Bumblebee flower constancy and pollen diversity over time.

Bees often focus their foraging effort on a few or even a single flower species, even if other equally rewarding flower species are present. Although this phenomenon-called flower constancy-has been widely documented during single foraging trips, it is largely unknown if the behavior persists over longer time periods, especially under field conditions with large temporal variations of resources. We studied the pollen diet of individuals from nine different Bombus terrestris colonies for up to 6 weeks, to investigate flower constancy and pollen diversity of individuals and colonies, and how these change over time. We expected high degrees of flower constancy and foraging consistency over time, based on foraging theory and previous studies. Instead, we found that only 23% of the pollen foraging trips were flower constant. The fraction of constant pollen samples did not change over the study period, although repeatedly sampled individuals that were flower constant once often showed different preferences at other sampling occasions. The similarity of pollen composition in samples collected by the same individuals at different occasions dropped with time. This suggests that the flower preferences change in response to shifting floral resources. The average diversity of pollen from single foraging trips was around 2.5 pollen types, while the colony-level pollen diversity was about three times higher. How rapidly preferences change in response to shifting resources, and if this differs between and within bee species depending on factors such as size, should be the focus of future research.

Clinical, patient-reported, radiographic and magnetic resonance imaging findings 11 years after acute posterior cruciate ligament injury treated non-surgically.

BACKGROUND: Long-term consequences of posterior cruciate ligament (PCL) injury such as persistent posterior tibial translation and risk of osteoarthritis development are unclear. Additionally, little data is available describing the natural history of structural morphology of the ruptured PCL. The purpose of the study was to determine the long-term outcome after non-operatively treated PCL injury. METHODS: Over 6-years, all acute knee injuries were documented by subacute MRI (median 8 days [5-15, 25th - 75th percentile] from injury to MRI). Twenty-six patients with acute PCL injury were identified of whom 18 (69%) participated in the long-term follow-up after 11 years. Follow-up included radiographic posterior tibial translation (RPTT) determined using the Puddu axial radiograph. weight-bearing knee radiographs, MRI and KOOS (Knee injury and Osteoarthritis Outcome Score). RESULTS: On subacute MRI, 11 knees displayed total and 7 partial ruptures. At 11 (SD 1.9) years, the median RPTT was 3.7 mm (1.5-6.3, 25th - 75th percentile). Seven knees displayed radiographic osteoarthritis approximating Kellgren-Lawrence grade ≥ 2. All follow-up MRIs displayed continuity of the PCL. Patients with more severe RPTT (> 3.7 mm), had worse scores in the KOOS subscales for symptoms (mean difference 14.5, 95% CI 7-22), sport/recreation (30, 95% CI 0-65) and quality of life (25, 95% CI 13-57) than those with less severe RPTT (≤ 3.7 mm). This was also the case for the KOOS4 (22, 95% CI 9-34). CONCLUSION: Acute PCL injuries treated non-surgically display a high degree of PCL continuity on MR images 11 years after injury. However, there is a large variation of posterior tibial translation with higher values being associated with poorer patient-reported outcomes.

Incidence and concomitant chondral injuries in a consecutive cohort of primary traumatic patellar dislocations examined with sub-acute MRI.

PURPOSE: To present age- and sex-specific cumulative annual incidences of primary traumatic lateral patellar dislocation (LPD) and to detail patient characteristics and concomitant chondral injuries including osteochondral fractures, as visualized on magnetic resonance imaging (MRI), in a large consecutive cohort of knee-injured individuals. METHODS: Data on primary traumatic lateral patellar dislocations were collected from a large consecutive cohort of knee injuries examined with sub-acute MRI in a single centre with a well-defined catchment area. Annual incidences for different age-groups in relation to gender were calculated together with the risk of concomitant chondral and osteochondral injury, during sports and in general. RESULTS: A total of 184 primary patellar dislocations were identified in the cohort of 1145 acute knee injuries (n=175) and surgical records (n=9). Knee MRI was performed within a median of six days of injury. Median age of patients with primary LPD was 16 years (interquartile range, 14-21; range, 9-47) and 41% were females. Males were significantly older than females at the time of injury (median age 17 vs. 15, P = 0.021) and sustained their primary LPD during sports more often than females (65 vs. 40%, P < 0.001). Primary LPD occurred most frequently at the age of 13 to 15 years where the annual incidence was 125 (95% CI, 96-160) per 100,000 persons. The overall annual incidence of primary LPD was 14 (95% CI, 12-16) per 100,000 persons, with a predominance of males versus females (17 vs. 11, P = 0.01). Concomitant lesions to joint surfaces were displayed on MRI or during surgery in 75 (43%) knees. Osteochondral fractures were seen in 32 knees (18%). We found no statistically significant difference in the risk of osteochondral fracture between those injured during sports or during leisure activity (14 vs. 24%, P = 0.08). CONCLUSIONS: The annual incidence of first-time patellar dislocation was found to be 14 per 100,000 individuals with the highest incidence found among those aged 13-15 years. Primary LPD was more common among males and was sustained during sports activity in 55% of the cases. Associated injuries to the chondral surfaces should be expected in 43% of knees with primary LPD where 18% represent osteochondral fractures.

Clinical versus MRI grading of the medial collateral ligament in acute knee injury.

Sensitivity, specificity, and agreement between clinical and magnetic resonance imaging (MRI) gradings of the medial collateral ligament (MCL) after acute knee injury were evaluated in 362 patients. Ninety-seven per cent were injured during sports/recreation. Sensitivity and specificity of MRI for grade II or III MCL injury was 68% (95% CI 58-77%) and 90% (95% CI 86-93%), respectively. Weighted Kappa analysis showed moderate agreement between clinical and MRI grading (0.56 [95% CI 0.48-0.65]). Findings were similar for patients with and without concomitant cruciate ligament rupture (0.57 [95% CI 0.48-0.66] and 0.55 [95% CI 0.35-0.75], respectively) and for specialists in orthopaedics and knee sub-specialists (0.55 [95% CI 0.39-0.70] and 0.57 [95% CI 0.47-0.67], respectively). Agreement between clinical and MRI grading of MCL injuries by orthopaedic specialists in a general hospital is at least moderate regardless of the presence of cruciate ligament injury.

Agreement Between Clinical Examination and Magnetic Resonance Imaging in Acute Knee Trauma With Hemarthrosis.

OBJECTIVE: Hemarthrosis after knee trauma often indicates serious joint injury. Few studies have evaluated agreement between clinical examination and findings from magnetic resonance imaging (MRI). We aimed to describe the agreement between acute clinical examination and subacute MRI findings after acute knee trauma with hemarthrosis and the importance of the subspecialty of the examiner. DESIGN: Longitudinal cohort study. Agreement with MRI findings was evaluated by logistic regression. SETTING: Helsingborg hospital. PATIENTS: Thousand one hundred forty-five consecutive patients with hemarthrosis after knee trauma. INTERVENTIONS: Clinical examination and MRI. MAIN OUTCOME MEASURES: agreement between clinical examination and findings from MRI. We considered the radiologist's report as the gold standard. RESULTS: Median time (25th, 75th percentile) from injury to clinical examination was 2 (1, 7) days, and from injury to imaging was 8 (5, 15) days. The overall sensitivity and specificity of clinical examination versus MRI for major ligament injury or lateral patella dislocation (LPD) were 70% [95% confidence interval 67-73) and 66% (61-72), respectively. Orthopedic subspecialist knee had the highest agreement with anterior cruciate ligament rupture (adjusted odds ratios were 1.7 (95% confidence interval 1.2-2.3), 1.9 (1.2-3.0) and 5.9 (3.7-9.5) for orthopedic trainees, orthopedic subspecialists other, and orthopedic subspecialist knee, respectively]. For other ligament injuries and LPD, we did not find statistically significant differences. CONCLUSIONS: Clinical diagnosis after acute knee injury is relatively unreliable versus MRI findings even when performed by orthopedic specialists. However, the agreement is improved when the examination is performed by an orthopedic knee subspecialist.

Acromioclavicular joint dislocations: incidence, injury profile, and patient characteristics from a prospective case series.

BACKGROUND: Acromioclavicular joint (ACJ) dislocations are common but evidence regarding the epidemiology of these injuries is incomplete. This study aims to describe the incidence, injury mechanisms, distribution of classifications, risk factors, and patient characteristics for ACJ dislocations in a general population. METHODS: Inclusion was performed prospectively during a 4-year period with the following criteria; age 18-75 years, shoulder trauma within 2 weeks, a clinical suspicion of ACJ dislocation, and radiographs that excluded fracture. The injuries were classified according to the Rockwood system, and epidemiologic variables were obtained. Rockwood types 1-2 were defined as low-grade injuries and types 3-6 as high-grade. Age groups were defined with a young group (18-39 years), an intermediate group (40-59), and an old group (60-75). RESULTS: A total of 158 patients were included; 139 were male and the mean age was 39 years (range 18-74). There were 73 low-grade and 85 high-grade injuries. The incidence was 2.0 [95% confidence interval (CI) = 1.7-2.4] per 10,000 person-years, gradually decreasing with higher age, groupwise. The incidence rate ratio (IRR) for men vs. women was 7.6 (95% CI = 4.7-12.6) and IRR >1 was seen comparing younger age groups to older. Odds ratio calculations showed that risk factors for high-grade injury were older age and traffic accidents. CONCLUSION: The incidence of ACJ dislocations was 2.0 per 10,000 person-years in a general population. Male gender and younger age group were risk factors for injury, whereas the risk for high-grade injuries were greater in older patients and after traffic accidents.

The gracilis tendon autograft is a safe choice for orthopedic reconstructive procedures: a consecutive case series studying the effects of tendon harvesting.

BACKGROUND: The gracilis tendon is commonly used as an autograft to reconstruct torn tendons or ligaments in many parts of the body. Little is known about the subjective and functional outcome after gracilis tendon harvest. The aim of this study was to evaluate the outcome of the donor leg in patients undergoing such surgery. METHODS: Patients with chronic acromioclavicular joint dislocations undergoing coracoclavicular ligament reconstructions using autogenous gracilis tendon grafts were eligible for this study. The graft harvesting procedure was carried out in a standard fashion using a tendon stripper. Knee injury and Osteoarthritis Outcome Score (KOOS) were collected preoperatively and after 12 months. The first 5 patients were included retrospectively and lacked preoperative data, for these patients age- and gender matched normative KOOS scores were used as baseline values. Isometric knee flexor strength in 60° and 90° degrees of flexion was measured at final follow up at a median of 26 (14-56) months postoperatively with the non-operated leg used as reference. RESULTS: Twenty four patients were eligible for the study and 2 were excluded. The 22 patients available for analysis had a mean age of 44 (22-62) years at the time of surgery and 4 were women. There was no statistically significant change in KOOS 12 months postoperatively compared to baseline values but the patients were weaker in knee flexion in the operated leg compared to the non-operated one. CONCLUSIONS: Gracilis tendon harvesting results in a weakness of knee flexion but does not impair subjective knee function and is a procedure that can be recommended when an autogenous tendon graft is needed.

Competition, seed dispersal and hunting: what drives germination and seedling survival in an Afrotropical forest?

Disentangling the contributions of different processes that influence plant recruitment, such as competition and seed dispersal, is important given the increased human-mediated changes in tropical forest ecosystems. Previous studies have shown that seedling communities in an Afrotropical rainforest in southeastern Nigeria are strongly affected by the loss of important seed-dispersing primates, including Cross River gorillas (Gorilla gorilla diehli), chimpanzee (Pan troglodytes elioti) and drill (Mandrillus leucophaeus). Here we study how germination and survival of tree seedlings are affected by competition and reduced seed dispersal in three contiguous forest reserves, in southeastern Nigeria, with similar mature tree species composition and structure. We use an experimental design aimed at manipulating the effect of competition among seedlings in three protected and three hunted sites within the reserves. We use a total of sixty 5 × 5 m plots of three types: plots cleared of all seedlings, plots selectively cleared of all primate-dispersed seedlings and control plots. All seedlings were identified, measured, assigned to dispersal mode and tagged, and after 1 year we evaluated survival, mortality and new recruits. We found that in hunted sites germination of abiotically dispersed species was over four times higher in cleared plots compared to control plots, whereas germination of primate-dispersed species was the same, which indicated that dispersal limitation was the dominant force in seedling recruitment in hunted sites. This was supported by the fact that the germination of all dispersal modes in the selectively cleared plots in protected sites was similar to the control plots in the same sites, but germination of abiotically dispersed species was significantly lower than in cleared plots in hunted sites. Competition among seedlings was mostly evident from the fact that 75 % more seedlings of primate-dispersed species germinated in cleared compared to control plots in protected sites. We conclude that inter-seedling competition may be irrelevant to seedling recruitment in hunted sites, where dispersal limitation appears to be a much stronger force shaping the seedling plant community, and thus hunting indirectly reverses the importance of competition and dispersal limitation in structuring seedling communities.

Estimating effects of arable land use intensity on farmland birds using joint species modeling.

Declines in European farmland birds over past decades have been attributed to the combined effects of agricultural intensification and abandonment. Consequently, aspirations to stop declines should focus attention on reversing these changes through voluntary or policy-driven interventions. The design of such interventions should ideally be informed by scientific knowledge of which aspects of the transformation of agricultural landscapes have contributed to the farmland bird declines. Declines may be associated with loss of natural habitats or the intensification and homogenization of land use management on production land, and furthermore, these changes may interact. Here, we applied an orthogonal design exploiting spatial variation in land use in a major agricultural region of Sweden to seek evidence for benefits to farmland birds of reversing some of the intensifications on and among arable fields and whether effects are modified by the availability of seminatural habitats (pastures and field borders) in the landscape. We accounted for the potentially confounding effect of interactions between species by using a joint species distribution model explicitly controlling for additional variation and covariation among species. We found that interventions aimed specifically at land in production could provide benefits to farmland birds. Landscapes with a higher proportion leys or fallows and/or with a more diverse set of crops held higher abundances of most farmland birds. However, effects were only apparent in landscapes with low availability of seminatural habitats and were sometimes even negative in landscapes with high amounts of such habitats, demonstrating context dependence. Even if we found little evidence of interactions between species, the joint modeling approach provided several benefits. It allowed information to be shared between species making analyses robust to uncertainty due to low abundances and provided direct information about the mean and variability in effects of studied predictors among species. We also found that care needs to be taken regarding prior and distributional assumptions as the importance of species interactions might otherwise be overstated. We conclude that this approach is well suited for evaluating agricultural policies by providing evidence for or against certain interventions or to be linked to policy scenarios of land use change.

Climate warming and land-use changes drive broad-scale floristic changes in Southern Sweden.

Land-use changes, pollution and climate warming during the 20th century have caused changes in biodiversity across the world. However, in many cases, the environmental drivers are poorly understood. To identify and rank the drivers currently causing broad-scale floristic changes in N Europe, we analysed data from two vascular plant surveys of 200 randomly selected 2.5 × 2.5 km grid-squares in Scania, southernmost Sweden, conducted 1989-2006 and 2008-2015, respectively, and related the change in frequency (performance) of the species to a wide range of species-specific plant traits. We chose traits representing all plausible drivers of recent floristic changes: climatic change (northern distribution limit, flowering time), land-use change (light requirement, response to grazing/mowing, response to soil disturbance), drainage (water requirement), acidification (pH optimum), nitrogen deposition and eutrophication (N requirement, N fixation ability, carnivory, parasitism, mycorrhizal associations), pollinator decline (mode of reproduction) and changes in CO2 levels (photosynthetic pathway). Our results suggest that climate warming and changes in land-use were the main drivers of changes in the flora during the last decades. Climate warming appeared as the most influential driver, with northern distribution limit explaining 30%-60% of the variance in the GLMM models. However, the relative importance of the drivers differed among habitat types, with grassland species being affected the most by cessation of grazing/mowing and species of ruderal habitats by on-going concentration of both agriculture and human population to the most productive soils. For wetland species, only pH optimum was significantly related to species performance, possibly an effect of the increasing humification of acidic water bodies. An observed relative decline of mycorrhizal species may possibly be explained by decreasing nitrogen deposition resulting in less competition for phosphorus. We found no effect of shortage or decline of pollinating lepidopterans and bees.

Early prediction of physical activity level 1 year after stroke: a longitudinal cohort study.

OBJECTIVE: To investigate which variables present prior and early after stroke may have an impact on the level of physical activity (PA) 1 year poststroke. DESIGN: Prospective longitudinal cohort and logistic regression analysis. SETTING: Stroke Unit at Sahlgrenska University Hospital, Gothenburg, Sweden. PARTICIPANTS: 117 individuals as part of the Stroke Arm Longitudinal Study (SALGOT) admitted to the stroke unit during a period of 18 months were consecutively recruited. The inclusion criteria were: first-time stroke, impaired upper extremity function, admitted to the stroke unit within 3 days since onset, local residency and ≥18 years old. The exclusion criteria were: upper extremity condition or severe multi-impairment prior to stroke, short life expectancy and non-Swedish speaking. 77 participants followed up at 1 year poststroke were included in the analysis. PRIMARY OUTCOME: PA level 1 year after stroke was assessed using a 6-level Saltin-Grimby Scale, which was first dichotomised into mostly inactive or mostly active and second into low or moderate/high level of PA. RESULTS: Being mostly inactive 1 year after stroke could be predicted by age at stroke onset (OR 1.07, 95% CI 1.00 to 1.13, p=0.041), functional dependency at discharge (OR 7.01, 95% CI 1.73 to 28.43, p=0.006) and prestroke PA (OR 7.46, 95% CI 1.51 to 36.82, p=0.014). Having a low level of PA 1 year after stroke could be predicted by age at stroke onset (OR 1.13, 95% CI 1.06 to 1.21, p<0.001) and functional dependency at discharge (OR 3.62, 95% CI 1.09 to 12.04, p=0.036). CONCLUSIONS: Previous low level of PA, older age and functional dependency all provided value in predicting low PA 1 year after stroke. These results indicate that age and simple clinical evaluations early after stroke may be useful to help clinicians identify persons at risk of being insufficiently active after stroke. Further research is needed to clarify if these findings may apply to the large population of stroke survivors. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov (NCT01115348).

Comparison and analysis of reoperations in two different treatment protocols for trochanteric hip fractures - postoperative technical complications with dynamic hip screw, intramedullary nail and Medoff sliding plate.

BACKGROUND: In treatment of unstable trochanteric fractures dynamic hip screw and Medoff sliding plate devices are designed to allow secondary fracture impaction, whereas intramedullary nails aim to maintain fracture alignment. Different treatment protocols are used by two similar Swedish regional emergency care hospitals. Dynamic hip screw is used for fractures considered as stable within the respective treatment protocol, whereas one treatment protocol (Medoff sliding plate/dynamic hip screw) uses biaxial Medoff sliding plate for unstable pertrochanteric fractures and uniaxial Medoff sliding plate for subtrochanteric fractures, the second (intramedullary nail/dynamic hip screw) uses intramedullary nail for subtrochanteric fractures and for pertrochanteric fractures with intertrochanteric comminution or subtrochanteric extension. All orthopedic surgeries are registered in a regional database. METHODS: All consecutive trochanteric fracture operations during 2011-2012 (n = 856) and subsequent technical reoperations (n = 40) were derived from the database. Reoperations were analysed and classified into the categories adjustment (percutaneous removal of the locking screw of the Medoff sliding plate or the intramedullary nail, followed by fracture healing) or minor, intermediate (reosteosynthesis) or major (hip joint replacement, Girdlestone or persistent nonunion) technical complications. RESULTS: The relative risk of intermediate or major technical complications was 4.2 (1.2-14) times higher in unstable pertrochanteric fractures and 4.6 (1.1-19) times higher in subtrochanteric fractures with treatment protocol: intramedullary nail/dynamic hip screw, compared to treatment protocol: Medoff sliding plate/dynamic hip screw. Overall rates of intermediate and major technical complications in unstable pertrochanteric and subtrochanteric fractures were with biaxial Medoff sliding plate 0.68%, with uniaxial Medoff sliding plate 1.4%, with dynamic hip screw 3.4% and with intramedullary nail 7.2%. CONCLUSIONS: The treatment protocol based on use of biaxial Medoff sliding plate for unstable pertrochanteric and uniaxial Medoff sliding plate for subtrochanteric fractures reduced the risk of severe technical complications compared to using the treatment protocol based on dynamic hip screw and intramedullary nail.

Body Temperature Regulation in Hot Environments.

Organisms in hot environments will not be able to passively dissipate metabolically generated heat. Instead, they have to revert to evaporative cooling, a process that is energetically expensive and promotes excessive water loss. To alleviate these costs, birds in captivity let their body temperature increase, thereby entering a state of hyperthermia. Here we explore the use of hyperthermia in wild birds captured during the hot and dry season in central Nigeria. We found pronounced hyperthermia in several species with the highest body temperatures close to predicted lethal levels. Furthermore, birds let their body temperature increase in direct relation to ambient temperatures, increasing body temperature by 0.22°C for each degree of increased ambient temperature. Thus to offset the costs of thermoregulation in ambient temperatures above the upper critical temperature, birds are willing to let their body temperatures increase by up to 5°C above normal temperatures. This flexibility in body temperature may be an important mechanism for birds to adjust to predicted increasing ambient temperatures in the future.

More Efficient Virtual Shadow Maps for Many Lights.

Recently, several algorithms have been introduced that enable real-time performance for many lights in applications such as games. In this paper, we explore the use of hardware-supported virtual cube-map shadows to efficiently implement high-quality shadows from hundreds of light sources in real time and within a bounded memory footprint. In addition, we explore the utility of ray tracing for shadows from many lights and present a hybrid algorithm combining ray tracing with cube maps to exploit their respective strengths. Our solution supports real-time performance with hundreds of lights in fully dynamic high-detail scenes.

A model for habitat selection and species distribution derived from central place foraging theory.

We have developed a habitat selection model based on central place foraging theory. An individual's decision to include a patch in its habitat depends on the marginal fitness contribution of that patch, which is characterized by its quality and distance to the central place. The essence of the model we have developed is a fitness isocline which is a function of patch quality and travel time to the patch. It has two parameters: the maximum travel distance to a patch of infinite quality and a coefficient that appropriately scales quality by travel time. Patches falling below the isocline will have positive marginal fitness values and should be included in the habitat. The maximum travel distance depends on the availability and quality of patches, as well as on the forager's life history, whereas the scaling parameter mostly depends on life history properties. Using the model, we derived a landscape quality metric (which can be thought of as a connectivity measure) that sums the values of available habitat in the landscape around a central place. We then fitted the two parameters to foraging data on breeding white storks (Ciconia ciconia) and estimated landscape quality, which correlated strongly with reproductive success. Landscape quality was then calculated for a larger region where re-introduction of the species is currently going on in order to demonstrate how this model can also be regarded as a species distribution model. In conclusion, we have built a general habitat selection model for central place foragers and a novel way of estimating landscape quality based on a behaviorally scaled connectivity metric.

Phosphorus and carbon availability regulate structural composition and complexity of AM fungal mycelium.

The regulation of the structural composition and complexity of the mycelium of arbuscular mycorrhizal (AM) fungi is not well understood due to their obligate biotrophic nature. The aim of this study was to investigate the structure of extraradical mycelium at high and low availability of carbon (C) to the roots and phosphorus (P) to the fungus. We used monoxenic cultures of the AM fungus Rhizophagus irregularis (formerly Glomus intraradices) with transformed carrot roots as the host in a cultivation system including a root-free compartment into which the extraradical mycelium could grow. We found that high C availability increased hyphal length and spore production and anastomosis formation within individual mycelia. High P availability increased the formation of branched absorbing structures and reduced spore production and the overall length of runner hyphae. The complexity of the mycelium, as indicated by its fractal dimensions, increased with both high C and P availability. The results indicate that low P availability induces a growth pattern that reflects foraging for both P and C. Low C availability to AM roots could still support the explorative development of the mycelium when P availability was low. These findings help us to better understand the development of AM fungi in ecosystems with high P input and/or when plants are subjected to shading, grazing or any management practice that reduces the photosynthetic ability of the plant.

Bushmeat hunting changes regeneration of African rainforests.

To assess ecological consequences of bushmeat hunting in African lowland rainforests, we compared paired sites, with high and low hunting pressure, in three areas of southeastern Nigeria. In hunted sites, populations of important seed dispersers-both small and large primates (including the Cross River gorilla, Gorilla gorilla diehli)-were drastically reduced. Large rodents were more abundant in hunted sites, even though they are hunted. Hunted and protected sites had similar mature tree communities dominated by primate-dispersed species. In protected sites, seedling communities were similar in composition to the mature trees, but in hunted sites species with other dispersal modes dominated among seedlings. Seedlings emerging 1 year after clearing of all vegetation in experimental plots showed a similar pattern to the standing seedlings. This study thus verifies the transforming effects of bushmeat hunting on plant communities of tropical forests and is one of the first studies to do so for the African continent.

Is population structure in the European white stork determined by flyway permeability rather than translocation history?

European white stork are long considered to diverge to eastern and western migration pools as a result of independent overwintering flyways. In relatively recent times, the western and northern distribution has been subject to dramatic population declines and country-specific extirpations. A number of independent reintroduction programs were started in the mid 1950s to bring storks back to historical ranges. Founder individuals were sourced opportunistically from the Eastern and Western European distributions and Algeria, leading to significant artificial mixing between eastern and western flyways. Here we use mitochondrial and microsatellite DNA to test the contention that prior to translocation, eastern and western flyways were genetically distinct. The data show a surprising lack of structure at any spatial or temporal scale suggesting that even though birds were moved between flyways, there is evidence of natural mixing prior to the onset of translocation activities. Overall a high retention of genetic diversity, high N ef , and an apparent absence of recent genetic bottleneck associated with early 20th century declines suggest that the species is well equipped to respond to future environmental pressures.

Assessing habitat quality of farm-dwelling house sparrows in different agricultural landscapes.

Having historically been abundant throughout Europe, the house sparrow (Passer domesticus) has in recent decades suffered severe population declines in many urban and rural areas. The decline in rural environments is believed to be caused by agricultural intensification, which has resulted in landscape simplification. We used giving-up densities (GUDs) of house sparrows feeding in artificial food patches placed in farmlands of southern Sweden to determine habitat quality during the breeding season at two different spatial scales: the landscape and the patch scale. At the landscape scale, GUDs were lower on farms in homogeneous landscapes dominated by crop production compared to more heterogeneous landscapes with mixed farming or animal husbandry. At the patch level, feeding patches with a higher predation risk (caused by fitting a wall to the patch to obstruct vigilance) had higher GUDs. In addition, GUDs were positively related to population size, which strongly implies that GUDs reflect habitat quality. However, the increase followed different patterns in homogeneous and heterogeneous landscapes, indicating differing population limiting mechanisms in these two environments. We found no effect of the interaction between patch type and landscape type, suggesting that predation risk was similar in both landscape types. Thus, our study suggests that simplified landscapes constitute a poorer feeding environment for house sparrows during breeding, that the population-regulating mechanisms in the landscapes differ, but that predation risk is the same across the landscape types.

Cancer drug-resistance and a look at specific proteins: Rho GDP-dissociation inhibitor 2, Y-box binding protein 1, and HSP70/90 organizing protein in proteomics clinical application.

Resistance to anti-cancer drugs is a well recognized problem and very often it is responsible for failure of the cancer treatment. In this study, the proteome alterations associated with the development of acquired resistance to cyclin-depedent kinases inhibitor bohemine, a promising anti-cancer drug, were analyzed with the primary aim of identifying potential targets of resistance within the cell that could pave a way to selective elimination of specific resistant cell types. A model of parental susceptible CEM T-lymphoblastic leukemia cells and its resistant counterpart CEM-BOH was used and advanced 2-D liquid chromatography was applied to fractionate cellular proteins. Differentially expressed identified proteins were further verified using immunoblotting and immunohistochemistry. Our study has revealed that Rho GDP-dissociation inhibitor 2, Y-box binding protein 1, and the HSP70/90 organizing protein have a critical role to play in resistance to cyclin-depedent kinases inhibitor. The results indicated not only that quantitative protein changes play an important role in drug-resistance, but also that there are various other parameters such as truncation, post-translational modification(s), and subcellular localization of selected proteins. Furthermore, these proteins were validated for their roles in drug resistance using different cell lines resistant to diverse representatives of anti-cancer drugs such as vincristine and daunorubicin.