Blinking Phase-Change Nanocapsules Enable Background-Free Ultrasound Imaging

Microbubbles are widely used as contrast agents to improve the diagnostic capability of conventional, highly speckled, low-contrast ultrasound imaging. However, while microbubbles can be used for molecular imaging, these agents are limited to the vascular space due to their large size (\u3e 1 μm). Smaller microbubbles are desired but their ultrasound visualization is limited due to lower echogenicity or higher resonant frequencies. Here we present nanometer scale, phase changing, blinking nanocapsules (BLInCs), which can be repeatedly optically triggered to provide transient contrast and enable background-free ultrasound imaging. In response to irradiation by near-infrared laser pulses, the BLInCs undergo cycles of rapid vaporization followed by recondensation into their native liquid state at body temperature. High frame rate ultrasound imaging measures the dynamic echogenicity changes associated with these controllable, periodic phase transitions. Using a newly developed image processing algorithm, the blinking particles are distinguished from tissue, providing a background-free image of the BLInCs while the underlying B-mode ultrasound image is used as an anatomical reference of the tissue. We demonstrate the function of BLInCs and the associated imaging technique in a tissue-mimicking phantom and in vivo for the identification of the sentinel lymph node. Our studies indicate that BLInCs may become a powerful tool to identify biological targets using a conventional ultrasound imaging system

Balancing stability and flexibility in adaptive governance: an analysis of tools available in U.S. environmental law

Adaptive governance must work “on the ground,” that is, it must operate through structures and procedures that the people it governs perceive to be legitimate and fair, as well as incorporating processes and substantive goals that are effective in allowing social-ecological systems (SESs) to adapt to climate change and other impacts. To address the continuing and accelerating alterations that climate change is bringing to SESs, adaptive governance generally will require more flexibility than prior governance institutions have often allowed. However, to function as good governance, adaptive governance must pay real attention to the problem of how to balance this increased need for flexibility with continuing governance stability so that it can foster adaptation to change without being perceived or experienced as perpetually destabilizing, disruptive, and unfair. Flexibility and stability serve different purposes in governance, and a variety of tools exist to strike different balances between them while still preserving the governance institution’s legitimacy among the people governed. After reviewing those purposes and the implications of climate change for environmental governance, we examine psychological insights into the structuring of adaptive governance and the variety of legal tools available to incorporate those insights into adaptive governance regimes. Because the substantive goals of governance systems will differ among specific systems, we do not purport to comment on what the normative or substantive goals of law should be. Instead, we conclude that attention to process and procedure (including participation), as well as increased use of substantive standards (instead of rules), may allow an increased level of substantive flexibility to operate with legitimacy and fairness, providing the requisite levels of psychological, social, and economic stability needed for communities to adapt successfully to the Anthropocene

Climate-induced changes in river flow regimes will alter future bird distributions

Anthropogenic forcing of the climate is causing an intensification of the global water cycle, leading to an increase in the frequency and magnitude of floods and droughts. River flow shapes the ecology of riverine ecosystems and climate-driven changes in river flows are predicted to have severe consequences for riverine species, across all levels of trophic organization. However, understanding species' responses to variation in flow is limited through a lack of quantitative modelling of hydroecological interactions. Here, we construct a Bioclimatic Envelope Model (BEM) ensemble based on a suite of plausible future flow scenarios to show how predicted alterations in flow regimes may alter the distribution of a predatory riverine species, the White-throated Dipper (Cinclus cinclus). Models predicted a gradual diminution of dipper probability of occurrence between present day and 2098. This decline was most rapid in western areas of Great Britain and was principally driven by a projected decrease in flow magnitude and variability around low flows. Climate-induced changes in river flow may, therefore, represent a previously unidentified mechanism by which climate change may mediate range shifts in birds and other riverine biota

Balancing stability and flexibility in adaptive governance: an analysis of tools available in U.S. environmental law

Adaptive governance must work “on the ground,” that is, it must operate through structures and procedures that the people it governs perceive to be legitimate and fair, as well as incorporating processes and substantive goals that are effective in allowing social-ecological systems (SESs) to adapt to climate change and other impacts. To address the continuing and accelerating alterations that climate change is bringing to SESs, adaptive governance generally will require more flexibility than prior governance institutions have often allowed. However, to function as good governance, adaptive governance must pay real attention to the problem of how to balance this increased need for flexibility with continuing governance stability so that it can foster adaptation to change without being perceived or experienced as perpetually destabilizing, disruptive, and unfair. Flexibility and stability serve different purposes in governance, and a variety of tools exist to strike different balances between them while still preserving the governance institution’s legitimacy among the people governed. After reviewing those purposes and the implications of climate change for environmental governance, we examine psychological insights into the structuring of adaptive governance and the variety of legal tools available to incorporate those insights into adaptive governance regimes. Because the substantive goals of governance systems will differ among specific systems, we do not purport to comment on what the normative or substantive goals of law should be. Instead, we conclude that attention to process and procedure (including participation), as well as increased use of substantive standards (instead of rules), may allow an increased level of substantive flexibility to operate with legitimacy and fairness, providing the requisite levels of psychological, social, and economic stability needed for communities to adapt successfully to the Anthropocene

Proteomics of canine lymphoma identifies potential cancer-specific protein markers

Purpose: Early diagnosis of cancer is crucial for the success of treatment of the disease, and there is a need for markers whose differential expression between disease and normal tissue could be used as a diagnostic tool. Spontaneously occurring malignancies in pets provide a logical tool for translational research for human oncology. Lymphoma, one of the most common neoplasms in dogs, is similar to human non-Hodgkin's lymphoma and could serve as an experimental model system. Experimental Design: Thirteen lymph nodes from normal dogs and 11 lymph nodes from dogs with B-cell lymphoma were subjected to proteomic analysis using two-dimensional PAGE separation and matrix-assisted laser desorption/ionization time-of-flight analysis. Results: A total of 93 differentially expressed spots was subjected to matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry analysis, and several proteins that showed differential expression were identified. Of these, prolidase (proline dipeptidase), triosephosphate isomerase, and glutathione S-transferase were down-regulated in lymphoma samples, whereas macrophage capping protein was up-regulated in the lymphoma samples. Conclusions: These proteins represent potential markers for the diagnosis of lymphoma and should be further investigated in human samples for validation of their utility as diagnostic markers

Alcohol Consumption Impairs the Ependymal Cilia Motility in the Brain Ventricles

Ependymal cilia protrude into the central canal of the brain ventricles and spinal cord to circulate the cerebral spinal fluid (CSF). Ependymal cilia dysfunction can hinder the movement of CSF leading to an abnormal accumulation of CSF within the brain known as hydrocephalus. Although the etiology of hydrocephalus was studied before, the effects of ethanol ingestion on ependymal cilia function have not been investigated in vivo. Here, we report three distinct types of ependymal cilia, type-I, type-II and type-III classified based upon their beating frequency, their beating angle, and their distinct localization within the mouse brain-lateral ventricle. Our studies show for the first time that oral gavage of ethanol decreased the beating frequency of all three types of ependymal cilia in both the third and the lateral rat brain ventricles in vivo. Furthermore, we show for the first time that hydin, a hydrocephalus-inducing gene product whose mutation impairs ciliary motility, and polycystin-2, whose ablation is associated with hydrocephalus are colocalized to the ependymal cilia. Thus, our studies reinforce the presence of three types of ependymal cilia in the brain ventricles and demonstrate the involvement of ethanol as a risk factor for the impairment of ependymal cilia motility in the brain

On the origin of 140 GHz emission from the 4 July 2012 solar flare

The sub-THz event observed on the 4 July 2012 with the Bauman Moscow State Technical University Radio Telescope RT-7.5 at 93 and 140~GHz as well as Kislovodsk and Mets\"ahovi radio telescopes, Radio Solar Telescope Network (RSTN), GOES, RHESSI, and SDO orbital stations is analyzed. The spectral flux between 93 and 140 GHz has been observed increasing with frequency. On the basis of the SDO/AIA data the differential emission measure has been calculated. It is shown that the thermal coronal plasma with the temperature above 0.5~MK cannot be responsible for the observed sub-THz flare emission. The non-thermal gyrosynchrotron mechanism can be responsible for the microwave emission near $10$~GHz but the observed millimeter spectral characteristics are likely to be produced by the thermal bremsstrahlung emission from plasma with a temperature of about 0.1~MK.Comment: 18 pages, 6 figure

Avian community responses to variability in river hydrology

River flow is a major driver of morphological structure and community dynamics in riverine-floodplain ecosystems. Flow influences in-stream communities through changes in water velocity, depth, temperature, turbidity and nutrient fluxes, and perturbations in the organisation of lower trophic levels are cascaded through the food web, resulting in shifts in food availability for consumer species. River birds are sensitive to spatial and phenological mismatches with aquatic prey following flow disturbances; however, the role of flow as a determinant of riparian ecological structure remains poorly known. This knowledge is crucial to help to predict if, and how, riparian communities will be influenced by climate-induced changes in river flow characterised by more extreme high (i.e. flood) and/or low (i.e. drought) flow events. Here, we combine national-scale datasets of river bird surveys and river flow archives to understand how hydrological disturbance has affected the distribution of riparian species at higher trophic levels. Data were analysed for 71 river locations using a Generalized Additive Model framework and a model averaging procedure. Species had complex but biologically interpretable associations with hydrological indices, with species' responses consistent with their ecology, indicating that hydrological-disturbance has implications for higher trophic levels in riparian food webs. Our quantitative analysis of river flow-bird relationships demonstrates the potential vulnerability of riparian species to the impacts of changing flow variability and represents an important contribution in helping to understand how bird communities might respond to a climate change-induced increase in the intensity of floods and droughts. Moreover, the success in relating parameters of river flow variability to species' distributions highlights the need to include river flow data in climate change impact models of species' distributions

Probing the Formation of Reactive Oxygen Species by a Porous Self- Assembled Benzophenone Bis-Urea Host

Herein, we examine the photochemical formation of reactive oxygen species (ROS) by a porous benzophenone-containing bis-urea host (1) to investigate the mechanism of photooxidations that occur within the confines of its nanochannels. UV irradiation of the self-assembled host in the presence of molecular oxygen generates both singlet oxygen and superoxide when suspended in solution. The efficiency of ROS generation by the host is lower than that of benzophenone (BP), which could be beneficial for reactions carried out catalytically, as ROS species react quickly and often unselectively. Superoxide formation was detected through reaction with 5,5- dimethyl-1-pyrroline N-oxide in the presence of methanol. However, it is not detected in CHCl3, as it reacts rapidly with the solvent to generate methaneperoxy and chloride anions, similar to BP. The lifetime of airborne singlet oxygen (τΔairborne) was examined at the air−solid outer surface of the host and host·quencher complexes and suggests that quenching is a surface phenomenon. The efficiency of the host and BP as catalysts was compared for the photooxidation of 1-methyl-1-cyclohexene in solution. Both the host and BP mediate the photooxidation in CHCl3, benzene, and benzene-d6, producing primarily epoxide-derived products with low selectivity likely by both type I and type II photooxidation processes. Interestingly, in CHCl3, two chlorohydrins were also formed, reflecting the formation of chloride in this solvent. In contrast, UV irradiation of the host·guest crystals in an oxygen atmosphere produced no epoxide and appeared to favor mainly the type II processes. Photolysis afforded high conversion to only three products: an enone, a tertiary allylic alcohol, and a diol, which demonstrates the accessibility of the encapsulated reactants to oxygen and the influence of confinement on the reaction pathway

River birds’ response to hydrological extremes : new vulnerability index and conservation implications

AbstractThere is growing evidence that as a consequence of climate change the frequency of extreme hydrological events will increase. Predicting the impacts of these extreme events on ecological systems is a major research challenge. It is predicted that change in future river flows, characterised by greater occurrence of floods and droughts, will have profound impacts on aquatic invertebrate communities by removing sensitive species and restructuring food networks. However, it remains unclear how an increase in these hydrological extremes will impact on riparian communities and species at higher trophic levels. Here, we describe a new methodology that facilitates the integration of quantitative outputs of species’ distribution models with the expert knowledge of conservation practitioners to produce a species’ vulnerability index (SVI). Using our SVI framework, we assessed and ranked the vulnerability of 16 river bird species to a potential climate-induced shift in the frequency, duration and magnitude of flood and drought events. Vulnerability was associated primarily with ecological traits that restrict species to in-channel riverine habitat. Whilst the SVI was developed to assess species’ vulnerability to hydrological extremes on rivers, it is equally applicable to other environmental domains as well as a range of avian and non-avian taxa. Furthermore, this original methodological approach provides researchers and managers with a valuable conservation tool that allows them to identify the species most vulnerable to climate change impacts and plan mitigation and adaptation strategies