A primary goal of biomedical research is to elucidate molecular mechanisms, particularly those responsible for human traits, either normal or pathological. Yet achieving this goal is difficult if not ...impossible when the traits of interest lack tractable models and so cannot be dissected through time‐honoured approaches like forward genetics or reconstitution. Arguably, no biological problem has hindered scientific progress more than this: the inability to dissect a trait's mechanism without a tractable likeness of the trait. At root, forward genetics and reconstitution are powerful approaches because they assay for specific molecular functions. Here, we discuss an alternative way to uncover important mechanistic interactions, namely, to assay for positive natural selection. If an interaction has been selected for, then it must perform an important function, a function that significantly promotes reproductive success. Accordingly, selection is a consequence and indicator of function, and uncovering multimolecular selection will reveal important functional interactions. We propose a selection signature for interactions and review recent selection‐based approaches through which to dissect traits that are not inherently tractable. The review includes proof‐of‐principle studies in which important interactions were uncovered by screening for selection. In sum, screens for selection appear feasible when screens for specific functions are not. Selection screens thus constitute a novel tool through which to reveal the mechanisms that shape the fates of organisms.
This review examines a new, useful scientific tool—the selection‐signature screen. It summarizes recent selection‐based approaches for dissecting traits that are not inherently tractable. The review includes proof‐of‐principle studies in which important interactions were uncovered by screening for selection. In sum, screens for selection appear feasible when screens for specific functions are not. This tool should facilitate the elucidation of traits unique to mammals or other organisms difficult to study.
Background
Screen‐sharing technologies enable applications such as screen mirroring, video streaming and instant messaging across multiple device screens. Despite their increasing use in many ...contemporary classrooms, there is a paucity of research directly examining pedagogical benefits and issues of these technologies.
Objectives
This study investigated the influence of screen‐sharing technologies on teachers' practices, highlighting pedagogical benefits and issues encountered.
Methods
The paper drew on a sample of 321 K‐12 teachers and utilised principal components analysis, descriptive statistics and inductive coding.
Results and Conclusions
Teachers reported greater mobility, increased ease of content sharing and deeper learner cognition as attributes of improved learning and teaching with the technologies. However, a minority highlighted technical issues such as network and hardware problems affecting their confidence. Despite increased mobility as an affordance, teachers' perceptions about mobility largely appeared to be predicated on assumptions that the technologies were intended for didactic instruction.
Takeaways
The study contributes to a more nuanced understanding of screen‐sharing affordances while underscoring learner‐led screensharing as a focus for future research and practice.
Lay Description
What is already known about this topic
Screen‐sharing technologies are becoming commonplace in many contemporary educational settings.
The technologies represent integrated systems that enable functions such as mirroring, video streaming, online polls, real‐time editing, screen‐capturing and learner analytics.
Screen‐sharing is indirectly examined in several studies with findings indicating improvements in group awareness, emotional engagement, learner confidence to share ideas and teachers' visualization of concepts.
Existing findings are largely anecdotal and there are very few studies that have focused directly on screen‐sharing affordances.
What this paper adds
An empirical study directly examining teachers' first‐hand perspectives of using screen‐sharing technologies.
Benefits relate to greater task focus, deeper thinking, improvements to teaching practice and ease of sharing content.
A minority of teachers experienced issues such as technical problems, inappropriate sharing and distraction.
Mobility was recognized as a key affordance though remained underutilized by many teachers.
Implications for practice and/or policy
Professional learning accompanying the use of screen‐sharing technologies can support teachers to take advantage of all features of screen sharing such as enhanced teacher mobility.
Institutions need to provide requisite technical and professional support for teachers to effectively and reliably leverage screen‐sharing in the classroom.
There is a need to explore teacher's and learner's screen‐sharing uses in situ to more fully understand issues and possibilities.
Mental imagery is a foundational human faculty that depends on active image construction and sensorimotor experiences. However, children now spend a significant proportion of their day engaged with ...screen‐media, which (a) provide them with ready‐made mental images, and (b) constitute a sensory narrowing whereby input is typically focused on the visual and auditory modalities. Accordingly, we test the idea that screen‐time influences the development of children's mental imagery with a focus on mental image generation and inspection from the visual and haptic domains. In a longitudinal cross‐lagged panel design, children (n = 266) aged between 3 and 9 years were tested at two points in time, 10 months apart. Measures of screen‐time and mental imagery were employed, alongside a host of control variables including working memory, vocabulary, demographics, device ownership, and age of exposure to screen‐media. Findings indicate a statistically significant path from screen‐time at time 1 to mental imagery at time 2, above and beyond the influence of the control variables. These unique findings are discussed in terms of the influence of screen‐time on mental imagery.
Mental imagery involves the inner assembly of external experiences and events, to then behold these in front of our ‘inner eye’. Screen‐media do much of this work for us by providing us with ready‐made images. Accordlingy, children who spend more time with screens show reduced mental imagery performance.
We aimed to explore the potential associations between screen use while eating and intuitive eating and disordered (thinness-oriented and muscularity-oriented) eating behaviors.
Analyses included 600 ...Chinese adults (50% women; M
= 30.67, SD = 8.08) recruited online. The use of four major screen devices was captured, including cell phones, tablets, computers, and TVs. Three types of eating behaviors were examined, namely intuitive eating, thinness-oriented disordered eating, and muscularity-oriented disordered eating. Pearson correlation and hierarchical regression analyses were conducted separately for men and women to examine the sex-specific associations between screen use while eating and intuitive eating, thinness-oriented disordered eating, and muscularity-oriented disordered eating.
In both men and women, more screen use while eating was significantly associated with lower intuitive eating, higher thinness-oriented disordered eating, and higher muscularity-oriented disordered eating, above and beyond total screen time and social media use.
We found preliminary evidence for the significant links between screen use while eating and intuitive eating and disordered eating. Given the global increases in screen use, continued research is warranted to further explore the role of screen use while eating in the development and maintenance of intuitive eating and disordered eating.
Much remains unknown regarding screen use while eating and eating behaviors. We found that in both Chinese men and women, more screen use while eating was significantly and uniquely associated with lower intuitive eating, higher thinness-oriented disordered eating, and higher muscularity-oriented disordered eating. Findings highlight the importance of incorporating screen use while eating in future research on intuitive eating and disordered eating.
A screen content coding (SCC) extension to High Efficiency Video Coding (HEVC) is currently under development by the Joint Collaborative Team on Video Coding, which is a joint effort from the ITU-T ...Video Coding Experts Group and the ISO/IEC Moving Picture Experts Group. The main goal of the HEVC-SCC standardization effort is to enable significantly improved compression performance for videos containing a substantial amount of still or moving rendered graphics, text, and animation rather than, or in addition to, camera-captured content. This paper provides an overview of the technical features and characteristics of the current HEVC-SCC test model and related coding tools, including intra-block copy, palette mode, adaptive color transform, and adaptive motion vector resolution. The performance of the SCC extension is compared against existing standards in terms of bitrate savings at equal distortion.
Screen printing technology is a widely used technique for the fabrication of electrochemical sensors. This methodology is likely to underpin the progressive drive towards miniaturized, sensitive and ...portable devices, and has already established its route from "lab-to-market" for a plethora of sensors. The application of these sensors for analysis of environmental samples has been the major focus of research in this field. As a consequence, this work will focus on recent important advances in the design and fabrication of disposable screen printed sensors for the electrochemical detection of environmental contaminants. Special emphasis is given on sensor fabrication methodology, operating details and performance characteristics for environmental applications.
Flatbed screen printing is the dominating process in industry for metallization of silicon solar cells. It offers high throughput rates, high flexibility of printing pattern, and an overall very ...cost-effective production compared with other printing technologies. However, the ongoing demand for an optimization of printed silver electrode shape creates an increasing challenge to paste and screen development. The recent trend of so called "knotless" screens with a screen angle of 0° offers an increased paste transfer, therefore, better electrode conductivity, which leads to an improved solar cell efficiency. The disadvantage of this screen architecture is a reduced screen lifetime and low production yield. This article presents a systematic simulation of screen pattern to investigate screen angles, which allow for an improved knotless screen architecture. Therefore, different types of wire crossings have been defined, simulated, and experimentally verified by microscope images. For example, when 14.036°, 18.435°, and 26.565° are used, knotless screen pattern openings emerge without showing any of the disadvantages of regular 0°-knotless screens. For this reason, statistical screen lifetime estimations are carried out by modeling the intersection lengths of all mesh wires and the emulsion edge across the screen opening. Furthermore, a detailed analysis on manufacturing tolerances is given, showing that the 26.565° screen angle offers the best compromise between challenges during manufacturing and potential performance in production of Si-solar cells.
CRISPR-Cas9 genome engineering has increased the pace of discovery for immunology and cancer biology, revealing potential therapeutic targets and providing insight into mechanisms underlying ...resistance to immunotherapy. However, endogenous immune recognition of Cas9 has limited the applicability of CRISPR technologies in vivo. Here, we characterized immune responses against Cas9 and other expressed CRISPR vector components that cause antigen-specific tumor rejection in several mouse cancer models. To avoid unwanted immune recognition, we designed a lentiviral vector system that allowed selective CRISPR antigen removal (SCAR) from tumor cells. The SCAR system reversed immune-mediated rejection of CRISPR-modified tumor cells in vivo and enabled high-throughput genetic screens in previously intractable models. A pooled in vivo screen using SCAR in a CRISPR-antigen-sensitive renal cell carcinoma revealed resistance pathways associated with autophagy and major histocompatibility complex class I (MHC class I) expression. Thus, SCAR presents a resource that enables CRISPR-based studies of tumor-immune interactions and prevents unwanted immune recognition of genetically engineered cells, with implications for clinical applications.
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•CRISPR vector components are immunogenic and cause rejection in mouse cancer models•The SCAR vector system allows removal of immunogens from CRISPR-edited cells•SCAR enables in vivo screening of antigen-sensitive cell lines•Renal cell carcinoma requires autophagy and MHC class I expression for immune evasion
Dubrot et al. present the design of a scalable CRISPR vector system that removes Cas9 and other antigens after genome editing. They perform an in vivo genetic screen for immunotherapy dependencies in a murine renal cancer model that is sensitive to vector antigen expression.
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