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The first report of the Hirnantia high-latitude peri-Gondwanan Fauna from Portugal (Upper Ordovician, Ribeira do Braçal Formation) is presented here. The described macroassemblages are fairly diverse containing fossils of brachiopods, trilobites, echinoderms, machaeridians, and ostracodes. Among the brachiopods, the most abundant is Mirorthis mira. Plectothyrella cf. P. libyca, Paromalomena cf. P. polonica, Plectoglossa? sp., and a small indeterminate discinoid are also present. The trilobites are represented by abundant sclerites of Mucronaspis cf. M. mucronata, and an isolated cranidium and pygidium assigned to Flexicalymene. The occurrence of Mucronaspis and Flexicalymene represents the first record of these genera in Portugal. Echinoderms are dominant in the basal bed of the formation; the columnal plates tentatively ascribed to morphogenus Pentagonocyclicus are the most abundant, followed by the echinosphaeritids. Abundant disarticulated machaeridian plates, of the genus Plumulites, associated with trilobites are present in one of the localities. Ostracodes were found in one single locality and have been assigned tentatively to the genus Herrigia. Ramose and massive bryozoans also occur in the assemblage. This new macrofossil assemblage supports the assignment of an Hirnantian age for the Ribeira do Braçal Formation. Most of the brachiopod species and the dalmanitid Mucronaspis are commonly present in Hirnantian deposits globally, but the presence in the assemblage of a brachiopod close to Plectothyrella libyca, a cold-water species, previously reported only from the Hirnantian of Libya and Morocco, is noticeable. This strengthens the case for a high latitudinal setting of the present-day territory of the Portuguese Central Iberian Zone during the Late Ordovician.
Using the positive degree days approach and ERA-Interim reanalysis downscaled data, the researchers ran a melt model spatially gridded at 200 m with annual temporal resolution over 32 years and estimated surface melt (SM) and surface runoff (SR) on the Antarctic Peninsula. The model was calibrated and validated independently by field measurements. The maximum surface melt values occurred in 1985 (129 Gt), and the maximum runoff (40 Gt) occurred in 1993; both parameters showed minimum values in 2014 (26 Gt and 0.37 Gt, respectively). No significant trends are present. Two widespread positive anomalies occurred in 1993 and 2006. The results reveal that the floating ice areas produce an average of 68% of runoff and 61% of surface melt, emphasizing their importance to coastal hydrography. During the seven years preceding the Larsen B collapse, surface melt retention was higher than 95% on floating ice areas, and negative runoff anomalies persisted. Excluding the islands, the vicinity of this former ice shelf exhibits the highest specific surface melt and runoff across the studied area.
In this review, we explore the state-of-the-art of sand fly relationships with microbiota, viruses and Leishmania, with particular emphasis on the vector immune responses. Insect-borne diseases are a major public health problem in the world. Phlebotomine sand flies are proven vectors of several aetiological agents including viruses, bacteria and the trypanosomatid Leishmania, which are responsible for diseases such as viral encephalitis, bartonellosis and leishmaniasis, respectively. All metazoans in nature coexist intimately with a community of commensal microorganisms known as microbiota. The microbiota has a fundamental role in the induction, maturation and function of the host immune system, which can modulate host protection from pathogens and infectious diseases. We briefly review viruses of public health importance present in sand flies and revisit studies done on bacterial and fungal gut contents of these vectors. We bring this information into the context of sand fly development and immune responses. We highlight the immunity mechanisms that the insect utilizes to survive the potential threats involved in these interactions and discuss the recently discovered complex interactions among microbiota, sand fly, Leishmania and virus. Additionally, some of the alternative control strategies that could benefit from the current knowledge are considered.
This study assessed the anthelmintic activity of plant-derived compounds against gastrointestinal nematodes of goats using the egg hatch and larval motility assays. The compounds tested were saponins (digitonin and aescin) and their respective sapogenins (aglycones), hecogenin acetate and flavonoids (catechin, hesperidin, isocordoin and a mixture of isocordoin and cordoin). Additionally, cytotoxicity of active substances was analysed on Vero cell through 3-4,5-dimethylthiazol-2-yl,2,5diphenyltetrazolium bromide (MTT) and propidium iodide (PI) tests. Significant reduction on the egg hatching (P < 0.05) was seen only in the treatments with aescin (99%/EC50 = 0.67 mg mL−1) and digitonin (45%). The compounds that reduced the larval motility (P < 0.05) were digitonin (EC50 = 0.03 mg mL−1 and EC90 = 0.49 mg mL−1) and the hecogenin acetate (75%). The other sapogenins showed low anthelmintic activity. All the flavonoids showed low ovicidal (4–12%) and larvicidal (10–19%) effects. The aescin and digitonin showed low toxicity in PI test (viable cells >90%). Nevertheless, higher cytotoxicity was observed in the MTT assay, with IC50 of 0.20 mg mL−1 (aescin) and 0.0074 mg mL−1 (digitonin). Aescin and digitonin have a pronounced in vitro anthelmintic effect and the glycone portion of these saponins plays an important role in this activity.
We performed a systematic review and meta-analysis on the prevalence and factors associated with Schistosoma mansoni infection in Brazil. We searched the PubMed, Web of Science and Latin-American and Caribbean System on Health Sciences Information (LILACS) databases, scientific publications articles, according to The PRISMA Statement, from 2000 to 2016. A total of 27 studies were included according to the established criteria. The prevalence of S. mansoni infection varied widely, from 0·1 to 73·1%, based on Kato-Katz technique. Of the identified studies, 42·9% were performed in the state of Minas Gerais, and 33·3% were performed in the northeast region of Brazil. We identified sex, age, education level, family income, contact with water and the presence of the intermediate host snail as major risk factors associated with infection. The meta-analysis summarized a high prevalence rate pooled for Schistosoma mansoni. On the other hand, the analysis of the subgroup showed a highly significant reduction of the prevalence rate after control measures. The epidemiological factors evidenced in the studies show the influence of environmental and social conditions on the occurrence of schistosomiasis.
The pitting corrosion resistance of AL-6XN PLUS™ superaustenitic stainless steel, 304L, 316L, and 317L austenitic stainless steels was investigated using the cyclic polarization technique. These materials were evaluated in the as received condition and heat-treated at temperatures between 500 °C and 900 °C for 72 h. A thermodynamic simulation was performed using the software Thermocalc® to predict possible deleterious phases in selected temperatures. The simulations have predicted the sigma phase in the selected temperature range. An aqueous solution of sulfuric acid and sodium chloride was used as electrolyte in the corrosion tests. The results showed that pitting corrosion was not observed on the samples of AL-6XN PLUS™ steel. The 304L steel suffered pitting corrosion. All the polarization curves of this steel showed hysteresis characteristics of pitting corrosion. The 316L and 317L steels were resistant to pitting corrosion, but susceptible to crevice corrosion.
Plant facilitation can improve the diversity of plant communities in several ecosystems, especially in stressful environments. The establishment of tree species on rocky outcrops can be limited by several biotic and abiotic factors. The richness and abundance of forest trees species on rocky outcrops surrounded by a large forest remnant in south Brazil were correlated with the cover of Bromelia balansae, a spiny stoloniferous species commonly occurring at forest–grassland transitions. Sixty plots were established on three flat rocky outcrops (20 in each). In each plot the coverage of bromeliads was estimated into three classes (0%, 1–50% and 51–100%) and all seedlings (individuals 10–30 cm in height) were counted and identified. ANOVAs with randomization tests were performed to establish the effect of different bromeliad cover classes on the richness and abundance of seedlings. The cover of bromeliads was positively related to the richness and abundance of young pioneer tree species. Evidence suggests that B. balansae can act as a nurse plant for tree seedlings, but manipulative experiments are needed to confirm this.
Government support uncertainty, scarce yield information, and the inherent risk in bioeconomic phenomena are some of the deterrents faced by investors in the nascent cellulosic biofuel industry. A financial probabilistic model was developed to contrast the economic feasibility of producing cellulosic biofuels from energy cane and sweet sorghum using three technologies: hydrolysis, pyrolysis, and gasification. Hydrolysis and pyrolysis proved feasible (showed possibilities of a positive net present value) without government support and conditioned to stochastic feedstock yields and biofuel prices. Gasification was feasible with government support. Improved feedstock and biofuel productivity would considerably raise the feasibility probabilities for hydrolysis and pyrolysis without government support.
Two distinct Pleistocene assemblages from SE Santiago Island are comparable to modern analogues elsewhere in the Cape Verde Islands. A low-diversity Siderastrea radians assemblage lived atop basalt knobs surrounded by sand on a slope below a cliff. A Millepora alcicornis–Megabalanus azoricus assemblage occupied the cliff. The latter was a typical rocky-shore assemblage from a high-energy setting below the tidal zone. Bioerosion structures in basalt produced by Circolites kotoncensis and Gastrochaenolites isp. also occur there. Despite extensive studies on local limestone deposits in 1832 and 1836, lack of exposure prevented Darwin from seeing these fossils.
In this paper, we present the first laboratory experiments that show the generation of internal solitary waves by the impingement of a quasi-two-dimensional internal wave beam on a pycnocline. These experiments were inspired by observations of internal solitary waves in the deep ocean from synthetic aperture radar (SAR) imagery, where this so-called mechanism of ‘local generation’ was argued to be at work, here in the form of internal tidal beams hitting the thermocline. Nonlinear processes involved here are found to be of two kinds. First, we observe the generation of a mean flow and higher harmonics at the location where the principal beam reflects from the surface and pycnocline; their characteristics are examined using particle image velocimetry (PIV) measurements. Second, we observe internal solitary waves that appear in the pycnocline, detected with ultrasonic probes; they are further characterized by a bulge in the frequency spectrum, distinct from the higher harmonics. Finally, the relevance of our results for understanding ocean observations is discussed.
It is widely assumed that there is a natural, prelinguistic conceptual domain of time whose linguistic organization is universally structured via metaphoric mapping from the lexicon and grammar of space and motion. We challenge this assumption on the basis of our research on the Amondawa (Tupi Kawahib) language and culture of Amazonia. Using both observational data and structured field linguistic tasks, we show that linguistic space-time mapping at the constructional level is not a feature of the Amondawa language, and is not employed by Amondawa speakers (when speaking Amondawa). Amondawa does not recruit its extensive inventory of terms and constructions for spatial motion and location to express temporal relations. Amondawa also lacks a numerically based calendric system. To account for these data, and in opposition to a Universal Space-Time Mapping Hypothesis, we propose a Mediated Mapping Hypothesis, which accords causal importance to the numerical and artefact-based construction of time-based (as opposed to event-based) time interval systems.
The feasibility of integrating ethanol production into an existing sugar mill was analyzed by a stochastic spreadsheet model. As the price of corn continues to rise, ethanol producers will eventually need to look at other feedstock alternatives. Sugarcane has been proven to work well in the production of ethanol in Brazil. The results indicated existing U.S. sugar mills could economically switch to ethanol production. As imports into the United States threaten to undermine the U.S. sugar program, sugarcane producers have a viable alternative. At the very least, the alternative exists to diversify their income streams with ethanol production.
This study investigates the possible effects of pre-term births and low birth weight on infant mortality rates (IMRs) over a 15-year period in Ribeirão Preto, Brazil, based on surveys carried out in 1978/79 and 1994. The 1978/79 survey included 6750 births over a 12-month period and the 1994 survey 2846 births over a 4-month period. Infant deaths were retrieved monthly from the city register. Infant mortality rate decreased from 36·6 to 16·9 deaths per 1000 over 15 years. The decrease in IMR was larger in the 2500–2999 g group than in any other group. The observed falls in IMR were attributable to decreases in birth-weight-specific mortality rates. Likewise, there was a general decrease in IMR in mild, moderate and severe pre-term births. The incidence rate ratio of infant mortality between surveys was 0·46 (95% CI 0·34–0·63); it increased to 0·57 (95% CI 0·35–0·75) when adjusted for birth weight and other factors in the model and rose to 0·69 (95% CI 0·49–0·97) when adjusted for length of gestation and other variables. The increase in pre-term births and low birth weight may have had, at most, a marginal effect on the IMR. Progress in the care of newborns may have decreased the mortality risk, but even mild pre-term birth still has an impact on infant mortality. There is room for further improvement in IMR by tackling the high rates of pre-term birth.
War – and its implications for the expenditure side of the government budget – has always been associated with taxes. During most of the Portuguese monarchy, taxes included gold and other domain revenues coming from monopolies established on domestic and international trade. Together with silver and copper, gold was used as money, making its interaction with war and taxes central to the long-term pattern of economic growth and development.
The overview of Portuguese fiscal and monetary institutions from the seventeenth to the nineteenth centuries presented in this chapter is subtitled “The Inheritance of the Real” (plural réis), after the name of the national currency from 1435 until 1911. To the extent that currency experience is embedded in the overall evolution of fiscal and monetary systems, the legacy becomes a case study in institutional persistence and adjustment. In fact, the interaction of war, taxes, and gold implies a mix of fiscal, monetary, and exchange rate policies.
Beginning in the sixteenth century, increasingly expensive warfare became a source of pressure for fiscal change. Times of war were also an auspicious context for the social legitimization of direct and indirect taxation capable of supplementing or replacing domain revenues. This legitimization linked taxation to private property rights in an almost “contractual” manner via the traditional representation of nobility, clergy, and towns in the Cortes. The custom that any new tax should be discussed there reinforced the financial freedom derived from the availability of a stable and convertible currency.
We report on a male infant with pyridoxine dependency and seizures from birth, controlled with pharmacological doses of pyridoxine at 4 months of age. Seizures stopped between 30 and 80 days of age when very-low doses of pyridoxine were given in a multivitamin supplement . Daily dose was 0.5mg that corresponded to 0.08 to 0.16 mg/kg/day when weight gain is considered. In previous reports doses have ranged from 0.2 to 30 mg/kg/day. Another distinctive feature was that this infant went into a coma and developed hypotonia and irregular breathing when pyridoxine was given by enteral tube which has usually been reported when the vitamin is given intravenously. Use of low doses of pyridoxine in multivitamin supplements could be a confounding factor for early diagnosis and appropriate treatment of pyridoxine-dependent seizures.
The spionid polychaete Polydora sp. can live and reproduce inside the oysters' shell, excavating a U-shaped burrow the central portion of which is filled with detritus and particles of dissolved shell. The oyster responds by secreting an organic layer, confining the worm, and later covering it with calcitostracum. This process creates a characteristic "mud blister". Crassostrea gigas were analysed for the organic matrix amino acid content and 14 metals of the whole shell of normal oysters and severely Polydora infested ones. Amino acid, DOPA and FT-Raman analyses were also performed on isolated membranes from the characteristic mud blister and on prismatic layer insoluble matrix (PLIM) of infested oysters, with the aim of detecting any differences between the two organic matrices. Membranes and PLIM composition differ from whole normal shell organic matrix by having lower aspartate and glycine and higher levels of virtually all hydrophobic amino acids, especially alanine. There are no significant differences between membranes and PLIM in the ratio of charged to non-polar amino acids, respectively 0.54 and 0.59. L-DOPA content is also similar in the two matrices with 0.45 (± 0.18) and 0.57 (± 0.30) ng.mg−1 protein for PLIM and membranes respectively. The FT-Raman spectra of membranes is very similar to that of PLIM, suggesting that they have identical composition. Zinc, iron and manganese are significantly higher in infested than in normal shells. Infested oysters can provide an excellent opportunity for investigating normal biological calcification processes.
A new genus and species of Unionoidea, Tacuaremboia caorsii, are described from the Tacuarembó Formation (Upper Triassic–Upper Jurassic) of Uruguay. The genus is distinguished from other Unionoidea by its large size, thickness, edentulous hingeline, and the presence of claustra. It has some similarities with the Anodontinae and the Archanodontacea, but it cannot be assigned to any of the known family units.
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