Microporphyritic and microspherulitic melt grains, Hiawatha crater, Northwest Greenland: Implications for post-impact cooling rates, hydration, and the cratering environment

Sand-sized impactite melt grains hand-picked from a glaciofluvial sample proximal to the Hiawatha impact crater in Northwest Greenland contain new information about the crystallization and cooling history of this impact structure, which is concealed by the Greenland Ice Sheet. Of course, the original locations of the individual sand grains are unknown, but this is offset by the substantial number and wide variety of impactite grains available for study. A detailed investigation of 16 melt grains shows that post-cratering crystallization took place under very variable conditions of strong undercooling with temperatures that dropped rapidly from high above their solidus to far below. A distinct event of near-isochemical hydration at above or ∼250 °C is recorded by intense perlitic fracturing and the growth of closely packed mordenite spherulites only 1−3 μm across in felsic melt grains, which was followed by lower temperature hydrothermal alteration along the pre-existing perlitic fractures. The formation of abundant mordenite microspherulites appears to be very rare or not previously recorded in impactite melts and suggests the rapid infilling of the Hiawatha crater by a hydrous source. The infilling did not occur immediately after the impact as in submarine impacts, but soon thereafter, and before the establishment of a low-temperature hydrothermal alteration system common to the waning stage of cooling in many impact structures. These observations and previous documentation of terrestrial organic matter in the impactites are consistent with an impact into a water-rich terrestrial environment, such as through the Greenland Ice Sheet or into a forested, lacustrine−fluvial region.

Comparative case study of two methods to assess the eruptive potential of selected active regions

Solar eruptive events, like flares and coronal mass ejections, are characterized by the rapid release of energy that can give rise to emission of radiation across the entire electromagnetic spectrum and to an abrupt significant increase in the kinetic energy of particles. These energetic phenomena can have important effects on the space weather conditions and therefore it is necessary to understand their origin, in particular, what is the eruptive potential of an active region (AR). In these case studies, we compare two distinct methods that were used in previous works to investigate the variations of some characteristic physical parameters during the pre-flare states of flaring ARs. These methods consider: i) the magnetic flux evolution and magnetic helicity accumulation, and ii) the fractal and multi-fractal properties of flux concentrations in ARs. Our comparative analysisis based on time series of photospheric data obtained bythe Solar Dynamics Observatory between March 2011 and June 2013. We selected two distinct samples of ARs: one is distinguished by the occurrence of more energetic M- and X-class flare events, that may have a rapid effect on not just the near-Earth space, but also on the terrestrial environment; the second is characterized by no-flares or having just a few C- and B-class flares. We foundthat the two tested methods complement each other in their ability to assess the eruptive potentials of ARs and could be employed to identify ARs prone to flaring activity. Based on the presented case study, we suggest that using a combination of different methods may aid to identify more reliably the eruptive potentials of ARs and help to better understand the pre-flare states.

CATALOGUE OF AQUATIC MITES FROM THE MINHO RIVER (NW IBERIAN PENINSULA)

Acari are a subclass of chelicerate arthropods that includes mites and ticks. The present study focuses on the taxonomic diversity of aquatic mites in the Portuguese territory of the Minho Region. Our aim was to compile all available information and thus generate a list of species linking them to the site where they were recorded. Aquatic species were all those that live exclusively in the marine environment, deep sea, intertidal, freshwater, brackish water or in transitional environments with the terrestrial environment if their lifestyle is associated with the aquatic environment. Since the first records of Portuguese endemic mites by Lunblad in the 1950s several authors have contributed to accurately catalogue, record, and redescribe this vast group in Portugal and Minho consecutively. In our review in this work, we used the Global Biodiversity Information Facility (GBIF) to obtain previous occurrences supplemented by an extensive literature review and the book collection Süßwasserfauna von Mitteleuropa, among others. Additionally, we resorted to active sampling and by-catch sampling in the Portuguese section of the Rio Minho catchment area. The collected organisms represent 12 new records for the Minho River and among them 10 are new records for Portugal, which were deposited in the Natural History Museum of the Iberian Peninsula - NatMIP (“Museu de História Natural da Península Ibérica”), Vila Nova de Cerveira, Portugal.

Microplastics in Landfills: A Comprehensive Review on Occurrence, Characteristics and Pathways to the Aquatic Environment

Microplastics, a multi-dimensional environmental stressor group, capable of transboundary migration, are a threat to the global ecosystem. Transboundary migration of microplastics across all environmental matrices is known to originate from a multitude of sources and acts in conjugation with each other. This inter-dependence of sources calls for a detailed scientific analysis of all the sources that are in play. Waste management facilities have already been established as a significant contributor of microplastics to the aquatic and terrestrial environment. A systematic overview of the scientific literature reveals that the existing body of scientific knowledge is mainly focused on wastewater treatment facilities as a source/pathway of microplastics in the environment. Recently the focus shifted towards solid waste management facilities through landfills. Poor plastic waste management practices made discarded plastics the most dominant component of solid wastes. This review elucidates the occurrence and distribution of microplastics, characteristics of microplastics, including size, shapes, colors, and polymer types, in leachate and refuse of landfills. Furthermore, we discussed the transport mechanisms and pathways used by microplastic present in landfills to migrate to subsurface or groundwater and adjacent aquatic bodies. Last, based on the findings, we summarized the gaps in existing studies and suggested future perspectives to be focused on the future. The abundance of microplastics is attributed to the volume of plastic waste in landfills, management of leachate originating from landfills, application of leachate, and age of landfills. Microplastics abundance and characteristics vary in leachate and refuse. Smaller microplastics are predominant in leachate while larger microplastics are predominant in refuse. Landfills are capable of generating secondary microplastics from fragmentation and degradation. Further studies on microplastics in landfills are necessa

Improving functional and motor capacity through means/resources and methods specific to acvatic activities

Introduction. Exercise programs in the aquatic environment have as their main objective the improvement and maintenance of physical capacity/ capability, these being in continuous development and diversification. Water exercise amplifies the effects of general physical exercise, by allowing a more precise control over the movement of each body segment and of the body as a whole. The aquatic environment offers a number of beneficial effects compared to ones offered by the terrestrial environment. The benefits obtained through the aquatic activities are fundamental and are reflected throughout the entire body including both motor, functional and aesthetic level. Material and method. The objective of this study is represented by the identification of new forms of physical exercise that will increase the motor’s capacity. In order to achieve this goal, several methodological requirements were met, such as: successive engagement of the joints and muscle groups in effort (starting with the neck’s muscles, shoulders, arms, torso and legs, simultaneously with scapular-humeral joints, spine and coxo-femoral joints and legs), the gradually usage of exercises, starting with the most basic and then increasing the complexity of the exercises, the usage of the accessible exercises in the beginning of the training, executed with high amplitude and reduced speed, focusing on the correctness of the execution, the selection and the adequate/ appropriately usage of the initial positions according to the subject’s particularities and the shape/form of the exercise, the optimal control of the effort, achieved through a number of iterations, optimal execution time and breaks, the sets of general physical exercises will consist of sets of 8-12 exercises/reps, the principle of symmetry in the execution of the exercises has to be respected, the continuity of practicing a set of exercises for 6 to 8 consecutive lessons, the recommended work method is fragmented-imitative, efficiently combining the explication with the demonstration, the number of repetitions and the movement’s correction. Results and discussions. Analyzing results obtained after the evaluation, we have noticed significant growth in the functional and motor capacities. Conclusions. The systematization of water activities on objective criteria effectively contributes to their knowledge, while allowing them to be included in the spectrum of recreational, sporting, relaxing or therapeutic activities. Keywords: acvatic activities, physical exercise, evaluations,

Mechanobiological Implications of Cancer Progression in Space

The human body is normally adapted to maintain homeostasis in a terrestrial environment. The novel conditions of a space environment introduce challenges that changes the cellular response to its surroundings. Such an alteration causes physical changes in the extracellular microenvironment, inducing the secretion of cytokines such as interleukin-6 (IL-6) and tumor growth factor-β (TGF-β) from cancer cells to enhance cancer malignancy. Cancer is one of the most prominent cell types to be affected by mechanical cues via active interaction with the tumor microenvironment. However, the mechanism by which cancer cells mechanotransduce in the space environment, as well as the influence of this process on human health, have not been fully elucidated. Due to the growing interest in space biology, this article reviews cancer cell responses to the representative conditions altered in space: microgravity, decompression, and irradiation. Interestingly, cytokine and gene expression that assist in tumor survival, invasive phenotypic transformation, and cancer cell proliferation are upregulated when exposed to both simulated and actual space conditions. The necessity of further research on space mechanobiology such as simulating more complex in vivo experiments or finding other mechanical cues that may be encountered during spaceflight are emphasized.

Fuzzy Based Spatial Risk Evaluation of Plastic Pollution: A Case Study of Anambra State of Nigeria

Natural systems, human health, and artistic sensitivities are all threatened by plastic pollution in most developed and developing countries. Plastic has emerged as a major global threat with rivers serving as sink for transported plastics, emanating from the terrestrial environment as a result of human activities. Anambra State in Nigeria is arguably the business hub of the South-eastern part of Nigeria, with a massive output of plastic wastes daily from individuals, commercial activities and industries. Owing to an inefficient waste management system, plastic leakage into her drainage networks is a critical environmental challenge. The aim of this study is to geospatially model the vulnerability associated with the various plastic leakage factors to the environment. To achieve this aim, data on different thematic variables which include plastic waste density, slope, land-use, drainage density and distance to drainage network of the study area were modelled, Geographic Information Systems (GIS) was used to delineate the variables in order to obtain final risk map for the study area. The result of the study indicates that a total area very high risk is 1840.03 km2, this constitutes about 40.11% of the study area. Local Governments Areas (LGA) located in the southern part of the study area is more susceptible to plastic waste leakage, this could be linked to factors like high dense population and increasing rate of urbanization in the region. It is recommended that waste collection should be frequent, strategic and higher priority should be attached to the high risked area from this study. Anambra State Government also needs to work together with plastic recycling companies, for effective collection of plastic wastes in the areas classified as hotspots in plastic litter accumulation as one of the mitigation measures.

Production and Partial Characterization of α-Amylase Enzyme from Marine Actinomycetes

Amylase producing actinobacteria were isolated and characterized from terrestrial environment. There are a limited number of reports investigating the marine environment; hence, in the present study, four marine enzymes were tested for their amylase production ability. On starch agar plates, the Streptomyces rochei strain showed a higher hydrolytic zone (24 mm) than the other isolates. Growth under optimized culture conditions using Plackett-Burman’s experimental design led to a 1.7, 9.8, 7.7, and 3.12-fold increase for the isolates S. griseorubens, S. rochei, S. parvus, and Streptomyces sp., respectively, in the specific activity measurement. When applying the Box-Behnken design on S. rochei using the most significant parameters (starch, K2HPO4, pH, and temperature), there was a 12.22-fold increase in the specific activity measurement 7.37 U/mg. The α-amylase was partially purified, and its molecular weight was determined using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. α-Amylase was particularly active at pH 6 and 65°C. The purified enzyme was most active at 65°C and pH 6, thermal stability of 70°C for 40 min, and salt concentration of 1 M with Km and Vmax of 6.58 mg/ml and 21.93 μmol/ml/min, respectively. The α-amylase was improved by adding Cu+2, Zn+2, and Fe+2 (152.21%, 207.24%, and 111.89%). Increased production of α-amylase enzyme by S. rochei KR108310 leads to production of significant industrial products.

WATER ACTIVITIES WITH THREE AND FOUR-YEAR-OLD CHILDREN:

Contextualization of the objective: Motor experiences in the liquid or terrestrial environment are part of children's behavior, helping children to master the environment, making them autonomous and self-assured. Objective: To report the experience of six months of intervention with water activities for 21 children, of both sexes, aged between three and four years old in an academy in São Luís. Method: The water activities classes lasted forty minutes, they were held twice a week and the classes had an average of eight to ten children aged three to four years. The class was divided into three moments: setting with the environment and with people, the second moment of displacements with floating material and the third moment there were jumps and dives followed by displacements. After a period of six months of intervention, an observational assessment consisting of eight items, with four sub-items each, was applied. The evaluation was applied during a class and the teachers selected a group of children to make the observations and apply the proposed exercises according to the evaluated item. Results: It was found that all children developed the skills proposed in the assessment items, receiving excellent ratings, with the exception of the item "backstroke legs propulsion" in which seven students, four of which had a good rating, three had a very good result. Final considerations: after six months of intervention, it was noticed that there were positive results in the expansion of learning the contents and refinement of the proposed movements, confirming the hypothesis that, within the proposed period, there were benefits in learning to swim.