Journal articles: 'Terrestial worm'

1

Shin, Dong-Chul, Jae-Kil Kim, and Jae-Min Ahn. "Channel estimation scheme of terrestrial DTV transmission employing unique-word based SC-FDE." Journal of Broadcast Engineering 16, no. 2 (March 30, 2011): 207–15. http://dx.doi.org/10.5909/jeb.2011.16.2.207.

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Martinsson, Svante, and Christer Erséus. "Cryptic diversity in the well-studied terrestrial worm Cognettia sphagnetorum (Clitellata: Enchytraeidae)." Pedobiologia 57, no. 1 (January 2014): 27–35. http://dx.doi.org/10.1016/j.pedobi.2013.09.006.

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Ogawa, Shigeru, Mamoru Mizuno, Mayuko Suzuki, Kohtaro Goto, Yuriko Hirose, Akio Matsuda, Takuya Saito, Suguru Oguri, and Kiyoshi Furukawa. "Isolation of a methylated mannose-binding protein from terrestrial worm Enchytraeus japonensis." Glycoconjugate Journal 34, no. 5 (June 2, 2017): 591–601. http://dx.doi.org/10.1007/s10719-017-9778-3.

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de Boer, Tjalf E., Dick Roelofs, Riet Vooijs, Martin Holmstrup, and Mónica J. B. Amorim. "Population-specific transcriptional differences associated with freeze tolerance in a terrestrial worm." Ecology and Evolution 8, no. 7 (March 11, 2018): 3774–86. http://dx.doi.org/10.1002/ece3.3602.

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Butcher, Andrew R. "Children, snails and worms: the Brachylaima cribbi story." Microbiology Australia 37, no. 1 (2016): 30. http://dx.doi.org/10.1071/ma16012.

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Brachylaimids are parasitic trematode fluke worms that have a terrestrial life cycle involving land snails and slugs as the first and/or second intermediate hosts for the cercarial and metacercarial larval stages. A wide range of mammals, birds, reptiles and amphibians are the definitive hosts for the adult worm. Brachylaima spp. have been reported from most continents including Europe, Africa, Asia, North and South America and Australia. There are over 70 described species in the genus with seven species indigenous to Australia. Although Brachylaima spp. are a cosmopolitan terrestrial trematode they have not been recorded to infect humans other than the three Brachylaima cribbi infections reported in two children and an adult from South Australia.

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Chiu, Ming-Chung, Chin-Gi Huang, Wen-Jer Wu, Zhao-Hui Lin, Hsuan-Wien Chen, and Shiuh-Feng Shiao. "A new millipede-parasitizing horsehair worm, Gordius chiashanus sp. nov., at medium altitudes in Taiwan (Nematomorpha, Gordiida)." ZooKeys 941 (June 16, 2020): 25–48. http://dx.doi.org/10.3897/zookeys.941.49100.

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Gordius chiashanussp. nov., a newly described horsehair worm that parasitizes the Spirobolus millipede, is one of the three described horsehair worm species in Taiwan. It is morphologically similar to G. helveticus Schmidt-Rhaesa, 2010 because of the progressively broadening distribution of bristles concentrated on the male tail lobes, but it is distinguishable from G. helveticus because of the stout bristles on the mid-body. In addition, a vertical white stripe on the anterior ventral side and areoles on the inside wall of the cloacal opening are rarely mentioned in other Gordius species. Free-living adults emerged and mated on wet soil under the forest canopy in the winter (late November to early February) at medium altitudes (1100–1700 m). Mucus-like structure covering on the body surface, which creates a rainbow-like reflection, might endow the worm with high tolerance to dehydration. Although Gordius chiashanussp. nov. seems to be more adaptive to the terrestrial environment than other horsehair worm species, cysts putatively identified as belonging to this hairworm species found in the aquatic paratenic host, Ephemera orientalis McLachlan, 1875, suggest the life cycle of Gordius chiashanussp. nov. could involve water and land. The free-living adults emerged from the definitive hosts might reproduce in the terrestrial environment or enter an aquatic habitat by moving or being washed away by heavy rain instead of manipulating the behavior of their terrestrial definitive hosts.

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Stites, David L. "Population and Production Dynamics of an Enchytraeid Worm in a Subtropical Blackwater River." Canadian Journal of Fisheries and Aquatic Sciences 44, no. 8 (August 1, 1987): 1469–74. http://dx.doi.org/10.1139/f87-176.

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Population and production dynamics of Barbidrilus paucisetus Loden and Locy (Oligochaeta: Enchytraeidae) in a sixth-order blackwater river are described. This worm was the dominant member of the meiofauna of the sand habitat, accounting for 50–90% of the total density. Population density varied seasonally, increasing from < 20 000/m2 in the winter to 60–120 000/m2 in the summer. Biomass averaged 145 mg dry mass/m2 with a range of 8–326 mg/m2. Density peaked in the clean coarse sand of the center channel areas and was lower where the sand was finer and where more organic matter was present. Size frequency histograms indicated that there were three recruitment peaks during the sampling year, with mature and new individuals present in all seasons. Annual production (2.12 g dry mass/m2, SE = 0.15 g/m2), was estimated using the size frequency method and a cohort production interval correction of 3. Annual production was low compared with that of terrestrial Enchytraeidae and comparable with that of many aquatic insect species. Annual production/biomass ratio (14.3) was higher than terrestrial Enchytraeidae, due to the comparatively short generation time of this species.

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Lahive, Elma, Alexander Walton, Alice A. Horton, David J. Spurgeon, and Claus Svendsen. "Microplastic particles reduce reproduction in the terrestrial worm Enchytraeus crypticus in a soil exposure." Environmental Pollution 255 (December 2019): 113174. http://dx.doi.org/10.1016/j.envpol.2019.113174.

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Cherrington, Jim, and Jack Black. "Mountain Bike Trail Building, “Dirty” Work, and a New Terrestrial Politics." World Futures 76, no. 1 (December 17, 2019): 39–61. http://dx.doi.org/10.1080/02604027.2019.1698234.

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10

Forbes, Stephen A. "An American Terrestrial Leech." Illinois Natural History Survey Bulletin 3, no. 1-15 (June 11, 2019): 119–22. http://dx.doi.org/10.21900/j.inhs.v3.190.

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Our common land leech was first obtained by me in April, 1876, at Normal, McLean County, Illinois, where it was dug up in a house garden, about a dozen rods from the nearest rivulet. An example sent the following year to Prof. A. E. Verrill, with some remarks on its superficial characters, was by him identified provisionally and with some hesitation as his Semiscolex grandis, originally described* from three aquatic individuals obtained from Lake Huron, Lake Superior, and West River, Connecticut. I have now, however, fifty-six specimens of this leech, all from the earth in Central Illinois, some of them half a mile or more from water, and representing collections made at different times from April, 1876, to June, 1890 ; while, on the other hand, it has not once occurred in the course of a large amount of aquatic work done in the same regions during these fifteen years. It has, moreover, constant characters which clearly distinguish it from Semiscolex qrandis as far as one may judge by a comparison with Verrill's description, and I do not doubt that it is distinct.

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Balbuena, J. A., P. E. Aspholm, K. I. Andersen, and A. Bjørge. "Lung-worms (Nematoda: Pseudaliidae) of harbour porpoises (Phocoena phocoena) in Norwegian waters: patterns of colonization." Parasitology 108, no. 3 (April 1994): 343–49. http://dx.doi.org/10.1017/s0031182000076186.

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SUMMARYWe studied the component community of lung-worms of the harbour porpoise, attempting to establish the relative importance of ecological and evolutionary factors on its development. The lungs of 64 porpoises by-caught in Norwegian waters were examined for helminths. Three pseudaliid species were detected. The porpoises appear to be readily colonized by lung-worms, the structure of the component community of calves being fairly similar to that of the remainder. Prenatal and/or transmammary infections might partly account for these early infections. However, host age was correlated with the number of lung-worm species, suggesting that the lung-worms may have heteroxenous cycles similar to other metastrongyloids. The lung-worm species tended to co-occur more often than expected by chance. This pattern is commonly observed in communities formed by phylogenetic relatives. Mean species richness of lung nematodes differed significantly among mammalian orders. However, species richness of marine species seemed very similar to those of most terrestrial species. This evidence suggests that phylogenetic factors seem more important than ecological ones in determining the number of lung-worm species in mammals.

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Miladinović-Tasić, N., A. Schmidt-Rhaesa, and V. Petrović. "Human encounter with a horsehair worm (Nematomorpha): Is there a reason to worry?" Helminthologia 59, no. 2 (June 1, 2022): 200–203. http://dx.doi.org/10.2478/helm-2022-0020.

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Summary We report here a specimen of the horsehair worm (Gordiida, Nematomorpha) Spinochordodes bacescui (Căpuşe, 1965) found in a patient´s urine. This is the first record of this species from Serbia and the sixth gordiid species known in Serbia. It is discussed that there is no evidence that gordiids are parasites of humans. Instead, gordiids parasitize terrestrial insects, which release their mature gordiid parasite into water and may thereby also use containers in human surroundings. Pseudoparasites, such as Spinochordodes bacescui, do not pose a threat to human health nor are they a serious public health issue.

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Biewener, A. A., and W. R. Corning. "Dynamics of mallard (Anas platyrynchos) gastrocnemius function during swimming versus terrestrial locomotion." Journal of Experimental Biology 204, no. 10 (May 15, 2001): 1745–56. http://dx.doi.org/10.1242/jeb.204.10.1745.

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This study investigates how the contractile function of a muscle may be modulated to accommodate changes in locomotor mode and differences in the physical environment. In vivo recordings of lateral gastrocnemius (LG) activation, force development (measured using tendon buckle transducers) and length change (measured using sonomicrometry) were obtained from mallard ducks (Anas platyrhynchos) as they swam at steady speeds in a water tank and walked or ran on land. LG force recordings were compared with combined lateral and medial gastrocnemius (MG) muscle-tendon force recordings obtained from the contralateral limb, allowing force development by the MG to be estimated relative to that of the LG. Although similar stresses were calculated to act in the LG and MG muscles during terrestrial locomotion (126 and 115 kPa, respectively), stresses were considerably greater in the LG compared with the MG during swimming (62 versus 34 kPa, respectively). During both steady swimming and terrestrial locomotion, the LG developed force while shortening over a considerable range of its length (swimming 23.6 % versus terrestrial 37.4 %). Activation of the muscle occurred near the end of passive lengthening during the recovery stroke, just prior to muscle shortening. As a result, the muscle generated broad positive work loops during both locomotor modes. LG work during swimming (4.8 J kg(−)(1)) averaged 37 % of the work performed during terrestrial locomotion (13.1 J kg(−)(1)), consistent with the twofold greater force and 58 % greater strain of the muscle during walking and running. Because limb cycle frequency was similar for the two locomotor modes (swimming 2.65 versus terrestrial 2.61 Hz), differences in power output (swimming 12.6 W kg(−)(1)versus terrestrial 32.4 W kg(−)(1)) largely reflected difference in work per cycle. Tendon elastic energy savings was a small fraction (<5 %) of the work performed by the muscle, consistent with a fiber-tendon design of these two muscles that favors muscle work to produce limb movement with little tendon strain. These results are consistent with a higher cost of terrestrial locomotion in ducks compared with other, more cursorial birds that may operate their muscles more economically and achieve greater tendon elastic savings.

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Majer, Jonathan D., Nihara R. Gunawardene, Christopher K. Taylor, and Mark S. Harvey. "The terrestrial invertebrate fauna of Barrow Island, Western Australia: A last word." Records of the Western Australian Museum, Supplement 83, no. 1 (2013): 405. http://dx.doi.org/10.18195/issn.0313-122x.83.2013.405-406.

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15

Sanson, Gordon. "Cutting food in terrestrial carnivores and herbivores." Interface Focus 6, no. 3 (June 6, 2016): 20150109. http://dx.doi.org/10.1098/rsfs.2015.0109.

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Insects and mammals cut their food up into small pieces to facilitate ingestion and chemical digestion. Teeth and jaws act as cutting tools, but, unlike engineering tools designed for a specific purpose, must generally cope with substantial variation in food properties and work at many scales. Knowing how teeth and jaws work effectively requires an understanding of the cutting on the edges and the mechanisms that remove cut material. Variability and heterogeneity of diet properties are not well known, and, for example, may be higher and overlap more in the browsing and grazing categories of plant diets. A reinterpretation of tooth function in large mammal browsers and grazers is proposed.

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Sharma, A., and J. K. Ghosh. "SALIENCY BASED SEGMENTATION OF SATELLITE IMAGES." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences II-3/W4 (March 11, 2015): 207–14. http://dx.doi.org/10.5194/isprsannals-ii-3-w4-207-2015.

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Saliency gives the way as humans see any image and saliency based segmentation can be eventually helpful in Psychovisual image interpretation. Keeping this in view few saliency models are used along with segmentation algorithm and only the salient segments from image have been extracted. The work is carried out for terrestrial images as well as for satellite images. The methodology used in this work extracts those segments from segmented image which are having higher or equal saliency value than a threshold value. Salient and non salient regions of image become foreground and background respectively and thus image gets separated. For carrying out this work a dataset of terrestrial images and Worldview 2 satellite images (sample data) are used. Results show that those saliency models which works better for terrestrial images are not good enough for satellite image in terms of foreground and background separation. Foreground and background separation in terrestrial images is based on salient objects visible on the images whereas in satellite images this separation is based on salient area rather than salient objects.

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He, Qiu-Lan, Jun-Lan Xiao, and Wei-Yu Shi. "Responses of Terrestrial Evapotranspiration to Extreme Drought: A Review." Water 14, no. 23 (November 26, 2022): 3847. http://dx.doi.org/10.3390/w14233847.

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Terrestrial evapotranspiration (ET) is crucial to the exchange of global carbon, water, and energy cycles and links the hydrological and ecological processes. The frequency and intensity of extreme droughts are expected to increase due to ongoing climate change, strongly impacting terrestrial ET with implications for ecosystems, societies, and climate systems. However, the response of terrestrial ET to extreme drought and the underlying mechanism of terrestrial ET change during droughts are still unclear. Here, we review previous studies on terrestrial ET’s responses to extreme drought and investigate the control factors of ET change in response to extreme drought under different situations. The response of terrestrial ET to extreme drought is affected by various factors including the duration and intensity of the drought, the original climate conditions, as well as the plant species. Terrestrial ET change during droughts is controlled by complex biological and physical processes that can be divided into four parts including supply, energy, demand, and vegetation activities. The response of terrestrial ET to elevate CO2 may offset the effects of drought because CO2 fertilization tends to increase water use efficiency through stomatal regulation. We found that large uncertainties remain in the terrestrial ET response to drought due to the discrepancies among different ET products and simulations. This work highlights the requirement for accurate estimates of ET changes in ET products and models. This review provides a systematic investigation of the terrestrial ET response to extreme drought and the underlying mechanism of terrestrial ET changes during droughts and will significantly improve the development of water management strategies under climate change.

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Ward, Peter. "Biogeographic Implications of Changing Oxygen Levels through Time." Paleontological Society Papers 11 (October 2005): 45–48. http://dx.doi.org/10.1017/s1089332600001236.

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Changing oxygen values in the past would have changed the potential for gene flow across higher elevations in terrestrial settings. In this brief review I discuss new work showing that intervals of low oxygen (essentially the late Permian through Middle Jurassic) should have caused extreme endemism among terrestrial animals and perhaps plants.

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Kocot-Zalewska, Joanna, and Paweł Domagała. "Terrestrial invertebrate fauna of Polish caves – a summary of 100 years of research." Subterranean Biology 33 (February 13, 2020): 45–69. http://dx.doi.org/10.3897/subtbiol.33.48805.

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The year 2018 is particularly important in the history of zoological research in Poland. A hundred years ago, Kazimierz Demel published the first work concerning the terrestrial cave fauna of caves in the Ojców area. In this paper we present the extent of research on the terrestrial invertebrate fauna of Polish caves in the last 100 years. All accessible research papers that have been published during this period were analysed. Based on published literature, 593 species of terrestrial invertebrate were recorded in Polish caves. Additionally, detailed list of species of individual taxonomic groups was provided.

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Haverd, V., M. R. Raupach, P. R. Briggs, J. G. Canadell, S. J. Davis, R. M. Law, C. P. Meyer, G. P. Peters, C. Pickett-Heaps, and B. Sherman. "The Australian terrestrial carbon budget." Biogeosciences Discussions 9, no. 9 (September 12, 2012): 12259–308. http://dx.doi.org/10.5194/bgd-9-12259-2012.

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Abstract. This paper reports a study of the full carbon (C-CO2) budget of the Australian continent, focussing on 1990–2011 in the context of estimates over two centuries. The work is a contribution to the RECCAP (REgional Carbon Cycle Assessment and Processes) project, as one of numerous regional studies being synthesised in RECCAP. In constructing the budget, we estimate the following component carbon fluxes: Net Primary Production (NPP); Net Ecosystem Production (NEP); fire; Land Use Change (LUC); riverine export; dust export; harvest (wood, crop and livestock) and fossil fuel emissions (both territorial and non-territorial). The mean NEP reveals that climate variability and rising CO2 contributed 12 ± 29 (1σ error on mean) and 68 ± 35 Tg C yr−1 respectively. However these gains were partially offset by fire and LUC (along with other minor fluxes), which caused net losses of 31 ± 5 Tg C yr−1 and 18 ± 7 Tg C yr−1 respectively. The resultant Net Biome Production (NBP) of 31 ± 35 Tg C yr−1 offset fossil fuel emissions (95 ± 6 Tg C yr−1) by 32 ± 36%. The interannual variability (IAV) in the Australian carbon budget exceeds Australia's total carbon emissions by fossil fuel combustion and is dominated by IAV in NEP. Territorial fossil fuel emissions are significantly smaller than the rapidly growing fossil fuel exports: in 2009–2010, Australia exported 2.5 times more carbon in fossil fuels than it emitted by burning fossil fuels.

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Wang, Aihua, Peisen Wang, Xiaqing Miao, Xiangming Li, Neng Ye, and Yun Liu. "A review on non-terrestrial wireless technologies for Smart City Internet of Things." International Journal of Distributed Sensor Networks 16, no. 6 (June 2020): 155014772093682. http://dx.doi.org/10.1177/1550147720936824.

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Smart City Internet of Things will become a fundamental infrastructure to support massive machine-type communications between the widely deployed sensors serving big cities. Since there exists many location constraints for the existing terrestrial Internet of Things, the non-terrestrial Internet of Things sheds light on breaking these limits. Therefore, this article conducts a comprehensive survey on non-terrestrial Internet of Things technologies for Smart City, which is an important complement to terrestrial Internet of Things. We first present the application scenarios of Internet of Things and point out where the existing terrestrial Internet of Things cannot work perfectly. Two non-terrestrial Internet of Things technical proposals are then introduced, namely satellite Internet of Things and unmanned aerial vehicle Internet of Things. However, the focuses of these non-terrestrial Internet of Things are distinct, that is, the major problems of satellite and unmanned aerial vehicle Internet of Things are the high dynamic nature of channel and high maneuverability of unmanned aerial vehicles, respectively. The key technologies for satellite and unmanned aerial vehicle Internet of Things are then reviewed separately. Both physical and non-physical layer technologies are surveyed for satellite Internet of Things, and the route planning is mainly investigated for the unmanned aerial vehicle Internet of Things. Finally, we draw a conclusion and give some potential research directions of non-terrestrial Internet of Things.

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Gortzis, Lefteris G., Homer Papadopoulos, Theo A. Roelofs, Stefan Rakowsky, Dimitris Karnabatidis, Dimitris Siablis, Constantinos Makropoulos, George Nikiforidis, and Georgi Graschew. "Collaborative Work During Interventional Radiological Procedures Based on a Multicast Satellite-Terrestrial Network." IEEE Transactions on Information Technology in Biomedicine 11, no. 5 (September 2007): 597–99. http://dx.doi.org/10.1109/titb.2007.894724.

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23

Minetti, Alberto E. "A model equation for the prediction of mechanical internal work of terrestrial locomotion." Journal of Biomechanics 31, no. 5 (May 1998): 463–68. http://dx.doi.org/10.1016/s0021-9290(98)00038-4.

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24

Martin, Laura J., Bernd Blossey, and Erle Ellis. "Mapping where ecologists work: biases in the global distribution of terrestrial ecological observations." Frontiers in Ecology and the Environment 10, no. 4 (May 2012): 195–201. http://dx.doi.org/10.1890/110154.

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25

Ljungholm, Mikael, and Dan-E. Nilsson. "Modelling the visual world of a velvet worm." PLOS Computational Biology 17, no. 7 (July 28, 2021): e1008808. http://dx.doi.org/10.1371/journal.pcbi.1008808.

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In many animal phyla, eyes are small and provide only low-resolution vision for general orientation in the environment. Because these primitive eyes rarely have a defined image plane, traditional visual-optics principles cannot be applied. To assess the functional capacity of such eyes we have developed modelling principles based on ray tracing in 3D reconstructions of eye morphology, where refraction on the way to the photoreceptors and absorption in the photopigment are calculated incrementally for ray bundles from all angles within the visual field. From the ray tracing, we calculate the complete angular acceptance function of each photoreceptor in the eye, revealing the visual acuity for all parts of the visual field. We then use this information to generate visual filters that can be applied to high resolution images or videos to convert them to accurate representations of the spatial information seen by the animal. The method is here applied to the 0.1 mm eyes of the velvet worm Euperipatoides rowelli (Onychophora). These eyes of these terrestrial invertebrates consist of a curved cornea covering an irregular but optically homogeneous lens directly joining a retina packed with photoreceptive rhabdoms. 3D reconstruction from histological sections revealed an asymmetric eye, where the retina is deeper in the forward-pointing direction. The calculated visual acuity also reveals performance differences across the visual field, with a maximum acuity of about 0.11 cycles/deg in the forward direction despite laterally pointing eyes. The results agree with previous behavioural measurements of visual acuity, and suggest that velvet worm vision is adequate for orientation and positioning within the habitat.

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Bukina. "PECULIARITIES OF THE NATURAL ORIGIN OF TRICHINELLOSIS IN THE CHUKOT PENINSULA TERRITORY." THEORY AND PRACTICE OF PARASITIC DISEASE CONTROL, no. 20 (May 14, 2019): 151–55. http://dx.doi.org/10.31016/978-5-9902340-8-6.2019.20.151-155.

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Trichinellosis is a natural focal nontransmissive zoonotic disease, the causative agent of which is the nematode Trichinella nativa (T2). The collection of biological material was carried out on the territory of the coastal settlements of the Chukot Peninsula. The objects of the presented work were the representatives of the order carnivore (Carnivora) of the following families: canids (Canidae), feline (Felidae), bears (Ursidae), walrus (Odobenidae), seal (Phocidae) and the whale (Сetacea). Larvae detection from the muscle tissue of animals was carried out by standard methods. Infection rates were determined by the extensiveness (EI) and intensity of invasion (II).During the evolution Trichinella have acquired a wide range of hosts with similar trophic relations, and therefore they ensure the long-term functioning of the natural focus. The organism of the animals, which are host species, plays the role of reservoir (the reservation phase). There were the following components of the guest component among the studied host species: 5 species of terrestrials, and 4 species of marine mammals. The animals’ contamination ranged from 60.0% to 100% in terrestrials, and it ranged from 0.9% to 4.3% in marine animals. Successful circulation of Trichinella nativa (dispersion phase, distribution) under the extreme conditions of Arctic region became possible due to several reasons. They are: getting tolerated to low temperatures in the process of evolution, the process of decay and a number of other adaptive properties that allow them to maintain viability and invasive properties in the corpses of terrestrial carnivores and marine mammals during the long winter. The natural focus of trichinellosis on the territory of the Chukot Peninsula is unique and multifaceted in nature, and it is of interest for researchers to learn environmental and general biological laws, taking into account the traditional economic activities of the indigenous population.

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Schmidt-Rhaesa, Andreas, Gerhard Pohle, Julien Gaudette, and Victoria Burdett-Coutts. "Lobster (Homarus americanus), a new host for marine horsehair worms (Nectonema agile, Nematomorpha)." Journal of the Marine Biological Association of the United Kingdom 93, no. 3 (June 14, 2012): 631–33. http://dx.doi.org/10.1017/s0025315412000719.

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Nectonema species are parasites of decapod crustaceans and the only known representatives of the otherwise freshwater/terrestrial taxon Nematomorpha. We report the American lobster, Homarus americanus, as a new host for Nectonema agile, a first record among astacidean decapods. A female, about 590 mm long, was found in the body cavity of one female lobster specimen. We assume lobster to be a very rare host for Nectonema.

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Weil, J. A., and D. F. Howarth. "Magnetic resonance spectroscopy of extra-terrestrial methyl radical." Canadian Journal of Physics 87, no. 6 (June 2009): 709–19. http://dx.doi.org/10.1139/p09-010.

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The particular molecule discussed in some detail herein is the methyl radical, CH3, with emphasis on its potential extraterrestrial appearance. In earlier papers, including group-theoretical analysis, it was shown that the isotropic EPR spectra of free radical (S = 1/2) species XLn, where the n equivalent nuclei also have spin 1/2, have a more complicated form than disclosed by the usual (first-order) oversimplified analysis. In the present work, we focus on the magnetic resonance of such systems at or near zero external magnetic field, and on the spectra obtained both by perpendicular [Formula: see text] and parallel-field [Formula: see text] excitation. This work summarizes what is known about the spin-flip transitions of CH3, and predicts what likely will be observed (0–200 MHz, under various field and scan conditions), for the future use by astrophysicists.

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Haverd, V., M. R. Raupach, P. R. Briggs, S. J. Davis, R. M. Law, C. P. Meyer, G. P. Peters, C. Pickett-Heaps, and B. Sherman. "The Australian terrestrial carbon budget." Biogeosciences 10, no. 2 (February 7, 2013): 851–69. http://dx.doi.org/10.5194/bg-10-851-2013.

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Abstract. This paper reports a study of the full carbon (C-CO2) budget of the Australian continent, focussing on 1990–2011 in the context of estimates over two centuries. The work is a contribution to the RECCAP (REgional Carbon Cycle Assessment and Processes) project, as one of numerous regional studies. In constructing the budget, we estimate the following component carbon fluxes: net primary production (NPP); net ecosystem production (NEP); fire; land use change (LUC); riverine export; dust export; harvest (wood, crop and livestock) and fossil fuel emissions (both territorial and non-territorial). Major biospheric fluxes were derived using BIOS2 (Haverd et al., 2012), a fine-spatial-resolution (0.05°) offline modelling environment in which predictions of CABLE (Wang et al., 2011), a sophisticated land surface model with carbon cycle, are constrained by multiple observation types. The mean NEP reveals that climate variability and rising CO2 contributed 12 &pm; 24 (1σ error on mean) and 68 &pm; 15 TgC yr−1, respectively. However these gains were partially offset by fire and LUC (along with other minor fluxes), which caused net losses of 26 &pm; 4 TgC yr−1 and 18 &pm; 7 TgC yr−1, respectively. The resultant net biome production (NBP) is 36 &pm; 29 TgC yr−1, in which the largest contributions to uncertainty are NEP, fire and LUC. This NBP offset fossil fuel emissions (95 &pm; 6 TgC yr−1) by 38 &pm; 30%. The interannual variability (IAV) in the Australian carbon budget exceeds Australia's total carbon emissions by fossil fuel combustion and is dominated by IAV in NEP. Territorial fossil fuel emissions are significantly smaller than the rapidly growing fossil fuel exports: in 2009–2010, Australia exported 2.5 times more carbon in fossil fuels than it emitted by burning fossil fuels.

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Dunlop, Jason A., and Russell J. Garwood. "Terrestrial invertebrates in the Rhynie chert ecosystem." Philosophical Transactions of the Royal Society B: Biological Sciences 373, no. 1739 (December 18, 2017): 20160493. http://dx.doi.org/10.1098/rstb.2016.0493.

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The Early Devonian Rhynie and Windyfield cherts remain a key locality for understanding early life and ecology on land. They host the oldest unequivocal nematode worm (Nematoda), which may also offer the earliest evidence for herbivory via plant parasitism. The trigonotarbids (Arachnida: Trigonotarbida) preserve the oldest book lungs and were probably predators that practiced liquid feeding. The oldest mites (Arachnida: Acariformes) are represented by taxa which include mycophages and predators on nematodes today. The earliest harvestman (Arachnida: Opiliones) includes the first preserved tracheae, and male and female genitalia. Myriapods are represented by a scutigeromorph centipede (Chilopoda: Scutigeromorpha), probably a cursorial predator on the substrate, and a putative millipede (Diplopoda). The oldest springtails (Hexapoda: Collembola) were probably mycophages, and another hexapod of uncertain affinities preserves a gut infill of phytodebris. The first true insects (Hexapoda: Insecta) are represented by a species known from chewing (non-carnivorous?) mandibles. Coprolites also provide insights into diet, and we challenge previous assumptions that several taxa were spore-feeders. Rhynie appears to preserve a largely intact community of terrestrial animals, although some expected groups are absent. The known fossils are (ecologically) consistent with at least part of the fauna found around modern Icelandic hot springs. This article is part of a discussion meeting issue ‘The Rhynie cherts: our earliest terrestrial ecosystem revisited’.

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Anaya, Christina, Andreas Schmidt-Rhaesa, Ben Hanelt, and Matthew G. Bolek. "A new species of Gordius (Phylum Nematomorpha) from terrestrial habitats in North America." ZooKeys 892 (November 27, 2019): 59–75. http://dx.doi.org/10.3897/zookeys.892.38868.

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Freshwater hairworms (class Gordiida) are members of the phylum Nematomorpha that use terrestrial arthropods as definitive hosts but reside as free-living adult worms in rivers, lakes, or streams. The genus Gordius consists of 90 described species, of which three species were described from freshwater habitats in North America. In this paper we describe a new species of Gordius from terrestrial habitats in Oklahoma, Texas, and Louisiana, United States. Oddly, each year hundreds of adult free-living worms appear after bouts of heavy rain on streets, sidewalks, and lawns during the winter season, when terrestrial arthropod hosts are not active. The new species is described based on morphological characters of adults and non-adult stages including the egg strings, eggs, larvae, and cysts. Adult males have a unique row of bristles on the ventral inner side of each tail lobe and a circular pattern of bristles on the terminal end of each lobe, which distinguishes them from all other described North American species of Gordius. The egg string, larval, and cyst morphology of this new species conform to previous descriptions of non-adult hairworm stages for the genus Gordius. However, the eggs of this new species of hairworm are unique, as they contain an outer shell separated by distinct space from a thick inner membrane. The consistent occurrence of this gordiid in terrestrial habitats, along with its distinct egg morphology, suggests that this new species of hairworm has a terrestrial life cycle.

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Pyae, A. B., N. N. Nyan Lin, and Z. Z. Zaw. "OPEN SOURCE AND AFFORDABLE TERRESTRIAL LASER SCANNER." International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLVI-2/W1-2022 (February 25, 2022): 451–58. http://dx.doi.org/10.5194/isprs-archives-xlvi-2-w1-2022-451-2022.

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Abstract. This paper explores the development of an affordable terrestrial laser scanner (TLS) system based on low-cost components and open source software. This paper enumerates components implemented and integrated in both hardware and software aspects. Primarily, the proposed system depends on Mid-40 LiDAR sensor and utilizes Point Cloud Library (PCL), Open Source Computer Vision Library (OpenCV) and Robotic Operating System (ROS) for system operation and data processing. Furthermore, this paper discusses sensor calibration and fusion methods available and implemented in the processing pipeline. The goal of this work is to produce an open source package of software system and hardware designs of a robust version of the TLS system that can be shared and easily reproduced by individuals and communities for their applications.

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Ebolese, D., G. Dardanelli, M. Lo Brutto, and R. Sciortino. "3D SURVEY IN COMPLEX ARCHAEOLOGICAL ENVIRONMENTS: AN APPROACH BY TERRESTRIAL LASER SCANNING." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2 (May 30, 2018): 325–30. http://dx.doi.org/10.5194/isprs-archives-xlii-2-325-2018.

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The survey of archaeological sites by appropriate geomatics technologies is an important research topic. In particular, the 3D survey by terrestrial laser scanning has become a common practice for 3D archaeological data collection. Even if terrestrial laser scanning survey is quite well established, due to the complexity of the most archaeological contexts, many issues can arise and make the survey more difficult.<br> The aim of this work is to describe the methodology chosen for a terrestrial laser scanning survey in a complex archaeological environment according to the issues related to the particular structure of the site. The developed approach was used for the terrestrial laser scanning survey and documentation of a part of the archaeological site of Elaiussa Sebaste in Turkey. The proposed technical solutions have allowed providing an accurate and detailed 3D dataset of the study area. In addition, further products useful for archaeological analysis were also obtained from the 3D dataset of the study area.

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Lussiana, Thibault, Cyrille Gindre, Kim Hébert-Losier, Yoshimasa Sagawa, Philippe Gimenez, and Laurent Mourot. "Similar Running Economy With Different Running Patterns Along the Aerial-Terrestrial Continuum." International Journal of Sports Physiology and Performance 12, no. 4 (April 2017): 481–89. http://dx.doi.org/10.1123/ijspp.2016-0107.

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Purpose:No unique or ideal running pattern is the most economical for all runners. Classifying the global running patterns of individuals into 2 categories (aerial and terrestrial) using the Volodalen method could permit a better understanding of the relationship between running economy (RE) and biomechanics. The main purpose was to compare the RE of aerial and terrestrial runners.Methods:Two coaches classified 58 runners into aerial (n = 29) or terrestrial (n = 29) running patterns on the basis of visual observations. RE, muscle activity, kinematics, and spatiotemporal parameters of both groups were measured during a 5-min run at 12 km/h on a treadmill. Maximal oxygen uptake (V̇O2max) and peak treadmill speed (PTS) were assessed during an incremental running test.Results:No differences were observed between aerial and terrestrial patterns for RE, V̇O2max, and PTS. However, at 12 km/h, aerial runners exhibited earlier gastrocnemius lateralis activation in preparation for contact, less dorsiflexion at ground contact, higher coactivation indexes, and greater leg stiffness during stance phase than terrestrial runners. Terrestrial runners had more pronounced semitendinosus activation at the start and end of the running cycle, shorter flight time, greater leg compression, and a more rear-foot strike.Conclusions:Different running patterns were associated with similar RE. Aerial runners appear to rely more on elastic energy utilization with a rapid eccentric-concentric coupling time, whereas terrestrial runners appear to propel the body more forward rather than upward to limit work against gravity. Excluding runners with a mixed running pattern from analyses did not affect study interpretation.

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Wright, Sean E., and Marc A. Rosen. "Exergetic Efficiencies and the Exergy Content of Terrestrial Solar Radiation." Journal of Solar Energy Engineering 126, no. 1 (February 1, 2004): 673–76. http://dx.doi.org/10.1115/1.1636796.

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In the field of solar engineering the practical performance of solar energy conversion devices is generally evaluated strictly on an energy (first law) basis. However, the second law of thermodynamics determines the maximum work potential or exergy content of radiative fluxes independent of any conceptual device. The work in this paper quantifies the effect of directional and spectral distribution of terrestrial solar radiation (SR) on its exergy content. This is particularly important as the thermodynamic character of terrestrial SR is very different from that of blackbody radiation (BR). Exergetic (second law) efficiencies compare the work output of a device to the exergy content of the radiative source flux rather than its energy flux. As a result, exergetic efficiencies reveal that the performance of devices in practice is always better than what is indicated by the corresponding energy efficiency. The results presented in this paper introduce the benefits of using exergy analysis for solar cell design, performance evaluation and optimization.

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Reinking, Roggenbuck, and Even-Tzur. "Estimating Wave Direction Using Terrestrial GNSS Reflectometry." Remote Sensing 11, no. 9 (April 30, 2019): 1027. http://dx.doi.org/10.3390/rs11091027.

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The signal-to-noise ratio (SNR) data are part of the global navigation satellite systems (GNSS) observables. In a marine environment, the oscillation of the SNR data can be used to derive reflector heights. Since the attenuation of the SNR oscillation is related to the roughness of the sea surface, the significant wave height (SWH) of the water surface can be calculated from the analysis of the attenuation. The attenuation depends additionally on the relation between the coherent and the incoherent part of the scattered power. The latter is a function of the correlation length of the surface waves. Since the correlation length changes with respect to the direction of the line of sight relative to the wave direction, the attenuation must show an anisotropic characteristic. In this work, we present a method to derive the wave direction from the anisotropy of the attenuation of the SNR data. The method is investigated based on simulated data, as well by the analysis of experimental data from a GNSS station in the North Sea.

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Taylor-Burt, Kari R., and Andrew A. Biewener. "Aquatic and terrestrial takeoffs require different hindlimb kinematics and muscle function in mallard ducks." Journal of Experimental Biology 223, no. 16 (June 25, 2020): jeb223743. http://dx.doi.org/10.1242/jeb.223743.

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ABSTRACTMallard ducks are capable of performing a wide range of behaviors including nearly vertical takeoffs from both terrestrial and aquatic habitats. The hindlimb plays a key role during takeoffs from both media. However, because force generation differs in water versus on land, hindlimb kinematics and muscle function are likely modulated between these environments. Specifically, we hypothesize that hindlimb joint motion and muscle shortening are faster during aquatic takeoffs, but greater hindlimb muscle forces are generated during terrestrial takeoffs. In this study, we examined the hindlimb kinematics and in vivo contractile function of the lateral gastrocnemius (LG), a major ankle extensor and knee flexor, during takeoffs from water versus land in mallard ducks. In contrast to our hypothesis, we observed no change in ankle angular velocity between media. However, the hip and metatarsophalangeal joints underwent large excursions during terrestrial takeoffs but exhibited almost no motion during aquatic takeoffs. The knee extended during terrestrial takeoffs but flexed during aquatic takeoffs. Correspondingly, LG fascicle shortening strain, shortening velocity and pennation angle change were greater during aquatic takeoffs than during terrestrial takeoffs because of the differences in knee motion. Nevertheless, we observed no significant differences in LG stress or work, but did see an increase in muscle power output during aquatic takeoffs. Because differences in the physical properties of aquatic and terrestrial media require differing hindlimb kinematics and muscle function, animals such as mallards may be challenged to tune their muscle properties for movement across differing environments.

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Elseberg, J., D. Borrmann, J. Schauer, A. Nüchter, D. Koriath, and U. Rautenberg. "A sensor skid for precise 3D modeling of production lines." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences II-5 (May 28, 2014): 117–22. http://dx.doi.org/10.5194/isprsannals-ii-5-117-2014.

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Motivated by the increasing need of rapid characterization of environments in 3D, we designed and built a sensor skid that automates the work of an operator of terrestrial laser scanners. The system combines terrestrial laser scanning with kinematic laser scanning and uses a novel semi-rigid SLAMmethod. It enables us to digitize factory environments without the need to stop production. The acquired 3D point clouds are precise and suitable to detect objects that collide with items moved along the production line.

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Raabová, Lenka, Josef Elster, and Ľubomír Kováčik. "Phototrophic microflora colonizing substrates of man-made origin in Billefjorden Region, Central Svalbard." Czech Polar Reports 6, no. 1 (January 1, 2016): 21–30. http://dx.doi.org/10.5817/cpr2016-1-3.

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Substrates created by human have a significant impact on Arctic terrestrial environment. These substrates are new potential niche for microbial biota, which may have several essential chemical agents supporting microbial growth. Wood, concrete, brick, ceramic and other different building materials, which have been introduced by human in this iso-lated environment, are colonized with terrestrial and aero-terrestrial microorganisms living in the natural niches near the substrates like soil, rocks, etc., but these materials newly-introduced to Svalbard terrestrial ecosystems can also work as vectors for invasion of new species into the environment. We have collected different types of artificial substrates mainly in the region of Petuniabukta bay and studied the species composition of microbial phototrophs living there. A total of 25 taxa of cyanobacteria and algae were documented on different types of substrates like brick walls, concrete, glass, iron, wood and plastic. A commonality in species diversity was observed with similar substrates in temperate climatic regions. Fottea stichococcoides, Sphaerococcomyxa olivacea, Polysphaera composita and Diplosphaera chodatii were first time recorded from Svalbard Archipelago.

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Do, Dinh-Thuan, Anh-Tu Le, Rupak Kharel, Adão Silva, and Mohammad Abu Shattal. "Hybrid Satellite-Terrestrial Relay Network: Proposed Model and Application of Power Splitting Multiple Access." Sensors 20, no. 15 (August 1, 2020): 4296. http://dx.doi.org/10.3390/s20154296.

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The development of hybrid satellite-terrestrial relay networks (HSTRNs) is one of the driving forces for revolutionizing satellite communications in the modern era. Although there are many unique features of conventional satellite networks, their evolution pace is much slower than the terrestrial wireless networks. As a result, it is becoming more important to use HSTRNs for the seamless integration of terrestrial cellular and satellite communications. With this intent, this paper provides a comprehensive performance evaluation of HSTRNs employing non-orthogonal multiple access technique. The terrestrial relay is considered to be wireless-powered and harvests energy from the radio signal of the satellite. For the sake of comparison, both amplify-and-forward (AF) and decode-and-forward (DF) relaying protocols are considered. Subsequently, the closed-form expressions of outage probabilities and ergodic capacities are derived for each relaying protocol. Extensive simulations are performed to verify the accuracy of the obtained closed-form expressions. The results provided in this work characterize the outage and capacity performance of such a HSTRN.

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Carvalho, Carla, Kita Macario, Maria Isabela De Oliveira, Fabiana Oliveira, Ingrid Chanca, Eduardo Alves, Rosa Souza, Orangel Aguilera, and Katerina Douka. "Potential Use of Archaeological Snail Shells for the Calculation of Local Marine Reservoir Effect." Radiocarbon 57, no. 3 (2015): 459–67. http://dx.doi.org/10.2458/azu_rc.57.18365.

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Shellmounds are archaeological sites found across the Brazilian coast and form an important record of the human occupation of this area during the Holocene. The presence of both terrestrial and marine remains within the same archaeological context enables the comparison of different carbon reservoirs. There is only a small number of similar studies for the coast of south-southeastern Brazil. Previous work was based on the analysis of pre-bomb shells from museum collections and paired charcoal/marine shells from archaeological sites. This article assesses the potential use of terrestrial shells as representative of atmospheric carbon reservoir in the calculation of the marine reservoir effect (MRE) of the southeastern Brazilian coast. The presence of both terrestrial and marine shells over several archaeological layers represents a great potential for calculating reservoir corrections and their temporal variation.

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Pawłowicz, Joanna A. "The TLS technique as a way of identification and measurement of damaged elements of a historic sacral building." MATEC Web of Conferences 284 (2019): 08007. http://dx.doi.org/10.1051/matecconf/201928408007.

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3D terrestrial laser scanning (TLS) is a modern measurement technique which enables to obtain a large amount of data in short time. The gathered data is very detailed, thus the scope of its use is vast. Therefore scanners other measurement devices which results in considerable acceleration of stock-taking work. This approach enables to prepare a documentation of a building or to make an assessment of its technical condition using only a 3D cloud of points. Additionally, flexibility of data and advanced computer programmes make it possible to use such data in many sectors, not only in the building trade. The paper shows the issue of using a 3D terrestrial laser scanner ant the TLS (Terrestrial Laser Scanning) technique for identification and measurement of damaged elements on the example of a historical sacral building.

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Butcher, A. R., J. K. Brealey, D. I. Grove, and R. B. Dymock. "Brachylaima cribbi(Digenea: Brachylaimidae): scanning electron microscopical observations of the life-cycle stages." Journal of Helminthology 76, no. 3 (September 2002): 207–15. http://dx.doi.org/10.1079/joh2002119.

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AbstractBrachylaima cribbiis a recently described species of terrestrial trematode that infects mammals and birds with helicid land snails as its first and second intermediate hosts. The adult worm is 2.5–6.0 mm long by 0.5–0.8 mm wide being a long slender cylindrical worm with oral and ventral suckers in the anterior quarter and genital pore in the posterior quarter. Scanning electron microscopy shows that there is a dense covering of tegumental spines at the anterior end which diminishes towards the posterior extremities of the worm. Development of spines was observed in juvenile and mature adult worms. In young worms 1–3 weeks post infection (wpi) spines appear as buds with a serrated edge each having 1–4 spikes per spine. As the worm ages the spines broaden and by 5 wpi the number of spikes per spine increases to an average of 8.1. The serial development of oral sucker papillae in the cercaria, metacercaria and adult worm was observed with the finding of an elongated papilla with a bifurcated tip on the cercaria becoming a shorter and thicker elongated papilla with a large central stoma on the metacercaria. In the adult worm, this papilla becomes dome-shaped with a small central stoma. For some of these papillae a cilium could be seen extended from the central stoma. Other life-cycle stages illustrated were the hatched egg with an extruded egg membrane minus an operculum and a portion of the branched sporocyst dissected from the digestive gland of the land snailTheba pisanashowing a terminal birth pore. Scanning electron microscopy morphological features of the adult worm observed for the first time in aBrachylaimawere the unarmed cirrus extended from the genital pore with released sperm present and the Laurer's canal opening visible in tegumental folds on the dorsal surface approximately 300 μm posterior to the genital pore.

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Lang, Shirley A., Naim Saglam, Joseph Kawash, and Daniel H. Shain. "Punctuated invasion of water, ice, snow and terrestrial ecozones by segmented worms (Oligochaeta: Enchytraeidae: Mesenchytraeus )." Proceedings of the Royal Society B: Biological Sciences 284, no. 1864 (October 11, 2017): 20171081. http://dx.doi.org/10.1098/rspb.2017.1081.

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Segmented worms (Annelida) are among the most successful animal inhabitants of extreme environments worldwide. An unusual group of enchytraeid oligochaetes of genus Mesenchytraeus are abundant in the Pacific northwestern region of North America and occupy geographically proximal ecozones ranging from low elevation rainforests and waterways to high altitude glaciers. Along this altitudinal transect, Mesenchytraeus representatives from disparate habitat types were collected and subjected to deep mitochondrial and nuclear phylogenetic analyses. Our data identify significant topological discordance among gene trees, and near equivalent interspecific divergence levels indicative of a rapid radiation event. Collectively, our results identify a Mesenchytraeus ‘explosion’ coincident with mountain building in the Pacific northwestern region that gave rise to closely related aquatic, ice, snow and terrestrial worms.

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Sotiriadis, Sotiris, Anne-Sophie Libert, and Sean N. Raymond. "Formation of terrestrial planets in eccentric and inclined giant planet systems." Astronomy & Astrophysics 613 (May 2018): A59. http://dx.doi.org/10.1051/0004-6361/201731260.

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Aims. Evidence of mutually inclined planetary orbits has been reported for giant planets in recent years. Here we aim to study the impact of eccentric and inclined massive giant planets on the terrestrial planet formation process, and investigate whether it can possibly lead to the formation of inclined terrestrial planets. Methods. We performed 126 simulations of the late-stage planetary accretion in eccentric and inclined giant planet systems. The physical and orbital parameters of the giant planet systems result from n-body simulations of three giant planets in the late stage of the gas disc, under the combined action of Type II migration and planet-planet scattering. Fourteen two- and three-planet configurations were selected, with diversified masses, semi-major axes (resonant configurations or not), eccentricities, and inclinations (including coplanar systems) at the dispersal of the gas disc. We then followed the gravitational interactions of these systems with an inner disc of planetesimals and embryos (nine runs per system), studying in detail the final configurations of the formed terrestrial planets. Results. In addition to the well-known secular and resonant interactions between the giant planets and the outer part of the disc, giant planets on inclined orbits also strongly excite the planetesimals and embryos in the inner part of the disc through the combined action of nodal resonance and the Lidov–Kozai mechanism. This has deep consequences on the formation of terrestrial planets. While coplanar giant systems harbour several terrestrial planets, generally as massive as the Earth and mainly on low-eccentric and low-inclined orbits, terrestrial planets formed in systems with mutually inclined giant planets are usually fewer, less massive (<0.5 M⊕), and with higher eccentricities and inclinations. This work shows that terrestrial planets can form on stable inclined orbits through the classical accretion theory, even in coplanar giant planet systems emerging from the disc phase.

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Hughes, Kevin A., and M. Roger Worland. "Spatial distribution, habitat preference and colonization status of two alien terrestrial invertebrate species in Antarctica." Antarctic Science 22, no. 3 (January 22, 2010): 221–31. http://dx.doi.org/10.1017/s0954102009990770.

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AbstractThe introduction of invasive species is one of the greatest threats to Earth’s biodiversity, as they can reduce native biodiversity and alter ecosystem structure and function. Currently, the only two known non-native terrestrial invertebrates in Antarctica are the chironomid midge Eretmoptera murphyi and the enchytraeid worm Christensenidrilus blocki. These invertebrates were probably introduced to ground near Signy Research Station, South Orkney Islands, during transplantation experiments in the late 1960s. Between 2007 and 2009, this study surveyed the area around the introduction site for midge larvae and worms to assess any change over the last four decades in their spatial distribution, habitat preference and colonization status. Eretmoptera murphyi was found in concentrations up to 4.1 × 105 larvae m-2 (mean 2.1 × 104 larvae m-2) at distances of up to 220 m from the probable introduction site (c. 35 000 m2), while C. blocki was only found close to the introduction site in low numbers. Significantly more E. murphyi larvae were found in peat and dead organic material (3.34 × 104 m-2) than in stony soil and gravel (1.52 × 104 m-2) or living moss and other plant material (1.16 × 104 m-2). Eretmoptera murphyi can no longer be considered a persistent alien as it clearly expanding its distribution, while C. blocki remains a persistent alien species.

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Langor, David W. "The diversity of terrestrial arthropods in Canada." ZooKeys 819 (January 24, 2019): 9–40. http://dx.doi.org/10.3897/zookeys.819.31947.

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Based on data presented in 29 papers published in theBiota of CanadaSpecial Issue of ZooKeys and data provided herein about Zygentoma, more than 44,100 described species of terrestrial arthropods (Arachnida, Myriapoda, Insecta, Entognatha) are now known from Canada. This represents more than a 34% increase in the number of described species reported 40 years ago (Danks 1979a). The most speciose groups are Diptera (9620 spp.), Hymenoptera (8757), and Coleoptera (8302). Less than 5% of the fauna has a natural Holarctic distribution and an additional 5.1% are non-native species. A conservatively estimated 27,000–42,600 additional species are expected to be eventually discovered in Canada, meaning that the total national species richness is ca. 71,100–86,700 and that currently 51–62% of the fauna is known. Of the most diverse groups, those that are least known, in terms of percent of the Canadian fauna that is documented, are Acari (31%), Thysanoptera (37%), Hymenoptera (46%), and Diptera (32–65%). All groups but Pauropoda have DNA barcodes based on Canadian material. More than 75,600 Barcode Index Numbers have been assigned to Canadian terrestrial arthropods, 63.5% of which are Diptera and Hymenoptera. Much work remains before the Canadian fauna is fully documented, and this will require decades to achieve. In particular, greater and more strategic investment in surveys and taxonomy (including DNA barcoding) is needed to adequately document the fauna.

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Lelieveld, J., G. –J Roelofs, L. Ganzeveld, J. Feichter, and H. Rodhe. "Terrestrial sources and distribution of atmospheric sulphur." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 352, no. 1350 (February 28, 1997): 149–58. http://dx.doi.org/10.1098/rstb.1997.0010.

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The general circulation model ECHAM has been coupled to a chemistry and sulphur cycle model to study the impact of terrestrial, i.e. mostly anthropogenic sulphur dioxide (SO 2 ), sources on global distributions of sulphur species in the atmosphere. We briefly address currently available source inventories. It appears that global estimates of natural emissions are associated with uncertainties up to a factor of 2, while anthropogenic emissions have uncertainty ranges of about +/− 30 per cent. Further, some recent improvements in the model descriptions of multiphase chemistry and deposition processes are presented. Dry deposition is modelled consistently with meteorological processes and surface properties. The results indicate that surface removal of SO 2 is less efficient than previously assumed, and that the SO 2 lifetime is thus longer. Coupling of the photochemistry and sulphur chemistry schemes in the model improves the treatment of multiphase processes such as oxidant (hydrogen peroxide) supply in aqueous phase SO 2 oxidation. The results suggest that SO 2 oxidation by ozone (O 3 ) in the aqueous phase is more important than indicated in earlier work. However, it appears that we still overestimate atmospheric SO 2 concentrations near the surface in the relatively polluted Northern Hemisphere. On the other hand, we somewhat underestimate sulphate levels in these regions, which suggests that additional heterogeneous reaction mechanisms, e.g. on aerosols, enhance SO 2 oxidation.

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Figueira, J. E. C., F. A. Mourão, and A. S. Coelho. "Habitat heterogeneity and climatic seasonality structure the avifauna trophic guilds in the Brazilian Pantanal wetland." Canadian Journal of Zoology 89, no. 12 (December 2011): 1206–13. http://dx.doi.org/10.1139/z11-099.

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Landscape heterogeneity and annual flood pulses characterize the Brazilian Pantanal, the largest floodplain in South America. The objective of this work was to explain spatial and temporal variations in the trophic structure of a bird assemblage consisting of 316 species of terrestrial and aquatic birds, out of which 88 are visitors. The food items potentially consumed by these species were combined into 12 trophic guilds and were compared based on habitats (terrestrial or aquatic), periods of the year, and visitor or resident species. Nonmetric multidimensional scaling was used to determine which trophic guilds characterize the different habitats and months. The habitats were separated into a gradient of trophic guild similarity ranging from woodlands to purely aquatic, with swamps and floodable fields in intermediate positions. Species that consume invertebrates and plants predominate in the terrestrial habitats, whereas the consumption of terrestrial and (or) aquatic invertebrates, vertebrates, and plants predominate in the aquatic habitats. The monthly similarities in trophic structure vary with rainfall, and the period of receding waters is characterized by an increase in the number of species in guilds that consume nectar, invertebrates, vertebrates, and (or) plant parts obtained or captured in the drying landscape and terrestrial habitats. Visitor species do not exploit new resource types; instead they accommodate themselves in the pre-existing trophic guilds.

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Silva, Caroline, Átila de Oliveira, and Marcelo Fernandes. "Validation of a Dynamic Planning Navigation Strategy Applied to Mobile Terrestrial Robots." Sensors 18, no. 12 (December 7, 2018): 4322. http://dx.doi.org/10.3390/s18124322.

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This work describes the performance of a DPNA-GA (Dynamic Planning Navigation Algorithm optimized with Genetic Algorithm) algorithm applied to autonomous navigation in unknown static and dynamic terrestrial environments. The main aim was to validate the functionality and robustness of the DPNA-GA, with variations of genetic parameters including the crossover rate and population size. To this end, simulations were performed of static and dynamic environments, applying the different conditions. The simulation results showed satisfactory efficiency and robustness of the DPNA-GA technique, validating it for real applications involving mobile terrestrial robots.

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Journal articles on the topic 'Terrestial worm'

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