The method by which Cephenemyia trompe (Modeer) larvae invade reindeer (Rangifer tarandus)

Laboratory electrostimulated C. trompe (Modeer) females forcefully expelled (sprayed) larvae for 5-20 cm. The watery spray consisted of about 20 tiny droplets containing two to several larvae. Crawling first-instar larvae exhibited negative geotactic and phototropic responses; they were subject to rapid desiccation and became immobile as the tiny droplets dried within a few seconds. When 5-50 larvae from dissectedfemales were dropped in physiological saline onto different areas of the muzzle of restrained reindeer, only larvae placed deep within the nostrils and on the lips crawled out-of-sight down the nostril passage or into the mouth. Drops of larvae placed elsewhere quickly desiccated and the larvae became immobile. Larvae deposited by wild females onto a COz-baited reindeer model with the muzzle, lips and nostrils coated with insect trapping adhesive all were stuck only along the dorsal lip below the philtrum. All experimental evidence supports a natural per os mode of invasion

The mating sites of the reindeer nose bot fly: not a practical target for control

The reindeer nose bot fly Cephenemyia trompe aggregates on hilltops/mountaintops to mate. Although active only for brief periods on certain days, males have been collected only from such sites. To evaluate possible suppression of the fly population by killing males (by insecticides or traps) at such sites, the density of sites and the number of males at each site were monitored in a summer grazing area of the semidomestic reindeer host (Rangifer tarandus) in Finnmark, northern Norway. In an area of ca. 20 km2, 19 mating sites were detected and examined during 4 hours on one day. The number of males observed at most sites was 5-16 (range 3-60). Minor hilltops had few males but at some sites >20-60 flies were dispersed over an area of at least 100 m2. It is concluded that mating sites in the study area are too numerous, and also used by many beneficial non-target species, to be practical targets for control of the species

Reinens hud- og svelgbrems (Oedemagena tarandi L. og Cephenemyia trompe Modeer), økologi og atferd

Dette forskningsprosjektet på de økonomisk viktige artene for reindriften startet i 1983. Prosjektet er et internasjonalt samarbeid mellom forfatterne og med Økologisk Avdeling ved Universitetet i Tromsø under ledelse av professor Odd Halvorsen. Siktemålet med forskningen er å skaffe grunnleggende kunnskaper om disse to bremseartenes biologi, adferd, fysiologi og epidemiologi. Det ligger videre anvendte perspektiver, især når det gjelder mulighetene for biologisk kontroll, til grunn for prosjektet. Utviklingsfondet for reindrift og Universitetet i Tromsø har støttet prosjektet økonomisk. Feltarbeidet har i hovedsak foregått i Vest¬Finnmark

Nordic NATO in transition: Toward turbulence in the 1990s?

Arms Control & Domestic and International Security (ACDIS

Editorial: The Impact of AI-Enabled Technologies in E-commerce and Omnichannel Retailing

[No abstract available

Multiphysics 3D modelling of ironless permanent magnet generators

Analytical method is widely used for the preliminary design and optimization of electrical machines. It has short calculation time and low computational cost (cost of simulation codes and supporting hardware), but the calculate result is normally considered to be not as accurate as finite element method (FEM). On the other hand, it is time-consuming to optimize machines with FEM if the optimization is not parallelized. Parallelizing optimization requires many licenses when commercial FEM codes are used, which can be very expensive. Ironless permanent magnet generator has large diameter and small aspect ratio, therefore, multiphysics approach is expected to be used for investigating the magnetic and thermal field. To address the above challenges, this paper presents a multiphysics modelling strategy for the design and optimization of ironless permanent magnet generators. Open-source codes are used to reduce the computational cost. A design example is presented to demonstrate the detail of this design method. This approach is expected to be used in super computer in the future, so that the calculation time can be largely reduced

Thermodynamic Properties near the onset of Loop-Current Order in high-TcT_c superconducting cuprates

We have performed large-scale Monte Carlo simulations on a two-dimensional generalized Ashkin-Teller model to calculate the thermodynamic properties in the critical region near its transitions. The Ashkin-Teller model has a pair of Ising spins at each site which interact with neighboring spins through pair-wise and 4-spin interactions. The model represents the interactions between orbital current loops in $Cu O_2$-plaquettes of high-$T_c$ cuprates, which order with a staggered magnetization \Mso inside each unit-cell in the underdoped region of the phase diagram below a temperature $T^*(x)$ which depends on doping. The pair of Ising spins per unit-cell represent the directions of the currents in the links of the current loops. The generalizations are the inclusion of anisotropy in the pair-wise nearest neighbor current-current couplings consistent with the symmetries of a square lattice and the next nearest neighbor pair-wise couplings. We use the Binder cumulant to estimate the correlation length exponent $\nu$ and the order parameter exponent $\beta$. Our principal results are that in a range of parameters, the Ashkin-Teller model as well as its generalization has an order parameter susceptibility which diverges as $T \to T^*$ and an order parameter below $T^*$. Importantly, however, there is no divergence in the specific heat. This puts the properties of the model in accord with the experimental results in the underdoped cuprates. We also calculate the magnitude of the "bump" in the specific heat in the critical region to put limits on its observability. Finally, we show that the staggered magnetization couples to the uniform magnetization $M_0$ such that the latter has a weak singularity at $T^*$ and also displays a wide critical region, also in accord with recent experiments.Comment: 14 pages, 19 figures, to appear in Physical Review

Spatiotemporal dynamics in a spatial plankton system

In this paper, we investigate the complex dynamics of a spatial plankton-fish system with Holling type III functional responses. We have carried out the analytical study for both one and two dimensional system in details and found out a condition for diffusive instability of a locally stable equilibrium. Furthermore, we present a theoretical analysis of processes of pattern formation that involves organism distribution and their interaction of spatially distributed population with local diffusion. The results of numerical simulations reveal that, on increasing the value of the fish predation rates, the sequences spots $\rightarrow$ spot-stripe mixtures$\rightarrow$ stripes$\rightarrow$ hole-stripe mixtures holes$\rightarrow$ wave pattern is observed. Our study shows that the spatially extended model system has not only more complex dynamic patterns in the space, but also has spiral waves.Comment: Published Pape

Hybridization of Atlantic puffins in the Arctic coincides with 20th-century climate change

The Arctic is experiencingthe fastest rates of globalwarming,leadingto shiftsin the distributionof its biotaandincreasingthe potentialfor hybridization. However, genomicevidenceof recenthybridization events in theArctic remainsunexpectedlyrare. Here, we use whole-genomesequencingof contemporary and 122-year-oldhistoricalspecimensto investigate the originof an Arctic hybridpopulation of Atlanticpuffins(Fr aterculaarctica)on Bjørnøya, Norway. We show that the hybridization between the High Arctic, large-bodiedsubspeciesF. a. naumanniand the temperate, smaller-sizedsubspeciesF. a. arcticabeganas recentlyas six generationsagodue to an unexpectedsouthward rangeexpansionofF. a. naumanni.Moreover, we find a significanttemporalloss of geneticdiversityacross Arctic and temperate puffinpopulations.Our observationsprovide compellinggenomicevidenceof the impacts of recentdistributionalshiftsand loss of diversityin Arctic communitiesduringthe 20th century.publishedVersio

Coffee bean extracts rich and poor in kahweol both give rise to elevation of liver enzymes in healthy volunteers

BACKGROUND: Coffee oil potently raises serum cholesterol levels in humans. The diterpenes cafestol and kahweol are responsible for this elevation. Coffee oil also causes elevation of liver enzyme levels in serum. It has been suggested that cafestol is mainly responsible for the effect on serum cholesterol levels and that kahweol is mainly responsible for the effect on liver enzyme levels. The objective of this study was to investigate whether coffee oil that only contains a minute amount of kahweol indeed does not cause elevation of liver enzyme levels. METHODS: The response of serum alanine aminotransferase (ALAT) and aspartate aminotransferase (ASAT) to Robusta coffee oil (62 mg/day cafestol, 1.6 mg/day kahweol) was measured in 18 healthy volunteers. RESULTS: After nine days one subject was taken off Robusta oil treatment due to an ALAT level of 3.6 times the upper limit of normal (ULN). Another two subjects stopped treatment due to other reasons. After 16 days another two subjects were taken off Robusta oil treatment. One of those subjects had levels of 5.8 ULN for ALAT and 2.0 ULN for ASAT; the other subject had an ALAT level of 12.4 ULN and an ASAT level of 4.7 ULN. It was then decided to terminate the study. The median response of subjects to Robusta oil after 16 days was 0.27 ULN (n = 15, 25(th),75(th )percentile: 0.09;0.53) for ALAT and 0.06 ULN (25(th),75(th )percentile -0.06;0.22) for ASAT. CONCLUSIONS: We conclude that the effect on liver enzyme levels of coffee oil containing hardly any kahweol is similar to that of coffee oil containing high amounts of kahweol. Therefore it is unlikely that kahweol is the component of coffee oil that is responsible for the effect. Furthermore, we conclude that otherwise unexplained elevation of liver enzyme levels observed in patients might be caused by a switch from consumption of filtered coffee to unfiltered coffee