Subglacial sedimentary basins focus key vulnerabilities of the Antarctic ice-sheet

Antarctica preserves Earth’s largest ice sheet which, in response to climate warming, may lose ice mass and raise sea level by several metres. The ice-sheet bed exerts critical controls on dynamic mass loss through feedbacks between water and heat fluxes, topographic forcing and basal sliding. Here we show that through hydrogeological processes, sedimentary basins amplify critical feedbacks that are known to impact ice-sheet retreat dynamics. We create a high-resolution subglacial bedrock classification for Antarctica by applying a supervised machine learning method to geophysical data, revealing the distribution of sedimentary basins. Sedimentary basins are found in the upper reaches of Antarctica’s most rapidly changing ice streams, including Thwaites and Pine Island Glaciers. Hydro-mechanical numerical modelling reveals that where sedimentary basins exist, water discharge rate scales with the rate of ice unloading and the resulting hydrological instabilities are likely to amplify further retreat and unloading. These results indicate that the presence of a sedimentary bed in the catchment focuses instabilities that increase the vulnerability of the ice streams to rapid retreat and enhanced dynamic mass loss.

Mass photometry enables label-free tracking and mass measurement of single proteins on lipid bilayers

The quantification of membrane-associated biomolecular interactions is crucial to our understanding of various cellular processes. State-of-the-art single-molecule approaches rely largely on the addition of fluorescent labels, which complicates the quantification of the involved stoichiometries and dynamics because of low temporal resolution and the inherent limitations associated with labeling efficiency, photoblinking and photobleaching. Here, we demonstrate dynamic mass photometry, a method for label-free imaging, tracking and mass measurement of individual membrane-associated proteins diffusing on supported lipid bilayers. Application of this method to the membrane remodeling GTPase, dynamin-1, reveals heterogeneous mixtures of dimer-based oligomers, oligomer-dependent mobilities, membrane affinities and (dis)association of individual complexes. These capabilities, together with assay-based advances for studying integral membrane proteins, will enable the elucidation of biomolecular mechanisms in and on lipid bilayers.

Dynamic Mass Loss from Greenland's Peripheral Glaciers

While global glacier mass balance has decreased rapidly over the last two decades, mass loss has been greatest in regions with marine-terminating glaciers. In Greenland, peripheral glaciers and ice caps (GICs) cover only ~5% of Greenland’s area but contributed ~14-20% of the island’s ice mass loss between 2003-2008. Although Greenland GIC’s mass loss due to surface meltwater runoff have been estimated using atmospheric models, mass loss due to changes in ice discharge into surrounding ocean basins (i.e., dynamic mass loss) remains unquantified. Here, we use the flux gate method to estimate discharge from Greenland’s 594 marine-terminating peripheral glaciers between 1985 – 2018, and compute dynamic mass loss as the discharge anomaly relative to the 1985-1998 period. Greenland GIC discharge averages 2.14 Gt/yr from 1985-1998 and abruptly increases to an average of 3.87 Gt/yr from 1999-2018, indicating a -1.72 Gt/yr mass anomaly. This mass loss is driven by synchronous widespread acceleration around Greenland and, like the ice sheet, is primarily caused by changes in discharge from a small number of glaciers with larger discharge. These estimates indicate that although Greenland GICs are small, they are sensitive to changes in climate and should not be overlooked in future analyses of glacier dynamics and mass loss.

Impact of Magnetic Field on the Dynamic Performance of Photovoltaic-Thermal Panel with Nanofluids

The performance of a hybrid solar collector photovoltaic-thermal solar panel system under a magnetic field using nanofluids was presented hereby. A two-dimensional dynamic heat transfer and fluid flow model was developed to describe the behavior of the photovoltaic cell-thermal panel at different conditions such as solar irradiance, nanoparticles, different magnetic field gauss forces. different material properties, and boundary conditions. The model has been established after the dynamic mass and energy equations coupled with the heat transfer relationships, and thermodynamic properties as well as material properties under different magnetic gauss forces. Comparisons were made against literature data for validation purposes of the predictive model. The model fairly predicted the key parameters under different nanofluids conditions, magnetic fields, and compared well with existing data on the subject.

PENGARUH BENTUK GUBAHAN MASSA DINAMIS TERHADAP ESTETIKA DAN KENYAMANAN SPASIAL PADA BANGUNAN HOTEL U JANEVALLA

Hotel is a commercial building and the success of its design has a very positive impact on increasing its selling value. Generally, hotel buildings in cities or city hotels are designed based on the form follow function theory so that the interior space is functioning optimally, but the shape of the square block buildings that occur tends to look monotonous. In order to make the visual appearance more attractive, through the strategy of transforming the mass composition of the hotel to be dynamic, there will be a consequence where the layout and furnishings of the existing interior may reduce the spatial comfort (space) for the user. Another thing that must be tested from a dynamic mass composition is its aesthetic value in terms of proportion and scale. As a research case study, Hotel U Janevalla was chosen in Jl. Aceh No. 65 Bandung. The analysis was carried out in a comparative way between case studies and theory, both in terms of qualitative and quantitative. The benefit value of this research is an insight into how the dynamic mass composition of hotels influences the aesthetic value and spatial comfort of users in the bedroom.Keywords: Hotel, Dynamic mass composition transformation, Aesthetics, Spatial comfort. Abstrak: Hotel adalah bangunan komersial dan keberhasilan desainnya berdampak sangat positif bagi peningkatan nilai jualnya. Umumnya bangunan hotel di kota atau city hotel dirancang berdasarkan teori form follow function agar ruang dalamnya berfungsi optimal, tetapi bentuk bangunan blok persegi yang terjadi cenderung terlihat monoton. Agar tampilan visualnya lebih menarik, melalui strategi transformasi gubahan massa hotel dibuat menjadi dinamis, maka timbul konsekuensi dimana dengan tata letak dan kelengkapan interior yang ada dapat terjadi kemungkinan berkurangnya kenyamanan spasial (ruang gerak) bagi pengguna. Hal lain yang harus diuji dari gubahan massa dinamis adalah nilai estetikanya ditinjau dari proporsi dan skala. Sebagai kasus studi penelitian, dipilih Hotel U Janevalla di Jl. Aceh No. 65 Bandung. Analisis dilakukan dengan cara komparatif antara kasus studi dengan teori, baik ditinjau dengan cara kualitatif maupun kuantitatif. Nilai manfaat dari penelitian ini adalah wawasan bagaimana pengaruh bentuk gubahan massa hotel yang dinamis terhadap nilai estetika dan kenyamanan spasial pengguna pada kamar tidur.Kata Kunci: Hotel, Transformasi gubahan massa dinamis, Estetika, Kenyamanan spasial.