Electroslag remelting - Its status, mechanism and refining aspects in the production of quality steels

Electroslag remelting has been established as a new measure for the production of quality steels. Many properties of ESR steels are dramatically superior to those of conventionally produced steels. Majority of inclusions are eliminated during ESR depending on slag composition, temperature and melt rate. Usually, after ESR, the metal does not contain sany inclusion larger than 10-12 mm. The pronounced effect of ESR is a feasible and effective method of further enhancing the ductility and charpy U-notch toughness, with some improvement in strength as a result of refinement. ESR is a convenient and economic route for processing steels and alloys which are otherwise difficult to process

Boomerang: Rebounding the consequences of reputation feedback on crowdsourcing platforms

Paid crowdsourcing platforms suffer from low-quality workand unfair rejections, but paradoxically, most workers and requesters have high reputation scores. These inflated scores, which make high-quality work and workers difficult to find,stem from social pressure to avoid giving negative feedback. We introduce Boomerang, a reputation system for crowdsourcing that elicits more accurate feedback by rebounding the consequences of feedback directly back onto the person who gave it. With Boomerang, requesters find that their highly rated workers gain earliest access to their future tasks, and workers find tasks from their highly-rated requesters at the top of their task feed. Field experiments verify that Boomerang causes both workers and requesters to provide feedback that is more closely aligned with their private opinions. Inspired by a game-theoretic notion of incentive-compatibility, Boomerang opens opportunities for interaction design to incentivize honest reporting over strategic dishonesty

Crowd guilds: Worker-led reputation and feedback on crowdsourcing platforms

Crowd workers are distributed and decentralized. While decentralization is designed to utilize independent judgment to promote high-quality results, it paradoxically undercuts behaviors and institutions that are critical to high-quality work. Reputation is one central example: crowdsourcing systems depend on reputation scores from decentralized workers and requesters, but these scores are notoriously inflated and uninformative. In this paper, we draw inspiration from historical worker guilds (e.g., in the silk trade) to design and implement crowd guilds: centralized groups of crowd workers who collectively certify each other’s quality through double-blind peer assessment. A two-week field experiment compared crowd guilds to a traditional decentralized crowd work model. Crowd guilds produced reputation signals more strongly correlated with ground-truth worker quality than signals available on current crowd working platforms, and more accurate than in the traditional model

The Daemo crowdsourcing marketplace

The success of crowdsourcing markets is dependent on a strong foundation of trust between workers and requesters. In current marketplaces, workers and requesters are often unable to trust each other’s quality, and their mental models of tasks are misaligned due to ambiguous instructions or confusing edge cases. This breakdown of trust typically arises from (1) flawed reputation systems which do not accurately reflect worker and requester quality, and from (2) poorly designed tasks. In this demo, we present how Boomerang and Prototype Tasks, the fundamental building blocks of the Daemo crowdsourcing marketplace, help restore trust between workers and requesters. Daemo’s Boomerang reputation system incentivizes alignment between opinion and ratings by determining the likelihood that workers and requesters will work together in the future based on how they rate each other. Daemo’s Prototype tasks require that new tasks go through a feedback iteration phase with a small number of workers so that requesters can revise their instructions and task designs before launch

Prototype tasks: Improving crowdsourcing results through rapid, iterative task design

Low-quality results have been a long-standing problem on microtask crowdsourcing platforms, driving away requesters and justifying low wages for workers. To date, workers have been blamed for low-quality results: they are said to make as little effort as possible, do not pay attention to detail, and lack expertise. In this paper, we hypothesize that requesters may also be responsible for low-quality work: they launch unclear task designs that confuse even earnest workers, under-specify edge cases, and neglect to include examples. We introduce prototype tasks, a crowdsourcing strategy requiring all new task designs to launch a small number of sample tasks. Workers attempt these tasks and leave feedback, enabling the requester to iterate on the design before publishing it. We report a field experiment in which tasks that underwent prototype task iteration produced higher-quality work results than the original task designs. With this research, we suggest that a simple and rapid iteration cycle can improve crowd work, and we provide empirical evidence that requester “quality” directly impacts result quality

Polymerase-directed synthesis of C5-ethynyl locked nucleic acids

Modified nucleic acids have considerable potential in nanobiotechnology for the development of nanomedicines and new materials. Locked nucleic acid (LNA) is one of the most prominent nucleic acid analogues reported so far and we herein for the first time report the enzymatic incorporation of LNA-U and C5-ethynyl LNA-U nucleotides into oligonucleotides. Phusion High Fidelity and KOD DNA polymerases efficiently incorporated LNA-U and C5-ethynyl LNA-U nucleotides into a DNA strand and T7 RNA polymerase successfully accepted the LNA-U nucleoside 5′-triphosphate as substrate for RNA transcripts

Improved specificity of gene silencing by siRNAs containing unlocked nucleobase analogs

siRNAs confer sequence specific and robust silencing of mRNA. By virtue of these properties, siRNAs have become therapeutic candidates for disease intervention. However, their use as therapeutic agents can be hampered by unintended off-target effects by either or both strands of the siRNA duplex. We report here that unlocked nucleobase analogs (UNAs) confer desirable properties to siRNAs. Addition of a single UNA at the 5′-terminus of the passenger strand blocks participation of the passenger strand in RISC-mediated target down-regulation with a concomitant increase in guide strand activity. Placement of a UNA in the seed region of the guide strand prevents miRNA-like off-target silencing without compromising siRNA activity. Most significantly, combined substitution of UNA at the 3′-termini of both strands, the addition of a UNA at the 5′-terminus of the passenger strand, and a single UNA in the seed region of the guide strand, reduced the global off-target events by more than 10-fold compared to unmodified siRNA. The reduction in off-target events was specific to UNA placement in the siRNA, with no apparent new off-target events. Taken together, these results indicate that when strategically placed, UNA substitutions have important implications for the design of safe and effective siRNA-based therapeutics

‘We Learn Together’—Translanguaging within a Holistic Approach towards Multilingualism in Education

Within two multilingual education projects in the north of the Netherlands a holistic model for multilingualism in education is being tested. This is done through design-based interventions in which in- and pre-service teachers, teacher trainers and researchers co-develop and evaluate multilingual activities for different school types. Results show that through experimenting in a safe environment teachers gradually embraced their pupils’ multilingualism. This contradicts earlier findings on teachers strongly favouring monolingual instruction and viewing migrant languages as a deficit.<br/