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Chemical Resistance of Sustainable Concretes Modified with Waste Powder Containing Epoxy Resin, Calcite and Barite
No full textThe currently designed building materials should be in line with the principles of sustainable development, low-emission economy and circular economy. Guided by these criteria, waste powder containing epoxy resin, calcite and barite was included in the concrete mix. The waste material was used as an additional component of the concrete mix in the amount of 7.5% of the cement mass, without reducing the amount of binder. At the same time, the water/cement ratio was used at a level of 0.44 to 0.56. The obtained concretes were characterized by good workability and fluidity, despite the modifier used. Tests were carried out to assess the resistance of the obtained concretes to the effects of sulphates and chlorides. After 28 days of curing, the concrete samples were immersed in a 5% sodium sulphate solution and a 5% sodium chloride solution. After 48 days of exposure, a decrease in the compressive strength of the concrete samples modified with waste powder was noted in relation to the control concretes. In the case of samples exposed to sulphate salts, the introduction of 7.5% by weight of waste into the concrete composition was associated with a reduction in compressive strength by 8% or 9.9%, respectively, for a higher or lower water/cement ratio. The compressive strength of concrete immersed in sodium chloride solution was reduced by 9.9% for samples containing 7.5% waste at a water/cement ratio of 0.56 and by 5.4% when the water/cement ratio was 0.44. The mass of the samples was also monitored during the test. An increase in the mass of all samples, modified with waste powder and those without the modifier, was noted. The average mass changes for concretes immersed in sodium sulphate solution ranged from 0.16% to 0.31%, and for sodium chloride solution from 0.15% to 0.24% and were dependent on the water-cement ratio and the presence of waste in the concrete mix. The analysis of the durability of concretes showed no harmful effect of the modifier on the microstructure of the cement paste resulting from the action of corrosive reagents. The conducted FTIR, XRD, SEM tests did not confirm the formation of, among others, secondary ettringite, which could cause microstructural damage to the cement paste by generating expansive forces, especially in small pores due to the high crystallization pressure. The proposed method of modifying the composition of concrete is promising and can help reduce the problem related to waste management, but also help reduce greenhouse gas emissions
Social Justice, Senior Mobility, and Sustainable Development in the Transportation Sector
No full textIn light of the United Nations Sustainable Development Goals (SDGs) and the world's aging population, achieving sustainable mobility for older individuals has emerged as a top policy goal. Even while inclusive mobility is a key component of many national and regional initiatives, there is still a continuous disconnect between these lofty goals and the practical capacity to measure and carry them out. By putting out a scientific framework for assessing the sustainability and equality of transportation systems for senior citizens, this research fills this gap. The paradigm, which is based on social justice and economic rationality, uses specific metrics to evaluate the spatial distribution of mobility resources, service accessibility, and infrastructural adequacy. The study illustrates how inclusive transport plans can increase accessibility, lower dependency costs, and promote active aging by drawing on European experiences, such as integrated mobility services in Nordic nations and accessibility-enhancing initiatives in the Netherlands and Germany. The suggested paradigm gives policymakers an evidence-based instrument for coordinating transportation investments with the SDGs' pledge to "leave no one behind" and facilitates rigorous comparisons across regional contexts. This strategy achieves the goal of sustainable development through transportation policy by combining the social, spatial, and economic aspects of mobility fairnes
Assessment of Surface Water Quality Using the Water Quality and IPO Index in Soummam Wadi, Algeria
No full textSurface waters are subject to strong anthropogenic pressures caused by the development and extension of agricultural activities, as well as industrial and domestic activities. However, surface water is exposed to significant pollution as they collect domestic and industrial sewage and irrigation effluents. One of the most important resources in Algeria is the water of valley of Soummam (north-eastern Algeria). This study aims to assess and characterize water quality of Soummam wadi. For this purpose, the water quality parameters pH, the biological oxygen demand (BOD5), chemical oxygen demand (COD), nitrites (NO2- ), nitrates (NO3-), orthophosphate (PO43-), dissolved oxygen (O2%), and ammonium (NH4+) concentrations were included to assess the pollution status of the water. A number of water quality index are being used for assessing water quality and evaluated state of organic pollution in surface water in Soummam wadi including: organic pollution index (IPO), surface Water Quality Index according to Demmak.A, 2014, and nitrates (NO3) toxicity following classification of Isaac et al 2009 were also determined. The results achieved in this study show that all sattions indicate a moderate degree of pollution based on IPO index. According to the results obtained by index quality of water, and the classification of Isaac, they looked both similar and complemented the majority of stations have high concentration of BOD5, DCO,and NO3 , showed the poor and very poor surface water quality
Climate-driven invasion risk and ecological niche overlap between non-native round goby and native European fishes
No full textBiological invasions and climate change are two of the most prominent drivers of freshwater biodiversity loss. In this study, we assessed the climate-driven invasion risk and ecological niche overlap between the non-native round goby Neogobius melanostomus and several native European freshwater fishes (Barbatula barbatula, Cottus gobio, Cottus perifretum, Cobitis taenia, Gobio gobio, Gymnocephalus cernua, and Perca fluviatilis) to forecast shifts in their potential distributions using ecological niche modeling combined with future climate projections. Our models projected a substantial northward and westward expansion of N. melanostomus under future climate scenarios, with suitable habitats increasing especially under high-emission pathways. Native species also exhibited shifts in their distributions, often resulting in increased geographic overlap with N. melanostomus. Habitat overlap was most pronounced between N. melanostomus and C. taenia, with future projections identifying over 10% of the landscape as high-suitability. Overlap hotspots were concentrated in northern Europe, particularly along the coasts of the Netherlands, Germany and the UK, highlighting the potential for escalating biotic interactions such as competition, habitat displacement, and trophic disruption, particularly in vulnerable benthic communities. Alongside negative interactions, our results highlight potential climate refugia with limited projected overlap, pointing to priority areas for conservation. Our findings thus emphasize the urgent need for regionally targeted monitoring and conservation strategies that account for both climate-driven range dynamics and ecological interactions between invasive and native species. Integrating spatial forecasting with ecological risk assessment offers critical insights that can support efforts to mitigate the impacts of biological invasions in a warming world
An extraordinary colonial spider community in Sulfur Cave (Albania/Greece) sustained by chemoautotrophy
No full textWe report the discovery and detailed analysis of an extraordinary colonial spider assemblage in Sulfur Cave, a chemoautotrophic sulfidic ecosystem located on the Albania-Greece border. The colony, comprising an estimated 69,000 individuals of Tegenaria domestica (Agelenidae) and more than 42,000 of Prinerigone vagans (Linyphiidae), spans a surface area of over 100 m²—representing the first documented case of colonial web formation in these species. Stable isotope analyses (δ¹³C and δ¹⁵N) revealed that the trophic web sustaining this assemblage is fueled by in situ primary production from sulfur-oxidizing microbial biofilms then transferred through chironomid larvae and adults to higher trophic levels. Morphological and molecular data confirmed the identity of the two spider species and revealed that their populations in Sulfur Cave are genetically distinct from other populations. Regarding T. domestica, we found a seasonal pattern in fecundity, with significantly larger egg clutches in early summer. Microbiome analysis of this species also revealed a lower Shannon diversity in the cave population compared with a surface individual captured nearby. Our findings unveil a unique case of facultative coloniality in this cosmopolitan spider, likely driven by resource abundance in a chemoautotrophic cave, and provide new insights into the adaptation and trophic integration of surface species in sulfidic subterranean habitats
Persistent patent omphalomesenteric duct versus persistent patent urachus in infants
No full textIntroduction: Persistent patent omphalomesenteric duct (PPOMD) and persistent patent urachus (PPU) are rare congenital anomalies that present with a persistent connection between the umbilicus and the embryonic structures of either the intestinal or the urinary tract. The two conditions are most commonly diagnosed in infancy. Aim: We exhibit a comparative clinical case report of a 3-month-old male with PPOMD and a 2-month-old male with PPU with comparable clinical presentations. No concomitant congenital anomalies were registered. The cases aim to highlight the importance of accurate diagnosis in relation to the similar clinical presentation and the appropriate surgical management of these anomalies. Results: Both patients underwent physical examination, laboratory and imaging studies, which demonstrated similar results, with the fistulogram study in Case 1 confirming a PPOMD diagnosis. The two conditions were conclusively differentiated during the following surgical explorations. Conclusion: The two conditions (PPOMD and PPU) demonstrate similar clinical presentation and belong to a broader differential diagnostic spectrum, which requires prompt diagnosis and treatment in order to prevent complications
Morpho-phylogenetic evidence reveals Pseudolomaantha thailandica gen. et sp. nov. and Submultiguttulispora multiseptata gen. et sp. nov. in Chaetosphaeriaceae
No full textAnamorphic chaetosphaeriaceous fungi exhibit high morphological variability and are distributed worldwide across terrestrial and aquatic habitats. During an ongoing taxonomic study of microfungi, two intriguing chaetosphaeriaceous hyphomycetes were collected from dead wood and dead bamboo stems in China and Thailand. A polyphasic approach, combining morphological characteristics and phylogenetic analysis of LSU and ITS sequence data, revealed that these fungi represent two new genera within Chaetosphaeriaceae. Pseudolomaantha and Submultiguttulispora are proposed for these new genera, and they exhibit non-phialidic and phialidic asexual morphs, respectively. Pseudolomaantha thailandica gen. et sp. nov. is characterized by a sporidesmium-like asexual morph with macronematous, mononematous conidiophores; monoblastic conidiogenous cells, and pyriform to obclavate, rostrate conidia bearing an apical appendage. Submultiguttulispora multiseptata gen. et sp. nov. is distinguished by macronematous, mononematous conidiophores, mono- to polyphialidic conidiogenous cells, and fusiform or ellipsoidal-fusiform, pale brown to olive green to brown conidia with filiform, hyaline appendages at both ends. Detailed descriptions, illustrations, and notes on the new collections are provided, along with a key to non-phialidic hyphomycetous genera in Chaetosphaeriaceae
Bioerosional marks in the shells of two sea turtle taxa from the middle Eocene of Belgium
No full textThis study analyses the diverse types of bioerosion marks on the shells of two sea turtle specimens from the Lutetian (middle Eocene) of Belgium. The objective is to understand the physical stressors affecting these organisms in ancient marine environments and to identify the potential factors responsible for these changes. The first specimen, the holotype of Eochelone brabantica, presents multiple erosive anomalies on its costal plates. The second individual, corresponding to Puppigerus camperi, exhibits different types of shell deviations, also of an erosive character. The combination of macroscopic and imaging techniques (i.e., CT scanning and 3D surface scanning) allow us the precise observation and identification of the different alterations. Comparative analyses suggest several external factors as potential causes of the anomalies of the two specimens (i.e., invertebrate feeding traces and trauma). This detailed examination provides specific insights into the types and causes of shell alterations in these Eocene turtles, offering a clearer understanding of their interactions in the marine ecosystem in which they lived
Diversity and distribution of caddisflies (Insecta, Trichoptera) in Singapore’s freshwater streams
No full textIn land-scarce Singapore where fresh water is a critical resource, Trichoptera communities can serve as a biomonitoring tool yet are poorly known. This study seeks to address this gap by establishing a preliminary understanding of trichopteran diversity and distribution in Singapore’s freshwater streams. From October 2023–January 2024, 11 stream sites across forested nature reserves (n = 5), buffer parks (n = 4), and urban areas (n = 2) were surveyed for trichopteran larvae. Only eight sites (four in forest streams, four in buffer streams) yielded Trichoptera, totalling 107 larval specimens comprising six families (Calamoceratidae, Ecnomidae, Hydropsychidae, Leptoceridae, Odontoceridae, and Polycentropodidae). Leptoceridae were most abundant, while Ecnomidae was the rarest, and Hydropsychidae were the most widely distributed. In this study, Trichoptera were absent from the urban streams, which had greater depth and total dissolved solids, but similar Trichoptera assemblages and environmental parameters were recorded in both forest and buffer streams. Although differences between the latter two stream types were not statistically significant, buffer streams had the highest abundance and taxonomic richness. Comparison with past literature also reveals differences in recorded Trichoptera diversity, thus this study presents an updated record for Trichoptera in Singapore’s streams. These findings further add to a baseline for future biomonitoring, research, and informing long-term freshwater conservation efforts in Singapore
Woody flora of the Prof. Dr. Karl Arens Reserve, Corumbataí, São Paulo, Brazil
No full textThis study was conducted in the Prof. Dr. Karl Arens Reserve, Corumbataí, São Paulo. The area is a Cerrado fragment, with no records of fire since 1962 and is characterised by the predominance of Cerradão phytophysiognomy. Although several studies have been conducted in the Reserve, there was no testimony material for some species in the Herbarium Rioclarense (HRCB), nor a list of vouchers for any taxon in the main publications. Thus, the objective of this work was to undertake a floristic survey of the woody species in the Reserve, based on herbarium specimens and fieldwork.The survey in HRCB recorded 510 exsiccatae belonging to 160 species and 44 families. We also conducted 24 fieldwork expeditions between 2019 and 2021 and recorded 118 species in 39 families. In total, 193 woody species were recorded for the Reserve in Corumbataí. Species such as Copaifera langsdorffii and Myrcia neoclusiifolia had already been cited for the area, but there was no testimony material in the herbarium. Machaerium nyctitans and Alchornea glandulosa are examples of new records for the Reserve. Fabaceae, Asteraceae, Myrtaceae, Melastomataceae and Rubiaceae were the families with the greatest species diversity