Liquid-infiltrated photonic crystals: Ohmic dissipation and broadening of modes

The pronounced light-matter interactions in photonic crystals make them interesting as opto-fludic "building blocks" for lab-on-a-chip applications. We show how conducting electrolytes cause dissipation and smearing of the density-of-states, thus altering decay dynamics of excited bio-molecules dissolved in the electrolyte. Likewise, we find spatial damping of propagating modes, of the order dB/cm, for naturally occurring electrolytes such as drinking water or physiological salt water.Comment: 9 pages including 2 figure

Server-Driven Scheduling for Scalable and Collision-Free LoRaWAN Networks

This project explores server-driven time-based scheduling protocolsfor LoRaWAN networks composed of devices that transmit periodically.The aim is to eliminate collisions and improve channel utilizationby assigning time slots to devices according to a collision-freeschedule. Three scheduling protocols are introduced, each with differentapproaches to slot assignment and rescheduling. A customsimulator is used to evaluate their performance under varying networkdensities and device periodicities.Results show that all three protocols can maintain close to 100%utilization of available time slots under periodic traffic patterns,provided that drift correction and rescheduling are managed correctly.The project focuses on single-channel, single-spreading factorLoRaWAN scenario, but the proposed scheduling structure is designedto be extensible to more complex deployments. The findingshighlight the importance of slot structuring, rescheduling strategies,and drift management in achieving reliable operation at scale in Lo-RaWAN systems.This project explores server-driven time-based scheduling protocolsfor LoRaWAN networks composed of devices that transmit periodically.The aim is to eliminate collisions and improve channel utilizationby assigning time slots to devices according to a collision-freeschedule. Three scheduling protocols are introduced, each with differentapproaches to slot assignment and rescheduling. A customsimulator is used to evaluate their performance under varying networkdensities and device periodicities.Results show that all three protocols can maintain close to 100%utilization of available time slots under periodic traffic patterns,provided that drift correction and rescheduling are managed correctly.The project focuses on single-channel, single-spreading factorLoRaWAN scenario, but the proposed scheduling structure is designedto be extensible to more complex deployments. The findingshighlight the importance of slot structuring, rescheduling strategies,and drift management in achieving reliable operation at scale in Lo-RaWAN systems

Kritisk-æstetiske scenarier i teknologiforståelse – en tværfaglig tilgang

Denne artikel belyser, om og hvordan kritisk-æstetiske scenarier kan udvikle det danske teknologiforståelsesfagfelts fagdidaktik i forløb med alle fire kompetenceområder i spil. Artiklens hypotese er, at sådanne scenarier er egnet til at udvikle elevernes kritiske sans og dermed den digitale myndiggørelse, fordi de kan stimulere elevernes evne til at for­lade deres egen position og dermed kritisk forholde sig til sagen gennem processer, hvor de arbejder med materialiseringer af forestillinger om teknologi og konsekvenser af teknologianvendelse. Inspireret af design-based research tager undersøgelsen udgangs­punkt i et undervisningsforløb, hvor en 6. klasse skulle udvikle digitale artefakter, der kritisk udstiller samfundets brug af sundhedsdata. I første del designede eleverne et dødsur, der forudsiger en persons dødsdato, og i anden del designede de en prototype af et sundhedsprogram målrettet en kunde i én af tre cases: en totalitær stat, et super­sygehus eller elevernes egen virksomhed. Empiri blev indsamlet ved hjælp af obser­vationer og uformelle samtaler i undervisningen samt interviews med læreren og ana­lyseres med fokus på det potentielle læringspotentiale, det aktualiserede lærings­potentiale og faktisk læring. Analysen afdækker et stort potentielt læringspotentiale, som kun i nogen grad aktualiseres i den konkrete undervisning, som igen kun fører til begrænset relevant faktisk læring hos eleverne. Analysen diskuteres med artiklens teoretiske ståsted og erfaringer fra forsøgsfaget teknologiforståelse i et forsøg på at kvalificere fremtidige forløb baseret på kritisk-æstetiske scenarier i fagfeltet.</jats:p

Citizen Media and Public Spaces:Diverse Expressions of Citizenship and Dissent

Citizen Media and Public Spaces presents a pioneering exploration of citizen media as a highly interdisciplinary domain that raises vital political, social and ethical issues relating to conceptions of citizenship and state boundaries, the construction of publics and social imaginaries, processes of co-optation and reverse co-optation, power and resistance, the ethics of witnessing and solidarity, and novel responses to the democratic deficit. Framed by a substantial introduction by the editors, the twelve contributions to the volume interrogate the concept of citizen media theoretically and empirically, and offer detailed case studies that extend from the UK to Russia and Bulgaria and from China to Denmark and the liminal spaces within which a growing number of refugees now live. A rich new domain of scholarship and practice emerges out of the studies presented. Citizen media is shown to embrace both physical and digital interventions in public space, as well as the sets of values and agendas that influence and drive the practices and discourses through which individuals and collectives position themselves within and in relation to society and participate in the creation of diverse publics

Activity of dietary fatty acids on FFA1 and FFA4 and characterisation of pinolenic acid as a dual FFA1/FFA4 agonist with potential effect against metabolic diseases

Various foods are associated with effects against metabolic diseases such as insulin resistance and type 2 diabetes; however, their mechanisms of action are mostly unclear. Fatty acids may contribute by acting as precursors of signalling molecules or by direct activity on receptors. The medium- and long-chain NEFA receptor FFA1 (free fatty acid receptor 1, previously known as GPR40) has been linked to enhancement of glucose-stimulated insulin secretion, whereas FFA4 (free fatty acid receptor 4, previously known as GPR120) has been associated with insulin-sensitising and anti-inflammatory effects, and both receptors are reported to protect pancreatic islets and promote secretion of appetite and glucose-regulating hormones. Hypothesising that FFA1 and FFA4 mediate therapeutic effects of dietary components, we screened a broad selection of NEFA on FFA1 and FFA4 and characterised active compounds in concentration–response curves. Of the screened compounds, pinolenic acid, a constituent of pine nut oil, was identified as a relatively potent and efficacious dual FFA1/FFA4 agonist, and its suitability for further studies was confirmed by additional in vitro characterisation. Pine nut oil and free and esterified pure pinolenic acid were tested in an acute glucose tolerance test in mice. Pine nut oil showed a moderately but significantly improved glucose tolerance compared with maize oil. Pure pinolenic acid or ethyl ester gave robust and highly significant improvements of glucose tolerance. In conclusion, the present results indicate that pinolenic acid is a comparatively potent and efficacious dual FFA1/FFA4 agonist that exerts antidiabetic effects in an acute mouse model. The compound thus deserves attention as a potential active dietary ingredient to prevent or counteract metabolic diseases