@article{8499, abstract = {We consider the cubic defocusing nonlinear Schrödinger equation in the two dimensional torus. Fix s>1. Recently Colliander, Keel, Staffilani, Tao and Takaoka proved the existence of solutions with s-Sobolev norm growing in time. We establish the existence of solutions with polynomial time estimates. More exactly, there is c>0 such that for any K≫1 we find a solution u and a time T such that ∥u(T)∥Hs≥K∥u(0)∥Hs. Moreover, the time T satisfies the polynomial bound 0−1. However, there are major spatial differences both between glaciers and within any single glacier, exhibiting a very distinct nonlinear mass-balance profile with elevation. Through analysis of surface velocities derived from Landsat ETM+ imagery, we show that thinning occurs in areas of low velocity and low slope. These areas are prone to a general, dynamic decay of surface features and to the development of supraglacial lakes and ice cliffs, which may be responsible for a considerable increase in overall glacier ablation.}, author = {Pellicciotti, Francesca and Stephan, Christa and Miles, Evan and Herreid, Sam and Immerzeel, Walter W. and Bolch, Tobias}, issn = {1727-5652}, journal = {Journal of Glaciology}, keywords = {Earth-Surface Processes}, number = {226}, pages = {373--386}, publisher = {International Glaciological Society}, title = {{Mass-balance changes of the debris-covered glaciers in the Langtang Himal, Nepal, from 1974 to 1999}}, doi = {10.3189/2015jog13j237}, volume = {61}, year = {2015}, } @article{12631, abstract = {Air temperature is one of the most relevant input variables for snow and ice melt calculations. However, local meteorological conditions, complex topography, and logistical concerns in glacierized regions make the measuring and modeling of air temperature a difficult task. In this study, we investigate the spatial distribution of 2 m air temperature over mountain glaciers and propose a modification to an existing model to improve its representation. Spatially distributed meteorological data from Haut Glacier d'Arolla (Switzerland), Place (Canada), and Juncal Norte (Chile) Glaciers are used to examine approximate flow line temperatures during their respective ablation seasons. During warm conditions (off-glacier temperatures well above 0°C), observed air temperatures in the upper reaches of Place Glacier and Haut Glacier d'Arolla decrease down glacier along the approximate flow line. At Juncal Norte and Haut Glacier d'Arolla, an increase in air temperature is observed over the glacier tongue. While the temperature behavior over the upper part can be explained by the cooling effect of the glacier surface, the temperature increase over the glacier tongue may be caused by several processes induced by the surrounding warm atmosphere. In order to capture the latter effect, we add an additional term to the Greuell and Böhm (GB) thermodynamic glacier wind model. For high off-glacier temperatures, the modified GB model reduces root-mean-square error up to 32% and provides a new approach for distributing air temperature over mountain glaciers as a function of off-glacier temperatures and approximate glacier flow lines.}, author = {Ayala, A. and Pellicciotti, Francesca and Shea, J. M.}, issn = {2169-8996}, journal = {Journal of Geophysical Research: Atmospheres}, keywords = {Space and Planetary Science, Earth and Planetary Sciences (miscellaneous), Atmospheric Science, Geophysics}, number = {8}, pages = {3139--3157}, publisher = {American Geophysical Union}, title = {{Modeling 2 m air temperatures over mountain glaciers: Exploring the influence of katabatic cooling and external warming}}, doi = {10.1002/2015jd023137}, volume = {120}, year = {2015}, } @article{12629, abstract = {Meteorological studies in high-mountain environments form the basis of our understanding of catchment hydrology and glacier accumulation and melt processes, yet high-altitude (>4000 m above sea level, asl) observatories are rare. This research presents meteorological data recorded between December 2012 and November 2013 at seven stations in Nepal, ranging in elevation from 3860 to 5360 m asl. Seasonal and diurnal cycles in air temperature, vapour pressure, incoming short-wave and long-wave radiation, atmospheric transmissivity, wind speed, and precipitation are compared between sites. Solar radiation strongly affects diurnal temperature and vapour pressure cycles, but local topography and valley-scale circulations alter wind speed and precipitation cycles. The observed diurnal variability in vertical temperature gradients in all seasons highlights the importance of in situ measurements for melt modelling. The monsoon signal (progressive onset and sharp end) is visible in all data-sets, and the passage of the remnants of Typhoon Phailin in mid-October 2013 provides an interesting case study on the possible effects of such storms on glaciers in the region.}, author = {Shea, J.M. and Wagnon, P. and Immerzeel, W.W. and Biron, R. and Brun, F. and Pellicciotti, Francesca}, issn = {1360-0648}, journal = {International Journal of Water Resources Development}, keywords = {Water Science and Technology, Development}, number = {2}, pages = {174--200}, publisher = {Taylor & Francis}, title = {{A comparative high-altitude meteorological analysis from three catchments in the Nepalese Himalaya}}, doi = {10.1080/07900627.2015.1020417}, volume = {31}, year = {2015}, } @article{12626, abstract = {Ice cliffs have been identified as a reason for higher ablation rates on debris-covered glaciers than are implied by the insulation effects of the debris. This study aims to improve our understanding of cliff backwasting, and the role of radiative fluxes in particular. An energy-balance model is forced with new data gathered in May and October 2013 on Lirung Glacier, Nepalese Himalaya. Observations show substantial variability in melt between cliffs, between locations on any cliff and between seasons. Using a high-resolution digital elevation model we calculate longwave fluxes incident to the cliff from surrounding terrain and include the effect of local shading on shortwave radiation. This is an advance over previous studies, that made simplified assumptions on cliff geometry and radiative fluxes. Measured melt rates varied between 3.25 and 8.6 cm d−1 in May and 0.18 and 1.34 cm d−1 in October. Model results reproduce the strong variability in space and time, suggesting considerable differences in radiative fluxes over one cliff. In October the model fails to reproduce stake readings, probably due to the lack of a refreezing component. Disregarding local topography can lead to overestimation of melt at the point scale by up to ∼9%.}, author = {Steiner, Jakob F. and Pellicciotti, Francesca and Buri, Pascal and Miles, Evan S. and Immerzeel, Walter W. and Reid, Tim D.}, issn = {1727-5652}, journal = {Journal of Glaciology}, number = {229}, pages = {889--907}, publisher = {International Glaciological Society}, title = {{Modelling ice-cliff backwasting on a debris-covered glacier in the Nepalese Himalaya}}, doi = {10.3189/2015jog14j194}, volume = {61}, year = {2015}, } @article{12627, abstract = {Spatial evolution of supraglacial debris cover on mountain glaciers is a largely unmonitored and poorly understood phenomenon that directly affects glacier melt. Supraglacial debris cover for 93 glaciers in the Karakoram, northern Pakistan, was mapped from Landsat imagery acquired in 1977, 1998, 2009 and 2014. Surge-type glaciers occupy 41% of the study area and were considered separately. The time series of debris-covered surface area change shows a mean value of zero or near-zero change for both surging and non-surging glaciers. An increase in debris-covered area is often associated with negative regional mass balances. We extend this logic to suggest that the stable regional mass balances in the Karakoram explain the zero or near-zero change in debris-covered area. This coupling of trends combined with our 37 year time series of data suggests the Karakoram anomaly extends further back in time than previously known.}, author = {Herreid, Sam and Pellicciotti, Francesca and Ayala, Alvaro and Chesnokova, Anna and Kienholz, Christian and Shea, Joseph and Shrestha, Arun}, issn = {1727-5652}, journal = {Journal of Glaciology}, number = {227}, pages = {524--536}, publisher = {International Glaciological Society}, title = {{Satellite observations show no net change in the percentage of supraglacial debris-covered area in northern Pakistan from 1977 to 2014}}, doi = {10.3189/2015jog14j227}, volume = {61}, year = {2015}, } @article{1618, abstract = {CCL19 and CCL21 are chemokines involved in the trafficking of immune cells, particularly within the lymphatic system, through activation of CCR7. Concurrent expression of PSGL-1 and CCR7 in naive T-cells enhances recruitment of these cells to secondary lymphoid organs by CCL19 and CCL21. Here the solution structure of CCL19 is reported. It contains a canonical chemokine domain. Chemical shift mapping shows the N-termini of PSGL-1 and CCR7 have overlapping binding sites for CCL19 and binding is competitive. Implications for the mechanism of PSGL-1's enhancement of resting T-cell recruitment are discussed.}, author = {Veldkamp, Christopher and Kiermaier, Eva and Gabel Eissens, Skylar and Gillitzer, Miranda and Lippner, David and Disilvio, Frank and Mueller, Casey and Wantuch, Paeton and Chaffee, Gary and Famiglietti, Michael and Zgoba, Danielle and Bailey, Asha and Bah, Yaya and Engebretson, Samantha and Graupner, David and Lackner, Emily and Larosa, Vincent and Medeiros, Tysha and Olson, Michael and Phillips, Andrew and Pyles, Harley and Richard, Amanda and Schoeller, Scott and Touzeau, Boris and Williams, Larry and Sixt, Michael K and Peterson, Francis}, journal = {Biochemistry}, number = {27}, pages = {4163 -- 4166}, publisher = {American Chemical Society}, title = {{Solution structure of CCL19 and identification of overlapping CCR7 and PSGL-1 binding sites}}, doi = {10.1021/acs.biochem.5b00560}, volume = {54}, year = {2015}, } @inproceedings{12881, author = {Martius, Georg S and Olbrich, Eckehard}, booktitle = {Proceedings of the 13th European Conference on Artificial Life}, isbn = {9780262330275}, location = {York, United Kingdom}, pages = {78}, publisher = {MIT Press}, title = {{Quantifying self-organizing behavior of autonomous robots}}, doi = {10.7551/978-0-262-33027-5-ch018}, year = {2015}, } @article{12196, abstract = {SNC1 (SUPPRESSOR OF NPR1, CONSTITUTIVE 1) is one of a suite of intracellular Arabidopsis NOD-like receptor (NLR) proteins which, upon activation, result in the induction of defense responses. However, the molecular mechanisms underlying NLR activation and the subsequent provocation of immune responses are only partially characterized. To identify negative regulators of NLR-mediated immunity, a forward genetic screen was undertaken to search for enhancers of the dwarf, autoimmune gain-of-function snc1 mutant. To avoid lethality resulting from severe dwarfism, the screen was conducted using mos4 (modifier of snc1, 4) snc1 plants, which display wild-type-like morphology and resistance. M2 progeny were screened for mutant, snc1-enhancing (muse) mutants displaying a reversion to snc1-like phenotypes. The muse9 mos4 snc1 triple mutant was found to exhibit dwarf morphology, elevated expression of the pPR2-GUS defense marker reporter gene and enhanced resistance to the oomycete pathogen Hyaloperonospora arabidopsidis Noco2. Via map-based cloning and Illumina sequencing, it was determined that the muse9 mutation is in the gene encoding the SWI/SNF chromatin remodeler SYD (SPLAYED), and was thus renamed syd-10. The syd-10 single mutant has no observable alteration from wild-type-like resistance, although the syd-4 T-DNA insertion allele displays enhanced resistance to the bacterial pathogen Pseudomonas syringae pv. maculicola ES4326. Transcription of SNC1 is increased in both syd-4 and syd-10. These data suggest that SYD plays a subtle, specific role in the regulation of SNC1 expression and SNC1-mediated immunity. SYD may work with other proteins at the chromatin level to repress SNC1 transcription; such regulation is important for fine-tuning the expression of NLR-encoding genes to prevent unpropitious autoimmunity.}, author = {Johnson, Kaeli C.M. and Xia, Shitou and Feng, Xiaoqi and Li, Xin}, issn = {0032-0781}, journal = {Plant and Cell Physiology}, keywords = {Cell Biology, Plant Science, Physiology, General Medicine}, number = {8}, pages = {1616--1623}, publisher = {Oxford University Press}, title = {{The chromatin remodeler SPLAYED negatively regulates SNC1-mediated immunity}}, doi = {10.1093/pcp/pcv087}, volume = {56}, year = {2015}, } @article{13392, abstract = {The chemical behaviour of molecules can be significantly modified by confinement to volumes comparable to the dimensions of the molecules. Although such confined spaces can be found in various nanostructured materials, such as zeolites, nanoporous organic frameworks and colloidal nanocrystal assemblies, the slow diffusion of molecules in and out of these materials has greatly hampered studying the effect of confinement on their physicochemical properties. Here, we show that this diffusion limitation can be overcome by reversibly creating and destroying confined environments by means of ultraviolet and visible light irradiation. We use colloidal nanocrystals functionalized with light-responsive ligands that readily self-assemble and trap various molecules from the surrounding bulk solution. Once trapped, these molecules can undergo chemical reactions with increased rates and with stereoselectivities significantly different from those in bulk solution. Illumination with visible light disassembles these nanoflasks, releasing the product in solution and thereby establishes a catalytic cycle. These dynamic nanoflasks can be useful for studying chemical reactivities in confined environments and for synthesizing molecules that are otherwise hard to achieve in bulk solution.}, author = {Zhao, Hui and Sen, Soumyo and Udayabhaskararao, T. and Sawczyk, Michał and Kučanda, Kristina and Manna, Debasish and Kundu, Pintu K. and Lee, Ji-Woong and Král, Petr and Klajn, Rafal}, issn = {1748-3395}, journal = {Nature Nanotechnology}, keywords = {Electrical and Electronic Engineering, Condensed Matter Physics, General Materials Science, Biomedical Engineering, Atomic and Molecular Physics, and Optics, Bioengineering}, pages = {82--88}, publisher = {Springer Nature}, title = {{Reversible trapping and reaction acceleration within dynamically self-assembling nanoflasks}}, doi = {10.1038/nnano.2015.256}, volume = {11}, year = {2015}, } @article{13394, abstract = {The ability to guide the assembly of nanosized objects reversibly with external stimuli, in particular light, is of fundamental importance, and it contributes to the development of applications as diverse as nanofabrication and controlled drug delivery. However, all the systems described to date are based on nanoparticles (NPs) that are inherently photoresponsive, which makes their preparation cumbersome and can markedly hamper their performance. Here we describe a conceptually new methodology to assemble NPs reversibly using light that does not require the particles to be functionalized with light-responsive ligands. Our strategy is based on the use of a photoswitchable medium that responds to light in such a way that it modulates the interparticle interactions. NP assembly proceeds quantitatively and without apparent fatigue, both in solution and in gels. Exposing the gels to light in a spatially controlled manner allowed us to draw images that spontaneously disappeared after a specific period of time.}, author = {Kundu, Pintu K. and Samanta, Dipak and Leizrowice, Ron and Margulis, Baruch and Zhao, Hui and Börner, Martin and Udayabhaskararao, T. and Manna, Debasish and Klajn, Rafal}, issn = {1755-4349}, journal = {Nature Chemistry}, keywords = {General Chemical Engineering, General Chemistry}, pages = {646--652}, publisher = {Springer Nature}, title = {{Light-controlled self-assembly of non-photoresponsive nanoparticles}}, doi = {10.1038/nchem.2303}, volume = {7}, year = {2015}, } @article{13393, abstract = {Precise control of the self-assembly of selected components within complex mixtures is a challenging goal whose realization is important for fabricating novel nanomaterials. Herein we show that by decorating the surfaces of metallic nanoparticles with differently substituted azobenzenes, it is possible to modulate the wavelength of light at which the self-assembly of these nanoparticles is induced. Exposing a mixture of two types of nanoparticles, each functionalized with a different azobenzene, to UV or blue light induces the selective self-assembly of only one type of nanoparticles. Irradiation with the other wavelength triggers the disassembly of the aggregates, and the simultaneous self-assembly of nanoparticles of the other type. By placing both types of azobenzenes on the same nanoparticles, we created unique materials (“frustrated” nanoparticles) whose self-assembly is induced irrespective of the wavelength of the incident light.}, author = {Manna, Debasish and Udayabhaskararao, Thumu and Zhao, Hui and Klajn, Rafal}, issn = {1521-3773}, journal = {Angewandte Chemie International Edition}, keywords = {General Chemistry, Catalysis}, number = {42}, pages = {12394--12397}, publisher = {Wiley}, title = {{Orthogonal light-induced self-assembly of nanoparticles using differently substituted azobenzenes}}, doi = {10.1002/anie.201502419}, volume = {54}, year = {2015}, }