Research poster: Hydrological impacts of climate change on Colorado Basin

Research poste

The Scaling Impact of Hydrologic Processes on the Integrated Response in Large River Basins

21 PowerPoint slides Convener: Darko Koracin, DRI Session 5: Climate Modeling Abstract: -Hydrologic change in response to the climatic variability (i.e., global warming) -Impacts at global, national or regional scales -Coupled, efficient model systems -Large-scale impacts vs. small-scale hydrology -Needs to bridge the gaps among various scale

A Label-Free Platform for Identification of Exosomes from Different Sources.

Exosomes contain cell- and cell-state-specific cargos of proteins, lipids, and nucleic acids and play significant roles in cell signaling and cell-cell communication. Current research into exosome-based biomarkers has relied largely on analyzing candidate biomarkers, i.e., specific proteins or nucleic acids. However, this approach may miss important biomarkers that are yet to be identified. Alternative approaches are to analyze the entire exosome system, either by "omics" methods or by techniques that provide "fingerprints" of the system without identifying each individual biomolecule component. Here, we describe a platform of the latter type, which is based on surface-enhanced Raman spectroscopy (SERS) in combination with multivariate analysis, and demonstrate the utility of this platform for analyzing exosomes derived from different biological sources. First, we examined whether this analysis could use exosomes isolated from fetal bovine serum using a simple, commercially available isolation kit or necessitates the higher purity achieved by the "gold standard" ultracentrifugation/filtration procedure. Our data demonstrate that the latter method is required for this type of analysis. Having established this requirement, we rigorously analyzed the Raman spectral signature of individual exosomes using a unique, hybrid SERS substrate made of a graphene-covered Au surface containing a quasi-periodic array of pyramids. To examine the source of the Raman signal, we used Raman mapping of low and high spatial resolution combined with morphological identification of exosomes by scanning electron microscopy. Both approaches suggested that the spectra were collected from single exosomes. Finally, we demonstrate for the first time that our platform can distinguish among exosomes from different biological sources based on their Raman signature, a promising approach for developing exosome-based fingerprinting. Our study serves as a solid technological foundation for future exploration of the roles of exosomes in various biological processes and their use as biomarkers for disease diagnosis and treatment monitoring

Single Inclusive Jet Production in pApA Collisions at NLO in the small-xx regime

We present the first complete NLO prediction with full jet algorithm implementation for the single inclusive jet production in $pA$ collisions within the CGC effective theory. Our prediction is fully differential over the final state physical kinematics, which allows the implementation of any IR safe observable including the jet clustering procedure. The NLO calculation is organized with the aid of the power counting proposed in [1] which gives rise to the novel soft contributions in the CGC factorization. We achieve the fully-differential calculation by constructing suitable subtraction terms to handle the singularities in the real corrections. The subtraction contributions can be exactly integrated analytically. We present the NLO cross section with the jets constructed using the anti-$k_T$ algorithm. The NLO calculation demonstrates explicitly the validity of the CGC factorization in jet production. Furthermore, as a byproduct of the subtraction method, we also derive the fully analytic cross section for the forward jet production in the small-$R$ limit. We show that in the small-$R$ approximation, the forward jet cross section can be factorized into a semi-hard cross section that produces a parton and the semi-inclusive jet functions. We argue that this feature holds for generic jet production and jet substructure observables in the CGC framework. Last, we show numerical analyses of the derived formula to validate our calculations. We justify when the small-$R$ approximation is appropriate. Like forward hadron production, the obtained NLO result also exhibits the negativity of the cross section in the large jet transverse regime, which signals the need for the threshold resummation. A sketch of the threshold resummation in the CGC framework is presented based on the multiple emission picture.Comment: 67 pages, multiple figures, comments welcome, reference update

Research poster: From lab to basin scale: A Look at changes in evaporative and transpirative processes in arid and semi-arid shallow groundwater systems

Research poste

Geochemical modeling of solubility and speciation of uranium, neptunium, and plutonium

The purpose of this study is to model the solubility, speciation, and transport of three actinides: uranium (U), neptunium (Np), and plutonium (Pu) by a geochemical modeling tool under possible repository environmental conditions upon waste package failure. The dissolution concentration of three actinides in the waste package, their aqueous speciation after dissolving in the unsaturated zone (UZ), and transport processes in the saturated zone (SZ) along the groundwater flow path at Yucca Mountain (YM) are simulated by geochemical modeling calculations using PHREEQC. This model report was prepared in fulfillment of Groundwater Characterization at Yucca Mountain, Task II: Surface Complexation and Solid Phase Dissolution, Subtask 6: Phenomena Modeling of Actinide speciation simulation (Research Foundation Task: ORD-RF-02). This subtask with evaluates of the sensitivity of the current models to solubility data and impact of actinide speciation data on the behavior and mobility of actinide species. For fundamental theory of three concerned actinide species on which the simulation built up, please see Technical Report, “Groundwater Characterization at Yucca Mountain, Task 2: Surface Complexation and Solid Phase Sorption” (Czerwinski, 2007). Uranium, neptunium, and plutonium have been considered to be the most important components in high-level radionuclide wastes (RW) after hundreds of years deposit. The geochemical model includes three sub-models: solubility model, aqueous speciation model, and transport model. Three actinides are programmed separately in each submodel. According to the definition of unqualified data, the third sub-model uses some unqualified data, so the modeling results of transport are considered to be Unqualified (UQ) and are not included in any conclusions. The scope of this model report is to describe the development of a geochemical model for simulating dissolution concentration of three actinides in the waste package, aqueous speciation in UZ directly below the repository, and transport in groundwater system. The three sub-models include: the solubility model, where water may have seeped into the repository from the surrounding rock, percolated into a failed waste package, and reacted with the waste form in the waste package. The second sub-model is the aqueous speciation model, where the dissolved radionuclide-bearing solution exits the waste package via advection and then mixes with pore water in the UZ. The third sub-model is the transport model, where the dissolved radionuclide minerals migrate through the UZ, enters the SZ beneath the groundwater table, and then reaches the 20 km alluvium aquifer down gradient to the southwest of YM. The transport sub-model involved some UQ data; however, the results that come from it are listed only in the Appendix. Source of data for this study are derived from YM Databases, including mineralogy, kinetics, and thermodynamics, which are valid for temperatures up to 100 o C and ionic strength up to 1 molal

Direct experimental evidence for quadruplex–quadruplex interaction within the human ILPR

Here we report the analysis of dual G-quadruplexes formed in the four repeats of the consensus sequence from the insulin-linked polymorphic region (ACAGGGGTGTGGGG; ILPRn=4). Mobilities of ILPRn=4 in nondenaturing gel and circular dichroism (CD) studies confirmed the formation of two intramolecular G-quadruplexes in the sequence. Both CD and single molecule studies using optical tweezers showed that the two quadruplexes in the ILPRn=4 most likely adopt a hybrid G-quadruplex structure that was entirely different from the mixture of parallel and antiparallel conformers previously observed in the single G-quadruplex forming sequence (ILPRn=2). These results indicate that the structural knowledge of a single G-quadruplex cannot be automatically extrapolated to predict the conformation of multiple quadruplexes in tandem. Furthermore, mechanical pulling of the ILPRn=4 at the single molecule level suggests that the two quadruplexes are unfolded cooperatively, perhaps due to a quadruplex–quadruplex interaction (QQI) between them. Additional evidence for the QQI was provided by DMS footprinting on the ILPRn=4 that identified specific guanines only protected in the presence of a neighboring G-quadruplex. There have been very few experimental reports on multiple G-quadruplex-forming sequences and this report provides direct experimental evidence for the existence of a QQI between two contiguous G-quadruplexes in the ILPR

Higher-order Oscillatory Planar Hall Effect in Topological Kagome Metal

Exploration of exotic transport behavior for quantum materials is of great interest and importance for revealing exotic orders to bring new physics. In this Letter, we report the observation of exotic prominent planar Hall effect (PHE) and planar anisotropic magnetoresistivity (PAMR) in strange kagome metal KV$_3$Sb$_5$. The PHE and PAMR, which are driven by an in-plane magnetic field and display sharp difference from other Hall effects driven by an out-of-plane magnetic field or magnetization, exhibit exotic higher-order oscillations in sharp contrast to those following empirical rule only allowing twofold symmetrical oscillations. These higher-order oscillations exhibit strong field and temperature dependence and vanish around charge density wave (CDW) transition. The unique transport properties suggest a significant interplay of the lattice, magnetic and electronic structure in KV$_3$Sb$_5$. This interplay can couple the hidden anisotropy and transport electrons leading to the novel PHE and PAMR in contrast to other materials