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Journal articles on the topic 'Flipper morphology'
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1
Muscutt, Luke E., Gareth Dyke, Gabriel D. Weymouth, Darren Naish, Colin Palmer, and Bharathram Ganapathisubramani. "The four-flipper swimming method of plesiosaurs enabled efficient and effective locomotion." Proceedings of the Royal Society B: Biological Sciences 284, no. 1861 (August 30, 2017): 20170951. http://dx.doi.org/10.1098/rspb.2017.0951.
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The extinct ocean-going plesiosaurs were unique within vertebrates because they used two flipper pairs identical in morphology for propulsion. Although fossils of these Mesozoic marine reptiles have been known for more than two centuries, the function and dynamics of their tandem-flipper propulsion system has always been unclear and controversial. We address this question quantitatively for the first time in this study, reporting a series of precisely controlled water tank experiments that use reconstructed plesiosaur flippers scaled from well-preserved fossils. Our aim was to determine which limb movements would have resulted in the most efficient and effective propulsion. We show that plesiosaur hind flippers generated up to 60% more thrust and 40% higher efficiency when operating in harmony with their forward counterparts, when compared with operating alone, and the spacing and relative motion between the flippers was critical in governing these increases. The results of our analyses show that this phenomenon was probably present across the whole range of plesiosaur flipper motion and resolves the centuries-old debate about the propulsion style of these marine reptiles, as well as indicating why they retained two pairs of flippers for more than 100 million years.
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Fish, F. E., S. Innes, and K. Ronald. "Kinematics and estimated thrust production of swimming harp and ringed seals." Journal of Experimental Biology 137, no. 1 (July 1, 1988): 157–73. http://dx.doi.org/10.1242/jeb.137.1.157.
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The propulsive motions of swimming harp seals (Phoca groenlandica Erxleben) and ringed seals (Phoca hispida Schreber) were studied by filming individuals in a flume. The seals swam at velocities ranging from 0.6 to 1.42 m s-1. Locomotion was accomplished with alternate lateral sweeps of the hind flippers generated by lateral flexions of the axial body in conjunction with flexion of the flippers. The frequency of the propulsive cycle increased linearly with the swimming velocity, and the maximum angle of attack of the flipper decreased, but the amplitude remained constant. The kinematics and morphology of this hind flipper motion indicated that phocid seals do not swim in the carangiform mode as categorized by Lighthill (1969), but in a distinct mode that mimics swimming by thunniform propulsors. The hind flippers acted as hydrofoils, and the efficiency, thrust power and coefficient of thrust were calculated from unsteady wing theory. The propulsive efficiency was high at approximately 0.85. The thrust power increased curvilinearly with velocity. The drag coefficient ranged from 0.012 to 0.028 and was found to be 2.8-7.0 times higher than the theoretical minimum. The drag coefficient was high compared with that of phocid seals examined during gliding or towing experiments, indicating an increased drag encumbered by actively swimming seals. It was determined that phocid seals are capable of generating sufficient power for swimming with turbulent boundary layer conditions.
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Stor, Thaís, Ginger A. Rebstock, Pablo García Borboroglu, and P. Dee Boersma. "Lateralization (handedness) in Magellanic penguins." PeerJ 7 (May 20, 2019): e6936. http://dx.doi.org/10.7717/peerj.6936.
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Lateralization, or asymmetry in form and/or function, is found in many animal species. Brain lateralization is considered adaptive for an individual, and often results in “handedness,” “footedness,” or a side preference, manifest in behavior and morphology. We tested for lateralization in several behaviors in a wild population of Magellanic penguins Spheniscus magellanicus breeding at Punta Tombo, Argentina. We found no preferred foot in the population (each penguin observed once) in stepping up onto an obstacle: 53% stepped up with the right foot, 47% with the left foot (n = 300, binomial test p = 0.27). We found mixed evidence for a dominant foot when a penguin extended a foot for thermoregulation, possibly depending on the ambient temperature (each penguin observed once). Penguins extended the right foot twice as often as the left foot (n = 121, p < 0.0005) in 2 years when we concentrated our effort during the heat of the day. In a third year when we observed penguins early and late in the day, there was no preference (n = 232, p = 0.59). Penguins use their flippers for swimming, including searching for and chasing prey. We found morphological evidence of a dominant flipper in individual adults: 60.5% of sternum keels curved one direction or the other (n = 76 sterna from carcasses), and 11% of penguins had more feather wear on one flipper than the other (n = 1217). Right-flippered and left-flippered penguins were equally likely in both samples (keels: p = 0.88, feather wear: p = 0.26), indicating individual but not population lateralization. In fights, aggressive penguins used their left eyes preferentially, consistent with the right side of the brain controlling aggression. Penguins that recently fought (each penguin observed once) were twice as likely to have blood only on the right side of the face (69%) as only on the left side (31%, n = 175, p < 0.001). The proportion of penguins with blood only on the right side increased with the amount of blood. In most fights, the more aggressive penguin used its left eye and attacked the other penguin’s right side. Lateralization depended on the behavior tested and, in thermoregulation, likely on the temperature. We found no lateralization or mixed results in the population of Magellanic penguins in three individual behaviors, stepping up, swimming, and thermoregulation. We found lateralization in the population in the social behavior fighting.
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Fish, Frank E., Paul W. Weber, Mark M. Murray, and Laurens E. Howle. "Marine Applications of the Biomimetic Humpback Whale Flipper." Marine Technology Society Journal 45, no. 4 (July 1, 2011): 198–207. http://dx.doi.org/10.4031/mtsj.45.4.1.
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AbstractThe biomimetic approach seeks technological advancement through a transfer of technology from natural technologies to engineered systems. The morphology of the wing-like flipper of the humpback whale has potential for marine applications. As opposed to the straight leading edge of conventional hydrofoils, the humpback whale flipper has a number of sinusoid-like rounded bumps, called tubercles, which are arranged periodically along the leading edge. The presence of the tubercles modifies the water flow over the wing-like surface, creating regions of vortex generation between the tubercles. These vortices interact with the flow over the tubercle and accelerate that flow, helping to maintain a partially attached boundary layer. This hydrodynamic effect can delay stall to higher angles of attack, increases lift, and reduces drag compared to the post-stall condition of conventional wings. As the humpback whale functions in the marine environment in a Reynolds regime similar to some engineered marine systems, the use of tubercles has the potential to enhance the performance of wing-like structures. Specific applications of the tubercles for marine technology include sailboat masts, fans, propellers, turbines, and control surfaces, such as rudders, dive planes, stabilizers, spoilers, and keels.
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García-Grajales, J., J. F. Meraz-Hernando, J. L. Arcos García, and E. Ramírez-Fuentes. "Influence of nest temperature on morphology of Leatherback Turtle (Dermochelys coriacea) hatchlings incubated in hatcheries in Oaxaca, Mexico." Canadian Journal of Zoology 99, no. 5 (May 2021): 369–79. http://dx.doi.org/10.1139/cjz-2020-0083.
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The influence of nest incubation temperatures on carapace shape and morphological traits of Leatherback Turtle (Dermochelys coriacea (Vandelli, 1761)) hatchlings incubated in two hatcheries in Oaxaca, Mexico, was evaluated. This study was carried out from October 2016 through May 2017. On each beach, there are community groups consisting of volunteers not affiliated with universities who protect and relocate the nests to increase hatching success. In each translocated nest, a data logger was placed in the centre of the egg mass. Hatchlings were collected as they emerged from each nest. The carapaces of the hatchlings were photographed and subjected to geometric morphometric analysis; also, hatchlings were weighed and their bodies measured. The mean temperature of 12 nests in each hatchery was recorded, with no significant differences between hatcheries. The principal component analysis revealed an overlapping of the carapace shape under different temperature durations. Temperature had a significant influence on hatchling morphology. Higher mean incubation temperatures produced hatchlings with low mass, smaller appendages, narrower carapace widths, and shorter flipper lengths. Lower mean incubation temperatures produced hatchlings with greater mass, wider appendage widths, wider carapace widths, and longer flipper lengths. Results indicate that the Leatherback hatchlings incubated in hatcheries demonstrate morphology that varies in relation to nest incubation temperature in a similar way to hatchlings produced in natural environments.
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Amano, Masao, and Nobuyuki Miyazaki. "External morphology of Dall's porpoise (Phocoenoides dalli): growth and sexual dimorphism." Canadian Journal of Zoology 71, no. 6 (June 1, 1993): 1124–30. http://dx.doi.org/10.1139/z93-153.
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We studied development and sexual dimorphism in external measurements of Dall's porpoises (Phocoenoides dalli) from the northwestern North Pacific. Relative rates of increase in the measurements of the head and flipper decrease postnatally, while those of the flukes, dorsal fin, and girths in the posterior part of the body do not. Growth patterns of the flukes and increase in girth at the anus are different from those in other small odontocetes. This is considered to be related to the fast swimming and presumed deep diving behavior of Dall's porpoise. Growth rates of appendages decrease with time after birth, as in other cetaceans. Secondary sexual features of males appear in the dorsal fin, flukes, and girth at the anus; the flukes show more distinct sexual dimorphism than the dorsal fin.
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Dewaele, Leonard, Eli Amson, Olivier Lambert, and Stephen Louwye. "Reappraisal of the extinct seal “Phoca”vitulinoidesfrom the Neogene of the North Sea Basin, with bearing on its geological age, phylogenetic affinities, and locomotion." PeerJ 5 (May 16, 2017): e3316. http://dx.doi.org/10.7717/peerj.3316.
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BackgroundDiscovered on the southern margin of the North Sea Basin, “Phoca”vitulinoidesrepresents one of the best-known extinct species of Phocidae. However, little attention has been given to the species ever since its original 19th century description. Newly discovered material, including the most complete specimen of fossil Phocidae from the North Sea Basin, prompted the redescription of the species. Also, the type material of “Phoca”vitulinoidesis lost.Methods“Phoca”vitulinoidesis redescribed. Its phylogenetic position among Phocinae is assessed through phylogenetic analysis. Dinoflagellate cyst biostratigraphy is used to determine and reassess the geological age of the species. Myological descriptions of extant taxa are used to infer muscle attachments, and basic comparative anatomy of the gross morphology and biomechanics are applied to reconstruct locomotion.ResultsDetailed redescription of “Phoca”vitulinoidesindicates relatively little affinities with the genusPhoca, but rather asks for the establishment of a new genus:Nanophocagen. nov. Hence, “Phoca”vitulinoidesis recombined intoNanophoca vitulinoides. This reassignment is confirmed by the phylogenetic analysis, grouping the genusNanophocaand other extinct phocine taxa as stem phocines. Biostratigraphy and lithostratigraphy expand the known stratigraphic range ofN. vitulinoidesfrom the late Langhian to the late Serravallian. The osteological anatomy ofN. vitulinoidesindicates a relatively strong development of muscles used for fore flipper propulsion and increased flexibility for the hind flipper.DiscussionThe extended stratigraphic range ofN. vitulinoidesinto the middle Miocene confirms relatively early diversification of Phocinae in the North Atlantic. Morphological features on the fore- and hindlimb of the species point toward an increased use of the fore flipper and greater flexibility of the hind flipper as compared to extant Phocinae, clearly indicating less derived locomotor strategies in this Miocene phocine species. Estimations of the overall body size indicate thatN. vitulinoidesis much smaller thanPusa, the smallest extant genus of Phocinae (and Phocidae), and than most extinct phocines.
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Mickelson, L. E., and J. R. Downie. "Influence of incubation temperature on morphology and locomotion performance of Leatherback (Dermochelys coriacea) hatchlings." Canadian Journal of Zoology 88, no. 4 (April 2010): 359–68. http://dx.doi.org/10.1139/z10-007.
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The journey of Leatherback ( Dermochelys coriacea (Vandelli, 1761)) hatchlings from nest to the sea is a vulnerable life-history stage. Studies have shown that nest incubation temperatures influence hatchling morphology and locomotor performance, which may affect hatchling fitness. We obtained incubation temperature profiles from 16 Leatherback nests in Tobago, West Indies, during the 2008 nesting season (March–June). There was significant variation among mean nest incubation temperatures, which had a significant influence on hatchling morphology. Using principal components analysis, we determined the morphological traits that explained the most variation among hatchlings, which allowed investigation of the relationship between hatchling morphology and terrestrial locomotion speed. Hatchlings with a narrower carapace width and longer flipper reach (produced at lower incubation temperatures) had significantly faster terrestrial speed and total run time than those with opposite characteristics (produced at higher incubation temperatures). Our results demonstrate that lower incubation temperatures produce hatchlings with traits that are significantly advantageous to terrestrial locomotion. These findings suggest that nest incubation temperature is important in determining hatchling fitness, as nest incubation temperature significantly influences hatchling morphology and locomotor capabilities. This study supplements related findings in Green Turtles ( Chelonia mydas (L., 1758)), but also illustrates some unique features in Leatherbacks.
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Senter, Phil, and Vernetta B. Snow. "Solution to a 300-year-old zoological mystery: the case of Thomas Bartholin's merman." Archives of Natural History 40, no. 2 (October 2013): 257–62. http://dx.doi.org/10.3366/anh.2013.0172.
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In 1654 Dutch anatomist Thomas Bartholin published an illustration of a skeletal forelimb and a rib from an animal that had been caught off the coast of Brazil. Bartholin identified the specimen as a merman. Subsequent authors have hypothesized that it was a human with sirenomelia (fused legs). However, it is now acknowledged that mer-people are mythical and the drawing of the specimen does not match expected morphology for a human with sirenomelia. Until now, therefore, the correct identity of the specimen has remained unknown. Bartholin gave details on the specimen's size and added that before it was skeletonized the fingers were joined by a common membrane. We therefore compared Bartholin's illustration with the forelimb skeletons of west Atlantic marine animals of appropriate size in which the fingers are embedded in a flipper. The morphology of the specimen matches that of a manatee (Trichechus sp.) and is significantly different from that of the Caribbean monk seal (Monachus tropicalis) and from those of whales (Cetacea). The specimen was therefore a manatee, and a three-century-old zoological mystery is solved.
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Kumar, Vivek V., and Dilip A. Shah. "Application of Tubercles in Wind Turbine Blades: A Review." Applied Mechanics and Materials 867 (July 2017): 254–60. http://dx.doi.org/10.4028/www.scientific.net/amm.867.254.
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Due to the rapid depletion of conventional energy resources like fossil fuels and their harmful effects on the environment, there is an urgent need to seek alternative and sustainable energy sources. Wind energy is considered as one of the efficient source of energy which can be converted to useful form of energy like electrical energy. Though the field of wind engineering has developed in the recent era there is still scope for improvement in the effective utilization of energy. Energy efficiency in wind turbine is largely determined by the aerodynamics of the turbine blades and the characteristics of the turbulent fluid flow. The objective of this paper is to have a review on the improvement of Horizontal Axis Wind Turbine (HAWT) blade design by incorporating biomimetics into blades. Biomimetics is the field of science in which we adapt designs from nature to solve modern problems. The morphology of the wing-like flipper of the humpback whale (Megaptera novaeangliae) has potential for aerodynamic applications. Instead of straight leading edges like that of conventional hydrofoils, the humpback whale flipper has a number of sinusoidal rounded bumps, called tubercles arranged periodically along the leading edge. The presence of tubercles modifies the flow over the blade surface, creating vortices between the tubercles. These vortices interact with the flow over the tubercle and accelerate that flow, helping to maintain a partially attached boundary layer. This aerodynamic effect can delay stall to higher angles of attack, increase lift and reduce drag compared to the post-stall condition of conventional airfoils. The modified airfoil is characterized by a superior lift/drag ratio (L/D ratio) due to greater boundary layer attachment from vortices energizing the boundary layer.
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Young, Vanessa K. Hilliard, and Richard W. Blob. "Limb bone loading in swimming turtles: changes in loading facilitate transitions from tubular to flipper-shaped limbs during aquatic invasions." Biology Letters 11, no. 6 (June 2015): 20150110. http://dx.doi.org/10.1098/rsbl.2015.0110.
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Members of several terrestrial vertebrate lineages have returned to nearly exclusive use of aquatic habitats. These transitions were often accompanied by changes in skeletal morphology, such as flattening of limb bone shafts. Such morphological changes might be correlated with the exposure of limb bones to altered loading. Though the environmental forces acting on the skeleton differ substantially between water and land, no empirical data exist to quantify the impact of such differences on the skeleton, either in terms of load magnitude or regime. To test how locomotor loads change between water and land, we compared in vivo strains from femora of turtles ( Trachemys scripta ) during swimming and terrestrial walking. As expected, strain magnitudes were much lower (by 67.9%) during swimming than during walking. However, the loading regime of the femur also changed between environments: torsional strains are high during walking, but torsion is largely eliminated during swimming. Changes in loading regime between environments may have enabled evolutionary shifts to hydrodynamically advantageous flattened limb bones in highly aquatic species. Although circular cross sections are optimal for resisting torsional loads, the removal of torsion would reduce the advantage of tubular shapes, facilitating the evolution of flattened limbs.
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Bonvicino, Cibele Rodrigues, Maria Carolina Viana, Edivaldo H. C. de Oliveira, Renata Emin, José De Sousa e. Silva Junior, Maura Elisabeth Moraes de Sousa, and Salvatore Siciliano. "Distribution of South American manatees, Trichechus manatus Linnaeus, 1758 and T. inunguis (Natterer, 1883) (Sirenia: Trichechidae)." Boletim do Museu Paraense Emílio Goeldi - Ciências Naturais 15, no. 3 (December 21, 2020): 573–99. http://dx.doi.org/10.46357/bcnaturais.v15i3.246.
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South America is unique as it is home of two species of manatees: the West Indian manatee, Trichechus manatus, and the Amazonian manatee, T. inunguis. These species are easily identified by the belly skin coloration, the first is entirely gray whereas T. inunguis has a white mark pattern in the belly, and presence of nails in T. manatus, absent in T. inunguis. The morphology and the range of Trichechus species have been clearly established. However, we show that the belly skin coloration and the presence of nails on the pectoral flipper may be polymorphic. These findings prompted us to check all available information about the manatee. In view of lack of accurate data on manatee locations, we produced a gazetteer and a map of Trichechus spp. in South America using records obtained by regular monitoring of aquatic mammal strandings conducted by the Grupo de Estudos de Mamíferos Aquáticos da Amazônia of the Museu Paraense Emílio Goeldi, all available peer-reviewed data, reports, thesis, and newspaper files with photos showing diagnostic characters. These findings showed the need of improving the identification of these species before implementing conservation strategies. Finally, we present a complete report on the extant distribution of these species in South America.
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Evers, Serjoscha W., Paul M. Barrett, and Roger B. J. Benson. "Anatomy ofRhinochelys pulchriceps(Protostegidae) and marine adaptation during the early evolution of chelonioids." PeerJ 7 (May 1, 2019): e6811. http://dx.doi.org/10.7717/peerj.6811.
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Knowledge of the early evolution of sea turtles (Chelonioidea) has been limited by conflicting phylogenetic hypotheses resulting from sparse taxon sampling and a superficial understanding of the morphology of key taxa. This limits our understanding of evolutionary adaptation to marine life in turtles, and in amniotes more broadly. One problematic group are the protostegids, Early–Late Cretaceous marine turtles that have been hypothesised to be either stem-cryptodires, stem-chelonioids, or crown-chelonioids. Different phylogenetic hypotheses for protostegids suggest different answers to key questions, including (1) the number of transitions to marine life in turtles, (2) the age of the chelonioid crown-group, and (3) patterns of skeletal evolution during marine adaptation. We present a detailed anatomical study of one of the earliest protostegids,Rhinochelys pulchricepsfrom the early Late Cretaceous of Europe, using high-resolution μCT. We synonymise all previously named European species and document the variation seen among them. A phylogeny of turtles with increased chelonioid taxon sampling and revised postcranial characters is provided, recovering protostegids as stem-chelonioids. Our results imply a mid Early Cretaceous origin of total-group chelonioids and an early Late Cretaceous age for crown-chelonioids, which may inform molecular clock analyses in future. Specialisations of the chelonioid flipper evolved in a stepwise-fashion, with innovations clustered into pulses at the origin of total-group chelonioids, and subsequently among dermochelyids, crown-cheloniids, and gigantic protostegids from the Late Cretaceous.
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Ferrada, Enrique E., Bernardo A. Latorre, Juan P. Zoffoli, and Antonio Castillo. "Identification and Characterization of Botrytis Blossom Blight of Japanese Plums Caused by Botrytis cinerea and B. prunorum sp. nov. in Chile." Phytopathology® 106, no. 2 (February 2016): 155–65. http://dx.doi.org/10.1094/phyto-06-15-0143-r.
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Blossom blight is a destructive disease of plums (Prunus salicina) when humid and temperate weather conditions occur in Chile. Disease incidence ranging from 4 to 53% has been observed. Symptoms include light brown petal necrosis, starting as light brown mottles or V-shaped necrosis at the margins of the petals, progressing to the stamen and pistils. In this study, the etiology of blossom blight of plums was determined. High- and low-sporulating isolates of Botrytis were obtained consistently from blighted blossoms and apparently healthy flowers of plums. Based on colony morphology, conidial production and molecular phylogenetic analysis, these high- and low-sporulating isolates were identified as B. cinerea and B. prunorum sp. nov., respectively. Phylogenetic analysis of the genes glyceraldehyde 3-phosphate dehydrogenase (G3PDH), heat-shock protein 60 (HSP60), and DNA-dependent RNA polymerase subunit II (RPB2) grouped B. prunorum isolates in a single cluster, distantly from B. cinerea and other Botrytis species. The phylogenetic analysis of necrosis and ethylene-inducing protein (NEP1 and NEP2) genes corroborated these results. Analysis of the internal transcribed spacer region and large-subunit (26S) ribosomal DNA and detection of Boty and Flipper transposable elements, were not useful to differentiate between these Botrytis species. Both species were pathogenic on plum flowers and the fruit of plums, apples, and kiwifruits. However, B. prunorum was less virulent than B. cinerea. These pathogens were re-isolated from inoculated and diseased tissues; thus, Koch’s postulates were fulfilled, confirming its role in blossom blight of plums. B. cinerea was predominant, suggesting that B. prunorum may play a secondary role in the epidemiology of blossom blight in plums in Chile. This study clearly demonstrated that the etiology of blossom blight of plums is caused by B. cinerea and B. prunorum, which constitute a species complex living in sympatry on plums and possibly on other stone fruit trees.
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ROY, RATNADEEP, and PURUSATTAM RAY. "RESPONSE OF RANDOM FIELD ISING MODEL DRIVEN BY AN EXTERNAL FIELD." International Journal of Modern Physics B 17, no. 29 (November 20, 2003): 5613–22. http://dx.doi.org/10.1142/s0217979203023161.
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We study the dynamics of spin flipping at first order transitions in zero temperature two-dimensional random-field Ising model driven by an external field. We find a critical value of the disorder strength at which a discontinuous sharp jump in magnetization first occurs. We discuss growth morphology of the flipped-spin domains at and away from criticality.
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Martin, Gabriel M., and María Amelia Chemisquy. "Dental anomalies in Caluromys (Marsupialia, Didelphimorphia, Didelphidae, Caluromyinae) and a reassessment of malformations in New World marsupials (Didelphimorphia, Microbiotheria and Paucituberculata)." Mammalia 82, no. 5 (September 25, 2018): 500–508. http://dx.doi.org/10.1515/mammalia-2017-0039.
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Abstract Dental anomalies have been documented in almost all mammalian orders, and include supernumerary or missing teeth, teeth with aberrant occlusal surfaces and/or roots and teeth in unusual positions. Our objectives were the description and categorization of dental anomalies in all species of the genus Caluromys. We studied 462 crania, recorded and classified dental anomalies in four categories: variations in occlusal/root morphology; teeth in unusual positions; supernumerary/missing teeth; presence of unshed deciduous premolars. We found anomalies in all species, with a percentage ranging from 11% to 6.3%. Caluromys derbianus produced anomalous M4/m4 and flipped crowns, the other two species produced higher numbers of missing teeth. We infer that flipped crowns might have consequences in mastication, while other anomalies seem to be less functionally important, especially those at the end of the toothrow. Comparisons with other New World marsupials show caluromyines have more anomalies in M4/m4 shape (similar to microbiotherids) and flipped crowns, while didelphids have more supernumerary teeth, and caenolestids have more missing teeth.
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Kazár, E. "A new kentriodontid (Cetacea: Delphinoidea) from the Middle Miocene of Hungary." Fossil Record 8, no. 1 (January 1, 2005): 53–73. http://dx.doi.org/10.1002/mmng.200410004.
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Abstract. Mediocris commenticius n. gen., n. sp. is herein described as a kentriodontid dolphin from the Sarmatian (late Middle Miocene) of south Hungary, territory of the ancient Central Paratethys Sea. The type specimen is an incomplete skeleton including a distorted skull and mandibles with teeth, ear bones, elements of both flippers, and numerous vertebrae. Mediocris commenticius has a nasal bone morphology that differs from all delphinoid taxa, but is most similar to members of the Pithanodelphininae Barnes, 1985. The nasals are triangular, not inflated, have a faint anterolateral notch, and diverge posteriorly. On the basis of the nasal bone morphology, the new species shows affinities to Pithanodelphis, and is less derived than Atocetus and Sarmatodelphis. Due to the incompleteness of the cranial vertex of the type and only known skull, however, the species is only tentatively referred to the subfamily Pithanodelphininae. Mediocris commenticius n. gen., n. sp. wird als Kentriodontide aus dem Sarmatium (spätes Mittelmiozän) von Südungarn beschrieben, aus dem Gebiet des ehemaligen zentral-paratethyschen Meeres. Der Holotypus ist ein unvollständiges Skelett; erhalten sind der zusammengepresste Schädel, Unterkiefer mit Zähnen, Gehörknochen, Knochenelemente beider Brustflossen sowie zahlreiche Wirbel. Die Morphologie der Nasale der neuen Art unterscheidet sich von allen beschriebenen Taxa der Kentriodontidae, weist aber auf Verwandtschaft mit den Pithanodelphinen hin. Die Nasalia sind dreieckig, nicht extrem vergrößert, sie haben eine schwach ausgebildete anterolaterale Kerbe und sie divergieren in caudaler Richtung. Anhand der Morphologie der Nasale steht M. commenticius der Art Pithanodelphis cornutus nahe und ist weniger stark spezialisiert als Atocetus und Sarmatodelphis. Wegen der unvollständigen Erhaltung des cranialen Vertex ist Mediocris commenticius allerdings nur mit Vorbehalt in die Unterfamilie Pithanodelphininae einzuordnen. doi:10.1002/mmng.200410004
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GAROFALO, L., A. ZACCARONI, D. SCARAVELLI, G. INSACCO, M. P. ZANGRILLI, A. NOVELLETTO, and R. LORENZINI. "Morphology vs Genetics: the hybrid origin of a sea turtle disproved by DNA." Mediterranean Marine Science 13, no. 2 (September 7, 2012): 239. http://dx.doi.org/10.12681/mms.303.
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A putative hybrid sea turtle juvenile was evaluated with discriminant DNA markers. When compared with standard values for sea turtles, the general morphological features assigned the specimen to Caretta caretta, while the shape and coloration of the head and the beak profile fell within the Eretmochelys imbricata range; the front flippers were instead like those of a Chelonia mydas. Moreover, prefrontal scale number was outside the putative parental species’ ranges. The mitochondrial D-loop sequence was from C. caretta, and matched haplotype CC-A2.1, the most common in the Mediterranean. Sequence profiles at three nuclear loci withspecies-specific substitutions (Cmos, BDNF and R35) revealed only C. caretta variants, thus excluding that the individual wasan F1 hybrid. This study highlights the importance of integrating different methodological approaches to understand reproductive animal biology and to set the boundaries for specific morphological traits. In particular, we propose the genetic analysis of a new combination of mitochondrial and nuclear markers as a standard procedure which can be adopted in the identification of sea turtlehybrids.
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Ruhr, Ilan M., Kayleigh A. R. Rose, William I. Sellers, Dane A. Crossley, and Jonathan R. Codd. "Turning turtle: scaling relationships and self-righting ability in Chelydra serpentina." Proceedings of the Royal Society B: Biological Sciences 288, no. 1946 (March 3, 2021): 20210213. http://dx.doi.org/10.1098/rspb.2021.0213.
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Testudines are susceptible to inversion and self-righting using their necks, limbs or both, to generate enough mechanical force to flip over. We investigated how shell morphology, neck length and self-righting biomechanics scale with body mass during ontogeny in Chelydra serpentina , which uses neck-powered self-righting. We found that younger turtles flipped over twice as fast as older individuals. A simple geometric model predicted the relationships of shell shape and self-righting time with body mass. Conversely, neck force, power output and kinetic energy increase with body mass at rates greater than predicted. These findings were correlated with relatively longer necks in younger turtles than would be predicted by geometric similarity. Therefore, younger turtles self-right with lower biomechanical costs than predicted by simple scaling theory. Considering younger turtles are more prone to inverting and their shells offer less protection, faster and less costly self-righting would be advantageous in overcoming the detriments of inversion.
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Resel, Roland, Andrew O. F. Jones, Guillaume Schweicher, Roland Fischer, Nicola Demitri, and Yves Henri Geerts. "Polymorphism of terthiophene with surface confinement." IUCrJ 5, no. 3 (March 29, 2018): 304–8. http://dx.doi.org/10.1107/s2052252518003949.
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The origin of unknown polymorphic phases within thin films is still not well understood. This work reports on crystals of the molecule terthiophene which were grown by thermal gradient crystallization using glass-plate substrates. The crystalline domains displayed a plate-like morphology with an extended lateral size of about 100 µm, but a thickness of only a few µm. Specular X-ray diffraction patterns confirmed the presence of a new polymorph of terthiophene. Crystal structure solution from a single crystal peeled from the film revealed a structure with an extremely large unit-cell volume containing 42 independent molecules. In contrast to the previously determined crystal structure of terthiophene, a herringbone packing motif was observed where the terminal ends of the molecules are arranged within one plane (i.e. the molecular packing conforms to the flat substrate surface). This type of molecular packing is obtained by 180° flipped molecules combined with partially random (disordered) occupation. A densely packed interface between terthiophene crystallites and the substrate surface is obtained, this confirms that the new packing motif has adapted to the flat substrate surface.
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Taheri, Arash. "HYDRODYNAMIC ANALYSIS OF BIONIC CHIMERICAL WING PLANFORMS INSPIRED BY MANTA RAY EIDONOMY." Indonesian Journal of Engineering and Science 2, no. 3 (September 8, 2021): 011–29. http://dx.doi.org/10.51630/ijes.v2i3.25.
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In this paper, inspired by the external morphology of a manta ray (Mobula alfredi), four chimerical wing planforms are designed to assess its gliding performance. The planforms possess an arbitrary combination of extra hydrodynamic features like tubercles at the leading edge (L.E.) and trailing edge (T.E.) inspired by humpback whale's flippers and flukes, respectively, as longitudinal ridges inspired by whale shark's economy. In addition, another planform is designed to investigate the possible effects of manta ray's injuries (geometric deficiency) generated by predator's attacks or boat strikes on its locomotion (gliding) performance. In this regard, turbulent flow physics involved in the problem is numerically simulated at different angles of attack (AoA). High Reynolds number, 106, corresponding to the swimming of a juvenile manta ray at an average speed equals one m/s. The results show that the manta ray-inspired planform with L.E. undulations exhibits a superior performance at high AoAs than its other counterpart variants. In addition, the results demonstrate that injuries on the manta ray's body can noticeably modify hydrodynamics and, as a result corresponding hydrodynamical forces and moments acting on the swimming animal in the gliding phase.
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Zheng, Sanduo, Lok-To Sham, Frederick A. Rubino, Kelly P. Brock, William P. Robins, John J. Mekalanos, Debora S. Marks, Thomas G. Bernhardt, and Andrew C. Kruse. "Structure and mutagenic analysis of the lipid II flippase MurJ fromEscherichia coli." Proceedings of the National Academy of Sciences 115, no. 26 (June 11, 2018): 6709–14. http://dx.doi.org/10.1073/pnas.1802192115.
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The peptidoglycan cell wall provides an essential protective barrier in almost all bacteria, defining cellular morphology and conferring resistance to osmotic stress and other environmental hazards. The precursor to peptidoglycan, lipid II, is assembled on the inner leaflet of the plasma membrane. However, peptidoglycan polymerization occurs on the outer face of the plasma membrane, and lipid II must be flipped across the membrane by the MurJ protein before its use in peptidoglycan synthesis. Due to its central role in cell wall assembly, MurJ is of fundamental importance in microbial cell biology and is a prime target for novel antibiotic development. However, relatively little is known regarding the mechanisms of MurJ function, and structural data for MurJ are available only from the extremophileThermosipho africanus. Here, we report the crystal structure of substrate-free MurJ from the gram-negative model organismEscherichia coli, revealing an inward-open conformation. Taking advantage of the genetic tractability ofE. coli, we performed high-throughput mutagenesis and next-generation sequencing to assess mutational tolerance at every amino acid in the protein, providing a detailed functional and structural map for the enzyme and identifying sites for inhibitor development. Lastly, through the use of sequence coevolution analysis, we identify functionally important interactions in the outward-open state of the protein, supporting a rocker-switch model for lipid II transport.
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Weber, Paul W., Laurens E. Howle, and Mark M. Murray. "Lift, Drag, and Cavitation Onset On Rudders With Leading-edge Tubercles." Marine Technology and SNAME News 47, no. 01 (January 1, 2010): 27–36. http://dx.doi.org/10.5957/mtsn.2010.47.1.27.
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This paper presents the experimental measurement of lift and drag as well as the determination of the onset of cavitation on rudders with leading-edge protuberances (tubercles) that are operating at low to moderate Reynolds Numbers in water. The leading-edge shape used for the rudders in this study is derived from our earlier work concerning the analysis of the leading-edge morphology found on the pectoral flippers of humpback whales. While humpback whales do not swim at speeds that induce cavitation, engineered control surfaces based on this bio-inspired control surface modification might operate in cavitation conditions. This point motivates our present work to investigate the onset of cavitation on small aspect ratio rudders with tubercles. Our findings are that (i) the presence of leading-edge tubercles accelerates the onset of cavitation, (ii) the tubercles can modify the location of the onset of cavitation, (iii) the tubercle geometry has an influence on the rudder's hydrodynamic performance, (iv) for the lower Reynolds Numbers considered in this paper, the tubercles decrease lift and increase drag for angles of attack between 15 and 22 deg, (v) for angles above 22 deg, rudders with tubercles generate more lift than smooth rudders, and (vi) for the higher Reynolds Numbers investigated, the difference in performance between the smooth and tubercled rudders diminishes, suggesting the existence of a critical Reynolds Number for a given tubercle geometry beyond which tubercles have no significant effect on hydrodynamic performance.
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Liu, Qinlai, Wenping Sun, Changqing Du, Leiying Yang, Na Yuan, Haiqing Cui, Wengang Song, and Li Ge. "Medical Morphology Training Using the Xuexi Tong Platform During the COVID-19 Pandemic: Development and Validation of a Web-Based Teaching Approach." JMIR Medical Informatics 9, no. 3 (March 15, 2021): e24497. http://dx.doi.org/10.2196/24497.
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Background Histology and Embryology and Pathology are two important basic medical morphology courses for studying human histological structures under healthy and pathological conditions, respectively. There is a natural succession between the two courses. At the beginning of 2020, the COVID-19 pandemic suddenly swept the world. During this unusual period, to ensure that medical students would understand and master basic medical knowledge and to lay a solid foundation for future medical bridge courses and professional courses, a web-based medical morphology teaching team, mainly including teachers of courses in Histology and Embryology and Pathology, was established. Objective This study aimed to explore a new teaching mode of Histology and Embryology and Pathology courses during the COVID-19 pandemic and to illustrate its feasibility and acceptability. Methods From March to July 2020, our team selected clinical medicine undergraduate students who started their studies in 2018 and 2019 as recipients of web-based teaching. Meanwhile, nursing undergraduate students who started their studies in 2019 and 2020 were selected for traditional offline teaching as the control group. For the web-based teaching, our team used the Xuexi Tong platform as the major platform to realize a new “seven-in-one” teaching method (ie, videos, materials, chapter tests, interactions, homework, live broadcasts, and case analysis/discussion). This new teaching mode involved diverse web-based teaching methods and contents, including flipped classroom, screen-to-screen experimental teaching, a drawing competition, and a writing activity on the theme of “What I Know About COVID-19.” When the teaching was about to end, a questionnaire was administered to obtain feedback regarding the teaching performance. In the meantime, the final written pathology examination results of the web-based teaching and traditional offline teaching groups were compared to examine the mastery of knowledge of the students. Results Using the Xuexi Tong platform as the major platform to conduct “seven-in-one” teaching is feasible and acceptable. With regard to the teaching performance of this new web-based teaching mode, students demonstrated a high degree of satisfaction, and the questionnaire showed that 71.3% or more of the students in different groups reported a greater degree of satisfaction or being very satisfied. In fact, more students achieved high scores (90-100) in the web-based learning group than in the offline learning control group (P=.02). Especially, the number of students with objective scores >60 in the web-based learning group was greater than that in the offline learning control group (P=.045). Conclusions This study showed that the web-based teaching mode was not inferior to the traditional offline teaching mode for medical morphology courses, proving the feasibility and acceptability of web-based teaching during the COVID-19 pandemic. Our findings lay a solid theoretical foundation for follow-up studies of medical students.
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Feldkamp, S. D. "Swimming in the California sea lion: morphometrics, drag and energetics." Journal of Experimental Biology 131, no. 1 (September 1, 1987): 117–35. http://dx.doi.org/10.1242/jeb.131.1.117.
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During swimming, the California sea lion, Zalophus californianus (Lesson), generates thrust forces solely by means of its pectoral flippers. This study examines the drag, energetic cost and efficiency associated with this method of locomotion. Sea lions are highly streamlined, with a fineness ratio of 5.5 and maximum girth at 40% of body length. This profile leads to reduced drag and swimming power requirements. Films of gliding animals showed the drag coefficient (based on wetted surface area) to be 0.0042 at a Reynolds number of 2.0 X 10(6). This value is comparable to that found for other aquatic vertebrates and suggests that the sea lion's morphology helps to delay turbulent separation and maintain laminar flow over the forward portion of its body. Swimming metabolism was measured in a water flume at velocities up to 1.3 ms-1. Effective swimming speeds up to 2.7 ms-1 were attained by increasing each animal's drag. Oxygen consumption rose exponentially with velocity and for two animals was best described as VO2 = 6.27e0.48U, where VO2 is in mlO2 min-1 kg-1 and U is in ms-1. Minimum cost of transport for these animals was 0.12 ml O2 kg-1 m-1 at a relative speed of 1.4 body lengths s-1. This is 2.5 times that predicted for a fish of similar size. Swimming efficiencies were determined from these results using power output values calculated from the measured drag coefficient and standard hydrodynamic equations. At the highest velocity, aerobic efficiency reached a maximum of 15% while mechanical efficiency of the foreflippers was 80%. The results demonstrate that foreflipper propulsion is a highly efficient and comparatively inexpensive method of locomotion in aquatic mammals.
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Pierce, Stephanie E., Megan Williams, and Roger B. J. Benson. "Virtual reconstruction of the endocranial anatomy of the early Jurassic marine crocodylomorphPelagosaurus typus(Thalattosuchia)." PeerJ 5 (April 25, 2017): e3225. http://dx.doi.org/10.7717/peerj.3225.
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Thalattosuchians were highly specialised aquatic archosaurs of the Jurassic and Early Cretaceous, and represent a peak of aquatic adaptation among crocodylomorphs. Relatively little is known of their endocranial anatomy or its relevance for the evolution of sensory systems, physiology, and other aspects of biology. Nevertheless, such data have significance for two reasons: (1) thalattosuchians represent an important data point regarding adaptation to marine life in tetrapods; and (2) as early-diverging members of the crocodylian stem-lineage, thalattosuchians provide information on the evolutionary assembly of the brain and other endocranial structures in crocodylomorphs. Here we use µCT data to virtually reconstruct the endocranial anatomy ofPelagosaurus typus, an early thalattosuchian with plesiomorphic traits of relevance to the split between the two major subgroups: Teleosauroidea and Metriorhynchoidea. Interpretation of these data in a broad comparative context indicate that several key endocranial features may be unique to thalattosuchians, including: a pyramidal morphology of the semicircular canals, the presence of an elongate endosseous cochlear duct that may indicate enhanced hearing ability, the presence of large, paired canals extending anteriorly from an enlarged pituitary fossa, a relatively straight brain (possibly due to the presence of large, laterally placed orbits), and an enlarged venous sinus projecting dorsally from the endocast that is confluent with the paratympanic sinus system. Notably, we document a large expansion of the nasal cavity anterior to the orbits inPelagosaurusas an osteological correlate of an enlarged salt gland previously only documented in Late Jurassic metriorhynchoids. This is the first anatomical evidence of this structure in early thalattosuchians.Pelagosaurusalso shares the presence of paired olfactory bulbs with metriorhynchoids, and shows an enlarged cerebrum, which may also be present in teleosauroids. Taken together, our findings indicate that physiological and sensory adaptations to marine life occurred early in thalattosuchian evolution, predating the origins of flippers, tail flukes, and hydrodynamic body forms seen later in metriorhynchoids.
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Spierer, Adam N., Jim A. Mossman, Samuel Pattillo Smith, Lorin Crawford, Sohini Ramachandran, and David M. Rand. "Natural variation in the regulation of neurodevelopmental genes modifies flight performance in Drosophila." PLOS Genetics 17, no. 3 (March 18, 2021): e1008887. http://dx.doi.org/10.1371/journal.pgen.1008887.
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The winged insects of the orderDipteraare colloquially named for their most recognizable phenotype: flight. These insects rely on flight for a number of important life history traits, such as dispersal, foraging, and courtship. Despite the importance of flight, relatively little is known about the genetic architecture of flight performance. Accordingly, we sought to uncover the genetic modifiers of flight using a measure of flies’ reaction and response to an abrupt drop in a vertical flight column. We conducted a genome wide association study (GWAS) using 197 of theDrosophilaGenetic Reference Panel (DGRP) lines, and identified a combination of additive and marginal variants, epistatic interactions, whole genes, and enrichment across interaction networks.Egfr, a highly pleiotropic developmental gene, was among the most significant additive variants identified. We functionally validated 13 of the additive candidate genes’ (Adgf-A/Adgf-A2/CG32181,bru1,CadN,flapper(CG11073),CG15236,flippy(CG9766),CREG,Dscam4,form3,fry,Lasp/CG9692,Pde6,Snoo), and introduce a novel approach to whole gene significance screens:PEGASUS_flies. Additionally, we identifiedppk23, an Acid Sensing Ion Channel (ASIC) homolog, as an important hub for epistatic interactions. We propose a model that suggests genetic modifiers of wing and muscle morphology, nervous system development and function, BMP signaling, sexually dimorphic neural wiring, and gene regulation are all important for the observed differences flight performance in a natural population. Additionally, these results represent a snapshot of the genetic modifiers affecting drop-response flight performance inDrosophila, with implications for other insects.
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Soliman, MennaAllah, Mostafa A. Mousa, Mahmood A. Saleh, Mahmoud Elsamanty, and Ahmed G. Radwan. "Modelling and implementation of soft bio-mimetic turtle using echo state network and soft pneumatic actuators." Scientific Reports 11, no. 1 (June 8, 2021). http://dx.doi.org/10.1038/s41598-021-91136-z.
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AbstractAdvances of soft robotics enabled better mimicking of biological creatures and closer realization of animals’ motion in the robotics field. The biological creature’s movement has morphology and flexibility that is problematic deportation to a bio-inspired robot. This paper aims to study the ability to mimic turtle motion using a soft pneumatic actuator (SPA) as a turtle flipper limb. SPA’s behavior is simulated using finite element analysis to design turtle flipper at 22 different geometrical configurations, and the simulations are conducted on a large pressure range (0.11–0.4 Mpa). The simulation results are validated using vision feedback with respect to varying the air pillow orientation angle. Consequently, four SPAs with different inclination angles are selected to build a bio-mimetic turtle, which is tested at two different driving configurations. The nonlinear dynamics of soft actuators, which is challenging to model the motion using traditional modeling techniques affect the turtle’s motion. Conclusively, according to kinematics behavior, the turtle motion path is modeled using the Echo State Network (ESN) method, one of the reservoir computing techniques. The ESN models the turtle path with respect to the actuators’ rotation motion angle with maximum root-mean-square error of $$1.04 \times 10^{-11}$$ 1.04 × 10 - 11 . The turtle is designed to enhance the robot interaction with living creatures by mimicking their limbs’ flexibility and the way of their motion.
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MacCain, William J., Suresh Kannan, Dannah Z. Jameel, Jerry M. Troutman, and Kevin D. Young. "A Defective Undecaprenyl Pyrophosphate Synthase Induces Growth and Morphological Defects That Are Suppressed by Mutations in the Isoprenoid Pathway ofEscherichia coli." Journal of Bacteriology 200, no. 18 (July 9, 2018). http://dx.doi.org/10.1128/jb.00255-18.
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ABSTRACTThe peptidoglycan exoskeleton shapes bacteria and protects them against osmotic forces, making its synthesis the target of many current antibiotics. Peptidoglycan precursors are attached to a lipid carrier and flipped from the cytoplasm into the periplasm to be incorporated into the cell wall. InEscherichia coli, this carrier is undecaprenyl phosphate (Und-P), which is synthesized as a diphosphate by the enzyme undecaprenyl pyrophosphate synthase (UppS).E. coliMG1655 exhibits wild-type morphology at all temperatures, but one of our laboratory strains (CS109) was highly aberrant when grown at 42°C. This strain contained mutations affecting the Und-P synthetic pathway genesuppS,ispH, andidi. Normal morphology was restored by overexpressinguppSor by replacing the mutant (uppS31) with the wild-type allele. Importantly, movinguppS31into MG1655 was lethal even at 30°C, indicating that the altered enzyme was highly deleterious, but growth was restored by adding the CS109 versions ofispHandidi. Purified UppSW31Rwas enzymatically defective at all temperatures, suggesting that it could not supply enough Und-P during rapid growth unless suppressor mutations were present. We conclude that cell wall synthesis is profoundly sensitive to changes in the pool of polyisoprenoids and that isoprenoid homeostasis exerts a particularly strong evolutionary pressure.IMPORTANCEBacterial morphology is determined primarily by the overall structure of the semirigid macromolecule peptidoglycan. Not only does peptidoglycan contribute to cell shape, but it also protects cells against lysis caused by excess osmotic pressure. Because it is critical for bacterial survival, it is no surprise that many antibiotics target peptidoglycan biosynthesis. However, important gaps remain in our understanding about how this process is affected by peptidoglycan precursor availability. Here, we report that a mutation altering the enzyme that synthesizes Und-P prevents cells from growing at high temperatures and that compensatory mutations in enzymes functioning upstream ofuppScan reverse this phenotype. The results highlight the importance of Und-P metabolism for maintaining normal cell wall synthesis and shape.
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Río, Santiago Bernal-del, and Gilberto Osorio-Gómez. "Experimental Comparison of Energy Generation between Conventional and Wavy Leading Edge Blades in HAWT." International Journal of Electrical and Electronic Engineering & Telecommunications, 2020, 441–46. http://dx.doi.org/10.18178/ijeetc.9.6.441-446.
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Horizontal Axis Wind Turbine (HAWT) is one of the most important devices for electricity generation from Wind Energy, and design of new blades has become a fundamental research field to improve the efficiency and to reduce cost of this system. This article presents a preliminary comparison between two micro Wind Turbines (WT), one with standard blades and another one with Wavy Leading Edge (WLE) morphology, inspired by the flippers of the humpback whale, to work at low-speed wind conditions. To perform a correct validation, the authors propose a four steps approach for the design, manufacture and test of a WT. First, the design of the blade, followed by the design of the Wind Turbine (WT). Next step is the manufacture of two functional models, one with WLE and another with standard blades, to make a relative comparison, and, finally, the acquisition of real-time data from these systems for the corresponding analysis in terms of energy generation. Results show that the WLE has an increase of over 20% in energy production in all the tests that were performed, with respect to the standard blade.
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Kim, In Ki, Kook Lee, Jae Hyun Park, Jiwon Baek, and Won Ki Lee. "Classification of pachychoroid disease on ultrawide-field indocyanine green angiography using auto-machine learning platform." British Journal of Ophthalmology, July 3, 2020, bjophthalmol—2020–316108. http://dx.doi.org/10.1136/bjophthalmol-2020-316108.
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AimsAutomatic identification of pachychoroid maybe used as an adjunctive method to confirm the condition and be of help in treatment for macular diseases. This study investigated the feasibility of classifying pachychoroid disease on ultra-widefield indocyanine green angiography (UWF ICGA) images using an automated machine-learning platform.MethodsTwo models were trained with a set including 783 UWF ICGA images of patients with pachychoroid (n=376) and non-pachychoroid (n=349) diseases using the AutoML Vision (Google). Pachychoroid was confirmed using quantitative and qualitative choroidal morphology on multimodal imaging by two retina specialists. Model 1 used the original and Model 2 used images of the left eye horizontally flipped to the orientation of the right eye to increase accuracy by equalising the mirror image of the right eye and left eye. The performances were compared with those of human experts.ResultsIn total, 284, 279 and 220 images of central serous chorioretinopathy, polypoidal choroidal vasculopathy and neovascular age-related maculopathy were included. The precision and recall were 87.84% and 87.84% for Model 1 and 89.19% and 89.19% for Model 2, which were comparable to the results of the retinal specialists (90.91% and 95.24%) and superior to those of ophthalmic residents (68.18% and 92.50%).ConclusionsAuto machine-learning platform can be used in the classification of pachychoroid on UWF ICGA images after careful consideration for pachychoroid definition and limitation of the platform including unstable performance on the medical image.