Evaluation and Credentialing in Digital Music Communities

An examination of the use of digital badges as a reward for both casual online music evaluators and professional musicians. Professional and amateur musicians alike use social media as a platform for showcasing and promoting their music. Social media evaluation practices—rating, ranking, voting, “liking,” and “friending” by ordinary users, peers, and critics—have become essential promotional tools for musicians. In this report, H. Cecilia Suhr examines one recent development in online music evaluation: the use of digital badges to aid in assessment and evaluation. Digital badges have emerged in recent years as a potential credentialing method in informal learning environments. Suhr explores online music communities' use of digital badges as a reward for both casual music evaluators and musicians. Suhr examines the intersection of evaluation and gamification in Spotify's “Hit or Not” game, in which players assess a song's hit potential and receive digital badges as rewards, and considers the implications of turning music evaluation into a game. She then explores in detail the development of peer and professional critics on Indaba Music, a cloud-based collaboration platform where musicians earn badges through participating in contests. Suhr considers the emerging challenges and shortcomings of contest-based virtual communities and the value of badges, as perceived by Indaba musicians. She investigates to what extent digital badges can effectively represent and credit musicians' accomplishments and merits; describes the challenges, benefits, and shortcomings of digital badges as an evaluation mechanism; and compares the use of digital badges in assessing creativity to their use in learning and credentialing institutions

Evaluation and Credentialing in Digital Music Communities

An examination of the use of digital badges as a reward for both casual online music evaluators and professional musicians.Professional and amateur musicians alike use social media as a platform for showcasing and promoting their music. Social media evaluation practices—rating, ranking, voting, “liking,” and “friending” by ordinary users, peers, and critics—have become essential promotional tools for musicians. In this report, H. Cecilia Suhr examines one recent development in online music evaluation: the use of digital badges to aid in assessment and evaluation. Digital badges have emerged in recent years as a potential credentialing method in informal learning environments. Suhr explores online music communities' use of digital badges as a reward for both casual music evaluators and musicians.Suhr examines the intersection of evaluation and gamification in Spotify's “Hit or Not” game, in which players assess a song's hit potential and receive digital badges as rewards, and considers the implications of turning music evaluation into a game. She then explores in detail the development of peer and professional critics on Indaba Music, a cloud-based collaboration platform where musicians earn badges through participating in contests. Suhr considers the emerging challenges and shortcomings of contest-based virtual communities and the value of badges, as perceived by Indaba musicians. She investigates to what extent digital badges can effectively represent and credit musicians' accomplishments and merits; describes the challenges, benefits, and shortcomings of digital badges as an evaluation mechanism; and compares the use of digital badges in assessing creativity to their use in learning and credentialing institutions

Influence of Pure Dephasing on Emission Spectra from Single Photon Sources

We investigate the light-matter interaction of a quantum dot with the electromagnetic field in a lossy microcavity and calculate emission spectra for non-zero detuning and dephasing. It is found that dephasing shifts the intensity of the emission peaks for non-zero detuning. We investigate the characteristics of this intensity shifting effect and offer it as an explanation for the non-vanishing emission peaks at the cavity frequency found in recent experimental work.Comment: Published version, minor change

Setting up and modelling of overflowing fed-batch cultures of Bacillus subtilis for the production and continuous removal of lipopeptides

This work is related to the setup of overflowing exponential fed-batch cultures (O-EFBC) derived from carbon limited EFBC dedicated to the production of mycosubtilin, an antifungal lipopeptide belonging to the iturin family. O-EFBC permits the continuous removal of the product from the bioreactor achieving a complete extraction of mycosubtilin. This paper also provides a dynamical Monod-based growth model of this process that is accurate enough to simulate the evolution of the specific growth rate and to correlate it to the mycosubtilin specific productivity. Two particular and dependant phenomena related to the foam overflow are taken into account by the model: the outgoing flow rate of a broth volume and the loss of biomass. Interestingly, the biomass concentration in the foam was found to be lower than the biomass concentration in the bioreactor relating this process to a recycling one. Parameters of this model are the growth yield on substrate and the maximal specific growth rate estimated from experiments led at feed rates of 0.062, 0.071 and 0.086 h --1. The model was extrapolated to five additional experiments carried out at feed rates of 0.008, 0.022, 0.040, 0.042 and 0.062 h --1 enabling the correlation of the mean specific growth rates with productivity results. Finally, a feed rate of 0.086 h --1 corresponding to a mean specific growth rate of 0.070 h --1 allowed a specific productivity of 1.27 mg of mycosubtilin g --1 of dried biomass h --1

Antibubbles - Experimentelle Zugänge

So als hätte man bei einer gewöhnlichen Seifenblase die Materialien Luft und Wasser vertauscht, bestehen Antibubbles aus einer Wasserkugel, die durch eine dünne Luftschicht vom umgebenden Wasser getrennt ist. Diese fragilen, schillernden „Perlen“, die jeder mit etwas Übung herstellen kann, werfen eine Reihe physikalischer Fragen auf, von denen sich einige mit schulischen Mitteln beantworten lassen. Weil die Totalreflexion den Einblick in das Innere der Antibubbles einschränkt, bleibt ihre genaue Beschaffenheit weitgehend im Verborgenen. Dennoch gelingt mit mechanischen und optischen Methoden gewissermaßen ein Blick durchs Schlüsselloch, der Aufschlüsse über ihren Aufbau und ihre Dynamik liefert

Combinatorial sputter synthesis of single-phase La(XYZ)O3±σ_{3\pm\sigma} perovskite thin film libraries: a new platform for materials discovery

Compositionally complex perovskites provide the opportunity to develop stable and active catalysts for electrochemical applications. The challenge lies in the identification of single-phase perovskites with optimized composition for high electrical conductivity. Leveraging a recently discovered effect of self-organized thin film growth during reactive sputtering, La-Co-Mn-O and La-Co-Mn-Fe-O perovskite (ABO3) thin film materials libraries are synthesized. These show phase-pure La-perovskites over a wide range of chemical composition variation for the B-site elements for deposition temperatures equal to or higher than 300$^\circ$C. It is demonstrated that this approach enables the discovery and tailoring of chemical compositions for desired optical bandgap and electrical conductivity, and thereby opens the path for the targeted development of e.g. new high-performance electrocatalysts