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Tillage conservation practices (CA), traditional agriculture (TA), and liming influence soil properties and crop yield. However, it is essential to demonstrate which tillage and liming practices improve soil properties and forage corn yield. This study compared soil properties and forage corn production in two tillage systems with the addition of dolomite and lime, which formed four treatments. The tillage in the first three days surpassed the TA soil CO2 emission, with 64.8% more CO2 than in the CA soil, and the TA hydraulic conductivity and bulk density were more suitable than those in the CA soil. The CA soil had 233 earthworms m−2 more than in TA. The TA green forage corn yielded 6.45 t ha−1 more than in CA, with a higher P, Ca, and Mg foliar content than in CA, but in the CA, the foliar N and K were higher than in TA. The liming increased soil cations (except K), highlighting the lime on dolomite with—52% Al and + 4.85 t ha−1 of forage corn compared to the control. Soil CO2 emission was far lower in CA than in TA, with a slightly lower forage yield, and other soil properties were improved, meaning lower land preparation costs and time savings than in TA. Lime improved acidic soil faster than dolomite, generating higher forage yields. [ABSTRACT FROM AUTHOR]

The Late Ordovician Tafilalt Biota of the Moroccan Anti-Atlas includes a diverse range of soft-bodied organisms, including palaeoscolecids, paropsonemid eldonioids, graptolites and cheloniellid arthropods, as well as a rich assemblage of mineralised taxa, among them conulariids, trilobites and echinoderms, often found as articulated skeletons. The new fossil locality, not far from the original Bou Nemrou site, has produced two new palaeoscolecid taxa, the new genus and species Anguiscolex africanus and the new species Wronascolex superstes. They are preserved as compression fossils in fine-grained mudstones, where the original phosphatic sclerites have been diagenetically substituted by pyrite and later weathered to iron oxides, giving them a characteristic rusty colour. This area of Gondwana was located adjacent to the Late Ordovician South Pole and both Anguiscolex africanus gen. et sp. nov. and Wronascolex superstes sp. nov. present a degree of polar gigantism, which has been suggested for other taxa in such high palaeolatitudes such as bryozoans, conulariids, trilobites and radiodonts. Lastly, the occurrence of Wronascolex extends the distribution of this typically Cambrian taxon into the Late Ordovician, indicating a total range for the genus exceeding 60 million years, more than any other palaeoscolecid genus described to date. [ABSTRACT FROM AUTHOR]

This research is based on the effect of actions aimed at addressing diversity, equity and inclusion carried out by private sector companies of Costa Rica in 2022, in the following Sustainable Development Goals: 4 -Quality Education, 5 -Gender Equality, 8 -Decent Work and Economic Growth, 10 -Reduction of Inequalities and 16 -Peace, Justice and Solid Institutions, in Costa Rica, during the year 2022 and shows the results of a study based on the application of a mixed methodology. It consists of a quantitative and qualitative analysis with the support of data collection instruments. The instrument used for the collection of quantitative data is a questionnaire. The results obtained from the data collection instrument suggest that private sector companies of Costa Rica that manage the thematic axis of diversity, equity, and inclusion, are directly related to some of the Sustainable Development Goals defined by the United Nations Organization in the 2030 Agenda. It is recommended that companies in the private sector of Costa Rica carry out a meticulous work that evidences the effect that their actions have in the relational dimension of diversity, equity, and inclusion, with the afore-mentioned Sustainable Development Goals. This research offers an-input for these companies to demonstrate the existence of this relationship and its contribution to Costa Rica with the achievement of some Sustainable Development Goals. [ABSTRACT FROM AUTHOR]

Debris discs consist of belts of bodies ranging in size from dust grains to planetesimals; these belts are visible markers of planetary systems around other stars that can reveal the influence of extrasolar planets through their shape and structure. Two key stirring mechanisms – self-stirring by planetesimals and secular perturbation by an external giant planet – have been identified to explain the dynamics of planetesimal belts; their relative importance has been studied independently, but are yet to be considered in combination. In this work, we perform a suite of 286  N -body simulations exploring the evolution of debris discs over 1 Gyr, combining the gravitational perturbations of both dwarf planets embedded in the discs, and an interior giant planet. Our systems were somewhat modelled after the architecture of the outer Solar system: a Solar mass star, a single massive giant planet at 30 au (M GP = 10 to 316 M⊕), and a debris disc formed by 100 massive dwarf planets and 1000 massless particles (M DD = 3.16 to 31.6 M⊕). We present the evolution of both the disc and the giant planet after 1 Gyr. The time evolution of the average eccentricity and inclination of the disc is strongly dependent on the giant planet mass as well as on the remaining disc mass. We also found that efficient stirring is achieved even with small disc masses. In general, we find that a mixed mechanism is more efficient in the stirring of cold debris discs than either mechanism acting in isolation. [ABSTRACT FROM AUTHOR]

Solutans were among the most enigmatic pre-radial and asymmetric echinoderms. A new species Dehmicystis ariasi sp. nov. is described from the upper part of the Llagarinos Formation, lower Ludlow (Silurian) of Northwest Spain. This is the first solutan formally described from Iberia and the first from the Silurian worldwide. Dehmicystis was previously known based on a small number of poorly preserved specimens from the Emsian, Lower Devonian Hunsrück Slate of Germany. New observations based on the newly studied material suggest that Dehmicystis displayed a feeding appendage facing towards the substrate, and the periproct on the opposite face of the theca. Comparisons with other solutans and new data suggest that Dehmicystis was a detritus feeder that moved over the substrate capturing organic particles from the sediment with a single feeding arm. [ABSTRACT FROM AUTHOR]

Solutans were among the most enigmatic pre-radial and asymmetric echinoderms. A new species Dehmicystis ariasi sp. nov. is described from the upper part of the Llagarinos Formation, lower Ludlow (Silurian) of Northwest Spain. This is the first solutan formally described from Iberia and the first from the Silurian worldwide. Dehmicystis was previously known based on a small number of poorly preserved specimens from the Emsian, Lower Devonian Hunsrück Slate of Germany. New observations based on the newly studied material suggest that Dehmicystis displayed a feeding appendage facing towards the substrate, and the periproct on the opposite face of the theca. Comparisons with other solutans and new data suggest that Dehmicystis was a detritus feeder that moved over the substrate capturing organic particles from the sediment with a single feeding arm. [ABSTRACT FROM AUTHOR]

The problematic colonial organism Webbyites has previously been considered to be a hydroid (phylum Cnidaria). In this paper, we describe a new species, Webbyites felix sp. nov., from the Early Ordovician Fezouata Konservat-Lagerstätte of Morocco. One specimen preserves some soft-tissue zooid remains. The presence of a stolon system in the new species and the type species indicates that Webbyites is a benthic graptolite. Webbyites lacks bithecae; thus, it is not a dendroid graptolite. [ABSTRACT FROM AUTHOR]

Human–robot interaction tasks have seen an increased interest in recent years, leading to the need for new proposals both for the design of new robotic systems and for their control and security schemes. In this regard, this work proposes a first approach to impedance control for robot manipulators with bounded inputs which aims to achieve safe human–robot interaction. The proposed scheme has a nonlinear proportional–derivative structure with compensation (PD + ) based on the robot model, makes use of generalized saturation functions to generate bounded control actions, and includes an external torque compensation term based on the user's electromyographic information. One of the main advantages of this proposal is that the human–robot interaction is defined in the joint space, which avoids singularities, since the robot works within its natural coordinates and the torque applied by the user is estimated at a joint level. The advantage of the novel control scheme can be demonstrated by the stability analysis of the closed-loop system equilibrium point, as well as by comparative analysis of the simulation results. [ABSTRACT FROM AUTHOR]

Silty noduliferous shales in the lower part of the Middle Ordovician (late Darriwilian 2) Taddrist Formation in the central Moroccan Anti-Atlas contain a unique assemblage of conulariids consisting of one species each of Archaeoconularia Bouček, 1939, Glyptoconularia Sinclair, 1952, and Pseudoconularia Bouček, 1939. Glyptoconularia antiatlasica new species, currently represented by a single three-dimensional specimen, is the first member of this extremely rare, highly autapomorphic genus to be described from outside of cratonic North America as well as the first Glyptoconularia from the Middle Ordovician. Pseudoconularia cf. P. grandissima (Barrande, 1867) and Archaeoconularia cf. A. exquisita (Barrande, 1867) most closely resemble species previously described from Middle and Upper Ordovician strata in the Prague Basin (Czech Republic), then located adjacent to North Africa. Anaconularia anomala (Barrande, 1867), previously known from the Upper Ordovician (Sandbian) Libeň and Letná formations in the Prague Basin, is documented for the first time from the Upper Ordovician (Katian) Upper Tioririne Formation of Morocco. In addition to extending the known stratigraphical and paleogeographical ranges of these conulariids, results of the present investigation add to the list of invertebrate taxa that appear to have originated during Early or Mid-Ordovician times in peri-Gondwana or south-polar Gondwana, and then migrated to the eastern margin of Laurentia, arriving there along with other cool-water taxa during the Sandbian-Katian transition. UUID: http://zoobank.org/9ea5051b-cff5-4911-861a-531db4f45883 [ABSTRACT FROM AUTHOR]

The distinctive set of Saturnian small satellites, Aegaeon, Methone, Anthe, and Pallene, constitutes an excellent laboratory to understand the evolution of systems immersed in co-orbital dusty rings/arcs, subjected to perturbations from larger satellites and non-gravitational forces. In this work, we carried out a comprehensive numerical exploration of the long-term evolution of Pallene and its ring. Through frequency map analysis, we characterized the current dynamical state around Pallene. A simple tidal evolution model serves to set a time frame for the current orbital configuration of the system. With detailed short- and long-term N -body simulations we determine whether Pallene is currently in resonance with one or more of six of Saturn's major moons. We analysed a myriad of resonant arguments extracted from the direct and indirect parts of the disturbing function, finding that Pallene is not in mean motion resonance from the present up to 5 Myr into the future; none the less, some resonant arguments exhibit intervals of libration and circulation at different time-scales and moon pairings. We studied the dynamical evolution of micrometric particles forming the ring, considering gravitational and non-gravitational forces. Non-gravitational forces are responsible for particles vertical excursions and outward migration. By estimating the satellite's mass production rate, we find that Pallene could be responsible for keeping its ring in steady-state only if it is mainly composed of large micrometre-sized particles. If mainly composed of particles with a few micrometres for which Pallene is the only source, the ring will spread out, both radially and vertically, until it finally disappears. [ABSTRACT FROM AUTHOR]

The record of Middle Ordovician (Oretanian, ca. Darriwilian 2) hyolithids from the Ossa Morena Zone of the Iberian Massif in southwestern Spain is increased with the recognition of Robardetlites sevillanus n. gen. n. sp., Andalucilites parvulus n. gen. n. sp., Pauxillites desolatus n. sp., Leolites malinkyi Marek and Gutiérrez-Marco n. sp., and Cavernolites sp. in that region. Andalucilites n. gen. and Robardetlites n. gen. are endemic whereas the other genera are known from coeval strata in the Barrandian region in central Europe, France, and Morocco, giving this assemblage a decidedly "Mediterranean province" character. The discovery of Pauxillites, Leolites, and Cavernolites in Iberia extends their geographic ranges to that region, and Leolites from this area extends its stratigraphic range downward, making its occurrence in Iberia the oldest known for that genus. UUID: http://zoobank.org/f5b29223-6dac-4c7e-8851-551e634da667 [ABSTRACT FROM AUTHOR]

Phragmolites lissoni new species is described from 11 specimens found in the Sandbian Calapuja Formation near Calapuja in Peru. The deposits are part of the Central Andean Basin. This is the hitherto only systematically described Ordovician gastropod from Peru. The species is from a brachiopod-dominated siliciclastic sequence and is associated with bryozoans. Most specimens are preserved as external molds, but latex casts yield excellent details of shell ornamentation and are used as a basis for evaluating this feature in the genus. The characteristic ornamentation of Phragmolites should be called corrugated lamellae, and the individual elements on these should be referred to as flutes. A descriptive terminology for these is suggested. The development and shape of the corrugated lamellae and flutes could be biomechanical process. A second component in lamellar formation is the alternation between regular incremental growth and formation of a lamella. Phragmolites is mainly found in shallow-water carbonate facies from tropical latitudes in the Sandbian and a mid-latitude presence in Peru is unexpected. Brachiopods from the same section in Calapuja show affinities with faunas of the Mediterranean margin of Gondwana but also weak links with Avalonia. Phragmolites is found abundantly in deeper-water facies in Laurentia, and a broad tolerance to facies and temperature and possible planktotrophy might have allowed a wide geographical dispersal of the genus. The scant record of Ordovician gastropods in the Central Andean Basin precludes comparison with the disparate record of the Ordovician gastropod taxa from the Precordillera, which do not include Phragmolites. UUID: http://zoobank.org/References/fbd7a43e-a610-42fd-a31d-b1a16fa69c9b [ABSTRACT FROM AUTHOR]

The order Intejocerida is an enigmatic, short-lived cephalopod taxon known previously only from Early–Middle Ordovician beds of Siberia and the United States. Here we report a new genus, Cabaneroceras, and a new species, C. aznari, from Middle Ordovician strata of central Spain. This finding widens the paleogeographic range of the order toward high-paleolatitudinal areas of peri-Gondwana. A curved conch, characteristic for the new genus, was previously unknown from members of the Intejocerida. UUID: http://zoobank.org/21f0a09c-5265-4d29-824b-6b105d36b791 [ABSTRACT FROM AUTHOR]

Potato (Solanum tuberosum) is considered a staple in the diet of hundreds of people. In Colombia, during 2017, a production of 2.8 million tons was registered, being the variety Diacol Capiro most planted for industrial processing in the departments of Cundinamarca, Boyacá and Nariño. The crop is sensitive to water deficit and it is the most limiting factor in production, therefore, irrigation is an essential practice which is being done by spraying with low efficiency, while drip irrigation can achieve efficiencies close to 90 %. An experiment was carried out under field conditions aiming to evaluate the effect of two irrigation systems (drip vs spray) on the production, quality, and efficient use of water in the Diacol Capiro variety potato crop in the municipality of Toca, Boyacá. A completely randomized experimental design was used with 2 treatments corresponding to each irrigation system and 3 repetitions. At 28 days after sowing (das) sprouting percentage, yield and quality of tubers were measured and harvest and efficient water use was calculated for fresh tubers. Statistical differences were observed for the evaluated treatments (p <0.05) in germination and efficient use of water; other variables did not show statistical differences. With two treatments the productive potential of the variety was reached but the drip irrigation presented the best results, producing an additional 3.49 kg of fresh tubers per m3 of water used. [ABSTRACT FROM AUTHOR]

Restudy of an Ordovician diploporite specimen from the Middle Ordovician of central Spain reveals that the species 'Calix' inornatus meléndez has four ambulacra, each with two equal facets, an oval hydropore and a smooth thecal surface. In contrast, the type species of Calix has four ambulacra, each with four facets added in a clockwise direction during growth, a trilobed hydropore, and a theca with spiny plates. Other aristocystitid genera with four ambulacra have one facet per ambulacrum. 'Calix' inornatus differs from all other aristocystitid genera and warrants a new generic name, for which we propose Enodicalix. [ABSTRACT FROM AUTHOR]

The Great Ordovician Biodiversification Event (GOBE) represents a diversification at lower taxonomic levels of most body plans that had appeared during the Cambrian explosion. Among trilobites, several novelties related to enrolment evolved during the GOBE. A kinematic analysis by means of 3D modelling of some new enrolment types shows no relationship with those of the Cambrian trilobites. While some structures emerged for the first time in Ordovician trilobites (e.g. articulations and panderian organs), other structures (e.g. anterior and posterior arch in head and tail) appear earlier in Cambrian trilobites. Our results suggest that the evolution of some groups was clearly rooted in the Cambrian explosion while others clearly appeared during the GOBE. [ABSTRACT FROM AUTHOR]

The Fezouata Lagerstätte, discovered in the Lower Ordovician rocks of Morocco, is a Konservat‐Lagerstätte of prime scientific importance. It provides access not only to the ‘shelly’ (skeletonized) part of its fossil assemblages, but also to non‐biomineralized to lightly sclerotized organisms and to exceptionally preserved soft tissues of a complex ecosystem, mixing elements of both the ‘Cambrian Explosion’ and the ‘Great Ordovician Biodiversification Event’ (GOBE). The Fezouata Lagerstätte occurs at different intervals in the Fezouata Shale, a formation ranging from the lower Tremadocian to the upper Floian (Lower Ordovician). In spite of recent major advances in the detailed biostratigraphy of the Fezouata Shale, there is currently no consensus on the precise age of the fossiliferous levels yielding exceptionally preserved assemblages. Consequently, all available biostratigraphical evidence based on several fossil groups is here critically reviewed and discussed. It can be concluded that exceptional preservation is restricted to a few thin, discontinuous, lens‐shaped horizons occurring in two distinct parts of the Fezouata Shale: a lower interval (260–330 m above the base of the formation) and an upper interval (570–620 m). Integrated biostratigraphical studies, essentially based on investigations of graptolites, acritarchs and conodonts, indicate that the lower interval can be correlated with the upper Tremadocian, whereas the upper interval corresponds to the middle Floian. [ABSTRACT FROM AUTHOR]

Two species of cornulitids, Cornulites gondwanensis sp. nov. and C. aff. shallochensis Reed are described from the Hirnantian of Morocco, within an assemblage representative of the Hirnantia brachiopod fauna occurring near the Ordovician South Pole. The dominance of aggregated and solitary free forms could be explained by particular sedimentary environments preceding the Hirnantian glaciation and the latest Ordovician Extinction Event. The diversity of cornulitids in the Late Ordovician of Gondwana and related terranes was relatively low, and less diverse than the cornulitids of Laurentia and Baltica. Hirnantian cornulitids from Morocco do not resemble Late Ordovician cornulitids of Baltica and Laurentia. Moroccan cornulitids seem to be closely allied to some older Gondwanan cornulitids, especially Sardinian ones. They resemble species described from the Late Ordovician and Llandovery of Scotland suggesting a palaeobiogeographic link. [ABSTRACT FROM AUTHOR]

The Bohemo-Iberian regional scale for South Gondwana, involving the 'Mediterranean Province', comprises five regional stages (Arenigian, Oretanian, Dobrotivian, Berounian and Kralodvorian) plus the global Tremadocian and Hirnantian. The predominance of shallow-water taxa in those high-latitude faunas imposes serious difficulties for correlating the regional succession with the formal global chronostratigraphy because of the almost total absence of the key graptolites and conodonts defining the base of the standard series, stages and stage slices. Instead, the abundant benthic faunas (trilobites, brachiopods, molluscs, echinoderms) of South Gondwanan origin largely dominated in the area from the middle Darriwilian to the late Katian. The poleward faunal migration of originally Avalonian, Baltic, Laurentian and even Asiatic taxa during the Boda Event of global warming progressively ends with the endemicity in the region, where the ensuing benthic assemblages were severely affected by the Hirnantian glaciation. The regional scale significantly improves the precision of correlations between Ordovician strata from SW and central Europe, North Africa and a large part of the Middle East. An updated record of palaeontological data from areas where Mediterranean faunas remain practically unknown, or are still poorly investigated, is also included. Palaeobiogeographical relationships based on the distribution of faunas across South Gondwana are suggested as an improvement for positioning many territories in modern palaeogeographical reconstructions and offer a constructive approach to problems related to the pre-Variscan and pre-Alpine orogenic puzzles. [ABSTRACT FROM AUTHOR]

Pterotheca hispanica nov. sp. is described from the basal beds ( Stimulograptus sedgwickii graptolite Zone) of the Formigoso Fm., in the Cantabrian Zone of the Iberian Massif, north-western Spain. This specialized bellerophontoid gastropod is for the first time recorded in the Silurian of peri-Gondwana; it is the only Aeronian species known so far. Its most closely allied relatives are from higher beds placed in the Telychian of Scotland. Pterotheca is considered a highly derived genus within the Pterothecinae of the Carinaropsidae, with the strongly reduced to absent coiling and the growth of the septum being synapomorphies. In the present work it is shown that not only the apical angle of the septum can be used to distinguish species, but also the relative length and width of the septum. In some cases, the slit may extend as far back as the anterior part of the internal septum. Silurian species were hitherto only found in marginal Laurentian and Eastern Avalonian settings. Pterotheca is absent from central Laurentia and Baltica, where it could be expected to be present based on its wide Ordovician distribution. In the light of this, the occurrence of the genus in the Aeronian of Spain seems difficult to explain, albeit the genus was present in peri-Gondwana prior to the end-Ordovician extinction. The extreme scarcity of described taxa recorded from Avalonia, Baltica and Iberia during the Early Silurian may explain this patchy distribution. [ABSTRACT FROM AUTHOR]

Object detection and classification have countless applications in human-robot interacting systems. It is a necessary skill for autonomous robots that perform tasks in household scenarios. Despite the great advances in deep learning and computer vision, social robots performing non-trivial tasks usually spend most of their time finding and modeling objects. Working in real scenarios means dealing with constant environment changes and relatively low-quality sensor data due to the distance at which objects are often found. Ambient intelligence systems equipped with different sensors can also benefit from the ability to find objects, enabling them to inform humans about their location. For these applications to succeed, systems need to detect the objects that may potentially contain other objects, working with relatively low-resolution sensor data. A passive learning architecture for sensors has been designed in order to take advantage of multimodal information, obtained using an RGB-D camera and trained semantic language models. The main contribution of the architecture lies in the improvement of the performance of the sensor under conditions of low resolution and high light variations using a combination of image labeling and word semantics. The tests performed on each of the stages of the architecture compare this solution with current research labeling techniques for the application of an autonomous social robot working in an apartment. The results obtained demonstrate that the proposed sensor architecture outperforms state-of-the-art approaches. [ABSTRACT FROM AUTHOR]

Lower–Middle Ordovician brachiopods are well known from the Central Andean Basin of Argentina and Bolivia, but relatively little data comes from its northern prolongation in the Altiplano and the Eastern Cordillera of Peru. Here we present information about brachiopods collected from the San José Formation (Fm) from several sections located at the northeast of the Apurímac River valley in the surroundings of Kimbiri city in the Eastern Cordillera. From northwest to southeast the sections and their locations are: Libertad, in the mountain trail between this hamlet and the city of Pichari; Catarata and Nueva Alianza, in the mountain trail between Oroya and the last hamlet; and Kimbiri (K), in the trail parallel to the Kashiroveni stream north of the village of Kimbiri Alto. In these localities the San José Fm lies unconformably on Neoproterozoic rocks, reaching the maximum thickness of about 700 m. This shale-dominated formation comprises a biostratigraphically almost complete succession of the upper Tremadocian to lower Sandbian strata and contains graptolites, trilobites, brachiopods, molluscs, echinoderms and ostracods, as well as some conodonts and other microfossils. The upper part of the San José Fm is unconformably overlain by a thick sandy and diamictic succession, known as the Kimbiri Fm. About 30 fossiliferous levels have been found in the San José Fm in the Kimbiri section, nine of which contain identifiable brachiopod remains and most of them are precisely constrained by graptolites. The lowermost brachiopod-bearing fossiliferous bed (K-03) occurs about 115 m above the base of the section, being assigned to the Baltograptus minutus Graptolite Biozone (GB) (upper Floian, Fl3) and containing a single specimen of a small indeterminate orthid. Stratigraphically higher in the formation, the next two assemblages in the beds K-07 and K-11, containing also upper Floian graptolites, provided Paralenorthis immitatrix. This species was originally described from the San Lucas locality of the Bolivian Eastern Cordillera, from rocks tentatively correlated with the upper Floian–lower Darriwilian. It also occurs in the San José Fm in the Inambari River section located in the Peruvian Eastern Cordillera, ca. 250 km to the east of Kimbiri, in the interval corresponding to the upper Floian–Dapingian(?). Sandstones occurring about 40 m higher, in the fossiliferous bed K-12, yielded a slightly more diverse assemblage composed of Mollesella planidorsalis, P. immitatrix and an indeterminate orthoid. M. planidorsalis is characteristic of the Loma del Kilómetro Member of the Suri Fm in the central Famatina Range, correlated with the Floian to middle(?) Dapingian based on the occurrence of conodonts of the Prioniodus elegans, Oepikodus evae and Baltoniodus navis conodont biozones. Less than 10 m higher, the sandstones of the bed K-13 only yielded two poorly preserved unidentifiable specimens of Ahtiella. Slightly higher, in the bed K-15 just below the Holmograptus lentus or Didymograptus artus GB, a more diverse assemblage is dominated by a new species of Phragmorthis as well as by P. immitatrix; additionally it contains few specimens of Ahtiella zarelae and a new species of Dalmanella. A. zarelae was exclusively reported from the San José Fm at the Inambari River section. From this level upwards, the brachiopod assemblages become homogeneous in the Kimbiri section (but dominance changes) and co-occur with graptolites of the Didymograptus artus GB (middle Darriwilian, Dw2). For instance, in the bed K-16 a new species of Dalmanella becomes predominant. The bed K-17 yielded only P. immitatrix. The highest sampled bed with brachiopods (K-21) is dominated by A. zarelae and a new Phragmorthis species, P. immitatrix is still present and unidentifiable specimens of Christiania occur. This particular assemblage occurs about 30 m below shales of the Nemagraptus gracilis GB (lower Sandbian, Sa1). The brachiopod occurrences cited above improve the knowledge of the late Early Ordovician–early Middle Ordovician faunas of the Peruvian Eastern Cordillera and emphasize strong connections of this region with the Bolivian Eastern Cordillera and Argentinian Famatina Range during that epoch. Additionally, the occurrence of Phragmorthis suggests connections with several low-latitude terranes and palaeocontinents, such as the Mayo Terrane, Laurentia, Baltica, and South China [ABSTRACT FROM AUTHOR]

Background: The information regarding the factors that affect the success of extubation in neurosurgical patients is limited; thus, it is necessary to determine the prevalence, and the associated factors, of extubation failure in neurosurgical patients. Methods: It was performed a prospective, longitudinal, observational and comparative study in neurosurgical patients with criteria for extubation. In those who the number of endotracheal aspirations had failed 24 hours before extubation, it was analyzed the presence of cough reflex, length of stay and mechanical ventilation days. Results: 70 patients were included in the study, of whom 11.4 % patients failed extubation and the associated factors were performing 6 events or more of endotracheal tube suction 24 hours prior to weaning (relative risk [RR] = 1.88, 95 % confidence interval [CI] = 1.14-3.09, p 0.01), 7 days of mechanical ventilation (RR = 1.31, 95 % CI = 1.08-1.57, p 0.005) and a length of hospital stay of 7.5 days (RR = 1.24, 95 % CI = 1.05-1.47, p 0.01). Conclusions: performing 6 or more endotracheal tube suction events during the 24 hours before extubation is a risk factor for extubation failure in neurosurgical patients. [ABSTRACT FROM AUTHOR]

The Fezouata Shale (= Fezouata Formation) has produced the most complete Lower Ordovician graptolite succession known from the African continent, which was studied from 32 sections located along the western, central, and eastern Moroccan Anti-Atlas. A composite biostratigraphic and chronostratigraphic scheme is presented for the entire formation that, in ascending order, comprises the Anisograptus matanensis – Rhabdinopora flabelliformis anglica zones (uppermost lower Tremadocian), “ Adelograptus ” tenellus and Aorograptus victoriae zones (middle Tremadocian), Araneograptus murrayi and Hunnegraptus copiosus zones (upper Tremadocian), ? Cymatograptus protobalticus Zone (lower Floian), ? Baltograptus jacksoni Zone (middle Floian), and the Baltograptus minutus Zone plus an “ Azygograptus interval” (upper Floian). Most of these zones or biozones are recorded for the first time in Africa, together with important graptolite species such as Ancoragraptus bulmani (Spjeldnaes), ? Cym. protobalticus (Monsen), ? B. jacksoni Rushton, Clonograptus multiplex (Nicholson), B. minutus (Törnquist) and Azygograptus eivionicus Elles. A correlation with the graptolite sucession from the Algerian Sahara is also suggested, reinforced by the common record of the minute anisograptid Choristograptus louhai Legrand, providing its second world occurrence in the Tremadocian of Morocco. The prior late Tremadocian dating of the Fezouata Lagerstätte is here extended to the middle Floian as revealed by the graptolite biochronology. The repeated record along the lower and middle parts of the Fezouata Formation of deep-water mesopelagic species of the genera Araneograptus — with mass occurrences of conical colonies, together with large horizontal rhabdosomes of Paratemnograptus , Paradelograptus , Clonograptus , “ Tetragraptus ” and Holograptus / Schizograptus do not fit the sedimentological interpretation of deposition of these strata in much shallower inshore to mid-shelf environments. This inconsistency has implications when inferring the living conditions of the Fezouata soft-bodied assemblages. [ABSTRACT FROM AUTHOR]

Precise zircon and monazite ID-TIMS U–Pb dating of three Lower Ordovician altered ash-fall tuff beds (K-bentonites) in the Cantabrian Zone of NW Iberia yielded coeval ages together with an equivalent previously studied sample (477.5 ± 1 (Gutierrez-Alonso et al., 2007)), of 477 ± 1.3 Ma, 477.2 ± 1.1 Ma and 477.3 ± 1 Ma, with a pooled concordia age (all analyses in the four samples) of 477.2 ± 0.74 Ma. A conservative estimation of the volume and mass of the studied K-bentonite beds (using exclusively the CZ data) yields a volume for the preserved deposits of ca. 37.5 km 3 (Volcanic Explosivity Index — VEI = 6, Colossal). When considering other putative equivalent beds in Iberia and neighboring realms (i.e. Armorica, Sardinia) the volume of ejecta associated to this event would make it reach the Supervolcanic–Apocalyptic status (VEI = 8, > 1000 km 3 ). At variance with most known cases of this kind of gigantic eruption events, geological observations indicate that the studied magmatic event was related to continental margin extension and thinning and not to plate convergence. We speculate that a geochronologically equivalent large caldera event recognized in the geological record of NW Iberia could be ground zero of this super-eruption. [ABSTRACT FROM AUTHOR]

The great increase that in the last decades have experienced pragmatic studies has generated a special attention to the so called rhetorical questions. Nevertheless, many times this kind of analysis is founded on artificially created ad hoc examples in such a manner that to a certain extent final results are conditioned by the methods. In this paper we have tried to paliate these deficiencies by improving three basic subjects: 1) we do not start from a previous intuitive prototipical Knowledge of the rhetorical question, on the contrary, we basically look for its limits; 2) we obtain the occurrences from dramatic texts, so every sentence appears in a proper manner with its complete pragmatic-intentional context; 3) as a result of 1 and 2 we can define the most important features of the «rhetorical cycle» implied in this construction and its variations in order to establish the communicative profiles of the rhetorical questions. [ABSTRACT FROM AUTHOR]

Two new species of cornulitids, Cornulites zatoni sp. nov. and Cornulites vilcae sp. nov., are described from the lower part (Sandbian) of the Calapuja Formation of south-western Peru. Late Ordovician cornulitid diversities of Peru (Gondwana) and Estonia (Baltica) are similar. Aggregative growth form dominates among the cornulitids of the Sandbian of Peru. Multiple oriented C. zatoni sp. nov. specimens on a strophomenid brachiopod likely represent a syn vivo encrustation. Cornulitids from the Sandbian of Peru differ from those known from the Sandbian of Baltica. C. zatoni sp. nov. possibly also occurs in the Late Ordovician of Laurentia. [ABSTRACT FROM AUTHOR]

The regional chronostratigraphy of the British Ordovician, established mainly for shelly facies, is hard to correlate in the Iberian Peninsula, especially after the separation and drift of Avalonia from Gondwana by the early Middle Ordovician. The same applies to the Ordovician global scale, whose stratotypes involve deeper-water facies and faunas not recorded in the high-paleolatitudinal settings of southern peri Gondwana. In order to solve the problem, an alternative regional scheme for the "Mediterranean" Ordovician was proposed in the 1970s. This comprises five regional stages plus the global Tremadocian and Hirnantian, which are largely based on the distribution of endemic shelly fossils combined with some graptolites and a good palynological record. This Ordovician scale presents precise correlation potential for southwestern and central Europe (Ibero-Armorica, Sardinia, Bohemia, Bulgaria) andmay be extended around the Mediterranean region. Sporadic occurrences of graptolites and shelly faunas of Baltic or Avalonian affinities allow for indirect correlation with the global stages through their own regional scales. [ABSTRACT FROM AUTHOR]

Illaenid trilobites were relatively scarce in south-polar peri-Gondwanan areas during the Ordovician, with all their African occurrences restricted to the Middle and Upper Ordovician of Morocco. At a specific level, only the Bohemian form Ectillaenus benignensis (Novák) has been positively identified from the Middle Ordovician of that region. In the present work we add the discovery of the new form Caudillaenus nicolasi gen. et sp. nov., occurring in a single bed of late Darriwilian 2 age within the Taddrist Formation of the Rahiat region (south of Alnif), in the central Moroccan Anti-Atlas. The new genus is characterized by a large and subtriangular pygidium, a cephalon with relatively large eyes, a broad rostral plate with a short upwardly and forwardly turned posterior flange, and a globose hypostome. It shows a spheroidal enrolment type previously unknown in illaenids, with the pygidium protruding beyond the cephalon, and the cephalic margin fitting into a shallow and wide coaptative furrow on the pygidial doublure. [ABSTRACT FROM AUTHOR]

The boundaries and subdivisions of the global Dapingian stage cannot be adequately characterized in the extensive south-polar Gondwana continental shelves. Correlatable sediments, dated to some extent by palynomorphs, are generally highly condensed in shale facies ( < 10 m thick) or are entirely lacking, whereas in shallow-water sandstones they may locally reach more than 100 m thick. In the absence of valuable data derived from key macrofossils (graptolites and conodonts), the regional chitinozoan biostratigraphy has gone through numerous conceptual variations in the last 20 years, which has not helped a precise definition of the base of the Dapingian, provisionally included in the “upper” Arenigian regional stage of peri-Gondwana. [ABSTRACT FROM AUTHOR]

This article offers a study of the latin particles enim and nam from a pragmatic- intentional perspective. The results are analysed from two different points of view. In the first one, the four most important topics taken into account are: 1.- enim and nam in interrogative sentences; 2.- enim in expressive contexts; 3.- enim and nam in imperative sentences; 4.- enim and nam + haud. The main conclusion of our study is that both particles are Intentional Discourse Markers; enim shows that the sentence is thought from a subjective attitude, and nam from an objective one. The aim of fourth section is to contrast the statistics of enim and nam in several Latin authors. Figures point out that every writer maintains an objective or subjective attitude towards his discourse according to the nature of the literary gender. Finally, in the last section, we give attention to the relation (‘global ratio’) between the ocurrences of enim and nam and the total number of verses (or lines) in order to stablish the degree of personal implication which an author wants to reveal about his discursive responsibilities. [ABSTRACT FROM AUTHOR]

Paleovalleys and their infilling successions are described from outcrops and drill cores of the Cantabrian Range (northern Spain). A Hirnantia fauna and associated diamictites with striated lonestones indicate that the paleovalleys are related to the Hirnantian (latest Ordovician) glacial event. Based on overall geometry, depositional facies, and associated deformation structures, the paleovalleys are interpreted as subglacial tunnel valleys. They were most likely related to the North Gondwana ice sheet. The ice sheet therefore reached the Ibero-Armorican domain that was still attached to the Gondwana landmass at least until the latest Ordovician. [ABSTRACT FROM AUTHOR]

Large quarrying surfaces of roofing slate in the Arouca Geopark (northern Portugal), formed under oxygen-depleted conditions, have yielded a unique Ordovician fossil lagerstätte that reveals new information on the social behavior of trilobites. It provides several of the world's largest trilobite specimens (some reaching 70 cm), showing evidence of possible polar gigantism in six different species, as well as numerous examples of monotaxic and polytaxic size-segregated autochthonous trilobite clusters, some of which contain as many as 1000 specimens. These reveal a very diverse social behavior, which includes temporary refuge from predation and synchronous molting and reproduction, demonstrated for the first time in five contemporary families of three different trilobite orders from a single formation. [ABSTRACT FROM AUTHOR]

Abstract: Records of UV data started in Madrid at the beginning of the 90''s decade. After some quality control on the data a seven year period from 1996 to 2002 was selected to perform an analysis of daily and seasonal variability of solar ultraviolet B (UVB) values at the centre of the Iberian Peninsula. Instruments used are a Brewer MKIV spectrophotometer and a YES UVB-1 broadband pyranometer. Both instruments provided integrated daily values according with the Diffey spectrum although they have different measurement procedures. Data statistics from each instrument for the same period and statistical relationships between daily values from both instruments are shown. As broadband YES provided a record with fewer time gaps, analysis of UVI extreme values is performed using that instrument. The relationship between UVB values with ozone, cloudiness and visible radiation has been described in several papers for different places in the world. In this paper, those relationships are shown for Madrid. A discussion about specific problems found when trying to isolate every effective factor is also included. Some of those relationships could be helpful to retrieve UVB values from other ancillary data as visible radiation and cloudiness. Finally, a detailed study for 10 days in June 1997 when the maximum record of daily values from the present time series was obtained, highlight the close correlation between total ozone content and the daily variability of UVB for similar amounts of incoming radiation. [Copyright &y& Elsevier]

Middle Ordovician formations of the Anti-Atlas ranges of southern Morocco provided a diverse record of trilobites, molluscs, echinoderms, brachiopods, graptolites and micro- and ichnofossils from about 180 fossil localities. These were mainly found during the national geological mapping to the 1:200.000 scale, and most of them remained unreferenced until now. The lithostratigraphic position of all fossil localities is briefly studied showing, in some cases, noteworthy discrepances with previous works. Besides this stratigraphical reappraisal, a review of the fossil record for each formation and locality is done, together with a taxonomical update. From a chronostratigraphical point of view, the whole sucession constituted by the Tachilla Formation and First Bani Group formations are here referred to the Mediterranean regional scale. The Oretanian-Dobrotivian and Dobrotivian-Berounian boundaries are located respectively in the Bou-Zeroual Formation and at the top of the Izegguirene Formation. The transition between the lower and upper Oretanian is provisionally established in the upper third of the Tachilla Formation, and those between the lower and upper Dobrotivian at the base or in the lower part of the Ouine-Inirne Formation. A general correlation with the global standard and British regional scales is also suggested for the Middle Ordovician of the Moroccan Anti-Atlas. The basal limit of the Upper Ordovician series probably lies within the lower part of the Izegguirene Formation. Paleobiogeographical data confirm the interest of this area as an important diversification center for many Mediterranean faunas that underwent remarkable dispersal in northern Gondwanan shelves. [Copyright &y& Elsevier]

We examine the dynamics of small bodies in orbits similar to that of comet 29P/Schwassmann-Wachmann 1, i.e. near-circular orbits between Jupiter and Saturn. As of late 2019, there are 14 other known bodies in this region that lie in similar orbits. Previous research has shown that this region of the solar system, which in this work we call the "near Centaur region" (NCR), is not stable, suggesting that any bodies found in it would have very short lifetimes. We performed 20 Myr high-precision numerical simulations of the evolution of massless particles, initially located in the Kuiper belt but close to Neptune, with perihelia slightly below 33 au ("Neptune crossers"). Some of these particles quickly migrate inward, passing through the NCR before becoming Jupiter Family Comets. We find that objects in the NCR do indeed generally travel through it very quickly. However, our simulations reveal that resonant behavior in this region is somewhat common and can trap objects for up to 100 Kyr. We summarize the dynamics of 29P and other observed bodies in the region—two of which seem to be clearly exhibiting resonant behavior—and use our simulations to put limits on the reservoir size of the Neptune crossers, which at its time determines the reservoir size of the Kuiper belt. Finally, we put some constraints on the current population of Centaurs and particularly of the NCR population, based on the injection rates required to keep the observed population of Jupiter family comets in steady-state. • The dynamics of Near Centaurs (29P-like, i.e. orbits between Jupiter and Saturn) is analyzed and characterized. • Three body resonances provide unexpected stability in the Jupiter-Saturn region. • The Real JFC population was used to constrain the size of Centaur and Kuiper belt populations. • Two real objects between Jupiter and Saturn were found to be exhibiting resonant behavior in our simulations. [ABSTRACT FROM AUTHOR]

In various automated industrial, medical, or service applications using robotic systems it is required to regulate both robot movement and contact force. In order to address this control problem, this paper presents a force/position control structure that has two characteristics that are very relevant in robot-environment interaction tasks. First, the structure of the controller is based on the use of generalized saturation functions, and this makes it possible to ensure that the robot actuators operate within a safe region without exceeding their torque limits. On the other hand, an adaptable term is included within the structure that allows to compensate for parametric uncertainty related to gravitational forces and the stiffness of the environment on which the robot operates. The validity and correct performance of the proposed control structure is based on a rigorous stability analysis, as well as numerical simulations using a three-degree-of-freedom robot manipulator. [ABSTRACT FROM AUTHOR]

A reprint of article "The Bohemo-Iberian regional chronostratigraphical scale for the Ordovician System and palaeontological correlations within South Gondwana" published in journal ins presented. The article outlines faunas found in Mediterranean Province such as trilobites, brachiopods, and molluscs; palaeobiogeographical relationships based on the distribution of faunas across South Gondwana; and Ordovician system discovered by Charles Lapworth.

Trilobites were one of the most successful groups of marine arthropods during the Palaeozoic era, yet their soft-part anatomy is only known from a few exceptionally-preserved specimens found in a handful of localities from the Cambrian to the Devonian. This is because, even if the sclerotized appendages were not destroyed during early taphonomic stages, they are often overprinted by the three-dimensional, mineralised exoskeleton. Inferences about the ventral anatomy and behavioural activities of trilobites can also be derived from the ichnological record, which suggests that most Cruziana and Rusophycus trace fossils were possibly produced by the actions of trilobites. Three specimens of the asaphid trilobite Megistaspis (Ekeraspis) hammondi, have been discovered in the Lower Ordovician Fezouata Konservat-Lagerstätte of southern Morocco, preserving appendages and digestive tract. The digestive structures include a crop with digestive caeca, while the appendages display exopodal setae and slight heteropody (cephalic endopods larger and more spinose than thoracic and pygidial ones). The combination of these digestive structures and the heteropody has never been described together among trilobites, and the latter could assist in the understanding of the production of certain comb-like traces of the Cruziana rugosa group, which are extraordinarily abundant on the shallow marine shelves around Gondwana. [ABSTRACT FROM AUTHOR]

An Ordovician–Silurian boundary section marked by an uninterrupted, relatively high rate of black shale sedimentation and abundant, diverse graptolites is described from the south-central Pyrenees. The structurally simple Estana section comprises the uppermost part of the quartzite-dominated Bar Formation and overlying black shales of late Hirnantian and early Rhuddanian age, which have been dated by graptolites to the upper Metabolograptus persculptus and lower–middle Akidograptus ascensus–Parakidograptus acuminatus biozones. Due to the absence of M. persculptus , a Metabolograptus parvulus Biozone correlative with the upper part of the persculptus Biozone is recognized below the lowest occurrence of akidograptids, which indicate the base of the Silurian System. The graptolite fauna comprise 27 species including Normalograptus minor , N. lubricus , N. rhizinus , Hirsutograptus , Korenograptus bifurcus , K. bicaudatus, K. lanpherei and Nd. shanchongensis , most of which were formerly considered to be endemic to the low-latitude palaeobiogeographical province of China, Siberia and northern North America. Two new species, N. baridaensis and N. ednae , are described. The succession of graptolite assemblages in the Estana section, and occurrence of several cosmopolitan taxa in its parvulus and lower ascensus – acuminatus biozones that are unknown elsewhere in peri-Gondwanan Europe, suggest that strata immediately surrounding the Ordovician–Silurian boundary may be absent, highly condensed or oxic and barren of graptolites in other sections of northwestern peri-Gondwana. Common graptolite synrhabdosomes and abnormal rhabdosomes may indicate some environmental stress in the parvulus Biozone, although the rather uniform black shale lithology, total organic carbon content and δ 13Corg values suggest uninterrupted sedimentation under stable, anoxic conditions. [ABSTRACT FROM AUTHOR]

The objective of this research is to evaluate the occupational risk due to thermal stress on workers in the incineration and drying processes at Arboriente S.A. The research characteristics consist of a field study, which is descriptive and quantitative. The population included twenty workers who perform the stated processes. For risk assessment, the Wet Bulb Globe Temperature Index (WBGT) was used. It is based on the characterization of the workstations, the measurement of the temperatures of Wet bulb, dry bulb and globe. In addition, the determination of the metabolic thermal load, and the calculation and evaluation of the index are also included. As a result, no hygienic risk was evidenced on any of the evaluated workstations attributable to thermal stress. This is mainly due to sufficient acclimatization of the workers and their low metabolic thermal load. [ABSTRACT FROM AUTHOR]

Brachiopods are among the first animal phyla to emerge from the Cambrian Explosion, rapidly diversifying to all major palaeocontinental blocks within 20 million years. The group underwent another steep rise in diversity during the Ordovician, and their relative abundance and diversity made them one of the most successful invertebrate groups during the entire Palaeozoic. During this time, brachiopods lived in a range of environments and represented a significant component of marine ecosystems, yet information regarding their modes of life and ecology is somewhat limited. Recent studies, primarily from the Chengjiang and Burgess Shale Lagerstätten, have revealed that by the Middle Cambrian (Series 3, Stage 5) brachiopods from across the phylum had already developed a range of ecological strategies and life modes. Cambrian brachiopods occupied distinct trophic niches on soft and hard substrates and exhibited at least five types of lifestyles: pedicle attachment, pedicle anchoring, cemented, free‐lying and semi‐infaunal. Comparisons with Ordovician benthic assemblages show that despite the explosion of brachiopod taxa witnessed in the Ordovician, with the exception of the appearance of burrowing brachiopods, life strategies of brachiopods remained largely the same. Indicating that the majority of life modes observed in brachiopods had rapidly evolved and was already in place prior to the Great Ordovician Biodiversity Event. [ABSTRACT FROM AUTHOR]