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Investigating the Role of bS21 in Vancomycin-Resistant Staphylococcus aureus
Get PDFStaphylococcus aureus is a Gram-positive pathogenic bacterium commonly known for being the causative organism of staph infections in clinical settings. In previous literature, it has been observed that mutations in certain genes in S. aureus can result in resistance to commonly used antibiotics. Specifically, mutations in the gene rpsU, encoding the ribosomal protein bS21, have been present in strains of S. aureus resistant to the antibiotic vancomycin. The aim of my project is to validate these findings by creating a strain of S. aureus without bS21 and performing an antibiotic assay to determine the level of resistance to vancomycin in this strain. To do this, I have been working to create a plasmid that can be introduced into wild-type S. aureus and knock out the gene rpsU via homologous recombination. To create the desired plasmid, I am modifying the pIMAY-Z plasmid which contains the gene for chloramphenicol resistance; I began by amplifying two desired sequences (also referred to as flanking regions) via PCR that will be inserted into the plasmid. I then performed a restriction enzyme digest to cut the plasmid at the insertion sites, along with cutting the amplified sequences at their ends so that they can be added to the plasmid. I continued by performing a ligation to join the flanking regions to the ends of the pIMAY-Z backbone and effectively “glue” the entire plasmid together. I used this ligation to transform chemically competent IMO8B E. coli cells on Luria-Bertani agar plates containing 25 ug/ml chloramphenicol, which amplified the desired plasmid for use in further steps. Although I have not confirmed whether this plasmid has been successfully produced through the digests, ligations, and transformations I have performed so far, the positive and negative controls have been successful, and I am now just waiting on official confirmation through sequencing
A Commentary on the Dynamics of the Local and the Global, and the Representations of Minorities in Mediascapes
Get PDFThis commentary intends to extend knowledge about local identities with regard to their representations in the mediascape. It uses two focal MGDR papers and uncovers the opportunities for local identities to develop in global-local dynamics. This commentary reminds the interdependence between the global and the local and how local identities are formed. We discuss the accessibility of local identities and cultures
Groundwater quality: Global threats, opportunities and realising the potential of groundwater
No full textGroundwater is a critical resource enabling adaptation due to land use change, population growth, environmental degradation, and climate change. It can be a driver of change and adaptation, as well as effectively mitigate impacts brought about by a range of human activities. Groundwater quality is key to assessing groundwater resources and we need to improve our understanding and coverage of groundwater quality threats if we are to use groundwater sustainably to not further burden future generations by limiting resources and/or increasing treatment or abstraction costs. Good groundwater quality is key to progress on a range of Sustainable Development Goals, but achievement of those goals most affected by groundwater contamination is often hindered by of a lack of resources to enable adaptation. A range of threats to groundwater quality exist, both natural and anthropogenic, which may constrain groundwater use. However, groundwater often provides good quality water for a range of purposes and is the most important water resource in many settings. This special issue explores some of the key groundwater quality challenges we face today as well as the opportunities good groundwater quality and treatment solutions bring to enhance safe groundwater use. Legacy anthropogenic contaminants and geogenic contaminants may be well documented in certain places, such as N America, Europe and parts of Asia. However, there is a real issue of data accessibility in some regions, even for more common contaminants. This paucity of information can restrict our understanding and ability to manage and protect groundwater sources. Compared to surface water quality, large scale assessments for groundwater quality are still scarce and often rely on inadequate data sets. Better access to existing data sets and more research is needed on many groundwater quality threats. Identification and quantification of these threats will support the wise use and protection of this subsurface resource, allow society to adequately address future challenges, and help communities realise the full potential of groundwater
HARDeNN: Hardware-assisted attack-resilient deep neural network architectures
No full textWe propose HARDeNN, a low-overhead end-to-end inference accelerator methodology to armor the underlying pre-trained neural network architecture against black-box non-input adversarial attacks. In order to find the most vulnerable neural network architectures parameters, a hardware-assisted fault injection tool and a statistical stress model have been proposed to synergy uniform fault assessment across layers and targeted in-layer fault assessment to realize a holistic, rigorous fault evaluation in NN topologies susceptible to non-input adversarial black-box attacks. The key observation from the assessment shows that the weights and activation functions are the most vulnerable neural network parameters that are susceptible to both single-bit and multiple-bit flip attacks. Concerning the aforementioned parameters, a multi-objective design space exploration is conducted to find a superior design under different resource constraints. The error-resiliency magnitude offered by HARDeNN can be adjusted based on the given boundaries. The experimental results show that HARDeNN methodology enhances the error-resiliency magnitude of cnvW1A1 by 17.19% and 96.15% for 100 multi-bit upsets that target weight and activation layers, respectively, during CIFAR-10 classification.© 2017 Elsevier Inc. All rights reserved
A Parametric Study on a Paper-Based Bi-Material Cantilever Valve
Get PDFThe novel paper-based Bi-Material Cantilever (B-MaC) valve allows the autonomous loading and control of multiple fluid reagents which contributes to the accurate operation of paper-based microfluidic devices utilized for biological and chemical sensing applications. In this paper, an extensive parametric study is presented to evaluate the effects of key geometric parameters of the valve, such as paper direction, cantilever width, paper type, tape type, and sample volume, in addition to the effects of relative humidity and temperature on the functionality of the B-MaC and to provide a better understanding of the rate of fluid flow and resulting deflection of the cantilever. Machine direction, cantilever width, paper type, and tape type were found to be important parameters that affect the B-MAC’s activation time. It was also observed that the rate of fluid imbibition in the B-MaC is considerably affected by change in humidity for high (55 °C) and low (25 °C) temperatures, while humidity levels have no significant effect during imbibition in the B-MaC at an ambient temperature of 45 °C. It was also found that a minimum distance of 4 mm is required between the B-MaC and the stationary component to prevent accidental activation of the B-MaC prior to sample insertion when relative humidity is higher than 90% and temperature is lower than 35 °C. The rate of fluid imbibition that determines the wetted length of the B-MaC and the final deflection of the cantilever are critical in designing and fabricating point-of-care microfluidic paper-based devices. The B-MaC valve can be utilized in a fluidic circuit to sequentially load several reagents, in addition to the sample to the detection area
From chaos to a new normal—the COVID-19 pandemic as experienced by municipal health and social care providers in Sweden: A qualitative study
Get PDFWhen the COVID-19 pandemic began to spread around the world, Swedish municipalities were unprepared. Different guidelines on how to act in relation to the disease varied and protective equipment was lacking. This study aims to describe the experiences of health and social care providers of working at municipality level during the COVID-19 pandemic. A total of 12 assistant nurses, 13 registered nurses, and three physicians were interviewed, individually or in groups, between fall 2020 and spring 2021. The interviews were semi-structured and were analyzed using thematic analysis, utilizing a design following the COREQ-checklist. Three main themes were identified as follows: ‘Initial chaotic situation and uncertainty regarding how to deal with the pandemic’; ‘Continuous changes in organization and work routines’, and ‘Management of the pandemic has become the new normal’. Though health and social care workers eventually managed to embed dealing with COVID-19 as a routine feature of their daily work, municipalities must prepare for future crises
Designing Classroom Practices for Teaching Online Inquiry: Experiences from the Field
Get PDFStudents face several challenges when asked to locate relevant and credible information from the internet. This article introduces three principles for designing online inquiry lessons and documents what we learned from five language arts teachers from Finland who implemented and provided feedback on a learning unit framed in those design principles. Teachers implemented a researcher-designed online inquiry unit in nine upper secondary school classrooms. The unit included four 75-minute lessons sequenced to support the location, evaluation, and synthesis of information students encountered in an online inquiry task. Teachers’ diaries revealed their impressions of the unit, problems encountered, and exceptions made to the designed plan. Follow-up interviews revealed additional insights about appropriate time allocation, clear instruction, and areas where students benefit from explicit guidance in strategy use. Findings suggest a researcher-teacher collaboration can be a fruitful endeavor to assist in advancing the design of productive online inquiry activities.
Increasingly, students turn to the internet to seek information to address a problem or complete a learning task. These forms of online inquiry require students to locate relevant and credible information from multiple online resources and build a coherent representation of the explored issue (Leu et al., 2019). Although online inquiry is a common practice, students’ competencies are often under-developed (Brand-Gruwel & van Strien, 2018), resulting in uncritical engagement with online information. Furthermore, many teachers find it challenging to embed instruction of these competencies into their curriculum (Derakhshan & Singh, 2011).
To address these issues, we developed a learning unit designed to intentionally translate relevant theories and design principles into effective classroom practices for teaching online inquiry. Five language arts teachers from Finland collaborated with us to provide initial feedback on the unit; after revisions, they agreed to implement the lessons in nine upper secondary classrooms and reflect on their teaching experiences. In this paper, we describe the theoretical and pedagogical underpinnings of our unit’s design and how it was implemented in classrooms. Then, we share teachers’ reflections about the unit, including ideas for improvements
Digitizing the ‘Ideal’ Latina Information Worker
Get PDFRecent examples of virtual assistant technologies designed as Latina information service workers are noteworthy objects of study for their potential to bridge analyses of Latinas’ labor history and information technology. Latinas in the United States have traditionally worked in blue collar information technology sectors characterized by repetitive labor and low-wages, such as electronics manufacturing and customer service. Latinas information service workers, though fundamental to technoscience, have been largely invisible in histories of computing. Latina virtual assistants mark a shift in this labor history by relying on the strategic visibility of Latina identity in/as the technology interface. Our research explores Latina virtual assistants designed by Airus Media, and installed as airport workers in airports along the southwestern border of the United States. We situate the technocultural narratives present in the design and marketing of these technologies within the broader histories of invisible Latina information labor in the United States. We find continuities between the ways Latinas have historically been positioned as “ideal” information workers, and the use of Latina identity in the design of virtual assistants. We argue that the strategic visibility of Latina virtual assistants is linked to the oppressive structures of invisibility that have traditionally organized Latina information service workers
Operationalizing resilience planning, theory, and practice: Insights from U.S. seaports
Get PDFAcademics and practitioners advocate climate change resilience planning to guide seaport management, business continuity planning, capital improvements, and so forth. Yet, questions of whether resilience planning interventions influence seaports\u27 planning cultures and result in better prepared organizations remain underexplored. Through 10 cases of U.S. seaport resilience planning, this research explored the benefits and challenges of resilience planning and whether such efforts can enhance the adaptive capacity of a complex, multi-layered system such as a seaport. Results suggested that resilience planning interventions enhanced, inter alia, seaports\u27 social capital with their internal and external stakeholders, and that seaports frequently identified and pursued infrastructure-related resilience enhancement strategies after completing resilience planning. Even when the sponsors of such studies intended an operational and business resilience purpose, they stated benefits consistent with adaptive management and resilience planning theories. Further, while key informants emphasized the strengthened relationships with stakeholders as benefits, they also frequently cited them as key challenges that require deliberative guidance and resources to help stakeholders effectively use products from resilience planning. Additional takeaways captured in this research provide valuable insights that can inform guidance materials designed to help seaports undertake their climate resilience-building endeavors