Long-distance dispersal in amphibians

Although the distribution patterns of major amphibian lineages are mainly explained by a Pangean origin with subsequent vicariant diversification, dispersal events have exerted a strong influence on present-day distributions. Long-distance dispersal (LDD) involves movements outside the standard geographic limits and outside the genetic neighbourhood area of individuals. Although considered ‘rare’, LDD is disproportionately important to amphibian populations, species and communities. To understand the role of LDD in shaping current biogeographic patterns in these tetrapods, we reviewed the cases reported in the literature. A systematic bibliographic search was performed to obtain information on how many studies have dealt with LDD in amphibians, which methods they used, which taxa and distances were involved, and when/where events had apparently occurred. In 41 studies, we recovered at least 90 LDD events (3 active, 87 passive) involving at least 56 extant species and 38 genera. Most events (73) involved the colonization of islands, with rafting being suggested as the most conceivable means of overwater passive dispersal for these vertebrates. In this review, we show that LDD events have played an important role in shaping current amphibian biogeographic patterns, especially the occurrence of disjunct distributions and the colonization of islands

Modelling Weirs in Two-Dimensional Shallow Water Models

Datos experimentais dispoñibles en: http://doi.org/10.5281/zenodo.5062775[Abstract] 2D models based on the shallow water equations are widely used in river hydraulics. However, these models can present deficiencies in those cases in which their intrinsic hypotheses are not fulfilled. One of these cases is in the presence of weirs. In this work we present an experimental dataset including 194 experiments in nine different weirs. The experimental data are compared to the numerical results obtained with a 2D shallow water model in order to quantify the discrepancies that exist due to the non-fulfillment of the hydrostatic pressure hypotheses. The experimental dataset presented can be used for the validation of other modelling approaches.This study received financial support from the Spanish Ministry of Science, Innovation and Universities (Ministerio de Ciencia Innovacion y Universidades) within the project “VAMONOS: Development of non-hydrostatic models forenvironmental hydraulics. Two-dimensional flow in rivers” (reference CTM2017-85171-C2-2-R).http://doi.org/10.5281/zenodo.506277

TOFtracker: combination of time-of-flight and high-accuracy bidimensional tracking in a single gaseous detector

A 5-gap timing RPC equipped with patterned electrodes coupled to both charge-sensitive and timing circuits yields a time accuracy of 77 ps along with a position accuracy of 38 μm. These results were obtained by calculating the straight-line fit residuals to the positions provided by a 3-layer telescope made out of identical detectors, detecting almost perpendicular cosmic-ray muons. The device may be useful for particle identification by time-of-flight, where simultaneous measurements of trajectory and time are necessary

Mind the gap! A review of Amazonian anurans in GenBank

We studied the knowledge gap in GenBank with regard to the ca. 600 anuran species from Amazonia. The markers 12S, 16S, COI and cytb were examined, on which information was available for about half of all species. Both the number of sample sites and the number of samples per species varied greatly (best studied each in 16S: 4.85 ± 10.37; 11.19 ± 31.20), and merely one fifth of all species had at least 5 sample sites. This suggests that a considerable portion of species is underrepresented in GenBank. Representativeness is especially difficult to assess in widespread species that at the same time could well represent cryptic allopatric species (i.e., with smaller distributions). This is a well-known phenomenon in Amazonian anurans considering that truly widespread species do exist. Moreover, limited sampling may not necessarily be the result of limited representativeness, as numerous species are known to occupy relatively small localised to regional ranges only. Our study furthermore revealed that in a geographic context, major portions of Amazonia have as yet been undersampled. That is, the total of 453 sample sites (most with more than one species sampled) are spatially clustered, often in areas with increased anthropogenic activity. We conclude that there is a large knowledge gap in terms of spatial sampling, resulting in taxonomic deficiencies

Prevalence of Pneumocystosis in Sub-Saharan Africa and Helminth Immune Modulation

Sub-Saharan Africa is the region of the world with the highest prevalence of helminth infections. To protect themselves from the defensive mechanisms of their respective hosts, helminths modulate their immune responses. This modulation has relevant clinical and epidemiological consequences, including the inhibition of inflammatory processes that characterize infection by other microorganisms. Severe Pneumocystis pneumonia is characterized by an intense inflammatory reaction that can lead to death. Acquired immunodeficiency syndrome is the main predisposing factor to the development of pneumocystosis. Although the introduction of highly active antiretroviral therapy has led to a notable decline in the incidence of acquired immunodeficiency syndrome-associated complications, pneumocystosis continues to be an important global health problem. Despite the high incidence of human immunodeficiency virus infection in the sub-Saharan region, the prevalence of Pneumocystis pneumonia there has been lower than expected. Several factors, or combinations thereof, may contribute to this evolution. Here, we hypothesize the possible role of helminth immune modulation as an important issue at play. On the other hand, and looking ahead, we believe that the immune modulation achieved by helminths may be an important factor to consider during the design and evaluation processes of vaccines against Pneumocystis jirovecii to be used in Sub-Saharan Africa. The requirements of a balanced triggering of different types of immune responses for controlling the infection produced by this microorganism, as observed during experiments in animal models, support this final consideration.Institute of Health Carlos III, Spanish Ministry of Science, Innovation and University FIS-PI19/0184

Panorama nacional da industria do ferro e aço

Orientador: Celso Pinto FerrazDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de GeocienciasResumo: o uso do ferro e o aço como material estrutural e industrial é indispensável para a sociedade moderna. Seus substitutos para aplicações específicas, como outros metais, plásticos e cerâmicas, não afetarão seu consumo crescente se a economia mundial crescer e distribuir seu produto. Nos últimos anos a estrutura da indústria mundial de ferro e aço entrou em uma nova etapa de seu desenvolvimento. A indústria brasileira de ferro e aço, também, mudou no mesmo sentido e está muito bem posicionada. Nossas grandes reservas de minério de ferro de alta qualidade e a elevada produtividade de nossa indústria siderúrgica, depois do processo de privatização, são condições excepcionais. Esta dissertação avalia a situação da indústria do ferro e do aço no mundo e no Brasil e examina as oportunidades do Brasil vir a ocupar um papel ainda maior como um importante ator nesta indústria. Seu propósito é realçar o potencial estratégico que esta indústria pode ter para o desenvolvimento nacional caso a ação governamental estimule e facilite um aumento eficiente da capacidade de mineração de ferro e de fabricação de açoAbstrct: The use ofthe iron and the steel as structural and industrial material is indispensable for the modem society. 115 substitutes for specific applications, as other metais, plastics and ceramics, won't affect its growing consumption if the world economy grows and distribute its product. In recent years the structure of the world industry of iron and steel entered in a new stage of development. The Brazilian industry of iron and steel also changed in the same way and are very well positioned. Our large reserves of high quality iron ore and the high productivity of our steel industry, after the privatization process, are exceptional conditions. This dissertation appraises the situation of iron and steel industry in the world and in Brazil and examines the opportunities ofBrazil increases its role as a global player in this industry. Its purpose is to highlight the strategic potential that this industry could have for the national development if the govemment action facilitate and stimulate the industry's research and development efforts and the efficient increase ofiron mining and steel making capacityMestradoAdministração e Politica de Recursos MineraisMestre em Geociência

Autonomous RPCs for a Cosmic Ray ground array

We report on the behaviour of Resistive Plate Chambers (RPC) developed for muon detection in ultra-high energy cosmic ray (UHECR) experiments. The RPCs were developed for the MARTA project and were tested on field conditions. These RPCs cover an area of $1.5 \times 1.2\,{m^2}$ and are instrumented with 64 pickup electrodes providing a segmentation better than $20\,$cm. By shielding the detector units with enough slant mass to absorb the electromagnetic component in the air showers, a clean measurement of the muon content is allowed, a concept to be implemented in a next generation of UHECR experiments. The operation of a ground array detector poses challenging demands, as the RPC must operate remotely under extreme environmental conditions, with limited budgets for power and minimal maintenance. The RPC, DAQ, High Voltage and monitoring systems are enclosed in an aluminium-sealed case, providing a compact and robust unit suited for outdoor environments, which can be easily deployed and connected. The RPCs developed at LIP-Coimbra are able to operate using a very low gas flux, which allows running them for few years with a small gas reservoir. Several prototypes have already been built and tested both in the laboratory and outdoors. We report on the most recent tests done in the field that show that the developed RPCs have operated in a stable way for more than 2 years in field conditions.Comment: To appear in the proceedings of the 35th International Cosmic Ray Conference (ICRC2017), Busan, South Korea. Presented by R. Concei\c{c}\~{a}o. 8 page

Rotary Fatigue Testing Machine to Determine the Fatigue Life of NiTi alloy Wires and Endondontic Files

Endodontic rotary file instruments used to treat root canals in dentistry suffered breakthrough transformations in recent years when stainless steel was replaced by Nickel-Titanium (NiTi). NiTi alloys used in Endodontics possess superelastic properties at body temperature (37C) that bring many advantages on the overall performance of the root-canal treatment. They can follow curved root canals more easily than stainless steel instruments and have been reported to be more effective in the removal of the inflamed pulp tissue and protection of the tooth structure. However, these instruments eventually fracture under cyclic bending loading due to fatigue, without any visible signals of degradation to the practitioner. This problem brought new challenges on how new instruments should be tested, as NiTi alloys are highly non-linear and present a large hysteresis cycle in the Elastic domain. Current existing standards are only available for Stainless Steel testing. Thus, many authors have attempted to design systems that can test NiTi endodontic files under fatigue loads. However, no approach has been universally adopted by the community yet, as in most cases they are based on empirical set ups. Following a more systematic approach, this work presents the results of rotary fatigue tests for several NiTi wires from different manufacturers (MemryTM and EuroflexTM). The tests were done on a versatile fully automatic rotary bending testing machine. The formulation is also presented, where the material strength reduction can be quantified from the determination of the strain and the number of cycles until failure