrast, non-seed plant shoots develop from either single apical initials or from a small population of morphologically distinct apical cells. Although developmental and molecular information is becoming available for non-flowering plants, such as the model moss Physcomitrella patens, making valid comparisons between highly divergent lineages is extremely challenging. As sister group to the seed plants, the monilophytes (ferns and relatives represent an excellent phylogenetic midpoint of comparison for unlocking the evolution of shoot developmental mechanisms, and recent technical advances have finally made transgenic analysis possible in the emerging model fern Ceratopteris richardii. This review compares and contrasts our current understanding of shoot development in different land plant lineages with the aim of highlighting the potential role that the fern C. richardii could play in shedding light on the evolution of underlying genetic regulatory mechanisms.

Notes on the scholarly trajectory of Mª. Dolores Fernández-Posse

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Gilman, Antonio

2007-12-01

Full Text Available The scholarly trajectory of Mª Dolores Fernández- Posse involved an ongoing process of critical observation, reflection, and change that is quite rare in Archaeology. Her change from normativism to a historically informed functionalism is representative of the general evolution of Spanish archaeological studies over the course of the past thirty years. What is unusual about Fernández-Posse -and attests to her straightforward and unassuming intelligence- is that she herself changed her mind and voiced that change with clarity and humor.

La trayectoria científica de Mª Dolores Fernández-Posse se caracterizó por un proceso continuo de observación crítica, reflexión y cambio, algo poco común en Arqueología. Su cambio del normativismo a un funcionalismo de orientación histórica es representativo de la evolución de los estudios arqueológicos en España a lo largo de los últimos treinta años. Lo realmente inusual de Fernández-Posse -y lo que atestigua su directa pero no pretenciosa inteligencia- es que ella misma cambió de ideas y publicitó ese cambio con claridad y humor.

Colonisation of epiphytic ferns by skinks and geckos in the high canopy of a Bornean rainforest

OpenAIRE

Donald, J.; Clegg, J.; Ellwood, M. D. F.

2017-01-01

Nest site availability limits the fitness and survival of skinks and geckos, particularly in the canopy of tall tropical rainforests. We document the systematic colonisation and nest use of epiphytic bird’s nest ferns (Asplenium spp) by the gecko Hemiphyllodactylus typus and the skink Lipinia cf. vittigera. As part of a controlled experiment we placed 32 ferns of similar sizes in the high canopy of a lowland dipterocarp rainforest in Sabah, Malaysian Borneo. Half of these ferns, sampled after...

Restoring Native Forest Understory: The Influence of Ferns and Light in a Hawaiian Experiment

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Robert Shallenberger

2013-03-01

Full Text Available Ecological restoration is an increasingly important component of sustainable land management. We explore potential facilitative relationships for enhancing the cost-effectiveness of restoring native forest understory, focusing on two factors: (1 overstory shade and (2 possible facilitation by a fern (Dryopteris wallichiana, one of few native colonists of pasture in our montane Hawaiˈi study system. We planted 720 understory tree seedlings and over 4000 seeds of six species under six planting treatments: a full factorial combination of low, medium and high light, situating plantings in either the presence or absence of a mature fern. After three years, 75% of outplanted seedlings survived. Seedling survivorship was significantly higher in the presence of a fern (79% vs. 71% without a fern and in medium and low light conditions (81% vs. 64% in high light. Relative height was highest at low to medium light levels. After 2.2 years, 2.8% of the planted seeds germinated. We observed no significant differences in seed germination relative to light level or fern presence. Analyzing several approaches, we found nursery germination of seeds followed by outplanting ca. 20% less costly than direct seeding in the field. This study opens new questions about facilitation mechanisms that have the potential to increase the extent and effectiveness of restoration efforts.

Knowledge-Based Estimation of Edible Fern Harvesting Sites in Mountainous Communities of Northeastern Japan

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Toshiya Matsuura

2013-12-01

Full Text Available Once local expert knowledge regarding the harvesting of various non-timber forest products (NTFPs is lost, it is difficult to recover. We investigated whether the knowledge of expert forest harvesters can be used to determine the habitat distribution and harvesting sites of three popular edible wild ferns, i.e., ostrich fern (Matteuccia struthiopteris, bracken (Pteridium aquilinum, and royal fern (Osmunda japonica, in mountainous communities of western Fukushima, Japan. Using multi-criteria evaluation (MCE based on the analytic hierarchy process (AHP and geographic information system (GIS, we found that harvesters were easily able to recognize differences in the spatial characteristics of the habitat distribution of fern species due to both natural and anthropogenic factors. These factors were described by various GIS layers, such as vegetation and terrain features (e.g., gradient, aspect, and slope position derived from a 20-m digital elevation model (DEM. Harvesting sites were limited by their distance from a roadway, which differed among species. By comparison with the GPS records of actual harvesting sites, we estimated the potential harvesting sites of each fern species with reasonable accuracy, particularly for bracken. Our results show that the knowledge of expert forest harvesters can be quantified using MCE and GIS, which is useful for determining the spatial characteristics of NTFP harvesting and ensuring sustainable management practices.

Phylogenetic Relationships of the Fern Cyrtomium falcatum (Dryopteridaceae from Dokdo Island Based on Chloroplast Genome Sequencing

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Gurusamy Raman

2016-12-01

Full Text Available Cyrtomium falcatum is a popular ornamental fern cultivated worldwide. Native to the Korean Peninsula, Japan, and Dokdo Island in the Sea of Japan, it is the only fern present on Dokdo Island. We isolated and characterized the chloroplast (cp genome of C. falcatum, and compared it with those of closely related species. The genes trnV-GAC and trnV-GAU were found to be present within the cp genome of C. falcatum, whereas trnP-GGG and rpl21 were lacking. Moreover, cp genomes of Cyrtomium devexiscapulae and Adiantum capillus-veneris lack trnP-GGG and rpl21, suggesting these are not conserved among angiosperm cp genomes. The deletion of trnR-UCG, trnR-CCG, and trnSeC in the cp genomes of C. falcatum and other eupolypod ferns indicates these genes are restricted to tree ferns, non-core leptosporangiates, and basal ferns. The C. falcatum cp genome also encoded ndhF and rps7, with GUG start codons that were only conserved in polypod ferns, and it shares two significant inversions with other ferns, including a minor inversion of the trnD-GUC region and an approximate 3 kb inversion of the trnG-trnT region. Phylogenetic analyses showed that Equisetum was found to be a sister clade to Psilotales-Ophioglossales with a 100% bootstrap (BS value. The sister relationship between Pteridaceae and eupolypods was also strongly supported by a 100% BS, but Bayesian molecular clock analyses suggested that C. falcatum diversified in the mid-Paleogene period (45.15 ± 4.93 million years ago and might have moved from Eurasia to Dokdo Island.

Valgus-varus motion of the knee in normal level walking and stair climbing.

Science.gov (United States)

Yu, B; Stuart, M J; Kienbacher, T; Growney, E S; An, K-N

1997-07-01

OBJECTIVE: The knee valgus-varus moment and the knee angles were compared between normal level walking and stair climbing. DESIGN: Ten healthy subjects were tested for ascent, descent, and level walking. BACKGROUND: An understanding of the normal valgus-varus motion of the knee during stair climbing is needed to apply biomechanical analysis of stair climbing as a evaluation tool for knee osteoarthritis patients. METHODS: A motion analysis system, three force plates, and a flight of stairs were used to collect kinematic and kinetic data. The knee angles and moments were calculated from the collected kinematic and kinetic data. RESULTS: The knee varus angle for the maximum knee valgus moments in stair climbing was significantly greater than that in level walking. The knee valgus moment was significantly correlated to ground reaction forces and knee valgus-varus angle during stair climbing and level walking. CONCLUSIONS: There is a coupling between the knee valgus-varus motion and flexion-extension motion. Ground reaction forces are the major contributors to the within-subject variation in the knee valgus-varus moment during stair climbing and level walking. The knee valgus-varus angle is a major contributor to the between-subject variation in the knee valgus moment during stair climbing and level walking.

The climb of dissociated dislocations in a quenched Cu-13.43 at.% Al alloy

International Nuclear Information System (INIS)

Decamps, B.; Cherns, D.; Condat, M.

1983-01-01

The weak-beam electron microscopy technique has been used to study the climb of dissociated dislocations in a Cu-13.43 at.% Al alloy under conditions of supersaturation of vacancies introduced by quenching. The results are similar to those obtained under electron irradiation (interstitial climb) in the same alloy (Cherns, Hirsch and Saka 1980) in that climb may proceed by the nucleation of prismatic loops on the individual partials. The nature of the loops is such as to minimize the total energy of the configuration (partial plus loop) and to maximize their edge component. Interaction with the other partial has been observed, causing the entire dislocation to climb. Additional features observed suggest that climb under quenching is initiated by the nucleation of Frank loops. The detailed configurations also enable climb by absorption of vacancies and interstitials to be distinguished. (author)

Amount of balance necessary for the independence of transfer and stair-climbing in stroke inpatients.

Science.gov (United States)

Fujita, Takaaki; Sato, Atsushi; Ohashi, Yuji; Nishiyama, Kazutaka; Ohashi, Takuro; Yamane, Kazuhiro; Yamamoto, Yuichi; Tsuchiya, Kenji; Otsuki, Koji; Tozato, Fusae

2018-05-01

The purpose of this study was to clarify the amount of balance necessary for the independence of transfer and stair-climbing in stroke patients. This study included 111 stroke inpatients. Simple and multiple regression analyses were conducted to establish the association between the FIM ® instrument scores for transfer or stair-climbing and Berg Balance Scale. Furthermore, receiver operating characteristic curves were used to elucidate the amount of balance necessary for the independence of transfer and stair-climbing. Simple and multiple regression analyses showed that the FIM ® instrument scores for transfer and stair-climbing were strongly associated with Berg Balance Scale. On comparison of the independent and supervision-dependent groups, Berg Balance Scale cut-off values for transfer and stair-climbing were 41/40 and 54/53 points, respectively. On comparison of the independent-supervision and dependent groups, the cut-off values for transfer and stair-climbing were 30/29 and 41/40 points, respectively. The calculated cut-off values indicated the amount of balance necessary for the independence of transfer and stair-climbing, with and without supervision, in stroke patients. Berg Balance Scale has a good discriminatory ability and cut-off values are clinically useful to determine the appropriate independence levels of transfer and stair-climbing in hospital wards. Implications for rehabilitation The Berg Balance Scale's (BBS) strong association with transfer and stair-climbing independence and performance indicates that establishing cut-off values is vitally important for the established use of the BBS clinically. The cut-off values calculated herein accurately demonstrate the level of balance necessary for transfer and stair-climbing independence, with and without supervision, in stroke patients. These criteria should be employed clinically for determining the level of independence for transfer and stair-climbing as well as for setting balance training

Tree ferns: monophyletic groups and their relationships as revealed by four protein-coding plastid loci.

Science.gov (United States)

Korall, Petra; Pryer, Kathleen M; Metzgar, Jordan S; Schneider, Harald; Conant, David S

2006-06-01

Tree ferns are a well-established clade within leptosporangiate ferns. Most of the 600 species (in seven families and 13 genera) are arborescent, but considerable morphological variability exists, spanning the giant scaly tree ferns (Cyatheaceae), the low, erect plants (Plagiogyriaceae), and the diminutive endemics of the Guayana Highlands (Hymenophyllopsidaceae). In this study, we investigate phylogenetic relationships within tree ferns based on analyses of four protein-coding, plastid loci (atpA, atpB, rbcL, and rps4). Our results reveal four well-supported clades, with genera of Dicksoniaceae (sensu ) interspersed among them: (A) (Loxomataceae, (Culcita, Plagiogyriaceae)), (B) (Calochlaena, (Dicksonia, Lophosoriaceae)), (C) Cibotium, and (D) Cyatheaceae, with Hymenophyllopsidaceae nested within. How these four groups are related to one other, to Thyrsopteris, or to Metaxyaceae is weakly supported. Our results show that Dicksoniaceae and Cyatheaceae, as currently recognised, are not monophyletic and new circumscriptions for these families are needed.

Unique expression of a sporophytic character on the gametophytes of notholaenid ferns (Pteridaceae).

Science.gov (United States)

Johnson, Anne K; Rothfels, Carl J; Windham, Michael D; Pryer, Kathleen M

2012-06-01

Not all ferns grow in moist, shaded habitats; some lineages thrive in exposed, seasonally dry environments. Notholaenids are a clade of xeric-adapted ferns commonly characterized by the presence of a waxy exudate, called farina, on the undersides of their leaves. Although some other lineages of cheilanthoid ferns also have farinose sporophytes, previous studies suggested that notholaenids are unique in also producing farina on their gametophytes. For this reason, consistent farina expression across life cycle phases has been proposed as a potential synapomorphy for the genus Notholaena. Recent phylogenetic studies have shown two species with nonfarinose sporophytes to be nested within Notholaena, with a third nonfarinose species well supported as sister to all other notholaenids. This finding raises the question: are the gametophytes of these three species farinose like those of their close relatives, or are they glabrous, consistent with their sporophytes? We sowed spores of a diversity of cheilanthoid ferns onto culture media to observe and document whether their gametophytes produced farina. To place these species within a phylogenetic context, we extracted genomic DNA, then amplified and sequenced three plastid loci. The aligned data were analyzed using maximum likelihood to generate a phylogenetic tree. Here we show that notholaenids lacking sporophytic farina also lack farina in the gametophytic phase, and notholaenids with sporophytic farina always display gametophytic farina (with a single exception). Outgroup taxa never displayed gametophytic farina, regardless of whether they displayed farina on their sporophytes. Notholaenids are unique among ferns in consistently expressing farina across both phases of the life cycle.

Beneficial aerodynamic effect of wing scales on the climbing flight of butterflies.

Science.gov (United States)

Slegers, Nathan; Heilman, Michael; Cranford, Jacob; Lang, Amy; Yoder, John; Habegger, Maria Laura

2017-01-30

It is hypothesized that butterfly wing scale geometry and surface patterning may function to improve aerodynamic efficiency. In order to investigate this hypothesis, a method to measure butterfly flapping kinematics optically over long uninhibited flapping sequences was developed. Statistical results for the climbing flight flapping kinematics of 11 butterflies, based on a total of 236 individual flights, both with and without their wing scales, are presented. Results show, that for each of the 11 butterflies, the mean climbing efficiency decreased after scales were removed. Data was reduced to a single set of differences of climbing efficiency using are paired t-test. Results show a mean decrease in climbing efficiency of 32.2% occurred with a 95% confidence interval of 45.6%-18.8%. Similar analysis showed that the flapping amplitude decreased by 7% while the flapping frequency did not show a significant difference. Results provide strong evidence that butterfly wing scale geometry and surface patterning improve butterfly climbing efficiency. The authors hypothesize that the wing scale's effect in measured climbing efficiency may be due to an improved aerodynamic efficiency of the butterfly and could similarly be used on flapping wing micro air vehicles to potentially achieve similar gains in efficiency.

Uptake of rare earth elements by dryopteris erythrosora (autumn fern)

International Nuclear Information System (INIS)

Ozaki, Takuo; Enomoto, Shuichi

2001-01-01

Mechanisms of uptake of rare earth elements (REEs) were investigated, particularly those by REE accumulator species (autumn fern). Rare earth elements are practically insoluble under natural conditions, suggesting some unknown mechanisms in REE accumulator species. In the present investigation, two notable phenomena were observed. (1) Concerning the ionic-radius dependence of REE uptake by leaves, nonaccumulator species showed an extremely high uptake for Y compared with the adjacent-ionic-radius REEs in the multitracer, while accumulator species showed no anomaly. (2) REE uptake by autumn fern was influenced by the addition of chelating chemical reagents in the uptake solution, while no effect was observed for nonaccumulator species. (author)

Research on Dynamics and Stability in the Stairs-climbing of a Tracked Mobile Robot

OpenAIRE

Tao, Weijun; Ou, Yi; Feng, Hutian

2012-01-01

Aiming at the functional requirement of climbing up the stairs, the dynamics and stability during a tracked mobile robot's climbing of stairs is studied. First, from the analysis of its cross-country performance, the mechanical structure of the tracked mobile robot is designed and the hardware composition of its control system is given. Second, based on the analysis to its stairs-climbing process, the dynamical model of stairs-climbing is established by using the classical mechanics method. N...

Global diversification of a tropical plant growth form: environmental correlates and historical contingencies in climbing palms.

Science.gov (United States)

Couvreur, Thomas L P; Kissling, W Daniel; Condamine, Fabien L; Svenning, Jens-Christian; Rowe, Nick P; Baker, William J

2014-01-01

Tropical rain forests (TRF) are the most diverse terrestrial biome on Earth, but the diversification dynamics of their constituent growth forms remain largely unexplored. Climbing plants contribute significantly to species diversity and ecosystem processes in TRF. We investigate the broad-scale patterns and drivers of species richness as well as the diversification history of climbing and non-climbing palms (Arecaceae). We quantify to what extent macroecological diversity patterns are related to contemporary climate, forest canopy height, and paleoclimatic changes. We test whether diversification rates are higher for climbing than non-climbing palms and estimate the origin of the climbing habit. Climbers account for 22% of global palm species diversity, mostly concentrated in Southeast Asia. Global variation in climbing palm species richness can be partly explained by past and present-day climate and rain forest canopy height, but regional differences in residual species richness after accounting for current and past differences in environment suggest a strong role of historical contingencies in climbing palm diversification. Climbing palms show a higher net diversification rate than non-climbers. Diversification analyses of palms detected a diversification rate increase along the branches leading to the most species-rich clade of climbers. Ancestral character reconstructions revealed that the climbing habit originated between early Eocene and Miocene. These results imply that changes from non-climbing to climbing habits may have played an important role in palm diversification, resulting in the origin of one fifth of all palm species. We suggest that, in addition to current climate and paleoclimatic changes after the late Neogene, present-day diversity of climbing palms can be explained by morpho-anatomical innovations, the biogeographic history of Southeast Asia, and/or ecological opportunities due to the diversification of high-stature dipterocarps in Asian TRFs.

Mechanical Design and Dynamcis of an Autonomous Climbing Robot for Elliptic Half-shell Cleaning

Directory of Open Access Journals (Sweden)

Houxiang Zhang

2007-12-01

Full Text Available This paper presents an auto-climbing robot for cleaning the elliptic half-shell of National Grand Theatre in China. The robot consists of a climbing mechanism, a moving mechanism, two cleaning brushes and supporting mechanisms. The mechanism and unique aspects are presented in detail. A distributed control system based on CAN bus is designed to meet the requirements of controlling the robot. After that the emphasis for discussion is on the motion realization which includes climbing and cleaning movements. The robot independently climbs and descends in the vertical direction and cleans in the horizontal direction. It takes the circling tracks as supports for climbing up and down between strips and moving horizontally along one strip around the ellipsoid. For system design and control purposes, the dynamic models of the climbing and cleaning processes are given applying of the Lagrange equation. Furthermore the force distribution of the front and rear supporting mechanisms is computed in a way that ensures the safety of the climbing process. In the end, the successful on-site tests confirm the principles described above and the robot's ability.

Mechanical Design and Dynamcis of an Autonomous Climbing Robot for Elliptic Half-shell Cleaning

Directory of Open Access Journals (Sweden)

Houxiang Zhang

2008-11-01

Full Text Available This paper presents an auto-climbing robot for cleaning the elliptic half-shell of National Grand Theatre in China. The robot consists of a climbing mechanism, a moving mechanism, two cleaning brushes and supporting mechanisms. The mechanism and unique aspects are presented in detail. A distributed control system based on CAN bus is designed to meet the requirements of controlling the robot. After that the emphasis for discussion is on the motion realization which includes climbing and cleaning movements. The robot independently climbs and descends in the vertical direction and cleans in the horizontal direction. It takes the circling tracks as supports for climbing up and down between strips and moving horizontally along one strip around the ellipsoid. For system design and control purposes, the dynamic models of the climbing and cleaning processes are given applying of the Lagrange equation. Furthermore the force distribution of the front and rear supporting mechanisms is computed in a way that ensures the safety of the climbing process. In the end, the successful on-site tests confirm the principles described above and the robot's ability.

A Fuzzy Control Based Stair-Climbing Service Robot

OpenAIRE

Wang, Ming-Shyan

2010-01-01

In the chapter, we have developed a stair-climbing robot to provide service for the elders and completed two walking experiments of moving up and down stairs with the rise/depth of 120/400 mm and 175/280 mm. The third experiment of object tracking, capturing, and loading by the arm have been shown in the taped pictures from videos to verify the proposed design. In fact, we will show the arm may capture the specific object during climbing up and down in the future. In addition, the robot will ...

Fern extracts potentiate fluconazole activity and inhibit morphological changes in Candida species

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Maria A. Freitas

2017-11-01

Conclusions: The extracts obtained from the fern species L. venustum and P. calomelanos dose not present significant antifungal activity. However, P. calomelanos potentiates the activity of fluconazole and both extracts inhibits the morphological changes in Candida species, indicating that they have potential pharmacological activity as modulators of fungal biology. Therefore, novel studies are required to characterize the interference of these extracts in the virulence and pathogenicity of Candida species as well as the potential of fern species to treat fungal infections.

FEEDING ECOLOGY OF TREE-CLIMBING MANGROVE SESARMID CRABS FROM LUZON, PHILIPPINES

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JIMMY TEVAR MASAGCA

2009-01-01

Full Text Available Despite the large ecological study of tree-climbing mangrove sesarmid crabs in other countries, the Philippine representatives appear to have not been investigated extensively. This paper presents the feeding ecology as to dependence on mangrove trees of sesarmids in different mangrove areas of southern Luzon. This is biased on the nature of the crab habitats, arboreal climbing skills and burrowing behavior of the sesarmids: Selatium elongatum and Episesarma versicolor − exclusive mangrove tree climbers (EMTC; Sarmatium germaini − occasional mangrove tree climber (OMTC; and the non-mangrove tree-climbing (NMTC sesarmids- Neosarmatium smithii, Perisesarma bidens and Perisesarma eumolpe

Phototropic leaf movements and photosynthetic performance in an amphibious fern, Marsilea quadrifolia.

Science.gov (United States)

Kao, Wen-Yuan; Lin, Bai-Ling

2010-09-01

Diurnal phototropism has not been reported in ferns. In this study we found that the four leaflets of the amphibious fern Marsilea quadrifolia are capable of adjusting their leaflet angle and leaflet azimuth in response to changes in the position of the sun's direct beam, exhibiting more diaphototropic movements (orienting the plane of the lamina perpendicular to incident light) in the morning and late afternoon, and more paraphototropic movements (orienting the plane of the lamina parallel to incident light) at noon. In addition, by cutting off the leaflet lamina and covering portions of leaflets with black tape, the junction between the leaflet and petiole was found to be responsible for light reception. Among the light spectrum investigated, blue light was the most effective at inducing diaphototropism. The role of diurnal phototropism in enhancing carbon return and ameliorating photoinhibition was also evaluated. It was concluded that diurnal phototropic leaf movement represents one of the plastic responses enabling this amphibious fern to grow under terrestrial conditions.

Jasmonic and salicylic acid response in the fern Azolla filiculoides and its cyanobiont.

Science.gov (United States)

de Vries, Sophie; de Vries, Jan; Teschke, Hendrik; von Dahlen, Janina K; Rose, Laura E; Gould, Sven B

2018-01-03

Plants sense and respond to microbes utilizing a multilayered signalling cascade. In seed plants, the phytohormones jasmonic and salicylic acid (JA and SA) are key denominators of how plants respond to certain microbes. Their interplay is especially well-known for tipping the scales in plants' strategies of dealing with phytopathogens. In non-angiosperm lineages, the interplay is less well understood, but current data indicate that it is intertwined to a lesser extent and the canonical JA/SA antagonism appears to be absent. Here, we used the water fern Azolla filiculoides to gain insights into the fern's JA/SA signalling and the molecular communication with its unique nitrogen fixing cyanobiont Nostoc azollae, which the fern inherits both during sexual and vegetative reproduction. By mining large-scale sequencing data, we demonstrate that Azolla has most of the genetic repertoire to produce and sense JA and SA. Using qRT-PCR on the identified biosynthesis and signalling marker genes, we show that Azolla is responsive to exogenously applied SA. Furthermore, exogenous SA application influenced the abundance and gene expression of Azolla's cyanobiont. Our data provide a framework for JA/SA signalling in ferns and suggest that SA might be involved in Azolla's communication with its vertically inherited cyanobiont. © 2018 John Wiley & Sons Ltd.

Criterion-related validity of self-reported stair climbing in older adults.

Science.gov (United States)

Higueras-Fresnillo, Sara; Esteban-Cornejo, Irene; Gasque, Pablo; Veiga, Oscar L; Martinez-Gomez, David

2018-02-01

Stair climbing is an activity of daily living that might contribute to increase levels of physical activity (PA). To date, there is no study examining the validity of climbing stairs assessed by self-report. The aim of this study was, therefore, to examine the validity of estimated stair climbing from one question included in a common questionnaire compared to a pattern-recognition activity monitor in older adults. A total of 138 older adults (94 women), aged 65-86 years (70.9 ± 4.7 years), from the IMPACT65 + study participated in this validity study. Estimates of stair climbing were obtained from the European Prospective Investigation into Cancer and Nutrition (EPIC) PA questionnaire. An objective assessment of stair climbing was obtained with the Intelligent Device for Energy Expenditure and Activity (IDEEA) monitor. The correlation between both methods to assess stair climbing was fair (ρ = 0.22, p = 0.008 for PA energy expenditure and ρ = 0.26, p = 0.002 for duration). Mean differences between self-report and the IDEEA were 7.96 ± 10.52 vs. 9.88 ± 3.32 METs-min/day for PA energy expenditure, and 0.99 ± 1.32 vs. 1.79 ± 2.02 min/day for duration (both Wilcoxon test p < 0.001). Results from the Bland-Altman analysis indicate that bias between both instruments were -1.91 ± 10.30 METs-min/day and -0.80 ± 1.99 min/day, and corresponding limits of agreement for the two instruments were from 18.27 to -22.10 METs-min/day and from 3.09 to -4.70 min/day, respectively. Our results indicate that self-reported stair climbing has modest validity to accurately rank old age participants, and underestimates both PAEE and its duration, as compared with an objectively measured method.

Stair-climbing capabilities of USU's T3 ODV mobile robot

Science.gov (United States)

Robinson, D. Reed; Wood, Carl G.

2001-09-01

A six-wheeled autonomous omni-directional vehicle (ODV) called T3 has been developed at Utah State University's (USU) Center for Self-Organizing and Intelligent Systems (CSOIS). This paper focuses on T3's ability to climb stairs using its unique configuration of 6 independently driven and steered wheels and active suspension height control. The ability of T3, or any similar vehicle, to climb stairs is greatly dependent on the chassis orientation relative to the stairs. Stability criteria is developed for any vehicle dimensions and orientation, on any staircase. All possible yaw and pitch angles on various staircases are evaluated to find vehicle orientations that will allow T3 to climb with the largest margin of stability. Different controller types are investigated for controlling vertical wheel movement with the objective of keeping all wheels in contact with the stairs, providing smooth load transfer between loaded and unloaded wheels, and maintaining optimum chassis pitch and roll angles. A controller is presented that uses feedback from wheel loading, vertical wheel position, and chassis orientation sensors. The implementation of the controller is described, and T3's stair climbing performance is presented and evaluated.

THE DIVERSITY OF EPIPHYTIC FERN ON THE OIL PALM TREE (Elaeis guineensis Jacq. IN PEKANBARU, RIAU

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Nery Sofiyanti

2015-02-01

Full Text Available Oil palm (Elaeis guineensis is one  main commodity in Riau Province. Morphologically, the trunk of oil palm  has suitable environment for the growth of epiphytic fern, due to its broaden base of petiole that may accumulate organic and anorganic debrish. The objective of this study was to investigate the diversity of epiphytic fern on the oil palm tree. A total of 125 oil palm trees from seven  study sites in Pekanbaru, Riau were observed. The number of epiphytic ferns identified in this study was 16 species belongs to six families.

Permanent Magnetic System Design for the Wall-Climbing Robot

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W. Shen

2006-01-01

Full Text Available This paper presents the design and analysis of the permanent magnetic system for a wall-climbing robot with permanent magnetic tracks. Based on the behaviour of gecko lizards, the architecture of the robot was designed and built, including the structure of the adhesion mechanism, the mechanical architecture and the anti-toppling mechanism. The permanent magnetic adhesion mechanism and the tracked locomotion mechanism were employed in this kind of wall-climbing robot. Through static and dynamic force analysis of the robot under different situations, design requirements for the adhesion mechanism were derived. Two different types of structures were put forward for the permanent magnetic units and are further discussed in this paper. These two types of structures are also analysed in detail. In addition, a finite-element method was used to verify the results of magnetic units. Finally, two wall-climbing robots, equipped with different magnetic systems described previously, are explained and their applications are discussed in this paper.

PIXE study on arsenic accumulation by a fern. Pteris vittata

International Nuclear Information System (INIS)

Yamazaki, H.; Ishii, K.; Matsuyama, S.

2010-01-01

Pteris vittata is a fern reported to be an arsenic hyper-accumulator. To develop the practical application of the fern to a phytoremediation technique, it is necessary to explicate the effective accumulation mechanism. In this study, the arsenic distribution and the elemental correlation in the cellular level were examined in the fronds supplied with arsenate and arsenite separately via xylem vessel using an in-air micro-PIXE system at Tohoku University. The difference in transportation rate between arsenate and arsenite as well as the translocation of elements necessary for plant metabolism was revealed in different tissues of the fronds accumulating arsenic in high concentration. Hence, the in-air micro-PIXE analysis is an effective measure for undertaking phytoremediation research of hyper-accumulator plants. (author)

The effect of nitrogen additions on bracken fern and its insect herbivores at sites with high and low atmospheric pollution

Science.gov (United States)

M.E. Jones; M.E. Fenn; T.D. Paine

2011-01-01

The impact of atmospheric pollution, including nitrogen deposition, on bracken fern herbivores has never been studied. Bracken fern is globally distributed and has a high potential to accumulate nitrogen in plant tissue. We examined the response of bracken fern and its herbivores to N fertilization at a high and low pollution site in forests downwind of Los Angeles,...

Amooty, a stair climbing intelligent maintenance robot

Energy Technology Data Exchange (ETDEWEB)

1985-04-01

Toshiba Corporation and a team from Tokyo University have jointly developed a prototype of a mobile, stair climbing intelligent robot, named Amooty, for inspection and maintenance tasks in nuclear power plants.

New observations and synthesis of paleogene heterosporous water ferns

NARCIS (Netherlands)

Collinson, M.E.; Smith, S.Y.; van Konijnenburg-van Cittert, J.H.A.; Batten, D.J.; Refidaff, C.; Barke, J.; Marone, F.

Premise of research. Reproductive structures of modern genera of heterosporous water ferns (Marsileaceae and Salviniaceae) are widespread and abundant in plant mesofossil assemblages from the Paleogene. For Salviniaceae, whole fertile fossil plants give a good understanding of morphology. These

Ferns are less dependent on passive dilution by cell expansion to coordinate leaf vein and stomatal spacing than angiosperms.

Directory of Open Access Journals (Sweden)

Madeline R Carins Murphy

Full Text Available Producing leaves with closely spaced veins is a key innovation linked to high rates of photosynthesis in angiosperms. A close geometric link between veins and stomata in angiosperms ensures that investment in enhanced venous water transport provides the strongest net carbon return to the plant. This link is underpinned by "passive dilution" via expansion of surrounding cells. However, it is not known whether this 'passive dilution' mechanism is present in plant lineages other than angiosperms and is another key feature of the angiosperms' evolutionary success. Consequently, we sought to determine whether the 'passive dilution' mechanism is; (i exclusive to the angiosperms, (ii a conserved mechanism that evolved in the common ancestor of ferns and angiosperms, or (iii has evolved continuously over time. To do this we first we assessed the plasticity of vein and stomatal density and epidermal cell size in ferns in response to light environment. We then compared the relationships between these traits found among ferns with modelled relationships that assume vein and stomatal density respond passively to epidermal cell expansion, and with those previously observed in angiosperms. Vein density, stomatal density and epidermal cell size were linked in ferns with remarkably similar relationships to those observed in angiosperms, except that fern leaves had fewer veins per stomata. However, plasticity was limited in ferns and stomatal spacing was dependent on active stomatal differentiation as well as passive cell expansion. Thus, ferns (like angiosperms appear to coordinate vein and stomatal density with epidermal cell expansion to some extent to maintain a constant ratio between veins and stomata in the leaf. The different general relationships between vein density and stomatal density in ferns and angiosperms suggests the groups have different optimum balances between the production of vein tissue dedicated to water supply and stomatal tissue for gas

Amooty, a stair climbing intelligent maintenance robot

International Nuclear Information System (INIS)

Anon.

1985-01-01

Toshiba Corporation and a team from Tokyo University have jointly developed a prototype of a mobile, stair climbing intelligent robot, named Amooty, for inspection and maintenance tasks in nuclear power plants. (author)

Effect of pretreatments and processing conditions on anti-nutritional factors in climbing bean flours

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Emmanuel Mugabo

2017-04-01

Full Text Available It is difficult for many Rwandans to utilize climbing bean seeds (Phaseolus vulgaris. L mainly because of longer cooking time (2 hours and the high consumption of basic fuel. Climbing beans also contain anti-nutritional factors such tannins, phytates, trypsin inhibitors and phytohemagglutinins that limit nutrient absorption. One way to solve this problem is to utilize the flour of climbing beans made from different treatments and processing methods. In this study, climbing beans were pre-treated by soaking them in water for 24 hours, soaking in 2% sodium bicarbonate solution and steam blanching for 10 minutes. After that, pre-treated climbing beans were processed into flours by processing methods such as roasting, cooking and germination where anti-nutritional factors were reduced. The pretreatments did not significantly (p>0.05 affect phytates in climbing bean flours but processing conditions significantly (p<0.05 reduced it. Pretreatments and processing conditions significantly (p<0.05 reduced tannin content. The pretreatments followed by different processing conditions significantly (p<0.05 decreased trypsin inhibitors content. The great significant decrease in phytohemagglutinins content was observed in pretreatment followed by different processing methods. All pretreatments and processing conditions effectively decreased anti-nutritional factors at low level. However, pretreatments or untreated followed by germination and roasting were found to be the most and the least effective respectively.  Making flour from germinated climbing bean seeds is a good option for sustainable food processing as it reduces anti-nutritional factors. It is an inexpensive method in terms of time, energy and fuel for Rwandan households, restaurants and industries where climbing bean seeds are integral part of daily meal.

WITHIN-POPULATION GENETIC DIVERSITY OF CLIMBING PLANTS AND TREES IN A TEMPERATE FOREST IN CENTRAL CHILE

OpenAIRE

Torres-Díaz, Cristian; Ruiz, Eduardo; Salgado-Luarte, Cristian; Molina-Montenegro, Marco A; Gianoli, Ernesto

2013-01-01

The climbing habit is a key innovation in angiosperm evolution: climbing plant taxa have greater species richness than their non-climbing sister groups. It is considered that highly diversified clades should show increased among-population genetic differentiation. Less clear is the expected pattern regarding within-population genetic diversity in speciose lineages. We tested the hypothesis of greater within-population genetic diversity in climbing plants compared to trees in a temperate fores...

Does a video displaying a stair climbing model increase stair use in a worksite setting?

Science.gov (United States)

Van Calster, L; Van Hoecke, A-S; Octaef, A; Boen, F

2017-08-01

This study evaluated the effects of improving the visibility of the stairwell and of displaying a video with a stair climbing model on climbing and descending stair use in a worksite setting. Intervention study. Three consecutive one-week intervention phases were implemented: (1) the visibility of the stairs was improved by the attachment of pictograms that indicated the stairwell; (2) a video showing a stair climbing model was sent to the employees by email; and (3) the same video was displayed on a television screen at the point-of-choice (POC) between the stairs and the elevator. The interventions took place in two buildings. The implementation of the interventions varied between these buildings and the sequence was reversed. Improving the visibility of the stairs increased both stair climbing (+6%) and descending stair use (+7%) compared with baseline. Sending the video by email yielded no additional effect on stair use. By contrast, displaying the video at the POC increased stair climbing in both buildings by 12.5% on average. One week after the intervention, the positive effects on stair climbing remained in one of the buildings, but not in the other. These findings suggest that improving the visibility of the stairwell and displaying a stair climbing model on a screen at the POC can result in a short-term increase in both climbing and descending stair use. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Muscle fiber type distribution in climbing Hawaiian gobioid fishes: ontogeny and correlations with locomotor performance.

Science.gov (United States)

Cediel, Roberto A; Blob, Richard W; Schrank, Gordon D; Plourde, Robert C; Schoenfuss, Heiko L

2008-01-01

Three species of Hawaiian amphidromous gobioid fishes are remarkable in their ability to climb waterfalls up to several hundred meters tall. Juvenile Lentipes concolor and Awaous guamensis climb using rapid bursts of axial undulation, whereas juvenile Sicyopterus stimpsoni climb using much slower movements, alternately attaching oral and pelvic sucking disks to the substrate during prolonged bouts of several cycles. Based on these differing climbing styles, we hypothesized that propulsive musculature in juvenile L. concolor and A. guamensis would be dominated by white muscle fibers, whereas S. stimpsoni would exhibit a greater proportion of red muscle fibers than other climbing species. We further predicted that, because adults of these species shift from climbing to burst swimming as their main locomotor behavior, muscle from adult fish of all three species would be dominated by white fibers. To test these hypotheses, we used ATPase assays to evaluate muscle fiber type distribution in Hawaiian climbing gobies for three anatomical regions (midbody, anal, and tail). Axial musculature was dominated by white muscle fibers in juveniles of all three species, but juvenile S. stimpsoni had a significantly greater proportion of red fibers than the other two species. Fiber type proportions of adult fishes did not differ significantly from those of juveniles. Thus, muscle fiber type proportions in juveniles appear to help accommodate differences in locomotor demands among these species, indicating that they overcome the common challenge of waterfall climbing through both diverse behaviors and physiological specializations.

How do Continuous Climb Operations affect the capacity of a Terminal Manoeuvre Area?

Energy Technology Data Exchange (ETDEWEB)

Perez Casan, J.A.

2016-07-01

Continuous climb operations are the following step to optimise departure trajectories with the goals of minimizing fuel consumption and pollutants and noise emissions in the airports neighbourhood, although due to intrinsic nature of these procedures, the integration of these procedures need to develop a new framework for airline operators and air traffic control. Based on the BADA model developed by EUROCONTROL, three activities have been carried out: simulation of several continuous climbs for three aircraft types (Light, Medium and Heavy), analysation of different applied separations throughout the climb from the runway up to cruise level and, as third activity, definition of new separation minima to ensure that the minimum separations are not violated with this new procedures along the climb. In this work are presented the results of modelling three continuous climb type (constant true airspeed, constant climb angle and constant vertical speed) and new time-based separations for most used models in Palma TMA, which will be the case-study scenario. Finally, this theoretical analysis has been applied to a real scenario in Palma de Mallorca TMA in order to compare how the capacity deals with the introduction of this new procedure to standard departures, standard departures are understood as a departure with a level-off at a determined altitude and with the possibility to be affected by any ATC action. First outcomes are promising because capacity, theoretically, would not be grossly diminished, which could initially be expected based on previous studies on continuous descent approaches, although these results should be considered cautiously due to the fact that the model lacks several factors of associated uncertainty for a real climb. (Author)

The role of multiple dopamine receptors in apomorphine and N-n-propylnorapomorphine-induced climbing and hypothermia.

Science.gov (United States)

Moore, N A; Axton, M S

1990-03-20

Apomorphine and N-n-propylnorapomorphine (NPA) were compared for their ability to induce stereotyped cage climbing and hypothermia in mice. Climbing behavior was produced by similar doses of apomorphine and NPA (0.625-2.5 mg/kg s.c.), whereas NPA was 43 times more potent than apomorphine in inducing a hypothermic response. SKF38393 caused a shift to the left in the dose-response curve for NPA-induced climbing, the ED50 changing from 0.98 to 0.014 mg/kg. SKF38393 had no effect on apomorphine-induced climbing behaviour. The climbing response produced by apomorphine was antagonised by both D-1 and D-2 antagonists. Climbing behaviour induced by NPA (2.5 mg/kg) could be antagonised by SCH23390 but not by clebopride, however climbing behaviour induced by a low dose of NPA (0.06 mg/kg) plus SKF38393 could be blocked by both D-1 and D-2 receptor antagonists. The hypothermic responses produced by either apomorphine or NPA could only be reversed by the selective D-2 antagonist, clebopride. These results demonstrate that dopamine agonist-induced stereotyped cage climbing requires both D-1 and D-2 receptor stimulation, whereas the hypothermic response is D-2-mediated. The results also show that it is possible to assess the relative activity of a dopamine agonist at D-1 or D-2 receptors in vivo by comparing the ability of the compound to induce hypothermia and climbing behaviour.

Does perceived steepness deter stair climbing when an alternative is available?

Science.gov (United States)

Eves, Frank F; Thorpe, Susannah K S; Lewis, Amanda; Taylor-Covill, Guy A H

2014-06-01

Perception of hill slant is exaggerated in explicit awareness. Proffitt (Perspectives on Psychological Science 1:110-122, 2006) argued that explicit perception of the slant of a climb allows individuals to plan locomotion in keeping with their available locomotor resources, yet no behavioral evidence supports this contention. Pedestrians in a built environment can often avoid climbing stairs, the man-made equivalent of steep hills, by choosing an adjacent escalator. Stair climbing is avoided more by women, the old, and the overweight than by their comparators. Two studies tested perceived steepness of the stairs as a cue that promotes this avoidance. In the first study, participants estimated the steepness of a staircase in a train station (n = 269). Sex, age, height, and weight were recorded. Women, older individuals, and those who were heavier and shorter reported the staircase as steeper than did their comparison groups. In a follow-up study in a shopping mall, pedestrians were recruited from those who chose the stairs and those who avoided them, with the samples stratified for sex, age, and weight status. Participants (n = 229) estimated the steepness of a life-sized image of the stairs they had just encountered, presented on the wall of a vacant shop in the mall. Pedestrians who avoided stair climbing by choosing the escalator reported the stairs as steeper even when demographic differences were controlled. Perceived steepness may to be a contextual cue that pedestrians use to avoid stair climbing when an alternative is available.

Design and Development of a Step Climbing Wheeled Robot

Directory of Open Access Journals (Sweden)

Srijan BHATTACHARYA

2009-08-01

Full Text Available This paper presents a design of Step Climbing Robot that can move in uneven environment and traverse a slope or staircase. The condition imposed on this new system of robot is that it will move only in linear fashion, which will reduce the demands on the physical complexity of the robot unit. A summary of the current state of research in the field of mobile robots as it relates to robot stair climbing and moving in uneven surfaces. The architecture of the robot is developed and compared with the previous design.

Irradiation creep by climb-enables glide of dislocations resulting from preferred absorption of point defects

Energy Technology Data Exchange (ETDEWEB)

Mansur, L K [Oak Ridge National Lab., TN (USA)

1979-04-01

A mechanism of irradiation creep arising from the climb-enabled glide of dislocations due to stress-induced preferred absorption of radiation-produced point defects is proposed. This creep component is here termed preferred absorption glide, PAG. PAG-creep operates in addition to the previously studied components of creep from climb by stress-induced preferred absorption, (SI) PA-creep, and the climb-enabled glide due to excess absorption of interstitials on dislocations during swelling, I-creep. A formulation of the various climb and climb-enabled glide processes which includes earlier results is presented. PAG-creep is comparable in magnitude to PA-creep in the parameter range of applications. While the PSA-creep rate and the I-creep rate are linear in stress, the PAG-creep rate is quadratic in stress and thus dominates at high stresses.

Nona Fernández's Mapocho: Spirits in a Material Wasteland

Directory of Open Access Journals (Sweden)

Resha S Cardone

2015-01-01

Full Text Available This analysis of Mapocho (2002, a novel by Chilean writer and performer Nona Fernández, explores the significance of the author’s environmentalist representation of Chilean history as the accumulation of spiritual and material contaminants—ghosts and trash—that the victorious from throughout the country’s history have attempted to erase to further various economic and political agendas, particularly the neoliberal model installed during the Pinochet dictatorship. Fernández’s depiction of Chile as an ecological and spiritual wasteland in which the female protagonist (recollects, recycles and reuses the specters and detritus of past conflicts represents the author’s own literary project of advocating for human rights and environmental justice during the Chilean transition while modeling a way to counter the collective amnesia promoted under the newly established democracy.

Rhizospheric metagenome of the terrestrial mangrove fern Acrostichum from Indian Sunderbans

Directory of Open Access Journals (Sweden)

Sayak Ganguli

2017-12-01

Full Text Available This study reports the analyses of the rhizospheric microbiome of the terrestrial mangrove fern Acrostichum aureum Linn. from the Indian Sunderbans. Samples were collected using standard protocols and 16S rRNA gene V3–V4 region amplicon sequencing was performed to identify the microbial communities prevalent in the rhizosphere. A total of 1,931,252 quality checked reads were assembled into 204,818 contigs and were analysed using QIIME to reveal the abundance of Proteobacteria, Acidobacteria and Planctomycetes. The data is available at the NCBI - Sequence Read Archive with accession number: SRX2660456. This is the first report of the rhizospheric microbiome belonging to a fern species.

The effects of therapeutic climbing in patients with chronic low back pain: a randomized controlled study.

Science.gov (United States)

Engbert, Kai; Weber, Michaela

2011-05-15

A randomized controlled study investigated the effects of therapeutic climbing in patients with chronic low back pain. Before and after 4 weeks of training, physical and mental well-being were measured by two questionnaires (36-Item Short Form Health Survey [SF-36]; Hannover Functional Ability Questionnaire for measuring back pain-related disability [FFbH-R]). Therapeutic climbing has been suggested to increase muscular strength and perceived physical and mental well-being. This study focused on the psychological effects of therapeutic climbing and compared it with standard exercise therapy. Therapeutic climbing has become increasingly popular in rehabilitation and its effects on muscular strengthening have been shown. Therapeutic climbing has also been suggested to yield psychological effects such as changes in attentional focus from pain to physical capabilities. To date, no controlled clinical trial has investigated these psychological effects and it is unclear whether therapeutic climbing is comparable or superior to other forms of exercise. Twenty-eight patients with chronic low back pain conducted either a therapeutic climbing or a standard exercise regime. Each program took 4 weeks, including four guided training sessions per week. Before and after the program, patients answered two questionnaires assessing their physical and mental well-being. For the Hannover Functional Ability Questionnaire for measuring back pain-related disability, there was no difference before versus after or between the treatments. For the SF-36, both treatments showed significant improvements in 3/8 subscales of the SF-36. In 2/8 subscales, only the participants of the therapeutic climbing improved and in 1/8 subscales the converse was true. Comparing both groups, significantly larger improvements were found after therapeutic climbing in two subscales of the SF-36: physical functioning and general health perception. The benefits of therapeutic climbing were comparable with those of

Fibrillar Adhesive for Climbing Robots

Science.gov (United States)

Pamess, Aaron; White, Victor E.

2013-01-01

A climbing robot needs to use its adhesive patches over and over again as it scales a slope. Replacing the adhesive at each step is generally impractical. If the adhesive or attachment mechanism cannot be used repeatedly, then the robot must carry an extra load of this adhesive to apply a fresh layer with each move. Common failure modes include tearing, contamination by dirt, plastic deformation of fibers, and damage from loading/ unloading. A gecko-like fibrillar adhesive has been developed that has been shown useful for climbing robots, and may later prove useful for grasping, anchoring, and medical applications. The material consists of a hierarchical fibrillar structure that currently contains two levels, but may be extended to three or four levels in continuing work. The contacting level has tens of thousands of microscopic fibers made from a rubberlike material that bend over and create intimate contact with a surface to achieve maximum van der Waals forces. By maximizing the real area of contact that these fibers make and minimizing the bending energy necessary to achieve that contact, the net amount of adhesion has been improved dramatically.

Reliability and Validity of Finger Strength and Endurance Measurements in Rock Climbing

Science.gov (United States)

Michailov, Michail Lubomirov; Baláš, Jirí; Tanev, Stoyan Kolev; Andonov, Hristo Stoyanov; Kodejška, Jan; Brown, Lee

2018-01-01

Purpose: An advanced system for the assessment of climbing-specific performance was developed and used to: (a) investigate the effect of arm fixation (AF) on construct validity evidence and reliability of climbing-specific finger-strength measurement; (b) assess reliability of finger-strength and endurance measurements; and (c) evaluate the…

Comparative multibody dynamics analysis of falls from playground climbing frames

OpenAIRE

Forero Rueda, Manuel A.; Gilchrist, M. D.

2009-01-01

This paper shows the utility of multibody dynamics in evaluating changes in injury related parameters of the head and lower limbs of children following falls from playground climbing frames. A particular fall case was used as a starting point to analyze the influence of surface properties, posture of the body at impact, and intermediate collisions against the climbing frame before impacting the ground. Simulations were made using the 6-year-old pedestrian MADYMO rigid body model and scaled he...

The colonisation of woodland gaps by ferns and horsetails

NARCIS (Netherlands)

Bremer, P.

2010-01-01

In the Voorsterbos, a planted woodland on a former sea-floor (the Netherlands), artificial gaps within stands of Fagus sylvatica on boulder clay were monitored for five or six years after cutting. Ten fern species and three species of horsetail established in these gaps, with Dryopteris cristata,

Mitigating arsenic contamination in rice plants with an aquatic fern, Marsilea minuta.

Science.gov (United States)

Hassi, Ummehani; Hossain, Md Tawhid; Huq, S M Imamul

2017-10-10

Dangers of arsenic contamination are well known in human civilization. The threat increases when arsenic is accumulated in food and livestock through irrigated crops or animal food. Hence, it is important to mitigate the effects of arsenic as much as possible. This paper discusses a process for reducing the level of arsenic in different parts of rice plants with an aquatic fern, Marsilea minuta L. A pot experiment was done to study the possibility of using Marsilea minuta as a phytoremediator of arsenic. Rice and Marsilea minuta were allowed to grow together in soils. As a control, Marsilea minuta was also cultured alone in the presence and absence of arsenic (applied at 1 mg/L as irrigation water). We did not find any significant change in the growth of rice due to the association of Marsilea minuta, though it showed a reduction of approximately 58.64% arsenic accumulation in the roots of rice grown with the association of fern compared to that grown without fern. We measured a bioaccumulation factor (BF) of > 5.34, indicating that Marsilea minuta could be a good phytoremediator of arsenic in rice fields.

The RiSE climbing robot: body and leg design

Science.gov (United States)

Saunders, A.; Goldman, D. I.; Full, R. J.; Buehler, M.

2006-05-01

The RiSE robot is a biologically inspired, six legged climbing robot, designed for general mobility in scansorial (vertical walls, horizontal ledges, ground level) environments. It exhibits ground reaction forces that are similar to animal climbers and does not rely on suction, magnets or other surface-dependent specializations to achieve adhesion and shear force. We describe RiSE's body and leg design as well as its electromechanical, communications and computational infrastructure. We review design iterations that enable RiSE to climb 90° carpeted, cork covered and (a growing range of) stucco surfaces in the quasi-static regime.

Stair climbing is more detrimental to the cement in hip replacement than walking

NARCIS (Netherlands)

Stolk, J.; Verdonschot, N.J.J.; Huiskes, H.W.J.

2002-01-01

Stair climbing may be detrimental to cemented total hip arthroplasties, because it subjects the reconstruction to high torsional loads. The current study investigated how stair climbing contributes to damage accumulation in the cement around a femoral stem compared with walking, taking into account

Instructions for collecting tree ferns of the family Cyatheaceae

NARCIS (Netherlands)

Holttum, R.E.

1957-01-01

The next monographic study which will be undertaken for the series Pteridophyta of the Flora Malesiana will be devoted to the tree ferns of the Cyatheaceae. In connection with the large size of these plants and the desirability of having more and complete material at our disposal, the following

A Survey of Wall Climbing Robots: Recent Advances and Challenges

Directory of Open Access Journals (Sweden)

Shunsuke Nansai

2016-07-01

Full Text Available In recent decades, skyscrapers, as represented by the Burj Khalifa in Dubai and Shanghai Tower in Shanghai, have been built due to the improvements of construction technologies. Even in such newfangled skyscrapers, the façades are generally cleaned by humans. Wall climbing robots, which are capable of climbing up vertical surfaces, ceilings and roofs, are expected to replace the manual workforce in façade cleaning works, which is both hazardous and laborious work. Such tasks require these robotic platforms to possess high levels of adaptability and flexibility. This paper presents a detailed review of wall climbing robots categorizing them into six distinct classes based on the adhesive mechanism that they use. This paper concludes by expanding beyond adhesive mechanisms by discussing a set of desirable design attributes of an ideal glass façade cleaning robot towards facilitating targeted future research with clear technical goals and well-defined design trade-off boundaries.

Wall Climbing Robot Using Electrostatic Adhesion Force Generated by Flexible Interdigital Electrodes

Directory of Open Access Journals (Sweden)

Rong Liu

2013-01-01

Full Text Available Electrostatic adhesion technology has broad application prospects on wall climbing robots because of its unique characteristics compared with other types of adhesion technologies. A double tracked wall climbing robot based on electrostatic adhesion technology is presented including electrode panel design, mechanical structure design, power supply system design and control system design. A theoretical adhesion model was established and the electrostatic potential and field were expressed by series expansions in terms of solutions of the Laplace function. Based on this model, the electrostatic adhesion force was calculated using the Maxwell stress tensor formulation. Several important factors which may influence the electrostatic adhesion force were analysed and discussed by both FEM simulation and theoretical calculation. In addition, experiments on the adhesion performance of the electrode panel and the climbing performance of the robot on various wall materials were carried out. Both the simulation and experiment results verify the feasibility of electrostatic adhesion technology being applied on wall climbing robots. The theoretical model and calculation method for the electrostatic adhesion force proposed in this paper are also justified.

Footwear in rock climbing: Current practice.

Science.gov (United States)

McHenry, R D; Arnold, G P; Wang, W; Abboud, R J

2015-09-01

Many rock climbers wear ill-fitting and excessively tight footwear during activity. However, there is insufficient evidence of the extent or harms of this practice. To investigate footwear use in rock climbers with a focus on issues surrounding fit. A cross-sectional study with active rock climbers of over one year of experience completing a survey on their activity and footwear. Additionally, the authors quantified foot and shoe lengths and sizes alongside demographic data. Ill-fitting and excessively tight footwear was found in 55 out of 56 rock climbers. Foot pain during activity was also commonplace in 91% of the climbers. A mean size reduction of almost 4 UK shoe sizes was found between the climbers' street shoe size and that of their climbing footwear using a calibrated foot/shoe ruler. There is an unfortunate association of climbers of higher abilities seeking a tighter shoe fit (pfootwear use amongst rock climbers, further investigation may aim to quantify its impact and seek a solution balancing climbing performance while mitigating foot injury. Copyright © 2015 Elsevier Ltd. All rights reserved.

Affordance Realization in Climbing: Learning and Transfer.

Science.gov (United States)

Seifert, Ludovic; Orth, Dominic; Mantel, Bruno; Boulanger, Jérémie; Hérault, Romain; Dicks, Matt

2018-01-01

The aim of this study was to investigate how the affordances of an indoor climbing wall changed for intermediate climbers following a period of practice during which hold orientation was manipulated within a learning and transfer protocol. The learning protocol consisted of four sessions, in which eight climbers randomly ascended three different routes of fixed absolute difficulty (5c on the French scale), as fluently as possible. All three routes were 10.3 m in height and composed of 20 hand-holds at the same locations on an artificial climbing wall; only hold orientations were altered: (i) a horizontal-edge route (H) was designed to afford horizontal hold grasping, (ii) a vertical-edge route (V) afforded vertical hold grasping, and (iii), a double-edge route (D) was designed to afford both horizontal and vertical hold grasping. Five inertial measurement units (IMU) (3D accelerometer, 3D gyroscope, 3D magnetometer) were attached to the hip, feet and forearms to analyze the vertical acceleration and direction (3D unitary vector) of each limb and hip in ambient space during the entire ascent. Segmentation and classification processes supported detection of movement and stationary phases for each IMU. Depending on whether limbs and/or hip were moving, a decision tree distinguished four states of behavior: stationary (absence of limb and hip motion), hold exploration (absence of hip motion but at least one limb in motion), hip movement (hip in motion but absence of limb motion) and global motion (hip in motion and at least one limb in motion). Results showed that with practice, the learners decreased the relative duration of hold exploration, suggesting that they improved affordance perception of hold grasp-ability. The number of performatory movements also decreased as performance increased during learning sessions, confirming that participants' climbing efficacy improved as a function of practice. Last, the results were more marked for the H route, while the D route

Affordance Realization in Climbing: Learning and Transfer

Directory of Open Access Journals (Sweden)

Ludovic Seifert

2018-05-01

Full Text Available The aim of this study was to investigate how the affordances of an indoor climbing wall changed for intermediate climbers following a period of practice during which hold orientation was manipulated within a learning and transfer protocol. The learning protocol consisted of four sessions, in which eight climbers randomly ascended three different routes of fixed absolute difficulty (5c on the French scale, as fluently as possible. All three routes were 10.3 m in height and composed of 20 hand-holds at the same locations on an artificial climbing wall; only hold orientations were altered: (i a horizontal-edge route (H was designed to afford horizontal hold grasping, (ii a vertical-edge route (V afforded vertical hold grasping, and (iii, a double-edge route (D was designed to afford both horizontal and vertical hold grasping. Five inertial measurement units (IMU (3D accelerometer, 3D gyroscope, 3D magnetometer were attached to the hip, feet and forearms to analyze the vertical acceleration and direction (3D unitary vector of each limb and hip in ambient space during the entire ascent. Segmentation and classification processes supported detection of movement and stationary phases for each IMU. Depending on whether limbs and/or hip were moving, a decision tree distinguished four states of behavior: stationary (absence of limb and hip motion, hold exploration (absence of hip motion but at least one limb in motion, hip movement (hip in motion but absence of limb motion and global motion (hip in motion and at least one limb in motion. Results showed that with practice, the learners decreased the relative duration of hold exploration, suggesting that they improved affordance perception of hold grasp-ability. The number of performatory movements also decreased as performance increased during learning sessions, confirming that participants' climbing efficacy improved as a function of practice. Last, the results were more marked for the H route, while the D

Stable Stair Climbing in a Simple Hexapod Robot

National Research Council Canada - National Science Library

Moore, E. Z; Buehler, M

2001-01-01

.... Its ability to traverse highly fractured and unstable terrain has already been documented. In this paper, we describe open loop controllers for our small robot to climb and descend regular stairs...

135 tf climbing crane for the construction of large scale plants

International Nuclear Information System (INIS)

1981-01-01

Development of a larger capacity, wider working radius and higher lift climbing crane was in demand since the large block construction method become common in plant construction. At first, scaling up of the conventional climbing crane was planned. But, it turned out that the deflection at the top of the jib would cause the load to drift at takeoff in crane operation. Therefore, the crane was newly designed to solve the problem. Some of its advantage are as follows. (1) This crane can be used as either a climbing or a nonclimbing type depending on installation locations and objective plants. (2) Accurate and easy operation is achieved because of little deflection at the top of the jib. (3) Efficient crane operation is possible through high speed hoisting and slewing motions in frequent auxiliary hoisting operations. (4) The construction time can be shortened by adopting pin joints between the blocks and by reducing the number of assembling parts at the site. A nonclimbing type crane is now in operation at the nuclear power plant in Kashiwazaki and a climbing type will be in operation at the nuclear power plant in Fukushima this year. The report presents an outline of the specifications, structures and advantages. (author)

Use of rbcL and trnL-F as a two-locus DNA barcode for identification of NW-European ferns: an ecological perspective

NARCIS (Netherlands)

Groot, de G.A.; During, H.J.; Maas, J.W.; Schneider, H.; Erkens, R.H.J.

2011-01-01

Although consensus has now been reached on a general two-locus DNA barcode for land plants, the selected combination of markers (rbcL + matK) is not applicable for ferns at the moment. Yet especially for ferns, DNA barcoding is potentially of great value since fern gametophytes—while playing an

Analysis of Relations between Spatiotemporal Movement Regulation and Performance of Discrete Actions Reveals Functionality in Skilled Climbing.

Science.gov (United States)

Orth, Dominic; Kerr, Graham; Davids, Keith; Seifert, Ludovic

2017-01-01

In this review of research on climbing expertise, we focus on different measures of climbing performance, including spatiotemporal measures related to fluency and activity states (i.e., discrete actions), adopted by climbers for achieving overall performance goals of getting to the end of a route efficiently and safely. Currently, a broad range of variables have been reported, however, many of these fail to capture how climbers adapt to a route whilst climbing. We argue that spatiotemporal measures should be considered concurrently with evaluation of activity states (such as reaching or exploring) in order gain a more comprehensive picture of how climbers successfully adapt to a route. Spatial and temporal movement measures taken at the hip are a traditional means of assessing efficiency of climbing behaviors. More recently, performatory and exploratory actions of the limbs have been used in combination with spatiotemporal indicators, highlighting the influence of limb states on climbing efficiency and skill transfer. However, only a few studies have attempted to combine spatiotemporal and activity state measures taken during route climbing. This review brings together existing approaches for observing climbing skill at performance outcome (i.e., spatiotemporal assessments) and process (i.e., limb activity states) levels of analysis. Skill level is associated with a spatially efficient route progression and lower levels of immobility. However, more difficult hold architecture designs require significantly greater mobility and more complex movement patterning to maintain performance. Different forms of functional, or goal-supportive, movement variability, including active recovery and hold exploration, have been implicated as important adaptations to physiological and environmental dynamics that emerge during the act of climbing. Indeed, recently it has also been shown that, when climbing on new routes, efficient exploration can improve the transfer of skill. This

Screening for Ptaquiloside in Ferns: Using Herbarium Specimens for Qualitative Mapping Purposes.

Science.gov (United States)

Rasmussen, Lars Holm; Pedersen, Henrik AErenlund

2017-11-01

Ptaquiloside (PTA) is a noxious carcinogen found widespread in Bracken (Pteridium sp.) but with scattered and unresolved distribution outside the genus. The carcinogen causes Bovine Enzootic Haematuria among cattle all-over the World and is under suspicion of causing human cancers. To set-up a methodology for large-scale qualitative studies on the distribution of PTA in ferns using already available herbarium specimens as source. PTA and the main degradation product pterosin B (PtB) were quantified in aqueous frond extracts by HPLC-DAD. PTA was quantified after forced reaction into PtB. Optimal reaction conditions were tested using hydrochloric acid, sulphuric acid, trifluoroacetic acid (TFA), acetic acid and temperature as the experimental variables. A pair-wise test for PTA degradation in plant-press were used to explore the effect of this preservation regime. A selection of up to 50 years old Bracken herbarium specimens were tested for PTA and PtB. The methodology was applied on 21 fern species from Denmark. An optimised TFA-based method results in 30.7% higher conversion and a 1:1 reaction between PTA and PtB. Full three-dimensional resolution of the analyte was obtained. Preservation of fronds in a plant press increase formation of PtB. Hence, the method is only suitable for qualitative studies. Presence of PTA and PtB were found in samples up to 50 years old. Among 21 ferns tested, the compounds were only found in Pteridium aquilinum. Herbarium specimens up to 50 years old can be used for explorative risk assessment of ferns using HPLC-DAD for quantification and identification. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

The omnipresent water fern Azolla caroliniana does not contain lignin

NARCIS (Netherlands)

Nierop, K.G.J.; Speelman, E.N.; Leeuw, J.W. de; Reichart, G.-J.

2011-01-01

Several studies have reported the presence of large amounts of lignin in ubiquitously occurring species of the freshwater fern Azolla. Molecular analysis using flash pyrolysis and thermally assisted hydrolysis and methylation shows, however, that neither the leaves nor the roots of Azolla contain

Environmental Fate and Analysis of Ptaquiloside from the Bracken Fern

DEFF Research Database (Denmark)

Clauson-Kaas, Frederik

The naturally occurring phytotoxin ptaquiloside (PTA) has long been known to be both acute toxic and carcinogenic. Contents of more than 1% ptaquiloside on dry weight has been detected in bracken (Pteridium spp.), a fern distributed across the globe in often dense populations. This work focused...... on the fate of PTA in the soil-water system, from where it may leach to drinking water sources. PTA was detected in concentrations up to 2.2 µg/L in natural waters receiving drainage from bracken populations, and was found in both surface and groundwater. It was shown that ptaquiloside leached off bracken...... fronds (the leaves of ferns) in concentrations up to 169 µ/L during rainfall events. Rainfall further determined the concentration in a stream that drained a bracken-covered catchment, suggesting that this is a potent driver of ptaquiloside exposure in the environment. In both pure and natural waters, p...

Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan vicariance and limited transoceanic dispersal

OpenAIRE

Korall, Petra; Pryer, Kathleen

2014-01-01

Aim Scaly tree ferns, Cyatheaceae, are a well-supported group of mostly tree-forming ferns found throughout the tropics, the subtropics and the south-temperate zone. Fossil evidence shows that the lineage originated in the Late Jurassic period. We reconstructed large-scale historical biogeographical patterns of Cyatheaceae and tested the hypothesis that some of the observed distribution patterns are in fact compatible, in time and space, with a vicariance scenario related to the break-up of G...

A multistage controlled intervention to increase stair climbing at work: effectiveness and process evaluation.

Science.gov (United States)

Bellicha, Alice; Kieusseian, Aurélie; Fontvieille, Anne-Marie; Tataranni, Antonio; Copin, Nane; Charreire, Hélène; Oppert, Jean-Michel

2016-04-11

Stair climbing helps to accumulate short bouts of physical activity throughout the day as a strategy for attaining recommended physical activity levels. There exists a need for effective long-term stair-climbing interventions that can be transferred to various worksite settings. The aims of this study were: 1) to evaluate short- and long-term effectiveness of a worksite stair-climbing intervention using an objective measurement of stair climbing and a controlled design; and 2) to perform a process evaluation of the intervention. We performed a controlled before-and-after study. The study was conducted in two corporate buildings of the same company located in Paris (France), between September, 2013 and September, 2014. The status of either "intervention site" or "control site" was assigned by the investigators. Participants were on-site employees (intervention site: n = 783; control site: n = 545 at baseline). Two one-month intervention phases using signs (intervention phase 1) and enhancement of stairwell aesthetics (intervention phase 2) were performed. The main outcome was the change in stair climbing, measured with automatic counters and expressed in absolute counts/day/100 employees and percent change compared to baseline. Qualitative outcomes were used to describe the intervention process. Stair climbing significantly increased at the intervention site (+18.7%) but decreased at the control site (-13.3%) during the second intervention phase (difference between sites: +4.6 counts/day/100 employees, p levels at the intervention site, but a significant difference between sites was found (intervention site vs. control site: +2.9 counts/day/100 employees, p level after the end of the study. This study shows a successful stair-climbing intervention at the worksite. The main barriers to adoption and implementation were related to location and visibility of posters. Process evaluation was useful in identifying these barriers throughout the study, and in

Neoendemism in Madagascan scaly tree ferns results from recent, coincident diversification bursts.

Science.gov (United States)

Janssen, Thomas; Bystriakova, Nadia; Rakotondrainibe, France; Coomes, David; Labat, Jean-Noël; Schneider, Harald

2008-08-01

More than 80% of Madagascar's 12,000 plant species are endemic with the degree of endemism reaching as much as 95% in the scaly tree ferns, an important species rich component of Madagascar's evergreen rainforests. Predominantly African or Asian ancestry and divergence times usually postdating the separation of Madagascar from the Gondwanan landmasses have been demonstrated for several Madagascan animal and angiosperm groups. However, evolutionary studies of rainforest-specific lineages are scarce and the ecological context of radiation events has rarely been investigated. Here, we examine the evolution of Madagascan tree ferns as a rainforest-specific model family, integrate results from bioclimatic niche analysis with a dated phylogenetic framework, and propose an evolutionary scenario casting new light on our knowledge of the evolution of large island endemic clades. We show that Madagascar's extant tree fern diversity springs from three distinct ancestors independently colonizing Madagascar in the Miocene and that these three monophyletic clades diversified in three coincident radiation bursts during the Pliocene, reaching exceptionally high diversification rates and most likely responding to a common climatic trigger. Recent diversification bursts may thus have played a major role in the evolution of the extant Madagascan rainforest biome, which hence contains a significant number of young, neoendemic taxa.

Effect of sunflower climbing bean intercroping system on insect pest incidence and crop productivity

International Nuclear Information System (INIS)

Tuey, R.K.; Koros, I.; Wanyonyi, W.

2001-01-01

Intercropping of sunflower and climping beans were evaluated for pest incidence and yield advantages during the main season of 2000/2001 at KARI-NPBRC, Njoro. Three sunflower varieties, Fedha, Record, PAN-7553 and three climbing beans varieties, Puebla, Omukingi and Flora were laid out in a complete randomised block design with four replications. Sunflower was spaced at 75 x 30 cm while the climbing beans were spaced at 50 x 37.5 cm. Assessment of pest damage on various treatments commenced 17 days after planting. Results showed that low plant germination was mainly a result of dry weather and taht cutworm damage was insignificant. There was a sunflower x climbing bean variety interaction, which regulated the aphid infestation of the climbing beans. Sunflower variety PAN-7553 recorded significantly (P<0.01) more pecked heads than the other two varieties. (author)

Design and Implementation of Autonomous Stair Climbing with Nao Humanoid Robot

OpenAIRE

Lu, Wei

2015-01-01

With the development of humanoid robots, autonomous stair climbing is an important capability. Humanoid robots will play an important role in helping people tackle some basic problems in the future. The main contribution of this thesis is that the NAO humanoid robot can climb the spiral staircase autonomously. In the vision module, the algorithm of image filtering and detecting the contours of the stair contributes to calculating the location of the stairs accurately. Additionally, the st...

On the static structural design of climbing robots: part 1.

Science.gov (United States)

Ahmed, Ausama Hadi; Menon, Carlo

This manuscript is the first of two parts of a work investigating optimal configurations of legged climbing robots while loitering on vertical surfaces. In this part 1, a mathematical model of a climbing robot based on the finite element method (FEM), specifically the stiffness method, is generated. A number of parameters, namely the height of the robot, the length of its body and the position of its legs, are investigated to assess their effect on the adhesion requirements needed for the robot to stay attached to a wall. Predictions of the developed mathematical model are validated using FEM commercial software. The body and the legs are assumed to be perpendicular to each other in this part 1. The effect of their inclination is investigated in the subsequent part 2 of our work. In part 2, the model is also used to predict postures that ants have while standing on vertical surfaces. The model is validated by comparing the predicted results to images of loitering ants. The parameters investigated provide guidelines to design legged climbing robots.

Different slopes of a mountain can determine the structure of ferns and lycophytes communities in a tropical forest of Brazil

Directory of Open Access Journals (Sweden)

FELIPE C. NETTESHEIM

2014-03-01

Full Text Available A community of Ferns and Lycophytes was investigated by comparing the occurrence of species on different slopes of a paleoisland in Southeastern Brazil. Our goal was to evaluate the hypothesis that slopes with different geographic orientations determine a differentiation of Atlantic Forest ferns and lycophytes community. We recorded these plants at slopes turned towards the continent and at slopes turned towards the open sea. Analysis consisted of a preliminary assessment on fern beta diversity, a Non Metric Multidimensional Scaling (NMDS and a Student t-test to confirm if sites sampling units ordination was different at each axis. We further used the Pearson coefficient to relate fern species to the differentiation pattern and again Student's t-test to determine if richness, plant cover and abundance varied between the two sites. There was a relatively low number of shared species between the two sites and ferns and lycophytes community variation was confirmed. Some species were detected as indicators of the community variation but we were unable to detect richness, plant cover or abundance differences. Despite the evidence of this variation between the slopes, further works are needed to evaluate which processes are contributing to determine this pattern.

Comparative multibody dynamics analysis of falls from playground climbing frames.

Science.gov (United States)

Forero Rueda, M A; Gilchrist, M D

2009-10-30

This paper shows the utility of multibody dynamics in evaluating changes in injury related parameters of the head and lower limbs of children following falls from playground climbing frames. A particular fall case was used as a starting point to analyze the influence of surface properties, posture of the body at impact, and intermediate collisions against the climbing frame before impacting the ground. Simulations were made using the 6-year-old pedestrian MADYMO rigid body model and scaled head contact characteristics. Energy absorbing surfaces were shown to reduce injury severity parameters by up to 30-80% of those of rigid surfaces, depending on impact posture and surface. Collisions against components of a climbing frame during a fall can increase injury severity of the final impact of the head with the ground by more than 90%. Negligible changes are associated with lower limb injury risks when different surfacing materials are used. Computer reconstructions of actual falls that are intended to quantify the severity of physical injuries rely on accurate knowledge of initial conditions prior to falling, intermediate kinematics of the fall and the orientation of the body when it impacts against the ground. Multibody modelling proved to be a valuable tool to analyze the quality of eyewitness information and analyze the relative injury risk associated with changes in components influencing fall injuries from playground climbing frames. Such simulations can also support forensic investigations by evaluating alternative hypotheses for the sequence of kinematic motion of falls which result in known injuries.

Analysis of Relations between Spatiotemporal Movement Regulation and Performance of Discrete Actions Reveals Functionality in Skilled Climbing

Directory of Open Access Journals (Sweden)

Dominic Orth

2017-10-01

Full Text Available In this review of research on climbing expertise, we focus on different measures of climbing performance, including spatiotemporal measures related to fluency and activity states (i.e., discrete actions, adopted by climbers for achieving overall performance goals of getting to the end of a route efficiently and safely. Currently, a broad range of variables have been reported, however, many of these fail to capture how climbers adapt to a route whilst climbing. We argue that spatiotemporal measures should be considered concurrently with evaluation of activity states (such as reaching or exploring in order gain a more comprehensive picture of how climbers successfully adapt to a route. Spatial and temporal movement measures taken at the hip are a traditional means of assessing efficiency of climbing behaviors. More recently, performatory and exploratory actions of the limbs have been used in combination with spatiotemporal indicators, highlighting the influence of limb states on climbing efficiency and skill transfer. However, only a few studies have attempted to combine spatiotemporal and activity state measures taken during route climbing. This review brings together existing approaches for observing climbing skill at performance outcome (i.e., spatiotemporal assessments and process (i.e., limb activity states levels of analysis. Skill level is associated with a spatially efficient route progression and lower levels of immobility. However, more difficult hold architecture designs require significantly greater mobility and more complex movement patterning to maintain performance. Different forms of functional, or goal-supportive, movement variability, including active recovery and hold exploration, have been implicated as important adaptations to physiological and environmental dynamics that emerge during the act of climbing. Indeed, recently it has also been shown that, when climbing on new routes, efficient exploration can improve the transfer

Is there foul play in the leaf pocket? The metagenome of floating fern Azolla reveals endophytes that do not fix N2 but may denitrify.

Science.gov (United States)

Dijkhuizen, Laura W; Brouwer, Paul; Bolhuis, Henk; Reichart, Gert-Jan; Koppers, Nils; Huettel, Bruno; Bolger, Anthony M; Li, Fay-Wei; Cheng, Shifeng; Liu, Xin; Wong, Gane Ka-Shu; Pryer, Kathleen; Weber, Andreas; Bräutigam, Andrea; Schluepmann, Henriette

2018-01-01

Dinitrogen fixation by Nostoc azollae residing in specialized leaf pockets supports prolific growth of the floating fern Azolla filiculoides. To evaluate contributions by further microorganisms, the A. filiculoides microbiome and nitrogen metabolism in bacteria persistently associated with Azolla ferns were characterized. A metagenomic approach was taken complemented by detection of N 2 O released and nitrogen isotope determinations of fern biomass. Ribosomal RNA genes in sequenced DNA of natural ferns, their enriched leaf pockets and water filtrate from the surrounding ditch established that bacteria of A. filiculoides differed entirely from surrounding water and revealed species of the order Rhizobiales. Analyses of seven cultivated Azolla species confirmed persistent association with Rhizobiales. Two distinct nearly full-length Rhizobiales genomes were identified in leaf-pocket-enriched samples from ditch grown A. filiculoides. Their annotation revealed genes for denitrification but not N 2 -fixation. 15 N 2 incorporation was active in ferns with N. azollae but not in ferns without. N 2 O was not detectably released from surface-sterilized ferns with the Rhizobiales. N 2 -fixing N. azollae, we conclude, dominated the microbiome of Azolla ferns. The persistent but less abundant heterotrophic Rhizobiales bacteria possibly contributed to lowering O 2 levels in leaf pockets but did not release detectable amounts of the strong greenhouse gas N 2 O. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Development of Vmax III. Magnetic wall climbing robot with holonomic and omni-directional mobility

International Nuclear Information System (INIS)

Tsuru, Kiyoshi; Hirose, Shigeo

2012-01-01

Wall-climbing robots having holonomic and omni-directional mobility would enhance the manipulation performance of the mounted arm and enable it to execute various tasks on the surface of large structures. This study focuses on the wall-climbing robots having permanent magnet attractive units to stick to the surface of iron structure such as atomic reactors and discuss the development of a specific holonomic and omni-directional wall-climbing mechanisms. Basic driving mechanism of the wall-climbing robot is based on our former invention named Omni Disk which consists of multiple rollers attached to one side of a rotating disk and having a mechanism to direct the rollers to the same direction. We firstly discuss about the mechanical improvements of the Omni Disk to make it lightweight and low cost. We next discusses about four types of methods to attach permanent magnets to the wall-climbing robot and generates attractive force on the iron wall and select the best type based on the motion experiments about the constructed models. As the result of these considerations, we developed a holonomic and omni-directional wall-climbing robot named Vmax III which consists of three Omni Disks having permanent magnet at their center having the function to change the magnetic attractive force. By using the Vmax III, we studied about the relation among the magnetic attractive force of three Omni Disks, posture of the Vmax III and inclination angle of the iron wall and clarified the optimized distribution of the magnetic attractive force of the Omni Disks in different inclination of the iron wall. (author)

Specific effects of a calorie-based intervention on stair climbing in overweight commuters.

Science.gov (United States)

Lewis, Amanda L; Eves, Frank F

2011-10-01

Point-of-choice prompts consistently increase stair climbing; a greater increase in overweight than normal weight individuals was reported in a multi-component worksite campaign. The purpose of this study is to investigate effects of a multi-component campaign, on stair climbing, in a public access setting. In an interrupted-time-series-design, baseline observations (2 weeks) preceded a 2-week point-of-choice prompt. An additional message, positioned at the top of the climb for a further 6-week period, summarised the calorific consequences of a single ascent. Inconspicuous observers recorded traveller's methods of ascent, coded by sex and weight status, twice a week between 08:00 and 09:59. At baseline, the overweight chose stairs less than normal weight individuals. The multi-component campaign targeting weight control reversed this bias, increasing stair climbing only in overweight individuals. The specificity of the effect confirms the appeal of this lifestyle activity for the overweight. The discussion focuses on how intentions to control weight may be converted into behaviour.

The fossil Osmundales (Royal Ferns)—a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes

OpenAIRE

Benjamin Bomfleur; Guido W. Grimm; Stephen McLoughlin

2017-01-01

The Osmundales (Royal Fern order) originated in the late Paleozoic and is the most ancient surviving lineage of leptosporangiate ferns. In contrast to its low diversity today (less than 20 species in six genera), it has the richest fossil record of any extant group of ferns. The structurally preserved trunks and rhizomes alone are referable to more than 100 fossil species that are classified in up to 20 genera, four subfamilies, and two families. This diverse fossil record constitutes an exce...

Genome size evolution in Ontario ferns (Polypodiidae): evolutionary correlations with cell size, spore size, and habitat type and an absence of genome downsizing.

Science.gov (United States)

Henry, Thomas A; Bainard, Jillian D; Newmaster, Steven G

2014-10-01

Genome size is known to correlate with a number of traits in angiosperms, but less is known about the phenotypic correlates of genome size in ferns. We explored genome size variation in relation to a suite of morphological and ecological traits in ferns. Thirty-six fern taxa were collected from wild populations in Ontario, Canada. 2C DNA content was measured using flow cytometry. We tested for genome downsizing following polyploidy using a phylogenetic comparative analysis to explore the correlation between 1Cx DNA content and ploidy. There was no compelling evidence for the occurrence of widespread genome downsizing during the evolution of Ontario ferns. The relationship between genome size and 11 morphological and ecological traits was explored using a phylogenetic principal component regression analysis. Genome size was found to be significantly associated with cell size, spore size, spore type, and habitat type. These results are timely as past and recent studies have found conflicting support for the association between ploidy/genome size and spore size in fern polyploid complexes; this study represents the first comparative analysis of the trend across a broad taxonomic group of ferns.

Climbing ripple structure and associated storm-lamination from a ...

Indian Academy of Sciences (India)

Pranhita–Godavari Valley, south India, displays well developed climbing ripple lamination and ... sedimentary environments, such as river flood .... Sediment, sequence and facies ..... tic Archaean Witwatersrand Supergroup, South Africa;.

New fern records for Kilimanjaro | Hemp | Journal of East African ...

African Journals Online (AJOL)

Working on the flora and vegetation of Mt Kilimanjaro, Tanzania, 17 ferns in 10 families were found that had not yet been recorded for the floral region T2. The altitudinal range, localities and habitat description are given for Adiantum raddianum, Asplenium bugoiense, Blechnum ivohibense, Blotiella stipitata, Dryopteris ...

The physiological resilience of fern sporophytes and gametophytes: advances in water relations offer new insights into an old lineage

Directory of Open Access Journals (Sweden)

Jarmila ePittermann

2013-08-01

Full Text Available Ferns are some of the oldest vascular plants in existence and they are the second most diverse lineage of tracheophytes next to angiosperms. Recent efforts to understand fern success have fo-cused on the physiological capacity and stress tolerance of both the sporophyte and the gameto-phyte generations. In this review, we examine these insights through the lens of plant water rela-tions, focusing primarily on the form and function of xylem tissue in the sporophyte, as well as the tolerance to and recovery from drought and desiccation stress in both stages of the fern life cycle. The absence of secondary xylem in ferns is compensated by selection for efficient primary xylem composed of large, closely arranged tracheids with permeable pit membranes. Protection from drought-induced hydraulic failure appears to arise from a combination of pit membrane traits and the arrangement of vascular bundles. Features such as tracheid-based xylem and vari-ously sized megaphylls are shared between ferns and more derived lineages, and offer an oppor-tunity to compare convergent and divergent hydraulic strategies critical to the success of xylem-bearing plants. Fern gametophytes show a high degree of desiccation tolerance but new evidence shows that morphological attributes in the gametophytes may facilitate water retention, though little work has addressed the ecological significance of this variation. We conclude with an emergent hypothesis that selection acted on the physiology of both the sporophyte and gameto-phyte generations in a synchronous manner that is consistent with selection for drought tolerance in the epiphytic niche, and the increasingly diverse habitats of the mid to late Cenozoic.

Climbing Mont Blanc and Scalability

OpenAIRE

Chavez, Christian

2016-01-01

This thesis details a proposed system implementation upgrade for the CMB system, accessible at \\url{climb.idi.ntnu.no}, which profiles C/C++ code for its energy efficiency on an Odroid-XU3 board, which utilises a Samsung Exynos 5 Octa CPU, and has an ARM Mali-T628 GPU. Our proposed system implementation improves the robustness of the code base and its execution, in addition to permitting an increased throughput of submissions profiled by the system with the implementation's dispatcher whic...

Effects of sports climbing on muscle performance and balance for patients with multiple sclerosis

DEFF Research Database (Denmark)

Jolk, Christoph; Dalgas, Ulrik; Osada, Nani

2015-01-01

Background/Aims: The potential benefits of sports climbing for many diseases have not been investigated. The aim of this case series was to examine whether sports climbing is feasible and whether it can influence isometric muscle performance and balance in people with multiple sclerosis (MS). Met...

Climbing the health learning curve together | IDRC - International ...

International Development Research Centre (IDRC) Digital Library (Canada)

2011-01-25

Jan 25, 2011 ... Climbing the health learning curve together ... Many of the projects are creating master's programs at their host universities ... Formerly based in the high Arctic, Atlantis is described by Dr Martin Forde of St George's University ...

Agronomic description of new improved climbing bean varieties

African Journals Online (AJOL)

. 21. David, S and Hoogendijk,M. 1997. Bean production systems in MbaJe district, Uganda with emphasis on varietal diversity and the adoption of new climbing beans. Network on bean research in Africa. CIA T. CIA T, occasional publication ...

First megafossil evidence of Cyatheaceous tree fern from the Indian

Indian Academy of Sciences (India)

A part of the compressed tree fern axis with leaf and adventitious root scars in unusual arrangement from Plio–Pleistocene sediments of Arunachal Pradesh, India is described as Cyathea siwalika sp. nov. This record suggests that Cyathea was an important component of tropical evergreen forest in the area during the ...

Analysis of sociodemographic, sport and psychological profile in a rock-climbing experience on university students

Directory of Open Access Journals (Sweden)

Pablo Morilla Portela

2013-07-01

Full Text Available The relationships among several psychological factors in rock climbing was proved a long time ago, nevertheless, most researches are limited to very artificial situations, far away from nature. There are few studies which have carried out this kind of investigation in the natural environment and have combined data collection with real rock climbing practice. The instruments used for this data collection were two questionnaires: CSAI-2 and another one specifically designed to gather the necessary information about sociodemographic characteristic and sport habits. In our work we have studied various individuals’ features (sociodemographic, general sport and outdoor profiles and we have confirmed how they are interrelated and their influence on several psychological factors (cognitive anxiety, somatic anxiety and self-confidence. Through this article we show that there are higher percentages of women than men participants who climb IV-V grade, whereas in higher grades the percentages equalize. Regarding psychological factors, we can notice how on the one hand those participants who climb higher grades and are more interested in rock climbing, feel lower cognitive anxiety and somatic anxiety, while on the other hand they feel higher self-confidence levels

Climbing for preventing and treating health problems: a systematic review of randomized controlled trials

Directory of Open Access Journals (Sweden)

Fechtelpeter, Dennis

2011-01-01

Full Text Available Objective: To summarize the best available evidence on effectiveness of therapeutic or sport climbing in preventing or treating health problems. Methods: We searched Medline, Embase, CENTRAL, PsycINFO, PEDro, OTseeker and SportDiscus for randomized controlled trials published up to December 26, 2010. We included all trials assessing patient-relevant outcomes. Two reviewers independently selected relevant studies, assessed their methodological quality and extracted data. Quality of evidence was rated using the GRADE system. Data were entered into RevMan 5 to calculate effect sizes and 95% confidence intervals where appropriate.Results: Eligible for inclusion were four RCTs studying the effectiveness of climbing in (a geriatric patients, (b adults with multiple sclerosis, (c adults with chronic low-back pain and (d children with disabilities and poor motor function. The sample sizes ranged between 20 and 95. All trials had major methodological limitations. We found very low quality evidence that therapeutic climbing may improve activities of daily living in geriatric patients compared to physiotherapy as measured by the Barthel index (difference in mean change score: 2.32 [95%-CI: 0.45 to 4.19]. We found very low quality evidence that therapeutic climbing compared to standard exercise therapy may improve physical functioning (difference in mean change score: 16.15 [95%-CI: 4.45 to 27.85] and general physical health (13.14 [95%-CI: 3.61 to 22.67] as measured by the SF-36 in adults with chronic low back-pain. Conclusions: Evidence for the effectiveness of therapeutic climbing is limited to small trials at high risk of bias. The effects of therapeutic climbing are therefore unclear.

The accumulation and subcellular distribution of arsenic and antimony in four fern plants.

Science.gov (United States)

Feng, R; Wang, X; Wei, C; Tu, S

2015-01-01

In the present study, Pteris cretica 'Albo-Lineata' (PC), Pteris fauriei (PF), Humata tyermanii Moore (HT), and Pteris ensiformis Burm (PE), were selected to explore additional plant materials for the phytoremediation of As and Sb co-contamination. To some extent, the addition of As and Sb enhanced the growth of HT, PE, and PF. Conversely, the addition of As and Sb negatively affected the growth of PC and was accompanied with the accumulation of high levels of As and Sb in the roots. The highest concentration of Sb was recorded as 6405 mg kg(-1) in the roots of PC, and that for As was 337 mg kg(-1) in the rhizome of PF. To some degree, As and Sb stimulated the uptake of each other in these ferns. Arsenic was mainly stored in the cytoplasmic supernatant (CS) fraction, followed by the cell wall (CW) fraction. In contrast, Sb was mainly found in the CW fraction and, to a lesser extent, in the CS fraction, suggesting that the cell wall and cytosol play different roles in As and Sb accumulation by fern plants. This study demonstrated that these fern plants show a good application potential in the phytoremediation of As and Sb co-contaminated environments.

Response of nitrogen-fixing water fern Azolla biofertilization to rice crop.

Science.gov (United States)

Bhuvaneshwari, K; Singh, Pawan Kumar

2015-08-01

The water fern Azolla harbors nitrogen-fixing cyanobacterium Anabaena azollae as symbiont in its dorsal leaves and is known as potent N 2 fixer. Present investigation was carried out to study the influence of fresh Azolla when used as basal incorporation in soil and as dual cropped with rice variety Mahsoori separately and together with and without chemical nitrogen fertilizer in pots kept under net house conditions. Results showed that use of Azolla as basal or dual or basal plus dual influenced the rice crop positively where use of fern as basal plus dual was superior and served the nitrogen requirement of rice. There was marked increase in plant height, number of effective tillers, dry mass and nitrogen content of rice plants with the use of Azolla and N-fertilizers alone and other combinations. The use of Azolla also increased organic matter and potassium contents of the soil.

Three new fern records for Kilimanjaro | Hemp | Journal of East ...

African Journals Online (AJOL)

Working on the flora and vegetation of Mt. Kilimanjaro, Tanzania, three ferns in three families were found that are not yet recorded for the floral region T2. The altitudinal range, localities and habitat description are given for Adiantum reniforme, Azolla africana and Trichomanes radicans. Journal of East African Natural History ...

Step-Climbing Power Wheelchairs: A Literature Review

Science.gov (United States)

Sundaram, S. Andrea; Wang, Hongwu; Ding, Dan

2017-01-01

Background: Power wheelchairs capable of overcoming environmental barriers, such as uneven terrain, curbs, or stairs, have been under development for more than a decade. Method: We conducted a systematic review of the scientific and engineering literature to identify these devices, and we provide brief descriptions of the mechanism and method of operation for each. We also present data comparing their capabilities in terms of step climbing and standard wheelchair functions. Results: We found that all the devices presented allow for traversal of obstacles that cannot be accomplished with traditional power wheelchairs, but the slow speeds and small wheel diameters of some designs make them only moderately effective in the basic area of efficient transport over level ground and the size and configuration of some others limit maneuverability in tight spaces. Conclusion: We propose that safety and performance test methods more comprehensive than the International Organization for Standards (ISO) testing protocols be developed for measuring the capabilities of advanced wheelchairs with step-climbing and other environment-negotiating features to allow comparison of their clinical effectiveness. PMID:29339886

The Enrichment and Transfer of Heavy Metals for Two Ferns in Pb-Zn Tailing

Directory of Open Access Journals (Sweden)

Mai Jiajie

2017-01-01

Full Text Available The enrichment and transfer of 8 heavy metals of Equisetum ramosissimum and Pteris vittata growing naturally close to edge of the sewage pool in Bencun Pb-Zn Tailing, Eastern Guangdong were investigated. The results indicated that the pollution of Cd, Pb, Hg, Zn was very severe in this tailing, followed by Cu and Mn. The potential ecological risk of heavy metals was assessed to be very strong based on soil background values of Guangdong Province and at high risk according to criteria of the second grade State Soil Environmental Quality Standard, and Cd, Hg, Pb were the main factors leading to potential ecological risk. The content of 8 heavy metals in the two ferns did not reach critical content of hyperaccumulator, so neither of them was typical hyperaccumulator, but both had a certain tolerance to these heavy metal pollution. Underground parts of Pteris vittata had an enrichment coefficient above 1 and that of Equisetum ramosissimum had a value near 1, therefore the two ferns could be utilized as potential enrichment plants. The two ferns have strong adaptability to the tailing habitat and can be used as pioneers in ecological restoration of Pb-Zn tailings.

Phyto-toxicity and Phyto-remediation Potential of Mercury in Indian Mustard and Two Ferns with Mercury Contaminated Water and Oak Ridge Soil

International Nuclear Information System (INIS)

Su, Y.; Han, F.X.; Chen, J.; Shiyab, S.; Monts, D.L.; Monts, D.L.

2009-01-01

Phyto-remediation is an emerging technology that uses various plants to degrade, extract, contain, or immobilize contaminants from soil and water. Certain fern and Indian mustard species have been suggested as candidates for phyto-remediation of heavy metal-contaminated soil and water because of their high efficiency of accumulating metals in shoots and their high biomass production. Currently, no known hyper-accumulator plants for mercury have been found. Here we report the Hg uptake and phyto-toxicity by two varieties of fern and Indian mustard. Their potential for Hg phyto-remediation application was also investigated. Anatomical, histochemical and biochemical approaches were used to study mercury phyto-toxicity as well as anti-oxidative responses in ferns [Chinese brake fern (P. vittata) and Boston fern (N. exaltata)] and Indian mustard (Florida broadleaf and longstanding) (Brassica juncea L.) grown in a hydroponic system. Phyto-remediation potentials of these plant species were estimated based on their Hg uptake performance with contaminated soils from Oak Ridge (TN, USA). Our results show that mercury exposure led to severe phyto-toxicity accompanied by lipid peroxidation and rapid accumulation of hydrogen peroxide (H 2 O 2 ) in P. vittata, but not in N. exaltata. The two cultivars of fern responded differently to mercury exposure in terms of anti-oxidative enzymes (superoxide dismutase, SOD; catalase, CAT; peroxidase, POD; glutathione reductase, GR). Mercury exposure resulted in the accumulation of ascorbic acid (ASA) and glutathione (GSH) in the shoots of both cultivars of fern. On the other hand, Indian mustard effectively generated an enzymatic antioxidant defense system (especially CAT) to scavenge H 2 O 2 , resulting in lower H 2 O 2 in shoots with higher mercury concentrations. These two cultivars of Indian mustard demonstrated an efficient metabolic defense and adaptation system to mercury-induced oxidative stress. In both varieties of fern and Indian

Determination of heavy metals in soil and different parts of Diplazium esculentum (medicinal fern)

Science.gov (United States)

Jasim, Hind S.; Idris, Mushrifah; Abdullah, Aminah; Kadhum, A. A. H.

2014-09-01

Diplazium esculentum is a widely used medicinal fern in Malaysia and other regions worldwide. Heavy metals in plants should be determined because prolonged human intake of toxic trace elements, even at low doses, results in organ malfunction and causes chronic toxicity. Hence, substantial information should be obtained from plants that grow on soils containing high concentrations of heavy metals. This study aimed to determine the physicochemical characteristics of soil and heavy metal concentrations (Pb, Cr, Mn, Cu, and Zn) in different parts of D. esculentum and soil, which were collected from the fern garden of Universiti Kebangsaan Malaysia. Results showed that heavy metals were highly accumulated in D. esculentum roots.

Using a body sensor network to measure the effect of fatigue on stair climbing performance

International Nuclear Information System (INIS)

Bergmann, Jeroen H M; Smith, Ian C H; Mayagoitia, Ruth E

2012-01-01

In terms of self-rated health, the most important activities of daily living are those involving mobility. Of these activities stair climbing is regarded as the most strenuous. A loss of stair climbing ability with age is normally associated with a loss of muscle strength and power, while other factors that influence muscle function, such as fatigue, are often not taken into account. So far no research has been published on how long-lasting fatigue affects activities of daily living, despite the fact that it has been repeatedly proven, in laboratory settings, to influence muscle force production over long periods of time. Technological advances in body sensor networks (BSNs) now provide a method to measure performance during complex real-life situations. In this study the use of a BSN was explored to investigate the effects of long-lasting fatigue on stair climbing performance in 20 healthy adults. Stair climbing performance was measured before and after a fatiguing protocol using a BSN. Performance was defined by temporal and spatial parameters. Long-lasting fatigue was successfully induced in all participants using an exercise protocol. The BSN showed that post-exercise fatigue did not influence stair climbing times (p > 0.2) and no meaningful changes in joint angles were found. No effect on overall stair climbing performance was found, despite a clear presence of long-lasting fatigue. This study shows that physiological paradigms can be further explored using BSNs. Ecological validity of lab-based measurements can be increased by combining them with BSNs. (paper)

The scaly tree ferns (Cyatheaceae-Polypodiopsida) of Brazil

OpenAIRE

Weigand, Anna; Lehnert, Marcus

2016-01-01

ABSTRACT A synopsis of all scaly tree fern species (Cyatheaceae) occurring in Brazil is presented. We recognize 51 species in three genera [Sphaeropteris one species, Alsophila four species (one subspecies, two varieties), and Cyathea 45 species (one variety) ] with 17 taxa being endemic to Brazil. One hybrid endemic to Brazil is recognized. Further included are five species that have not yet been recorded in Brazil, but are expected here because they are found in adjacent countries and occur...

Climbing performance of Harris' hawks (Parabuteo unicinctus) with added load: Implications for muscle mechanics and for radiotracking

Science.gov (United States)

Pennycuick, C.J.; Fuller, M.R.; McAllister, L.

1989-01-01

Two Harris' hawks were trained to fly along horizontal and climbing flight paths, while carrying loads of various masses, to provide data for estimating available muscle power during short flights. The body mass of both hawks was about 920 g, and they were able to carry loads up to 630 g in horizontal flight. The rate of climb decreased with increasing all-up mass, as also did the climbing power (product of weight and rate of climb). Various assumptions about the aerodynamic power in low-speed climbs led to estimates of the maximum power output of the flight muscles ranging from 41 to 46 W. This, in turn, would imply a stress during shortening of around 210 kPa. The effects of a radio package on a bird that is raising young should be considered in relation to the food load that the forager can normally carry, rather than in relation to its body mass.

Historical reconstruction of climatic and elevation preferences and the evolution of cloud forest-adapted tree ferns in Mesoamerica.

Science.gov (United States)

Sosa, Victoria; Ornelas, Juan Francisco; Ramírez-Barahona, Santiago; Gándara, Etelvina

2016-01-01

Cloud forests, characterized by a persistent, frequent or seasonal low-level cloud cover and fragmented distribution, are one of the most threatened habitats, especially in the Neotropics. Tree ferns are among the most conspicuous elements in these forests, and ferns are restricted to regions in which minimum temperatures rarely drop below freezing and rainfall is high and evenly distributed around the year. Current phylogeographic data suggest that some of the cloud forest-adapted species remained in situ or expanded to the lowlands during glacial cycles and contracted allopatrically during the interglacials. Although the observed genetic signals of population size changes of cloud forest-adapted species including tree ferns correspond to predicted changes by Pleistocene climate change dynamics, the observed patterns of intraspecific lineage divergence showed temporal incongruence. Here we combined phylogenetic analyses, ancestral area reconstruction, and divergence time estimates with climatic and altitudinal data (environmental space) for phenotypic traits of tree fern species to make inferences about evolutionary processes in deep time. We used phylogenetic Bayesian inference and geographic and altitudinal distribution of tree ferns to investigate ancestral area and elevation and environmental preferences of Mesoamerican tree ferns. The phylogeny was then used to estimate divergence times and ask whether the ancestral area and elevation and environmental shifts were linked to climatic events and historical climatic preferences. Bayesian trees retrieved Cyathea, Alsophyla, Gymnosphaera and Sphaeropteris in monophyletic clades. Splits for species in these genera found in Mesoamerican cloud forests are recent, from the Neogene to the Quaternary, Australia was identified as the ancestral area for the clades of these genera, except for Gymnosphaera that was Mesoamerica. Climate tolerance was not divergent from hypothesized ancestors for the most significant

Historical reconstruction of climatic and elevation preferences and the evolution of cloud forest-adapted tree ferns in Mesoamerica

Directory of Open Access Journals (Sweden)

Victoria Sosa

2016-11-01

Full Text Available Background Cloud forests, characterized by a persistent, frequent or seasonal low-level cloud cover and fragmented distribution, are one of the most threatened habitats, especially in the Neotropics. Tree ferns are among the most conspicuous elements in these forests, and ferns are restricted to regions in which minimum temperatures rarely drop below freezing and rainfall is high and evenly distributed around the year. Current phylogeographic data suggest that some of the cloud forest-adapted species remained in situ or expanded to the lowlands during glacial cycles and contracted allopatrically during the interglacials. Although the observed genetic signals of population size changes of cloud forest-adapted species including tree ferns correspond to predicted changes by Pleistocene climate change dynamics, the observed patterns of intraspecific lineage divergence showed temporal incongruence. Methods Here we combined phylogenetic analyses, ancestral area reconstruction, and divergence time estimates with climatic and altitudinal data (environmental space for phenotypic traits of tree fern species to make inferences about evolutionary processes in deep time. We used phylogenetic Bayesian inference and geographic and altitudinal distribution of tree ferns to investigate ancestral area and elevation and environmental preferences of Mesoamerican tree ferns. The phylogeny was then used to estimate divergence times and ask whether the ancestral area and elevation and environmental shifts were linked to climatic events and historical climatic preferences. Results Bayesian trees retrieved Cyathea, Alsophyla, Gymnosphaera and Sphaeropteris in monophyletic clades. Splits for species in these genera found in Mesoamerican cloud forests are recent, from the Neogene to the Quaternary, Australia was identified as the ancestral area for the clades of these genera, except for Gymnosphaera that was Mesoamerica. Climate tolerance was not divergent from

Tear ferning in normal dogs and dogs with keratoconjunctivitis sicca ...

African Journals Online (AJOL)

This study evaluates tear ferning as an ancillary technique for the evaluation of the canine tear film in normal eyes and eyes affected by keratoconjunctivitis sicca (KCS). Thirty dogs with KCS and 50 control dogs with normal tear film were evaluated with a full ophthalmoscopic examination and a Schirmer tear test type 1 ...

Western sword fern avoids the extreme drought of 2012-2014

Science.gov (United States)

Emily E. Burns; Peter Cowan; Wendy Baxter; Deborah Zierten; Jarmilla Pittermann

2017-01-01

The California drought of 2012 to 2014 was the most severe drought on record for the last century and likely millennium. Warm temperatures with below-average precipitation compounded over the three-year period, creating significant and sustained aridity over the course of three growing seasons throughout the coast redwood ecosystem. The citizen science project, Fern...

Research on Centroid Position for Stairs Climbing Stability of Search and Rescue Robot

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Yan Guo

2011-01-01

Full Text Available This paper represents the relationship between the stability of stairs climbing and the centroid position of the search and rescue robot. The robot system is considered as a mass point-plane model and the kinematics features are analyzed to find the relationship between centroid position and the maximal pitch angle of stairs the robot could climb up. A computable function about this relationship is given in this paper. During the stairs climbing, there is a maximal stability-keeping angle depends on the centroid position and the pitch angle of stairs, and the numerical formula is developed about the relationship between the maximal stability-keeping angle and the centroid position and pitch angle of stairs. The experiment demonstrates the trustworthy and correction of the method in the paper.

Fuel management optimization in pressure water reactors with hexagonal geometry using hill climbing method

International Nuclear Information System (INIS)

Andres Diaz, J.; Quintero, Ruben; Melian, Manuel; Rosete, Alejandro

2000-01-01

In this work the general-purpose optimization method, Hill Climbing, was applied to the Fuel Management Optimization problem in PWR reactors, WWER type. They were carried out a series of experiments in order to study the performance of Hill Climbing. It was proven two starting point for initialize the search: a reload configuration by project and a reload configuration generated with the application of a minimal knowledge of the problem. It was also studied the effect of imposing constraints based on the physics of the reactor in order to reduce the number of possible solutions to be generated. The operator used in Hill Climbing was defined as a binary exchange of fuel assemblies. For the simulation of each generated configuration, the tridimensional simulator program SPPS-1 was used. It was formulated an objective function with power peaking constraint to guide the search. As results, a methodology ws proposed for the In-core Fuel Management Optimization in hexagonal geometry, and the feasibility of the application of the Hill Climbing to this type of problem was demonstrated. (author)

Hill climbing algorithms and trivium

DEFF Research Database (Denmark)

Borghoff, Julia; Knudsen, Lars Ramkilde; Matusiewicz, Krystian

2011-01-01

This paper proposes a new method to solve certain classes of systems of multivariate equations over the binary field and its cryptanalytical applications. We show how heuristic optimization methods such as hill climbing algorithms can be relevant to solving systems of multivariate equations....... A characteristic of equation systems that may be efficiently solvable by the means of such algorithms is provided. As an example, we investigate equation systems induced by the problem of recovering the internal state of the stream cipher Trivium. We propose an improved variant of the simulated annealing method...

Do ferns and lycophytes function as medicinal plants? A study of their low representation in traditional pharmacopoeias.

Science.gov (United States)

Reinaldo, Rafael Corrêa Prota dos Santos; Santiago, Augusto César Pessôa; Medeiros, Patrícia Muniz; Albuquerque, Ulysses Paulino

2015-12-04

Ethnobotany is becoming an important tool for understanding how traditional medical systems are organized and which variables affect their structure and dynamics. However, some phenomena observed in ethnobotanical studies led us to question whether such phenomena are real or methodological artifacts. The small proportion of ferns and lycophytes in ethnobotanical surveys of medicinal plants is one such phenomenon, and its causes should be identified using different approach levels. The present study aimed to clarify the reasons for a low representation of these two groups in studies of medicinal plants. The present study considered the following hypotheses: 1) ferns and lycophytes are little represented in different ethnobotanical studies because of inadequate data collection methods to record these species; 2) ferns and lycophytes are little represented because of the local perception of their low therapeutic efficacy; and 3) species of ferns and lycophytes are represented in local pharmacopoeias in proportion to the size of their families. We chose rural communities from Chapada do Araripe, Northeast Brazil to test our hypotheses. Data on the medicinal plant repertoires of the communities and on the perceived therapeutic efficacy of ferns were obtained using two different methods, semi-structured interviews associated with free lists and a checklist interview, both applied to local specialists. The resulting data were analyzed differently for each test. In addition, data regarding the total flora x medicinal flora ratio were obtained with a floristic survey and accessing data banks from previous studies performed by our research team. All hypotheses were confirmed, showing that all three factors contributed to the low representation of these plant groups as medicinal resources. The present study showed that free-list interviews are not a good method to access traditional knowledge of medicinal ferns and lycophytes and that the use of visual stimuli can help the

Piper (Piperaceae) in New Guinea: the climbing species

NARCIS (Netherlands)

Gardner, R.O.

2012-01-01

Sixteen climbing Piper species are accepted for New Guinea. The three endemics, P. arfakianum, P. subcanirameum and P. versteegii, are fully described. Eight taxa of unclear circumscription are noted. A new variety of P. macropiper, endemic to Morobe Province of Papua New Guinea, is described. The

Construct Validity and Test-Retest Reliability of the Climbing Stairs Questionnaire in Lower-Limb Amputees

NARCIS (Netherlands)

de Laat, Fred A.; Rommers, Gerardus M.; Geertzen, Jan H.; Roorda, Leo D.

de Laat FA, Rommers GM, Geertzen JH, Roorda LD. Construct validity and test-retest reliability of the Climbing Stairs Questionnaire in lower-limb amputees. Arch Phys Med Rehabil 2010;91:1396-401. Objective: To investigate the construct validity and test-retest reliability of the Climbing Stairs

Host range and genetic relatedness of Colletotrichum acutatum isolates from fruit crops and leatherleaf fern in Florida.

Science.gov (United States)

MacKenzie, S J; Peres, N A; Barquero, M P; Arauz, L F; Timmer, L W

2009-05-01

Isolates of Colletotrichum acutatum were collected from anthracnose-affected strawberry, leatherleaf fern, and Key lime; ripe-rot-affected blueberry; and postbloom fruit drop (PFD)-affected sweet orange in Florida. Additional isolates from ripe-rot-affected blueberry were collected from Georgia and North Carolina and from anthracnose-affected leatherleaf fern in Costa Rica. Pathogenicity tests on blueberry and strawberry fruit; foliage of Key lime, leatherleaf fern, and strawberry; and citrus flowers showed that isolates were highly pathogenic to their host of origin. Isolates were not pathogenic on foliage of heterologous hosts; however, several nonhomologous isolates were mildly or moderately pathogenic to citrus flowers and blueberry isolates were pathogenic to strawberry fruit. Based on sequence data from the internal transcribed spacer (ITS)1-5.8S rRNA-ITS2 region of the rDNA repeat, the glutaraldehyde-3-phosphate dehydrogenase intron 2 (G3PD), and the glutamine synthase intron 2 (GS), isolates from the same host were identical or very similar to each other and distinct from those isolated from other hosts. Isolates from leatherleaf fern in Florida were the only exception. Among these isolates, there were two distinct G3PD and GS sequences that occurred in three of four possible combinations. Only one of these combinations occurred in Costa Rica. Although maximum parsimony trees constructed from genomic regions individually displayed little or no homoplasy, there was a lack of concordance among genealogies that was consistent with a history of recombination. This lack of concordance was particularly evident within a clade containing PFD, Key lime, and leatherleaf fern isolates. Overall, the data indicated that it is unlikely that a pathogenic strain from one of the hosts examined would move to another of these hosts and produce an epidemic.

Vestigios de Alvar Aalto en la opera prima de Antonio Fernández Alba (1959-62

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Lucía C. Pérez-Moreno

2018-04-01

Full Text Available La obra de Antonio Fernández Alba de los años sesenta ha sido fundamentalmente calificada de orgánica aludiendo a sus consonancias con la arquitectura de Alvar Aalto. Este texto ahonda en la lectura que Fernández Alba presentó sobre la cultura finesa en varios escritos publicados en la revista madrileña Arquitectura, entre los que destaca el ensayo “Valores humanos y estéticos en el diseño finlandés” publicado en 1962. Reflexiones presentadas en este texto tomaron forma en el colegio Nuestra Señora Santa María en Madrid, un proyecto en el que Fernández Alba estaba trabajando en estos mismos años. Sin eludir la condición de colegio católico y femenino del proyecto, se reflexiona en torno a decisiones proyectuales que ponen de manifestó el interés de Fernández Alba por ofrecer a las niñas educadas en sus espacios una arquitectura propicia para el juego, conectada con la naturaleza circundante, no regida por formas preconcebidas, amable en la elección de sus materiales y libre en el uso y disfrute de sus dependencias. En definitiva, una arquitectura que tuvo en cuenta las necesidades psicofísicas de alumnas y profesorado o una arquitectura humanizada, aludiendo al conocido ensayo de Alvar Aalto escrito en 1940.

Water ferns Azolla spp. (Azollaceae as new host plants for the small China-mark moth, Cataclysta lemnata (Linnaeus, 1758 (Lepidoptera, Crambidae, Acentropinae

Directory of Open Access Journals (Sweden)

Atousa Farahpour-Haghani

2017-01-01

Full Text Available Water ferns (Azolla spp., Azollaceae are reported for the first time as host plants for the larvae of the small China-mark moth Cataclysta lemnata (Linnaeus (Lepidoptera: Crambidae: Acentropinae in rice fields and waterways of northern Iran. Cataclysta lemnata is a semi-aquatic species that has been recorded to feed on Lemnaceae and a few other aquatic plants. However, it has not been reported before on Azolla spp. Larvae use water fern as food source and shelter and, at high population density in the laboratory, they completely wiped water fern from the water surface. Feeding was confirmed after rearing more than eight continual generations of C. lemnata on water fern in the laboratory. Adults obtained this way are darker and have darker fuscous markings in both sexes compared with specimens previously reported and the pattern remains unchanged after several generations.

Un texto inédito de Wenceslao Fernández Flórez. "¡S.O.S.! ¡Aquí Europa!"

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María Teresa BARBADILLO

2009-11-01

Full Text Available Publicamos aquí un texto inédito de Wenceslao Fernández Flórez contenido en 23 cuartillas escritas de su puño y letra, que me fueron confiadas generosamente por sus sobrinos Wenceslao y Antonio Fernández Flórez. El manuscrito no lleva fecha alguna, y el sobre que lo contenía sólo reproduce el título, con la indicación «Charla radiofónica». Don Antonio Fernández Flórez tiene idea de que data de 1934 ó 35, posiblemente del mes de octubre. No obstante, ni en la prensa de esos años, ni en los archivos del Servicio de Documentación escrita de Radio Nacional de España —en donde nos atendieron con suma amabilidad— queda constancia de esta intervención de Fernández Flórez a través de las ondas.

Dynamic analysis of a bio-inspired climbing robot using ADAMS-Simulink co-simulation

Science.gov (United States)

Chattopadhyay, P.; Dikshit, H.; Majumder, A.; Ghoshal, S.; Maity, A.

2018-04-01

Climbing robot has been an area of interest since the demand of inspection of pipeline, nuclear power plant, and various big structure is growing up rapidly. This paper represents the development of a bio-inspired modular robot which mimics inchworm locomotion during climbing. In the present paper, the climbing motion is achieved only on a flat vertical plane by magnetic adhesion principle. The robot is modelled as a 4-link planar mechanism with three revolute joints actuated by DC servo motors. Sinusoidal gait pattern is used to approximate the motion of an inchworm. The dynamics of the robot is presented by using ADAMS/MATLAB co-simulation methodology. The simulation result gives the maximum value of joint torque during one complete cycle of motion. This torque value is used for the selection of servo motor specifications required to build the prototype.

Characteristics of the scientific researches in sport climbing (review of the articles, theses, programs, methodical works.

Directory of Open Access Journals (Sweden)

Sedliar Yu.V.

2011-04-01

Full Text Available The general estimation of the condition of the scientific developments will presented in sport climbing and on this base is specified the most perspective ways of scientific searching for in this area. Analysis publication reflecting different questions of preparation sport climbing athletes was organized. On base of the analysis of the special literature and coming from generally accepted in home science structure of the knowledge, was ascertained degree of the development different theoretical and practical aspect in this sphere. Discovered increase amount of the experimental studies in sport climbing.

Understory fern community structure, growth and spore production responses to a large-scale hurricane experiment in a Puerto Rico rainforest

Science.gov (United States)

Joanne M. Sharpe; Aaron B. Shiels

2014-01-01

Ferns are abundant in most rainforest understories yet their responses to hurricanes have not been well studied. Fern community structure, growth and spore production were monitored for two years before and five years after a large-scale experiment that simulated two key components of severe hurricane disturbance: canopy openness and debris deposition. The canopy was...

Stair Climbing in a Quadruped Robot

OpenAIRE

Shen-Chiang Chen; Chih-Chung Ko; Cheng-Hsin Li; Pei-Chun Lin

2012-01-01

This paper reports the algorithm of trajectory planning and the strategy of four-leg coordination for quasi-static stair climbing in a quadruped robot. This development is based on the geometrical interactions between robot legs and the stair, starting from single-leg analysis, followed by two-leg collaboration, and then four-leg coordination. In addition, a brief study on the robot’s locomotion stability is also included. Finally, simulation and experimental testing were executed to evaluate...

Epiphytic ferns in swamp forest remnants of the coastal plain of southern Brazil: latitudinal effects on the plant community

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Letícia S. Machado

Full Text Available ABSTRACT Community structure and spatial distribution of epiphytic ferns in swamp forest remnants along the coastal plain of the state of Rio Grande do Sul were analyzed. A total of 440 trees were sampled in fifty-seven 10 x 10 m plots. Each phorophyte was divided into five ecological zones (strata, where all species of epiphytic ferns were recorded. A total of 34 species representing 18 genera in six families were recorded. Polypodiaceae was the most represented family with 17 species, and Microgramma vacciniifolia had the highest epiphytic importance value. Characteristic holoepiphyte was the predominant ecological category, representing 70 % of the species. Ordination analysis showed a gradual change in floristic composition between ecological zones with richness differing significantly between strata. We observed that with increasing latitude there was a decrease in mean temperature and total rainfall, but an increase in frosts. These climatic and phytogeography changes result in a reduction in species richness and a change in the structure of epiphytic fern communities in a north-to-south direction. The importance of swamp forest remnants of the coastal plain to the diversity of epiphytic ferns is discussed.

Robot-assisted practice of gait and stair climbing in nonambulatory stroke patients.

Science.gov (United States)

Hesse, Stefan; Tomelleri, Christopher; Bardeleben, Anita; Werner, Cordula; Waldner, Andreas

2012-01-01

A novel gait robot enabled nonambulatory patients the repetitive practice of gait and stair climbing. Thirty nonambulatory patients with subacute stroke were allocated to two groups. During 60 min sessions every workday for 4 weeks, the experimental group received 30 min of robot training and 30 min of physiotherapy and the control group received 60 min of physiotherapy. The primary variable was gait and stair climbing ability (Functional Ambulation Categories [FAC] score 0-5); secondary variables were gait velocity, Rivermead Mobility Index (RMI), and leg strength and tone blindly assessed at onset, intervention end, and follow-up. Both groups were comparable at onset and functionally improved over time. The improvements were significantly larger in the experimental group with respect to the FAC, RMI, velocity, and leg strength during the intervention. The FAC gains (mean +/- standard deviation) were 2.4 +/- 1.2 (experimental group) and 1.2 +/- 1.5 (control group), p = 0.01. At the end of the intervention, seven experimental group patients and one control group patient had reached an FAC score of 5, indicating an ability to climb up and down one flight of stairs. At follow-up, this superior gait ability persisted. In conclusion, the therapy on the novel gait robot resulted in a superior gait and stair climbing ability in nonambulatory patients with subacute stroke; a higher training intensity was the most likely explanation. A large randomized controlled trial should follow.

Comparison of Genetic Algorithm and Hill Climbing for Shortest Path Optimization Mapping

Directory of Open Access Journals (Sweden)

Fronita Mona

2018-01-01

Full Text Available Traveling Salesman Problem (TSP is an optimization to find the shortest path to reach several destinations in one trip without passing through the same city and back again to the early departure city, the process is applied to the delivery systems. This comparison is done using two methods, namely optimization genetic algorithm and hill climbing. Hill Climbing works by directly selecting a new path that is exchanged with the neighbour’s to get the track distance smaller than the previous track, without testing. Genetic algorithms depend on the input parameters, they are the number of population, the probability of crossover, mutation probability and the number of generations. To simplify the process of determining the shortest path supported by the development of software that uses the google map API. Tests carried out as much as 20 times with the number of city 8, 16, 24 and 32 to see which method is optimal in terms of distance and time computation. Based on experiments conducted with a number of cities 3, 4, 5 and 6 producing the same value and optimal distance for the genetic algorithm and hill climbing, the value of this distance begins to differ with the number of city 7. The overall results shows that these tests, hill climbing are more optimal to number of small cities and the number of cities over 30 optimized using genetic algorithms.

Historical reconstruction of climatic and elevation preferences and the evolution of cloud forest-adapted tree ferns in Mesoamerica

OpenAIRE

Sosa, Victoria; Ornelas, Juan Francisco; Ram?rez-Barahona, Santiago; G?ndara, Etelvina

2016-01-01

Background Cloud forests, characterized by a persistent, frequent or seasonal low-level cloud cover and fragmented distribution, are one of the most threatened habitats, especially in the Neotropics. Tree ferns are among the most conspicuous elements in these forests, and ferns are restricted to regions in which minimum temperatures rarely drop below freezing and rainfall is high and evenly distributed around the year. Current phylogeographic data suggest that some of the cloud forest-adapted...

Development and Initial Validation of a Rock Climbing Craving Questionnaire (RCCQ

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Gareth Roderique-Davies

2018-02-01

Full Text Available Conceptual similarities have been identified between experiences of extreme sports athletes and those with drug and behavioral addictions. Evidence suggests rock climbers experience craving and other withdrawal-like states when abstinent from their sport. However, no studies have attempted to quantitatively measure the craving experienced by participants of any extreme sports. Such a measure could allow a greater understanding of the craving experienced by extreme sports athletes and a comparison of these across sports (e.g., surfing and activities (e.g., drug-use. Therefore, using validated craving measures as a template, the aim of the two studies outlined here was to design and preliminarily validate a subjective multidimensional inventory that could be used to measure craving in the sports of rock-climbing and mountaineering (“RCCQ”. The aim of the first study was to investigate the factor structure of a preliminary measure of craving. Climbers (n = 407 completed the RCCQ. A 3-factor model explained 53.65% of the total variance in item scores. All three factors comprised five items each, which were conceptually labeled as “urge to climb” “negative reinforcement” and “positive reinforcement.” The aim of the second study was to validate the 15-item 3-factor RCCQ resulting from Study 1 using confirmatory factor analysis (CFA. Climbers (n = 254 completed the questionnaire under a climbing-related cue condition or a cue-neutral condition. CFA revealed a good model fit and that all individual parameter estimates were significant and standard errors were within reasonable limits once item 13 was removed from Factor 1. Study 1 supports the multi-dimensional nature of rock climbing craving and shows parallels with substance-related craving in reflecting intention and positive (desire and negative (withdrawal reinforcement. Study 2 confirms this factor structure and gives initial validation to the measure with evidence that these

Invariant Hough Random Ferns for Object Detection and Tracking

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Yimin Lin

2014-01-01

Full Text Available This paper introduces an invariant Hough random ferns (IHRF incorporating rotation and scale invariance into the local feature description, random ferns classifier training, and Hough voting stages. It is especially suited for object detection under changes in object appearance and scale, partial occlusions, and pose variations. The efficacy of this approach is validated through experiments on a large set of challenging benchmark datasets, and the results demonstrate that the proposed method outperforms state-of-the-art conventional methods such as bounding-box-based and part-based methods. Additionally, we also propose an efficient clustering scheme based on the local patches’ appearance and their geometric relations that can provide pixel-accurate, top-down segmentations from IHRF back-projections. This refined segmentation can be used to improve the quality of online object tracking because it avoids the drifting problem. Thus, an online tracking framework based on IHRF, which is trained and updated in each frame to distinguish and segment the object from the background, is established. Finally, the experimental results on both object segmentation and long-term object tracking show that this method yields accurate and robust tracking performance in a variety of complex scenarios, especially in cases of severe occlusions and nonrigid deformations.

Ants inhabiting myrmecophytic ferns regulate the distribution of lianas on emergent trees in a Bornean tropical rainforest.

Science.gov (United States)

Tanaka, Hiroshi O; Itioka, Takao

2011-10-23

Little is known about the spatial distribution of lianas on emergent trees in tropical rainforests and the factors affecting this distribution. The present study investigated the effects of an arboreal ant species, Crematogaster difformis, which forms myrmecophytic symbioses with two epiphytic ferns, Lecanopteris sp. and Platycerium sp., on the spatial distribution of lianas associated with emergent trees. Living lianas were placed onto trunk surfaces inside and outside the territories of the ants in the canopy, to examine their ability to remove them. The number of leaves pruned by the ants was significantly higher on lianas inside than outside their territories. The spatial overlap of the distributions of lianas and the two ferns on emergent trees were then examined. The frequency of liana colonization of tree crowns was found to be significantly lower on trees with than without ferns. Under the natural conditions, C. difformis workers were observed biting and pruning the lianas. These results suggest that C. difformis regulates the distribution of lianas on emergent trees.

Transition Analysis and Its Application to Global Path Determination for a Biped Climbing Robot

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Haifei Zhu

2018-01-01

Full Text Available Biped climbing robots are considered good assistants and (or substitutes for human workers carrying out high-rise truss-associated routine tasks. Flexible locomotion on three-dimensional complex trusses is a fundamental skill for these robots. In particular, the capability to transit from one structural member to another is paramount for switching objects to be climbed upon. In this paper, we study member-to-member transition and its utility in global path searching for biped climbing robots. To compute operational regions for transition, hierarchical inspection of safety, reachability, and accessibility of grips is taken into account. A novel global path rapid determination approach is subsequently proposed based on the transition analysis. This scheme is efficient for finding feasible routes with respect to the overall structural environment, which also benefits the subsequent grip and motion planning. Simulations are conducted with Climbot, our self-developed biped climbing robot, to verify the efficiency of the presented method. Results show that our proposed method is able to accurately determine the operational region for transition within tens of milliseconds and can obtain global paths within seconds in general.

Chemotaxonomy for naturally macerated tree-fern cuticles (Medullosales and Marattiales), Carboniferous Sydney and Mabou Sub-Basins, Nova Scotia, Canada

Energy Technology Data Exchange (ETDEWEB)

Zodrow, Erwin L. [Department of Earth Sciences, University College of Cape Breton, PO Box 5300, Nova Scotia, B1P 6L2 Sydney (Canada); Mastalerz, Maria [Indiana Geological Survey, Indiana University, 611 North Walnut Grove, 47405-2208 Bloomington, IN (United States)

2001-07-01

Naturally macerated cuticles (NMC) and one synangium, representing medullosalean and marattialean tree-fern species, from two Carboniferous coalfields in Nova Scotia, Canada, are investigated. The samples were analyzed by infrared spectroscopy (FTIR), and by pyrolysis-gas chromatograph/mass spectrometry (py-Gc/Ms) techniques in search for chemical signatures that would help in developing a chemotaxonomic classification of Carboniferous fern species, assuming genetically dependent make-up of cuticles. FTIR-derived CH{sub 2}/CH{sub 3} ratios, in conjunction with contributions from carboxyl groups, demonstrated a better potential for discriminating between medullosalean genera and species than molecular signatures obtained by py-Gc/Ms. However, the latter provided better data for differentiating medullosalean from marattialean tree ferns as a group. Changes in the chemical make-up of naturally macerated cuticles due to sample preparation are discussed.

The cyanobiont in an Azolla fern is neither Anabaena nor Nostoc.

Science.gov (United States)

Baker, Judith A; Entsch, Barrie; McKay, David B

2003-12-05

The cyanobacterial symbionts in the fern Azolla have generally been ascribed to either the Anabaena or Nostoc genera. By using comparisons of the sequences of the phycocyanin intergenic spacer and a fragment of the 16S rRNA, we found that the cyanobiont from an Azolla belongs to neither of these genera.

Climbing the Needs Pyramids

Directory of Open Access Journals (Sweden)

J. C. Lomas

2013-08-01

Full Text Available Abraham Maslow’s theory of human adult motivation is often represented by a pyramid image showing two proposals: First, the five needs stages in emergent order of hierarchical ascension and second, a percentage of the adult population suggested to occupy each needs tier. Specifically, Maslow proposed that adults would be motivated to satisfy their unfilled needs until they reached the hierarchy’s apex and achieved self-transcendence. Yet how adults can purposefully ascend Maslow’s pyramid through satisfying unfilled needs remains elusive. This brief article challenges this on the theory’s 70th anniversary by presenting a new image of the needs hierarchy, based on ecological design principles to support adults’ purposeful endeavors to climb the needs pyramid.

Dislocation climb and interstitial loop growth under cascade damage irradiation

International Nuclear Information System (INIS)

Woo, C.H.; Semenov, A.A.

1993-01-01

The effects of intracascade clustering and recombination in radiation damage have been considered previously in semiquantitative calculations involving vacancy accumulation at voids, within the concept of production bias. To model void swelling and microstructural evolution quantitatively, similar effects on dislocation climb and interstitial loop growth have to be considered. In this regard, at elevated temperatures (such as in the peak-swelling temperature regime), the concentration of freely migrating vacancies is much higher than that of the interstitials, owing to the evaporation from the primary vacancy clusters (i.e. those produced by intracascade clustering). It is not immediately obvious how the dislocations can be net interstitials sinks, and hence that the observed nucleation and growth of the interstitial loops at elevated temperatures can be correctly predicted as in the conventional theory. To address these basic questions, a rate theory model is formulated in this paper, which describes the dislocation climb and loop growth in the presence of intracascade primary clusters. Within this model, conservation equations for the concentrations and average radii of the two kinds of primary cluster are derived, and the corresponding steady-state concentrations and average radii are calculated. From this, the dislocation climb velocity and interstitial loop growth rate are calculated. On the basis of the results of this calculation, some of the basic questions of production bias are discussed. (Author)

Penerapan Metode Hill Climbing Pada Sistem Informasi Geografis Untuk Mencari Lintasan Terpendek

Directory of Open Access Journals (Sweden)

Eka Vickraien Dangkua

2016-04-01

Full Text Available Heuristic search methods is one of the methods commonly in use in finding the shortest path, one of which, namely the methods Hill Climbing process where testing is done using heuristic functions. Problems generally encountered is the shortest path search to solve the problem of distance can be changed into a graph structure, where the point of declaring the city and the State line that connects the two cities. From the logic so that it can locate destinations and save on travel costs. The hallmarks of this algorithm are all possible solutions will have then checked one by one from the left side, so it will be obtained solutions with optimal results. On a Hill Climbing method according to case using geographic information systems as a tool in making a decision, by way of collect, examine, and analyze information related to digital map. with a combination of Hill Climbing method and geographic information systems can result in an application that is certainly feasible for use in the search path problems.   Keywords: Hill Climbin method; digital map; Geographic Information Systems

Evolutionary Novelty versus Exaptation: Oral Kinematics in Feeding versus Climbing in the Waterfall-Climbing Hawaiian Goby Sicyopterus stimpsoni

OpenAIRE

Cullen, Joshua A.; Maie, Takashi; Schoenfuss, Heiko L.; Blob, Richard W.

2013-01-01

Species exposed to extreme environments often exhibit distinctive traits that help meet the demands of such habitats. Such traits could evolve independently, but under intense selective pressures of extreme environments some existing structures or behaviors might be coopted to meet specialized demands, evolving via the process of exaptation. We evaluated the potential for exaptation to have operated in the evolution of novel behaviors of the waterfall-climbing gobiid fish genus Sicyopterus. T...

Leading Organizational Change Is Like Climbing a Mountain

Science.gov (United States)

Zimmerman, Judith

2004-01-01

Leading organizational change is like climbing a mountain. Transformational leaders must prepare to lead change, understand the process and nature of change, and provide the essential gear so that those involved can be successful. The author draws on the literature and personal experiences as a hiker and change leader to provide a guide for…

Continental scale patterns and predictors of fern richness and phylogenetic diversity

Directory of Open Access Journals (Sweden)

Nathalie eNagalingum

2015-04-01

Full Text Available Because ferns have a wide range of habitat preferences and are widely distributed, they are an ideal group for understanding how diversity is distributed. Here we examine fern diversity on a broad-scale using standard and corrected richness measures as well as phylogenetic indices; in addition we determine the environmental predictors of each diversity metric. Using the combined records of Australian herbaria, a dataset of over 60,000 records was obtained for 89 genera to infer richness. A phylogenetic tree of all the genera was constructed and combined with the herbarium records to obtain phylogenetic diversity patterns. A hotspot of both taxic and phylogenetic diversity occurs in the Wet Tropics of northeastern Australia. Although considerable diversity is distributed along the eastern coast, some important regions of diversity are identified only after sample-standardization of richness and through the phylogenetic metric. Of all of the metrics, annual precipitation was identified as the most explanatory variable, in part, in agreement with global and regional fern studies. Precipitation was combined with a different variable for each different metric. For corrected richness, precipitation is combined with temperature seasonality, while correlation of phylogenetic diversity to precipitation plus radiation indicates support for the species-energy hypothesis. Significantly high and significantly low phylogenetic diversity were found in geographically separate areas. These areas are correlated with different climatic conditions such as seasonality in precipitation. The use of phylogenetic metrics identifies additional areas of significant diversity, some of which have not been revealed using traditional taxonomic analyses, suggesting that different ecological and evolutionary processes have operated over the continent. Our study demonstrates that it is possible and vital to incorporate evolutionary metrics when inferring biodiversity hotspots

Is there foul play in the leaf pocket? The metagenome of floating fern

NARCIS (Netherlands)

Dijkhuizen, L.W.; Brouwer, P.; Bolhuis, H.; Reichart, G.-J.; Koppers, N.; Huettel, B.; Bolger, A.M.; Li, F.-W.; Cheng, S.; Liu, X.; Wong, G.K.-S.; Pryer, K.; Weber, A.; Bräutigam, A.; Schluepmann, H.

2018-01-01

Dinitrogen fixation by Nostoc azollae residing in specialized leaf pockets supports prolific growth of the floating fern Azolla filiculoides. To evaluate contributions by further microorganisms, the A. filiculoides microbiome and nitrogen metabolism in bacteria persistently associated with Azolla

Explotación de peces asociada a la pesquería artesanal de langosta de Juan Fernández (Jasus frontalis

Directory of Open Access Journals (Sweden)

Mauricio Ahumada

2014-03-01

Full Text Available Para contribuir al conocimiento de la explotación de peces asociada a la pesquería de langosta de Juan Fernández, se monitorearon 157 salidas de pesca durante la temporada 2010-2011. Se capturaron 10.462 ejemplares correspondientes a 19 especies de peces, tres de las cuales concentraron el 94% de la captura en número: jurel de Juan Fernández (Pseudocaranx chilensis (45%, breca (Nemadactylus gayi (41% y anguila morena (Gymnothoraxporphyreus (8%. Las capturas totales estimadas fueron 40, 24 y 13 ton de breca, jurel de Juan Fernández y anguila morena, respectivamente. El 97% de los ejemplares de peces capturados fueron utilizados como carnada de peces o langosta.

Biodiversity and spatial distribution of epiphytic ferns on Alsophila setosa Kaulf. (Cyatheaceae) caudices in Rio Grande do Sul, Brazil.

Science.gov (United States)

Schmitt, J L; Windisch, P G

2010-08-01

The extractive exploitation of the tree fern Alsophila setosa Kaulf. alters forest formations and diminishes the availability of micro-habitat for epiphytes. A survey of epiphytic fern communities on A. setosa at 16 study sites in different forest formations in the State of Rio Grande do Sul, Brazil, documented the occurrence of 31 species representing 16 genera and six families. The greatest richness of species occurred in Polypodiaceae (39%) and in the genus Asplenium L. (22%). Habitual holoepiphyte was the predominant ecological category, representing 61% of the species. Similarity analysis demonstrated heterogeneity in the composition of the epiphytic ferns at the study sites and indicated that the vegetation type is not the main factor for floristic difference. The lowest total specific richness (5) was recorded for the seasonal deciduous forest site. The majority of the sites presented similar averages of phorophyte height and epiphyte richness per caudex. In 25% of the sites the height of the host plants presented significant correlation with specific richness. Considering that the majority of the epiphytes are habitual and that some of them occur exclusively or preferentially on tree ferns, the maintenance of these host plants in the vegetation is essential for the conservation of epiphytic species.

Cytokinin-induced promotion of root meristem size in the fern Azolla supports a shoot-like origin of euphyllophyte roots.

Science.gov (United States)

de Vries, Jan; Fischer, Angela Melanie; Roettger, Mayo; Rommel, Sophie; Schluepmann, Henriette; Bräutigam, Andrea; Carlsbecker, Annelie; Gould, Sven Bernhard

2016-01-01

The phytohormones cytokinin and auxin orchestrate the root meristem development in angiosperms by determining embryonic bipolarity. Ferns, having the most basal euphyllophyte root, form neither bipolar embryos nor permanent embryonic primary roots but rather an adventitious root system. This raises the questions of how auxin and cytokinin govern fern root system architecture and whether this can tell us something about the origin of that root. Using Azolla filiculoides, we characterized the influence of IAA and zeatin on adventitious fern root meristems and vasculature by Nomarski microscopy. Simultaneously, RNAseq analyses, yielding 36,091 contigs, were used to uncover how the phytohormones affect root tip gene expression. We show that auxin restricts Azolla root meristem development, while cytokinin promotes it; it is the opposite effect of what is observed in Arabidopsis. Global gene expression profiling uncovered 145 genes significantly regulated by cytokinin or auxin, including cell wall modulators, cell division regulators and lateral root formation coordinators. Our data illuminate both evolution and development of fern roots. Promotion of meristem size through cytokinin supports the idea that root meristems of euphyllophytes evolved from shoot meristems. The foundation of these roots was laid in a postembryonically branching shoot system. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Biodiversity and spatial distribution of epiphytic ferns on Alsophila setosa Kaulf. (Cyatheaceae caudices in Rio Grande do Sul, Brazil

Directory of Open Access Journals (Sweden)

JL. Schmitt

Full Text Available The extractive exploitation of the tree fern Alsophila setosa Kaulf. alters forest formations and diminishes the availability of micro-habitat for epiphytes. A survey of epiphytic fern communities on A. setosa at 16 study sites in different forest formations in the State of Rio Grande do Sul, Brazil, documented the occurrence of 31 species representing 16 genera and six families. The greatest richness of species occurred in Polypodiaceae (39% and in the genus Asplenium L. (22%. Habitual holoepiphyte was the predominant ecological category, representing 61% of the species. Similarity analysis demonstrated heterogeneity in the composition of the epiphytic ferns at the study sites and indicated that the vegetation type is not the main factor for floristic difference. The lowest total specific richness (5 was recorded for the seasonal deciduous forest site. The majority of the sites presented similar averages of phorophyte height and epiphyte richness per caudex. In 25% of the sites the height of the host plants presented significant correlation with specific richness. Considering that the majority of the epiphytes are habitual and that some of them occur exclusively or preferentially on tree ferns, the maintenance of these host plants in the vegetation is essential for the conservation of epiphytic species.

Piper (Piperaceae) in the Solomon Islands: the climbing species

NARCIS (Netherlands)

Gardner, R.O.

2010-01-01

Eleven climbing species of Piper in the Solomon Islands are recognized: P. abbreviatum, P. betle, P. bosnicanum, P. caninum, P. celtidiforme, P. fragile, P. insectifugum (syn. P. austrocaledonicum), P. interruptum, P. macropiper, P. majusculum, and, as the only endemic, P. sclerophloeum, for which a

Piper (Piperaceae) in the Philippine Islands: the climbing species

NARCIS (Netherlands)

Gardner, R.O.

2006-01-01

Piper in the Philippine Islands is reviewed. Fifteen climbing species are recognized (many fewer than in previous treatments) and distinguished in a key. Most are widely distributed through Malesia, with ranges that end eastwards in the Solomon Islands or Australia. Piper myrmecophilum, the only

Chemotaxonomy for naturally macerated tree-fern cuticles (Medullosales and Marattiales), Carboniferous Sydney and Mabou Sub-Basins, Nova Scotia, Canada

Science.gov (United States)

Zodrow, E.L.; Mastalerz, Maria

2001-01-01

Naturally macerated cuticles (NMC) and one synangium, representing medullosalean and marattialean tree-fern species, from two Carboniferous coalfields in Nova Scotia, Canada, are investigated. The samples were analyzed by infrared spectroscopy (FTIR), and by pyrolysis-gas chromatograph/mass spectrometry (py-Gc/Ms) techniques in search for chemical signatures that would help in developing a chemotaxonomic classification of Carboniferous fern species, assuming genetically dependent make-up of cuticles. FTIR-derived CH2/CH3 ratios, in conjunction with contributions from carboxyl groups, demonstrated a better potential for discriminating between medullosalean genera and species than molecular signatures obtained by py-Gc/Ms. However, the latter provided better data for differentiating medullosalean from marattialean tree ferns as a group. Changes in the chemical make-up of naturally macerated cuticles due to sample preparation are discussed. ?? 2001 Elsevier Science B.V. All rights reserved.

Nutrient composition of climbing and prostrate vegetable cowpea ...

African Journals Online (AJOL)

The study evaluated the nutrient content of different accessions of two vegetable cowpea genotypes. The mineral content of the vegetable cowpea accessions were high. Potassium content of the accessions of the climbing genotype “Akidi enu” ranged from 1.25 to 1.52% with a mean value of 1.43 ± 0.13% while in the ...

Evolution and classification of Elaphoglossum and Asplenium ferns on Cuba, and discovery of a Miocene Elaphoglossum in Dominican amber

OpenAIRE

Lóriga Piñero, Josmaily

2018-01-01

This dissertation deals with the systematics and evolution of Neotropical ferns of the genera Elaphoglossum and Asplenium, with particular focus on the species of Cuba and the West Indies. It also includes an analysis and description of an Elaphoglossum frond fragment preserved in Miocene Dominican amber. The worldwide genera Elaphoglossum with 600 species and Asplenium with 685 species are the most species-rich groups of leptosporangiate ferns. On Cuba, Elaphoglossum has 34 species and Asple...

Metabolic Adaptation, a Specialized Leaf Organ Structure and Vascular Responses to Diurnal N2 Fixation by Nostoc azollae Sustain the Astonishing Productivity of Azolla Ferns without Nitrogen Fertilizer.

Science.gov (United States)

Brouwer, Paul; Bräutigam, Andrea; Buijs, Valerie A; Tazelaar, Anne O E; van der Werf, Adrie; Schlüter, Urte; Reichart, Gert-Jan; Bolger, Anthony; Usadel, Björn; Weber, Andreas P M; Schluepmann, Henriette

2017-01-01

Sustainable agriculture demands reduced input of man-made nitrogen (N) fertilizer, yet N 2 fixation limits the productivity of crops with heterotrophic diazotrophic bacterial symbionts. We investigated floating ferns from the genus Azolla that host phototrophic diazotrophic Nostoc azollae in leaf pockets and belong to the fastest growing plants. Experimental production reported here demonstrated N-fertilizer independent production of nitrogen-rich biomass with an annual yield potential per ha of 1200 kg -1 N fixed and 35 t dry biomass. 15 N 2 fixation peaked at noon, reaching 0.4 mg N g -1 dry weight h -1 . Azolla ferns therefore merit consideration as protein crops in spite of the fact that little is known about the fern's physiology to enable domestication. To gain an understanding of their nitrogen physiology, analyses of fern diel transcript profiles under differing nitrogen fertilizer regimes were combined with microscopic observations. Results established that the ferns adapted to the phototrophic N 2 -fixing symbionts N. azollae by (1) adjusting metabolically to nightly absence of N supply using responses ancestral to ferns and seed plants; (2) developing a specialized xylem-rich vasculature surrounding the leaf-pocket organ; (3) responding to N-supply by controlling transcripts of genes mediating nutrient transport, allocation and vasculature development. Unlike other non-seed plants, the Azolla fern clock is shown to contain both the morning and evening loops; the evening loop is known to control rhythmic gene expression in the vasculature of seed plants and therefore may have evolved along with the vasculature in the ancestor of ferns and seed plants.

Geometry, Allometry and Biomechanics of Fern Leaf Petioles: Their Significance for the Evolution of Functional and Ecological Diversity Within the Pteridaceae

Directory of Open Access Journals (Sweden)

Jennifer N. Mahley

2018-03-01

Full Text Available Herbaceous plants rely on a combination of turgor, ground tissues and geometry for mechanical support of leaves and stems. Unlike most angiosperms however, ferns employ a sub-dermal layer of fibers, known as a hypodermal sterome, for support of their leaves. The sterome is nearly ubiquitous in ferns, but nothing is known about its role in leaf biomechanics. The goal of this research was to characterize sterome attributes in ferns that experience a broad range of mechanical stresses, as imposed by their aquatic, xeric, epiphytic, and terrestrial niches. Members of the Pteridaceae meet this criteria well. The anatomical and functional morphometrics along with published values of tissue moduli were used to model petiole flexural rigidity and susceptibility to buckling in 20 species of the Pteridaceae. Strong allometric relationships were observed between sterome thickness and leaf size, with the sterome contributing over 97% to petiole flexural rigidity. Surprisingly, the small-statured cheilanthoid ferns allocated the highest fraction of their petiole to the sterome, while large leaves exploited aspects of geometry (second moment of area to achieve bending resistance. This pattern also revealed an economy of function in which increasing sterome thickness was associated with decreasing fiber cell reinforcement, and fiber wall fraction. Lastly, strong petioles were associated with durable leaves, as approximated by specific leaf area. This study reveals meaningful patterns in fern leaf biomechanics that align with species leaf size, sterome attributes and life-history strategy.

Climbing Up the Technology Ladder? High-Technology Exports in China and Latin America

OpenAIRE

Gallagher, Kevin P.; Porzecanski, Roberto

2008-01-01

In this paper we determine the “dynamic revealed competitiveness position” (DRCP) of nations for high technology exports between 1980 and 2005. We find that the developed world has lost significant market share in high technology and that China has climbed the high technology ladder during this period. In 1980 China was ranked 99th of all nations in terms of the percentage of global exports in high technology. By 2005 China climbed to second place in the world, first place if high technology ...

New records, names and combinations of scaly tree ferns (Cyatheaceae) in eastern Malesia

NARCIS (Netherlands)

Coritico, F.P.; Amoroso, V.B.; Lehnert, M.

2017-01-01

Several scaly tree ferns (Cyatheaceae) from eastern Malesia are transferred from Cyathea s.lat. to other genera: Alsophila roroka from Sulawesi; Alsophila lamoureuxii from New Guinea; Alsophila binayana, A. bisquamata, A. mapahuwensis, A. murkelensis, A. ohaensis, and Sphaeropteris pukuana from

Grain-size distribution of surface sediments of climbing and falling ...

Indian Academy of Sciences (India)

45

The climbing and falling dunes distributing in the wide valleys of China's Yarlung. 64. Zangbo River ...... Food and Agriculture Organization (FAO). 2006. The state of ... Global land use change, economic globalization, and. 450 the looming ...

Hold design supports learning and transfer of climbing fluency

NARCIS (Netherlands)

Orth, Dominic; Davids, Keith; Seifert, Ludovic

2014-01-01

Being a discipline with a broad range of genres, rock climbing is an activity where participants seek to generalize the skills they learn in different performance contexts. A training strategy for achieving skill transfer was explored in a group of experienced climbers. Specifically, we tested the

Climbing ability of teneral and sclerotized adult bed bugs and assessment of adhesive properties of the exoskeletal fluid using atomic force microscopy.

Directory of Open Access Journals (Sweden)

Kevin R Hinson

Full Text Available We observed that teneral adults (72 h, and sclerotized group 2 (S2 bed bugs (n = 30, height climbed = 2.64 cm at >72 h post molt. When heights from all climbing events were summed, teneral bed bugs (650.8 cm climbed differed significantly (P< 0.01 from recently sclerotized (82 cm climbed and sclerotized (group 1 = 104.6 cm climbed, group 2 = 107.8 cm climbed bed bugs. These findings suggested that the external surface of teneral bed bug exoskeletons possess an adhesive property. Using atomic force microscopy (AFM, we found that adhesion force of an exoskeletal (presumably molting fluid decreased almost five-fold from 88 to 17 nN within an hour of molting. Our findings may have implications for laboratory safety and the effectiveness of bed bug traps, barriers, and biomimetic-based adhesives.

Effect of enhanced nitrogen input on release of nutrients and nutrient availability in stands of tall fern Athyrium distentifolium

Science.gov (United States)

Tå¯Ma, Ivan; Holuib, Petr; Záhora, Jaroslav; Fiala, Karel

2010-05-01

Improved light conditions, after destruction of tree canopy, soil acidification and increased nitrogen availability, support intensive spreading of acidophilous perennial grasses and stands of tall fern (Athyrium distentifolium) on deforested sites in the Moravian-Silesian Beskydy Mts. (the Czech Republic). The aim of the study was to determine how higher inputs of nitrogen affect the release of nutrients during decomposition processes of fern litter. The experimental site was chosen on a southwest-facing slope of the Kněhyně Mt. (49o31´ N, 18o 32´E, 1170 m a.s.l.) in the Moravian-Silesin Beskydy Mts. in the Czech Republic. The area is characterized by an annual mean air temperature of 5.6 oC and annual precipitation of 1110 mm. A large fern stand was divided in four blocks (5x3 m) and on two of them higher doses of nitrogen were applied (50 kgN/ha in five doses in the course of the growing season). Similarly, mesh-bags with fresh natural litter of fern were used to determine rate of litter decomposition during one year. Samples were inserted in both nitrogen treated and untreated fern stands in autumn 2006 and 2007 collected in autumn 2007 and 2008. On the basis of litter amount estimated at the start and at the end of exposure and of actual content of minerals in original and exposed litter, the release and/or accumulation of minerals during decomposition were calculated. The availability (more or less in the case of ammonia-nitrogen) and movement of percolated nitrogen (mainly in the case of nitrate-nitrogen) was estimated in situ by the trapping of mineral N into the ion exchange resin (IER) inserted into special cover. The decomposition rate of native A. distentifolium litter was approximately the same (29-30 %) at both nitrogen availability, however the element release from decomposed litter was higher for N, P and Ca in both years and for K and Mg in the first year as well. However, decomposition rate of cellulose was two times greater in fern stands

Complete Spinal Accessory Nerve Palsy From Carrying Climbing Gear.

Science.gov (United States)

Coulter, Jess M; Warme, Winston J

2015-09-01

We report an unusual case of spinal accessory nerve palsy sustained while transporting climbing gear. Spinal accessory nerve injury is commonly a result of iatrogenic surgical trauma during lymph node excision. This particular nerve is less frequently injured by blunt trauma. The case reported here results from compression of the spinal accessory nerve for a sustained period-that is, carrying a load over the shoulder using a single nylon rope for 2.5 hours. This highlights the importance of using proper load-carrying equipment to distribute weight over a greater surface area to avoid nerve compression in the posterior triangle of the neck. The signs and symptoms of spinal accessory nerve palsy and its etiology are discussed. This report is particularly relevant to individuals involved in mountaineering and rock climbing but can be extended to anyone carrying a load with a strap over one shoulder and across the body. Copyright © 2015 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

Conservation Priorities for Tree Ferns (Cyatheaceae in Sri Lanka

Directory of Open Access Journals (Sweden)

R. H. G. Ranil

2011-09-01

Full Text Available Diversity, phytogeography and conservation status of Sri Lankan tree-ferns are discussed in this paper. The family Cyatheaceae is represented by eight taxa (seven species and one doubtful variety in Sri Lanka with a high rate of endemism of 75%. Apart from Cyathea walkerae and C. gigantea, the other species are restricted to geographically isolated areas in the country with limited population sizes. Fortunately, all Sri Lankan species of Cyathea occur within the protected areas of the wet zone. However, ex situ conservation is limited to C. walkerae and C. crinita at Botanic Gardens in Hakgala. Despite the family being listed in Annex II of CITES, its species have not yet been assessed in Sri Lanka for the Red Listing criteria. Identification of the nature and level of threat to Sri Lankan Cyathea species is therefore a major priority, followed by the monitoring of populations in situ in protected areas in the wet zone. Ex situ conservation of rare species and cultivation of Cyathea species from spores have also been identified as priority areas. A strong programme should be developed with the National Herbarium to explore little known forest patches in the wet zone to enhance our knowledge of Cyathea species in Sri Lanka. Such information will provide a strong basis for preparing a conservation and management plan for tree-ferns in the country.

Effect of habitat preference on frond life span in three Cyathea tree ferns

Science.gov (United States)

Chiu, Tzu Yun; Wang, Hsiang Hua; Lun Kuo, Yao; Kume, Tomonori

2013-04-01

It has been reported that plants living in various geographical areas had different physiological forms, as factors of microenvironment have strong impacts on physiological characters. However, the physiological characters of fronds have been scarcely reported in ferns. In this study, we investigated physiological differences in response to the habitat preference in the three tree ferns in northeast Taiwan, Cyathea lepifera, C. spinulosa, and C. podophylla, prefer to open site, edge of forest, and interior forest, respectively. The canopy openness above the individuals of C. lepifera, C. spinulosa and C. podophylla were 29.2 ± 14.10 , 7.0 ± 3.07 and 5.0 ± 2.24 %, respectively. Among three species, C. podophylla had the longest frond life span (13.0 ± 4.12 months) than the two others (C. lepifera (6.8 ± 1.29 months) and C. spinulosa (7.3 ±1.35 months). Our result supported the general patterns that shade intolerant species have a shorter leaf life span than shade tolerant species. The maximum net CO2 assimilation of C. lepifera, C. spinulosa and C. podophylla were 11.46 ± 1.34, 8.27 ± 0.69, and 6.34 ± 0.54 μmol CO2 m-2 s-1, respectively. As well, C. lepifera had the highest photosynthetic light saturation point (LSP), while C. podophylla had the lowest LSP among these three tree ferns. These suggested that C. lepifera could be more efficient for capturing and utilizing light resources under the larger canopy openness condition than the other two species. We also found that frond C : N ratio were positively correlated with frond life span among species. C. podophylla, with the longest frond life span, had the highest frond C : N ratio (22.17 ± 1.95), which was followed by C. spinulosa (18.58 ± 1.37) and C. lepifera (18.68 ± 2.63) with shorter frond life span. The results were consistent to the theory that the fronds and leaves of shade intolerant species have high photosynthetic abilities with low C : N ratio. Key words: Canopy openness, frond life span

Absorption of foliar-applied arsenic by the arsenic hyperaccumulating fern (Pteris vittata L.)

Energy Technology Data Exchange (ETDEWEB)

Bondada, Bhaskar R.; Tu, Shuxin; Ma, Lena Q

2004-10-01

The fact that heavy metals can enter various domains of the plant system through foliar pathways spurred us to explore if the fronds of the Chinese brake fern (Pteris vittata L.), a hyperaccumulator of arsenic, a carcinogenic metalloid, was proficient in absorbing arsenic in the form of sprays. The specific objective of this study was to investigate the impact of frond age, form of arsenic, and time of application on the absorption of foliar-applied arsenic by the brake fern; also examined were the effects of foliar sprays on surface ultrastructure and arsenic speciation in the frond following absorption. Foliar sprays of different arsenic concentrations (0, 50, 100, 200, and 400 ppm) were applied to young and fertile fronds. A positive linear relationship existed between arsenic concentration and absorption; the arsenic concentration of fronds increased from 50 to 200 ppm. Time-course analysis with excised pinnae indicated an initial linear increase followed by a plateau at 48 h. The young fronds with immature sori absorbed more arsenic (3100 ppm) than the fertile mature fronds (890 ppm). In the frond, the arsenic absorption was greatest in the lamina of the pinnae followed by the sori and the rachis. Applying arsenic during night (20:00-22:00 h) or afternoon (12:00-14:00 h) resulted in greater absorption of arsenic than the application in the morning (08:00-10:00 h). The arsenic absorption was greater through abaxial surfaces than through adaxial surfaces. The brake fern absorbed more arsenic when it was applied in the form of arsenite. Regardless of the form of arsenic and the surface it was applied to, arsenic occurred as arsenite, the reduced and the most toxic form of arsenic, after having been absorbed by the fronds. Scanning electron microscopy revealed no surface morphological alterations following all arsenic sprays. The study unequivocally illustrated that the Chinese brake fern absorbed foliar-applied arsenic with great efficiency. Consequently, the

Absorption of foliar-applied arsenic by the arsenic hyperaccumulating fern (Pteris vittata L.)

International Nuclear Information System (INIS)

Bondada, Bhaskar R.; Tu, Shuxin; Ma, Lena Q.

2004-01-01

The fact that heavy metals can enter various domains of the plant system through foliar pathways spurred us to explore if the fronds of the Chinese brake fern (Pteris vittata L.), a hyperaccumulator of arsenic, a carcinogenic metalloid, was proficient in absorbing arsenic in the form of sprays. The specific objective of this study was to investigate the impact of frond age, form of arsenic, and time of application on the absorption of foliar-applied arsenic by the brake fern; also examined were the effects of foliar sprays on surface ultrastructure and arsenic speciation in the frond following absorption. Foliar sprays of different arsenic concentrations (0, 50, 100, 200, and 400 ppm) were applied to young and fertile fronds. A positive linear relationship existed between arsenic concentration and absorption; the arsenic concentration of fronds increased from 50 to 200 ppm. Time-course analysis with excised pinnae indicated an initial linear increase followed by a plateau at 48 h. The young fronds with immature sori absorbed more arsenic (3100 ppm) than the fertile mature fronds (890 ppm). In the frond, the arsenic absorption was greatest in the lamina of the pinnae followed by the sori and the rachis. Applying arsenic during night (20:00-22:00 h) or afternoon (12:00-14:00 h) resulted in greater absorption of arsenic than the application in the morning (08:00-10:00 h). The arsenic absorption was greater through abaxial surfaces than through adaxial surfaces. The brake fern absorbed more arsenic when it was applied in the form of arsenite. Regardless of the form of arsenic and the surface it was applied to, arsenic occurred as arsenite, the reduced and the most toxic form of arsenic, after having been absorbed by the fronds. Scanning electron microscopy revealed no surface morphological alterations following all arsenic sprays. The study unequivocally illustrated that the Chinese brake fern absorbed foliar-applied arsenic with great efficiency. Consequently, the

Comparative Effect of Forward and Backward Stair Climbing on ...

African Journals Online (AJOL)

olagbegi

The groups were not significantly different (p> 0.05) in their cardiovascular parameters at weeks 0, 4, and 8. The FSC group had ... KEY WORDS: Stair climbing, blood pressure, cardiovascular endurance ... significantly greater metabolic responses compared to ... This was taken with the subject in sitting position, with the.

Alsophila weidenbrueckii (Cyatheaceae), a new scaly tree fern from Papua New Guinea

NARCIS (Netherlands)

Lehnert, M.

2016-01-01

The scaly tree fern Alsophila weidenbrueckii is described and illustrated as new to science. It occurs in the Bismarck range in north-eastern New Guinea at 1200–2100 m in evergreen wet mountain forest. The species reaches maturity at a comparatively old age and large size and regenerates only in

El blocao (y el bloqueo de José Díaz Fernández

Directory of Open Access Journals (Sweden)

Luis Fernando Bueno Morillas

2015-06-01

Full Text Available El blocao (1928 fue la primera novela de José Díaz Fernández. Supuso un éxito editorial insólito hasta entonces porque reunía tres características novedosas: una actitud crítica ante la guerra de Marruecos, una integración de las novedades vanguardistas en la que su autor llamó literatura de avanzada y un posicionamiento del intelectual al lado de las reivindicaciones del pueblo. Sin embargo, aunque publicó otra novela un año después (La Venus mecánica, un libro teórico en el que definía la literatura que él propugnaba y practicaba (El nuevo romanticismo y algunas narraciones breves, Díaz Fernández se bloqueó y dejó la literatura narrativa que tan buenas expectativas levantó. Analizaremos las posibles causas de ese bloqueo.

An Omni-Directional Wall-Climbing Microrobot with Magnetic Wheels Directly Integrated with Electromagnetic Micromotors

Directory of Open Access Journals (Sweden)

Xiaoning Tang

2012-04-01

Full Text Available This paper presents an omni-directional wall-climbing microrobot with magnetic wheels. The integral design with an actuator and adhesive is realized by integrating stators and rotors of an MEMS-based electromagnetic micromotor with a magnetic wheel. The omni-directional wall-climbing mechanism is designed by a set of steering gears and three standard magnetic wheels. The required torque and magnetic force for microrobot movement are derived by its static analysis. The size of the magnetic wheel is optimized, with consideration of its own design constraints, by ANSOFT and Pro/Engineer simulation so as to reduce unnecessary torque consumption under the same designed load. Related experiments demonstrate that the microrobot (diameter: 26mm; height: 16.4; mass: 7.2g; load capacity: 3g we have developed has a good wall-climbing ability and flexible mobility, and it can perform visual detection in a ferromagnetic environment.

Bird Perches Increase Forest Seeds on Puerto Rican Landslides.

Science.gov (United States)

Aaron B. Shiels; Lawrence R. Walker

2003-01-01

Landslides result in the loss of vertical vegetative structure, soil nutrients, and the soil seed bank. These losses impede timely recovery of tropical forest communities. In this study we added bird perches to six Puerto Rican landslides with three types of surfaces (bare, climbing fern, grass) in an effort to facilitate inputs of forest seeds through bird dispersal...

The scaly tree ferns (Cyatheaceae-Polypodiopsida of Brazil

Directory of Open Access Journals (Sweden)

Anna Weigand

2016-01-01

Full Text Available ABSTRACT A synopsis of all scaly tree fern species (Cyatheaceae occurring in Brazil is presented. We recognize 51 species in three genera [Sphaeropteris one species, Alsophila four species (one subspecies, two varieties, and Cyathea 45 species (one variety ] with 17 taxa being endemic to Brazil. One hybrid endemic to Brazil is recognized. Further included are five species that have not yet been recorded in Brazil, but are expected here because they are found in adjacent countries and occur literally on the border with Brazil. We present the first key covering the family for the whole territory of Brazil.

CLIMBING.CREACIÓN DE UNA MRCA DEPORTIVA

OpenAIRE

MESEGUER SANCHEZ, RAQUEL

2017-01-01

El presente TFG plantea el desarrollo de la imagen de marca de una empresa de ropa deportiva y la adaptación a sus productos, esta imagen plantea las connotaciones de fuerza y juventud y adaptable a cualquier tipo de deporte. Se estudian todos los valores implícitos en el branding y el proceso de elaboración. Meseguer Sanchez, R. (2017). CLIMBING.CREACIÓN DE UNA MRCA DEPORTIVA. http://hdl.handle.net/10251/92805 TFGM

Biomechanics and functional morphology of a climbing monocot

Science.gov (United States)

Hesse, Linnea; Wagner, Sarah T.; Neinhuis, Christoph

2016-01-01

Plants with a climbing growth habit possess unique biomechanical properties arising from adaptations to changing loading conditions connected with close attachment to mechanical supports. In monocot climbers, mechanical adaptation is restricted by the absence of a bifacial vascular cambium. Flagellaria indica was used to investigate the mechanical properties and adaptations of a monocot climber that, uniquely, attaches to the surrounding vegetation via leaf tendrils. Biomechanical methods such as three-point bending and torsion tests were used together with anatomical studies on tissue development, modification and distribution. In general, the torsional modulus was lower than the bending modulus; hence, torsional stiffness was less than flexural stiffness. Basal parts of mature stems showed the greatest stiffness while that of more apical stem segments levelled off. Mechanical properties were modulated via tissue maturation processes mainly affecting the peripheral region of the stem. Peripheral vascular bundles showed a reduction in the amount of conducting tissue while the proportion and density of the bundle sheath increased. Furthermore, adjacent bundle sheaths merged resulting in a dense ring of fibrous tissue. Although F. indica lacks secondary cambial growth, the climbing habit is facilitated by a complex interaction of tissue maturation and attachment. PMID:26819259

Modeling and analysis of a meso-hydraulic climbing robot with artificial muscle actuation.

Science.gov (United States)

Chapman, Edward M; Jenkins, Tyler E; Bryant, Matthew

2017-07-10

This paper presents a fully coupled electro-hydraulic model of a bio-inspired climbing robot actuated by fluidic artificial muscles (FAMs). This analysis expands upon previous FAM literature by considering not only the force and contraction characteristics of the actuator, but the complete hydraulic and electromechanical circuits as well as the dynamics of the climbing robot. This analysis allows modeling of the time-varying applied pressure, electrical current, and actuator contraction for accurate prediction of the robot motion, energy consumption, and mechanical work output. The developed model is first validated against mechanical and electrical data collected from a proof-of-concept prototype robot. The model is then employed to study the system-level sensitivities of the robot locomotion efficiency and average climbing speed to several design and operating parameters. The results of this analysis demonstrate that considering only the transduction efficiency of the FAM actuators is insufficient to maximize the efficiency of the complete robot, and that a holistic approach can lead to significant improvements in performance. © 2017 IOP Publishing Ltd.

Watch Out for Your Neighbor: Climbing onto Shrubs Is Related to Risk of Cannibalism in the Scorpion Buthus cf. occitanus.

Science.gov (United States)

Sánchez-Piñero, Francisco; Urbano-Tenorio, Fernando

The distribution and behavior of foraging animals usually imply a balance between resource availability and predation risk. In some predators such as scorpions, cannibalism constitutes an important mortality factor determining their ecology and behavior. Climbing on vegetation by scorpions has been related both to prey availability and to predation (cannibalism) risk. We tested different hypotheses proposed to explain climbing on vegetation by scorpions. We analyzed shrub climbing in Buthus cf. occitanus with regard to the following: a) better suitability of prey size for scorpions foraging on shrubs than on the ground, b) selection of shrub species with higher prey load, c) seasonal variations in prey availability on shrubs, and d) whether or not cannibalism risk on the ground increases the frequency of shrub climbing. Prey availability on shrubs was compared by estimating prey abundance in sticky traps placed in shrubs. A prey sample from shrubs was measured to compare prey size. Scorpions were sampled in six plots (50 m x 10 m) to estimate the proportion of individuals climbing on shrubs. Size difference and distance between individuals and their closest scorpion neighbor were measured to assess cannibalism risk. The results showed that mean prey size was two-fold larger on the ground. Selection of particular shrub species was not related to prey availability. Seasonal variations in the number of scorpions on shrubs were related to the number of active scorpions, but not with fluctuations in prey availability. Size differences between a scorpion and its nearest neighbor were positively related with a higher probability for a scorpion to climb onto a shrub when at a disadvantage, but distance was not significantly related. These results do not support hypotheses explaining shrub climbing based on resource availability. By contrast, our results provide evidence that shrub climbing is related to cannibalism risk.

Innovative gait robot for the repetitive practice of floor walking and stair climbing up and down in stroke patients.

Science.gov (United States)

Hesse, Stefan; Waldner, Andreas; Tomelleri, Christopher

2010-06-28

Stair climbing up and down is an essential part of everyday's mobility. To enable wheelchair-dependent patients the repetitive practice of this task, a novel gait robot, G-EO-Systems (EO, Lat: I walk), based on the end-effector principle, has been designed. The trajectories of the foot plates are freely programmable enabling not only the practice of simulated floor walking but also stair climbing up and down. The article intended to compare lower limb muscle activation patterns of hemiparetic subjects during real floor walking and stairs climbing up, and during the corresponding simulated conditions on the machine, and secondly to demonstrate gait improvement on single case after training on the machine. The muscle activation pattern of seven lower limb muscles of six hemiparetic patients during free and simulated walking on the floor and stair climbing was measured via dynamic electromyography. A non-ambulatory, sub-acute stroke patient additionally trained on the G-EO-Systems every workday for five weeks. The muscle activation patterns were comparable during the real and simulated conditions, both on the floor and during stair climbing up. Minor differences, concerning the real and simulated floor walking conditions, were a delayed (prolonged) onset (duration) of the thigh muscle activation on the machine across all subjects. Concerning stair climbing conditions, the shank muscle activation was more phasic and timely correct in selected patients on the device. The severely affected subject regained walking and stair climbing ability. The G-EO-Systems is an interesting new option in gait rehabilitation after stroke. The lower limb muscle activation patterns were comparable, a training thus feasible, and the positive case report warrants further clinical studies.

The effects of climbing cages on behaviour of female mink during the lactation period

DEFF Research Database (Denmark)

Lidfors, L.; Axelsson, H.; Loberg, J.

2012-01-01

=46) or standard cages (2.550 cm², n=44). Behavioural observations were made four weeks before birth until kits were nine weeks old with one-zero sampling during two hours before feeding. During week 1-4 after females had given birth they were mostly recorded in the nest box and there were......The aim was to investigate if there were differences in behaviour of female mink when kept in a climbing cage compared with a standard cage during the lactation period. The study was carried out on 90 mink of the colour type "black cross". Females were housed in either climbing cages (4.350 cm², n...... no differences between cage types. Week 5-8 after giving birth females in climbing cages were less in the nest box, less active out in the cage and had fewer abnormal behaviours, but were on the platforms and more inactive out in the cage. In the bottom cage females were more often walking, grooming and inactive...

The CLIMB Geoportal - A web-based dissemination and documentation platform for hydrological modelling data

Science.gov (United States)

Blaschek, Michael; Gerken, Daniel; Ludwig, Ralf; Duttmann, Rainer

2015-04-01

Geoportals are important elements of spatial data infrastructures (SDIs) that are strongly based on GIS-related web services. These services are basically meant for distributing, documenting and visualizing (spatial) data in a standardized manner; an important but challenging task especially in large scientific projects with a high number of data suppliers and producers from various countries. This presentation focuses on introducing the free and open-source based geoportal solution developed within the research project CLIMB (Climate Induced Changes on the Hydrology of Mediterranean Basins, www.climb-fp7.eu) that serves as the central platform for interchanging project-related spatial data and information. In this collaboration, financed by the EU-FP7-framework and coordinated at the LMU Munich, 21 partner institutions from nine European and non-European countries were involved. The CLIMB Geoportal (lgi-climbsrv.geographie.uni-kiel.de) stores and provides spatially distributed data about the current state and future changes of the hydrological conditions within the seven CLIMB test sites around the Mediterranean. Hydrological modelling outcome - validated by the CLIMB partners - is offered to the public in forms of Web Map Services (WMS), whereas downloading the underlying data itself through Web Coverage Services (WCS) is possible for registered users only. A selection of common indicators such as discharge, drought index as well as uncertainty measures including their changes over time were used in different spatial resolution. Besides map information, the portal enables the graphical display of time series of selected variables calculated by the individual models applied within the CLIMB-project. The implementation of the CLIMB Geoportal is finally based on version 2.0c5 of the open source geospatial content management system GeoNode. It includes a GeoServer instance for providing the OGC-compliant web services and comes with a metadata catalog (pycsw) as well

Novel fungi from an ancient niche: lachnoid and chalara-like fungi on ferns

NARCIS (Netherlands)

Guatimosim, E.; Schwartsburd, P. B.; Crous, P. W.; Barreto, R. W.

2016-01-01

A survey was conducted in Brazil to collect fungi on ferns. Based on morphology and inferred phylogeny from DNA sequences of two loci, namely the internal transcribed spacer (ITS) regions and the large subunit nuclear ribosomal RNA gene (LSU), several species belonging to chalara-like genera and

Climbing fibers predict movement kinematics and performance errors.

Science.gov (United States)

Streng, Martha L; Popa, Laurentiu S; Ebner, Timothy J

2017-09-01

Requisite for understanding cerebellar function is a complete characterization of the signals provided by complex spike (CS) discharge of Purkinje cells, the output neurons of the cerebellar cortex. Numerous studies have provided insights into CS function, with the most predominant view being that they are evoked by error events. However, several reports suggest that CSs encode other aspects of movements and do not always respond to errors or unexpected perturbations. Here, we evaluated CS firing during a pseudo-random manual tracking task in the monkey ( Macaca mulatta ). This task provides extensive coverage of the work space and relative independence of movement parameters, delivering a robust data set to assess the signals that activate climbing fibers. Using reverse correlation, we determined feedforward and feedback CSs firing probability maps with position, velocity, and acceleration, as well as position error, a measure of tracking performance. The direction and magnitude of the CS modulation were quantified using linear regression analysis. The major findings are that CSs significantly encode all three kinematic parameters and position error, with acceleration modulation particularly common. The modulation is not related to "events," either for position error or kinematics. Instead, CSs are spatially tuned and provide a linear representation of each parameter evaluated. The CS modulation is largely predictive. Similar analyses show that the simple spike firing is modulated by the same parameters as the CSs. Therefore, CSs carry a broader array of signals than previously described and argue for climbing fiber input having a prominent role in online motor control. NEW & NOTEWORTHY This article demonstrates that complex spike (CS) discharge of cerebellar Purkinje cells encodes multiple parameters of movement, including motor errors and kinematics. The CS firing is not driven by error or kinematic events; instead it provides a linear representation of each

Rates of molecular evolution in tree ferns are associated with body size, environmental temperature, and biological productivity.

Science.gov (United States)

Barrera-Redondo, Josué; Ramírez-Barahona, Santiago; Eguiarte, Luis E

2018-05-01

Variation in rates of molecular evolution (heterotachy) is a common phenomenon among plants. Although multiple theoretical models have been proposed, fundamental questions remain regarding the combined effects of ecological and morphological traits on rate heterogeneity. Here, we used tree ferns to explore the correlation between rates of molecular evolution in chloroplast DNA sequences and several morphological and environmental factors within a Bayesian framework. We revealed direct and indirect effects of body size, biological productivity, and temperature on substitution rates, where smaller tree ferns living in warmer and less productive environments tend to have faster rates of molecular evolution. In addition, we found that variation in the ratio of nonsynonymous to synonymous substitution rates (dN/dS) in the chloroplast rbcL gene was significantly correlated with ecological and morphological variables. Heterotachy in tree ferns may be influenced by effective population size associated with variation in body size and productivity. Macroevolutionary hypotheses should go beyond explaining heterotachy in terms of mutation rates and instead, should integrate population-level factors to better understand the processes affecting the tempo of evolution at the molecular level. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.

A comparison of alpha and beta diversity patterns of ferns, bryophytes and macrolichens in tropical montane forests of southern Ecuador

OpenAIRE

Mandl, N A; Lehnert, M; Kessler, M; Gradstein, S R

2010-01-01

We present a first comparison of patterns of alpha and beta diversity of ferns, mosses, liverworts and macrolichens in neotropical montane rainforests, and explore the question whether specific taxa may be used as surrogates for others. In three localities in southern Ecuador, we surveyed terrestrial and epiphytic species assemblages in ridge and slope forests in 28 plots of 400 m² each. The epiphytic habitat was significantly richer in ferns, liverworts, and macrolichens than the terrestrial...

Grass or fern competition reduce growth and survival of planted tree seedlings

Science.gov (United States)

Larry H. McCormick; Todd W. Bowersox

1997-01-01

Bareroot seedlings of northern red oak, white ash, yellow-poplar and white pine were planted into herbaceous communities at three forested sites in central Pennsylvania that were clearcut 0 to 1 year earlier. Seedlings were grown 4 years in the presence and absence of either an established grass or hay-scented fern community. Survival and height growth were measured...

Population biology of two rare fern species: long-life and long-lasting stability

Czech Academy of Sciences Publication Activity Database

Bucharová, Anna; Münzbergová, Z.; Tájek, P.

2010-01-01

Roč. 97, č. 8 (2010), s. 1260-1271 ISSN 0002-9122 R&D Projects: GA MŽP SP/2D4/112/08 Institutional research plan: CEZ:AV0Z60050516 Keywords : ferns * life cycle * naturally rare species Subject RIV: EF - Botanics Impact factor: 3.052, year: 2010

Effect of pH on lead removal from water using tree fern as the sorbent.

Science.gov (United States)

Ho, Yuh-Shan

2005-07-01

The sorption of lead from water onto an agricultural by-product, tree fern, was examined as a function of pH. The sorption processes were carried out using an agitated and baffled system. Pseudo-second-order kinetic analyses were performed to determine the rate constant of sorption, the equilibrium sorption capacity, and the initial sorption rate. Application of the pseudo-second-order kinetics model produced very high coefficients of determination. Results showed the efficiency of tree fern as a sorbent for lead. The optimum pH for lead removal was between 4 and 7, with pH 4.9 resulting in better lead removal. Ion exchange occurred in the initial reaction period. In addition, a relation between the change in the solution hydrogen ion concentration and equilibrium capacity was developed and is presented.

Psychological profile of Turkish rock climbers: an examination of climbing experience and route difficulty.

Science.gov (United States)

Aşçi, F Hülya; Demirhan, Giyasettin; Dinç, S Cem

2007-06-01

The purpose of this study was to examine sensation seeking, physical self-perception, and intrinsic and extrinsic motives of rock climbers and to compare these psychological constructs with respect to their years of climbing experience and the difficulty of their climbing routes. 64 climbers (M age=29.1 yr., SD=6.4) voluntarily participated in this study. The Arnett Inventory of Sensation Seeking (AISS), Physical Self-Description Questionnaire (PSDQ), and Sport Motivation Scale (SMS) were administered to the rock climbers. Analysis indicated that the mean score of rock climbers on the Novelty subscale of the Sensation Seeking Scale was 33.9 (SD= 3.6) and mean value on the Intensity subscale was 29.2 (SD=5.2). The mean scores of rock climbers on the PSDQ ranged between 3.9 (SD= 1.0, Physical Activity) and 5.1 (SD= 1.1, Body Fat). Descriptive analysis indicated that the highest mean score of rock climbers on the SMS was obtained in Intrinsic motivation to Experience Stimulation (5.7, SD= 0.9). The independent sample t test showed no significant differences in sensation seeking, physical self-perception, and sport motivation with regard to years of climbing experience and route difficulty (p>.05). It may be concluded that sensation seeking in climbers is high, and they have internal motivational orientation and positive physical self-perception; their competence in climbing has no obvious relationship to these variables.

Innovative gait robot for the repetitive practice of floor walking and stair climbing up and down in stroke patients

Directory of Open Access Journals (Sweden)

Waldner Andreas

2010-06-01

Full Text Available Abstract Background Stair climbing up and down is an essential part of everyday's mobility. To enable wheelchair-dependent patients the repetitive practice of this task, a novel gait robot, G-EO-Systems (EO, Lat: I walk, based on the end-effector principle, has been designed. The trajectories of the foot plates are freely programmable enabling not only the practice of simulated floor walking but also stair climbing up and down. The article intended to compare lower limb muscle activation patterns of hemiparetic subjects during real floor walking and stairs climbing up, and during the corresponding simulated conditions on the machine, and secondly to demonstrate gait improvement on single case after training on the machine. Methods The muscle activation pattern of seven lower limb muscles of six hemiparetic patients during free and simulated walking on the floor and stair climbing was measured via dynamic electromyography. A non-ambulatory, sub-acute stroke patient additionally trained on the G-EO-Systems every workday for five weeks. Results The muscle activation patterns were comparable during the real and simulated conditions, both on the floor and during stair climbing up. Minor differences, concerning the real and simulated floor walking conditions, were a delayed (prolonged onset (duration of the thigh muscle activation on the machine across all subjects. Concerning stair climbing conditions, the shank muscle activation was more phasic and timely correct in selected patients on the device. The severely affected subject regained walking and stair climbing ability. Conclusions The G-EO-Systems is an interesting new option in gait rehabilitation after stroke. The lower limb muscle activation patterns were comparable, a training thus feasible, and the positive case report warrants further clinical studies.

Autobiografía y memoria en el diario de viajes del VI Conde de Fernán Núñez = Autobiography and Memory in the Travel Diary of the VI Count of Fernán Núñez

Directory of Open Access Journals (Sweden)

Carolina Blutrach

2016-12-01

Full Text Available ResumenEl viaje fue una constante en la vida de don Carlos José Gutiérrez de los Ríos, VI conde de Fernán Núñez (1742-1795. A través de ellos pudo cumplir con su servicio al rey y con sus responsabilidades como cabeza del linaje. Asimismo pudo completar su formación y satisfacer anhelos más personales. De todos sus viajes, los realizados dentro y fuera de España, guardó memoria escrita en un diario de viajes, un documento que, en formato manuscrito, se conservó en su archivo familiar. En un periodo cronológico en el que el viaje y su relato adquirieron especial protagonismo, este trabajo analiza el papel que el viaje jugó en la vida y memoria del VI conde de Fernán Núñez y su impronta dentro del linaje.AbstractTravelling had a constant presence in the life of don Carlos José Gutiérrez de los Ríos, VI Count of Fernán Núñez (1742-1795. Through them he could fulfil his service to the king and his responsibilities as head of the lineage. He could also complete his training and meet more personal yearnings. Of all his travels, the ones he made in and out of Spain, he kept a record in his Travel Diary, which was preserved as a manuscript in the family archive. In a period in which travelling and its written memory gained special prominence, this paper analyses the role it played in the life and memory of the VI Count of Fernán Núñez and its mark within the lineage.

To be active through indoor-climbing: an exploratory feasibility study in a group of children with cerebral palsy and typically developing children

DEFF Research Database (Denmark)

Christensen, Mark Schram; Jensen, Thor; Voigt, Camilla B.

2017-01-01

beneficial effects of climbing activities in populations with functional and/or cognitive challenges. The aim of this study was therefore to test the feasibility of an intensive 3 weeks indoor-climbing training program in children with CP and typically developing (TD) peers. In addition we evaluated possible...... indoor-climbing training sessions, and climbing abilities were measured. The participants were tested in a series of physiological, psychological and cognitive tests: two times prior to and one time following the training in order to explore possible effects of the intervention.Results: The children...... in cognitive abilities or psychological well-being in any of the groups.Conclusions: These findings show that it is possible to use climbing as means to make children with CP physically active. The improved motor abilities obtained through the training is likely reflected by increased synchronization between...

Synthesizing research and education: Ecology and genetics of independent fern gametophytes and teaching science inquiry and content through simulations

Science.gov (United States)

Duffy, Aaron M.

Two of the main areas of focus in university academics are research and education. The mission statements of Utah State University and the Department of Biology emphasize both areas, as do the requirements of funding agencies. I attempted to integrate research and education by using tools that I developed to support and inform my biological research projects to teach science. Ferns have a life cycle with alternating haploid and diploid life stages, both of which are free-living and potentially long-lived. The haploid gametophytes of some ferns reproduce asexually and may have different environmental requirements than the diploid sporophytes, so it is possible for populations of gametophytes to exist without sporophytes. This dissertation includes a description of surveys for Hymenophyllum wrightii, a fern with independent gametophytes in the Pacific Northwest, and improves our understanding of the range, distribution, and habitat requirements of these plants which were previously assumed to be rare. It also describes an attempt to explore the population genetics of gametophytes of Crepidomanes intricatum, a widespread fern in the Appalachian Mountains for which no sporophytes have ever been found. To help visualize evolutionary processes in independent gametophyte populations I developed the Virtual Population Genetics Simulator (VPGsim) to simulate populations of ferns in a 3-dimensional environment. This dissertation includes a description of VPGsim, a learning module using it to teach undergraduate genetics, and a study demonstrating its effectiveness at improving students' understanding of science content and confidence in their ability to perform science inquiry. That simulation tool led to a collaboration to find other ways to teach science with simulations, and to the development of a Virtual Plant Community simulator (VPCsim) for teaching middle school students about the effects of the environment and human impacts on living organisms. This dissertation

Test Area B-75 Final Range Environmental Assessment (REA), Revision 1

Science.gov (United States)

2010-08-01

impacts to Eglin ecosystems. Some of the main invasive non-native species of concern are Chinese tallow, cogon grass , Japanese climbing fern...lotor Saw Grass Cladium jamaicensis Florida Black Bear Ursus americanus floridanus Cattail Typha domingensis Sherman’s Fox Squirrel Sciuris niger...Cont’d Yellow Indian Grass Sorghastrum nutans Flycatchers Tyrannidae spp. Purple Lovegrass Eragrostis spectabilis Cotton Mouse Peromyscus gossypinus

Climbing walls as multitasking sites of geo(morpho)logical interests: Italian examples from the Western Alps and Sardinia

Science.gov (United States)

Bollati, Irene; Fossati, Maria; Panizza, Valeria; Pelfini, Manuela; Zanoletti, Enrico; Zucali, Michele

2015-04-01

Geosites and in particular geomorphosites have been recently more and more used as base for educational activities in Earth Sciences and to enhance the geodiversity of a territory. Their attributes acquire a greater value and become especially appreciable when associated with field and outdoor activities. Frequently rock walls represent key sites for geological and gemorphological researches due to the wide outcrops of rocks where mineralogical composition and structures are very evident as well as landforms deriving from the modeling of outcrops surfaces. Where the rock walls are equipped for climbing activities they may be considered open-air laboratories useful to get in touch with the different features of rocks that condition progression on climbing routes. Due to these two aspects, geohistorical importance and educational exemplarity contribute to the increase of the scientific value and, as a consequence, of the global value of these sites as geosites. Geomorphosites from climbing sites allow to realize educational projects with different goals: 1) Recent researches in the Western Italian Alps have been conducted to make a census of climbing rock cliffs along the Ossola Valley (Verbanio-Cusio-Ossola Province, Italy) and to operate a choice of the ones characterized by high educational value (considering easy accessibility, grades for experts and beginners and the good exposition of rock features), representativeness, geohistorical importance, high cultural and socio-economic values, in order to propose an educational project addressed to students of an Italian secondary school aimed at introducing the three great families of rocks (magmatic, metamorphic and sedimentary); 2) The Eclogitic Micaschist Complex of the Austroalpine Domain (Montestrutto climbing wall, Turin Province, Italy) has been investigated in order to i) reconstruct the deformation stages at local scales along the sport climbing wall and the relationships between geological elements and

A review of the fern genus Hypolepis (Dennstardtiaceae) in the Malesian and Pacific regions

NARCIS (Netherlands)

Brownsey, P.J.

1987-01-01

Fourteen species and one subspecies of the fern genus Hypolepis Bernh. are recognised in the Malesian and Pacific regions, excluding Australia and New Zealand. Three species, H. hawaiiensis, H. malesiana and H. scabristipes, and one subspecies, H. elegans subsp. carolinensis, are described for the

Air humidity as key determinant of morphogenesis and productivity of the rare temperate woodland fern Polystichum braunii.

Science.gov (United States)

Schwerbrock, R; Leuschner, C

2016-07-01

(1) Most ferns are restricted to moist and shady habitats, but it is not known whether soil moisture or atmospheric water status are decisive limiting factors, or if both are equally important. (2) Using the rare temperate woodland fern Polystichum braunii, we conducted a three-factorial climate chamber experiment (soil moisture (SM) × air humidity (RH) × air temperature (T)) to test the hypotheses that: (i) atmospheric water status (RH) exerts a similarly large influence on the fern's biology as soil moisture, and (ii) both a reduction in RH and an increase in air temperature reduce vigour and growth. (3) Nine of 11 morphological, physiological and growth-related traits were significantly influenced by an increase in RH from 65% to 95%, leading to higher leaf conductance, increased above- and belowground productivity, higher fertility, more epidermal trichomes and fewer leaf deformities under high air humidity. In contrast, soil moisture variation (from 66% to 70% in the moist to ca. 42% in the dry treatment) influenced only one trait (specific leaf area), and temperature variation (15 °C versus 19 °C during daytime) only three traits (leaf conductance, root/shoot ratio, specific leaf area); RH was the only factor affecting productivity. (4) This study is the first experimental proof for a soil moisture-independent air humidity effect on the growth of terrestrial woodland ferns. P. braunii appears to be an air humidity hygrophyte that, whithin the range of realistic environmental conditions set in this study, suffers more from a reduction in RH than in soil moisture. A climate warming-related increase in summer temperatures, however, seems not to directly threaten this endangered species. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

The effect of climbing Mount Everest on spleen contraction and increase in hemoglobin concentration during breath holding and exercise.

Science.gov (United States)

Engan, Harald K; Lodin-Sundström, Angelica; Schagatay, Fanny; Schagatay, Erika

2014-04-01

Release of stored red blood cells resulting from spleen contraction improves human performance in various hypoxic situations. This study determined spleen volume resulting from two contraction-evoking stimuli: breath holding and exercise before and after altitude acclimatization during a Mount Everest ascent (8848 m). Eight climbers performed the following protocol before and after the climb: 5 min ambient air respiration at 1370 m during rest, 20 min oxygen respiration, 20 min ambient air respiration at 1370 m, three maximal-effort breath holds spaced by 2 min, 10 min ambient air respiration, 5 min of cycling at 100 W, and finally 10 min ambient air respiration. We measured spleen volume by ultrasound and capillary hemoglobin (HB) concentration after each exposure, and heart rate (HR) and arterial oxygen saturation (Sao2) continuously. Mean (SD) baseline spleen volume was unchanged at 213 (101) mL before and 206 (52) mL after the climb. Before the climb, spleen volume was reduced to 184 (83) mL after three breath holds, and after the climb three breath holds resulted in a spleen volume of 132 (26) mL (p=0.032). After exercise, the preclimb spleen volume was 186 (89) mL vs. 112 (389) mL) after the climb (p=0.003). Breath hold duration and cardiovascular responses were unchanged after the climb. We concluded that spleen contraction may be enhanced by altitude acclimatization, probably reflecting both the acclimatization to chronic hypoxic exposure and acute hypoxia during physical work.

Leaf hydraulic capacity in ferns, conifers and angiosperms: impacts on photosynthetic maxima.

Science.gov (United States)

Brodribb, Tim J; Holbrook, N Michele; Zwieniecki, Maciej A; Palma, Beatriz

2005-03-01

* The hydraulic plumbing of vascular plant leaves varies considerably between major plant groups both in the spatial organization of veins, as well as their anatomical structure. * Five conifers, three ferns and 12 angiosperm trees were selected from tropical and temperate forests to investigate whether the profound differences in foliar morphology of these groups lead to correspondingly profound differences in leaf hydraulic efficiency. * We found that angiosperm leaves spanned a range of leaf hydraulic conductance from 3.9 to 36 mmol m2 s-1 MPa-1, whereas ferns (5.9-11.4 mmol m-2 s-1 MPa-1) and conifers (1.6-9.0 mmol m-2 s-1 MPa-1) were uniformly less conductive to liquid water. Leaf hydraulic conductance (Kleaf) correlated strongly with stomatal conductance indicating an internal leaf-level regulation of liquid and vapour conductances. Photosynthetic capacity also increased with Kleaf, however, it became saturated at values of Kleaf over 20 mmol m-2 s-1 MPa-1. * The data suggest that vessels in the leaves of the angiosperms studied provide them with the flexibility to produce highly conductive leaves with correspondingly high photosynthetic capacities relative to tracheid-bearing species.

Mutation induction of blechnum gibium a fern species through in vitro propagation

International Nuclear Information System (INIS)

Azhar Mohamad; Amran Abd Halim; Rusli Ibrahim

2002-01-01

Blechnum gibum is a fern with beutiful symmetry and unique palm-like appearance. Mutation induction is an alternative way to increase its variability in characteristics. Information on the radiosensitivity test is an important factor in deciding the approach to be taken for genetic changes of the fern in mutation breeding. Plantlets of B. gibum were irradiated with doses of 0, 10, 20, 40, 60, 80, 100 and 150 Gy using a gamma cell with a 60 Co source at dose rate of 0.25 Gy s -1 . . Irradiated plantlets were cultured on semi solid modified hormone free Murashige and Skoog (MS) media and incubated at 24 degree C with a photoperiod of 16 hours (3500 lux). Radiosensitivity was assessed by the survival rate 7 weeks after the treatment. Increasing gamma ray doses caused a reduction of survival rate as well as the number of fronds produced per plantlet. LD 50 for B. gibum was 54 Gy as estimated from the dose rate vs survival curve. Regenerated plantlets from treated plantlets showed a stunted and slow recovery growth especially for higher doses as compared to control plantlets. (Author)

High gene flow in epiphytic ferns despite habitat loss and fragmentation

OpenAIRE

Winkler, Manuela; Koch, Marcus; Hietz, Peter

2011-01-01

Tropical montane forests suffer from increasing fragmentation and replacement by other types of land-use such as coffee plantations. These processes are known to affect gene flow and genetic structure of plant populations. Epiphytes are particularly vulnerable because they depend on their supporting trees for their entire life-cycle. We compared population genetic structure and genetic diversity derived from AFLP markers of two epiphytic fern species differing in their ability to colonize sec...

Modelling phytoremediation by the hyperaccumulating fern, Pteris vittata, of soils historically contaminated with arsenic.

Science.gov (United States)

Shelmerdine, Paula A; Black, Colin R; McGrath, Steve P; Young, Scott D

2009-05-01

Pteris vittata plants were grown on twenty-one UK soils contaminated with arsenic (As) from a wide range of natural and anthropogenic sources. Arsenic concentration was measured in fern fronds, soil and soil pore water collected with Rhizon samplers. Isotopically exchangeable soil arsenate was determined by equilibration with (73)As(V). Removal of As from the 21 soils by three sequential crops of P. vittata ranged between 0.1 and 13% of total soil As. Ferns grown on a soil subjected to long-term sewage sludge application showed reduced uptake of As because of high available phosphate concentrations. A combined solubility-uptake model was parameterised to enable prediction of phytoremediation success from estimates of soil As, 'As-lability' and soil pH. The model was used to demonstrate the remediation potential of P. vittata under different soil conditions and with contrasting assumptions regarding re-supply of the labile As pool from unavailable forms.

Using a Microscale Approach to Rapidly Separate and Characterize Three Photosynthetic Pigment Species from Fern

Science.gov (United States)

Ayudhya, Theppawut Israsena Na; Posey, Frederick T.; Tyus, Jessica C.; Dingra, Nin N.

2015-01-01

A rapid separation of three photosynthetic pigments (chlorophyll "a" and "b" and xanthophyll) from fern ("Polystichum acrostichoides") is described using microscale solvent extraction and traditional thin layer chromatography that minimizes use of harmful chemicals and lengthy procedures. The experiment introduces…

Ask Dr. Sue: Tree Climbing and Care of Sand Play Areas.

Science.gov (United States)

Aronson, Susan S.

1993-01-01

Discusses safety aspects of tree climbing and the use of sand in outdoor play areas at day care centers. Specifies ways to prune trees so that they are unclimbable and methods for maintaining sand areas. Includes a recipe for sand disinfectant. (MDM)

Umbrella Wheel - a stair-climbing and obstacle-handling wheel design concept

DEFF Research Database (Denmark)

Iversen, Simon; Jouffroy, Jerome

2017-01-01

This paper proposes a new design for stair-climbing using a wheel that can split into segments and walk up stairs or surmount other obstacles often found where humans traverse, while still being able to retain a perfectly round shape for traveling on smooth ground. Using this change of configurat......This paper proposes a new design for stair-climbing using a wheel that can split into segments and walk up stairs or surmount other obstacles often found where humans traverse, while still being able to retain a perfectly round shape for traveling on smooth ground. Using this change...... of configuration, staircases with a wide range of dimensions can be covered efficiently and safely. The design, named Umbrella Wheel, can consist of as many wheel segments as desired, and as few as two. A smaller or higher number of wheel segments has advantages and disadvantages depending on the specific...

relative performance of staking techniques on yield of climbing bean

African Journals Online (AJOL)

ACSS

Common bean (Phaseolus vulgaris L.) is an important staple grain legume in the Great Lakes Region of Africa. In addition, it is a major source of proteins, energy and micro-nutrients (e.g. Fe and Zn), especially for smallholder farmers. The climbing bean is particularly more productive, an efficient land user and tolerant to ...

Non-linear growth in tree ferns, Dicksonia antarctica and Cyathea australis

OpenAIRE

Blair, David P.; Blanchard, Wade; Banks, Sam C.; Lindenmayer, David B.

2017-01-01

Tree ferns are an important structural component of forests in many countries. However, because their regeneration is often unrelated to major disturbances, their age is often difficult to determine. In addition, rates of growth may not be uniform, which further complicates attempts to determine their age. In this study, we measured 5 years of growth of Cyathea australis and Dicksonia antarctica after a large wildfire in 2009 in south-eastern Australia. We found growth rates of these two spec...

Test Area B-70 Final Range Environmental Assessment, Revision 1

Science.gov (United States)

2009-06-01

environmental impacts to Eglin ecosystems. Some of the main invasive non-native species of concern are Chinese tallow, cogon grass , Japanese climbing fern...2003a). Typical plant species include St. John’s Wort (Hypericum brachyphyllum) around the margins with spikerush (Eleocharis spp.), yellow-eyed grass ...Karst Pond Yellow-eyed Grass Xyris longisepala SE -- Pineland Hoary Pea Tephrosia mohrii ST -- Pineland Wild Indigo Baptista calycosa var villosa ST

Arsenic accumulation by the aquatic fern Azolla: Comparison of arsenate uptake, speciation and efflux by A. caroliniana and A. filiculoides

Energy Technology Data Exchange (ETDEWEB)

Zhang Xin [State Key Lab of Urban and ONAL Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Lin Aijun [Department of Environmental Science and Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Zhao Fangjie [Soil Science Department, Rothamsted Research, Hertfordshire AL5 2JQ (United Kingdom); Xu Guozhong [Agricultural Ecology Institute, Fujian Academy of Agricultural Sciences, Fuzhou 350013 (China); Duan Guilan [State Key Lab of Urban and ONAL Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Zhu Yongguan [State Key Lab of Urban and ONAL Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361003 (China)], E-mail: ygzhu@rcees.ac.cn

2008-12-15

This study investigates As accumulation and tolerance of the aquatic fern Azolla. Fifty strains of Azolla showed a large variation in As accumulation. The highest- and lowest-accumulating ferns among the 50 strains were chosen for further investigations. Azolla caroliniana accumulated two times more As than Azolla filiculoides owing to a higher influx velocity for arsenate. A. filiculoides was more resistant to external arsenate due to a lower uptake. Both strains showed a similar degree of tolerance to internal As. Arsenate and arsenite were the dominant As species in both Azolla strains, with methlyated As species accounting for <5% of the total As. A. filiculoides had a higher proportion of arsenite than A. caroliniana. Both strains effluxed more arsenate than arsenite, and the amount of As efflux was proportional to the amount of As accumulation. The potential of growing Azolla in paddy fields to reduce As transfer from soil and water to rice should be further evaluated. - Arsenic accumulation and efflux differ between strains of the aquatic fern Azolla.

Arsenic accumulation by the aquatic fern Azolla: Comparison of arsenate uptake, speciation and efflux by A. caroliniana and A. filiculoides

International Nuclear Information System (INIS)

Zhang Xin; Lin Aijun; Zhao Fangjie; Xu Guozhong; Duan Guilan; Zhu Yongguan

2008-01-01

This study investigates As accumulation and tolerance of the aquatic fern Azolla. Fifty strains of Azolla showed a large variation in As accumulation. The highest- and lowest-accumulating ferns among the 50 strains were chosen for further investigations. Azolla caroliniana accumulated two times more As than Azolla filiculoides owing to a higher influx velocity for arsenate. A. filiculoides was more resistant to external arsenate due to a lower uptake. Both strains showed a similar degree of tolerance to internal As. Arsenate and arsenite were the dominant As species in both Azolla strains, with methlyated As species accounting for <5% of the total As. A. filiculoides had a higher proportion of arsenite than A. caroliniana. Both strains effluxed more arsenate than arsenite, and the amount of As efflux was proportional to the amount of As accumulation. The potential of growing Azolla in paddy fields to reduce As transfer from soil and water to rice should be further evaluated. - Arsenic accumulation and efflux differ between strains of the aquatic fern Azolla

Distributed mechatronics controller for modular wall climbing robot

CSIR Research Space (South Africa)

Tlale, NS

2006-07-01

Full Text Available - climbing robot for inspection in nuclear power plants.”, Proc. IEEE Int. Conf. on Robotics and Automation, pp. 409-1414. (Chen 2001) Chen, D-. J., 2001, “Architecture for Systematic Development of Mechatronics Software Systems”, Licentiate Thesis... provide a more cost effective solution to the problem (Luk et al 1991). Such robots are termed service robots by the International Service Robot Association (ISRA) (Pransky 1996). They are defined as machines that sense, think, and act to benefit (or...

Present, past and future of the European rock fern Asplenium fontanum: combining distribution modelling and population genetics to study the effect of climate change on geographic range and genetic diversity.

Science.gov (United States)

Bystriakova, Nadia; Ansell, Stephen W; Russell, Stephen J; Grundmann, Michael; Vogel, Johannes C; Schneider, Harald

2014-02-01

Climate change is expected to alter the geographic range of many plant species dramatically. Predicting this response will be critical to managing the conservation of plant resources and the effects of invasive species. The aim of this study was to predict the response of temperate homosporous ferns to climate change. Genetic diversity and changes in distribution range were inferred for the diploid rock fern Asplenium fontanum along a South-North transect, extending from its putative last glacial maximum (LGM) refugia in southern France towards southern Germany and eastern-central France. This study reconciles observations from distribution models and phylogeographic analyses derived from plastid and nuclear diversity. Genetic diversity distribution and niche modelling propose that genetic diversity accumulates in the LGM climate refugium in southern France with the formation of a diversity gradient reflecting a slow, post-LGM range expansion towards the current distribution range. Evidence supports the fern's preference for outcrossing, contradicting the expectation that homosporous ferns would populate new sites by single-spore colonization. Prediction of climate and distribution range change suggests that a dramatic loss of range and genetic diversity in this fern is possible. The observed migration is best described by the phalanx expansion model. The results suggest that homosporous ferns reproducing preferentially by outcrossing accumulate genetic diversity primarily in LGM climate refugia and may be threatened if these areas disappear due to global climate change.

Balancing on the Edge: An Approach to Leadership and Resiliency that Combines Rock Climbing with Four Key Touch Points

Science.gov (United States)

Winkler, Harold E.

2005-01-01

In this article, the author compares leadership and resiliency with rock climbing. It describes the author's personal experience on a rock climbing adventure with his family and how it required application of similar elements as that of leadership and resiliency. The article contains the following sections: (1) Being Resilient; (2) Points of…

New cyathealean tree ferns from the Cretaceous of South Africa: Natalipteris wildei gen. et sp. nov. and Kwazulupteris schaarschmidtii gen. et sp. nov.

Science.gov (United States)

Vera, Ezequiel Ignacio; Herbst, Rafael

2015-01-01

Two new genera and species of permineralized tree ferns, Natalipteris wildei and Kwazulupteris schaarschmidtii, are defined and described in detail. Natalipteris wildei is a solenostelic stem without well-developed sclerenchyma sheaths in their vascular strands, and has a single vascular strand in the petiole bases, which are somewhat similar to the one present in Cibotium and Nishidacaulis. On the other hand, K. schaarschmidtii is a dictyostelic fern, with petiole bases with fused adaxial arcs and a single isolated meristele in the petiolar pith. Both taxa present features that preclude their placement in the recognized families of Cyatheales, but may be referred to the "core tree ferns" clade. Fossil specimens were found in the Senckenberg Forschungsinstitut Palaeobotanical Collection and, although they lack precise stratigraphic provenance, it is suggested that they were collected from the Mzinene Formation (Albian-Turonian).

On climate adaptability of nine species of Adiantum ornamental ferns in 34 provincial capital cities,China

Directory of Open Access Journals (Sweden)

CHEN Yunhui

2015-10-01

Full Text Available Adiantum malesianum,A. myriosorum,A. capillus-junonis,A. capillus-veneris,A. caudatum,A. davadii,A. deentulum,A. edgeworthii and A. erythrochlamys are nine ornamental ferns of the family Adinataceae,with potential application prospect in the aspect of urban landscape and greening construction.To understand their climatic adaptation characteristics in 34 provincial capital cities in China,so as to provide the guidance for their cultivation.Based on 11 current biological climate data in RCP45CO2 emissions scenario,and 694 occurrence records in China,records,MaxEnt model and Arc Gis9.3 software were applied to quantitatively predict the potential distribution ranges of these nine fern species in China.The results show a quietly differences among the nine fern species in their climatic adaptation in 34 provincial capital cities.A. malesianum,A. myriosorum,A. capillus-junonis,A. capillus-veneris,A. deentulum and A. edgeworthii are more suitable grow in southwest China including Southeastern Sichuan,Chongqing,Yunnan,Guizhou,with wider potential distribution ranges;A. malesianum,A. capillus-junonis,A. capillus-veneris and A. caudatum have higher climatic adaptability in Southern China;Adiantum myriosorum,A. capillus-junonis,A. capillus-veneris,A. davadii and A. edgeworthii have higher climate adaptability in Central China;The potential distribution ranges of A. capillus-junonis and A. edgeworthii cover the north area of Beijing,Tianjin and Shijiazhuang,with their combined climate suitability index reaching as high as 0.60.

Rates of ecological divergence and body size evolution are correlated with species diversification in scaly tree ferns

Science.gov (United States)

Ramírez-Barahona, Santiago; Barrera-Redondo, Josué; Eguiarte, Luis E.

2016-01-01

Variation in species richness across regions and between different groups of organisms is a major feature of evolution. Several factors have been proposed to explain these differences, including heterogeneity in the rates of species diversification and the age of clades. It has been frequently assumed that rapid rates of diversification are coupled to high rates of ecological and morphological evolution, leading to a prediction that remains poorly explored for most species: the positive association between ecological niche divergence, morphological evolution and species diversification. We combined a time-calibrated phylogeny with distribution, ecological and body size data for scaly tree ferns (Cyatheaceae) to test whether rates of species diversification are predicted by the rates at which clades have evolved distinct ecological niches and body sizes. We found that rates of species diversification are positively correlated with rates of ecological and morphological evolution, with rapidly diversifying clades also showing rapidly evolving ecological niches and body sizes. Our results show that rapid diversification of scaly tree ferns is associated with the evolution of species with comparable morphologies that diversified into similar, yet distinct, environments. This suggests parallel evolutionary pathways opening in different tropical regions whenever ecological and geographical opportunities arise. Accordingly, rates of ecological niche and body size evolution are relevant to explain the current patterns of species richness in this ‘ancient’ fern lineage across the tropics. PMID:27412279

Rates of ecological divergence and body size evolution are correlated with species diversification in scaly tree ferns.

Science.gov (United States)

Ramírez-Barahona, Santiago; Barrera-Redondo, Josué; Eguiarte, Luis E

2016-07-13

Variation in species richness across regions and between different groups of organisms is a major feature of evolution. Several factors have been proposed to explain these differences, including heterogeneity in the rates of species diversification and the age of clades. It has been frequently assumed that rapid rates of diversification are coupled to high rates of ecological and morphological evolution, leading to a prediction that remains poorly explored for most species: the positive association between ecological niche divergence, morphological evolution and species diversification. We combined a time-calibrated phylogeny with distribution, ecological and body size data for scaly tree ferns (Cyatheaceae) to test whether rates of species diversification are predicted by the rates at which clades have evolved distinct ecological niches and body sizes. We found that rates of species diversification are positively correlated with rates of ecological and morphological evolution, with rapidly diversifying clades also showing rapidly evolving ecological niches and body sizes. Our results show that rapid diversification of scaly tree ferns is associated with the evolution of species with comparable morphologies that diversified into similar, yet distinct, environments. This suggests parallel evolutionary pathways opening in different tropical regions whenever ecological and geographical opportunities arise. Accordingly, rates of ecological niche and body size evolution are relevant to explain the current patterns of species richness in this 'ancient' fern lineage across the tropics. © 2016 The Author(s).

Isolation of polymorphic microsatellite markers and tests of cross-amplification in four widespread European calcicole ferns

NARCIS (Netherlands)

Groot, de G.A.; Korpelainen, H.; Wubs, E.R.J.; Erkens, R.H.J.

2011-01-01

Premise of the study: Studies on the biogeography and population genetics of the widespread European rock ferns Asplenium scolopendrium , A. trichomanes subsp. quadrivalens , Polystichum setiferum , and P. aculeatum would potentially yield interesting new insights into the colonization capacities of

Crowdfunding the Azolla fern genome project: a grassroots approach.

Science.gov (United States)

Li, Fay-Wei; Pryer, Kathleen M

2014-01-01

Much of science progresses within the tight boundaries of what is often seen as a "black box". Though familiar to funding agencies, researchers and the academic journals they publish in, it is an entity that outsiders rarely get to peek into. Crowdfunding is a novel means that allows the public to participate in, as well as to support and witness advancements in science. Here we describe our recent crowdfunding efforts to sequence the Azolla genome, a little fern with massive green potential. Crowdfunding is a worthy platform not only for obtaining seed money for exploratory research, but also for engaging directly with the general public as a rewarding form of outreach.

Role of route previewing strategies on climbing fluency and exploratory movements

NARCIS (Netherlands)

Seifert, Ludovic; Cordier, Romain; Orth, Dominic; Courtine, Yoan; Croft, James L.

2017-01-01

This study examined the role of route previewing strategies on climbing fluency and on exploratory movements of the limbs, in order to understand whether previewing helps people to perceive and to realize affordances. Eight inexperienced and ten experienced climbers previewed a 10 m high route of 5b

Coeval Eocene blooms of the freshwater fern Azolla in and around Arctic and Nordic seas

NARCIS (Netherlands)

Barke, J.; Burgh, A.H.P. van der; Konijnenburg-van Cittert, J.H.A. van; Collinson, M.E.; Pearce, M.A.; Bujak, J.; Heilman-Clausen, C.; Lotter, A.F.; Speelman, E.N.; Kempen, M.M.L. van; Reichart, G.-J.; Brinkhuis, H.

2012-01-01

For a short time interval (c. 1.2 Myr) during the early middle Eocene (~ 49 Myr), the central Arctic Ocean was episodically densely covered by the freshwater fern Azolla, implying sustained freshening of surface waters. Coeval Azolla fossils in neighboring Nordic seas were thought to have been

Population genetic variation in the tree fern Alsophila spinulosa (Cyatheaceae): effects of reproductive strategy.

Science.gov (United States)

Wang, Ting; Su, Yingjuan; Li, Yuan

2012-01-01

Essentially all ferns can perform both sexual and asexual reproduction. Their populations represent suitable study objects to test the population genetic effects of different reproductive systems. Using the diploid homosporous fern Alsophila spinulosa as an example species, the main purpose of this study was to assess the relative impact of sexual and asexual reproduction on the level and structure of population genetic variation. Inter-simple sequence repeats analysis was conducted on 140 individuals collected from seven populations (HSG, LCH, BPC, MPG, GX, LD, and ZHG) in China. Seventy-four polymorphic bands discriminated a total of 127 multilocus genotypes. Character compatibility analysis revealed that 50.0 to 70.0% of the genotypes had to be deleted in order to obtain a tree-like structure in the data set from populations HSG, LCH, MPG, BPC, GX, and LD; and there was a gradual decrease of conflict in the data set when genotypes with the highest incompatibility counts were successively deleted. In contrast, in population ZHG, only 33.3% of genotypes had to be removed to achieve complete compatibility in the data set, which showed a sharp decline in incompatibility upon the deletion of those genotypes. All populations examined possessed similar levels of genetic variation. Population ZHG was not found to be more differentiated than the other populations. Sexual recombination is the predominant source of genetic variation in most of the examined populations of A. spinulosa. However, somatic mutation contributes most to the genetic variation in population ZHG. This change of the primary mode of reproduction does not cause a significant difference in the population genetic composition. Character compatibility analysis represents an effective approach to separate the role of sexual and asexual components in shaping the genetic pattern of fern populations.

Marine Biodiversity in Juan Fernández and Desventuradas Islands, Chile: Global Endemism Hotspots.

Science.gov (United States)

Friedlander, Alan M; Ballesteros, Enric; Caselle, Jennifer E; Gaymer, Carlos F; Palma, Alvaro T; Petit, Ignacio; Varas, Eduardo; Muñoz Wilson, Alex; Sala, Enric

2016-01-01

The Juan Fernández and Desventuradas islands are among the few oceanic islands belonging to Chile. They possess a unique mix of tropical, subtropical, and temperate marine species, and although close to continental South America, elements of the biota have greater affinities with the central and south Pacific owing to the Humboldt Current, which creates a strong biogeographic barrier between these islands and the continent. The Juan Fernández Archipelago has ~700 people, with the major industry being the fishery for the endemic lobster, Jasus frontalis. The Desventuradas Islands are uninhabited except for a small Chilean military garrison on San Félix Island. We compared the marine biodiversity of these islands across multiple taxonomic groups. At San Ambrosio Island (SA), in Desventuradas, the laminarian kelp (Eisenia cokeri), which is limited to Desventuradas in Chile, accounted for >50% of the benthic cover at wave exposed areas, while more sheltered sites were dominated by sea urchin barrens. The benthos at Robinson Crusoe Island (RC), in the Juan Fernández Archipelago, comprised a diverse mix of macroalgae and invertebrates, a number of which are endemic to the region. The biomass of commercially targeted fishes was >2 times higher in remote sites around RC compared to sheltered locations closest to port, and overall biomass was 35% higher around SA compared to RC, likely reflecting fishing effects around RC. The number of endemic fish species was extremely high at both islands, with 87.5% of the species surveyed at RC and 72% at SA consisting of regional endemics. Remarkably, endemics accounted for 99% of the numerical abundance of fishes surveyed at RC and 96% at SA, which is the highest assemblage-level endemism known for any individual marine ecosystem on earth. Our results highlight the uniqueness and global significance of these biodiversity hotspots exposed to very different fishing pressures.

Antioxidative responses to arsenic in the arsenic-hyperaccumulator Chinese brake fern (Pteris vittata L.)

International Nuclear Information System (INIS)

Cao Xinde; Ma, Lena Q.; Tu Cong

2004-01-01

This study measured antioxidative responses of Chinese brake fern (Pteris vittata L.) upon exposure to arsenic (As) of different concentrations. Chinese brake fern was grown in an artificially-contaminated soil containing 0 to 200 mg As kg -1 (Na 2 HAsO 4 ) for 12 weeks in a greenhouse. Soil As concentrations at ≤20 mg kg -1 enhanced plant growth, with 12-71% biomass increase compared to the control. Such beneficial effects were not observed at >20 mg As kg -1 . Plant As concentrations increased with soil As concentrations, with more As being accumulated in the fronds (aboveground biomass) than in the roots and with maximum frond As concentration being 4675 mg kg -1 . Arsenic uptake by Chinese brake enhanced uptake of nutrient elements K, P, Fe, Mn, and Zn except Ca and Mg, whose concentrations mostly decreased. The contents of non-enzymatic antioxidants (glutathione, acid-soluble thiol) followed similar trends as plant As concentrations, increasing with soil As concentrations, with greater contents in the fronds than in the roots especially when exposed to high As concentrations (>50 mg kg -1 ). The activities of enzymatic antioxidants (superoxide dismutase, catalase, ascorbate peroxidase, guaiacol peroxidase) in Chinese brake followed the same trends as plant biomass, increasing with soil As up to 20 mg kg -1 and then decreased. The results indicated though both enzymatic and non-enzymatic antioxidants played significant roles in As detoxification and hyperaccumulation in Chinese brake, the former is more important at low As exposure (≤20 mg kg -1 ), whereas the latter is more critical at high As exposure (50-200 mg kg -1 ). - At low levels of arsenic exposure, enzymatic antioxidants are important for arsenic detoxification and accumulation in Chinese brake fern, while non-enzymatic antioxidants were more important at high arsenic exposure

Marine Biodiversity in Juan Fernández and Desventuradas Islands, Chile: Global Endemism Hotspots

Science.gov (United States)

Friedlander, Alan M.; Ballesteros, Enric; Caselle, Jennifer E.; Gaymer, Carlos F.; Palma, Alvaro T.; Petit, Ignacio; Varas, Eduardo; Muñoz Wilson, Alex; Sala, Enric

2016-01-01

The Juan Fernández and Desventuradas islands are among the few oceanic islands belonging to Chile. They possess a unique mix of tropical, subtropical, and temperate marine species, and although close to continental South America, elements of the biota have greater affinities with the central and south Pacific owing to the Humboldt Current, which creates a strong biogeographic barrier between these islands and the continent. The Juan Fernández Archipelago has ~700 people, with the major industry being the fishery for the endemic lobster, Jasus frontalis. The Desventuradas Islands are uninhabited except for a small Chilean military garrison on San Félix Island. We compared the marine biodiversity of these islands across multiple taxonomic groups. At San Ambrosio Island (SA), in Desventuradas, the laminarian kelp (Eisenia cokeri), which is limited to Desventuradas in Chile, accounted for >50% of the benthic cover at wave exposed areas, while more sheltered sites were dominated by sea urchin barrens. The benthos at Robinson Crusoe Island (RC), in the Juan Fernández Archipelago, comprised a diverse mix of macroalgae and invertebrates, a number of which are endemic to the region. The biomass of commercially targeted fishes was >2 times higher in remote sites around RC compared to sheltered locations closest to port, and overall biomass was 35% higher around SA compared to RC, likely reflecting fishing effects around RC. The number of endemic fish species was extremely high at both islands, with 87.5% of the species surveyed at RC and 72% at SA consisting of regional endemics. Remarkably, endemics accounted for 99% of the numerical abundance of fishes surveyed at RC and 96% at SA, which is the highest assemblage-level endemism known for any individual marine ecosystem on earth. Our results highlight the uniqueness and global significance of these biodiversity hotspots exposed to very different fishing pressures. PMID:26734732

Population genetic variation in the tree fern Alsophila spinulosa (Cyatheaceae: effects of reproductive strategy.

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Ting Wang

Full Text Available BACKGROUND: Essentially all ferns can perform both sexual and asexual reproduction. Their populations represent suitable study objects to test the population genetic effects of different reproductive systems. Using the diploid homosporous fern Alsophila spinulosa as an example species, the main purpose of this study was to assess the relative impact of sexual and asexual reproduction on the level and structure of population genetic variation. METHODOLOGY/PRINCIPAL FINDINGS: Inter-simple sequence repeats analysis was conducted on 140 individuals collected from seven populations (HSG, LCH, BPC, MPG, GX, LD, and ZHG in China. Seventy-four polymorphic bands discriminated a total of 127 multilocus genotypes. Character compatibility analysis revealed that 50.0 to 70.0% of the genotypes had to be deleted in order to obtain a tree-like structure in the data set from populations HSG, LCH, MPG, BPC, GX, and LD; and there was a gradual decrease of conflict in the data set when genotypes with the highest incompatibility counts were successively deleted. In contrast, in population ZHG, only 33.3% of genotypes had to be removed to achieve complete compatibility in the data set, which showed a sharp decline in incompatibility upon the deletion of those genotypes. All populations examined possessed similar levels of genetic variation. Population ZHG was not found to be more differentiated than the other populations. CONCLUSIONS/SIGNIFICANCE: Sexual recombination is the predominant source of genetic variation in most of the examined populations of A. spinulosa. However, somatic mutation contributes most to the genetic variation in population ZHG. This change of the primary mode of reproduction does not cause a significant difference in the population genetic composition. Character compatibility analysis represents an effective approach to separate the role of sexual and asexual components in shaping the genetic pattern of fern populations.

Modelling phytoremediation by the hyperaccumulating fern, Pteris vittata, of soils historically contaminated with arsenic

International Nuclear Information System (INIS)

Shelmerdine, Paula A.; Black, Colin R.; McGrath, Steve P.; Young, Scott D.

2009-01-01

Pteris vittata plants were grown on twenty-one UK soils contaminated with arsenic (As) from a wide range of natural and anthropogenic sources. Arsenic concentration was measured in fern fronds, soil and soil pore water collected with Rhizon samplers. Isotopically exchangeable soil arsenate was determined by equilibration with 73 As V . Removal of As from the 21 soils by three sequential crops of P. vittata ranged between 0.1 and 13% of total soil As. Ferns grown on a soil subjected to long-term sewage sludge application showed reduced uptake of As because of high available phosphate concentrations. A combined solubility-uptake model was parameterised to enable prediction of phytoremediation success from estimates of soil As, 'As-lability' and soil pH. The model was used to demonstrate the remediation potential of P. vittata under different soil conditions and with contrasting assumptions regarding re-supply of the labile As pool from unavailable forms. - This paper presents a predictive model for phytoremediation of soils, historically contaminated with arsenic, by the hyperaccumulator P. vittata.

Modelling phytoremediation by the hyperaccumulating fern, Pteris vittata, of soils historically contaminated with arsenic

Energy Technology Data Exchange (ETDEWEB)

Shelmerdine, Paula A.; Black, Colin R. [School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD (United Kingdom); McGrath, Steve P. [Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom); Young, Scott D., E-mail: scott.young@nottingham.ac.u [School of Biosciences, Biology Building, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom)

2009-05-15

Pteris vittata plants were grown on twenty-one UK soils contaminated with arsenic (As) from a wide range of natural and anthropogenic sources. Arsenic concentration was measured in fern fronds, soil and soil pore water collected with Rhizon samplers. Isotopically exchangeable soil arsenate was determined by equilibration with {sup 73}As{sup V}. Removal of As from the 21 soils by three sequential crops of P. vittata ranged between 0.1 and 13% of total soil As. Ferns grown on a soil subjected to long-term sewage sludge application showed reduced uptake of As because of high available phosphate concentrations. A combined solubility-uptake model was parameterised to enable prediction of phytoremediation success from estimates of soil As, 'As-lability' and soil pH. The model was used to demonstrate the remediation potential of P. vittata under different soil conditions and with contrasting assumptions regarding re-supply of the labile As pool from unavailable forms. - This paper presents a predictive model for phytoremediation of soils, historically contaminated with arsenic, by the hyperaccumulator P. vittata.

Bioaccumulation of selected heavy metals by the water fern, Azolla filiculoides Lam. in a wetland ecosystem affected by sewage, mine and industrial pollution

Energy Technology Data Exchange (ETDEWEB)

Wet, L.P.D. de; Schoonbee, H.J.; Pretorius, J.; Bezuidenhout, L.M. (Rand Afrikaans University, Johannesburg (South Africa). Depts. of Zoology and Botany, Research Unit for Aquatic and Terrestrial Ecosystems)

1990-10-01

The bio-accumulation of the heavy metals, Fe, Cu, Ni, Pb, Zn, Mn and Cr by the water fern, Azolla filiculoides Lam. in a wetland ecosystem polluted by effluents from sewage works, mines and industries was investigated. Results showed that the different metals can be accumulated by the water fern at concentration levels not necessarily related to their actual concentrations in the aquatic environment, as measured in this case, in the bottom sediments. 45 refs., 1 fig., 3 tabs.

Cerebellar motor learning versus cerebellar motor timing: the climbing fibre story

Science.gov (United States)

Llinás, Rodolfo R

2011-01-01

Abstract Theories concerning the role of the climbing fibre system in motor learning, as opposed to those addressing the olivocerebellar system in the organization of motor timing, are briefly contrasted. The electrophysiological basis for the motor timing hypothesis in relation to the olivocerebellar system is treated in detail. PMID:21486816

Dislocation climb models from atomistic scheme to dislocation dynamics

OpenAIRE

Niu, Xiaohua; Luo, Tao; Lu, Jianfeng; Xiang, Yang

2016-01-01

We develop a mesoscopic dislocation dynamics model for vacancy-assisted dislocation climb by upscalings from a stochastic model on the atomistic scale. Our models incorporate microscopic mechanisms of (i) bulk diffusion of vacancies, (ii) vacancy exchange dynamics between bulk and dislocation core, (iii) vacancy pipe diffusion along the dislocation core, and (iv) vacancy attachment-detachment kinetics at jogs leading to the motion of jogs. Our mesoscopic model consists of the vacancy bulk dif...

On Climbing Scalars in String Theory

CERN Document Server

Dudas, E; Sagnotti, A

2010-01-01

In string models with "brane supersymmetry breaking" exponential potentials emerge at (closed-string) tree level but are not accompanied by tachyons. Potentials of this type have long been a source of embarrassment in flat space, but can have interesting implications for Cosmology. For instance, in ten dimensions the logarithmic slope |V'/V| lies precisely at a "critical" value where the Lucchin--Matarrese attractor disappears while the scalar field is \\emph{forced} to climb up the potential when it emerges from the Big Bang. This type of behavior is in principle perturbative in the string coupling, persists after compactification, could have trapped scalar fields inside potential wells as a result of the cosmological evolution and could have also injected the inflationary phase of our Universe.

Potential of the aquatic fern Azolla filiculoides in biodegradation of an azo dye: modeling of experimental results by artificial neural networks.

Science.gov (United States)

Khataee, A R; Movafeghi, A; Vafaei, F; Lisar, S Y Salehi; Zarei, M

2013-01-01

The potential of an aquatic fern, Azolla filiculoides, in phytoremediation of a mono azo dye solution, C.I. Acid Blue 92 (AB92), was studied. The effects of operational parameters such as reaction time, initial dye concentration, fern fresh weight, pH, temperature and reusability of the fern on biodegradation efficiency were investigated. The intermediate compounds produced by biodegradation process were analyzed using GC-MS analysis. An artificial neural network (ANN) model was developed to predict the biodegradation efficiency. The findings indicated that ANN provides reasonable predictive performance (R2 = 0.961). The effects of AB92 solutions (10 and 20 mg L(-1)) on growth, chlorophylls and carotenoids content, activity of antioxidant enzymes such as superoxide dismutase, peroxidase and catalase and formation of malondialdehyde were analyzed. AB92 generally showed inhibitory effects on the growth. Moreover, photosynthetic pigments in the fronds significantly decreased in the treatments. An increase was detected for lipid peroxidation and antioxidant enzymes activity, suggesting that AB92 caused reactive oxygen species production in Azolla fronds, which were scavenged by induced activities of antioxidant enzymes.

Richness, geographic distribution and ecological aspects of the fern community within the Murici Ecological Station in the state of Alagoas, Brazil

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Anna Flora de Novaes Pereira

2013-12-01

Full Text Available We conducted a floristic survey of ferns within the Murici Ecological Station (remnant of the northeastern Atlantic Forest, located near the municipalities of Messias and Murici, in the state of Alagoas, Brazil. To increase knowledge of the ferns of Alagoas, we evaluated the species occurring in the study area in terms of richness, composition, geographic distribution, similarities with species in other Brazilian biomes, regional conservation status and ecological aspects. Data were obtained from field work conducted between March 2009 and September 2010. We identified 107 species of ferns, of which 19 represent new records for Alagoas. The richest families were Pteridaceae (29 species and Polypodiaceae (22 species. The richest genera were Adiantum (15 species and Thelypteris (9 species. Most of the species sampled are widely distributed throughout Brazil and the Americas. Within the context of the northeastern Atlantic Forest, 12 species were considered endangered. Concerning the ecological aspects, 88.8% of the species identified were herbaceous, 57.9% were terrestrial and 70.0% occurred in the forest interior.

Don Andrés Bello y don José Fernández Madrid

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Gabriel Giraldo Jaramillo

1959-05-01

Full Text Available Breve pero intensa fue la amistad de estos dos ilustres grancolombianos durante su residencia en Londres. Fernández Madrid desempeñaba el cargo de Ministro Plenipotenciario de Colombia ante el Gobierno de Su Majestad Británica y Bello estuvo por algún tiempo al frente de la secretaría de dicha misión diplomática.

A multi-component stair climbing promotional campaign targeting calorific expenditure for worksites; a quasi-experimental study testing effects on behaviour, attitude and intention

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Eves Frank F

2012-06-01

Full Text Available Abstract Background Accumulation of lifestyle physical activity is a current aim of health promotion, with increased stair climbing one public health target. While the workplace provides an opportunity for regular stair climbing, evidence for effectiveness of point-of-choice interventions is equivocal. This paper reports a new approach to worksite interventions, aimed at changing attitudes and, hence, behaviour. Methods Pre-testing of calorific expenditure messages used structured interviews with members of the public (n = 300. Effects of multi-component campaigns on stair climbing were tested with quasi-experimental, interrupted time-series designs. In one worksite, a main campaign poster outlining the amount of calorific expenditure obtainable from stair climbing and a conventional point-of-choice prompt were used (Poster alone site. In a second worksite, additional messages in the stairwell about calorific expenditure reinforced the main campaign (Poster + Stairwell messages site. The outcome variables were automated observations of stair and lift ascent (28,854 and descent (29,352 at baseline and for three weeks after the intervention was installed. Post-intervention questionnaires for employees at the worksites assessed responses to the campaign (n = 253. Analyses employed Analysis of Variance with follow-up Bonferroni t-tests (message pre-testing, logistic regression of stair ascent and descent (campaign testing, and Bonferroni t-tests and multiple regression (follow-up questionnaire. Results Pre-testing of messages based on calorific expenditure suggested they could motivate stair climbing if believed. The new campaign increased stair climbing, with greater effects at the Poster + Stairwell messages site (OR = 1.52, 95% CI = 1.40-1.66 than Posters alone (OR = 1.24, 95% CI = 1.15-1.34. Follow-up revealed higher agreement with two statements about calorific outcomes of stair climbing in the site where they

On Heels and Toes: How Ants Climb with Adhesive Pads and Tarsal Friction Hair Arrays.

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Thomas Endlein

Full Text Available Ants are able to climb effortlessly on vertical and inverted smooth surfaces. When climbing, their feet touch the substrate not only with their pretarsal adhesive pads but also with dense arrays of fine hairs on the ventral side of the 3rd and 4th tarsal segments. To understand what role these different attachment structures play during locomotion, we analysed leg kinematics and recorded single-leg ground reaction forces in Weaver ants (Oecophylla smaragdina climbing vertically on a smooth glass substrate. We found that the ants engaged different attachment structures depending on whether their feet were above or below their Centre of Mass (CoM. Legs above the CoM pulled and engaged the arolia ('toes', whereas legs below the CoM pushed with the 3rd and 4th tarsomeres ('heels' in surface contact. Legs above the CoM carried a significantly larger proportion of the body weight than legs below the CoM. Force measurements on individual ant tarsi showed that friction increased with normal load as a result of the bending and increasing side contact of the tarsal hairs. On a rough sandpaper substrate, the tarsal hairs generated higher friction forces in the pushing than in the pulling direction, whereas the reverse effect was found on the smooth substrate. When the tarsal hairs were pushed, buckling was observed for forces exceeding the shear forces found in climbing ants. Adhesion forces were small but not negligible, and higher on the smooth substrate. Our results indicate that the dense tarsal hair arrays produce friction forces when pressed against the substrate, and help the ants to push outwards during horizontal and vertical walking.

On Heels and Toes: How Ants Climb with Adhesive Pads and Tarsal Friction Hair Arrays.

Science.gov (United States)

Endlein, Thomas; Federle, Walter

2015-01-01

Ants are able to climb effortlessly on vertical and inverted smooth surfaces. When climbing, their feet touch the substrate not only with their pretarsal adhesive pads but also with dense arrays of fine hairs on the ventral side of the 3rd and 4th tarsal segments. To understand what role these different attachment structures play during locomotion, we analysed leg kinematics and recorded single-leg ground reaction forces in Weaver ants (Oecophylla smaragdina) climbing vertically on a smooth glass substrate. We found that the ants engaged different attachment structures depending on whether their feet were above or below their Centre of Mass (CoM). Legs above the CoM pulled and engaged the arolia ('toes'), whereas legs below the CoM pushed with the 3rd and 4th tarsomeres ('heels') in surface contact. Legs above the CoM carried a significantly larger proportion of the body weight than legs below the CoM. Force measurements on individual ant tarsi showed that friction increased with normal load as a result of the bending and increasing side contact of the tarsal hairs. On a rough sandpaper substrate, the tarsal hairs generated higher friction forces in the pushing than in the pulling direction, whereas the reverse effect was found on the smooth substrate. When the tarsal hairs were pushed, buckling was observed for forces exceeding the shear forces found in climbing ants. Adhesion forces were small but not negligible, and higher on the smooth substrate. Our results indicate that the dense tarsal hair arrays produce friction forces when pressed against the substrate, and help the ants to push outwards during horizontal and vertical walking.

To be active through indoor-climbing: an exploratory feasibility study in a group of children with cerebral palsy and typically developing children

DEFF Research Database (Denmark)

Christensen, Mark Schram; Jensen, Thor; Voigt, Camilla B.

2017-01-01

functional and cognitive benefits of 3 weeks of intensive climbing training in 11 children with cerebral palsy (CP) aged 11-13 years and six of their TD peers.Method: The study was designed as a feasibility and interventional study. We evaluated the amount of time spent being physically active during the 9...... in cognitive abilities or psychological well-being in any of the groups.Conclusions: These findings show that it is possible to use climbing as means to make children with CP physically active. The improved motor abilities obtained through the training is likely reflected by increased synchronization between...... be challenged functionally and cognitively, making climbing of great potential interest in (re) habilitation settings. However, until now only few research projects have investigated the feasibility of climbing as a potential activity for heightening physical activity in children with CP and the possible...

IMPLEMENTASI ALGORITMA HILL CLIMBING DAN ALGORITMA A* DALAM PENYELESAIAN PENYUSUNAN SUKU KATA DASAR DENGAN POLA PERMAINAN BINTANG KEJORA

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Nurdin Nurdin

2016-07-01

Full Text Available Permainan Bintang Kejora merupakan permainan yang sama seperti permainan pergeseran angka dalam kotak berbentuk persegi (Puzzle. Jenis permainan seperti ini cenderung mudah untuk diselesaikan. Bentuk wadah bintang menyebabkan arah pergeseran akan menjadi terbatas. Permainan bintang kejora ini cukup rumit dan sukar untuk diselesaikan secara manual. Permainan ini dapat diselesaikan dengan metode heuristik, yaitu dengan menggunakan algoritma hill climbing dan algoritma A*. Sifat algoritma hill climbing adalah mencari kemungkinan-kemungkinan dari calon solusi untuk mendapatkan yang optimal bagi penyelesaian masalah dengan mencari nilai heuristik yang terkecil. Sedangkan algoritma A* membantu menemukan solusi pencarian dalam ruang keadaan dengan mempertimbangkan nilai heuristik terbesar yang dilacak sesuai node yang akan dilewati. Pembuatan perangkat lunak ini dirancang terlebih dahulu dengan menggunakan diagram State Transition Diagram, Use Case Diagram, Activity Diagram, dan Class Diagram. Perangkat lunak ini dapat memberikan penyelesaian yang optimum atas permainan bintang kejora yang nantinya menghasilkan huruf yang sebelumnya diacak menjadi tersusun membentuk sebuah kata dasar. Hasil yang didapatkan berupa langkah-langkah ditemukan solusi serta ditampilkan waktu pencarian yang dibutuhkan dalam menemukan solusi. Pencarian A* lebih cepat menemukan solusi dibandingkan Hill Climbing, karena A* mencari nilai heuristik pada jarak yang terjauh sehingga langsung tepat menuju sasaran. Kata kunci: Hill Climbing, Algoritma A*, Bintang Kejora

Inorganic and organic nitrogen acquisition by a fern Dicranopteris dichotoma in a subtropical forest in South China.

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Xingliang Xu

Full Text Available The fern Dicranopteris dichotoma is an important pioneer species of the understory in Masson pine (Pinus massoniana forests growing on acidic soils in the subtropical and tropical China. To improve our understanding of the role of D. dichotoma in nitrogen (N uptake of these forests, a short-term (15N experiment was conducted at mountain ridge (MR, with low N level and mountain foot (MF, with high N level. We injected (15N tracers as (15NH4, (15NO3 or (15N-glycine into the soil surrounding each plant at both MR and MF sites. Three hours after tracer injection, the fern D. dichotoma took up 15NH4+ significantly faster at MF than at MR, but it showed significantly slower uptake of (15NO3- at MF than at MR. Consequently, (15NO3- made greater contribution to the total N uptake (50% to the total N uptake at MR than at MF, but (15N-glycine only contributed around 11% at both sites. Twenty-four hours after tracer injection, D. dichotoma preferred (15NH4+ (63% at MR, whereas it preferred (15NO3- (47% at MF. We concluded that the D. dichotoma responds distinctly in its uptake pattern for three available N species over temporal and spatial scales, but mainly relies on inorganic N species in the subtropical forest. This suggests that the fern employs different strategies to acquire available N which depends on N levels and time.

A Demonstration of Helping Adolescents with Mild Intellectual Disability Climb Ladders

Science.gov (United States)

Chan, Kok Hoe Anthony; Varahan, Jayashree Lakshmi; Loh, Peng Loong Daniel; Tan, Sey Ing

2011-01-01

A research team at a vocational school in Singapore, catering mainly to students between the ages of 17-21 with mild intellectual disability, studied how to best address the challenge of enabling students to learn how to climb ladders (a skill necessary at many job placements). They documented the approach used and suggested extrapolations and…

Strong congruence in tree and fern community turnover in response to soils and climate in central Panama

DEFF Research Database (Denmark)

Jones, Mirkka; Ferrier, Simon; Condit, Richard

2013-01-01

1. Plant species turnover in central Panamanian forests has been principally attributed to the effects of dispersal limitation and a strong Caribbean to Pacific gradient in rainfall seasonality. Despite marked geological heterogeneity, the role of soil variation has not been rigorously examined. 2....... We modelled the compositional turnover of trees and ferns in the Panama Canal watershed as a function of soil chemistry, climate and geographical separation, using generalized dissimilarity models (GDMs). 3. Predictability in both plant groups was strong, with 74% of turnover explained in trees...... and 49% in ferns. Major trends in the two plant groups were strikingly similar. The independent effects of soils, and of climate for trees, were sizeable, but those of geographical distance were minor. In both plant groups, distance and climatic effects on species turnover covaried strongly. 4. Including...

Relationship between the climbing up and climbing down stairs domain scores on the FES-DMD, the score on the Vignos Scale, age and timed performance of functional activities in boys with Duchenne muscular dystrophy

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Lilian A. Y. Fernandes

2014-12-01

Full Text Available BACKGROUND: Knowing the potential for and limitations of information generated using different evaluation instruments favors the development of more accurate functional diagnoses and therapeutic decision-making. OBJECTIVE: To investigate the relationship between the number of compensatory movements when climbing up and going down stairs, age, functional classification and time taken to perform a tested activity (TA of going up and down stairs in boys with Duchenne muscular dystrophy (DMD. METHOD: A bank of movies featuring 30 boys with DMD performing functional activities was evaluated. Compensatory movements were assessed using the climbing up and going down stairs domain of the Functional Evaluation Scale for Duchenne Muscular Dystrophy (FES-DMD; age in years; functional classification using the Vignos Scale (VS, and TA using a timer. Statistical analyses were performed using the Spearman correlation test. RESULTS: There is a moderate relationship between the climbing up stairs domain of the FES-DMD and age (r=0.53, p=0.004 and strong relationships with VS (r=0.72, p=0.001 and TA for this task (r=0.83, p<0.001. There were weak relationships between the going down stairs domain of the FES-DMD-going down stairs with age (r=0.40, p=0.032, VS (r=0.65, p=0.002 and TA for this task (r=0.40, p=0.034. CONCLUSION: These findings indicate that the evaluation of compensatory movements used when climbing up stairs can provide more relevant information about the evolution of the disease, although the activity of going down stairs should be investigated, with the aim of enriching guidance and strengthening accident prevention. Data from the FES-DMD, age, VS and TA can be used in a complementary way to formulate functional diagnoses. Longitudinal studies and with broader age groups may supplement this information.

Trunk and lower limb biomechanics during stair climbing in people with and without symptomatic femoroacetabular impingement.

Science.gov (United States)

Hammond, Connor A; Hatfield, Gillian L; Gilbart, Michael K; Garland, S Jayne; Hunt, Michael A

2017-02-01

Femoroacetabular impingement is a pathomechanical hip condition leading to pain and impaired physical function. It has been shown that those with femoroacetabular impingement exhibit altered gait characteristics during level walking and stair climbing, and decreased muscle force production during isometric muscle contractions. However, no studies to-date have looked at trunk kinematics or muscle activation during dynamic movements such as stair climbing in this patient population. The purpose of this study was to compare biomechanical outcomes (trunk and lower limb kinematics as well as lower limb kinetics and muscle activation) during stair climbing in those with and without symptomatic femoroacetabular impingement. Trunk, hip, knee and ankle kinematics, as well as hip, knee and ankle kinetics and muscle activity of nine lower limb muscles were collected during stair climbing for 20 people with clinical and radiographic femoroacetabular impingement and compared to 20 age- and sex-matched pain-free individuals. Those with femoroacetabular impingement ascended the stairs slower (effect size=0.82), had significantly increased peak trunk forward flexion angles (effect size=0.99) and external hip flexion moments (effect size=0.94) and had decreased peak external knee flexion moments (effect size=0.90) compared to the control group. Findings from this study indicate that while those with and without femoroacetabular impingement exhibit many biomechanical similarities when ascending stairs, differences in trunk forward flexion and joint kinetics indicate some important differences. Further longitudinal research is required to elucidate the cause of these differences as well as the clinical relevance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Hill-Climbing search and diversification within an evolutionary approach to protein structure prediction.

Science.gov (United States)

Chira, Camelia; Horvath, Dragos; Dumitrescu, D

2011-07-30

Proteins are complex structures made of amino acids having a fundamental role in the correct functioning of living cells. The structure of a protein is the result of the protein folding process. However, the general principles that govern the folding of natural proteins into a native structure are unknown. The problem of predicting a protein structure with minimum-energy starting from the unfolded amino acid sequence is a highly complex and important task in molecular and computational biology. Protein structure prediction has important applications in fields such as drug design and disease prediction. The protein structure prediction problem is NP-hard even in simplified lattice protein models. An evolutionary model based on hill-climbing genetic operators is proposed for protein structure prediction in the hydrophobic - polar (HP) model. Problem-specific search operators are implemented and applied using a steepest-ascent hill-climbing approach. Furthermore, the proposed model enforces an explicit diversification stage during the evolution in order to avoid local optimum. The main features of the resulting evolutionary algorithm - hill-climbing mechanism and diversification strategy - are evaluated in a set of numerical experiments for the protein structure prediction problem to assess their impact to the efficiency of the search process. Furthermore, the emerging consolidated model is compared to relevant algorithms from the literature for a set of difficult bidimensional instances from lattice protein models. The results obtained by the proposed algorithm are promising and competitive with those of related methods.

Hill-Climbing search and diversification within an evolutionary approach to protein structure prediction

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Chira Camelia

2011-07-01

Full Text Available Abstract Proteins are complex structures made of amino acids having a fundamental role in the correct functioning of living cells. The structure of a protein is the result of the protein folding process. However, the general principles that govern the folding of natural proteins into a native structure are unknown. The problem of predicting a protein structure with minimum-energy starting from the unfolded amino acid sequence is a highly complex and important task in molecular and computational biology. Protein structure prediction has important applications in fields such as drug design and disease prediction. The protein structure prediction problem is NP-hard even in simplified lattice protein models. An evolutionary model based on hill-climbing genetic operators is proposed for protein structure prediction in the hydrophobic - polar (HP model. Problem-specific search operators are implemented and applied using a steepest-ascent hill-climbing approach. Furthermore, the proposed model enforces an explicit diversification stage during the evolution in order to avoid local optimum. The main features of the resulting evolutionary algorithm - hill-climbing mechanism and diversification strategy - are evaluated in a set of numerical experiments for the protein structure prediction problem to assess their impact to the efficiency of the search process. Furthermore, the emerging consolidated model is compared to relevant algorithms from the literature for a set of difficult bidimensional instances from lattice protein models. The results obtained by the proposed algorithm are promising and competitive with those of related methods.

Macrobenthos of Vembanad estuary in relation to the deposition of degraded water fern Salvinia and other macrophytes

Digital Repository Service at National Institute of Oceanography (India)

Gopalan, U.K.; Meenakshikunjamma, P.P.; Vengayil, D.T.

Composition and seasonal abundance of macrobenthos in Vembanad estuary (India) seems to be influenced by the density of decaying macrophytes, especially the water fern Salvinia , deposited at the bottom of the estuary at the rate of 356.76 g/m super...

Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan vicariance and limited transoceanic dispersal.

Science.gov (United States)

Korall, Petra; Pryer, Kathleen M

2014-02-01

Scaly tree ferns, Cyatheaceae, are a well-supported group of mostly tree-forming ferns found throughout the tropics, the subtropics and the south-temperate zone. Fossil evidence shows that the lineage originated in the Late Jurassic period. We reconstructed large-scale historical biogeographical patterns of Cyatheaceae and tested the hypothesis that some of the observed distribution patterns are in fact compatible, in time and space, with a vicariance scenario related to the break-up of Gondwana. Tropics, subtropics and south-temperate areas of the world. The historical biogeography of Cyatheaceae was analysed in a maximum likelihood framework using Lagrange. The 78 ingroup taxa are representative of the geographical distribution of the entire family. The phylogenies that served as a basis for the analyses were obtained by Bayesian inference analyses of mainly previously published DNA sequence data using MrBayes. Lineage divergence dates were estimated in a Bayesian Markov chain Monte Carlo framework using beast. Cyatheaceae originated in the Late Jurassic in either South America or Australasia. Following a range expansion, the ancestral distribution of the marginate-scaled clade included both these areas, whereas Sphaeropteris is reconstructed as having its origin only in Australasia. Within the marginate-scaled clade, reconstructions of early divergences are hampered by the unresolved relationships among the Alsophila , Cyathea and Gymnosphaera lineages. Nevertheless, it is clear that the occurrence of the Cyathea and Sphaeropteris lineages in South America may be related to vicariance, whereas transoceanic dispersal needs to be inferred for the range shifts seen in Alsophila and Gymnosphaera . The evolutionary history of Cyatheaceae involves both Gondwanan vicariance scenarios as well as long-distance dispersal events. The number of transoceanic dispersals reconstructed for the family is rather few when compared with other fern lineages. We suggest that a causal

Edge effects on understory epiphytic ferns and epiphyllous bryophytes in moist afromontane forests of Ethiopia

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Hylander Kristoffer

2013-12-01

Full Text Available Most studies on edge effects in tropical forests have been conducted in landscapes with low human population density and in situations where the edges have been left unused after logging of the adjacent area. Here we studied forest margins heavily used by local farmers in a forest/agriculture mosaic landscape in Ethiopia. We compared forest structure and plant species composition across 41 forest-agriculture ecotones from 200 m out into the agricultural area to 200 m into the forest. There are strong edge effects from the edge and into the forest on canopy cover and number of stumps and apparently these forest-agricultural edges are intensively used by humans. They are penetrated by paths, beehives are found in the trees, timber of various dimensions is harvested and there is sometimes substantial cover of perennial wild (or semi-wild crops such as coffee and spices. The number of understory epiphytic fern species as well as number of epiphyllous (i.e., growing on leaves bryophyte species was lower at 20 m than at 75 m from the edge. The number of fern species was higher in newly created edges and thereafter they declined, which indicates an extinction debt. This pattern was not seen for the epiphyllous bryophytes. It is likely that different human management activities are responsible for many of the found edge effects besides wind and sun effects from the edge. Tropical forest margins provide important resources for people in many landscapes. It is important to understand how such use affects the biota of the forests. This study shows that there are substantial edge effects, but that the edge effects do not seem to become worse over time for epiphyllous bryophytes and only slightly so for ferns.

Towards a Discourse about the City in the New World: the Example of Gonzalo Fernández de Oviedo

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Álvaro Baraibar

2017-11-01

Full Text Available This paper aims to be an initial approach to the way in which Gonzalo Fernández de Oviedo puts up an specific discourse in his work at the time of describing the American city. Concretely, I have been interested in analyzing the ways the first chronicler of the American Indies adapts long-time used formulas from the old continent when he is introducing the reader to the new reality constituted by the American city. That is the case of Santo Domingo, a city to which Gonzalo Fernández de Oviedo was especially bounded. It will serve us as an example to study how the chronicler adapts the formula of the panegyric of the city to the New World.

77 FR 33777 - General Aviation Safety Forum: Climbing to the Next Level

Science.gov (United States)

2012-06-07

... NATIONAL TRANSPORTATION SAFETY BOARD General Aviation Safety Forum: Climbing to the Next Level The National Transportation Safety Board (NTSB) will convene a 2- day forum focused on safety issues related to... the Next Level,'' will be chaired by NTSB Chairman Deborah A. P. Hersman and all five Board Members...

Abrupt deceleration of molecular evolution linked to the origin of arborescence in ferns.

Science.gov (United States)

Korall, Petra; Schuettpelz, Eric; Pryer, Kathleen M

2010-09-01

Molecular rate heterogeneity, whereby rates of molecular evolution vary among groups of organisms, is a well-documented phenomenon. Nonetheless, its causes are poorly understood. For animals, generation time is frequently cited because longer-lived species tend to have slower rates of molecular evolution than their shorter-lived counterparts. Although a similar pattern has been uncovered in flowering plants, using proxies such as growth form, the underlying process has remained elusive. Here, we find a deceleration of molecular evolutionary rate to be coupled with the origin of arborescence in ferns. Phylogenetic branch lengths within the “tree fern” clade are considerably shorter than those of closely related lineages, and our analyses demonstrate that this is due to a significant difference in molecular evolutionary rate. Reconstructions reveal that an abrupt rate deceleration coincided with the evolution of the long-lived tree-like habit at the base of the tree fern clade. This suggests that a generation time effect may well be ubiquitous across the green tree of life, and that the search for a responsible mechanism must focus on characteristics shared by all vascular plants. Discriminating among the possibilities will require contributions from various biological disciplines,but will be necessary for a full appreciation of molecular evolution.

Ceratopteris richardii (C-fern: A model for investigating adaptive modification of vascular plant cell walls

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Olivier eLeroux

2013-09-01

Full Text Available Plant cell walls are essential for most aspects of plant growth, development, and survival, including cell division, expansive cell growth, cell-cell communication, biomechanical properties, and stress responses. Therefore, characterising cell wall diversity contributes to our overall understanding of plant evolution and development. Recent biochemical analyses, concomitantly with whole genome sequencing of plants located at pivotal points in plant phylogeny, have helped distinguish between homologous characters and those which might be more derived. Most plant lineages now have at least one fully sequenced representative and although genome sequences for fern species are in progress they not yet available this group. Ferns offer key advantages for the study of developmental processes leading to vascularisation and complex organs as well as the specific differences between diploid sporophyte tissues and haploid gametophyte tissues and the interplay between them. Ceratopteris richardii has been well investigated building a body of knowledge which combined with the genomic and biochemical information available for other plants will progress our understanding of wall diversity and its impact on evolution and development.

Evaluation of atpB nucleotide sequences for phylogenetic studies of ferns and other pteridophytes.

Science.gov (United States)

Wolf, P

1997-10-01

Inferring basal relationships among vascular plants poses a major challenge to plant systematists. The divergence events that describe these relationships occurred long ago and considerable homoplasy has since accrued for both molecular and morphological characters. A potential solution is to examine phylogenetic analyses from multiple data sets. Here I present a new source of phylogenetic data for ferns and other pteridophytes. I sequenced the chloroplast gene atpB from 23 pteridophyte taxa and used maximum parsimony to infer relationships. A 588-bp region of the gene appeared to contain a statistically significant amount of phylogenetic signal and the resulting trees were largely congruent with similar analyses of nucleotide sequences from rbcL. However, a combined analysis of atpB plus rbcL produced a better resolved tree than did either data set alone. In the shortest trees, leptosporangiate ferns formed a monophyletic group. Also, I detected a well-supported clade of Psilotaceae (Psilotum and Tmesipteris) plus Ophioglossaceae (Ophioglossum and Botrychium). The demonstrated utility of atpB suggests that sequences from this gene should play a role in phylogenetic analyses that incorporate data from chloroplast genes, nuclear genes, morphology, and fossil data.

Arsenic accumulation by the aquatic fern Azolla: comparison of arsenate uptake, speciation and efflux by A. caroliniana and A. filiculoides.

Science.gov (United States)

Zhang, Xin; Lin, Ai-Jun; Zhao, Fang-Jie; Xu, Guo-Zhong; Duan, Gui-Lan; Zhu, Yong-Guan

2008-12-01

This study investigates As accumulation and tolerance of the aquatic fern Azolla. Fifty strains of Azolla showed a large variation in As accumulation. The highest- and lowest-accumulating ferns among the 50 strains were chosen for further investigations. Azolla caroliniana accumulated two times more As than Azolla filiculoides owing to a higher influx velocity for arsenate. A. filiculoides was more resistant to external arsenate due to a lower uptake. Both strains showed a similar degree of tolerance to internal As. Arsenate and arsenite were the dominant As species in both Azolla strains, with methylated As species accounting for Azolla in paddy fields to reduce As transfer from soil and water to rice should be further evaluated.

Decorative values of selected cultivars of climbing roses (Rosa L. with regard to thermal conditions

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Zofia Włodarczyk

2012-12-01

Full Text Available In the years 2004-2006 in Kraków, phenological observations of climbing roses were conducted in order to determine the length and dates of their flowering period. The diameters of their flowers were also compared. Eight flowering repeating cultivars were selected for the experiment: 'Climbing Souvenir de la Malmaison', 'Dortmund', 'Golden Showers', 'Goldstern', 'New Dawn', 'Parade', 'Sympathie' and 'White New Dawn'. During the studies, the shrub roses were not artificially watered in order to create conditions similar to those prevailing in public green areas. It was observed that irrespective of the air temperature pattern in a given year, the studied cultivars did not bloom before 15 June. In 2006 high temperatures (above 20oC, which continued throughout the whole flowering period, caused its shortening, and the interval between the first and the next flowering in the season lasted longer than in the previous years. In the years 2004-2006, the cultivar 'New Dawn' bloomed the longest. In 2005 the studied cultivars produced larger flowers than the next year. The cultivars 'Dortmund' and 'White New Dawn' were characterised by the smallest diameter of flowers, whereas 'Climbing Souvenir de la Malmaison', 'Golden Showers' and 'Parade' were marked by the largest diameter.

The effect of different growth regimes on the endophytic bacterial communities of the fern, Dicksonia sellowiana hook (Dicksoniaceae

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Irene de Araújo Barros

2010-12-01

Full Text Available Endophytic bacteria associated with the fern Dicksonia sellowiana were investigated. The bacterial communities from the surface-sterilized pinnae and rachis segments of the plants from the Brazilian Atlantic Rainforest that grew in native field conditions were compared with the bacterial communities from plants grown in greenhouses and plants that were initially grown in greenhouses and then transferred to the forest. From 540 pinnae and 540 rachis segments, 163 (30.2% and 346 (64.2% were colonized by bacteria, respectively. The main bacterial genera and species that were isolated included Bacillus spp. (B. cereus, B. megaterium, B. pumilus and B. subtilis, Paenibacillus sp., Amphibacillus sp., Gracilibacillus sp., Micrococcus sp. and Stenotrophomonas spp. (S. maltophilia and S. nitroreducens. B. pumilus was the most frequently isolated bacterial species. Amphibacillus and Gracilibacillus were reported as endophytes for the first time. Other commonly found bacterial genera were not observed in D. sellowiana, which may reflect preferences of specific bacterial communities inside this fern or detection limitations due to the isolation procedures. Plants that were grown in greenhouses and plants that were reintroduced into the forest displayed more bacterial genera and species diversity than native field plants, suggesting that reintroduction shifts the bacterial diversity. Endophytic bacteria that displayed antagonistic properties against different microorganisms were detected, but no obvious correlation was found between their frequencies with plant tissues or with plants from different growth regimes. This paper reports the first isolation of endophytic bacteria from a fern.

The effect of different growth regimes on the endophytic bacterial communities of the fern, Dicksonia sellowiana hook (Dicksoniaceae).

Science.gov (United States)

de Araújo Barros, Irene; Luiz Araújo, Welington; Lúcio Azevedo, João

2010-10-01

Endophytic bacteria associated with the fern Dicksonia sellowiana were investigated. The bacterial communities from the surface-sterilized pinnae and rachis segments of the plants from the Brazilian Atlantic Rainforest that grew in native field conditions were compared with the bacterial communities from plants grown in greenhouses and plants that were initially grown in greenhouses and then transferred to the forest. From 540 pinnae and 540 rachis segments, 163 (30.2%) and 346 (64.2%) were colonized by bacteria, respectively. The main bacterial genera and species that were isolated included Bacillus spp. ( B. cereus, B. megaterium, B. pumilus and B. subtilis ) , Paenibacillus sp. , Amphibacillus sp. , Gracilibacillus sp. , Micrococcus sp. and Stenotrophomonas spp. ( S. maltophilia and S. nitroreducens ). B. pumilus was the most frequently isolated bacterial species . Amphibacillus and Gracilibacillus were reported as endophytes for the first time. Other commonly found bacterial genera were not observed in D. sellowiana , which may reflect preferences of specific bacterial communities inside this fern or detection limitations due to the isolation procedures. Plants that were grown in greenhouses and plants that were reintroduced into the forest displayed more bacterial genera and species diversity than native field plants, suggesting that reintroduction shifts the bacterial diversity. Endophytic bacteria that displayed antagonistic properties against different microorganisms were detected, but no obvious correlation was found between their frequencies with plant tissues or with plants from different growth regimes. This paper reports the first isolation of endophytic bacteria from a fern.

When Affordances Climb into Your Mind: Advantages of Motor Simulation in a Memory Task Performed by Novice and Expert Rock Climbers

Science.gov (United States)

Pezzulo, Giovanni; Barca, Laura; Bocconi, Alessandro Lamberti; Borghi, Anna M.

2010-01-01

Does the sight of multiple climbing holds laid along a path activate a motor simulation of climbing that path? One way of testing whether multiple affordances and their displacement influence the formation of a motor simulation is to study acquired motor skills. We used a behavioral task in which expert and novice rock climbers were shown three…

Conservation of a medieval climbing stem by freeze-drying and resin impregnation

International Nuclear Information System (INIS)

Schaudy, R.; Slais, E.; Eibner, C.

1985-12-01

The conservation of a climbing stem originating from a medieval mining adit is described. The fragile wet object was preserved by a combined process consisting of freeze-drying after a polyethylene glycol bath and consecutive resin impregnation with curing by gamma irradiation. The whole conservation process took 1 year. The result is discussed. (Author)

Engineers find climbing techniques work well for dam inspections

Energy Technology Data Exchange (ETDEWEB)

O`Shea, M.; Graves, A. [Bureau of Reclamation, Denver, CO (United States)

1996-10-01

Climbing techniques adopted by the Bureau of Reclamation to inspect previously inaccessible or difficult to reach features at dams are described. Following the failure of the steel radial-arm gate at Folsom Dam, engineers mounted an effort to reach and inspect the dam`s seven other spillway gates. This close-up examination was performed to: (1) determine the condition of these gates; and (2) gather clues about the failure of the one gate. The access techniques described involved mountaineering techniques, as opposed to high scaling techniques, performed with dynamic and static nylon kermantle ropes.

Multi-Objective Climb Path Optimization for Aircraft/Engine Integration Using Particle Swarm Optimization

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Aristeidis Antonakis

2017-04-01

Full Text Available In this article, a new multi-objective approach to the aircraft climb path optimization problem, based on the Particle Swarm Optimization algorithm, is introduced to be used for aircraft–engine integration studies. This considers a combination of a simulation with a traditional Energy approach, which incorporates, among others, the use of a proposed path-tracking scheme for guidance in the Altitude–Mach plane. The adoption of population-based solver serves to simplify case setup, allowing for direct interfaces between the optimizer and aircraft/engine performance codes. A two-level optimization scheme is employed and is shown to improve search performance compared to the basic PSO algorithm. The effectiveness of the proposed methodology is demonstrated in a hypothetic engine upgrade scenario for the F-4 aircraft considering the replacement of the aircraft’s J79 engine with the EJ200; a clear advantage of the EJ200-equipped configuration is unveiled, resulting, on average, in 15% faster climbs with 20% less fuel.

Flexible Structural Design for Side-Sliding Force Reduction for a Caterpillar Climbing Robot

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Weina Cui

2012-11-01

Full Text Available Due to sliding force arising from the closed chain mechanism among the adhering points of a climbing caterpillar robot (CCR, a sliding phenomenon will happen at the adhering points, e.g., the vacuum pads or claws holding the surface. This sliding force makes the attachment of the climbing robot unsteady and reducesthe motion efficiency. According to the new bionic research on the soft-body structure of caterpillars, some flexible structures made of natural rubber bars are applied in CCRs correspondingly as an improvement to the old rigid mechanical design of the robotic structure. This paper firstly establishes the static model of the sliding forces, the distortion of flexible bars and the driving torques of joints. Then, a method to reduce the sliding force by exerting a compensating angle to an active joint of the CCR is presented. The analyses and experimental results indicate that the flexible structure and the compensating angle method can reduce the sliding forces remarkably.

The Effect of Climbing as a Recreational Event on Adoles ent ’ s Locus of Control

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Güçlü ÖZEN

2014-07-01

Full Text Available The aim of this study was to determine the effect of experience of the secondary education ( class 10th and 11th students‟ participation on artificial wall climbing refe r r ed to experiential learning education and defined as high activity on th eir locus of control . Artifical wall climbing is a learning point beyond the sport act ivity that give an opportunity to participants recognize their own limits and others and do they active not passive . This study was done as pretest - posttest control group with quasi - experimental model and the data were collected using „ Nowicki - Strickland Locus of Control Scale‟ adapted to Turkish by Yeşilyaprak (1988 . In this research, 90 students (40 female, 50 male aged 17 ,75 ±1.06 participated voluntery and divided in two groups as a trail and control group randomly. Trial group participated artifcial wall climbing twice a week, totel six weeks. During this time period the control group not join any activity has continued to normal life. As a result of the statistical analysis, no significant difference s were found between control and trial groups pre - test scores (p>0.05. No significant difference s were found between pre and post - test scores of control group (p>0.05, significant differences were found between pre and post - test scores of trial group (p0.05 and no significant differences between the difference of the differences (p>0.05. C onsequently, it could be said that the articifal wall climbing activities has a positive efect on the particip ants‟ locus of control, it caused a movement from out side to inside. And it has a significant effect on gender differences, that women have more gain than men.

Innovative gait robot for the repetitive practice of floor walking and stair climbing up and down in stroke patients

OpenAIRE

Hesse, Stefan; Waldner, Andreas; Tomelleri, Christopher

2010-01-01

Abstract Background Stair climbing up and down is an essential part of everyday's mobility. To enable wheelchair-dependent patients the repetitive practice of this task, a novel gait robot, G-EO-Systems (EO, Lat: I walk), based on the end-effector principle, has been designed. The trajectories of the foot plates are freely programmable enabling not only the practice of simulated floor walking but also stair climbing up and down. The article intended to compare lower limb muscle activation pat...

Effects of stair-climbing on balance, gait, strength, resting heart rate, and submaximal endurance in healthy seniors.

Science.gov (United States)

Donath, L; Faude, O; Roth, R; Zahner, L

2014-04-01

Stair-climbing serves as a feasible opportunity to remain physically active within everyday-life. Data on neuromuscular and cardiorespiratory performance after regular stair-climbing in seniors are scarce. Forty-eight seniors were stratified to a one- (taking every step, INT1) or two-step strategy (every second step, INT2) or a control group (CON). Thirty-nine seniors [females: n = 22, males: n = 17; age: 70.5 (SD 5.1) years; BMI: 25.8 (3.1) kg/m(2)] completed the 8-week intervention (three weekly sessions). Before and after the intervention, balance, gait, strength, and submaximal endurance (at different intensities) were assessed. Maximal strength and explosive power did not improve significantly (0.10 walking significantly decreased (-11/min; P beam balancing (4.5 cm width) increased in INT2 (P = 0.007) compared with CON. With more pronounced effects in INT2, stair-climbing significantly improved resting and exercise heart rates, perceived exertion, and dynamic balance performance in healthy seniors and may contribute to better overall fitness, reduced fall risk, and less perceived strain during daily life activities. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Thermally switchable adhesions of polystyrene-block-poly(n-isopropylacrylamide) copolymer pillar array mimicking climb attitude of geckos

Science.gov (United States)

Chen, Jem-Kun; Wang, Jing-Hong; Chang, Jia-Yaw; Fan, Shih-Kang

2012-09-01

Inspired by the gecko foot pad, we fabricated polystyrene-block-poly(N-isopropylacrylamide) (PS-b-PNIPAAm) copolymer pillar array to mimic climbing attitude of a gecko, alternately attach to and detach from a surface. The pillar array structure of the PS segment significantly enhances both of the hydrophilic and hydrophobic property of PNIPAAm segment tips at 25 and 50 °C, respectively, which could generate alternating adhesive forces of approximately 120 and 11 nN. The dramatic change in adhesive and friction force difference at 25 and 50 °C may guide the design of bio-inspired artificial analogues, which could approach gecko's climbing behavior.

Physiological responses to simulated stair climbing in professional firefighters wearing rubber and leather boots.

Science.gov (United States)

Huang, Chun-Jung; Garten, Ryan S; Wade, Chip; Webb, Heather E; Acevedo, Edmund O

2009-09-01

No studies have considered whether a firefighter's boots are a factor influencing physiological responses. The purpose of this study was to examine physiological responses to a fire simulation activity (stair climb) in professional firefighters wearing rubber boots (RB) and leather boots (LB). Twelve professional firefighters participated in two counterbalanced simulated firefighter stair climb (SFSC) sessions, one wearing RB and the other wearing LB. Heart rate, oxygen uptake (VO(2)), expiratory ventilation (V(E)), blood lactate (BLa), salivary cortisol (SCORT), and leg strength were assessed prior to and following a SFSC. LB elicited significantly greater SCORT values and knee flexion time to peak torque. Furthermore, RB revealed significantly greater ankle dorsiflexion peak torque after SFSC. BLa was positively related to knee flexion peak torque after SFSC in the RB. Firefighters when wearing the RB may be more effective at resisting fatigue and increase more force production.

Arbuscular mycorrhizal colonization in field-collected terrestrial cordate gametophytes of pre-polypod leptosporangiate ferns (Osmundaceae, Gleicheniaceae, Plagiogyriaceae, Cyatheaceae).

Science.gov (United States)

Ogura-Tsujita, Yuki; Hirayama, Yumiko; Sakoda, Aki; Suzuki, Ayako; Ebihara, Atsushi; Morita, Nana; Imaichi, Ryoko

2016-02-01

To determine the mycorrhizal status of pteridophyte gametophytes in diverse taxa, the mycorrhizal colonization of wild gametophytes was investigated in terrestrial cordate gametophytes of pre-polypod leptosporangiate ferns, i.e., one species of Osmundaceae (Osmunda banksiifolia), two species of Gleicheniaceae (Diplopterygium glaucum, Dicranopteris linearis), and four species of Cyatheales including tree ferns (Plagiogyriaceae: Plagiogyria japonica, Plagiogyria euphlebia; Cyatheaceae: Cyathea podophylla, Cyathea lepifera). Microscopic observations revealed that 58 to 97% of gametophytes in all species were colonized with arbuscular mycorrhizal (AM) fungi. Fungal colonization was limited to the multilayered midrib (cushion) tissue in all gametophytes examined. Molecular identification using fungal SSU rDNA sequences indicated that the AM fungi in gametophytes primarily belonged to the Glomeraceae, but also included the Claroideoglomeraceae, Gigasporaceae, Acaulosporaceae, and Archaeosporales. This study provides the first evidence for AM fungal colonization of wild gametophytes in the Plagiogyriaceae and Cyatheaceae. Taxonomically divergent photosynthetic gametophytes are similarly colonized by AM fungi, suggesting that mycorrhizal associations with AM fungi could widely occur in terrestrial pteridophyte gametophytes.

Hamilton-Jacobi-Bellman approach for the climbing problem for heavy launchers

OpenAIRE

Bokanowski , Olivier; Cristiani , Emiliano; Laurent-Varin , Julien; Zidani , Hasnaa

2012-01-01

International audience; In this paper we investigate the Hamilton-Jacobi-Bellman (HJB) approach for solving a complex real-world optimal control problem in high dimension. We consider the climbing problem for the European launcher Ariane V: The launcher has to reach the Geostationary Transfer Orbit with minimal propellant consumption under state/control constraints. In order to circumvent the well-known curse of dimensionality, we reduce the number of variables in the model exploiting the spe...

A survey of safety issues in tree-climbing applications for forestry management

Directory of Open Access Journals (Sweden)

D. Longo

2013-09-01

Full Text Available Topping, trimming, consolidation, securing and felling are very common operations in arboriculture, in city park as well as in forests. In case of very large trees, these operations are often not possible from ground level using ladders or Mobile Elevating Work Platforms (MEWPs because of excessive height or uneven/inaccessible terrain. In past years, different people start applying techniques, materials and procedures normally used in mountaineering and caving, to climb trees and these techniques start to be applied to forestry management operations; these techniques are now worldwide used. Work activities at height, as tree-climbing for forestry management purpose, are regulated in Italy by Legislative Decree 81/08 about safety in the workplace, as this activity expose operators to fall from height and many other risks. Moreover, as this activity involves the use of specific tools, operators must be trained (with periodic refreshment and tools must been periodically checked by authorised operators. The objective of this work is to present and synthesise regulations and some technical aspects in order to allow operators to better understand different issues and general principles related to this activity.

The freshwater fern Azolla (Azollaceae) from Eocene Arctic and Nordic Sea sediments: New species and their stratigraphic distribution

NARCIS (Netherlands)

van der Burgh, J.; Collinson, M.E.; van Konijnenburg-van Cittert, J.H.A.; Barke, J.; Brinkhuis, H.

2013-01-01

Three new species of the freshwater fern Azolla are described from Eocene marine deposits of the Arctic and Nordic seas, bringing the total number of species now documented from these areas to five. Azolla arctica Collinson et al., Azolla jutlandica Collinson et al., Azolla nova sp. nov. and Azolla

New additions to the introduced flora of the Juan Fernández Islands: origin, distribution, life history traits, and potential of invasion Nuevas adiciones a la flora introducida de las Islas Juan Fernández: origen, distribución, rasgos de historia de vida y potencial de invasión

Directory of Open Access Journals (Sweden)

JAIME G. CUEVAS

2004-09-01

Full Text Available Oceanic islands, such as Juan Fernández in Chile, are the home for particular biotas that have evolved in isolation over a long period. The anthropogenic introduction of allochtonous plants is one of many problems for the conservation of endemic elements. In this paper, we present the new additions to the introduced flora of the Juan Fernández Islands, adding some comments about their life form, origin, morphological characteristics, ecology, distribution, abundance, and their potential of invasion. We cited 27 new species, 12 new genera, and three new families for the Juan Fernández flora (Amaryllidaceae, Commelinaceae and Violaceae. Most genera belonged to Asteraceae (seven species. Fifty-nine percent of taxa were perennial herbs, followed by annual or biennial herbs. Wind was the main vector of propagule dispersal (42 %, followed by vegetative dispersal (23 %. Fifty-two percent of the species were weeds and 44 % were plants with dual behaviour: garden-weed plant. Eurasia was the most frequent area of plant origin (70 %. Ninety-four percent of the taxa with known geographic range are in the V Region of mainland Chile, which is the main region of export of plants and materials to the archipelago, suggesting that this may have been the immediate origin of these introductions. Sixty-three percent of the species were only found in the San Juan Bautista urban area, while the remaining taxa were also (22 % or exclusively (15 % found in other places of the main island (Robinson Crusoe. Sixteen species (59 % are considered as noxious weeds in Juan Fernández or elsewhere, and they should be a focus of attention and, eventually, control. Summing our findings to previous lists of introduced taxa, we obtained 260 non-native taxa in Juan Fernández. This number is greater than the native taxa (211, which demonstrate how the human intentional and non-intentional action can dramatically change the floristic composition of an oceanic archipelago. We

Imaging of metal bioaccumulation in Hay-scented fern (Dennstaedtia punctilobula) rhizomes growing on contaminated soils by laser ablation ICP-MS

International Nuclear Information System (INIS)

Koelmel, Jeremy; Amarasiriwardena, Dulasiri

2012-01-01

Understanding Pb removal from the translocation stream is vital to engineering Pb hyperaccumulation in above ground organs, which would enhance the economic feasibility of Pb phytoextraction technologies. We investigated Cu, Pb, Sb and Zn distributions in Hay-scented fern (Dennstaedtia punctilobula) rhizomes on shooting range soils by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), analyzing digested rhizomes, stems, and fronds using ICP-MS. Nutrients Cu and Zn concentrated in fronds while toxic elements Pb and Sb did not, showing potential Pb and Sb sequestration in the rhizome. Frond and rhizome concentration of Pb was 0.17 ± 0.10% and 0.32 ± 0.21% of dry biomass, respectively. The 208 Pb/ 13 C and 121 Sb/ 13 C determined by LA-ICP-MS increased from inner sclerotic cortex to the epidermis, while Pb concentrated in the starchy cortex only in contaminated sites. These results suggest that concentration dependent bioaccumulation in the rhizome outer cortex removes Pb from the vascular transport stream. - Highlights: ► Bioimaged Cu, Pb, Sb, Zn across fern rhizomes from shooting ranges using LA-ICP-MS. ► Pb levels were highest in the outer starchy cortex. ► Pb seemed to displace nutrients Cu and Zn in contaminated site rhizomes. ► [Pb] and [Sb] were correlated across organs suggesting similar transport factors. - Using LA-ICP-MS we determined elemental distributions in Hay-scented fern rhizomes including concentration dependent Pb sequestration patterns in the outer cortex.

A study on a wheel-based stair-climbing robot with a hopping mechanism

Science.gov (United States)

Kikuchi, Koki; Sakaguchi, Keisuke; Sudo, Takayuki; Bushida, Naoki; Chiba, Yasuhiro; Asai, Yuji

2008-08-01

In this study, we propose a simple hopping mechanism using the vibration of a two-degree-of-freedom system for a wheel-based stair-climbing robot. The robot, consisting of two bodies connected by springs and a wire, hops by releasing energy stored in the springs and quickly travels using wheels mounted in its lower body. The trajectories of the bodies during hopping change in accordance with the design parameters, such as the reduced mass of the two bodies, the mass ratio between the upper and lower bodies, the spring constant, the control parameters such as the initial contraction of the spring and the wire tension. This property allows the robot to quickly and economically climb up and down stairs, leap over obstacles, and landing softly without complex control. In this paper, the characteristics of hopping motion for the design and control parameters are clarified by both numerical simulations and experiments. Furthermore, using the robot design based on the results the abilities to hop up and down a step, leap over a cable, and land softly are demonstrated.

Understanding mechanisms of rarity in pteridophytes: competition and climate change threaten the rare fern Asplenium scolopendrium var. americanum (Aspleniaceae).

Science.gov (United States)

Testo, Weston L; Watkins, James E

2013-11-01

Understanding the ecology of rare species can inform aspects of conservation strategies; however, the mechanisms of rarity remain elusive for most pteridophytes, which possess independent and ecologically distinct gametophyte and sporophyte generations. To elucidate factors contributing to recent declines of the rare fern Asplenium scolopendrium var. americanum, we studied the ecology and ecophysiology of its gametophyte generation, focusing on responses to competition, temperature, and water stress. Gametophytes of A. scolopendrium var. americanum, its widespread European relative A. scolopendrium var. scolopendrium, and five co-occurring fern species were grown from spores. Gametophytes were grown at 20°C and 25°C, and germination rates, intra- and interspecific competition, desiccation tolerance, and sporophyte production were determined for all species. Gametophytes of A. scolopendrium var. americanum had the lowest rates of germination and sporophyte production among all species studied and exhibited the greatest sensitivity to interspecific competition, temperature increases, and desiccation. Mature gametophytes of A. scolopendrium var. americanum grown at 25°C were 84.6% smaller than those grown at 20°C, and only 1.5% produced sporophytes after 200 d in culture. Similar responses were not observed in other species studied. The recent declines and current status of populations of A. scolopendrium var. americanum are linked to its gametophyte's limited capacity to tolerate competition and physiological stress linked to climate change. This is the first study to develop a mechanistic understanding of rarity and decline in a fern and demonstrates the importance of considering the ecology of the gametophyte in plants with independent sporophyte and gametophyte generations.

Mesobathic chondrichthyes of the Juan Fernández seamounts: are they different from those of the central Chilean continental slope?

Directory of Open Access Journals (Sweden)

Isabel Andrade

2008-03-01

Full Text Available We compared the geographic distribution of groups of chondrychthid fishes of two physically proximal, although geographically different, regions that include the Juan Fernández seamounts and the central Chilean continental slope, both sampled at mesopelagic and mesobenthonic depths. The ridge is in the Nazca Plate, while the slope region in on the South American Plate, and is closer to the South American continent. We found six species of Chondrichthyes for the seamounts (four orders, four families. The slope sampling produced ten species of Chondrichthyes, of which Torpedo tremens De Buen 1959, was the only species in common with the Juan Fernández area. There are clear differences between the Chondrichthyes of the two regions. These fisheries require adequate administrative modes. Rev. Biol. Trop. 56 (1: 181-190. Epub 2008 March 31.

Raíces medievales del nacional catolicismo: el Poema de Fernán González

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Moreno Hernández, Carlos

2000-06-01

Full Text Available The Poema de Fernán González, a clerical poem written in the second half of the XIIIth century, includes already the national catholic ideology governing Spain up to the present, a religious fundamentalism that christians in the castilian kingdom did oppose to the one by their muslim enemies, always permeating the stories about this half legendary nobleman and exemplifying the blurring borders between history and literature before the XlXth century.[fr] Le Poema de Fernán González, poème de clérecie redige pendant la seconde moitié du XIIème siècle, resume déjà l'idéologie du national catolicisme qui va s'imposer en Espagne jusqu'à nos jours. Il s'agit d'un fondamentalisme religieux que les chrétiens du royaume castillan finirent par opposser à celui de ses énemis musulmans et qu'on peut trouver aussi dans tous les récits ultérieurs sur le comte, exemples des frontières peu claires entre les domaines historique et littéraire jusqu'au XIXème siècle.

Dylan Thomas’s “Fern Hill”: The Poets’s Passion for Auden’s Greatness

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S. Bharadwaj

2017-09-01

Full Text Available The poem “Fern Hill” is interpreted as autobiographical and reminiscent of Dylan Thomas’s boyhood holidays. A reading of the figurative language of the poem, the process of playing with its tropes can be the basis of right interpretation independent of the poet’s life or an historical context. As the poem seeks to be persuasive and objective, it relies more on rhetorics suggesting the sufferings of the fallen poets of the thirties and the war poet of the forties owing to their wild love of the transcendental art of W.H.Auden’s Poems (1930 considered as touchstone of great poetry and a hope for self-advancement in life. However, it is the paradoxical poems of Thomas and his vicarious poetical character that have rehabilitated and revamped the depressed poets. “Fern Hill” reaffirms and reassures the continuation of the same sceptic poetic tradition and culture which Thomas has cherished in all the preceeding and the succeeding poems. What this paper, keeping the contemporary poets’s passion for Auden’s greatness and glory, their dreams and destinations as focal point, strives to convey is the liberating power of Thomas’s moral disinterestedness, his vicarious comic vision and his poetic process of life-in-death contrasted with  the amoral aesthetic disinterestedness of Auden, his historic tradition and his poetic process of death-in-life.

Comparisons of micrometeorology, growth of leather-fern [Rumohra adiantiformis, pteridophyta] and comfortable working environment between PO-film-covered and net-covered greenhouses in summer

International Nuclear Information System (INIS)

Yokoyama, H.; Harazono, Y.

2004-01-01

Protected cultivation of leather-fern in Hachijo-Island has been urged to prevent the Mottled Yellowing Syndrome (MYS) damage and to reduce the production costs. The purpose of the study was to reveal greenhouse environments that would provide good plant growth, a comfortable working environment and low-cost management, by comparing the micrometeorology and leatherfern productivity between Poly-Olefin (PO) film-covered greenhouses and the conventional netcovered greenhouses. Both greenhouses were fully covered by the same net. Field studies of leather-fern cultivation in Hachijo-Island showed that better productivity and quality of leather-fern have been provided by farmer's net-covered greenhouses than by farmer's PO-covered greenhouses. The light transmittance in the net-covered greenhouse was higher and the air temperature was lower than those in the PO-covered greenhouse. The comparative experiments using PO-covered greenhouses (PO), and net-covered greenhouses (NET), were conducted at the Hachijojima Horticultural Research Center. Air temperature and its vertical gradient in NET were lower than those in PO. Irrigation in PO was 225 mm during August and September in 1999, but 507 mm of precipitation in addition to the irrigation was supplied in NET. Air temperature and its vertical gradient in PO increased with solar radiation increase. Heat disorder in working environments for farmers did not occur in the NET, but several warning hours of heat disorder occurred in the PO as a dangerous working environment. The NET was thought to be a better system of leather-fern cultivation bringing about low costs and comfortable working environments. However, further application of fully rolled-up PO-film greenhouse system was recommended to control the soil water condition

THE IMPACT OF SPORT CLIMBING ON SOME MORPHOLOGICAL CHARACTERISTICS AND MOTOR ABILITIES IN CLIMBERS OF 14 YEARS OF AGE

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Blaž Jereb

2009-11-01

Full Text Available The objective of our research was to identify the impact of sport climbing on some morphologic characteristics and motor abilities in climbers. The sample group consisted of 19 climbers, who trained climbing for one year beside their regular physical education after the initially survey was made, and 72 nonclimbers, who’s only sport activity was their regular physical education. At the time of the test, climbers as well as nonclimbers were 14 years of age. The measurement included all the variables from the Physical education chart. Data were processed with statistical programme package SPSS for Windows. The result of analysis of covariance show that after a year long period of sport climbing statistically significant differences were shown in the results of t he test Polygon backwards in favour of the experimental group. It is also possible to observe a trend towards better results of the experimental group in the tests Skin fold thickness of the upper arm and Bend and touch on bench. The nonclimbers achieved larger differences than climbers in torso lifting and 600 m run.

Local adaptation despite high gene flow in the waterfall-climbing Hawaiian goby, Sicyopterus stimpsoni.

Science.gov (United States)

Moody, K N; Hunter, S N; Childress, M J; Blob, R W; Schoenfuss, H L; Blum, M J; Ptacek, M B

2015-02-01

Environmental heterogeneity can promote the emergence of locally adapted phenotypes among subpopulations of a species, whereas gene flow can result in phenotypic and genotypic homogenization. For organisms like amphidromous fishes that change habitats during their life history, the balance between selection and migration can shift through ontogeny, making the likelihood of local adaptation difficult to predict. In Hawaiian waterfall-climbing gobies, it has been hypothesized that larval mixing during oceanic dispersal counters local adaptation to contrasting topographic features of streams, like slope gradient, that can select for predator avoidance or climbing ability in juvenile recruits. To test this hypothesis, we used morphological traits and neutral genetic markers to compare phenotypic and genotypic distributions in recruiting juveniles and adult subpopulations of the waterfall-climbing amphidromous goby, Sicyopterus stimpsoni, from the islands of Hawai'i and Kaua'i. We found that body shape is significantly different between adult subpopulations from streams with contrasting slopes and that trait divergence in recruiting juveniles tracked stream topography more so than morphological measures of adult subpopulation differentiation. Although no evidence of population genetic differentiation was observed among adult subpopulations, we observed low but significant levels of spatially and temporally variable genetic differentiation among juvenile cohorts, which correlated with morphological divergence. Such a pattern of genetic differentiation is consistent with chaotic genetic patchiness arising from variable sources of recruits to different streams. Thus, at least in S. stimpsoni, the combination of variation in settlement cohorts in space and time coupled with strong postsettlement selection on juveniles as they migrate upstream to adult habitats provides the opportunity for morphological adaptation to local stream environments despite high gene flow. © 2014

Phytoextraction and accumulation of mercury in three plant species: Indian mustard (Brassica juncea), beard grass (Polypogon monospeliensis), and Chinese brake fern (Pteris vittata).

Science.gov (United States)

Su, Yi; Han, Fengxiang X; Chen, Jian; Sridhar, B B Maruthi; Monts, David L

2008-01-01

The objective of this research was to screen and search for suitable plant species to phytoextract mercury-contaminated soil. Our effort focused on using some of the known metal-accumulating wild-type plants since no natural plant species with mercury-hyperaccumulat ing properties has yet been identified. Three plant species were evaluated for their uptake efficiency for mercury: Indian mustard (Brassica juncea), beard grass (Polypogon monospeliensis), and Chinese brake fern (Pteris vittata). Four sets of experiments were conducted to evaluate the phytoremediation potential of these three plant species: a pot study with potting mix where mercury was provided daily as HgCl2 solution; experiments with freshly mercury-spiked soil; and a study with aged soils contaminated with different mercury sources (HgCl2, Hg(NO3)2, and HgS). Homemade sunlit chambers were also used to study foliar uptake of Hg from ambient air. Among the three plant species, Chinese brake fern showed the least stress symptoms resulting from mercury exposure and had the highest mercury accumulation. Our results indicate that Chinese brake fern may be a potential candidate for mercury phytoextraction. We found that mercury contamination is biologically available for plant uptake and accumulation, even if the original and predominating mercury form is HgS, and also after multiple phytoremediation cycles.

Micromycetes on climbing roses leaves (Rosa L. in the Botanic Garden of the Jagiellonian University in Cracow

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Maria Kowalik

2015-08-01

Full Text Available Micromycetes inhabiting the leaves of 20 cultivars of climbing roses (Rosa L., grown in Botanic Garden of the Jagiellonian University in Cracow was investigated in the three successive years of research. Sixty-five taxa of of micromycetes was recorded with a few species dominating: Alternaria alternata, Epicoccum nigrum, Pestalotia rosae, Penicillium brevicompactum and Sordaria fimicola, accompanied by various other microfungi. A high abundance of rose black spot caused by Diplocarpon rosae was also observed. The affected leaves revealed advancing necrosis, substantially enhancing at the end of the growing season. Defoliation took place from June to October. Micromycetes inhabiting the leaves of climbing roses in Botanic Garden of the Jagiellonian University in Cracow considerably deteriorated the decorative aspect of the plants.

La poética de la Nocilla: Transmedia Poetics in Agustín Fernández Mallo’s Complete Works.

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Alex Saum-Pascual

2014-06-01

Full Text Available Moving beyond current applications of transmedia storytelling, this essay looks at the work of Spanish author Agustín Fernández Mallo to explore how his engagement with the media landscape is both a revolution and a contribution to fundamental concepts in contemporary literature such as authorship and narrative structure. On the one hand, transmedia storytelling provides a structure to frame Fernández Mallo’s versatile and multimedia production, exploring both the productive semiotic intermedial breakages within works, as well as analyzing his complete production as a whole: one single poetic “work” encapsulated into a transmedia universe composed of multiple autonomous narratives. On the other, the fictionalization of his Author function as a parodied metafictional object within this transmedia universe can shed some light on the role of the writer within a larger network of media convergence and neoliberal enterprises.

Dislocation Climb Sources Activated by 1 MeV Electron Irradiation of Copper-Nickel Alloys

DEFF Research Database (Denmark)

Barlow, P.; Leffers, Torben

1977-01-01

Climb sources emitting dislocation loops are observed in Cu-Ni alloys during irradiation with 1 MeV electrons in a high voltage electron microscope. High source densities are found in alloys containing 5, 10 and 20% Ni, but sources are also observed in alloys containing 1 and 2% Ni. The range of ...

Revision of the Pennsylvanian fern .i.Boweria./i. Kidston and the establishment of the new genus .i.Kidstoniopteris./i.

Czech Academy of Sciences Publication Activity Database

Frojdová, Jana; Pšenička, J.; Bek, Jiří; Cleal, Ch. J.

2017-01-01

Roč. 236, January (2017), s. 33-58 ISSN 0034-6667 R&D Projects: GA ČR(CZ) GAP210/12/2053 Institutional support: RVO:67985831 Keywords : Boweria * Kidstoniopteris * fern * Pennsylvanian * in situ spores * taxonomy * cuticles Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.817, year: 2016

Impact of Carbohydrate-Electrolyte Beverage Ingestion on Heart Rate Response While Climbing Mountain Fuji at ~3000 m

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Masahiro Horiuchi

2017-01-01

Full Text Available We sought to investigate whether carbohydrate-electrolyte beverage ingestion reduced heart rate (HR in twenty-three healthy young adults while climbing Mount Fuji at a given exercise intensity. Twenty-three healthy adults were randomly divided into two groups: the tap water (11 males [M] and 1 female [F] and the carbohydrate-electrolyte group (10 M and 1 F. HR and activity energy expenditure (AEE were recorded every min. The HRs for the first 30 minutes of climbing were not significantly different between the groups [121 ± 2 beats per min (bpm in the tap water and 116 ± 3 bpm in the carbohydrate-electrolyte]; however, HR significantly increased with climbing in the tap water group (129 ± 2 bpm but showed no significant increase in the carbohydrate-electrolyte group (121 ± 3 bpm. In addition, body weight changes throughout two days ascending and descending on Mount Fuji were inversely related to changes in resting HR. Further, individual variation of body weight changes was suppressed by carbohydrate-electrolyte drink. Collectively, carbohydrate-electrolyte beverage intake may attenuate an increase in HR at a given AEE while mountaineering at ~3000 m compared with tap water intake.

CLASSICAL AND ROMANTIC FEATURES IN BEETHOVEN’S SONG CYCLE AN DIE FERNE GELIEBTE

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TUREA ELENA

2016-12-01

Full Text Available This article examines the cycle of songs An die ferne Geliebte written by Beethoven in 1816 as the fi rst example of a vocal cycle in the history of music. It is investigated in terms of correlation between the classical and romantic features pursued both in the content and structural aspect. It features the presentiment of the romantic lied in the musical language and development principles of the thematic material, in morphogenesis. Th e semantic correlations between the cycle numbers and the melodicrhythmic ties are highlighted, special emphasis is laid on the piano part in the dramaturgy of the whole.

On factoring RSA modulus using random-restart hill-climbing algorithm and Pollard’s rho algorithm

Science.gov (United States)

Budiman, M. A.; Rachmawati, D.

2017-12-01

The security of the widely-used RSA public key cryptography algorithm depends on the difficulty of factoring a big integer into two large prime numbers. For many years, the integer factorization problem has been intensively and extensively studied in the field of number theory. As a result, a lot of deterministic algorithms such as Euler’s algorithm, Kraitchik’s, and variants of Pollard’s algorithms have been researched comprehensively. Our study takes a rather uncommon approach: rather than making use of intensive number theories, we attempt to factorize RSA modulus n by using random-restart hill-climbing algorithm, which belongs the class of metaheuristic algorithms. The factorization time of RSA moduli with different lengths is recorded and compared with the factorization time of Pollard’s rho algorithm, which is a deterministic algorithm. Our experimental results indicates that while random-restart hill-climbing algorithm is an acceptable candidate to factorize smaller RSA moduli, the factorization speed is much slower than that of Pollard’s rho algorithm.

Two fern species new to New Hampshire, with comments on the generation of calcareous-like habitat by base-poor rocks

Science.gov (United States)

Scott W. Bailey

2013-01-01

Incidental to other field investigations, I happened upon small populations of two fern species not previously reported from New Hampshire: Pellaea atropurpurea (L.) Link and Dryopteris filix-mas (L.) Schott. Both species are typically associated with calcareous habitats, although limestone and marble are nearly absent from New...

Cyathea arjae Latiff (Cyatheaceae), A New Species of Dwarf Tree-Fern from Sayap, Mt. Kinabalu, Sabah, Malaysia

International Nuclear Information System (INIS)

Latiff, A.

2015-01-01

A dwarf tree-fern, Cyathea arjae Latiff is described as a new species from Sayap, Mt. Kinabalu, Sabah, Malaysia. This new species belongs to Schizocaena group which has basiscopic veins that originate from the costa and not from the costule. It is closely related to C. capitata in having simply pinnate fronds of which the apex is a deltoid lamina. Holttums key was modified. (author)

A life to risk: cultural differences in motivations to climb among elite male mountaineers

Science.gov (United States)

Patrick T. Maher; Tom G. Potter

2001-01-01

This study explored the cultural differences and motivations to climb of elite, male mountaineers. The purpose of the study was to first determine the motivations of elite male mountaineers and then link these motivations to the culture in which the mountaineer lives or grew up in. Five co-researchers participated in the study: two Canadians, two Americans, and one...

Breeding Systems of Three Tree Ferns : Alsophila firma (Cyatheaceae), Cyathea stipularis (Cyatheaceae), and Lophosoria quadripinnata (Lophosoriaceae)

OpenAIRE

DOUGLAS E., SOLTIS; PAMELA S., SOLTIS; ALAN R., SMITH; Department of Botany, Washington State University; Department of Botany, Washington State University; University Herbarium, University of California

1991-01-01

Breeding-system data have been available for a large number and diverse array of angiosperms for a relatively long time. In contrast, breeding systems of ferns and their allies (pteridophytes) have only recently been examined, and breeding-system data from natural populations of sporophytes are still lacking for pteridophytes representing many life-history strategies. Few studies, for example, have examined breeding systems of tropical pteridophytes, and no breeding-system data are available ...

Algunas novelas de Darío Fernández-Flórez: de Zarabanda (1944 a Alta Costura (1954. Temas escabrosos en tiempos de restricciones moralistas

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Montejo Gurruchaga, Lucía

2008-06-01

Full Text Available Dario Fernández-Flórez begins in 1944 with Zarabanda a narrative style of intellectual eroticism and inmoral atmosphere which attracted no attention. Six years later he published Lola, espejo oscuro the recollections of a high prostitute. The novel was an scandal and an immediate success. Although the topic and its treatment were odd at the time because the strict moral values which mantained Franco´s regime were ignored, the novel was published with no cuts at all. Censorship was deaf to all the voices that warned of its dangers. This had an explanation: Darío Fernández-Flórez held an important post in the Propaganda National Service. After his dismissal censors were less lenient.Darío Fernández-Flórez inicia en 1944 con Zarabanda una narrativa de erotismo intelectualizado y ambiente amoral que no tuvo ningún eco. Seis años después publicará Lola, espejo oscuro, las memorias de una prostituta de alto copete. La novela suscitó un gran escándalo y su éxito fue inmediato. Aunque el tema y su tratamiento eran inusitados en aquellos momentos porque la obra daba al traste con los estrictos valores morales que sustentaban el régimen franquista, la novela fue publicada sin recortes; la censura hizo oídos sordos a todas las voces que alertaban de su peligro. Este hecho tiene una explicación: Darío Fernández-Flórez ocupaba un cargo importante en el Servicio Nacional de Propaganda. Tras su cese, los censores serán menos benevolentes.

Heart rate response to a climber’s fall in sport climbing

OpenAIRE

Chaloupsky, David

2015-01-01

The research deals with response of heart rate to a climber’s simulated fall in a leading position when indoor climbing. Heart rate of climbers was recorded during ascents of an overhanging route in the leading position, to the given point high above the ground, followed by falling into the last protection. The length of the free fall was defined by the place of the last belay anchor, which was at the height of climber’s ankles. The length of the fall was about two meters of free fall plus th...

Reconstructed tree fern Alethopteris zeilleri (Carboniferous, Medullosales)

Energy Technology Data Exchange (ETDEWEB)

Zodrow, Erwin L. [Department of Earth Sciences, University College of Cape Breton, Sydney, Nova, Scotia (Canada B1P 6L2)

2007-01-02

From a smaller open-pit area in the roof shale of the basal Cantabrian coal seam in Sydney Coalfield, Cape Breton Island, Nova Scotia, Canada, large amounts of the pteridosperm foliage Alethopteris zeilleri (Ragot) were found. This foliage is associated with abundant, naked medullosalean axes and dichotomies of varying sizes, up to 0.80-m long, cauline structures 0.90 m and 1.3 m long, detached ovules assigned to Pachytesta incrassata Brongniart, rare male-pollen organs of the type Dolerotheca Halle, rooted tree ferns in life position, and one specimen each of a juvenile medullosalean frond and root mantle. The fossils are compression/impression-preserved, and the foliage yielded thickly cutinized cuticles with unoriented cells (57-103 by 27-57 {mu}m) in intercostal fields. Ultimate rachises, and abaxial surfaces (excluding costal fields) show a mixture of simple and complexly-branched trichomes, and two different structural bases. These, together with fractal dimensionality of curvatures of anticlinal walls in intercostal fields, have taxonomic potential for alethopterids. The finds suggest reconstructing A. zeilleri (Ragot) as a tree, 5-7 m high, that bore both P. incrassata Brongniart and Dolerotheca-type fructifications. Its habitat was low-land coastal plains in the Pennsylvanian coal swamps of ancestral Sydney Coalfield. (author)

Morphological selection in an extreme flow environment: body shape and waterfall-climbing success in the Hawaiian stream fish Sicyopterus stimpsoni.

Science.gov (United States)

Blob, Richard W; Bridges, William C; Ptacek, Margaret B; Maie, Takashi; Cediel, Roberto A; Bertolas, Morgan M; Julius, Matthew L; Schoenfuss, Heiko L

2008-12-01

Flow characteristics are a prominent factor determining body shapes in aquatic organisms, and correlations between body shape and ambient flow regimes have been established for many fish species. In this study, we investigated the potential for a brief period of extreme flow to exert selection on the body shape of juvenile climbing Hawaiian gobiid fishes. Because of an amphidromous life history, juvenile gobies that complete an oceanic larval phase return to freshwater habitats, where they become adults. Returning juveniles often must scale waterfalls (typically with the use of a ventral sucker) in order to reach the habitats they will use as adults, thereby exposing these animals to brief periods of extreme velocities of flow. Hydrodynamic theory predicts that bodies with larger suckers and with lower heights that reduce drag would have improved climbing success and, thus, be well suited to meet the demands of the flows in waterfalls. To test the potential for the flow environment of waterfalls to impose selection that could contribute to differences in body shape between islands, we subjected juvenile Sicyopterus stimpsoni to climbing trials up artificial waterfalls (∼100 body lengths) and measured differences in body shape between successful and unsuccessful climbers. Waterfalls appear to represent a significant selective barrier to these fishes, as nearly 30% failed our climbing test. However, the effects of selection on morphology were not straightforward, as significant differences in shape between successful and unsuccessful climbers did not always match hydrodynamic predictions. In both selection experiments and in adult fish collected from habitats with different prevailing conditions of flow (the islands of Hawai'i versus Kaua'i), lower head heights were associated with exposure to high-flow regimes, as predicted by hydrodynamic theory. Thus, a premium appears to be placed on the reduction of drag via head morphology throughout the ontogeny of this

Rock climbing and acute emotion regulation in patients with major depressive disorder in the context of a psychological inpatient treatment: a controlled pilot trial

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Kleinstäuber M

2017-08-01

Full Text Available Maria Kleinstäuber,1,2 Merle Reuter,3 Norbert Doll,4 Andreas J Fallgatter4 1Division of Clinical Psychology and Psychotherapy, Faculty of Psychology, Philipps University, Marburg, Germany; 2Department of Psychological Medicine, School of Medicine, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand; 3Department of Educational Psychology, Faculty of Psychology, Eberhard Karls University, Tübingen, Germany, 4Department of General Psychiatry and Psychotherapy, University Hospital for Psychiatry and Psychotherapy, Eberhard Karls University, Tübingen, Germany Background: Major depressive disorder is characterized by deficits in emotion regulation. This study examined associations between rock climbing and acute emotion regulating effects in patients with major depression. Patients and methods: In a nonrandomized, controlled study, 40 major depressive disorder inpatients were assigned to either a climbing session (n=20 or a relaxation session (n=20. Positive and negative affect, depressiveness, and coping emotions were assessed immediately before and after the session. Results: Mixed analyses of variance and covariance revealed significant time × group interaction effects for all assessed outcomes (p≤0.012: positive affect and coping emotions significantly increased and negative affect and depressiveness significantly decreased after the climbing session (1.04≤ Cohen’s d ≤1.30, in contrast to a relaxation session (0.16≤ Cohen’s d ≤0.36. Conclusion: The results show that rock climbing is associated with acute emotion regulatory effects. These findings have to be replicated with a randomized design, and future research should pay attention to possible mechanisms of rock climbing in regard to emotion regulation. Keywords: physical activity, controlled trial, relaxation, inpatient treatment

15 June 2009 - President of the Argentine Nation C. Fernández visiting ATLAS experimental area.

CERN Document Server

Maximilien Brice

2009-01-01

Tirage 1:President of the Argentine Nation, C. Fernández and Minister of Science, Technology and Innovative Production,L. Barañao Tirage 2-8:Arrival greetings Tirage 9-12:Introduction to CERN's activities by Director-General, R. Heuer Tirage 13-15:Signature of the guest book Tirage 16-25:M. Benedetti,R. Heuer and L.Barañao sit for the signature of the Agreement Tirage 26-33: Meeting with Argentinian scientists at CERN

In vivo two-photon imaging of climbing fibers plasticity after laser axotomy

Science.gov (United States)

Allegra Mascaro, A. L.; Cesare, P.; Sacconi, L.; Grasselli, G.; Mandolesi, G.; Maco, B.; Knott, G. W.; De Paola, V.; Strata, P.; Pavone, F. S.

2013-06-01

In the adult nervous system, different neuronal classes show different regenerative behavior. Although previous studies demonstrated that olivocerebellar fibers are capable of axonal regeneration in a suitable environment as a response to injury, we have hitherto no details about the real dynamics of fiber regeneration. We set up a model of singularly axotomized climbing fibers (CF) to investigate their reparative properties in the adult central nervous system (CNS) in vivo. Here we describe the approach followed to characterize the reactive plasticity after injury.

Lianas, tree ferns and understory species: indicators of conservation status in the Brazilian Atlantic Rainforest remnants, southeastern Brazil.

Science.gov (United States)

Castello, A C D; Coelho, S; Cardoso-Leite, E

2017-01-01

Indicators are applied faster and at lower costs than conventional surveys, providing quick and efficient responses that can facilitate protected areas management. Our aim was to select indicators from vegetation to monitor protected areas. For this purpose, we analyzed understory and quantified lianas and tree ferns in protected and non-protected areas, in order to find indicator species. Our study areas are located in Vale do Ribeira, southeastern São Paulo state, Brazil. One of the areas is under two protection categories (IUCN's categories II and V), and the other is a privately owned farm. Lianas with large diameters (> 13 cm) and tree ferns with great heights (> 19 m) were considered indicators of undisturbed areas (protected areas) because their growth is directly related to forest successional stage. Indicator species within the protected area were shade tolerant species, such as Bathysa australis (A.St.-Hil.) K.Schum., whereas outside the protected area were pioneer species, such as Pera glabrata (Schott) Poepp. ex Baill. e Nectandra oppositifolia Ness. All of the suggested indicators can be used in management actions, especially in protected areas, to guarantee forest maintenance and ensure fulfillment of the conservation objectives of these areas.

Lianas, tree ferns and understory species: indicators of conservation status in the Brazilian Atlantic Rainforest remnants, southeastern Brazil

Directory of Open Access Journals (Sweden)

A. C. D. Castello

Full Text Available Abstract Indicators are applied faster and at lower costs than conventional surveys, providing quick and efficient responses that can facilitate protected areas management. Our aim was to select indicators from vegetation to monitor protected areas. For this purpose, we analyzed understory and quantified lianas and tree ferns in protected and non-protected areas, in order to find indicator species. Our study areas are located in Vale do Ribeira, southeastern São Paulo state, Brazil. One of the areas is under two protection categories (IUCN's categories II and V, and the other is a privately owned farm. Lianas with large diameters (> 13 cm and tree ferns with great heights (> 19 m were considered indicators of undisturbed areas (protected areas because their growth is directly related to forest successional stage. Indicator species within the protected area were shade tolerant species, such as Bathysa australis (A.St.-Hil. K.Schum., whereas outside the protected area were pioneer species, such as Pera glabrata (Schott Poepp. ex Baill. e Nectandra oppositifolia Ness. All of the suggested indicators can be used in management actions, especially in protected areas, to guarantee forest maintenance and ensure fulfillment of the conservation objectives of these areas.

Body shape helps legged robots climb and turn in complex 3-D terrains

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Han, Yuanfeng; Wang, Zheliang; Li, Chen

Analogous to streamlined shapes that reduce drag in fluids, insects' ellipsoid-like rounded body shapes were recently discovered to be ``terradynamically streamlined'' and enhance locomotion in cluttered terrain by facilitating body rolling. Here, we hypothesize that there exist more terradynamic shapes that facilitate other modes of locomotion like climbing and turning in complex 3-D terrains by facilitating body pitching and yawing. To test our hypothesis, we modified the body shape of a legged robot by adding an elliptical and a rectangular shell and tested how it negotiated with circular and square vertical pillars. With a rectangular shell the robot always pitched against square pillars in an attempt to climb, whereas with an elliptical shell it always yawed and turned away from circular pillars given a small initial lateral displacement. Square / circular pillars facilitated pitching / yawing, respectively. To begin to reveal the contact physics, we developed a locomotion energy landscape model. Our model revealed that potential energy barriers to transition from pitching to yawing are high for angular locomotor and obstacle shapes (rectangular / square) but vanish for rounded shapes (elliptical / circular). Our study supports the plausibility of locomotion energy landscapes for understanding the rich locomotor transitions in complex 3-D terrains.

Available friction of ladder shoes and slip potential for climbing on a straight ladder.

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Chang, Wen-Ruey; Chang, Chien-Chi; Matz, Simon

2005-07-15

Straight ladder accidents are a major safety problem. As a leading cause of injuries involving straight ladders, slips at the ladder base occur when the required friction exceeds the available friction at the ladder shoe and floor interface. The objectives of this experiment were to measure the available friction at the base of a portable straight ladder in contact with a floor and to estimate the slip potential of the ladder. The results of friction measurements indicated that the measured friction coefficient on the oily surfaces differed among the six commercially available ladder shoes evaluated. A statistical model was used to compare the available friction results from the current study with the friction requirements under different climbing conditions from a previous study based on their stochastic distributions to estimate the slip potential at the base of the ladder. The results showed that different climbing conditions used in the previous study could be supported by available friction on dry surfaces. However, when the ladder was put onto oily surfaces, resulting in a significant reduction in the available friction due to contamination, slip potential was significantly increased.

Goffman Goes Rock Climbing: Using Creative Fiction to Explore the Presentation of Self in Outdoor Education

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Beames, Simon K.; Pike, Elizabeth C. J.

2008-01-01

Outdoor education literature has a recent history of examining its practice through a variety of sociological, philosophical, psychological, and anthropological lenses. Following this trend, this paper explores the face-to-face social interaction of a fictional introductory rock-climbing course. The analysis of this creative fiction draws on…

Photoproduction of hydrogen by a non-sulphur bacterium isolated from root zones of water fern Azolla pinnata

Energy Technology Data Exchange (ETDEWEB)

Singh, S.P.; Srivastava, S.C.; Pandey, K.D. (Banaras Hindu Univ., Varanasi (IN). Centre of Advanced Study in Botany)

1990-01-01

A photosynthetic bacterium Rhodopseudomonas sp. BHU strain 1 was isolated from the root zone of water fern Azolla pinnata. The bacterium was found to produce hydrogen with potato starch under phototrophic conditions. The immobilized bacterial cells showed sustained hydrogen production with a more than 4-fold difference over free cell suspensions. The data have been discussed in the light of possible utilization of relatively cheaper raw materials by non-sulphur bacteria to evolve hydrogen. (author).

Hasta siempre Profesor Manuel Fernández: Palabras en homenaje al ex Decano de la Facultad de Arquitectura y Urbanismo Dr. Arqto. Manuel Fernández Hechenleitner (1946- 2003. / Farewell, Professor Manuel Fernandez: Words in tribute to the former - Dean of the Faculty of Architecture and Planning Dr. Arqto. Manuel Fernández Hechenleitner (1946 - 2003.

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Javier de Cárdenas

2003-06-01

Full Text Available Académicos, ex alumnos y amigos de la Facultad de Arquitectura y Urbanismo de la Universidad de Chile, recuerdan la personalidad del Dr. Arquitecto Manuel Fernández Hechenleitner (1946-2003, ex Decano de la F.A.U., con motivo de su fallecimiento./Academics, ex - students and friends of the School of Architecture and Urbanism of the University of Chile, remember the personality of Dr. Manuel Fernandez Hechenleitner Architect (1946-2003, ex - Dean of the FAU, on the occasion of his death.

Arsenic speciation for the phytoremediation by the Chinese brake fern, Pteris vittata.

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Shoji, R; Yajima, R; Yano, Y

2008-01-01

Arsenic (As) speciation for the phytoremediation by the Chinese brake fern was studied. In particular, the mechanism of how plants induce compounds containing thiol (SH) and proteins by As exposure in terms of the relationship between As and phosphate uptaken into plant cells was examined. Pteris vittata callus could efficiently reduce As(V) to As(III) by the rapid introduction of reductase and synthesize thiols leading to phytochelatins production. Furthermore, Pteris vittata could control phosphate concentration in the cells corresponding to the concentration of arsenite and arsenate. To our best knowledge, this is the first report to show the mechanisms of such high As tolerance of Pteris vittata using their callus in terms of in vitro approach for the analysis of As speciation and metabolism route.

A new schizaeaceous fern, Schizaeopsis ekrtii sp nov., and its in situ spores from the Upper Cretaceous (Cenomanian) of the Czech Republic

Czech Academy of Sciences Publication Activity Database

Kvaček, J.; Dašková, Jiřina; Pátová, R.

2006-01-01

Roč. 140, 1-2 (2006), s. 51-60 ISSN 0034-6667 R&D Projects: GA ČR GA205/03/1267 Institutional research plan: CEZ:AV0Z30130516 Keywords : fern * palaeobotany * spores * Cenomanian Subject RIV: EF - Botanics Impact factor: 1.170, year: 2006

Improving patient safety: lessons from rock climbing.

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Robertson, Nic

2012-02-01

How to improve patient safety remains an intractable problem, despite large investment and some successes. Academics have argued that the root of the problem is a lack of a comprehensive 'safety culture' in hospitals. Other safety-critical industries such as commercial aviation invest heavily in staff training to develop such a culture, but comparable programmes are almost entirely absent from the health care sector. In rock climbing and many other dangerous activities, the 'buddy system' is used to ensure that safety systems are adhered to despite adverse circumstances. This system involves two or more people using simple checks and clear communication to prevent problems causing harm. Using this system as an example could provide a simple, original and entertaining way of introducing medical students to the idea that human factors are central to ensuring patient safety. Teaching the buddy system may improve understanding and acceptance of other patient safety initiatives, and could also be used by junior doctors as a tool to improve the safety of their practice. © Blackwell Publishing Ltd 2012.

Autonomous stair-climbing with miniature jumping robots.

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Stoeter, Sascha A; Papanikolopoulos, Nikolaos

2005-04-01

The problem of vision-guided control of miniature mobile robots is investigated. Untethered mobile robots with small physical dimensions of around 10 cm or less do not permit powerful onboard computers because of size and power constraints. These challenges have, in the past, reduced the functionality of such devices to that of a complex remote control vehicle with fancy sensors. With the help of a computationally more powerful entity such as a larger companion robot, the control loop can be closed. Using the miniature robot's video transmission or that of an observer to localize it in the world, control commands can be computed and relayed to the inept robot. The result is a system that exhibits autonomous capabilities. The framework presented here solves the problem of climbing stairs with the miniature Scout robot. The robot's unique locomotion mode, the jump, is employed to hop one step at a time. Methods for externally tracking the Scout are developed. A large number of real-world experiments are conducted and the results discussed.

Turning behaviors of T cells climbing up ramp-like structures are regulated by myosin light chain kinase activity and lamellipodia formation.

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Song, Kwang Hoon; Lee, Jaehyun; Jung, Hong-Ryul; Park, HyoungJun; Doh, Junsang

2017-09-14

T cells navigate diverse microenvironments to perform immune responses. Micro-scale topographical structures within the tissues, which may inherently exist in normal tissues or may be formed by inflammation or injury, can influence T cell migration, but how T cell migration is affected by such topographical structures have not been investigated. In this study, we fabricated ramp-like structures with a 5 μm height and various slopes, and observed T cells climbing up the ramp-like structures. T cells encountering the ramp-like structures exhibited MLC accumulation near head-tail junctions contacting the ramp-like structures, and made turns to the direction perpendicular to the ramp-like structures. Pharmacological study revealed that lamellipodia formation mediated by arp2/3 and contractility regulated by myosin light chain kinase (MLCK) were responsible for the intriguing turning behavior of T cells climbing the ramp-like structures. Arp2/3 or MLCK inhibition substantially reduced probability of T cells climbing sharp-edged ramp-like structures, indicating intriguing turning behavior of T cells mediated by lamellipodia formation and MLCK activity may be important for T cells to access inflamed or injured tissues with abrupt topographical changes.

ANATOMICAL-HISTOLOGICAL OBSERVATIONS CONDUCTED ON AQUATIC FERNS IN THE DANUBE DELTA

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Anca SÂRBU

2017-12-01

Full Text Available This paper analyses aquatic ferns from the genera Azolla Lam., Marsilea L. and Salvinia Séguier, which occur in the Danube Delta, Romania, and comprises a series of anatomical and histological observations of taxonomical, chorological and eco-morphological importance. The research conducted on specimens collected between 2005-2013 from the natural habitats of the Danube Delta, but also from the extra-deltaic artificial habitats have enabled: i a reconsideration of some chorological aspects regarding the species of the genus Azolla in Romania; ii a greater understanding of the adaptive plasticity relative to the factor water for the taxon Marsilea quadrifolia L. collected from natural and artificial habitats; iii the enrichment of the data regarding the structural characteristics of the taxon Salvinia natans (L. All., particularly around the adaptive elements associated with living on the surface of the water.

REE bound proteins in natural plant fern Dicranopteris dichitoma by MAA

International Nuclear Information System (INIS)

Guo, F.Q.; Wang, Y.Q.; Sun, J.X.; Chen, H.M.

1996-01-01

Biochemical techniques, including pH variation, outsalting, ultracentrifugation, gel filtration chromatography and electrophoresis, etc., have been employed together with instrumental neutron activation analysis (INAA) to study the rare earth elements (REE) bound proteins in the natural plant fern, Dicranopteris dichitoma. INAA was also used to identify whether the proteins were bound firmly with REE. The results obtained show that two REE bound proteins (RBP-I and RBP-II) have been separated. The molecular weight of RBP-I on Sephadex G-200 gel column is about 8 x 10 5 Daltons and that of RBP-II is less than 12,400 Daltons, respectively. However, SDS-PAGE of the two proteins shows that they mainly have two protein subunits with MW 14,100 and 38,700 Daltons. They are probably conjugated proteins, glycoproteins with different glyco-units. (author). 22 refs., 7 figs., 1 tab

On the static structural design of climbing robots: part 2.

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Ahmed, Ausama Hadi; Menon, Carlo

This manuscript is the second of two parts of a work investigating optimal configurations of legged climbing robots while loitering on vertical surfaces. In this Part 2, a structural analysis based on the finite element method, specifically the stiffness method, is performed to address the problem. Parameters that are investigated in this Part 2 include the inclination of both the body and the legs of the robot. Outcomes of the performed study are validated by analyzing the posture of 150 ants when loitering on vertical surfaces. The obtained validation ensures the predictions of the developed structural model are correct and can be used to identify optimal configurations of legged robots when loitering on vertical surfaces.

Improving Students’ Mastery on Simple Present Tense Through Climbing Grammar Mountain Game

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Fadilla Taslim

2016-07-01

Full Text Available This study aims to determine whether the use of Climbing Grammar Mountain Game gave significant improvement on students in learning simple present tense. Classroom action research was used in this study where the data were analyzed by using quantitative and qualitative approaches. The population of the study was the students of grade eleventh at SMPN 1 Luak 50 Kota. There were 21 students in this class. Six kinds of instruments were used to collect data, namely teaching ,scenario, observation sheet, questionnaire, test, interview, and teacher’s journal. This study ran for two cycles. In the second cycle, it was shown that there was gradual improvement from the previous cycle which changed from 64 (insufficient to 79 (sufficient of the mean score. it was more than criteria of the students’ mean score which were determined in this study and it was significant because it proved that the students enthusiasm to study simple present tense, it mean that the students liked and were not bored again so this was a motivation for them to more concentrate to study simple present tense and they could use it in daily life for communication. They understand that simple present tense is important in learning English because it is used in daily life, either in writing and spoken language. It could be concluded that Climbing Grammar Mountain Game could improve the ability of the students in class VII B of SMPN 1 Luak 50 Kota in using Simple Present Tense.

Acrostichum, a Pioneering Fern of Floodplain Areas from the Late Oligocene Sariñena Formation of the Iberian Peninsula.

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Rafael Moreno-Domínguez

Full Text Available Acrostichum is considered today an opportunistic fern in disturbed areas, which indicates the first stages of colonisation of such zones. However, in the fossil record, Acrostichum appears related to fluvio-lacustrine environments, freshwater marshes and mangrove deposits. We report here for first time fossil evidence of Acrostichum that reveals a pioneering behaviour of this fern in the colonisation of perturbed communities in Europe, which corroborates previous assumptions about the paleobiology of Acrostichum. Plant remains were collected from the Chattian (late Oligocene La Val fossil site (Estadilla, Huesca, northeastern Spain belonging to the Sariñena Formation, which mainly embraces crevasse splays, levees and floodplain deposits. Evidence shows that Acrostichum grew within the levee's vegetal community or close to/on the river banks as well as on floodplain areas and closer to/on the shores of ephemeral ponds. But most importantly, the observed co-existence of Equisetum and Acrostichum remains in the same beds indicates that such strata represent short-lived inundated terrains, e.g., floodplains where the water table was temporarily stagnant. Evidence shows wetland environments dominated by pioneering taxa, implying a pioneering role for Acrostichum during the late Oligocene in the Iberian Peninsula.

Sensor placement on Canton Tower for health monitoring using asynchronous-climb monkey algorithm

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Yi, Ting-Hua; Li, Hong-Nan; Zhang, Xu-Dong

2012-12-01

Heuristic optimization algorithms have become a popular choice for solving complex and intricate sensor placement problems which are difficult to solve by traditional methods. This paper proposes a novel and interesting methodology called the asynchronous-climb monkey algorithm (AMA) for the optimum design of sensor arrays for a structural health monitoring system. Different from the existing algorithms, the dual-structure coding method is designed and adopted for the representation of the design variables. The asynchronous-climb process is incorporated in the proposed AMA that can adjust the trajectory of each individual dynamically in the search space according to its own experience and other monkeys. The concept of ‘monkey king’ is introduced in the AMA, which reflects the Darwinian principle of natural selection and can create an interaction network to correctly guide the movement of other monkeys. Numerical experiments are carried out using two different objective functions by considering the Canton Tower in China with or without the antenna mast to evaluate the performance of the proposed algorithm. Investigations have indicated that the proposed AMA exhibits faster convergence characteristics and can generate sensor configurations superior in all instances when compared to the conventional monkey algorithm. For structures with stiffness mutation such as the Canton Tower, the sensor placement needs to be considered for each part separately.

Sensor placement on Canton Tower for health monitoring using asynchronous-climb monkey algorithm

International Nuclear Information System (INIS)

Yi, Ting-Hua; Li, Hong-Nan; Zhang, Xu-Dong

2012-01-01

Heuristic optimization algorithms have become a popular choice for solving complex and intricate sensor placement problems which are difficult to solve by traditional methods. This paper proposes a novel and interesting methodology called the asynchronous-climb monkey algorithm (AMA) for the optimum design of sensor arrays for a structural health monitoring system. Different from the existing algorithms, the dual-structure coding method is designed and adopted for the representation of the design variables. The asynchronous-climb process is incorporated in the proposed AMA that can adjust the trajectory of each individual dynamically in the search space according to its own experience and other monkeys. The concept of ‘monkey king’ is introduced in the AMA, which reflects the Darwinian principle of natural selection and can create an interaction network to correctly guide the movement of other monkeys. Numerical experiments are carried out using two different objective functions by considering the Canton Tower in China with or without the antenna mast to evaluate the performance of the proposed algorithm. Investigations have indicated that the proposed AMA exhibits faster convergence characteristics and can generate sensor configurations superior in all instances when compared to the conventional monkey algorithm. For structures with stiffness mutation such as the Canton Tower, the sensor placement needs to be considered for each part separately. (paper)

Effects of environmental changes in a stair climbing intervention: generalization to stair descent.

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Webb, Oliver J; Eves, Frank F

2007-01-01

Visual improvements have been shown to encourage stair use in worksites independently of written prompts. This study examined whether visual modifications alone can influence behavior in a shopping mall. Climbing one flight of stairs, however, will not confer health benefits. Therefore, this study also assessed whether exposure to the intervention encouraged subsequent stair use. Interrupted time-series design. Escalators flanked by a staircase on either side. Ascending and descending pedestrians (N = 81,948). Following baseline monitoring, a colorful design was introduced on the stair risers of one staircase (the target staircase). A health promotion message was superimposed later on top. The intervention was visible only to ascending pedestrians. Thus, any rise in descending stair use would indicate increased intention to use stairs, which endured after initial exposure to the intervention. Observers inconspicuously coded pedestrians' means of ascent/descent and demographic characteristics. The design alone had no meaningful impact. Addition of the message, however, increased stair climbing at the target and nontarget staircases by 190% and 52%, respectively. The message also produced a modest increase in stair descent at the target (25%) and nontarget (9%) staircases. In public venues, a message component is critical to the success of interventions. In addition, it appears that exposure to an intervention can encourage pedestrians to use stairs on a subsequent occasion.

Creating Live Interactions to Mitigate Barriers (CLIMB): A Mobile Intervention to Improve Social Functioning in People With Chronic Psychotic Disorders

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Schlosser, Danielle; Nahum, Mor

2016-01-01

Background Numerous psychosocial interventions for individuals with chronic psychotic disorders (CPD) have shown positive effects on social cognitive and functional outcome measures. However, access to and engagement with these interventions remains limited. This is partly because these interventions require specially trained therapists, are not available in all clinical settings, and have a high scheduling burden for participants, usually requiring a commitment of several weeks. Delivering interventions remotely via mobile devices may facilitate access, improve scheduling flexibility, and decrease participant burden, thus improving adherence to intervention requirements. To address these needs, we designed the Creating Live Interactions to Mitigate Barriers (CLIMB) digital intervention, which aims to enhance social functioning in people with CPD. CLIMB consists of two treatment components: a computerized social cognition training (SCT) program and optimized remote group therapy (ORGT). ORGT is an innovative treatment that combines remote group therapy with group texting (short message service, SMS). Objectives The objectives of this single-arm study were to investigate the feasibility of delivering 6 weeks of CLIMB to people with CPD and explore the initial effects on outcomes. Methods Participants were recruited, screened and enrolled via the Internet, and delivered assessments and interventions remotely using provided tablets (iPads). Participants were asked to complete 18 hours of SCT and to attend 6 remote group therapy sessions. To assess feasibility, adherence to study procedures, attrition rates, engagement metrics, and acceptability of the intervention were evaluated. Changes on measures of social cognition, quality of life, and symptoms were also explored. Results In total, 27 participants were enrolled over 12 months. Remote assessments were completed successfully on 96% (26/27) of the enrolled participants. Retention in the 6-week trial was 78% (21

Climbing plants in a temperate rainforest understorey: searching for high light or coping with deep shade?

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Valladares, Fernando; Gianoli, Ernesto; Saldaña, Alfredo

2011-08-01

While the climbing habit allows vines to reach well-lit canopy areas with a minimum investment in support biomass, many of them have to survive under the dim understorey light during certain stages of their life cycle. But, if the growth/survival trade-off widely reported for trees hold for climbing plants, they cannot maximize both light-interception efficiency and shade avoidance (i.e. escaping from the understorey). The seven most important woody climbers occurring in a Chilean temperate evergreen rainforest were studied with the hypothesis that light-capture efficiency of climbers would be positively associated with their abundance in the understorey. Species abundance in the understorey was quantified from their relative frequency and density in field plots, the light environment was quantified by hemispherical photography, the photosynthetic response to light was measured with portable gas-exchange analyser, and the whole shoot light-interception efficiency and carbon gain was estimated with the 3-D computer model Y-plant. Species differed in specific leaf area, leaf mass fraction, above ground leaf area ratio, light-interception efficiency and potential carbon gain. Abundance of species in the understorey was related to whole shoot features but not to leaf level features such as specific leaf area. Potential carbon gain was inversely related to light-interception efficiency. Mutual shading among leaves within a shoot was very low (<20 %). The abundance of climbing plants in this southern rainforest understorey was directly related to their capacity to intercept light efficiently but not to their potential carbon gain. The most abundant climbers in this ecosystem match well with a shade-tolerance syndrome in contrast to the pioneer-like nature of climbers observed in tropical studies. The climbers studied seem to sacrifice high-light searching for coping with the dim understorey light.

Identification of up-regulated genes from the metal-hyperaccumulator aquatic fern Salvinia minima Baker, in response to lead exposure.

Science.gov (United States)

Leal-Alvarado, Daniel A; Martínez-Hernández, A; Calderón-Vázquez, C L; Uh-Ramos, D; Fuentes, G; Ramírez-Prado, J H; Sáenz-Carbonell, L; Santamaría, J M

2017-12-01

Lead (Pb) is one of the most serious environmental pollutants. The aquatic fern Salvinia minima Baker is capable to hyper-accumulate Pb in their tissues. However, the molecular mechanisms involved in its Pb accumulation and tolerance capacity are not fully understood. In order to investigate the molecular mechanisms that are activated by S. minima in response to Pb, we constructed a suppression subtractive hybridization library (SSH) in response to an exposure to 40μM of Pb(NO 3 ) 2 for 12h. 365 lead-related differentially expressed sequences tags (ESTs) were isolated and sequenced. Among these ESTs, 143 unique cDNA (97 were registered at the GenBank and 46 ESTs were not registered, because they did not meet the GenBank conditions). Those ESTs were identified and classified into 3 groups according to Blast2GO. In terms of metabolic pathways, they were grouped into 29 KEGG pathways. Among the ESTs, we identified some that might be part of the mechanism that this fern may have to deal with this metal, including abiotic-stress-related transcription factors, some that might be involved in tolerance mechanisms such as ROS scavenging, membrane protection, and those of cell homeostasis recovery. To validate the SSH library, 4 genes were randomly selected from the library and analyzed by qRT-PCR. These 4 genes were transcriptionally up-regulated in response to lead in at least one of the two tested tissues (roots and leaves). The present library is one of the few genomics approaches to study the response to metal stress in an aquatic fern, representing novel molecular information and tools to understand the molecular physiology of its Pb tolerance and hyperaccumulation capacity. Further research is required to elucidate the functions of the lead-induced genes that remain classified as unknown, to perhaps reveal novel molecular mechanisms of Pb tolerance and accumulation capacity in aquatic plants. Copyright © 2017 Elsevier B.V. All rights reserved.

The aquatic fern Azolla as a natural plant-factory for ammonia removal from fish-breeding fresh wastewater.

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Carlozzi, Pietro; Padovani, Giulia

2016-05-01

This study has investigated the potential of an Azolla-Anabaena symbiosis, a marriage between the cyanobacterium Anabaena azollae and the aquatic fern (Azolla), to remove ammonia from freshwater fish breeding areas. Experiments were carried out under artificial light of 20, 70, and 140 μmol m(-2) s(-1). We investigated three different water temperatures for the growing Azolla, ranging from sub-optimal to optimal temperatures (15, 22, and 28 °C). The capability of Azolla to remove ammonia from wastewater was demonstrated, and the highest ammonia concentration tolerated by the symbiosis between Azolla-anabaena without any toxic effect on the aquatic ferns was ascertained. The shortest time taken to remove ammonia from wastes, 2.5 cm deep and at 28 °C, was 40 min. The ammonia removal rate (A RR) was both light and temperature dependent and the highest rate (6.394 h(-1)) was attained at light intensity of 140 μmol m(-2) s(-1) and at a temperature of 28 °C; the lowest (0.947 h(-1)) was achieved at 20 μmol m(-2) s(-1) and 15 °C. The depth of the fish-wastewater pool also affected the A RR with the relation between A RR and the depth being a hyperbolic function.

Arsenic in the rhizosphere soil solution of ferns.

Science.gov (United States)

Wei, Chaoyang; Zheng, Huan; Yu, Jiangping

2012-12-01

The aim of this study was to explore the evidence of arsenic hyperaccumulation in plant rhizosphere solutions. Six common fern plants were selected and grown in three types of substrate: arsenic (As) -tailings, As-spiked soil, and soil-As-tailing composites. A rhizobox was designed with an in-situ collection of soil solutions to analyze changes in the As concentration and valence as well as the pH, dissolved organic carbon (DOC) and total nitrogen (TN). Arsenite composed less than 20% of the total As, and As depletion was consistent with N depletion in the rhizosphere solutions of the various treatments. The As concentrations in the rhizosphere and non-rhizosphere solutions in the presence of plants were lower than in the respective controls without plants, except for in the As-spiked soils. The DOC concentrations were invariably higher in the rhizosphere versus non-rhizosphere solutions from the various plants; however, no significant increase in the DOC content was observed in Pteris vittata, in which only a slight decrease in pH appeared in the rhizosphere compared to non-rhizosphere solutions. The results showed that As reduction by plant roots was limited, acidification-induced solubilization was not the mechanism for As hyperaccumulation.

Morphological selection and the evaluation of potential tradeoffs between escape from predators and the climbing of waterfalls in the Hawaiian stream goby Sicyopterus stimpsoni.

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Blob, Richard W; Kawano, Sandy M; Moody, Kristine N; Bridges, William C; Maie, Takashi; Ptacek, Margaret B; Julius, Matthew L; Schoenfuss, Heiko L

2010-12-01

Environmental pressures may vary over the geographic range of a species, exposing subpopulations to divergent functional demands. How does exposure to competing demands shape the morphology of species and influence the divergence of populations? We explored these questions by performing selection experiments on juveniles of the Hawaiian goby Sicyopterus stimpsoni, an amphidromous fish that exhibits morphological differences across portions of its geographic range where different environmental pressures predominate. Juvenile S. stimpsoni face two primary and potentially opposing selective pressures on body shape as they return from the ocean to freshwater streams on islands: (1) avoiding predators in the lower reaches of a stream; and (2) climbing waterfalls to reach the habitats occupied by adults. These pressures differ in importance across the Hawaiian Islands. On the youngest island, Hawai'i, waterfalls are close to shore, thereby minimizing exposure to predators and placing a premium on climbing performance. In contrast, on the oldest major island, Kaua'i, waterfalls have eroded further inland, lengthening the exposure of juveniles to predators before migrating juveniles begin climbing. Both juvenile and adult fish show differences in body shape between these islands that would be predicted to improve evasion of predators by fish from Kaua'i (e.g., taller bodies that improve thrust) and climbing performance for fish from Hawai'i (e.g., narrower bodies that reduce drag), matching the prevailing environmental demand on each island. To evaluate how competing selection pressures and functional tradeoffs contribute to the divergence in body shape observed in S. stimpsoni, we compared selection imposed on juvenile body shape by (1) predation by the native fish Eleotris sandwicensis versus (2) climbing an artificial waterfall (∼100 body lengths). Some variables showed opposing patterns of selection that matched predictions: for example, survivors of predation had

Behavioral Repertoire Influences the Rate and Nature of Learning in Climbing: Implications for Individualized Learning Design in Preparation for Extreme Sports Participation

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Dominic Orth

2018-06-01

Full Text Available Extreme climbing where participants perform while knowing that a simple mistake could result in death requires a skill set normally acquired in non-extreme environments. In the ecological dynamics approach to perception and action, skill acquisition involves a process where the existing repertoire of behavioral capabilities (or coordination repertoire of a learner are destabilized and re-organized through practice—this process can expand the individuals affordance boundaries allowing the individual to explore new environments. Change in coordination repertoire has been observed in bi-manual coordination and postural regulation tasks, where individuals begin practice using one mode of coordination before transitioning to another, more effective, coordination mode during practice. However, individuals may also improve through practice without qualitatively reorganizing movement system components—they do not find a new mode of coordination. To explain these individual differences during learning (i.e., whether or not a new action is discovered, a key candidate is the existing coordination repertoire present prior to practice. In this study, the learning dynamics of body configuration patterns organized with respect to an indoor climbing surface were observed and the existing repertoire of coordination evaluated prior to and after practice. Specifically, performance outcomes and movement patterns of eight beginners were observed across 42 trials of practice over a 7-week period. A pre- and post-test scanning procedure was used to determine existing patterns of movement coordination and the emergence of new movement patterns after the practice period. Data suggested the presence of different learning dynamics by examining trial-to-trial performance in terms of jerk (an indicator of climbing fluency, at the individual level of analysis. The different learning dynamics (identified qualitatively included: continuous improvement, sudden improvement

High-Order Sliding Mode-Based Synchronous Control of a Novel Stair-Climbing Wheelchair Robot

OpenAIRE

Liu, Juanxiu; Wu, Yifei; Guo, Jian; Chen, Qingwei

2015-01-01

For the attitude control of a novel stair-climbing wheelchair with inertial uncertainties and external disturbance torques, a new synchronous control method is proposed via combing high-order sliding mode control techniques with cross-coupling techniques. For this purpose, a proper controller is designed, which can improve the performance of the system under conditions of uncertainties and torque perturbations and also can guarantee the synchronization of the system. Firstly, a robust high-or...

Project "Conservation, Restoration, and Development of the Juan Fernández islands, Chile" Proyecto conservación, restauración y desarrollo de las islas Juan Fernández, Chile

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JAIME G. CUEVAS

2001-12-01

Full Text Available From a scientific point of view, the Juan Fernández islands contain one of the most interesting floras of the planet. Although protected as a National Park and a World Biosphere Reserve, 400 years of human interference have left deep traces in the native plant communities. Repeated burning, overexploitation of species, and the introduction of animal and plant plagues have taken 75 % of the endemic vascular flora to the verge of extinction. In 1997, Chile's national forest service (Corporación Nacional Forestal, CONAF started an ambitious project, whose objective is the recovery of this highly complex ecosystem with a socio-ecological focus. Juan Fernández makes an interesting case, as the local people (600 persons practically live within the park, therefore impeding the exclusion of the people from any conservation program. Secondly, the relatively small size of the archipelago (100 km² permits the observation of the effects of whatever modification in the ecosystem on small scales in time and space. Thirdly, the native and introduced biota are interrelated in such a way that human-caused changes in one species population may provoke unexpected results amongst other, non-target species. The project mainly deals with the eradication or control of some animal and plant plagues, the active conservation and restoration of the flora and the inclusion of the local people in conservation planning. This article presents the park's general problems, the strategy proposed to resolve them as well as some preliminary results. This project shows the complexity of the conservation activities in practice, with diverse and complex interrelations and gaps in ecological knowledge. In this respect, the project may well serve as a model for similar programs in other placesLas islas Juan Fernández albergan una de las floras más interesantes del planeta desde el punto de vista científico. Aunque están protegidas como Parque Nacional y Reserva Mundial de la

Proyecto conservación, restauración y desarrollo de las islas Juan Fernández, Chile

OpenAIRE

CUEVAS, JAIME G.; VAN LEERSUM, GART

2001-01-01

From a scientific point of view, the Juan Fernández islands contain one of the most interesting floras of the planet. Although protected as a National Park and a World Biosphere Reserve, 400 years of human interference have left deep traces in the native plant communities. Repeated burning, overexploitation of species, and the introduction of animal and plant plagues have taken 75 % of the endemic vascular flora to the verge of extinction. In 1997, Chile's national forest service (Corporación...

La escritora Ana de Zayas y el obispo poblano Manuel Fernández de Santa Cruz

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Zayas, Concepción

2001-06-01

Full Text Available Estudio de caso sobre la relación entre el obispo de la diócesis angelopolitana, don Manuel Fernández de Santa Cruz, y doña Ana de Zayas, escritora que la Inquisición novohispana procesó por alumbrada de 1694 a 1700. Este trabajo analiza principalmente la intervención del prelado a favor de esta mujer, lo cual impidió que ella fuera condenada por el Santo Oficio de México. El artículo se basa en fuentes mexicanas y españolas.

Fluid Model of Sliding Suction Cup of Wall-climbing Robots

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Fu Zhuang

2008-11-01

Full Text Available The adhering capability, one of the most important performance indexes of wall-climbing robots(WCRs, should be taken into account when a WCR is designed. This paper proposes a novel approach for investigating the adhering characteristics of the sliding suction cup (SSCs using fluid network theory to enhance the adhering capability of WCRs. The fluid models of the SSCs of two WCRs are developed and equivalent circuits in three cases are presented. The dynamic responses of negative pressure in SSCs are obtained and validated by a set of experiments. It indicated that the theoretical analysis is reasonable and can give some valuable design criteria on the structure parameters of SSCs and control strategies of suction force of SSCs.

Is there foul play in the leaf pocket? The metagenome of floating fern Azolla reveals endophytes that do not fix N2but may denitrify

NARCIS (Netherlands)

Dijkhuizen, Laura W.; Brouwer, Paul; Bolhuis, Henk; Reichart, Gert Jan; Koppers, Nils; Huettel, Bruno; Bolger, Anthony M.; Li, Fay Wei; Cheng, Shifeng; Liu, Xin; Wong, Gane Ka Shu; Pryer, Kathleen; Weber, Andreas P.M.; Bräutigam, Andrea; Schluepmann, Henriette

2018-01-01

Dinitrogen fixation by Nostoc azollae residing in specialized leaf pockets supports prolific growth of the floating fern Azolla filiculoides. To evaluate contributions by further microorganisms, the A. filiculoides microbiome and nitrogen metabolism in bacteria persistently associated with Azolla

Ptaquiloside, the major carcinogen of bracken fern, in the pooled raw milk of healthy sheep and goats: an underestimated, global concern of food safety.

Science.gov (United States)

Virgilio, Antonella; Sinisi, Annamaria; Russo, Valeria; Gerardo, Salvatore; Santoro, Adriano; Galeone, Aldo; Taglialatela-Scafati, Orazio; Roperto, Franco

2015-05-20

Bracken fern (Pteridium aquilinum) is a worldwide plant containing toxic substances, which represent an important chemical hazard for animals, including humans. Ptaquiloside, 1, a norsesquiterpenoid glucoside, is the major carcinogen of bracken detected in the food chain, particularly in the milk from farm animals. To date, ptaquiloside has been shown in the milk of cows feeding on a diet containing bracken fern. This is the first study that shows the systematic detection of ptaquiloside, 1, and reports its direct quantitation in pooled raw milk of healthy sheep and goats grazing on bracken. Ptaquiloside, 1, was detected by a sensitive method based on the chemical conversion of ptaquiloside, 1, into bromopterosine, 4, following gas chromatography-mass spectrometry (GC-MS) analysis. The presence of ptaquiloside, 1, possibly carcinogenic to humans, in the milk of healthy animals is an unknown potential health risk, thus representing a harmful and potential global concern of food safety.

The effect of different growth regimes on the endophytic bacterial communities of the fern, Dicksonia sellowiana hook (Dicksoniaceae)

OpenAIRE

Irene de Araújo Barros; Welington Luiz Araújo; João Lúcio Azevedo

2010-01-01

Endophytic bacteria associated with the fern Dicksonia sellowiana were investigated. The bacterial communities from the surface-sterilized pinnae and rachis segments of the plants from the Brazilian Atlantic Rainforest that grew in native field conditions were compared with the bacterial communities from plants grown in greenhouses and plants that were initially grown in greenhouses and then transferred to the forest. From 540 pinnae and 540 rachis segments, 163 (30.2%) and 346 (64.2%) were c...

Design of a Robust Stair Climbing Compliant Modular Robot to Tackle Overhang on Stairs

OpenAIRE

Bhole, Ajinkya; Turlapati, Sri Harsha; S, Rajashekhar V.; Dixit, Jay; Shah, Suril V.; Krishna, K Madhava

2016-01-01

This paper discusses the concept and parameter design of a Robust Stair Climbing Compliant Modular Robot, capable of tackling stairs with overhangs. Modifying the geometry of the periphery of the wheels of our robot helps in tackling overhangs. Along with establishing a concept design, robust design parameters are set to minimize performance variation. The Grey-based Taguchi Method is adopted for providing an optimal setting for the design parameters of the robot. The robot prototype is shown...

Role of route previewing strategies on climbing fluency and exploratory movements

Science.gov (United States)

Cordier, Romain; Orth, Dominic; Courtine, Yoan; Croft, James L.

2017-01-01

This study examined the role of route previewing strategies on climbing fluency and on exploratory movements of the limbs, in order to understand whether previewing helps people to perceive and to realize affordances. Eight inexperienced and ten experienced climbers previewed a 10 m high route of 5b difficulty on French scale, then climbed it with a top-rope as fluently as possible. Gaze behavior was collected from an eye tracking system during the preview and allowed us to determine the number of times they scanned the route, and which of four route previewing strategies (fragmentary, ascending, zigzagging, and sequence-of-blocks) they used. Five inertial measurement units (IMU) (3D accelerometer, 3D gyroscope, 3D magnetometer) were attached to the hip, both feet, and forearms to analyze the vertical acceleration and direction of each limb and hip during the ascent. We were able to detect movement and immobility phases of each IMU using segmentation and classification processes. Depending on whether the limbs and/or hip were moving, five states of behavior were detected: immobility, postural regulation, hold exploration, hold change, and hold traction. Using cluster analysis we identified four clusters of gaze behavior during route previewing depending on route preview duration, number of scan paths, fixations duration, ascending, zigzagging, and sequence-of-blocks strategies. The number of scan paths was positively correlated with relative duration of exploration and negatively correlated with relative duration of hold changes during the ascent. Additionally, a high relative duration of sequence-of-blocks strategy and zigzagging strategy were associated with a high relative duration of immobility during the ascent. Route previewing might help to pick up functional information about reachable, graspable, and usable holds, in order to chain movements together and to find the route. In other words, route previewing might contribute to perceiving and realizing nested

Role of route previewing strategies on climbing fluency and exploratory movements.

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Ludovic Seifert

Full Text Available This study examined the role of route previewing strategies on climbing fluency and on exploratory movements of the limbs, in order to understand whether previewing helps people to perceive and to realize affordances. Eight inexperienced and ten experienced climbers previewed a 10 m high route of 5b difficulty on French scale, then climbed it with a top-rope as fluently as possible. Gaze behavior was collected from an eye tracking system during the preview and allowed us to determine the number of times they scanned the route, and which of four route previewing strategies (fragmentary, ascending, zigzagging, and sequence-of-blocks they used. Five inertial measurement units (IMU (3D accelerometer, 3D gyroscope, 3D magnetometer were attached to the hip, both feet, and forearms to analyze the vertical acceleration and direction of each limb and hip during the ascent. We were able to detect movement and immobility phases of each IMU using segmentation and classification processes. Depending on whether the limbs and/or hip were moving, five states of behavior were detected: immobility, postural regulation, hold exploration, hold change, and hold traction. Using cluster analysis we identified four clusters of gaze behavior during route previewing depending on route preview duration, number of scan paths, fixations duration, ascending, zigzagging, and sequence-of-blocks strategies. The number of scan paths was positively correlated with relative duration of exploration and negatively correlated with relative duration of hold changes during the ascent. Additionally, a high relative duration of sequence-of-blocks strategy and zigzagging strategy were associated with a high relative duration of immobility during the ascent. Route previewing might help to pick up functional information about reachable, graspable, and usable holds, in order to chain movements together and to find the route. In other words, route previewing might contribute to perceiving and

Phylogeny and systematics of the brake fern genus Pteris (Pteridaceae) based on molecular (plastid and nuclear) and morphological evidence.

Science.gov (United States)

Zhang, Liang; Zhang, Li-Bing

2018-01-01

The brake fern genus Pteris belongs to Pteridaceae subfamily Pteridoideae. It is one of the largest fern genera and has been estimated to contain 200-250 species distributed on all continents except Antarctica. Previous studies were either based on plastid data only or based on both plastid and nuclear data but the sampling was small. In addition, an infrageneric classification of Pteris based on morphological and molecular evidence has not been available yet. In the present study, based on molecular data of eight plastid markers and one nuclear marker (gapCp) of 256 accessions representing ca. 178 species of Pteris, we reconstruct a global phylogeny of Pteris. The 15 major clades identified earlier are recovered here and we further identified a new major clade. Our nuclear phylogeny recovered 11 of these 16 major clades, seven of which are strongly supported. The inclusion of Schizostege in Pteris is confirmed for the first time. Based on the newly reconstructed phylogeny and evidence from morphology, distribution and/or ecology, we classify Pteris into three subgenera: P. subg. Pteris, P. subg. Campteria, and P. subg. Platyzoma. The former two are further divided into three and 12 sections, respectively. Copyright © 2017 Elsevier Inc. All rights reserved.

Paloma Fernández Gomá: latidos de poesía que unen orillas

OpenAIRE

Medrano, Susana de los Ángeles

2010-01-01

En la lírica española contemporánea ya no cabe duda de que la poesía de mujer constituye un aporte significativo. Dentro de su entramado, en la panorámica actual de la lírica femenina de Andalucía, Paloma Fernández Gomá se perfila como una de las poetas más interesantes y singulares. Nacida en Madrid y asentada en Algeciras (Cádiz) desde niña, su poesía se inicia tempranamente pero recién se da a conocer en 1991 con El ocaso del girasol, al que le siguen hasta el momento una decena de poemari...

The fossil Osmundales (Royal Ferns)-a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes.

Science.gov (United States)

Bomfleur, Benjamin; Grimm, Guido W; McLoughlin, Stephen

2017-01-01

The Osmundales (Royal Fern order) originated in the late Paleozoic and is the most ancient surviving lineage of leptosporangiate ferns. In contrast to its low diversity today (less than 20 species in six genera), it has the richest fossil record of any extant group of ferns. The structurally preserved trunks and rhizomes alone are referable to more than 100 fossil species that are classified in up to 20 genera, four subfamilies, and two families. This diverse fossil record constitutes an exceptional source of information on the evolutionary history of the group from the Permian to the present. However, inconsistent terminology, varying formats of description, and the general lack of a uniform taxonomic concept renders this wealth of information poorly accessible. To this end, we provide a comprehensive review of the diversity of structural features of osmundalean axes under a standardized, descriptive terminology. A novel morphological character matrix with 45 anatomical characters scored for 15 extant species and for 114 fossil operational units (species or specimens) is analysed using networks in order to establish systematic relationships among fossil and extant Osmundales rooted in axis anatomy. The results lead us to propose an evolutionary classification for fossil Osmundales and a revised, standardized taxonomy for all taxa down to the rank of (sub)genus. We introduce several nomenclatural novelties: (1) a new subfamily Itopsidemoideae (Guaireaceae) is established to contain Itopsidema , Donwelliacaulis , and Tiania ; (2) the thamnopteroid genera Zalesskya , Iegosigopteris , and Petcheropteris are all considered synonymous with Thamnopteris ; (3) 12 species of Millerocaulis and Ashicaulis are assigned to modern genera (tribe Osmundeae); (4) the hitherto enigmatic Aurealcaulis is identified as an extinct subgenus of Plenasium ; and (5) the poorly known Osmundites tuhajkulensis is assigned to Millerocaulis . In addition, we consider Millerocaulis

Survival and growth of epiphytic ferns depend on resource sharing

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Hua-Zheng eLu

2016-03-01

Full Text Available Locally available resources can be shared within clonal plant systems through physiological integration, thus enhancing their survival and growth. Most epiphytes exhibit clonal growth habit, but few studies have tested effects of physiological integration (resource sharing on survival and growth of epiphytes and whether such effects vary with species. We conducted two experiments, one on individuals (single ramets and another on groups (several ramets within a plot, with severed and intact rhizome treatments (without and with physiological integration on two dominant epiphytic ferns (Polypodiodes subamoena and Lepisorus scolopendrium in a subtropical montane moist forest in Southwest China. Rhizome severing (preventing integration significantly reduced ramet survival in the individual experiment and number of surviving ramets in the group experiment, and it also decreased biomass of both species in both experiments. However, the magnitude of such integration effects did not vary significantly between the two species. We conclude that resource sharing may be a general strategy for clonal epiphytes to adapt to forest canopies where resources are limited and heterogeneously distributed in space and time.

A comparison of the dietary arsenic exposures from ingestion of contaminated soil and hyperaccumulating Pteris ferns used in a residential phytoremediation project.

Science.gov (United States)

Ebbs, Stephen; Hatfield, Sarah; Nagarajan, Vinay; Blaylock, Michael

2010-01-01

Arsenic (As) hyperaccumulating ferns are used to phytoremediate As-contaminated soils, including soils in residential areas. This use may pose a health risk if children were to ingest these plants. Spider brake (Pteris cretica L.) plants were grown in sand spiked with arsenate, to produce tissue As concentrations (2000-4500 mg kg DW(-1)) typical of those observed in plants deployed for As phytoremediation. The fronds were subjected to a physiologically-based extraction test to estimate As bioaccessibility, which ranged from 3.4-20.5%. A scenario for human dietary exposure to As in an urban setting was then estimated for a child consuming 0.25 g DW of tissue. The calculation of dietary exposure took into account the As concentration in the fern pinnae, the bioaccessibility of As in the tissue, and the typical absorption of inorganic As by the gastrointestinal tract. The pinnae As concentrations and the calculated dietary exposures were used to create a non-linear regression model relating tissue As concentration to dietary exposure. Data from a phytoremediation project in a residential area using Pteris cretica and Pteris vittata (L.) were input into this model to project dietary As exposure in a residential phytoremediation setting. These exposures were compared to estimates of dietary As exposure from the consumption of soil. The results showed that dietary exposures to As from consumption of soil or pinnae tissue were similar and that estimates of dietary exposure were below the LOAEL value of 14 microg As kg(-1) d(-1). The results suggest that the hyperaccumulation of As in Pteris ferns during growth in moderately contaminated residential soils (e.g., < or = 100 mg As kg DW(-1)) does not represent an inherent risk or a risk substantially different from that posed by accidental ingestion of contaminated soil.

Fernández Álvarez: compromiso y rigor de un modernista

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Francisco CHACÓN JIMÉNEZ

2011-07-01

Full Text Available Es difícil sintetizar toda una trayectoria vital de setenta años de dedicación completa a la Historia. Los titulares de prensa en el día de su fallecimiento le calificaban de: «César y Hombre de la Historia de España»; «el historiador con lírica»; «el iluminador de la Historia de España»; «el historiador por excelencia de la España del Siglo de Oro»; «gran investigador y catedrático ejemplar»; «el biógrafo de España»; «el gran divulgador de nuestro pasado». Son algunos de los titulares de prensa que el pasado 20 de abril de 2010 anunciaban el fallecimiento del insigne historiador. En realidad la síntesis de todas ellas anuncia el significado, la personalidad y el ejemplo de lo que fue y quiso ser Manuel Fernández Álvarez.

Thiol synthesis and arsenic hyperaccumulation in Pteris vittata (Chinese brake fern)

International Nuclear Information System (INIS)

Zhang Weihua; Cai Yong; Downum, Kelsey R.; Ma, Lena Q.

2004-01-01

Pteris vittata (Chinese brake fern) has potential for phytoremediation of As-contaminated sites. In this study, the synthesis of total thiols and acid-soluble thiols in P. vittata was investigated under arsenic exposure. The strong and positive correlation between As concentration and acid-soluble thiols in plant leaflets suggests that acid-soluble thiols may play a role in As detoxification. A major As-induced thiol was purified and characterized. A molecular ion (M+1) of 540 m/z suggests that the thiol was a phytochelatin (PC) with two base units (PC 2 ). However, the ratios of acid-soluble thiols to As in leaflets exposed to As ranged from 0.012 to 0.026, suggesting that only a very small part of As is complexed by PC 2 . PCs could play a minor detoxification role in this hyperaccumulator. A PC-independent mechanism appears to be mainly involved in As tolerance, while PC-dependent detoxification seems to be a supplement

Thiol synthesis and arsenic hyperaccumulation in Pteris vittata (Chinese brake fern)

Energy Technology Data Exchange (ETDEWEB)

Zhang Weihua; Cai Yong; Downum, Kelsey R.; Ma, Lena Q

2004-10-01

Pteris vittata (Chinese brake fern) has potential for phytoremediation of As-contaminated sites. In this study, the synthesis of total thiols and acid-soluble thiols in P. vittata was investigated under arsenic exposure. The strong and positive correlation between As concentration and acid-soluble thiols in plant leaflets suggests that acid-soluble thiols may play a role in As detoxification. A major As-induced thiol was purified and characterized. A molecular ion (M+1) of 540 m/z suggests that the thiol was a phytochelatin (PC) with two base units (PC{sub 2}). However, the ratios of acid-soluble thiols to As in leaflets exposed to As ranged from 0.012 to 0.026, suggesting that only a very small part of As is complexed by PC{sub 2}. PCs could play a minor detoxification role in this hyperaccumulator. A PC-independent mechanism appears to be mainly involved in As tolerance, while PC-dependent detoxification seems to be a supplement.

Benito Fernández de Elena Garro: una mirada crítica sobre la historia mexicana

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Gerardo Bustamante Bermúdez

2017-07-01

Full Text Available En 1957, Elena Garro escribió la obra teatral Benito Fernández, texto en el que hace una revisión crítica a la historia nacional, el poder, la simulación y la búsqueda de la identidad personal en medio de la sociedad creada a partir de la posrevolución mexicana. La obra de la escritora es un contradiscurso a la oficialidad, a la mitificación de los hechos y héroes nacionales; lo que le interesa es resaltar el carácter racista y clasista de una nueva sociedad de dirigentes políticos en busca del bienestar personal y de grupo por encima del bien colectivo, para ello, opta porque en su obra los personajes se preocupen por comprar una cabeza, es decir, una ideología que les haga saber que existen. In 1957, Elena Garro wrote the play Benito Fernández, a text in which she critically reviews Mexico's national history, issues of power, simulation and the quest for personal identity in the midst of a society emerged in the after effects of the Mexican Revolution. This work is a counter-discourse to Mexico's official narrative and the idealization of facts and national heroes. She is interested in the racist and classist aspects of the new dominating society, which is interested in their own personal welfare over those of the collective. To do so, she makes her characters concerned about buying a head, that is, an ideology to fundament their own existence.

Identification and Characterization of TALE Homeobox Genes in the Endangered Fern Vandenboschia speciosa.

Science.gov (United States)

Ruiz-Estévez, Mercedes; Bakkali, Mohammed; Martín-Blázquez, Rubén; Garrido-Ramos, Manuel A

2017-10-17

We report and discuss the results of a quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis of the expression patterns of seven three amino acid loop extension ( TALE ) homeobox genes (four KNOTTED-like homeobox ( KNOX ) and three BEL1-like homeobox ( BELL ) genes) identified after next generation sequencing (NGS) and assembly of the sporophyte and gametophyte transcriptomes of the endangered fern species Vandenboschia speciosa . Among the four KNOX genes, two belonged to the KNOX1 class and the other two belonged to the KNOX2 class. Analysis of the deduced amino acid sequences supported the typical domain structure of both types of TALE proteins, and the homology to TALE proteins of mosses, lycophytes, and seed plant species. The expression analyses demonstrate that these homeodomain proteins appear to have a key role in the establishment and development of the gametophyte and sporophyte phases of V. speciosa lifecycle, as well as in the control of the transition between both phases. Vandenboschia speciosa VsKNAT3 (a KNOX2 class protein) as well as VsBELL4 and VsBELL10 proteins have higher expression levels during the sporophyte program. On the contrary, one V. speciosa KNOX1 protein (VsKNAT6) and one KNOX2 protein (VsKNAT4) seem important during the development of the gametophyte phase. TALE homeobox genes might be among the key regulators in the gametophyte-to-sporophyte developmental transition in regular populations that show alternation of generations, since some of the genes analyzed here ( VsKNAT3 , VsKNAT6 , VsBELL4 , and VsBELL6 ) are upregulated in a non-alternating population in which only independent gametophytes are found (they grow by vegetative reproduction outside of the range of sporophyte distribution). Thus, these four genes might trigger the vegetative propagation of the gametophyte and the repression of the sexual development in populations composed of independent gametophytes. This study represents a comprehensive

A MODULAR DESIGN OF A WALL-CLIMBING ROBOT AND ITS MECHATRONICS CONTROLLER

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N.S. Tlale

2012-01-01

Full Text Available

ENGLISH ABSTRACT: The modular design of a wall-climbing robot, implementing two articulated legs per module (biped robotic modules, is presented in this paper. Modular design improves a wall-climbing robot’s manoeuvrability and flexibility during surface changes or while walking on uneven surfaces. The design of the articulated legs uses four motors to control the posture of the vacuum cups, achieving the best possible contact with the surface. Each leg can contain more than five sensors for effective feedback control, and additional sensors such as gyros, CCD sensors, etc, can be fitted on a module, depending on the robot’s application. As the number of modules used in the design of the robot is increased, the number of actuators and sensors increases exponentially. A distributed mechatronics controller of such systems is presented.

AFRIKAANSE OPSOMMING: Modulêre ontwerp van 'n muurklim-robot met twee geskarnierde bene per module (twee-benige robotmodules word in hierdie artikel weergegee. Modulêre ontwerp verbeter die muurklim-robot se beweeglikheid en aanpasbaarheid tydens veranderings in die loopvlak of terwyl dit loop op ongelyke oppervlaktes. Ontwerp van geskarnierde bene implementeer vier motors wat die oriëntasie van vakuumsuigdoppe beheer om die bes moontlike kontak met die loopvlak te handhaaf. Elke been kan meer as vyf sensors hê vir doeltreffende terugvoerbeheer, en bykomende sensors soos giroskope, CCD sensors, ens. kan by 'n module gevoeg word soos die toepassing van die robot dit mag vereis. Soos die aantal modules wat in die ontwerp van die robot gebruik word, toeneem, neem die aantal aktiveerders en sensors eksponensiëel toe. 'n Verdeelde megatroniese beheerder van sulke stelsels word aangebied.

Tree Climbing Techniques and Volume Equations for Eschweilera (Matá-Matá, a Hyperdominant Genus in the Amazon Forest

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Bruno O. Gimenez

2017-05-01

Full Text Available The Eschweilera genus has great ecological and economic importance due to its wide abundance in the Amazon basin. One potential use for the Eschweilera genus is in forest management, where just a few trees are removed per hectare. In order to improve the forest management in the Amazon, this study assessed two critical issues: volume equations fitted for a single genus and the development of a non-destructive method using climbing techniques. The equipment used to measure the sample trees included: climbing rope, ascenders, descenders, and carabiners. To carry out the objectives of this study, 64 trees with diameter at breast height (DBH ≥ 10 cm were selected and measured in ZF-2 Tropical Forestry Station near the city of Manaus, Brazil. Four single input models with DBH and four dual input models with DBH and merchantable height (H were tested. The Husch model (V = a × DBHb presented the best performance (R2 = 0.97. This model does not require the merchantable height, which is an important advantage, because of the difficulty in measuring this variable in tropical forests. When the merchantable height data are collected using accurate methods, the Schumacher and Hall model (V = a × DBHb × Hc is the most appropriated. Tree climbing techniques with the use of ropes, as a non-destructive method, is a good alternative to measure the merchantable height, the diameter along the stem, and also estimate the tree volume (m3 of the Eschweilera genus in the Amazon basin.

Study on REE bound proteins in natural plant fern dicranopteris dichotomy by MAA

International Nuclear Information System (INIS)

Guo Fanqing; Wang Yuqi; Sun Jingxing; Chen Hongmin; Xu Lei; Cao Guoyin

1997-01-01

Biochemical techniques, including pH variation, outsalting, ultracentrifugation, gel filtration chromatography and electrophoresis, etc., have been employed together with instrumental neutron activation analysis (INAA) to study the rare earth elements (REE) bound proteins in the natural plant fern, Dicranopteris dichotomy. INAA was also used to identify whether the proteins were bound firmly with REE. The results obtained show that two REE bound proteins (RBP-I and RBP-II) have been separated. The molecular mass (molecular weight, MW) of RBP-I on Sephadex G-200 gel column is about 8 x 10 5 and that of RBP-II is less than 12400, respectively. However, SDS-PAGE of the two proteins shows that they mainly have two protein subunits with MW 14100 and 38700. They are probably conjugated proteins, glycoproteins with different glycol-units

Analysis of automobile’s automatic control systems for the hill climbing start

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Valeriy I. Klimenko

2014-12-01

Full Text Available To improve road safety while driving on the rise, facilitating the driver’s activity the automobile industry leaders are introducing automatic hill-hold control systems into the car design. This study purpose relates to the existing automatic start control systems’ design analysis. Analyzed are the existing design developments of automatic hill start assist control systems applied for driving at the start of the climbing. The effected research allows to select the scheme for further development of start driving automatic control systems. Further improvement of driving control systems and primarily the driver assistance hill-hold control systems is necessary to increase both the driving comfort and the traffic safety.

Stair Climbing Control for 4-DOF Tracked Vehicle Based on Internal Sensors

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Daisuke Endo

2017-01-01

Full Text Available In search-and-rescue missions, multi-degrees-of-freedom (DOF tracked robots that are equipped with subtracks are commonly used. These types of robots have superior locomotion performance on rough terrain. However, in teleoperated missions, the performance of tracked robots depends largely on the operators’ ability to control every subtrack appropriately. Therefore, an autonomous traversal function can significantly help in the teleoperation of such robots. In this paper, we propose a planning and control method for 4-DOF tracked robots climbing up/down known stairs automatically based on internal sensors. Experimental results obtained using mockup stairs verify the effectiveness of the proposed method.

Rapid allopolyploid radiation of moonwort ferns (Botrychium; Ophioglossaceae) revealed by PacBio sequencing of homologous and homeologous nuclear regions.

Science.gov (United States)

Dauphin, Benjamin; Grant, Jason R; Farrar, Donald R; Rothfels, Carl J

2018-03-01

Polyploidy is a major speciation process in vascular plants, and is postulated to be particularly important in shaping the diversity of extant ferns. However, limitations in the availability of bi-parental markers for ferns have greatly limited phylogenetic investigation of polyploidy in this group. With a large number of allopolyploid species, the genus Botrychium is a classic example in ferns where recurrent polyploidy is postulated to have driven frequent speciation events. Here, we use PacBio sequencing and the PURC bioinformatics pipeline to capture all homeologous or allelic copies of four long (∼1 kb) low-copy nuclear regions from a sample of 45 specimens (25 diploids and 20 polyploids) representing 37 Botrychium taxa, and three outgroups. This sample includes most currently recognized Botrychium species in Europe and North America, and the majority of our specimens were genotyped with co-dominant nuclear allozymes to ensure species identification. We analyzed the sequence data using maximum likelihood (ML) and Bayesian inference (BI) concatenated-data ("gene tree") approaches to explore the relationships among Botrychium species. Finally, we estimated divergence times among Botrychium lineages and inferred the multi-labeled polyploid species tree showing the origins of the polyploid taxa, and their relationships to each other and to their diploid progenitors. We found strong support for the monophyly of the major lineages within Botrychium and identified most of the parental donors of the polyploids; these results largely corroborate earlier morphological and allozyme-based investigations. Each polyploid had at least two distinct homeologs, indicating that all sampled polyploids are likely allopolyploids (rather than autopolyploids). Our divergence-time analyses revealed that these allopolyploid lineages originated recently-within the last two million years-and thus that the genus has undergone a recent radiation, correlated with multiple independent

Using combined measurements for comparison of light induction of stomatal conductance, electron transport rate and CO2 fixation in woody and fern species adapted to different light regimes.

Science.gov (United States)

Wong, Shau-Lian; Chen, Chung-Wei; Huang, Hsien-Wen; Weng, Jen-Hsien

2012-05-01

We aimed to understand the relation of photosynthetic rate (A) with g(s) and electron transport rate (ETR) in species of great taxonomic range and light adaptation capability during photosynthetic light induction. We studied three woody species (Alnus formosana, Ardisia crenata and Ardisia cornudentata) and four fern species (Pyrrosia lingus, Asplenium antiquum, Diplazium donianum and Archangiopteris somai) with different light adaptation capabilities. Pot-grown materials received 100 and/or 10% sunlight according to their light adaptation capabilities. At least 4 months after light acclimation, CO(2) and H(2)O exchange and chlorophyll fluorescence were measured simultaneously by equipment in the laboratory. In plants adapted or acclimated to low light, dark-adapted leaves exposed to 500 or 2000 µmol m(-2) s(-1) photosynthetic photon flux (PPF) for 30 min showed low gross photosynthetic rate (P(g)) and short time required to reach 90% of maximum P(g) (). At the initiation of illumination, two broad-leaved understory shrubs and the four ferns, especially ferns adapted to heavy shade, showed higher stomatal conductance (g(s)) than pioneer tree species; materials with higher g(s) had short at both 500 and 2000 µmol m(-2) s(-1) PPF. With 500 or 2000 µmol m(-2) s(-1) PPF, the g(s) for the three woody species increased from 2 to 30 min after the start of illumination, but little change in the g(s) of the four ferns. Thus, P(g) and g(s) were not correlated for all material measured at the same PPF and induction time. However, P(g) was positively correlated with ETR, even though CO(2) assimilation may be influenced by stomatal, biochemical and photoinhibitory limitations. In addition, was closely related to time required to reach 90% maximal ETR for all materials and with two levels of PPF combined. Thus, ETR is a good indicator for estimating the light induction of photosynthetic rate of species, across a wide taxonomic range and light adaptation and acclimation

Climbing Mont Blanc - A Training Site for Energy Efficient Programming on Heterogeneous Multicore Processors

OpenAIRE

Natvig, Lasse; Follan, Torbjørn; Støa, Simen; Magnussen, Sindre; Guirado, Antonio Garcia

2015-01-01

Climbing Mont Blanc (CMB) is an open online judge used for training in energy efficient programming of state-of-the-art heterogeneous multicores. It uses an Odroid-XU3 board from Hardkernel with an Exynos Octa processor and integrated power sensors. This processor is three-way heterogeneous containing 14 different cores of three different types. The board currently accepts C and C++ programs, with support for OpenCL v1.1, OpenMP 4.0 and Pthreads. Programs submitted using the graphical user in...

The fossil Osmundales (Royal Ferns)—a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes

Science.gov (United States)

2017-01-01

The Osmundales (Royal Fern order) originated in the late Paleozoic and is the most ancient surviving lineage of leptosporangiate ferns. In contrast to its low diversity today (less than 20 species in six genera), it has the richest fossil record of any extant group of ferns. The structurally preserved trunks and rhizomes alone are referable to more than 100 fossil species that are classified in up to 20 genera, four subfamilies, and two families. This diverse fossil record constitutes an exceptional source of information on the evolutionary history of the group from the Permian to the present. However, inconsistent terminology, varying formats of description, and the general lack of a uniform taxonomic concept renders this wealth of information poorly accessible. To this end, we provide a comprehensive review of the diversity of structural features of osmundalean axes under a standardized, descriptive terminology. A novel morphological character matrix with 45 anatomical characters scored for 15 extant species and for 114 fossil operational units (species or specimens) is analysed using networks in order to establish systematic relationships among fossil and extant Osmundales rooted in axis anatomy. The results lead us to propose an evolutionary classification for fossil Osmundales and a revised, standardized taxonomy for all taxa down to the rank of (sub)genus. We introduce several nomenclatural novelties: (1) a new subfamily Itopsidemoideae (Guaireaceae) is established to contain Itopsidema, Donwelliacaulis, and Tiania; (2) the thamnopteroid genera Zalesskya, Iegosigopteris, and Petcheropteris are all considered synonymous with Thamnopteris; (3) 12 species of Millerocaulis and Ashicaulis are assigned to modern genera (tribe Osmundeae); (4) the hitherto enigmatic Aurealcaulis is identified as an extinct subgenus of Plenasium; and (5) the poorly known Osmundites tuhajkulensis is assigned to Millerocaulis. In addition, we consider Millerocaulis stipabonettiorum a

Phylogeny and character evolution of the fern genus Tectaria (Tectariaceae) in the Old World inferred from chloroplast DNA sequences.

Science.gov (United States)

Ding, Hui-Hui; Chao, Yi-Shan; Callado, John Rey; Dong, Shi-Yong

2014-11-01

In this study we provide a phylogeny for the pantropical fern genus Tectaria, with emphasis on the Old World species, based on sequences of five plastid regions (atpB, ndhF plus ndhF-trnL, rbcL, rps16-matK plus matK, and trnL-F). Maximum parsimony, maximum likelihood, and Bayesian inference are used to analyze 115 individuals, representing ca. 56 species of Tectaria s.l. and 36 species of ten related genera. The results strongly support the monophyly of Tectaria in a broad sense, in which Ctenitopsis, Hemigramma, Heterogonium, Psomiocarpa, Quercifilix, Stenosemia, and Tectaridium should be submerged. Such broadly circumscribed Tectaria is supported by the arising pattern of veinlets and the base chromosome number (x=40). Four primary clades are well resolved within Tectaria, one from the Neotropic (T. trifoliata clade) and three from the Old World (T. subtriphylla clade, Ctenitopsis clade, and T. crenata clade). Tectaria crenata clade is the largest one including six subclades. Of the genera previously recognized as tectarioid ferns, Ctenitis, Lastreopsis, and Pleocnemia, are confirmed to be members in Dryopteridaceae; while Pteridrys and Triplophyllum are supported in Tectariaceae. To infer morphological evolution, 13 commonly used characters are optimized on the resulting phylogenetic trees and in result, are all homoplastic in Tectaria. Copyright © 2014 Elsevier Inc. All rights reserved.

Distribution patterns of ferns and lycophytes in the Coastal Region of the state of Rio Grande do Sul, Brazil

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Felipe Gonzatti

2016-01-01

Full Text Available ABSTRACT A survey of ferns and lycophytes of the Coastal Region of the state of Rio Grande do Sul (CRRS was performed based on field work and collections of the main regional herbaria. The following were evaluated for each species: preferential habits (terrestrial, epiphytic or aquatic, geographic distribution patterns and habitats (forest, grassland, and wetland. The occurrence of a latitudinal gradient in diversity was tested over five latitudinal ranges using the Sørensen Similarity Index. A total of 17 lycophyte and 206 fern species representing 28 families was found between the latitudes of 29° and 34°S. Exclusively terrestrial species were predominant (162, with the majority (113 exhibiting wide Neotropical distributions, followed by species that also occurred in the state of Paraná (44. The forest habitat harbored the greatest number of species (159, while grasslands had the fewest (26. Cluster analysis showed pronounced floristic differentiation among latitudinal Ranges III (31°01' to 32°S and IV (32°01' to 31°S, with a similarity index of only 0.41. Our results demonstrate a strong north-to-south reduction in species richness in the study area, which is related to environmental conditions along the latitudinal gradient and, especially, microclimatic differences in the transition zone between the Atlantic Forest and Pampa biomes.

Fertile organs and in situ spores of a new dipteridaceous fern Hausmannia sinensis from the Jurassic of northern China.

Science.gov (United States)

Wang, Yongdong; Zhang, Hong

2010-01-22

As a representative fossil member of the dipteridaceous fern, genus Hausmannia was reported worldwide from the Mesozoic strata; however, little is known about the fertile structures, including sporangia and in situ spores, of this genus. In this study, a new species Hausmannia sinensis was identified from the Middle Jurassic of Nei Mongol (Inner Mongolia), northern China. The specimens are compressions and are well preserved with details of sporangia and in situ spores. The leaf laminae are broadly fan-shaped, with an almost entire margin. Primary and lateral veins dichotomously branch to form square or polygonal meshes. Each ultimate mesh bears one to two circular sori of 0.4 mm in diameter. Sori are exindusiate; each sorus contains three to six round to ovoid sporangia. The annulus is developed and oblique, with stomial region present in proximal position. Spores are trilete, circular to oval in shape. Both proximal and distal surfaces are covered with baculate to subverrucate sculptures. Spores range from 20 to 30 microm in diameter (average 28 microm), and are comparable to the dispersed genera Baculatisporites Thomas and Pflug and Apiculatisporis Potonié and Kremp. Hausmannia sinensis represents the first compression species of genus Hausmannia form Eurasia, which shows the combination of well-preserved sori, sporangia, annuli and in situ spore characters, and is therefore helpful for further understanding the diversity and evolution of the Dipteridaceae fern lineage through time.

Design and Optimal Research of a Non-Contact Adjustable Magnetic Adhesion Mechanism for a Wall-Climbing Welding Robot

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Minghui Wu

2013-01-01

Full Text Available Wall-climbing welding robots (WCWRs can replace workers in manufacturing and maintaining large unstructured equipment, such as ships. The adhesion mechanism is the key component of WCWRs. As it is directly related to the robot's ability in relation to adsorbing, moving flexibly and obstacle-passing. In this paper, a novel non-contact adjustably magnetic adhesion mechanism is proposed. The magnet suckers are mounted under the robot's axils and the sucker and wall are in non-contact. In order to pass obstacles, the sucker and the wheel unit can be pulled up and pushed down by a lifting mechanism. The magnetic adhesion force can be adjusted by changing the height of the gap between the sucker and the wall by the lifting mechanism. In order to increase the adhesion force, the value of the sucker's magnetic energy density (MED is maximized by optimizing the magnet sucker's structure parameters with a finite element method. Experiments prove that the magnetic adhesion mechanism has enough adhesion force and that the WCWR can complete wall-climbing work within a large unstructured environment.

Effective Pneumatic Scheme and Control Strategy of a Climbing Robot for Class Wall Cleaning on High-rise Buildings

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Guanghua Zong

2008-11-01

Full Text Available A new kind of pneumatic climbing robot is presented to meet the requirements of glass-wall cleaning for high-rise buildings, which is totally actuated by pneumatic cylinders and attached to the glass wall with vacuum suckers. Using the pneumatic actuators the climbing robot can be made lightweight and dexterous. At the same time the movement driven by pneumatic actuators has the characteristic of passive compliance. In order to solve the problems of high speed movement for the Y cylinder and precise position control of the X cylinder, the applied pneumatic schemes of X and Y cylinders are employed to drive the high-speed on-off solenoid valves and an ordinary valve to adjust the air-flow and pressure to the cylinders. Furthermore a method of segment and variable bang-bang controller is proposed to implement the accurate control of the position servo system for the X cylinder during the sideways movement. Testing results show that the novel approach can effectively improve the control quality. This cleaning robot can meet the requirements of realization.

Effective Pneumatic Scheme and Control Strategy of a Climbing Robot for Class Wall Cleaning on High-rise Buildings

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Houxiang Zhang

2006-06-01

Full Text Available A new kind of pneumatic climbing robot is presented to meet the requirements of glass-wall cleaning for high-rise buildings, which is totally actuated by pneumatic cylinders and attached to the glass wall with vacuum suckers. Using the pneumatic actuators the climbing robot can be made lightweight and dexterous. At the same time the movement driven by pneumatic actuators has the characteristic of passive compliance. In order to solve the problems of high speed movement for the Y cylinder and precise position control of the X cylinder, the applied pneumatic schemes of X and Y cylinders are employed to drive the high-speed on-off solenoid valves and an ordinary valve to adjust the air-flow and pressure to the cylinders. Furthermore a method of segment and variable bang-bang controller is proposed to implement the accurate control of the position servo system for the X cylinder during the sideways movement. Testing results show that the novel approach can effectively improve the control quality. This cleaning robot can meet the requirements of realization.

Impacts of environmental factors on the climbing behaviors of herbaceous stem-twiners.

Science.gov (United States)

Hu, Liang; Chen, Youfang; Liu, Meicun

2017-11-01

The curvature of the helical trajectory formed by herbaceous stem-twiners has been hypothesized to be constant on uniformly sized cylindrical supports and remains constant on different supports varying in diameter. However, experimental studies on the constant curvature hypothesis have been very limited. Here, we tested the hypothesis in a series of experiments on five herbaceous stem-twiners ( Ipomoea triloba , Ipomoea nil , Phaseolus vulgaris , Vigna unguiculata, and Mikania micrantha ). We investigated how internode characteristics (curvature [β], diameter [ d ], and length [ L ]) and success rate (SR) of twining shoots would be affected by support thickness ( D ), temperature ( T ), illumination, and support inclination. The results showed that: (1) the SR of tested species decreased, but d increased with increasing support thickness. The β of the twining shoots on erect cylindrical poles was not constant, but it decreased with increasing d or support thickness. (2) The SR of tested species was not obviously reduced under low-temperature conditions, but their β was significantly higher and d significantly lower when temperature was more than 5°C lower. (3) The SR , d, and L of two tested Ipomoea species significantly declined, but β increased under 50% shading stress. (4) The curvatures of upper semicycles of I. triloba shoots on 45° inclined supports were not significantly different from curvatures of those shoots climb on erect supports, whereas the curvatures of lower semicycles were 40%-72% higher than curvatures of upper semicycles. Synthesis : Our study illustrates that stem curvatures of a certain herbaceous stem-twiners are not constant, but rather vary in response to external support, temperature, and illumination conditions. We speculate that herbaceous stem-twiners positively adapt to wide-diameter supports by thickening their stems and by reducing their twining curvatures. This insight helps us better understand climbing processes and

Toxicity of Diclofenac in the Fern Azolla filiculoides and the Lichen Xanthoria parietina.

Science.gov (United States)

Vannini, Andrea; Paoli, Luca; Vichi, Marco; Bačkor, Martin; Bačkorová, Miriam; Loppi, Stefano

2018-03-01

This study investigated the occurrence of toxicity, expressed as damage to the photosynthetic apparatus, in the aquatic fern Azolla filiculoides and the lichen Xanthoria parietina following treatments with diclofenac at different concentrations (0.1, 1, 10 and 100 mg/L) and different exposure times (24, 48, 72 and 240 h). Measurements of photosynthetic efficiency, chlorophyll content and chlorophyll degradation indicated dose- and time-dependent toxicity, since significant differences with control samples as well as among treatments, emerged mainly for the highest concentration (100 mg/L) and the longest time (240 h). In addition, also the mycobiont of the lichen X. parietina showed similar toxic effects, expressed as ergosterol content. The absence of relevant alterations at the lowest concentration (0.1 mg/L) suggested a very limited susceptibility of these species to environmentally relevant levels of this pharmaceutical.

Developing and Deploying an XML-based Learning Content Management System at the FernUniversität Hagen

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Gerd Steinkamp

2005-02-01

Full Text Available This paper is a report about the FuXML project carried out at the FernUniversität Hagen. FuXML is a Learning Content Management System (LCMS aimed at providing a practical and efficient solution for the issues attributed to authoring, maintenance, production and distribution of online and offline distance learning material. The paper presents the environment for which the system was conceived and describes the technical realisation. We discuss the reasons for specific implementation decisions and also address the integration of the system within the organisational and technical infrastructure of the university.

Optimal Design of a New Wheeled Mobile Robot by Kinetic Analysis for the Stair-Climbing States

OpenAIRE

Woo, Chun-Kyu; Choi, Hyun Do; Kim, Mun Sang; Kim, Soo Hyun; Kwak, Yoon Keun

2007-01-01

In order to be utilized in building inspection, building security, and military reconnaissance, a new type of WMR was designed with a passive linkage-type locomotive mechanism for improved adaptability to rough terrain and stair-climbing without the active control techniques. Two designed concepts, `adaptability' and `passivity', were considered for the design of the linkage-type locomotive mechanism of the WMR. The proposed mechanism, composed of a simple 4-bar linkage mechanism and a limite...

Sobre hipermetrías y un estrofa con seis versos en el “Libro de Fernán Gonçález”

OpenAIRE

Veiga, Alexandre

2011-01-01

El autor reflexiona sobre ciertos versos añadidos a estrofas del Libro de Fernán Gonçález como razonablemente debidos a la intervención de un recitador, de cuya memorización del poema procedería el texto de la única copia que se conserva. El autor procede a la relectura crítica de la estrofa 674/686.

Paleomycology of the Princeton Chert. III. Dictyosporic microfungi, Monodictysporites princetonensis gen. et sp. nov., associated with decayed rhizomes of an Eocene semi-aquatic fern.

Science.gov (United States)

Klymiuk, Ashley A

2016-09-01

This study builds on previous investigations of paleomycological diversity within permineralized plants of a significant Eocene paleobotanical locality, the Princeton Chert. The fungal body fossils described here occur in decayed rhizomes of the extinct semi-aquatic fern Dennstaedtiopsis aerenchymata Fungi include vegetative hyphae throughout the plant tissue, as well as a dense assemblage of >100 dematiaceous spores. The spores occur in a discrete zone surrounding two extraneous rootlets of other plants, which penetrated the fern tissue post-mortem. Spores are obovoid and muriform, composed of 8-12 cells with constricted septa and produced from hyaline or slightly pigmented hyphae. The spores are morphologically similar to both asexual reproductive dictyospores of phylogenetically disparate microfungi attributed to the morphogenus Monodictys and perennating dictyochlamydospores that occur in the anamorph genus Phoma In addition to expanding the early Eocene fossil record for Ascomycota, these specimens also provide new insight into the rapidity of initial phases of the fossilization process in this important paleobotanical locality. © 2016 by The Mycological Society of America.

Cultivo de Cattleya Lindley (Orchidaceae em substratos alternativos ao xaxim = Alternative substrates for Cattleya (Orchidaceae cultivation to substitute the tree fern fiber

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Jorge Kaoro Yamakami

2006-10-01

Full Text Available Este trabalho teve como objetivo avaliar substratos alternativos ao xaxim no cultivo de um híbrido de Cattleya Lindley. Os substratos avaliados foram: xaxim; fibra de coco; casca de pínus + casca de arroz carbonizada (1:1v/v; casca de pínus+casca de arroz carbonizada (2:1v/v; casca de pínus+casca de arroz carbonizada (1:2v/v; casca de pínus e casca de arroz carbonizada. As mudas foram cultivadas em vasos de polipropileno, permanecendo em viveiro com 70% de luminosidade Os parâmetros avaliados um ano após o início do experimento foram: massa de matéria fresca total, altura da parte aérea, comprimento do pseudobulbo, comprimento da maior raiz, número de raízes, número de brotos, número de flores, pH e condutividade elétrica. O substrato constituído de fibra de coco proporcionou bons resultados, podendo ser considerado alternativo ao xaxim no cultivo deCattleya.The objective of this study was to evaluate alternative substrates tosubstitute tree fern fiber for cultivation of hybrids from the Cattleya species. Seedlings were cultivated in polypropylene vases, kept in screen shadowed nursery by a 70% of lighting. The following substrates were evaluated: tree fern fibers; coconut fiber; pinus bark+carbonized rice hull (1:1 v/v; pinus bark+carbonized rice hull (2:1 v/v; pinus bark+carbonized rice hull (1:2 v/v; pinus bark and carbonized rice hull. One year after the experiment, the followingparameters were evaluated: fresh matter mass, aerial part height, pseudobulb length, greater root length, number of buds, number of flowers, pH and electric conductivity. The substrate composed of coconut fiber showed better results, and can be used as the alternative substrate to tree fern fiber in the cultivation of Cattleya.

Dynamics of a thermally driven film climbing the outside of a vertical cylinder.

Science.gov (United States)

Smolka, Linda B

2017-10-01

The dynamics of a film climbing the outside of a vertical cylinder under the competing effects of a thermally driven surface tension gradient and gravity is examined through numerical simulations of a thin-film model for the film height. The model, including boundary conditions, depends on three parameters, the scaled cylinder radius R[over ̂], the upstream film height h_{∞}, and the downstream precursor film thickness b, and reduces to the model for Marangoni driven film climbing a vertical plate in the limit R[over ̂]→∞. The axisymmetric advancing front displays dynamics similar to that found along a vertical plate where, depending on h_{∞}, the film forms a single Lax shock, an undercompressive double shock, or a rarefaction-undercompressive shock. A linear stability analysis of the Lax shock reveals the number of fingers that form along the contact line increases linearly with cylinder circumference while no fingers form for sufficiently small cylinders (below R[over ̂]≈1.15 when b=0.1). The substrate curvature controls the height of the Lax shock, bounds on h_{∞} that define the three distinct solutions, and the maximum growth rate of contact line perturbations to the Lax shock when R[over ̂]=O(1), whereas the three solutions and the stability of the Lax shock converge to the behavior one observes on a vertical plate when R[over ̂]≥O(10). An energy analysis reveals that the azimuthal curvatures of the base state and perturbation, which arise from the annular geometry of the film, promote instability of the advancing contact line.

Transgressive intimacy in the fiction of Costamagna, Fernández, Jeftanovic, Maturana and Meruane

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Nan Zheng

2017-11-01

Full Text Available The present work, framed primarily in the discourse of intimacy, Jacques Rancière’s theory of the aesthetic regime of art and Wendy Brow's revision of Foucault's reflecctions on Neoliberalism, examines the chilean fictions of the last two decades by Alejandra Costamagna, Nona Fernández, Andrea Jeftanovic, Andrea Maturana and Lina Meruane. The literary production of these female writers disagrees with patriarchal norms and those established by the neoliberal rationality dominated by the homo oeconomicus. This article analyzes the possibility of classifying these writers as a new literary generation of the post-dictatorship, which could be more inconvenient than benefical, since it would represent a gesture which could be establishing divisions between feminine and masculine; private and public; the sublime in art and the banality of everyday life.

Metabolic adaptation, a specialized leaf organ structure and vascular responses to diurnal N2 fixation by nostoc azollae sustain the astonishing productivity of azolla ferns without nitrogen fertilizer

NARCIS (Netherlands)

Brouwer, Paul; Bräutigam, Andrea; Buijs, Valerie A.; Tazelaar, Anne O.E.; van der Werf, Adrie; Schlüter, Urte; Reichart, Gert-Jan; Bolger, Anthony; Usadel, Björn; Weber, Andreas P.M.; Schluepmann, Henriette

2017-01-01

Sustainable agriculture demands reduced input of man-made nitrogen (N) fertilizer, yet N2 fixation limits the productivity of crops with heterotrophic diazotrophic bacterial symbionts. We investigated floating ferns from the genus Azolla that host phototrophic diazotrophic Nostoc azollae in leaf

μ-XRF imaging and μ-XANES analysis of root of arsenic hyperaccumulator fern (Pteris vittata L.) by using synchrotron radiation

International Nuclear Information System (INIS)

Kitajima, Nobuyuki; Onuma, Ryoko; Hokura, Akiko; Nakai, Izumi; Terada, Yasuko

2006-01-01

Pteris vittata L. is known as a peculiar fern which have high performance to accumulate arsenic, a toxic heavy metal, in its plant body. This fern is expected as a strong candidate plant for a technology of phytoremediation due to its hyperaccumulation ability (over 2% arsenic concentration with dry weight basis). In this study, the distribution of arsenic in a horizontal cross-section of root was examined by μ-SR-XRF imaging, and a valence change from surface to centre of the root was revealed by the As-K edge μ-XANES spectra. All the measurements were carried out utilizing X-ray microbeam (1.1 μm x 1.3 μm) from the undulator source at BL37XU in SPring-8 (JASRI, Japan). Arsenic was detected on whole area of root tissue from surface to centre, and mainly distributed within the structure through a cell wall. A comparison of XANES spectra of the 8 points in the root tissue at high As level with those of the reference compounds (As 2 O 3 and H 3 AsO 4 ), revealed that As (V) uptaken by root was reduced to As (III) immediately, and existed as a mixture of As (III) and As (V). Furthermore, it was indicated that their ratios As (III)/As (V) increased remarkably at the boundary area between the cortex and the central cylinder. (author)

Aero-Propulsive Model Design from a Commercial Aircraft in Climb and Cruise Regime using Performance Data =

Science.gov (United States)

Tudor, Magdalena

IATA has estimated, in 2012, at about 2% of global carbon dioxide emissions, the environmental impact of the air transport, as a consequence caused by the rapidly growing of global movement demand of people and goods, and which was effectively taken into account in the development of the aviation industry. The historic achievements of scientific and technical progress in the field of commercial aviation were contributed to this estimate, and even today the research continues to make progress to help to reduce the emissions of greenhouse gases. Advances in commercial aircraft, and its engine design technology had the aim to improve flight performance. These improvements have enhanced the global flight planning of these types of aircrafts. Almost all of these advances rely on generated performance data as reference sources, the most of which are classified as "confidential" by the aircraft manufacturers. There are very few aero-propulsive models conceived for the climb regime in the literature, but none of them was designed without access to an engine database, and/or to performance data in climb and in cruise regimes with direct applicability for flight optimization. In this thesis, aero-propulsive models methodologies are proposed for climb and cruise regimes, using system identification and validation methods, through which airplane performance can be computed and stored in the most compact and easily accessible format for this kind of performance data. The acquiring of performance data in this format makes it possible to optimize flight profiles, used by on-board Flight Management Systems. The aero-propulsive models developed here were investigated on two aircrafts belonging to commercial class, and both of them had offered very good accuracy. One of their advantages is that they can be adapted to any other aircraft of the same class, even if there is no access to their corresponding engine flight data. In addition, these models could save airlines a considerable

Role of glutathione in tolerance to arsenite in Salvinia molesta, an aquatic fern

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Adinan Alves da Silva

2017-09-01

Full Text Available ABSTRACT In many plant species, tolerance to toxic metals is highly dependent on glutathione, an essential metabolite for cellular detoxification. We evaluated the responses of glutathione metabolism to arsenite (AsIII in Salvinia molesta, an aquatic fern that has unexplored phytoremediation potential. Plants were exposed to different AsIII concentrations in nutrient solution for 24 h. AsIII caused cell membrane damage to submerged leaves, indicating oxidative stress. There was an increase in the glutathione content and ϒ-glutamylcysteine synthetase enzyme activity in the submerged and floating leaves. The glutathione peroxidase and glutathione sulfotransferase enzymes also showed increased activity in both plant parts, whereas glutathione reductase only showed increased activity in the submerged leaves. These findings suggest an important role for glutathione in the protection of S. molesta against the toxic effects of AsIII, with more effective tolerance responses in the floating leaves.

Rock paintings in Fern Cave, Lava Beds National Monument, California: Not the 1054 A.D. (Crab Nebula) Supernova

International Nuclear Information System (INIS)

Armitage, R.A.; Hyman, M.; Rowe, M. W.

1997-01-01

On July 4, 1054 A.D. a supernova brighter than Venus appeared in the sky, remaining visible for approximately 23 days and 650 nights. It was chronicled in five independent historic accounts, four in China and one in Japan. For at least 40 years investigators have attributed certain distinctive rock paintings and carvings in the western United States as recordings of the 1054 A.D. supernova. More than twenty such depictions (circle or star-like symbols and a crescent) have been located. Two panels of rock paintings in Lava Beds National Monument, California, one at Fern Cave and one at Symbol Bridge, were listed as recording the 1054 A.D. supernova. The only direct means of assessing the likelihood that a 'supernova' representation records the 1054 A.D. event is to date the rock painting or carving. At Texas A and M University, was developed a plasma-chemical extraction technique that permits to analyze the 14 C in rock paintings, whether the pigments used were charcoal or inorganic Fe- and Mn- oxides and hydroxides with organic binder/vehicles. This paper presents direct 14 C age estimates on a rock painting suggested to represent the 1054 A.D. supernova. Charcoal pigment samples were collected from three figures in proximity at Fern Cave: a crescent pointing downward and two nearby circles, one above and one below the crescent. The AMS 14 C analysis on each sample using this technique show that these images do not represent the 1054 A.D. supernova

A Circuit for Gradient Climbing in C. elegans Chemotaxis

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Johannes Larsch

2015-09-01

Full Text Available Animals have a remarkable ability to track dynamic sensory information. For example, the nematode Caenorhabditis elegans can locate a diacetyl odor source across a 100,000-fold concentration range. Here, we relate neuronal properties, circuit implementation, and behavioral strategies underlying this robust navigation. Diacetyl responses in AWA olfactory neurons are concentration and history dependent; AWA integrates over time at low odor concentrations, but as concentrations rise, it desensitizes rapidly through a process requiring cilia transport. After desensitization, AWA retains sensitivity to small odor increases. The downstream AIA interneuron amplifies weak odor inputs and desensitizes further, resulting in a stereotyped response to odor increases over three orders of magnitude. The AWA-AIA circuit drives asymmetric behavioral responses to odor increases that facilitate gradient climbing. The adaptation-based circuit motif embodied by AWA and AIA shares computational properties with bacterial chemotaxis and the vertebrate retina, each providing a solution for maintaining sensitivity across a dynamic range.

Reduction of GABA/sub B/ receptor binding induced by climbing fiber degeneration in the rat cerebellum

International Nuclear Information System (INIS)

Kato, K.; Fukuda, H.

1985-01-01

When the rat cerebellar climbing fibers degenerated, as induced by lesioning the inferior olive with 3-acetylpyridine (3-AP), GABA/sub B/ receptor binding determined with 3 H-(+/-)baclofen was reduced in the cerebellum but not in the cerebral cortex of rats. Computer analysis of saturation data revealed two components of the binding sites, and indicated that decrease of the binding in the cerebellum was due to reduction in receptor density, mainly of the high-affinity sites, the B/sub max/ of which was reduced to one-third that in the control animals. In vitro treatment with 3-AP, of the membranes prepared from either the cerebellum or the cerebral cortex, induced no alteration in the binding sites, thereby indicating that the alteration of GABA/sub B/ sites induced by in vivo treatment with 3-AP is not due to a direct action of 3-AP on the receptor. GABA/sub A/ and benzodiazepine receptor binding labelled with 3 H-muscimol and 3 H-diazepam, respectively, in both of brain regions was not affected by destruction of the inferior olive. These results provide evidence that some of the GABA/sub B/ sites but neither GABA/sub A/ nor benzodiazepine receptors in the cerebellum are located at the climbing fiber terminals. 28 references, 4 figures, 2 tables

CLIMB (the Cloud Infrastructure for Microbial Bioinformatics): an online resource for the medical microbiology community.

Science.gov (United States)

Connor, Thomas R; Loman, Nicholas J; Thompson, Simon; Smith, Andy; Southgate, Joel; Poplawski, Radoslaw; Bull, Matthew J; Richardson, Emily; Ismail, Matthew; Thompson, Simon Elwood-; Kitchen, Christine; Guest, Martyn; Bakke, Marius; Sheppard, Samuel K; Pallen, Mark J

2016-09-01

The increasing availability and decreasing cost of high-throughput sequencing has transformed academic medical microbiology, delivering an explosion in available genomes while also driving advances in bioinformatics. However, many microbiologists are unable to exploit the resulting large genomics datasets because they do not have access to relevant computational resources and to an appropriate bioinformatics infrastructure. Here, we present the Cloud Infrastructure for Microbial Bioinformatics (CLIMB) facility, a shared computing infrastructure that has been designed from the ground up to provide an environment where microbiologists can share and reuse methods and data.

High gene flow in epiphytic ferns despite habitat loss and fragmentation.

Science.gov (United States)

Winkler, Manuela; Koch, Marcus; Hietz, Peter

2011-01-01

Tropical montane forests suffer from increasing fragmentation and replacement by other types of land-use such as coffee plantations. These processes are known to affect gene flow and genetic structure of plant populations. Epiphytes are particularly vulnerable because they depend on their supporting trees for their entire life-cycle. We compared population genetic structure and genetic diversity derived from AFLP markers of two epiphytic fern species differing in their ability to colonize secondary habitats. One species, Pleopeltis crassinervata , is a successful colonizer of shade trees and isolated trees whereas the other species, Polypodium rhodopleuron , is restricted to forests with anthropogenic separation leading to significant isolation between populations. By far most genetic variation was distributed within rather than among populations in both species, and a genetic admixture analysis did not reveal any clustering. Gene flow exceeded by far the benchmark of one migrant per generation to prevent genetic divergence between populations in both species. Though populations are threatened by habitat loss, long-distance dispersal is likely to support gene flow even between distant populations, which efficiently delays genetic isolation. Consequently, populations may rather be threatened by ecological consequences of habitat loss and fragmentation.

Field observations of climbing behavior and seed predation by adult ground beetles (Coleoptera: Carabidae) in a lowland area of the temperate zone.

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Sasakawa, Kôji

2010-10-01

Granivory is a specialized food habit in the predominantly carnivorous beetle family Carabidae. Most studies of carabid granivory have been conducted under laboratory conditions; thus, our knowledge of the feeding ecology of granivorous carabids in the field is insufficient. I conducted field observations of climbing behavior and seed predation by adult carabids in a lowland area of eastern Japan, from early October to late November in 2008. This is the first systematic field observation of the feeding ecology of granivorous carabids in the temperate zone. In total, 176 carabid individuals of 11 species were observed, with 108 individuals feeding on plant seeds/flowers. Each carabid species was primarily observed feeding on a particular plant species. Frequently observed combinations were: Amara gigantea Motschulsky on Humulus scandens (Loureiro) Merrill (Moraceae) seed, Amara lucens Baliani on Artemisia indica Willdenow (Asteraceae) flower, and Amara macronota (Solsky) and Harpalus (Pseudoophonus) spp. on Digitaria ciliaris (Retzius) Koeler (Poaceae) seed. In all but one species, the sex ratio of individuals observed feeding was female-biased. In Am. gigantea and Am. macronota, a larger proportion of females than males ate seeds. In the three Amara species, copulations on plants, with the female feeding on its seeds/flowers, were often observed. These observations may indicate that, whereas females climb onto plants to feed on seeds, males climb to seek females for copulation rather than forage. Because granivorous carabids play important roles as weed-control agents in temperate agro-ecosystems, the present results would provide valuable basic information for future studies on this subject.

Leaf allocation patterns and 13C and 15N natural abundances of tropical lianas (Passiflora sp.) as dependent on external climbing support.

Science.gov (United States)

Werth, Martin; Spiegel, Ann-Kathrin; Kazda, Marian

2013-01-01

The transformation from self-supporting lianas to host-supported climbing lianas is related to re-allocation of biomass and nutrients among plant organs. Therefore, first, variations in leaf mass per area (LMA), leaf carbon and nitrogen allocation and (13)C and (15)N natural abundances were analysed among three tropical Passiflora species (P. edulis, P. ligularis, and P. tripartita) in a greenhouse study. Second, the influence of a climbing support was considered for each species and parameter. P. ligularis leaves were most enriched in (13)C in both treatments when compared with the other two species. This enrichment was caused by a high LMA, which is related to a high internal resistance to CO(2) diffusion. For P. edulis and P. tripartita, δ(13)C was additionally increasing with nitrogen content per area. Generally, there were no differences when considering carbon and nitrogen allocation to leaves of host-supported and self-supporting lianas. The only hints towards increased investment into leaves after the transition from self-supporting to host-supported stages could be seen by a trend to increased leaf areas and masses. δ(13)C values of supported P. edulis or P. tripartita plants were significantly increasing faster than those of non-supported plants once the interactions of leaf mass or nitrogen content per area were accounted for. Hence, the offer of a climbing support had only a minor impact on δ(13)C or δ(15)N values in vitro, but this could be different with increasing age of lianas in vivo.

El primer registro de Simón Fernández de Moya, escribano público de Cuenca. 1423

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Francisco Antonio Chacón Gómez-Monedero

2005-01-01

Full Text Available El estudio y publicación de los registros notariales de la Edad Media proporciona interesante información sobre aspectos sociales de los habitantes de cualquier población. En este trabajo estudiamos el primer registro que confeccionó el escribano Simón Fernández de Moya, investido de la «fieles pública» por el Concejo de Cuenca en sesión municipal de 7 de mayo de 1423. Se presta especial atención a los dos aspectos básicos que interesan al diplomatista: el de los caracteres externos e internos, según la tipología diplomática de los negocios que fedata el «auctor». Ante la imposibilidad material de transcribir el Registro hemos optado por regestar los asientos, acompañados de un índice onomástico.The publication of the present article shows the importance of notarial records in the Middie Ages and how they provide interested Information about social issues of the inhabitants of whichever town. On this review, it is studied the first record elaborated by Simón Fernández de Moya who was invested with «fieles publica» by the Council of Cuenca at municipal session on 7th May 1423. Two aspects can be taken into account by the diplomatist: the external and the infernal characters according to the typificatlon of Diplomatic about business. Because of the material imposibility to transcribe completely the record book, the present essay only summarize all seats as well as an Índex of ñames.

Development and characterization of 27 microsatellite markers for the mangrove fern, Acrostichum aureum (Pteridaceae).

Science.gov (United States)

Yamamoto, Takashi; Tsuda, Yoshiaki; Mori, Gustavo Maruyama; Cruz, Mariana Vargas; Shinmura, Yoshimi; Wee, Alison K S; Takayama, Koji; Asakawa, Takeshi; Yamakawa, Takeru; Suleiman, Monica; Núñez-Farfán, Juan; Webb, Edward L; Watano, Yasuyuki; Kajita, Tadashi

2016-09-01

Twenty-seven nuclear microsatellite markers were developed for the mangrove fern, Acrostichum aureum (Pteridaceae), to investigate the genetic structure and demographic history of the only pantropical mangrove plant. Fifty-six A. aureum individuals from three populations were sampled and genotyped to characterize the 27 loci. The number of alleles and expected heterozygosity ranged from one to 15 and 0.000 to 0.893, respectively. Across the 26 polymorphic loci, the Malaysian population showed much higher levels of polymorphism compared to the other two populations in Guam and Brazil. Cross-amplification tests in the other two species from the genus determined that seven and six loci were amplifiable in A. danaeifolium and A. speciosum, respectively. The 26 polymorphic microsatellite markers will be useful for future studies investigating the genetic structure and demographic history of of A. aureum, which has the widest distributional range of all mangrove plants.

El Cura Juan Fernández de Sotomayor y Picón y los catecismos de la Independencia

OpenAIRE

Ocampo López, Javier

2010-01-01

Este libro presenta el entorno revolucionario de finales del siglo XVIII y primera mitad del siglo XIX, a través del pensamiento y la acción del cura cartagenero Juan Fernández de Sotomayor y Picón, Cura de Mompós y rector del colegio Mayor de Nuestra Señora del Rosario, quien vivió en los años que dieron nacimiento a la República de Colombia. Se desempeñó como cura revolucionario, como político de Mompós, de Cartagena de Indias, ante el Congreso de las Provincias Unidas del Congreso Nacional...

Modelación de la conectividad de las subpoblaciones de la langosta de Juan Fernández (Jasus frontalis, a través de un modelo biofísico Modeling the connectivity of Juan Fernández rock lobster (Jasus frontalis, subpopulations through a biophysical model

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Javier Porobic

2012-09-01

Full Text Available El archipiélago de Juan Fernández y el de las islas Desventuradas, corresponden a dos pequenos grupos de islas oceánicas, separadas entre sí 460 mn y ubicadas aproximadamente a 360 mn frente a la costa chilena. La economía local de estas islas se basa casi exclusivamente en la extracción y comercialización de recursos marinos, focalizados principalmente en la explotación de la langosta (Jasusfrontalis. Esta especie endémica se encuentra distribuída en ambos archipiélagos conformando una metapoblación, donde su dinámica y estructura poblacional sería modulada por forzantes oceanográficos, especialmente durante su prolongada fase larval planctónica. Se evaluó la estructura poblacional y el grado de conectividad-retención dentro y entre las diferentes islas mediante el uso de modelos biofísicos acoplados (modelos hidrodinámicos provenientes del modelo OFES y un modelo individuo basado de J. frontalis. El análisis de los resultados del modelo hidrodinámico indica la presencia de estructuras de mesoescala asociadas al sistema de islas. Índices provenientes del modelo biofísico muestran niveles importantes de conectividad-retención dentro y entre los sistemas de islas y una fuerte variación interanual de estos. Los resultados de la modelación biofísica indican que la varibilidad en el reclutamiento asociado al archipiélago de Juan Fernández depende mayoritariamente de larvas originadas en este mismo sistema, con un aporte importante de reclutas hacia el archipiélago de las Desventuradas. Se realizaron estudios de sensibilidad del modelo biofísico para identificar forzantes potenciales de las variables dependientes del modelo (e.g. índices de conectividad-retención, resultando en que los patrones temporales y espaciales reproductivos, la duración del estadio larval y la temporada (ano son altamente significativos. Finalmente, se propone que J. frontalis presenta una estructura metapoblacional con un alto nivel de

Proteomic analysis of stipe explants reveals differentially expressed proteins involved in early direct somatic embryogenesis of the tree fern Cyathea delgadii Sternb.

Science.gov (United States)

Domżalska, Lucyna; Kędracka-Krok, Sylwia; Jankowska, Urszula; Grzyb, Małgorzata; Sobczak, Mirosław; Rybczyński, Jan J; Mikuła, Anna

2017-05-01

Using cyto-morphological analysis of somatic embryogenesis (SE) in the tree fern Cyathea delgadii as a guide, we performed a comparative proteomic analysis in stipe explants undergoing direct SE. Plant material was cultured on hormone-free medium supplemented with 2% sucrose. Phenol extracted proteins were separated using two-dimensional gel electrophoresis (2-DE) and mass spectrometry was performed for protein identification. A total number of 114 differentially regulated proteins was identified during early SE, i.e. when the first cell divisions started and several-cell pro-embryos were formed. Proteins were assigned to seven functional categories: carbohydrate metabolism, protein metabolism, cell organization, defense and stress responses, amino acid metabolism, purine metabolism, and fatty acid metabolism. Carbohydrate and protein metabolism were found to be the most sensitive SE functions with the greatest number of alterations in the intensity of spots in gel. Differences, especially in non-enzymatic and structural protein abundance, are indicative for cell organization, including cytoskeleton rearrangement and changes in cell wall components. The highest induced changes concern those enzymes related to fatty acid metabolism. Global analysis of the proteome reveals several proteins that can represent markers for the first 16days of SE induction and expression in fern. The findings of this research improve the understanding of molecular processes involved in direct SE in C. delgadii. Copyright © 2017 Elsevier B.V. All rights reserved.

The reversion phenomenon in irradiated fern prothalli: Effects of acute or chronic anoxia and let

International Nuclear Information System (INIS)

Hendry, J.H.; Cowie, F.G.; Wangenheim, K.H. von

1985-01-01

In several systems a paradoxical reduction of radiation damage with increasing dose, termed reversion, has been observed. In the fern Osmunda regalis the percentage of cells which does not die but stays alive, although reproductively sterile, increases with dose. The assumed mechanism of this effect is a continuation of cytoplasmic growth during radiation-induced mitotic delay which induces terminal differentiation (early differentiation) thus preventing mitosis and the expression of chromosomal injury. Suppression of cytoplasmic growth after irradiation should abrogate reversion. This was tested using anoxia. Reversion was suppressed by storage of the sporelings in nitrogen for 8 h or more after X-rays, but was not suppressed by storage in 0.27 μM oxygen nor by a 60-min exposure to air after irradiation and before storage in nitrogen. Anoxia before irradiation in air had no effect.

Does long term sport rock climbing training affect on echocardiography and heart rate variability in sedentary adults? A randomized, and controlled study.

Directory of Open Access Journals (Sweden)

Aras Dicle

2016-03-01

Full Text Available ABSTRACT: Regular physical activity can cause some long term effects on human body. The purpose of this research was to examine the effect of sport rock climbing (SRC training at 70 % HRmax level on echocardiography (ECHO and heart rate variability (HRV for one hour a day and three days a week in an eight-week period. A total of 19 adults participated in this study voluntarily. The subjects were randomly divided into two groups as experimental (EG and control (CG. While the EG went and did climbing training by using the top-rope method for 60 minutes a day, three days a week for 8 weeks and didn’t join any other physical activity programs, CG didn’t train and take part in any physical activity during the course of the study. Same measurements were repeated at the end of eight weeks. According to the findings, no significant change was observed in any of the ECHO and HRV parameters. However, an improvement was seen in some HRV parameters [average heart rate (HRave, standard deviation of all NN intervals (SDNN, standard deviation of the averages of NN intervals in all five-minute segments of the entire recording (SDANN, percent of difference between adjacent NN intervals that are greater than 50 ms (PNN50, square root of the mean of the sum of the squares of differences between adjacent NN interval (RMSSD] in EG. An exercise program based on SRC should be made more than eight weeks in order to have statistically significant changes with the purpose of observing an improvement in heart structure and functions. Keywords: Echocardiography, heart rate variability, sport rock climbing

LA PALABRA DIBUJADA. ANTONIO FERNÁNDEZ-ALBA, PRIMER Y ÚLTIMO MAESTRO / The drawn word. Antonio Fernández-Alba, first and last master

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Juan Luis Trillo de Leyva

2015-05-01

Full Text Available Távora y Fernández-Alba son figuras de referencia ineludible para quienes quieran hoy investigar el origen contemporáneo de la arquitectura peninsular y, sobre todo, de sus escuelas. Alba fue siempre una guía para los que abordamos una enseñanza alejados del aura que acompañaba a los grandes arquitectos madrileños y barceloneses. Su experimentación didáctica alteró la trayectoria de las escuelas de arquitectura españolas. Introdujo la cultura contemporánea en la universidad como si se tratara de una segunda naturaleza, de un nuevo estrato territorial de los proyectos, manteniendo al hombre como objeto central y destinatario de todo proceso proyectual. En época de virtualidad y representación automatizada, nada más adecuado que la revisión de los dibujos del maestro Fernández-Alba. Dibujos que requieren ser proyectados, pensados, antes que ejecutados, “proyectos de proyectos”, una especie de tautología que rige la mente del poeta en su continua reducción, compresión o destilación, gota a gota, del mundo real, del universo y la palabra.