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Wet snow is a critical component of the cryosphere, and its spatial and temporal distribution has important implications for water resources, natural hazards, and the regional climate. However, mapping wet snow in alpine regions such as the Karakoram is challenging due to complex topography, harsh weather conditions, and limited in-situ observations.Previous studies have shown that synthetic aperture radar (SAR) can effectively detect wet snow surfaces using the backscattering ratio between the current and reference images (e.g. the average of summer acquisitions). However, its regional application on a large-scale and complex terrain is hampered, as the ratio value is easily affected by the land cover, local topography, surface roughness, and snow wetness.In this study, we present a new approach for mapping wet snow in the Karakoram using a combination of SAR data and topographic information. The SAR data used in the analysis were obtained from Sentinel-1, and the topographic data included a digital elevation model (DEM), slope angle, and slope aspect ratio. We first used a Gaussian Mixture Model to classify the ratio image of Sentinel-1 into wet snow (WS) and non-wet snow (NWS) classes, then transformed the two classes into a logistic function to characterize the probability of WS based on the backscattering ratio. Secondly, we categorized the image based on the topography and calculated the likelihood of WS for each topographic bin using the WS probability. The joint WS likelihood map was finally obtained by multiplying the WS probability on the backscattering ratio with the WS likelihood on topography, and a binary WS map was generated by setting a threshold on the joint likelihood map.The proposed method was validated using snow maps generated from Sentinel-2 images. Compared with the traditional method of using only the SAR backscattering ratio, our method significantly reduced false negative detections and preserved the high true positive rate, indicating an improvement of robustness and accuracy by combining SAR and topographic data for regional wet snow mapping.This study demonstrates a practical method of merging SAR backscattering features and topographic information for robust regional wet snow mapping in complex mountain ranges. It also provides new insights into the incorporation of different datasets using a probabilistic framework. With the proposed method, the operational monitoring of wet snow distribution in the Karakoram using SAR becomes feasible and reliable.

Galectin-3 is a 31-kDa lectin that modulates T-cell responses through several mechanisms, including apoptosis, T-cell receptor (TCR) cross-linking, and TCR downregulation. We found that patients with pancreatic ductal adenocarcinoma (PDA) who responded to a granulocyte-macrophage colony-stimulating factor–secreting allogeneic PDA vaccine developed neutralizing antibodies to galectin-3 after immunization. We show that galectin-3 binds activated antigen-committed CD8+ T cells only in the tumor microenvironment. Galectin-3–deficient mice exhibit improved CD8+ T-cell effector function and increased expression of several inflammatory genes. Galectin-3 binds to LAG-3, and LAG-3 expression is necessary for galectin-3–mediated suppression of CD8+ T cells in vitro. Lastly, galectin-3–deficient mice have elevated levels of circulating plasmacytoid dendritic cells, which are superior to conventional dendritic cells in activating CD8+ T cells. Thus, inhibiting galectin-3 in conjunction with CD8+ T-cell–directed immunotherapies should enhance the tumor-specific immune response. Cancer Immunol Res; 3(4); 412–23. ©2015 AACR.

MYPT1 and PSMC5 expression in 3 different subtypes (basal, HER-2 positive and ER positive) of breast cancer.

Predicted activation of TNFα, IFNγ, and IL-6 signaling pathways in the KO/KO CD8+ T cells vs. WT/WT CD8+ T cells. Analyses was conducted using Ingenuity IPA software.

Western blots showing the antibody responses for PSMC5, MYPT1 and TFRC in patients with greater than and less than 3 years disease free survival

Selection criteria used to narrow the proteins identified in the screen to those shown in this study.

Pancreatic cancer is the fourth leading cause of cancer-related deaths in the United States. Less than 6% of patients survive beyond the fifth year due to inadequate early diagnostics and ineffective treatment options. Our laboratory has developed an allogeneic, granulocyte-macrophage colony-stimulating factor (GM-CSF)–secreting pancreatic cancer vaccine (GVAX) that has been tested in phase II clinical trials. Here, we employed a serum antibodies–based SILAC immunoprecipitation (SASI) approach to identify proteins that elicit an antibody response after vaccination. The SASI approach uses immunoprecipitation with patient-derived antibodies that is coupled to quantitative stable isotope–labeled amino acids in cell culture (SILAC). Using mass spectrometric analysis, we identified more than 150 different proteins that induce an antibody response after vaccination. The regulatory subunit 12A of protein phosphatase 1 (MYPT1 or PPP1R12A), regulatory subunit 8 of the 26S proteasome (PSMC5), and the transferrin receptor (TFRC) were shown to be pancreatic cancer–associated antigens recognized by postvaccination antibodies in the sera of patients with favorable disease-free survival after GVAX therapy. We further interrogated these proteins in over 80 GVAX-treated patients' pancreases and uniformly found a significant increase in the expression of MYPT1, PSMC5, and TFRC in neoplastic compared with non-neoplastic pancreatic ductal epithelium. We show that the novel SASI approach can identify antibody targets specifically expressed in patients with improved disease-free survival after cancer vaccine therapy. These targets need further validation to be considered as possible pancreatic cancer biomarkers. Cancer Immunol Res; 4(3); 225–33. ©2016 AACR.

Venn diagram showing overlap of proteins identified in 3 patients after the SASI screen.

Additional immunohistochemical validation showing PSMC5, MYPT1 and TFRC expression in an independent set of pancreatic cancers.

Tumor infiltrating lymphocytes (TIL) were isolated 5 days post adoptive transfer according to the materials and methods section. Cells were gated for Thy1.2 expression. A) Galectin-3 wildtype (WT) high avidity CD8+ T cells were adoptively transferred into either galectin-3 WT (red) or galectin-3 KO neu-N (blue) recipient mice. Histogram overlays show differences in galectin-3 MFI between the two groups with respect to isotype control staining (orange). B) Galectin-3 staining is now shown on galectin-3 KO high avidity CD8+ T cells adoptively transferred into a galectin-3 KO neu-N recipient (blue) with respect to an isotype control (red). C) TCR avidity is compared between galectin-3 WT high avidity CD8+ T cells from a galectin-3 WT neu-N recipient and galectin-3 KO high avidity CD8+ T cells from a galectin-3 KO neu-N recipient. TCR avidity was assessed by staining with a 1:100 dilution of MHC I Dq tetramer loaded with the RNEU420-429 (P50) peptide. This experiment was repeated twice with similar results. D) Histogram overlays demonstrating differences in surface galectin-3 MFI on adoptively transferred high avidity tumor specific CD8+ T cells (Thy1.2+) vs. endogenous CD8+ T cells in the tumor microenvironment (Thy1.2-)

Immune escape is an important reason why the immune system cannot control tumor growth, but how escape variants emerge during immunotherapy remains poorly understood. Here, we identify a new mechanism of tumor immune escape using an in vivo selection strategy. We generated a highly immune-resistant cancer cell line (P3) by subjecting a susceptible cancer cell line (P0/TC-1) to multiple rounds of in vivo immune selection. Microarray analysis of P0 and P3 revealed that vascular cell adhesion molecule-1 (VCAM-1) is up-regulated in the P3-resistant variant. Retroviral transfer of VCAM-1 into P0 significantly increased its resistance against a vaccine-induced immune response. Analysis of tumors showed a dramatic decrease in the number of tumor-infiltrating cluster of differentiation 8+ (CD8+) T cells in the tumors expressing VCAM-1. In vitro transwell migration assays showed that VCAM-1 can promote the migration of CD8+ T cells through its interaction with the α4β1 integrin. Site-directed mutagenesis of VCAM-1 at amino acid residues required for interaction with α4β1 integrin completely abolished the immune resistance conferred by VCAM-1 in vivo. Surface staining showed that most renal cell carcinomas (RCC) express VCAM-1, whereas an RCC that responded to vaccination was VCAM-1 negative. These data provide evidence that tumor expression of VCAM-1 represents a new mechanism of immune evasion and has important implications for the development of immunotherapy for human RCC. [Cancer Res 2007;67(4):1832–41]

Supplementary Figure 3 from Ectopic Expression of Vascular Cell Adhesion Molecule-1 as a New Mechanism for Tumor Immune Evasion

Supplementary Figure 2 from Ectopic Expression of Vascular Cell Adhesion Molecule-1 as a New Mechanism for Tumor Immune Evasion

Supplementary Figure 1 from Ectopic Expression of Vascular Cell Adhesion Molecule-1 as a New Mechanism for Tumor Immune Evasion

Sea ice elevation plays a crucial role in sea ice dynamic processes driven by winds and waves, for which satellite radar remote sensing becomes indispensable to monitor snow-covered sea ice across the vast polar regions regardless of darkness and clouds. To measure sea ice elevation, a theory of polarimetric interferometry for both monostatic and bistatic radars is developed based on analytic solutions of Maxwell's equations, accounting for realistic and complicated properties of snow, sea ice, and seawater. This analytic method inherently preserves phase information that is imperative for radar polarimetry and interferometry. Among a multitude of complex radar coefficients in the general polarimetric interferometric covariance matrix, the symmetry group theory is utilized to identify and select appropriate terms pertaining to the retrieval of sea ice elevation while avoiding radar parameters that may inadvertently introduce non-uniqueness and excessive uncertainty. Theoretical calculations compare well with field observations for rough and old sea ice encountered in the Operation-IceBridge and TanDEM-X Antarctic Science Campaign over the Western Weddell Sea. The results show that the magnitude of the coefficient of normalized correlation between co-polarized horizontal and co-polarized vertical radar returns is inversely related to sea ice elevation, while the associate phase term is nonlinear and noisy and should be excluded. From these analyses, a protocol is set up to measure Antarctic sea ice elevation to be presented in the next companion paper., Earth and Space Science, 9 (5), ISSN:2333-5084

In the problem of aircraft detection for High resolution (HR) Synthetic aperture radar (SAR) images, the background areas commonly contain multiple land cover types, such as runways and grassland. The conventional Constant false alarm rate (CFAR) detection in these non-homogeneous backgrounds with homogeneous assumption leads to unreliable detection results. This paper constructs a one-stage detection method based on the Generalized gamma mixture distribution (GGMD), which is regarded as a competitive and applicable model for combining the advantages of the Generalized gamma distribution (GGD) and the Finite mixture model (FMM). In order to evaluate the availability of the proposed algorithm, HR SAR images for aircraft detection from different product types and with various resolutions are examined. Compared with the CFAR algorithms based on the Gamma distribution, the GGD, and the gamma mixture distribution, the proposed algorithm demonstrates its availability and effectiveness for aircraft detection in HR SAR images in non-homogeneous background.

A novel physical paradigm is explored in this paper: synthetic-aperture radar (SAR) ocean speckle is informative. This paper experimentally analyzes the SAR ocean speckle intensity K-distribution model versus sea-surface wind field. It is shown that the normalized intensity moments of the K-distribution measured from actual C-band SAR data well fit the theoretical ones under different wind conditions, i.e., wind regime and relative SAR-wind azimuth direction. In addition, it is observed that the K-distribution shape parameter decreases as wind speed increases. A sensitivity of the K-distribution shape parameter on incidence angle and wind direction is also observed, where the largest variability is experienced at higher incidence angles and under crosswind relative azimuth angle.

Underwater robot is essential equipment for exploring the marine environment. It is important that children get exposed to these technologies as earlier as possible, especially there is a high demand for developing expertise and awareness in the underwater robot. Although examples of making toolkit for children currently exist, few focus specifically on integration with the water environment. In this paper, we explore the making toolkit, ModBot, which can be applied to the water environment. The hardware was developed using electronic, counterweight, and shape modules that can be manipulated to build underwater robots. The software application allows children to learn concepts and receive construction feedback. This paper presents the system design of ModBot, the design rationale, and a user study for the usability of ModBot. Our system is expected to spark children's interests and creativity of underwater robots, and foster their understanding of the water environment.

Single-pass interferometric synthetic aperture radar (InSAR) is an effective technique for sea ice topographic retrieval despite the inherent dynamics of sea ice. However, the penetration of microwaves into snow-covered thick ice and the achievable height sensitivity for tens-of-centimeters thin ice are two major issues, which limit the accuracy of InSAR-derived sea ice topography. Polarimetry provides scattering information concerning the sea ice properties and has the potential, in combination with interferometry, to achieve an accurate reconstruction of a sea ice digital elevation model (DEM). This article studies the relation between polarimetric signatures and sea ice topography, and explores the possibility to compensate the penetration bias by merging copolar coherence into InSAR processing. The newly generated topographic map has a root-mean-square error under 0.3 m. For thin ice below 1 m, a positive relation between copolar phase phi(coPol) and surface height is observed, suggesting that fcoPol can effectively characterize thin sea ice topography. For thick ice with ridges, the maximum polarimetric phase difference Delta phi(maxPol) reveals a particular shape of the coherence region, which can be interpreted as oriented volume scattering. It suggests that the model-based approach using polarimetric SAR interferometry assuming an oriented volume scattering model is promising in measuring the scattering centers in thick and deformed sea ice. The study of polarimetric behavior for the InSAR DEM is, therefore, a step forward toward accurate modeling of sea ice topography from polarimetric single-pass InSAR data., IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 14, ISSN:1939-1404, ISSN:2151-1535

Magnetic field induced rearrangement of magnetic nanoparticles was observed using synchrotron small-angle X-ray scattering methods., Superparamagnetic nanoparticles have broad applications in biology and medicines. Quantitative measurements of magnetic beads in solution are essential in gaining comprehensive understanding of their dynamics and developing applications. Here, using synchrotron X-ray sources combined with well controlled magnetic fields, the results from small-angle X-ray scattering (SAXS) experiments on superparamagnetic particles in solution under the influence of external magnetic fields are reported. The particles mostly remain in monodispersed states and the linear aggregates tend to be aligned with the external magnetic field. After removing the magnetic fields, the superparamagnetic nanoparticles quickly recover to their original states indicating high reversibility of the rearrangement under the control of a magnetic field. The external magnetic field instrument composed of paired permanent magnets is integrated into the SAXS beamline at the Shanghai Synchrotron Radiation Facility providing a platform for studying time-resolved dynamics induced by magnetic fields.

In this study, synthetic aperture radar ocean speckle is exploited to infer information on sea surface wind field. The K-distribution is adopted to model the single look complex vertically/vertically-polarized intensity speckle signal measured over sea surface under different wind conditions, i. e., wind speed and direction. Experiments undertaken on a large set of Sentinel-1 SAR data collected over the northeastern part of the Atlantic ocean, between southern Iceland and northern Scotland, showed that the shape parameter of the K-distribution is sensitive to both ocean wind field and SAR imaging parameters. In particular, it was shown that the shape parameter decreases when increasing wind speed while its variability becomes significant under crosswind relative azimuth angle and at larger incidence angles.

In this paper, a new simple and effective methodology, based on the K–distribution statistical modeling of speckle over sea surface backscattering, is applied on a large dataset of single– look complex (SLC) VV–polarized C–band Sentinel–1 SAR scenes to evaluate the sensitivity of speckle–related parameters, i. e., the K–distribution shape parameter ν, on sea surface wind field. The proposed approach is validated through the time/space co– location of scatterometer winds and precipitation data that are used as reliable source of wind field information.Experimental results show that the K-distribution is suitable to model sea surface speckle and that the latter is informative, i. e., it can be considered as a proxy of sea surface wind speed.

CXCR1, a member in G-protein coupled receptor (GPCR) family, binds to chemokine interleukin-8 (IL-8) specifically and transduces signals to mediate immune and inflammatory responses. Despite the importance of CXCR1, high-resolution structure determination is hindered by the challenges in crystallization. It has been shown that properly designed mutants with enhanced thermostability, together with fusion partner proteins, can be useful to form crystals for GPCR proteins. In this study, in silico protein design was carried out by using homology modeling and molecular dynamics simulations. To validate the computational modeling results, the thermostability of several mutants and the wild type were measured experimentally. Both computational results and experimental data suggest that the mutant L126W has a significant improvement in the thermostability. This study demonstrated that in silico design can guide protein engineering and potentially facilitate protein crystallography research.

A new study based on the complex and amplitude cross-pol correlation is made. It exploits Sentinel-1 Single Look Complex (SLC) SAR and reference HSCAT wind data. The behavior of these two polarimetric features vs wind speed is analyzed. Low-to-moderate and high wind speed regimes are considered. The study is focused on three subsets characterized by different incident angle ranges. The study shows that in all cases the two polarimetric features are sensitive to wind speed and better behave with respect to $S$ vv .