The Serverless Computing Survey: A Technical Primer for Design Architecture

The development of cloud infrastructures inspires the emergence of cloud-native computing. As the most promising architecture for deploying microservices, serverless computing has recently attracted more and more attention in both industry and academia. Due to its inherent scalability and flexibility, serverless computing becomes attractive and more pervasive for ever-growing Internet services. Despite the momentum in the cloud-native community, the existing challenges and compromises still wait for more advanced research and solutions to further explore the potentials of the serverless computing model. As a contribution to this knowledge, this article surveys and elaborates the research domains in the serverless context by decoupling the architecture into four stack layers: Virtualization, Encapsule, System Orchestration, and System Coordination. Inspired by the security model, we highlight the key implications and limitations of these works in each layer, and make suggestions for potential challenges to the field of future serverless computing.

Le problème de l’identité culturelle dans les romans Tout s’effondre de Chinua Achebe et Un nom pour un autre de Jhumpa Lahiri

The novels Things Fall Apart by Chinua Achebe and The Namesake by Jhumpa Lahiri approach an acute and sensitive problem of the effects of colonization and of the self-exiled emigrant man. Each of the protagonists of these two novels expresses an upheaval, an inner cultural conflict. It turns out that their destiny is in a close connection with their images and emotional valences, strongly fed by a collective imaginary, by the deep reality of collective life. Thus, adherence and communication with the archetypal resources of the native community, with the essential that precedes the human condition, proves to be a vital necessity, of overwhelming importance for our protagonists.

Students’ and Teachers’ Perceptions on the Impacts of Service-Learning in a Language Course

Service-learning, also known as community-based learning, is considered a pedagogical tool in various disciplines at different levels, including tertiary education. It has proved its significant effects on social and academic aspects. Different institutions have incorporated service-learning in their language curricula in language education to create better exposure to the target language for learners. However, the research on the application of service-learning components in language learning has still been limited in Asia-Pacific countries, especially in Vietnam, where learners have fewer chances of serving a native community by using a target language like English. This paper reports on teachers’ and students’ perspectives on the impacts of a service-learning project incorporated in an English speaking course at a public university in Vietnam. The study used questionnaires for 117 second-year English-majored students, three focus-group discussions with 16 surveyed students, and semi-structured individual interviews with four subject teachers. The results reflect students’ positive feedback on language competence, social awareness, personal traits and soft skills. The interviews with teachers reveal the progressive changes in students’ presentation skills, self-confidence, and critical thinking skills. However, the main difficulties hindering the implementation of the project are the insufficient understanding of project procedures, the passive way of thinking, lack of financial support, and the limited exposure to English in authentic environments. This paper also brings about some practical implications for language teachers and researchers in similar educational contexts.

Long-Term Coexistence of Two Invasive Vespid Wasps in NW Patagonia (Argentina)

In Patagonia (Argentina) two non-native vespid wasps became established in the last decades. Vespula germanica was first detected in 1980 while V. vulgaris arrived some 30 years later. Both species can have a strong negative impact on agriculture, natural environment and on outdoor human activities. Invasion success -the establishment and spread of a species- may be influenced negatively by the degree of interaction with the resident native community, and alien species already present. The sequential arrival of these two wasps allows us to understand key questions of invasion ecology. Additionally, recognizing the outcome of the invasion by vespids in Patagonia -a region lacking native social wasps-, may help plan species-focused mitigation and control strategies. We explored long term species coexistence through the deterministic Lotka-Volterra competition model, using site-specific field data on prey captured (to estimate niche overlap) and current nest densities in sites. Food items carried by workers were similar but there is some degree of segregation. V. germanica nest density in shared sites, and in sites without coexistence, were 3.14 and 3.5 respectively, being higher for V. vulgaris with 4.71 and 5.33. The model predicts stable co-existence of both species in the invaded range, yet a higher abundance of V. vulgaris should be expected. Added to evidence on other foraging behavioral attributes of both wasp species and the invasion patterns observed in other regions, it is likely that the prior presence of V. germanica does not contribute significantly to the biotic resistance of the invaded range for V. vulgaris

Changes in native and introduced host–parasite networks

Introduced species can alter the dynamics and structure of a native community. Network analysis provides a tool to study host–parasite interactions that can help to predict the possible impact of biological invasions or other disturbances. In this study, we used weighted bipartite networks to assess differences in the interaction patterns between hosts and helminth parasites of native (Sea of Japan) and invasive (Black Sea and Sea of Azov) populations of Planiliza haematocheilus (Teleostei: Mugilidae). We employed three quantitative network descriptors, connectance, weighted nestedness and modularity, to gain insight into the structure of the host–parasite networks in the native and invaded areas. The role of parasite species in the networks was assessed using the betweenness centrality index. We analyzed networks encompassing the whole helminth community and subsets of species classified by their transmission strategy. The analyses were downscaled to host individual-level to consider intraspecific variation in parasite communities. We found significant differences between networks in the native and invaded areas. The latter presented a higher value of nestedness, which may indicate a co-occurrence between parasite species with many connections in the network and species with fewer interactions within the same individual-host. In addition, modularity was higher in the native area’s networks than those of the invaded area, with subgroups of host individuals that interact more frequently with certain parasite species than with others. Only the networks composed of actively transmitted parasites and ectoparasites did not show significant differences in modularity between the Sea of Azov and the Sea of Japan, which could be due to the introduction of a part of the native community into the invaded environment, with a lower diversity and abundance of species. We show that network analysis provides a valuable tool to illuminate the changes that occur in host–parasite interactions when an invasive species and its parasite community are introduced into a new area.

Developing English Learning Environment for Non-English Majors in a Non-native Community

Teaching and learning English as a foreign language in a non-native community poses a lot of challenges to both teachers and students. While it is commonly shared that in-class learning does not guarantee the success of the learning, the need for the extension of learning opportunities beyond the class has been remarkably increasing, encouraging English educators to create an environment for English learning beyond the class door. This study aims to set up such environment for non-English majors at Thai Nguyen University of Education, Vietnam. A series of out-of-class English activities were conducted during October 2020 to May 2021 for non-English majors at the University. 200 students joined the study as questionnaire respondents in two phases (before and after the implement of the activities) and 10 students were selected for focus group interview. Results revealed that the majority of the students believed in-class English learning were insufficient for their demands and needs and thus expected similar activities should be carried out beyond the class. The research would be a significant case study to illustrate that efforts to include out-of-class activities in the learning process should be encouraged for the development of an extended language learning environment for the benefits of the students in places where English is largely limited within the classroom walls.

Hiking and Livestock Favor Non-Native Plants in The High Andes

Hikers and livestock using mountain trails damage native vegetation and act as seed vectors, thus favouring the spread of non-native plants. We evaluated the effect of trails and livestock abundance on the success of non-native plants in the arid central Andes of Argentina. We surveyed six trails, covering elevations between 2400 m and 3570 m a.s.l. and recorded non-native and native vegetation using transects distributed along the elevational gradient and spanning distances up to 22 m from the trail. We assessed how non-native occurrence, richness and cover varied with distance from the trail, intensity of use by livestock, native plant community composition and elevation. We found that trails favoured non-native occurrence, but did not influence richness and cover, while livestock favoured non-native occurrence, richness and cover. Non-native richness and cover decreased with elevation and varied with native community composition. In addition, non-native richness was positively correlated with native shrub cover suggesting possible facilitative interactions. Our results show that despite strong environmental filtering that decreases non-native abundance with elevation, non-natives occur up to the upper limits of vegetation, and that trails and livestock favour their spread in the mountains.

Resuming Gynocratic Principles: Cultural Reterritorialization of Native Traditions in Linda Hogan’s Fiction

Native Americans’ cultural system has been utterly undermined in the early colonial conquest and the later neo-colonial expansion. Cultural annihilation is primarily caused by the forced cultural assimilation, especially by the white government’s practice of eradicating native traditions and beliefs. To rebuild the native culture system, Native American writer Linda Hogan attempts to employ the pre-colonial gynocratic principles in her literary creation, thus reterritorializing their cultural identity among the modern natives. This paper reveals how Hogan effectively resumes the ancient gynocratic principles by portraying a series of typical female images in the woman-centered native community, with an aim to fight against cultural assimilation guided by the white male-dominated western metaphysical epistemology.

Competitive trait hierarchies of native communities and invasive propagule pressure consistently predict invasion success during grassland establishment

Invasive non-native plants challenge ecosystems restoration, and understanding the factors that determine the establishment of invasive plants is crucial to improve restoration outcomes. However, the drivers of invasibility of plant communities are not sufficiently clear, and combined effects are not understood. Therefore, we investigated the contribution of the main drivers of invasion success during early phases of restoration, i.e., biotic resistance, invasive propagule pressure, and environmental fluctuations. We compared the contribution of these drivers in a series of mesocosms experiments using designed grasslands as a model system, and Solidago gigantea as invasive model species. Two grassland communities were designed according to competitive trait hierarchies with different sowing patterns, reflecting variation in biotic resistance. We then manipulated invader propagule pressure and applied different scenarios of environmental fluctuation, i.e., flood, heat, and N fertilization. Invasive biomass was considered as proxy for invasion success, while native biomass represented restoration success. There were consistent effects of biotic resistance to S. gigantea invasion via competitive trait hierarchies in the three experiments. Communities dominated by species with high-competition traits were more resistant regardless of environmental fluctuation. Clumped seeding of the native community reduced invasibility, whereas high non-native propagule density increased invasion. The effects of environmental fluctuation were less consistent and context-dependent, thus playing a secondary role when compared to biotic drivers of invasion. Restoration initiatives on grasslands impacted by invasive plants should consider biotic resistance of the restored community as a key driver and the importance of controlling further arrivals of invasive species during community assembly.