The global distribution of cooperatively breeding birds is highly uneven, with hotspots in Australasia and sub-Saharan Africa. The ecological drivers of this distribution remain enigmatic yet could ...yield insights into the evolution and persistence of cooperative breeding. We report that the global distributions of avian obligate brood parasites and cooperatively breeding passerines are tightly correlated and that the uneven phylogenetic distribution of cooperative breeding is associated with the uneven targeting of hosts by brood parasites. With a long-term field study, we show that brood parasites can acquire superior care for their young by targeting cooperative breeders. Conversely, host defenses against brood parasites are strengthened by helpers at the nest. Reciprocally selected interactions between brood parasites and cooperative breeders may therefore explain the close association between these two breeding systems.
Cells establish and sustain structural and functional integrity of the genome to support cellular identity and prevent malignant transformation. In this review, we present a strategic overview of ...epigenetic regulatory mechanisms including histone modifications and higher order chromatin organization (HCO) that are perturbed in breast cancer onset and progression. Implications for dysfunctions that occur in hormone regulation, cell cycle control, and mitotic bookmarking in breast cancer are considered, with an emphasis on epithelial‐to‐mesenchymal transition and cancer stem cell activities. The architectural organization of regulatory machinery is addressed within the contexts of translating cancer‐compromised genomic organization to advances in breast cancer risk assessment, diagnosis, prognosis, and identification of novel therapeutic targets with high specificity and minimal off target effects.
We present an analysis of the evolution of the smoke plume caused by the Black Saturday bushfires, which started on 7 February 2009 in the Australian state of Victoria. Within 3 days this smoke plume ...was located at altitudes between 15 and 20 km thousands of kilometers away from its source region. Standard explanations for high tropospheric and lower stratospheric absorbing aerosols are either volcanic eruptions or pyroconvection. We performed a detailed analysis of various satellite observations, forward trajectory calculations, and meteorological conditions during the fire episode, yet we could not find evidence of either of these standard mechanisms explaining the observed plume evolution. Pyroconvection observed within the initial smoke plumes remained predominantly below 10 km altitude. Furthermore, there are not active volcanoes in the region. We postulate that the subsequent rise beyond approximately 10 km altitude during the first 3 days after the fires started was caused by absorption of short‐wave solar radiation in the plume. Observations indicate that the plume was highly absorptive and optically very thick. One‐dimensional plume height radiative transfer calculations with realistic assumptions about the optical properties of the smoke show that the plume could rise to 16–18 km after 5 days and up to 20 km after 10 days. The plume rise exhibits a characteristic step‐like time evolution that tracks the variation in diurnal insolation and resembles an escalator. We argue that this is the first time that this mechanism, known as “self‐lifting,” has been observed on a large scale. The key features of this mechanism and its implications are briefly discussed.
Key Points
Absorbing aerosols can cause their own lift by absorption of solar radiation
First observational evidence that this process acts on a large scale
Radiative modeling based on aerosol optical properties supports this idea
The ultraviolet (UV) Absorbing Aerosol Index (AAI) is widely used as an indicator for the presence of absorbing aerosols in the atmosphere. Here we consider the TROPOMI AAI based on the 340 nm/380 nm ...wavelength pair. We investigate the effects of clouds on the AAI observed at small and large scales. The large-scale effects are studied using an aggregate of TROPOMI measurements over an area mostly devoid of absorbing aerosols (Pacific Ocean). The study reveals that several structural features can be distinguished in the AAI, such as the cloud bow, viewing zenith angle dependence, sunglint, and a previously unexplained increase in AAI values at extreme viewing and solar geometries. We explain these features in terms of the bidirectional reflectance distribution function (BRDF) of the scene in combination with the different ratios of diffuse and direct illumination of the surface at 340 and 380 nm. To reduce the dependency on the BRDF and homogenize the AAI distribution across the orbit, we present three different AAI retrieval models: the traditional Lambertian scene model (LSM), a Lambertian cloud model (LCM), and a scattering cloud model (SCM). We perform a model study to assess the propagation of errors in auxiliary databases used in the cloud models. The three models are then applied to the same low-aerosol region. Results show that using the LCM and SCM gives on average a higher AAI than the LSM. Additionally, a more homogeneous distribution is retrieved across the orbit. At the small scale, related to the high spatial resolution of TROPOMI, strong local increases and decreases in AAI are observed in the presence of clouds. The BRDF effect presented here is a first step – more research is needed to explain the small-scale cloud effects on the AAI.
Duchenne muscular dystrophy (DMD) is a genetic disorder caused by loss of the protein dystrophin. In humans, DMD has early onset, causes developmental delays, muscle necrosis, loss of ambulation, and ...death. Current animal models have been challenged by their inability to model the early onset and severity of the disease. It remains unresolved whether increased sarcoplasmic calcium observed in dystrophic muscles follows or leads the mechanical insults caused by the muscle’s disrupted contractile machinery. This knowledge has important implications for patients, as potential physiotherapeutic treatments may either help or exacerbate symptoms, depending on how dystrophic muscles differ from healthy ones. Recently we showed how burrowing dystrophic (dys-1) C. elegans recapitulate many salient phenotypes of DMD, including loss of mobility and muscle necrosis. Here, we report that dys-1 worms display early pathogenesis, including dysregulated sarcoplasmic calcium and increased lethality. Sarcoplasmic calcium dysregulation in dys-1 worms precedes overt structural phenotypes (e.g., mitochondrial, and contractile machinery damage) and can be mitigated by reducing calmodulin expression. To learn how dystrophic musculature responds to altered physical activity, we cultivated dys-1 animals in environments requiring high intensity or high frequency of muscle exertion during locomotion. We find that several muscular parameters (e.g., size) improve with increased activity. However, longevity in dystrophic animals was negatively associated with muscular exertion, regardless of effort duration. The high degree of phenotypic conservation between dystrophic worms and humans provides a unique opportunity to gain insight into the pathology of the disease as well as the initial assessment of potential treatment strategies.
We tested a new formulation of verbenone, an antiaggregation pheromone of the mountain pine beetle (
Dendroctonus ponderosae Hopkins) (Coleoptera: Curculionidae: Scolytinae), for area-wide protection ...of lodgepole pine (
Pinus contorta Douglas ex Loudon) stands in the western United States. Helicopter applications of verbenone-releasing laminated flakes were made at the rate of 370
g of active ingredient/ha to two sites, one in California and one in Idaho, during summer 2005. Each site consisted of five 20.23-ha treated plots and five matching 20.23-ha untreated plots. We assessed
D. ponderosae flight into study plots using traps baited with aggregation pheromones and we tallied
D. ponderosae attack rates on
P. contorta trees in treated and control plots before and after application. There were no significant differences between numbers of
D. ponderosae trapped on treated and control plots. However, a significantly smaller proportion of
P. contorta trees was attacked in treated plots than in control plots at both sites; the attack rate in untreated stands was roughly three times that of treated stands in both California and Idaho, even at this low application rate. Furthermore, attack rate in 2004 was a significant explanatory variable for the response in 2005 regardless of treatment in both California and Idaho. There was no significant treatment effect at either site on attraction of
Temnochila chlorodia (Coleoptera: Trogositidae) Mannerheim, a key predator of
D. ponderosae, to the prey aggregation pheromone.
Water reuse has the potential to substantially reduce the demand on groundwater and surface water. This study presents a method to evaluate the potential of water reuse schemes in a regional context ...and demonstrates how water reuse propagates through the water system and potentially reduces pressure on groundwater resources. The use of Sankey diagram visualisation provides a valuable tool to explore and evaluate regional application of water reuse, its potential to reduce groundwater and surface water demand, and the possible synergies and trade-offs between sectors. The approach is demonstrated for the Dutch anthropogenic water system in the current situation and for a future scenario with increased water demand and reduced water availability due to climate change. Four types of water reuse are evaluated by theoretically upscaling local or regional water reuse schemes based on local reuse examples currently in operation in the Netherlands or Flanders: municipal and industrial wastewater effluent reuse for irrigation, effluent reuse for industrial applications, and reuse for groundwater replenishment. In all cases, water reuse has the potential to significantly reduce groundwater extraction volume, and thus to alleviate the pressure on the groundwater system. The water-quantity based analysis is placed in the context of water quality demands, health and safety aspects, technological requirements, regulations, public perception, and its net impact on the environment. This integrative context is essential for a successful implementation of water reuse in practice.
To study mortality and causes of death in an unselected geographically defined cohort of patients with traumatic spinal cord injury (TSCI), 1952-2001.
Patients were identified from hospital records. ...The date of death was obtained from the National Population Register, and causes of death recorded by linkage to the Norwegian Cause of Death Registry. Patient mortality was compared with mortality in the Norwegian population using standardised mortality ratios (SMR) adjusted for age and gender.
401 patients (70 women and 331 men) were identified. By 31 August 2008, 173 were dead. Median survival time in deceased patients was 7.4 years; 6.9 years for patients with cervical injuries and 8.2 years for patients with thoracolumbosacral injuries (TLS). TSCI patients had an increased mortality (SMR 1.85) compared with the Norwegian population. SMR did not change during the observation period. SMR was significantly higher for women than for men (2.88 vs 1.72), and higher in patients with complete TSCI compared with patients with incomplete TSCI (4.23 vs 1.25). SMR was 6.70 for patients with complete cervical injuries and 3.07 for patients with complete TLS injuries. Cause specific SMR were 1.96 for respiratory disease, and for suicide including accidental poisoning 3.70 for men and 37.59 for women.
Patients with a TSCI, and especially women, have an increased mortality despite modern treatment and care. Special attention should be paid to respiratory dysfunction and pulmonary infections, and to prevent suicide and accidental poisoning.
We tested methylcyclohexenone (MCH), an anti-aggregation pheromone for the Douglas-fir beetle (
Dendroctonus pseudotsugae), for protection of Douglas-fir (
Pseudotsuga menziesii) stands by applying ...MCH-releasing polymer flakes by helicopter twice during summer 2006 to five 4.05-ha plots in the State of Washington, USA. Five similar plots served as untreated controls. We assessed
D. pseudotsugae flight into study plots using baited pheromone traps, and tallied
D. pseudotsugae attack rates on all
P. menziesii trees in 2005 and 2006. We also measured stand basal area and incorporated that as an explanatory variable in the analysis. Significantly fewer
D. pseudotsugae were trapped in treated plots than in control plots, and significantly fewer
P. menziesii trees were attacked in treated plots than in control plots. The attack rate in untreated stands was nearly 10 times that of treated plots, and stands with higher basal area were significantly more likely to be attacked by
D. pseudotsugae than were stands of lower basal area. Attack rates in 2006 and 2005 were significantly correlated, regardless of treatment.
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