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This is a study about teacher careers to elementary school principals. The aim of this contribution is to reconstruct the strategies guiding aspiring elementary school principals in their careers and to analyse those in order to answer the question: How do elementary school teachers manage to become principals? To obtain qualitative data elementary school teachers and new principals in Schleswig-Holstein were interviewed. An ethnographic approach consisting of observational research in qualification measures for principals enabled further insights. The analysis of the empirical data was accomplished using the documentary method and the theoretical concepts of Bourdieu and Goffman. The different forms and paradigms of inner orientation of the status passage into the position of principals are analysed and condensed into types.

The careful selection of ungulate calving sites to improve offspring survival is vital in the face of predation. In general, there is limited knowledge to which degree predator presence and prey's individual experience shape the selection of calving sites. Predator presence influences the spatiotemporal risk of encountering a predator, while individual experiences with previous predation events shape perceived mortality risks. We used a multi‐year movement dataset of a long‐lived female ungulate (moose, Alces alces, n = 79) and associated calf survival to test how predator presence (i.e., encounter risk) and females' individual experiences with previous calf mortality events affected their calving site selection and site fidelity. Using data from areas with and without Scandinavian brown bear (Ursus arctos) predation, we compared females' calving site selection using individual‐based analyses. Our findings suggest two things. First, bear presence influences calving site selection in this solitary living ungulate. Females in areas with bears were selected for higher shrub and tree cover and showed lower site fidelity than in the bear‐free area. Second, the individual experience of calf loss changes females' selection the following year. Females with lost calves had a lower site fidelity compared to females with surviving calves. Our findings suggest that increased vegetation cover may be important for reducing encounter risk in bear areas, possibly by improving calf concealment. Lower site fidelity might represent a strategy to make the placement of calving sites less predictable for predators. We suggest that bear presence shapes both habitat selection and calving site fidelity in a long‐lived animal, whereas the effect of individual experience with previous calf loss varies. We encourage further research on the relevance of female experience on the success of expressed anti‐predator strategies during calving periods. [ABSTRACT FROM AUTHOR]

Onshore wind power is increasingly expanding to meet global and national goals to increase renewable, clean, and fossilfree energy production. In many countries and regions, however, historical and current land use is extensive, and the expansion of wind power has to be well-tuned to avoid risking irreversible legacy losses of existing and traditional land uses, landscape values, and cultures. Hence, assessments of the siting premises of current and forecasted expansion of wind power are strongly needed as a basis for sustainable planning. We present a study from alpine to temperate biomes in Sweden, where an ambitious onshore wind power expansion strategy has been put in place and will result in Swedish landscapes that are typified by wind power. We explored the existing legal framework--i.e., the national interest for wind power according to the Swedish Environmental Code--concerning the spatial interaction with other national interests for nature conservation, landscape values, and other land uses, and the land cover, landowner, and formally protected areas distribution within wind power sites and in their proximity. We found that the national interest framework does not provide sufficient guidance for locating wind power to avoid spatial overlap with conflicting interests and values. Furthermore, our analysis revealed that wind power is located mainly in forest-dominated landscapes, and on lands where private forest companies are the dominant owners but where the proportion of public and non-industrial private ownership increases in the near surroundings. Finally, we found that large areas of formally protected areas are within the proximate areas influenced by wind power. As an extensive onshore wind power expansion is already going on, and an even more extensive expansion is projected, the ways forward toward a sustainable wind power expansion calls for integrated landscape planning approaches that are based on comprehensive assessments of existing interests and values. [ABSTRACT FROM AUTHOR]

Although the advent of high‐resolution GPS tracking technology has helped increase our understanding of individual and multispecies behavior in wildlife systems, detecting and recording direct interactions between free‐ranging animals remains difficult. In 2023, we deployed GPS collars equipped with proximity sensors (GPS proximity collars) on brown bears (Ursus arctos) and moose (Alces alces) as part of a multispecies interaction study in central Sweden. On 6 June, 2023, a collar on an adult female moose and a collar on an adult male bear triggered each other's UHF signal and started collecting fine‐scale GPS positioning data. The moose collar collected positions every 2 min for 89 min, and the bear collar collected positions every 1 min for 41 min. On 8 June, field personnel visited the site and found a female neonate moose carcass with clear indications of bear bite marks on the head and neck. During the predation event, the bear remained at the carcass while the moose moved back and forth, moving toward the carcass site about five times. The moose was observed via drone with two calves on 24 May and with only one remaining calf on 9 June. This case study describes, to the best of our knowledge, the first instance of a predation event between two free ranging, wild species recorded by GPS proximity collars. Both collars successfully triggered and switched to finer‐scaled GPS fix rates when the individuals were in close proximity, producing detailed movement data for both predator and prey during and after a predation event. We suggest that, combined with standard field methodology, GPS proximity collars placed on free‐ranging animals offer the ability for researchers to observe direct interactions between multiple individuals and species in the wild without the need for direct visual observation. [ABSTRACT FROM AUTHOR]

Differences in botanical diet compositions among a large number of moose faecal samples collected during winter correlated with the nutritional differences identified in the same samples (Mantel‐r = 0.89, p = 0.001), but the nutritional differences were significantly smaller (p < 0.001).Nutritional geometry revealed that moose mixed Scots pine Pinus sylvestris and Vaccinium spp. as nutritionally complementary foods to reach a nutritional target resembling Salix spp. twigs, and selected for Salix spp. browse (Jacob's D > 0).Available protein (AP) and total non‐structural carbohydrates (TNC) were significantly correlated in observed diets but not in hypothetical diets based on food availability.The level of Acetoacetate in moose serum (i.e. 'starvation') was weakly negatively associated with digestibility of diets (p = 0.08) and unrelated to increasing AP:TNC and AP:NDF ratios in diets (p > 0.1).Our study is the first to demonstrate complementary feeding in free‐ranging moose to attain a nutritional target that has previously been suggested in a feeding trial with captive moose. Our results add support to the hypothesis of nutritional balancing as a driver in the nutritional strategy of moose with implications for both the management of moose and food resources. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Studies of free-ranging wildlife often involve animal capture and fitting of tracking devices. Capturing wildlife may result in behavioral alterations. Thus, there is a need to evaluate the effects of capture on study animals to identify potential biases influencing the research. We assessed the short-term response of 15 GPS/GSM-collared adult female moose (Alces alces (L., 1758)) and immobilization and handling by comparing moose rates of movement and net square displacement before and after recapture. Moose were more active up to 7 h and increased their spatial displacement for 4.5 days after recapture compared with movement patterns before recapture. Opposite to our predictions, moose did not reduced their movement rates after their initial displacement following capture and recovery, i.e., moose did not show any indication for a residual effect. We recommend using individuals as their own controls in analyses of capture impacts to account adequately for individual behavioral differences. We recommend omitting data of at least the first 5 days following capture for analyses of moose movement and distribution. Les etudes sur la faune sauvage en liberie impliquent souvent la capture des animaux et la pose de dispositifs de surveillance. Cette capture de la faune sauvage peut causer des modifications des comportements. Il est donc important d'evaluer les effets de la capture sur les animaux a l'etude afin d'identifier les erreurs potentielles qui pourraient influencer la recherche. Nous evaluons les reactions a court terme de 15 elans (Alces alces (L., 1758)) femelles adultes munis de colliers GPS/GSM a l'immobilisation et la manipulation en comparant les taux de deplacement des elans et leurs deplacements nets au carre avant et apres la recapture. Apres la recapture, les elans sont plus actifs pendant une periode pouvant atteindre sept heures et augmentent leurs deplacements spatiaux pendant 4,5 jours par comparaison avec leurs patrons de deplacement avant la recapture. Contrairement a nos predictions, les elans ne diminuent pas leur taux de locomotion apres leur deplacement initial apres la capture et la recuperation, c.-a-d. les elans ne montrent aucune indication d'effet residuel. Nous recommandons d'utiliser les individus comme leurs propres temoins dans l'analyse des impacts de la capture afin de tenir compte adequatement des differences comportementales individuelles. Nous suggerons d'omettre les donnees d'au moins les cinq premiers jours apres la capture des analyses de deplacement et de repartition des elans. [Traduit par la Redaction], Introduction Studying the behavior of free-ranging wildlife often involves capture, handling, and equipping individuals with a tracking device, especially in wide-ranging wildlife that use remote areas or occur in forested [...]

Hunting is a widespread but often overlooked land-use activity, providing major benefits to society. Hunting takes place in most landscapes, yet it remains unclear which types of landscapes foster or dampen hunting-related services, and how hunting relates to other land uses. A better understanding of these relationships is key for sustainable land-use planning that integrates wildlife management. This is particularly urgent for Europe, where wildlife populations are increasing. Focusing on Sweden, we explored the spatial associations among hunting, agriculture, and forestry to identify archetypical combinations of these land uses. Specifically, we combined indicators on the extent and intensity of agriculture and forestry, with data on hunting bags for 63 game species using selforganizing maps, a non-parametric clustering approach. We identified 15 typical bundles of co-occurring land uses at the municipality level across Sweden. The harvest of forest grouse, bears, and moose co-occurred with forestry in northern Sweden, whereas the harvest of small game, different deer species, and wild boar co-occurred with agriculture across southern Sweden, reflecting species' biology, environmental factors, and management. Our findings also highlight the strength of associations among hunting and other land uses. Importantly, we identified large areas in central Sweden where harvest of game was below average, possibly indicating that intensity of hunting is out of balance with that of agriculture or forestry, potentially fostering conflict between wildlife and land use. Collectively, our results suggest that (1) hunting should be considered a major land use that, in Sweden, is more widespread than agriculture and forestry; (2) land-use planning must therefore integrate wildlife management; and (3) such an integration should occur in a regionalized manner that considers social-ecological context. Our approach identifies a first spatial template within which such context-specific land-use planning, aiming at aligning wildlife and diverse land uses, can take place. [ABSTRACT FROM AUTHOR]

Rural areas supply the planet's natural resources while simultaneously harbor refuges for most of the world's remaining biodiversity and intact, resilient ecosystems. Since traditional extractive activities must increasingly co-exist with non-exploitative activities such as tourism and conservation, sustainable land use planning is essential for managing trade-offs between incompatible interests in rural areas. With "communicative planning" being promoted since decades, participation is considered crucial for reconciling different planning interests. However, the implementation of participation remains patchy and uneven, not least in sparsely populated regions with low capacity where participation could be a game-changer. Here, we consider municipal comprehensive planning as an existing arena to explore participatory planning approaches potentially capable of simultaneously managing competing land uses and promoting sustainable development in sparsely populated rural contexts. Collaborative work between researchers and public managers resulted in the co-development of an approach based on qualitative village- and interest-based focus groups that facilitated the formulation, negotiation, and legitimization of concrete and detailed local guidelines that prioritize between different land uses. Consequently, the resulting comprehensive plan draft was more readily adopted than the output of a traditional planning process. We found that citizens in sparsely populated municipalities seem willing to actively contribute to rural development processes if they have significant influence. • Land use conflicts in sparsely populated areas depend on regulations out of reach for local people. • Researchers and public officers co-developed a participatory municipal plan process. • Concrete, detailed land use guidelines were formulated, negotiated and legitimized. • The resulting plan proposal was more readily adopted than in a traditional process. • Citizens actively contribute to rural development when they have significant influence. [ABSTRACT FROM AUTHOR]

Partial migration, whereby a proportion of a population migrates between distinct seasonal ranges, is common throughout the animal kingdom. However, studies linking existing theoretical models of migration probability, with empirical data are lacking. The competitive release hypothesis for partial migration predicts that due to density‐dependent habitat selection, the proportion of migrants increases as the relative quality and size of the seasonal range increases, but decreases with increasing migration cost and population density. To test this prediction, we developed a quantitative framework to predict the proportion of migrants, using empirical data from 545 individually GPS‐marked moose Alces alces from across Fennoscandia, spanning latitudes of 56° to 68°N. Moose contracted their ranges to common and spatially limited winter areas (typically at lower elevation), but expanded them during summer due to an increase in suitable habitat (at highland ranges). As predicted from our model, a better and larger highland range relative to the lowland range corresponded to a higher proportion of migrants in an area. Quantitative predictions coupling the balance of habitat availability of seasonal ranges with the probability of migrating in a large herbivore is a necessary step towards an enhanced understanding of the mechanisms underlying migration at the population level. [ABSTRACT FROM AUTHOR]

Optimal management of hunted species requires an understanding of the impacts of hunting on both individual animal and population levels. Recent technological advancements in biologging enable us to obtain increasingly detailed information from free-ranging animals, covering longer periods of time, and providing the data needed to assess such impacts. In Sweden, more than 80 000 moose are harvested annually, mostly hunted with the use of baying dogs. The effects of this hunting method on animal welfare and stress are understudied. Here, we evaluated 6 real and 17 experimental hunting approaches with baying dogs [wearing global positioning system (GPS) collars] on 8 adult female moose equipped with ruminal temperature loggers, subcutaneous heart rate (HR) loggers and GPS collars with accelerometers. The obtained data were used to analyse the behavioural and physiological responses of moose to hunting with dogs. Successful experimental approaches (moose and dog were within 240 m for >10 min) resulted in higher maximum body temperature (Tb, 0.88°C higher) and a mean increase in HR of 24 bpm in moose at the day of the approach compared to the day after. The moose rested on average >90 min longer the day after the approach compared to the day of the approach. The moose travelled on average 4.2 km longer and had a 1.3 m/s higher maximum speed the day of the approach compared to the day after. Our results demonstrate that hunting with dogs increase moose energy expenditure and resting time (and consequently decrease time available for foraging) on an individual level. This could possibly affect body condition and reproduction rates if the hunting disturbances occur frequently. [ABSTRACT FROM AUTHOR]

Purpose: Three‐dimensional (3D) printing allows for the fabrication of medical devices with complex geometries, such as soft actuators and robots that can be used in image‐guided interventions. This study investigates flexible and rigid 3D‐printing materials in terms of their impact on multimodal medical imaging. Methods: The generation of artifacts in clinical computer tomography (CT) and magnetic resonance (MR) imaging was evaluated for six flexible and three rigid materials, each with a cubical and a cylindrical geometry, and for one exemplary flexible fluidic actuator. Additionally, CT Hounsfield units (HU) were quantified for various parameter sets iterating peak voltage, x‐ray tube current, slice thickness, and convolution kernel. Results: We found the image artifacts caused by the materials to be negligible in both CT and MR images. The HU values mainly depended on the elemental composition of the materials and applied peak voltage was ranging between 80 and 140 kVp. Flexible, nonsilicone‐based materials were ranged between 51 and 114 HU. The voltage dependency was less than 29 HU. Flexible, silicone‐based materials were ranged between 60 and 365 HU. The voltage‐dependent influence was as large as 172 HU. Rigid materials ranged between −69 and 132 HU. The voltage‐dependent influence was <33 HU. Conclusions: All tested materials may be employed for devices placed in the field of view during CT and MR imaging as no significant artifacts were measured. Moreover, the material selection in CT could be based on the desired visibility of the material depending on the application. Given the wide availability of the tested materials, we expect our results to have a positive impact on the development of devices and robots for image‐guided interventions. [ABSTRACT FROM AUTHOR]

This work demonstrates a new method for the generation of mechanical shear wave during magnetic resonance elastography (MRE) that creates greater forces at higher vibrational frequencies as opposed to conventionally used pneumatic transducers. We developed an MR-compatible pneumatic turbine with an eccentric mass that creates a sinusoidal centrifugal force. The turbine was assessed with respect to its technical parameters and evaluated for MRE on a custom-made anthropomorphic prostate phantom. The silicone-based tissue-mimicking materials of the phantom were selected with regard to their complex shear moduli examined by rheometric testing. The tissue-mimicking materials closely matched human soft tissue elasticity values with a complex shear modulus ranging from 3.21 kPa to 7.29 kPa. We acquired MRE images on this phantom at 3 T with actuation frequencies of 50, 60 Hz, 70 Hz, and 80 Hz. The turbine generated vibrational wave amplitudes sufficiently large to entirely penetrate the phantoms during the feasibility study. Increased wave length in the stiffer inclusions compared to softer background material were detected. Our initial results suggest that silicone-based phantoms are useful for the evaluation of elasticities during MRE. Furthermore, our turbine seems suitable for the mechanical assessment of soft tissue during MRE. [ABSTRACT FROM AUTHOR]

• Semi-domestic reindeer avoid stands of the exotic tree species Pinus contorta. • Terricolous lichens as winter forage are less abundant in stands of P. contorta. • P. contorta is planted mainly on soils where terricolous lichens could thrive. • These effects reduce grazing grounds in addition to other cumulative impacts. The introduction of exotic tree species can have profound effects on the native environment, including habitat use and movement patterns of animals, as well as becoming a management challenge for other land users. Here, we used GPS data from reindeer (Rangifer tarandus) and remote sensing measurements of lichen cover and soil moisture to assess the effects of the exotic lodgepole pine (Pinus contorta) on reindeer husbandry by the Indigenous Sámi in northern Sweden. We used locational data from 67 reindeer for three winters to analyze their habitat selection at the second-order selection (placement of home range in the landscape) and third-order selection (selection of sites within the home range) in relation to land cover class, terricolous lichen cover as measure of winter forage abundance, topographic features, and distance to roads. We also analyzed remotely sensed abundance of lichens in different forest types, and the association between these forest types and soil moisture as measure of suitability as lichen habitat. Compared to native P. sylvestris , we found that reindeer avoided stands with P. contorta where trees were higher than three meters. If P. contorta was the dominant tree species, reindeer were 60 % less likely to select these stands compared to stands with P. sylvestris , and 40 % less likely if P. contorta was less dominant at both orders of selection. We also found that reindeer selected areas with higher lichen cover. Lichen cover was lower in P. contorta stands compared to stands of the native P. sylvestris , even though P. contorta occurred mainly on dry soils usually favorable for terricolous lichens. We conclude that planting P. contorta on soils suitable for terricolous lichens is likely to reduce forage availability for reindeer and turn habitats earlier preferred by reindeer into avoided habitat, resulting in an overall reduction of winter grazing grounds. The effects of stands with P. contorta , albeit covering a comparatively small percentage of the reindeer husbandry area, need to be seen in context with generally declining terricolous lichen abundance due to land uses like forestry and other cumulative effects by external pressures on reindeer husbandry. [ABSTRACT FROM AUTHOR]

Postmortem body temperature is used to estimate time of death in humans, but the available models are not validated for most nonhuman species. Here, we report that cooling in an adult female moose (Alces alces) equipped with a rumen temperature monitor was extremely slow, with a rumen temperature of 27–28 C as late as 40 h postmortem. [ABSTRACT FROM AUTHOR]

Understanding a species' feeding ecology is essential for successful management and conservation, because food abundance can influence body mass, survival, reproductive success, movements, and habitat use. We describe annual and seasonal variations in the diet of brown bears Ursus arctos in southcentral Sweden, based on analysis of 527 fecal samples from 1994-1996 and 2000-2001. There was distinct seasonal variation in most of the 26 food items we documented. Ungulates, predominantly moose Alces alces, and insects comprised most of the estimated dietary energy content in spring and summer. Insects were represented almost entirely by ants, of which Formica spp. and Camponotus herculeanus were the most common. During autumn, berries dominated the diet. The most important berry species were bilberry Vaccinium myrtillus, crowberry Empetrum hermaphoditum and lingonberry V. vitis-idaea. We determined berry availability by inventorying 308 random plots three times for two consecutive years. These three berries occurred with great spatial, seasonal and annual variation in abundance. The bears showed the strongest positive preference for bilberries, a lesser positive preference for crowberries, but no preference for lingonberries. The proportion of berries in the autmn diet was stable between years, but the relative importance of the species changed, indicating that bears switched to crowberries when bilberries were less abundant. The effects of predicted future climatic change might have severe effects on the availability of the berries, which is the only important food available for fat acquisition prior to hibernation. [ABSTRACT FROM AUTHOR]

Background Unlike metastatic colorectal cancer (CRC) there are to date few reports concerning the predictive value of molecular biomarkers on the clinical outcome in stage II/III CRC patients receiving adjuvant chemotherapy. Aim of this study was to assess the predictive value of proteins related with the EGFR-and VEGFR-signalling cascades in these patients. Methods The patients' data examined in this study were from the collective of the 5-FU/FA versus 5-FU/FA/irinotecan phase III FOGT-4 trial. Tumor tissues were stained by immunohistochemistry for VEGF-C, VEGF-D, VEGFR-3, Hif-1 α, PTEN, AREG and EREG expression and evaluated by two independent, blinded investigators. Survival analyses were calculated for all patients receiving adjuvant chemotherapy in relation to expression of all makers above. Results Patients with negative AREG and EREG expression on their tumor had a significant longer DFS in comparison to AREG/EREG positive ones(p< 0.05). The benefit on DFS in AREG- /EREG- patients was even stronger in the group that received 5-FU/FA/irinotecan as adjuvant treatment(p=0.002). Patients with strong expression of PTEN profited more in terms of OS under adjuvant treatment containing irinotecan(p< 0.05). Regarding markers of the VEGFR-pathway we found no correlation of VEGF-C- and VEGFR-3 expression with clinical outcome. Patients with negative VEGF-D expression had a trend to live longer when treated with 5-FU/FA(p=0.106). Patients who were negative for Hif-1 α, were disease-free in more than 50% at the end of the study and showed significant longer DFS-rates than those positive for Hif-1 α (p=0.007). This benefit was even stronger at the group treated with 5-FU/FA/irinotecan(p=0.026). Finally, AREG-/EREG-/PTEN+ patients showed a trend to live longer under combined treatment combination. Conclusions The addition of irinotecan to adjuvant treatment with 5-FU/FA does not provide OS or DFS benefit in patients with stage II/III CRC. Nevertheless, AREG/EREG negative, PTEN positive and Hif-1 α negative patients might profit significantly in terms of DFS from a treatment containing fluoropyrimidines and irinotecan. Our results suggest a predictive value of these biomarkers concerning adjuvant chemotherapy with 5-FU/FA +/- irinotecan in stage II/III colorectal cancer. [ABSTRACT FROM AUTHOR]

Continual expansion of human development and recreational activity into previously undisturbed environments and wildlife habitat highlights the need for better understanding of behav- ioral impacts of human-induced disturbances on wildlife, especially where harvest is the main source of mortality. In a controlled field experiment in northern Sweden, we exposed 29 adult free-ranging GPS-collared female moose (Alces alces) to either off-trail hiking or snowmobiling activity to study individual response to non-lethal human activities. Both experimental disturbances resulted in signifi- cant increase in movement rates and diurnal activity ranges, and prompted moose to leave the area. Movement rates were elevated for 1 and 2 h following hiking and snowmobiling, respectively. We found that the overall moose response to human-induced disturbances was short in duration, suggesting negligible effect on the overall energy budget of moose in good condition when disturbances occur at moderate frequency. [ABSTRACT FROM AUTHOR]

Helicopters are used for numerous wildlife management and research purposes, but can alter wildlife behaviour and influence baseline data collection. We investigated reactions of GPS-collared moose Alces alces and brown bears Ursus arctos to short-term helicopter approaches by researchers. Moose responded with up to 10 times greater movement rates for up to two hours following a helicopter approach and moved into more rugged terrain. Brown bears decreased their speed and remained within similar habitat types and terrain. The movements were influenced only about two hours and did not influence the size of the activity areas. Contrary to our predictions, brown bears responded with a somewhat calmer response than moose, illustrating response differences in large herbivores and carnivores. This difference in response might be because brown bears are actually less disturbed than moose by direct helicopter approaches or because of a difference in tactical behaviour between brown bears and moose following disturbance. Researchers and managers should thus be cautious in using knowledge from one species to predict or perceive disturbance response in another species or taxa. [ABSTRACT FROM AUTHOR]

Strong land-use pressure challenges sustainable development and calls for landscape approaches that balance economic, ecological, and socio-cultural aspects and interests. In the boreal, sub-alpine, and alpine regions in Sweden, encompassing 32 million ha, many and different land-use interests overlap, which causes risks for conflict, but potentially also suggests integration and synergy opportunities. Based on geographic information system (GIS) analyses of geographically delineated national interests regulated in the Swedish Environmental Code, including, amongst others, Natura 2000, contiguous mountains, recreation, reindeer husbandry, and wind power, and based on forestry as a dominating land use, we found extensive overlap among similar but also between dissimilar types of interest. In some mountain municipalities, our results show that the designated national interest area is four times as large as the available terrestrial area. Moreover, the overlap is much higher in the alpine than in the boreal biome, and there is increasing designation for nature conservation and a decreasing designation for national interests for culture, recreation, and tourism from south to north. We interpret the results with reference to multiple-use needs and opportunities for landscape approaches to sustainable planning. Departing from biodiversity conservation values, we also discuss opportunities to focus planning strategies on assessing synergy, integration, and conflict based on nature-based and place-based land-use characteristics. [ABSTRACT FROM AUTHOR]

Introduction: Magnetic resonance elastography (MRE) is an MR imaging method for the quantification of spatial stiffness of soft tissues using mechanically induced dynamic shear waves. In some applications, the penetration of shear waves can be limited through attenuation and shadowing of the waves. In order to increase the actuator performance, we present a dual driver approach to compensate for shear wave attenuation and to achieve better coverage over the entire region of interest. Materials and Methods: (a) We designed pneumatic turbines that created a sinusoidal centrifugal force due to an eccentric weight. Two turbines were connected in‐phase with each eccentric weight having the same angular position relative to its pivot point. (b) We developed a tissue elasticity mimicking abdominal phantom. (c) The phantom served as a test object to investigate the feasibility to generate shear waves at two surface origins with the dual actuator system and to compare it against a single actuation setup. Results and Discussion: A stable phase relationship of the shear waves generated by the turbines was achieved as the positions of the eccentric weights were mechanically fixed. The abdominal phantom yielded sufficient MR signal. Liver and rib cage were clearly visible in MR imaging. The shear waves generated by the dual turbine propagated through the region of interest. Our turbine design is reproducible through 3D printing and can be integrated into existing clinical equipment for 1.5 T and 3 T scanners. [ABSTRACT FROM AUTHOR]

In northern environments, the period of access to high-quality forage is limited, exerting strong selective pressure to optimize the timing of parturition. We analysed timing and variation in moose ( Alces alces ) parturition dates of 555 females at 18 study sites across 12° of latitude (56-68° N, 1350 km) in Sweden. We found evidence for a spatial match of parturition timing to vegetation onset, but no evidence that moose adjust parturition to vegetation onset in a given year. We found a breakpoint at 64° N. Despite adaptation across latitudes, temporal divergences occurred. Females below 64° N calved after vegetation onset and females above 64° N calved before. Here, parturition before vegetation onset might be a strategy to optimize forage utilization time with the very short growing season. Highly seasonal environments such as at higher latitudes may make it advantageous to adapt parturition towards long-term climatic patterns by matching the most favourable period. Given the direction of temporal divergence, our study suggests that climate change may have less of an impact on moose parturition at northern latitudes than southern latitudes.

In this work, the two compartment exchange model and two compartment uptake model were applied to obtain quantitative perfusion parameters in rectum carcinoma and the results were compared to those obtained by the deconvolution algorithm. Eighteen patients with newly diagnosed rectal carcinoma underwent 3 T MRI of the pelvis including a T 1 weighted dynamic contrastenhanced (DCE) protocol before treatment. Mean values for Plasma Flow (PF), Plasma Volume (PV) and Mean Transit Time (MTT) were obtained for all three approaches and visualized in parameter cards. For the two compartment models, Akaike Information Criterion (AIC) and [Formula: see text] were calculated. Perfusion parameters determined with the compartment models show results in accordance with previous studies focusing on rectal cancer DCE-CT (PF 2CX  = 68 ± 44 ml/100 ml/min, PF 2CU  = 55 ± 36 ml/100 ml/min) with similar fit quality (AIC:169 ± 81/179 ± 77, [Formula: see text]:10 ± 12/9 ± 10). Values for PF are overestimated whereas PV and MTT are underestimated compared to results of the deconvolution algorithm. Significant differences were found among all models for perfusion parameters as well as between the AIC and [Formula: see text] values. Quantitative perfusion parameters are dependent on the chosen tracer kinetic model. According to the obtained parameters, all approaches seem capable of providing quantitative perfusion values in DCE-MRI of rectal cancer.

Magnetic resonance elastography (MRE) is a technique for the quantification of tissue stiffness during MR examinations. It requires consistent methods for mechanical shear wave induction to the region of interest in the human body to reliably quantify elastic properties of soft tissues. This work proposes a novel 3D-printed mechanical actuator using the principle of centrifugal force for wave induction. The driver consists of a 3D-printed turbine vibrator powered by compressed air (located inside the scanner room) and an active driver controlling the pressure of inflowing air (placed outside the scanner room). The generated force of the proposed actuator increases for higher actuation frequencies as opposed to conventionally used air cushions. There, the displacement amplitude decreases with increasing actuation frequency resulting in a smaller signal-to-noise ratio. An initial phantom study is presented which demonstrates the feasibility of the actuator for MRE. The wave-actuation frequency was regulated in a range between 15 Hz and 60 Hz for force measurements and proved sufficiently stable (± 0.3 Hz) for any given nominal frequency. The generated forces depend on the weight of the eccentric unbalance within the turbine and ranged between 0.67 N to 2.70 N (for 15 Hz) and 3.09 N to 7.77 N (for 60 Hz). Therefore, the generated force of the presented actuator increases with rotational speed of the turbine and offers an elegant solution for sufficiently large wave actuation at higher frequencies. In future work, we will investigate an optimal ratio of the weight of unbalance to the size of turbine for appropriately large but tolerable wave actuation for a given nominal frequency.