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Climate change, biodiversity loss, and chemical pollution are planetary-scale emergencies requiring urgent mitigation actions. As these "triple crises" are deeply interlinked, they need to be tackled in an integrative manner. However, while climate change and biodiversity are often studied together, chemical pollution as a global change factor contributing to worldwide biodiversity loss has received much less attention in biodiversity research so far. Here, we review evidence showing that the multifaceted effects of anthropogenic chemicals in the environment are posing a growing threat to biodiversity and ecosystems. Therefore, failure to account for pollution effects may significantly undermine the success of biodiversity protection efforts. We argue that progress in understanding and counteracting the negative impact of chemical pollution on biodiversity requires collective efforts of scientists from different disciplines, including but not limited to ecology, ecotoxicology, and environmental chemistry. Importantly, recent developments in these fields have now enabled comprehensive studies that could efficiently address the manifold interactions between chemicals and ecosystems. Based on their experience with intricate studies of biodiversity, ecologists are well equipped to embrace the additional challenge of chemical complexity through interdisciplinary collaborations. This offers a unique opportunity to jointly advance a seminal frontier in pollution ecology and facilitate the development of innovative solutions for environmental protection.
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Ecossistema , Poluição Ambiental , Biodiversidade , Ecologia , Conservação dos Recursos Naturais , Mudança ClimáticaRESUMO
Despite the extensive coverage in the literature, limited attention has been paid to the investigation of technostress among academicians who work under special circumstances, such as occupation, and might have different psychological states due to those conditions. To fill this gap, this study examined the level and factorial structure of technostress among 573 Palestinian academicians who worked in a more-than-seventy-years occupied country, and with the addition of the COVID-19 pandemic. A sequential mixed method approach with confirmatory and exploratory factor analysis was used to explore the technostress factors and to measure their level among the academicians. The obtained findings indicated that the four factors of (1) schedule overload, (2) complexity, (3) uncertainty and uselessness, and (4) invasion and compulsion formed the model of techno-stressors among Palestinian academicians. This can help various stakeholders (researchers, policy makers, practitioners, etc.) to design the needed interventions accordingly and reduce the technostress among academicians; hence, enhancing the latter's teaching practices and experiences.
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Intelligent Tutoring Systems (ITSs) have a great potential to effectively transform teaching and learning. As more efforts have been put on designing and developing ITSs and integrating them within learning and instruction, mixed types of results about the effectiveness of ITS have been reported. Therefore, it is necessary to investigate how ITSs work in real and natural educational contexts and the associated challenges of ITS application and evaluation. Through a systematic literature review method, this study analyzed 40 qualified studies that applied social experiment methods to examine the effectiveness of ITS during 2011-2022. The obtained results highlighted a complicated landscape regarding the effectiveness of ITS in real educational contexts. Specifically, there was an "intelligent" regional gap regarding the distribution of countries where ITS studies using social experiment methods were conducted. Compared to learning performance, relatively less attention was paid to investigating the impact of ITS on non-cognitive factors, process-oriented factors, and social outcomes, calling for more research in this regard. Considering the complexities and challenges existing in real educational fields, there was a lack of scientific rigor in terms of experimental design and data analysis in some of the studies. Based on these findings, suggestions for future study and implications were proposed.
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Preventing and remedying fresh waters from chemical pollution is a fundamental societal and scientific challenge. With other nonchemical stressors potentially co-occurring, assessing the ecological consequences of reducing chemical loads in the environment is arduous. In this case study, we comparatively assessed the community structure, functions, and tolerance of stream biofilms to micropollutant mixtures extracted from deployed passive samplers at wastewater treatment plant effluents. These biofilms were growing up- and downstream of one upgraded and two nonupgraded wastewater treatment plants before being sampled for analyses. Our results showed a substantial decrease in micropollutant concentrations by 85%, as the result of upgrading the wastewater treatment plant at one of the sampling sites with activated carbon filtration. This decrease was positively correlated with a loss of community tolerance to micropollutants and the recovery of the community structure downstream of the effluent. On the other hand, downstream biofilms at the nonupgraded sites displayed higher tolerance to the extracts than the upstream biofilms. The observed higher tolerance was positively linked to micropollutant levels both in stream water and in biofilm samples, and to shifts in the community structure. Although more investigations of upgraded sites are needed, our findings point toward the suitability of using community tolerance for the retrospective assessment of the risks posed by micropollutants, to assess community recovery, and to relate effects to causes in complex environmental conditions.
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Poluentes Químicos da Água , Biofilmes , Água Doce , Estudos Retrospectivos , Águas Residuárias , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidadeRESUMO
With the accelerated use of silver nanoparticles (AgNP) in commercial products, streams will increasingly serve as recipients of, and repositories for, AgNP. This raises concerns about the potential toxicity of these nanomaterials in the environment. Here we aimed to assess the impacts of chronic AgNP exposure on the metabolic activities and community structure of fungal and bacterial plant litter decomposers as central players in stream ecosystems. Minimal variation in the size and surface charge of AgNP indicated that nanoparticles were rather stable during the experiment. Five days of exposure to 0.05 and 0.5 µM AgNP in microcosms shifted bacterial community structure but had no effect on a suite of microbial metabolic activities, despite silver accumulation in the decomposing leaf litter. After 25 days, however, a broad range of microbial endpoints, as well as rates of litter decomposition, were strongly affected. Declines matched with the total silver concentration in the leaves and were accompanied by changes in fungal and bacterial community structure. These results highlight a distinct sensitivity of litter-associated microbial communities in streams to chronic AgNP exposure, with effects on both microbial functions and community structure resulting in notable ecosystem consequences through impacts on litter decomposition and further biogeochemical processes.
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Rios/microbiologia , Prata/toxicidade , Ecossistema , Fungos/efeitos dos fármacos , Nanopartículas , Folhas de Planta/químicaRESUMO
Silver nanoparticles (AgNP) are increasingly used as antimicrobials in consumer products. Subsequently released into aquatic environments, they are likely to come in contact with microbial communities like periphyton, which plays a key role as a primary producer in stream ecosystems. At present, however, very little is known about the effects of nanoparticles on processes mediated by periphyton communities. We assessed the effects of citrate-coated silver nanoparticles and silver ions (dosed as AgNO3) on five functional end points reflecting community and ecosystem-level processes in periphyton: photosynthetic yield, respiration potential, and the activity of three extracellular enzymes. After 2 h of exposure in experimental microcosms, AgNP and AgNO3 inhibited respiration and photosynthesis of periphyton and the activities of two of the three extracellular enzymes. Addition of a chelating ligand that complexes free silver ions indicated that, in most cases, toxicity of AgNP suspensions was caused by Ag(I) dissolved from the particles. However, these suspensions inhibited one of the extracellular enzymes (leucine aminopeptidase), pointing to a specific nanoparticle effect independent of the dissolved Ag(I). Thus, our results show that both silver nanoparticles and silver ions have potential to disrupt basic metabolic functions and enzymatic resource acquisition of stream periphyton.
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Organismos Aquáticos/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Fotossíntese/efeitos dos fármacos , Prata/toxicidade , Poluentes da Água/análise , Quelantes/química , Ecossistema , Exposição Ambiental , Íons , Ligantes , Nanopartículas , Nanotecnologia , Rios , Nitrato de Prata/química , Nitrato de Prata/toxicidade , Unitiol/químicaRESUMO
This study aimed to explore the use of antioxidant enzyme activities (AEA) and biofilm metal accumulation capacity in natural communities as effect-based indicator of metal exposure in fluvial systems. To achieve these objectives, an active biomonitoring using fluvial biofilm communities was performed during 5 weeks. Biofilm was colonized over artificial substrata in a non-polluted site. After 5 weeks, biofilms were translocated to four different sites with different metal pollution in the same stream. The evolution of environmental parameters as well as biofilm responses was analysed over time. Physicochemical parameters were different between sampling times as well as between the most polluted site and the less polluted ones, mainly due to Zn pollution. In contrast, AEA and metal accumulation in biofilms allowed us to discriminate the high and moderate metal pollution sites from the rest. Zn, the metal with the highest contribution to potential toxicity, presented a fast and high accumulation capacity in biofilms. According to the multivariate analysis, AEA showed different responses. While catalase (CAT) and ascorbate peroxidase (APX) variability was mainly attributed to environmental stress (pH, temperature and phosphate concentration), glutathione-S-transferase (GST) changes were related to metal pollution. Glutathione reductase (GR) and superoxide dismutase (SOD) responses were related to both stress factors. AEA and metal accumulation are proposed as sensitive effect-based field methods, to evaluate biofilm responses after acute metal exposure (e.g. an accidental spill) due to their capacity to respond after few hours, but also in routinely monitoring due to their persistent changes after few weeks of exposure. These tools could improve the Common Implementation Strategy (CIS) of the Water Framework Directive (WFD) as expert group request.
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Biofilmes/efeitos dos fármacos , Biomarcadores/análise , Monitoramento Ambiental , Rios/química , Rios/microbiologia , Poluentes Químicos da Água/toxicidade , Zinco/toxicidade , Ativação Enzimática/efeitos dos fármacos , Enzimas/metabolismo , Metais/metabolismo , Metais/toxicidade , Análise Multivariada , Tempo , Poluentes Químicos da Água/análiseRESUMO
In the aquatic environment, microplastic particles (MP) can accumulate in microbial communities that cover submerged substrata, i.e. in periphyton. Despite periphyton being the essential food source for grazers in the benthic zones, MP transfer from periphyton to benthic biota and its ecotoxicological consequences are unknown. Therefore, in this study, we investigated the effects of 1) MP on embryonal development of freshwater gastropod Physa acuta embryos, 2) MP on adult Physa acuta individuals through dietary exposure and 3) on the MP surface properties. Embryonal development tests were carried out with spherical polyethylene MP in the size of 1-4 µm (MP). Over a period of 28 days, embryonal development and hatching rate were calculated. In the feeding experiments, periphyton was grown in the presence and absence of MP and was then offered to the adult Physa acuta for 42-152 h. The snails readily ingested and subsequently egested MP, together with the periphyton as shown by MP quantification in periphyton, snail soft body tissue and feces. No selective feeding behavior upon MP exposure was detected. The ingestion of MP had no effect on mortality, feeding and defecation rate. Yet, the reproductive output of snails, measured as the number of egg clutches and numbers of eggs per clutch, decreased after the ingestion of MPs, while the hatching success of snail embryos those parents were exposed remained unaffected. In contrast, hatching rate of snail embryos was significantly reduced upon direct MP exposure. MP optical properties were changed upon the incorporation into the periphyton and the passage through the digestive tract. Our results indicate that MP incorporated in periphyton are bioavailable to aquatic grazers, facilitating the introduction of MP into the food chain and having direct adverse effects on the grazers' reproductive fitness.
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Perifíton , Caramujos , Poluentes Químicos da Água , Humanos , Microplásticos , Plásticos/toxicidade , Água Doce , Cadeia Alimentar , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análiseRESUMO
Textbooks have a crucial role in shaping students' knowledge, behaviors, and attitudes in different school subjects. This study compares the structure and content of science textbooks of grade nine in Egypt and China to reveal the common and different features in the textbook design. It opts for a horizontal analysis of four science textbooks in the associated countries. The results revealed that the distribution of science subjects has partial similarities to some extent among the preparatory stage between the Chinese and Egyptian science textbooks besides the overlapping in the associated topics, presenting Biology as a common subject of interest. Moreover, the number of activities distributed within units and subjects have the highest shares in the Chinese textbooks, and most of the activities in the Egyptian textbooks focused on Chemistry and Physics subjects. In addition to the structure analysis, this study also explored the textbooks content in both countries, covering three dimensions: (1) cognitive expectations, (2) learning goals, and (3) efficiency of illustration. The results provide valuable insights for textbook designers and curriculum developers to enhance the quality of science curricula and textbooks. Therefore, the study recommends considering instructional design and lesson plans when distributing the learning activities and developing international standards for designing school science textbooks.
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The severe acute respiratory syndrome coronavirus 2 (SARS COV2) had rapidly spread and caused a global pandemic worldwide. The most common symptoms in adults are respiratory with dry cough, dyspnea, and fever. Occasionally, extra-respiratory presentations may be seen such as gastrointestinal involvement with diarrhea, vomiting or abdominal pain. Acute intestinal intussusception is the most common cause of bowel obstruction in infants (2-4 months of age) but rarely could it be encountered in adult. It is a very rare gastro-intestinal manifestation of COVID-19 with an invagination of a segment of the bowel within a more distal one. The part that prolapses into the other is called the intussusceptum, and the part that receives it is called the intussuscipiens. Most of COVID-19 cases of AII are reported in the pediatric population between 4 and 10 months. Only a single case of small bowel obstruction secondary to ileo-colic intussusception in a COVID-19 infection adult was published on April 2021. We present here a challenging case of intussusception secondary to COVID-19 infection in an adult in the absence of respiratory symptoms. Our study presents the first case in Africa of AII in adult patients due to COVID-19.
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Personality is considered as the internal factor that defines a person's behavior. Therefore, providing adaptive features and personalized support in online learning by considering learners' personalities can improve their learning experiences and outcomes. In this context, several research studies have investigated the impact of personality differences in online learning. However, little is known about how personality differences affect learners' behavior while learning. To fill this gap, this study applies a lag sequential analysis (LSA) approach to understand learners' navigational behavior patterns in an online three-months course of 65 learners based on their personalities. In this context, the five factor model (FFM) model was used to identify learners' personalities. The findings revealed that learners with different personalities use different strategies to learn and navigate within the course. For instance, learners high in extraversion tend to be extrinsically motivated. They therefore significantly navigated between viewing the course module and their personal achievements. The findings of this study can contribute to the adaptive learning field by providing insights about which personalization features can help learners with different personalities. The findings can also contribute to the field of automatic modeling of personality by providing information about differences in navigational behavior based on learners' personalities.
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BACKGROUND: Peritoneal cystic echinococcosis happens usually after traumatic rupture or after surgical treatment. Primary peritoneal cystic echinococcosis is a very rare case that constitutes a diagnostic and therapeutic challenge. CASE REPORT: A 30-year-old Tunisian man was admitted for hypogastric pain since 4 months. He has a 10 cm hypogastric mass. Biological-tests were normal. A computed tomography Scan showed a cystic mass on the pelvis measuring 13 × 17 cm without echinococcosis cyst in the liver. The patient was operated and we found a cystic mass of 17 cm located on the Douglas cul-de-sac that suggest a pelvic hydatid cyst. We have performed an aspiration of the cyst confirms the diagnosis followed by injection of hypertonic solution, extarction of the germinal layer and a maximal reduction of the pericyst. The postoperative course was uneventful. CONCLUSION: Trough our case, we try to focus on the diagnosis and therapeutic options of this rare entity that we should think of in front of a patient with isolated peritoneal cyst especially in endemic country.
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Cistos , Equinococose , Doenças Peritoneais , Masculino , Humanos , Adulto , Peritônio/diagnóstico por imagem , Peritônio/cirurgia , Equinococose/diagnóstico por imagem , Equinococose/cirurgia , Doenças Peritoneais/diagnóstico por imagem , Doenças Peritoneais/cirurgia , Dor Abdominal/etiologia , Cistos/complicaçõesRESUMO
Phototrophic biofilms, also known as periphyton, are microbial freshwater communities that drive crucial ecological processes in streams and lakes. Gaining a deep mechanistic understanding of the biological processes occurring in natural periphyton remains challenging due to the high complexity and variability of such communities. To address this challenge, we rationally developed a workflow to construct a synthetic community by co-culturing 26 phototrophic species (i.e., diatoms, green algae, and cyanobacteria) that were inoculated in a successional sequence to create a periphytic biofilm on glass slides. We show that this community is diverse, stable, and highly reproducible in terms of microbial composition, function, and 3D spatial structure of the biofilm. We also demonstrate the ability to monitor microbial dynamics at the single species level during periphyton development and how their abundances are impacted by stressors such as increased temperature and a herbicide, singly and in combination. Overall, such a synthetic periphyton, grown under controlled conditions, can be used as a model system for theory testing through targeted manipulation.
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Cianobactérias , Diatomáceas , Herbicidas , Perifíton , Água Doce/químicaRESUMO
Trichobezoars are foreign and indigestible materials in the gastrointestinal tract and are usually found in psychiatric females, who often deny eating their own hair, but also at situations of gastric dysmotility and prior gastric surgery. Although rare, gastric trichobezoar should not be forgotten as a differential diagnosis in females presenting with vague epigastric pain. Its treatment well in time will prevent complications.
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BACKGROUND: Hydatid disease is endemic in Mediterranean countries and most commonly occurs in the liver followed by the lung. A primary localization in the retroperitoneum is extremely rare. CASE PRESENTATION: We report the case of a 29-year-old Tunisian patient presenting with progressive left flank pain and skin urticaria. On abdominal ultrasonography and computed tomography scan, a ruptured retroperitoneal hydatid cyst was diagnosed, which was confirmed by positive hydatid serology. The treatment consisted of resection of protruding dome. The evolution was favorable. No local recurrence was detected during postoperative follow-up. CONCLUSIONS: Primary retroperitoneal hydatid cyst is extremely rare and has uncommon presentation, but we should learn the keys to its diagnosis. In endemic regions, high suspicion for this disease is justified regardless of localization.
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Cistos , Equinococose , Adulto , Equinococose/diagnóstico , Equinococose/diagnóstico por imagem , Humanos , Espaço Retroperitoneal/diagnóstico por imagem , Ruptura , Tomografia Computadorizada por Raios X , UltrassonografiaRESUMO
Although several studies have been conducted to summarize the progress of open educational resources (OER) in specific regions, only a limited number of studies summarize OER in Africa. Therefore, this paper presents a systematic literature review to explore trends, themes, and patterns in this emerging area of study, using content and bibliometric analysis. Findings indicated three major strands of OER research in Africa: (1) OER adoption is only limited to specific African countries, calling for more research and collaboration between African countries in this field to ensure educational equity; (2) most of the OER initiatives in Africa have focused on the creation process and neglected other important perspectives, such as dissemination and open educational practices (OEP) using OER; and (3) on top of the typical challenges for OER adoption (e.g., infrastructure), other personal challenges were identified within the African context, including culture, language, and personality. The findings of this study suggest that more initiatives and cross-collaborations with African and non-African countries in the field of OER are needed to facilitate OER adoption in the region. Additionally, it is suggested that researchers and practitioners should consider individual differences, such as language, personality and culture, when promoting and designing OER for different African countries. Finally, the findings can promote social justice by providing insights and future research paths that different stakeholders (e.g., policy makers, educators, practitioners, etc.) should focus on to promote OER in Africa.
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Disciplinas das Ciências Biológicas/educação , Biologia Computacional/normas , Educação a Distância/normas , Pesquisadores/educação , África , Bibliometria , Humanos , Pesquisadores/estatística & dados numéricosRESUMO
Microbial life in natural biofilms is dominated by prokaryotes and microscopic eukaryotes living in dense association. In stream ecosystems, microbial biofilms influence primary production, elemental cycles, food web interactions as well as water quality. Understanding how biofilm communities respond to anthropogenic impacts, such as wastewater treatment plant (WWTP) effluent, is important given the key role of biofilms in stream ecosystem function. Here, we implemented 16S and 18S rRNA gene sequencing of stream biofilms upstream (US) and downstream (DS) of WWTP effluents in four Swiss streams to test how bacterial and eukaryotic communities respond to wastewater constituents. Stream biofilm composition was strongly affected by geographic location - particularly for bacteria. However, the abundance of certain microbial community members was related to micropollutants in the wastewater - among bacteria, micropollutant-associated members were found e.g. in Alphaproteobacteria, and among eukaryotes e.g. in Bacillariophyta (algal diatoms). This study corroborates several previously characterized responses (e.g. as seen in diatoms), but also reveals previously unknown community responses - such as seen in Alphaproteobacteria. This study advances our understanding of the ecological impact of the current wastewater treatment practices and provides information about potential new marker organisms to assess ecological change in stream biofilms.
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Microbiota , Águas Residuárias , Efeitos Antropogênicos , BiofilmesRESUMO
Effluents of wastewater treatment plants can impact microbial communities in the receiving streams. However, little is known about the role of microorganisms in wastewater as opposed to other wastewater constituents, such as nutrients and micropollutants. We aimed therefore at determining the impact of wastewater microorganisms on the microbial diversity and function of periphyton, key microbial communities in streams. We used a flow-through channel system to grow periphyton upon exposure to a mixture of stream water and unfiltered or ultra-filtered wastewater. Impacts were assessed on periphyton biomass, activities and tolerance to micropollutants, as well as on microbial diversity. Our results showed that wastewater microorganisms colonized periphyton and modified its community composition, resulting for instance in an increased abundance of Chloroflexi and a decreased abundance of diatoms and green algae. This led to shifts towards heterotrophy, as suggested by the changes in nutrient stoichiometry and the increased mineralization potential of carbon substrates. An increased tolerance towards micropollutants was only found for periphyton exposed to unfiltered wastewater but not to ultra-filtered wastewater, suggesting that wastewater microorganisms were responsible for this increased tolerance. Overall, our results highlight the need to consider the role of wastewater microorganisms when studying potential impacts of wastewater on the receiving water body.