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Climate change is likely to threaten the livelihood of millions of smallholder farmers in Sub-Saharan Africa and elsewhere. This paper investigates whether cooperatives could play a role in promoting climate adaptation among their members and, through spillover-effects on non-members in their villages, among their communities at large. For this purpose, we use panel data collected among smallholder farm households in Ethiopia. We find that (i) cooperative membership increases the number of adaptation practices adopted by farm households; (ii) this effect increases with the number of cooperatives of which farm households are members, and (iii) non-members in villages with cooperatives adopt more adaptation practices than farm households in villages without cooperatives, although results are statistically significant only for certain types of cooperatives. These results suggest that considering different levels at which climate change adaptation takes place should receive greater attention among researchers and policymakers. For example, enhancing the institutional capacity of and creating partnerships with cooperatives could facilitate the implementation of climate change adaptation policies and strategies, including at the farm level.

Fjernelsen af nitrat i et ådalsmagasin afhænger af fordelingen af treparametre i ådalsmagasinet: reduktionskapacitet, nedbrydningsrate,og vandets opholdstid. Er der sammenhæng mellem naturskønhedog effektiv nitratfjernelse? Kan effektiv nitratfjernelse ses?

The sustainable use of wildlife is a core aspiration of multi-lateral conservation policy but is the subject to intense debate in the scientific literature. We use a global data set of over 11,000 population time-series to derive indices of ‘used’ and ‘unused’ species and assess global and regional changes in wildlife populations – principally for mammals, birds and fishes. We also assess whether ‘management’ makes a measurable difference to wildlife population trends, especially for the used species populations. Our results show that wildlife population trends globally are negative, but with used populations tending to decline more rapidly, especially in Africa and the Americas. Crucially, where used populations are managed, using a variety of mechanisms, there is a positive impact on the trend. It is therefore true that use of species can both be a driver of negative population trends, or a driver of species recovery, with numerous species and population specific case examples making up these broader trends. This work is relevant to the evidence base for the IPBES Sustainable Use Assessment, and to the development of indicators of sustainable use of species under the post-2020 Global Biodiversity Framework being developed under the Convention on Biological Diversity.

Anthropogenic stressors threaten the largest source of freshwater to humankind – groundwater – and all subterranean ecosystems. These are widespread in the subsurface all around the globe, and they harbour a uniquely specialized fauna responsible for valuable ecosystem services. The restricted access to the underground challenges obtaining knowledge about the functioning of subterranean ecosystems, thereby precluding the development of appropriate assessment tools to evaluate the impacts of anthropogenic stressors on subterranean organisms. This thesis is a contribution to the study of the impacts of anthropogenic disturbance in subterranean ecosystems. It examines the state of the art and discusses the future perspectives of the ecotoxicological effects of anthropogenic stressors on subterranean organisms. It studies the sensitivity of a widespread groundwater copepod to different contaminants. Develops a novel protocol for acute in situ ecotoxicity test using native crustaceans applied to groundwater ecosystems, which was subsequently used in a comparative test of the sensitivity of subterranean vs surface organisms, on a phylogenetically controlled experiment. Finally, the thesis presents a case study of environmental risk assessment of the effects of groundwater salinization and global warming on the groundwater-adapted fauna from arid and semi-arid regions. The results show that anthropogenic stressors clearly pose a risk to the ecological integrity of subterranean ecosystems. The sensitivity of a widespread groundwater copepod was found to be compound-specific, and the copepod responded similarly to previously tested groundwater-adapted animals, all more tolerant than the surface-living species. The novel acute in situ protocol provides a reliable alternative to standard laboratory testing, and allows the use of native species under realistic scenarios. This made it possible to test that the ecosystem type and local environmental conditions (as electrical conductivity of water) play a significant role in determining the sensitivity of closely related surface vs. subterranean species. This thesis also provides evidences that increasing salinity and temperature pose a risk to groundwater ecosystems, especially in dry regions.Overall, this thesis shows that anthropogenic disturbances critically affect subterranean ecosystems, and interdisciplinary research is needed to ensure their safeguarding and sustainability.

Given an elliptic curve E defined over Q which has potential complex multiplication by the ring of integers OK of an imaginary quadratic field K we construct a polynomial PE∈Z[x,y] which is a planar model of E and such that the Mahler measure m(PE)∈R is related to the special value of the L-function L(E,s) at s=2.

Afhandlingen undersøger det danske filmkomikerpar Fy og Bi som et transnationalt filmfænomen i 1920’erne og 1930’ernes filmkultur. Fra 1921 til 1940 blev der produceret 48 film med Fy og Bi; størstedelen af disse af produktionsselskabet Palladium, hvor instruktøren Lau Lauritzen i 1921etablerede duoen. Sideløbende blev de to skuespillere bag, Carl Schenstrøm og Harald Madsen, udlånt til udenlandske filmselskaber, der også iscenesatte Fy og Bi-film. Filmene nød stor og bred international succes, men nogen større akademisk forskningsindsats i dette kapitel af dansk stum og tidlig tonefilm har ikke tidligere været foretaget.Den overordnede filmhistoriske tilgang tager afsæt i New Cinema History, hvorsociokulturelle forhold omkring distribution og filmfremvisning søges afdækket empirisk og kildenært. Denne metodologiske praksis centrerer sig i særlig grad omkring kilder som aviser og branchepublikationer. Gennem en detaljeret undersøgelse af kildemateriale som dette, udforskes og kortlægges produktions- og distributionsforhold, samarbejdspartnere og fremvisningspraksis i relation til Fy og Bis grænsekrydsende aktiviteter. I analysen af, hvorledes filmene med Fy og Bi nåede så langt ud over de danske grænser, inddrages en række anskuelsesvinkler i afhandlingen.Først indskrives etableringen af Palladium – dette oprindeligt som et svensk selskab på dansk grund – i relation til den øvrige, danske filmbranche omkring 1920. Da Palladium i 1923 indgik samarbejde med en engelsk filmagent, Arthur G. Gregory, og en tysk distributør og producent, Lothar Stark, tog selskabets udenlandske succes fart. Gennem afdækningen af disse hidtil oversete aktørers roller; både i relation til Palladium og Fy og Bi samt den øvrige filmbranche, bidrager afhandlingen med ny viden og filmhistorien nuanceres. Derefter kortlægges de i alt tretten udenlandske filmproduktioner, som Schenstrøm og Madsen medvirkede i som Fy og Bi for selskaber i Sverige, Østrig, England, Tyskland og Ungarn i årene mellem 1925 og 1937.Palladiums forhandlinger med det pan-europæiske filmkonsortium Westi-Film, hvor Gregory i en periode også var ansat, afdækkes i detaljen. Her var det planlagt, at Fy og Bi skulle tilknyttes, men Starks mellemkomst og Westis kollaps i 1925 satte en stopper for dette. Distributions- og fremvisningsmønstret af film med Fy og Bi i München er det case-baserede omdrejningspunkt for afhandlingens følgende kapitel, hvor duoens udbredelse analyseres gennem en kortlægning af biografernes repertoire i årene mellem 1924-1934. Her opnåede mindst 36 ud af de i alt 41 Fy og Bi-film, der blev produceret i perioden, fremvisning i München. Fy og Bi var faste og genkommende skikkelser på byens biograflærreder. Ikke bare i München, men også i det øvrige Tyskland, hvor deres film blev stemt ind blandt biografejernes største kassesucceser i årligerundspørger i sidste halvdel af 1920’erne. Endelig afdækkes forhold knyttet til den vidtforgrenede promoveringsindsats af Fy og Bi i form af personlige optrædener, reklamer, facadeudsmykning, merchandise og tie-ins, mens retssager om duoens tyske navneophav og omrejsende Fy og Bi falsknereunderstreger, hvordan fænomenet Fy og Bi også blev forsøgt udnyttet i kommercielt øjemed af flere forskellige aktører.På baggrund af ovenstående undersøgelser af Palladiums vigtigste samarbejdspartnere og disses sammenfiltrede forretningsforhold, udenlandske Fy og Bi-produktioner, den case-baserede udforskning af filmenes distribution og fremvisningsmønster i München, forskelligartede udtryk for markedsføringspraksis og afledte effekter af denne, tydeliggør afhandlingen årsagen til Fy og Bis succes, idet den peger på den danske filmduo som et udpræget transnationalt filmfænomen.Nøgleord: filmhistorie, Palladium, Fy og Bi, New Cinema History, filmhistoriografi, stumfilm,transnational film, entangled history.

Mobile crowd sensing (MCS) has emerged as an increasingly popular sensing paradigm due to its cost-effectiveness. This approach relies on platforms to outsource tasks to participating workers when prompted by task publishers. Although incentive mechanisms have been devised to foster widespread participation in MCS, most of them focus only on static tasks (i.e., tasks for which the timing and type are known in advance) and do not protect the privacy of worker bids. In a dynamic and resource-constrained environment, tasks are often uncertain (i.e., the platform lacks a priori knowledge about the tasks) and worker bids may be vulnerable to inference attacks. This paper presents HERALD*, an incentive mechanism that addresses these issues through the use of uncertainty and hidden bids. Theoretical analysis reveals that HERALD* satisfies a range of critical criteria, including truthfulness, individual rationality, differential privacy, low computational complexity, and low social cost. These properties are then corroborated through a series of evaluations.

We decompose changing gaps in life expectancy between rich and poor into differential changes in age-specific mortality rates and differences in "survivability". Declining age-specific mortality rates increases life expectancy, but the gain is small if the likelihood of living to this age is small (ex ante survivability) or if the expected remaining lifetime is short (ex post survivability). Lower survivability of the poor explains half of the recent rise in life expectancy inequality in the US and the entire rise in Denmark. Cardiovascular mortality declines favored the poor, but differences in lifestyle-related survivability led inequality to rise.