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The vadose zone acts as a natural buffer against groundwater contamination, and thus, its attenuation capacity (AC) directly affects groundwater vulnerability to pollutants. A regression model from the previous study predicting the overall AC of soils against diesel was further expanded to the GIS-based overlay-index model. Among the six physicochemical parameters used in the regression model, saturation degree (SD) is notably susceptible to climatological and meteorological events. To accommodate the lack of soil SD historical data, a series of infiltration simulations were separately conducted using Phydrus code with moving boundary conditions (i.e., rainfall records). The temporal variation of SD and the resulting AC under transient conditions are captured by building a space–time cube using a temporal raster across the study area within the designated time frame (1997–2022). The emerging hot spot analysis (EHSA) tool, based on the Getis–Ord Gi* and Mann–Kendall statistics, is applied to further identify any existing pattern associated with both SD and AC in both space and time simultaneously. Under stationary conditions, AC decreases along depth and is relatively lower near water bodies. Similarly, AC cold spot trends also show up near water bodies under transient conditions. The result captures not only the trends across time but also shows the exact location where the changes happen. The proposed framework provides an efficient tool to look for locations that have a persistently low or a gradually decreasing ability to attenuate diesel over time, indicating the need for stricter management regulations from a long-term perspective. [ABSTRACT FROM AUTHOR]

Background and Objectives: To optimally predict lymph node (LN) failure after definite radiotherapy (RT) in head and neck cancer (HNC) with LN metastases, this study examined radiomics models extracted from CT images of different periods during RT. Materials and Methods: This study retrospectively collected radiologic and clinical information from patients undergoing definite RT over 60 Gy for HNC with LN metastases from January 2010 to August 2021. The same largest LNs in each patient from the initial simulation CT (CTpre) and the following simulation CT (CTmid) at approximately 40 Gy were indicated as regions of interest. LN failure was defined as residual or recurrent LN within 3 years after the end of RT. After the radiomics features were extracted, the radiomics alone model and the radiomics plus clinical parameters model from the set of CTpre and CTmid were compared. The LASSO method was applied to select features associated with LN failure. Results: Among 66 patients, 17 LN failures were observed. In the radiomics alone model, CTpre and CTmid had similar mean accuracies (0.681 and 0.697, respectively) and mean areas under the curve (AUC) (0.521 and 0.568, respectively). Radiomics features of spherical disproportion, size zone variance, and log minimum 2 were selected for CTpre plus clinical parameters. Volume, energy, homogeneity, and log minimum 1 were selected for CTmid plus clinical parameters. Clinical parameters including smoking, T-stage, ECE, and regression rate of LN were important for both CTpre and CTmid. In the radiomics plus clinical parameters models, the mean accuracy and mean AUC of CTmid (0.790 and 0.662, respectively) were more improved than those of CTpre (0.731 and 0.582, respectively). Conclusions: Both models using CTpre and CTmid were improved by adding clinical parameters. The radiomics model using CTmid plus clinical parameters was the best in predicting LN failure in our preliminary analyses. [ABSTRACT FROM AUTHOR]

New memory interconnect technology, such as Intel's Compute Express Link (CXL), helps to expand memory bandwidth and capacity by adding CPU-less NUMA nodes to the main memory system, addressing the growing memory wall challenge. Consequently, modern computing systems embrace the heterogeneity in memory systems, composing the memory systems with a tiered memory system with near and far memory (e.g., local DRAM and CXL-DRAM). However, adopting NUMA interleaving, which can improve performance by exploiting node-level parallelism and utilizing aggregate bandwidth, to the tiered memory systems can face challenges due to differences in the access latency between the two types of memory, leading to potential performance degradation for memory-intensive workloads. By tackling the challenges, we first investigate the effects of the NUMA interleaving on the performance of the tiered memory systems. We observe that while NUMA interleaving is essential for applications demanding high memory bandwidth, it can negatively impact the performance of applications demanding low memory bandwidth. Next, we propose a dynamic cache management, called T-CAT, which partitions the last-level cache between near and far memory, aiming to mitigate performance degradation by accessing far memory. T-CAT attempts to reduce the difference in the average access latency between near and far memory by re-sizing the cache partitions. Through dynamic cache management, T-CAT can preserve the performance benefits of NUMA interleaving while mitigating performance degradation by the far memory accesses. Our experimental results show that T-CAT improves performance by up to 17% compared to cases with NUMA interleaving without the cache management. [ABSTRACT FROM AUTHOR]

Summary: High‐Ni layered‐oxide cathodes are the most prospective cathode materials for next‐generation Li‐ion batteries (LIBs) in electric vehicles (EVs) owing to their high specific capacity. However, High‐Ni layered‐oxide cathode materials exhibit inferior cyclability and low thermal stability owing to the side reaction between Ni4+ and the electrolytes. To solve these surface‐related problems, we proposed a strategy for forming LiNbO3 (LNO)—with outstanding thermal stability and ionic conductivity—on a Ni‐rich layered‐oxide surface using polydopamine (PDA). The PDA formed on the transition metal hydroxide surface has copious catechol OH groups, which attract the Nb ions in the solution to form a LNO coating layer during the calcination process. The LiNi0.8Co0.1Mn0.1O2 (pristine LNCM) electrode experiences enormous degradation when cycled after being subjected to severe conditions—such as a full charge and a 60°C storage test—but the LiNbO3‐coated LNCM (LNO‐LNCM) electrode exhibits particularly stable cycling performance. Furthermore, differential scanning calorimetry (DSC) results exhibited that the LNO coating notably ameliorated the thermal stability of the cathode material. As a result, our experimental results suggest that the development of cathode materials that can withstand greatly oxidized states and high‐temperature environments is achievable. [ABSTRACT FROM AUTHOR]

Summary: The formation of Li4SiO4 (LSO) coating layer on LiNi0.88Co0.05Mn0.07O2 (LNCM) was achieved by incorporating a new tetraethyl orthosilicate (TEOS)‐dropping coating method. This concept includes the hydrolysis reaction of TEOS on the surface of Ni0.88Co0.05Mn0.07(OH)2 and the subsequent calcination process with lithium source to obtain LSO‐coated LNCM cathode materials successfully during the calcination process. This method provides the driving force for the formation of a more uniform and thin coating layer compared with the traditional wet‐chemical coating method. The bare LNCM and LSO‐coated LNCM showed similar capacity retention rates during room temperature (25°C) cycling, but the capacity retention of LSO‐LNCM (81.6% after 100 cycles) for the cycling test at elevated temperature was significantly increased compared with bare LNCM (63.69% after 100 cycles). Additionally, the Li‐ion accessibility of the coated LNCM electrode was improved by the existence of the Li‐containing coating materials, and the results of analysis by the galvanostatic intermittent titration technique (GITT) confirmed the better Li‐ion diffusivity of the coated sample. These results indicate the high possibility of this novel coating method for application in various materials for developing secondary batteries. [ABSTRACT FROM AUTHOR]

Various hydrogeochemical processes can modify the quality of river water during riverbank filtration (RBF). Identifying the subsurface processes responsible for the bank-filtered water quality is challenging, but essential for predicting water quality changes and determining the necessity of post-treatment. However, no systematic approach for this has been proposed yet. In this study, the subsurface hydrogeochemical processes that caused the high concentrations of total iron (Fe) and sulfate (SO42−) in the bank-filtered water were investigated at a pilot-scale RBF site in South Korea. For this purpose, water quality variations were monitored in both the extraction well and the adjacent river over five months. The volumetric mixing ratio between the river water and the native groundwater in the RBF well was calculated to understand the effect of mixing on the quality of water from the well and to assess the potential contribution of subsurface reactions to water quality changes. To identify the subsurface processes responsible for the evolution of Fe and SO42− during RBF, an inverse modeling based on the chemical mass balance was conducted using the water quality data and the calculated volumetric mixing ratio. The modeling results suggest that pyrite oxidation by abundant O2 present in an unsaturated zone could be a primary process explaining the evolution of total Fe and SO42− during RBF at the study site. The presence of pyrite in the aquifer was indirectly supported by iron sulfate hydroxide (Fe(SO4)(OH)) detected in oxidized aquifer sediments. [ABSTRACT FROM AUTHOR]

The biodiesel containing fatty acid methyl esters (FAMEs) are blended with refined diesel products. Here, we evaluate relative FAME composition ratio as a potential index to discriminate the pollution origin in diesel-contaminated soil. Artificially contaminated soil was prepared to mimic the release of petroleum products using four different refined diesels; in addition, the contaminated soil was put under natural weathering conditions. The variations in the relative FAME composition ratio was compared with those of the corresponding diesel origin using principal component analysis (PCA) for 60 days. All soil samples could be classified into four groups according to diesel origin using two principal components. The proposed method can be used to discriminate the specific diesel pollution origin in contaminated soils. [ABSTRACT FROM AUTHOR]

Lead (Pb) isotope ratios are commonly used to determine the relative contributions of anthropogenic and geogenic sources to metal contaminations in soils. For successful source apportionment, it is critical to obtain a reliable Pb isotope ratio value for each end member. However, the conventional practice for estimating the geogenic Pb isotope ratio can get affected by the anthropogenic Pb, which might produce misleading results. Therefore, this study proposes a modified approach that enhances the reliability of geogenic Pb isotope ratio estimations. To evaluate the feasibility of the proposed approach, laboratory experiments and field soil sample analyses were conducted. In the laboratory experiments, possible transformation of the metal-binding forms was monitored for a year using soils artificially contaminated with Pb and zinc (Zn). The results indicated that the anthropogenic metals in the soil barely transformed into the residual form, and thus, soil samples without less stable metal forms may better represent the original soil minerals. Field soil samples were collected from a metal-contaminated site near a zinc-smelter and were investigated using both the conventional and modified approaches. The modified method involves collecting multiple soil samples along consecutive depths at a location, chemically leaching out the mobile fractions of metals from the samples and determining the converging value of Pb isotope ratio by comparing subsequent values. The results revealed that the modified method gives the Pb isotope ratios which gradually decrease to a certain depth and then converge to a value. On the other hand, the conventional method shows the irregular vertical distributions of Pb isotope ratios possibly due to the infiltrations of anthropogenic Pb. Finally, the application of the modified approach to the zinc-smelter sites was found to yield more reasonable metal source apportionments. [ABSTRACT FROM AUTHOR]

The importance of stagnation points for characterizing groundwater flow patterns has long been recognized. However, the possible streamline configurations near stagnation points under the constraints of Darcy's law have not been thoroughly investigated. We fill this gap by conducting a systematic analysis of groundwater flow patterns near stagnation points in two and three dimensions. The approach borrows ideas from dynamical systems theory, as often done in fluid mechanics. The most general form of Darcy's law, which applies to variable‐density, compressible fluids flowing through heterogeneous, anisotropic, compressible porous media, is first considered. Under these conditions, there are no major restrictions on the possible flow patterns near stagnation points. The common types of stagnation points are thus minimums (spiral or nonspiral), maximums (spiral or nonspiral), and saddles (in three dimensions, these can be converging or diverging and spiral or nonspiral). The implications of dealing with more restrictive fluid and porous medium properties are then systematically investigated. In particular, important restrictions on the possible types of stagnation points exist when the flow is constant density or divergence free. The theoretical analysis is complemented by a series of examples of groundwater flow fields in which different types of stagnation point arise. The findings highlight key differences between two‐dimensional and three‐dimensional flows and provide new insights on the patterns of variable‐density groundwater flow. The fundamental knowledge on groundwater flow patterns gained from this study will benefit both theoretical and applied studies of groundwater flow and solute transport. Plain Language Summary: Groundwater flow patterns reveal how water flows and solutes are transported in the subsurface. Therefore, characterizing them allows for understanding the origin and fate of water and solutes in the subsurface. Such information is absolutely essential for developing appropriate water resources management strategies. This paper investigates stagnation points in groundwater flow fields, where the flux is zero. Although the flux at these points is zero, these points are extremely important to identify and analyze in order to characterize the flow patterns. The reason is that at stagnation points, groundwater flow can converge, diverge, or abruptly change its course. This is in contrast with other (nonzero flux) points, at which groundwater locally flows uniformly. This article provides for the first time a thorough investigation of the possible flow patterns near stagnation points in porous media in two and three dimensions. It thus advances fundamental knowledge on groundwater flow patterns that will benefit both theoretical and applied studies of groundwater flow and solute transport. Key Points: Flow patterns near stagnation points are systematically studied and classified in general Darcy flow in two and three dimensionsRestrictions on the possible flow patterns near stagnation points are identified depending on fluid and porous medium propertiesDifferent types of stagnation points are illustrated in practical examples of groundwater flow [ABSTRACT FROM AUTHOR]

Iron oxide and oxy-hydroxide are commonly used for remediation and rehabilitation of arsenic (As)-contaminated soil and water. However, the stability of As sequestered by iron oxide and oxy-hydroxide under anaerobic conditions is still uncertain. Geochemical properties influence the behavior of As; in addition, microbial activities affect the mobility of sequestered As in soil and water. Microbial-mediated iron reduction can increase the mobility of As by reductive dissolution of Fe oxide; however, microbial-mediated sulfate reduction can decrease the mobility of As by sulfide mineral precipitation. This study investigated the geomicrobial impact on the behavior of As and stability of sequestered As in iron-rich sediment under anaerobic conditions. Increase in Fe(II) concentrations in water was evidence of microbial-mediated iron reduction. Arsenic concentrations increased with Fe(II) concentration; however, the thiosulfate reduction process also induced immobilization of As through the precipitation of AsFeS. Therefore, microbial-mediated iron reduction and thiosulfate reduction have opposite influences on the mobility of As under anaerobic condition. [ABSTRACT FROM AUTHOR]

In order to solve large-scale lasso problems, screening algorithms have been developed that discard features with zero coefficients based on a computationally efficient screening rule. Most existing screening rules were developed from a spherical constraint and half-space constraints on a dual optimal solution. However, existing rules admit at most two half-space constraints due to the computational cost incurred by the half-spaces, even though additional constraints may be useful to discard more features. In this paper, we present AdaScreen, an adaptive lasso screening rule ensemble, which allows to combine any one sphere with multiple half-space constraints on a dual optimal solution. Thanks to geometrical considerations that lead to a simple closed form solution for AdaScreen, we can incorporate multiple half-space constraints at small computational cost. In our experiments, we show that AdaScreen with multiple half-space constraints simultaneously improves screening performance and speeds up lasso solvers. [ABSTRACT FROM AUTHOR]

We examined the potential of photosynthetic microalgae to perform anaerobic transformation of an energetic explosive compound, hexahydro‐1,3,5‐trinito‐1,3,5‐triazine (RDX). All species tested, including Microcystis sp., Pediastrum biwae, Nostoc commune, and Scenedesmus obliquus, exhibited the potential for RDX transformation under light and initially anaerobic conditions; 40 µM (∼ 8.9 mg L−1) of RDX decreased to 0∼7 µM within 7 d. The formation and subsequent removal of nitrite and ammonium occurred after RDX transformation in the presence of S. obliquus under light and anaerobic conditions. Significantly more RDX was transformed when incubated with S. obliquus than without microalgae, likely because the cells used RDX and its metabolites as carbon and nitrogen sources. In the absence of microalgae, RDX concentrations decreased by <5%, 40%, and 75% at light intensities of 0, 25, and 50 µmol s−1 m−2, respectively, within 15 d, and nitrite as a byproduct of RDX transformation was detected only under light conditions. This suggested that RDX transformation occurred not only by enzymatic transformation but also through an initial denitration pathway via photodegradation. This study demonstrates that photosynthetic microalgae can transform RDX and its intermediates effectively under light and anaerobic conditions, and suggests that photosynthetic microalgae are a viable option for treating RDX‐contaminated wastewater. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 1677–1683, 2018 [ABSTRACT FROM AUTHOR]

We investigated the source of heavy metals in soils at a site in South Korea, where a ground transportation of zinc-concentrates (ZnS, sphalerite) occurs daily. Seventy soil samples were collected at the site and analyzed for residual concentrations of heavy metals, as well as their chemical and mineralogical properties. Enrichment factor was calculated based on local geochemical background level of metals in soils and confirmed the contamination of soils in the area by an anthropogenic source. The concentration data were also subjected to a Pearson correlation analysis to determine the possible influences of anthropogenic sources and identify the primary source. A slight negative correlation between heavy metals and Al, and a weak correlation between heavy metals and Fe implied that the heavy metals originated from anthropogenic inputs rather than a geogenic source. A strong positive linear correlation between Zn and other heavy metals (i.e., As, Cd, Cu, Pb, r ≥ 0.96, p ≤ 0.001) suggested the influence of a single anthropogenic source of zinc-concentrates containing all of these heavy metals. Zinc-concentrate oxidation and leaching experiments, which mimicked physical and chemical weathering in the environment, indicated that zinc-concentrate could be transformed to zinc oxides and release Cd and Pb upon precipitation. The findings in this study provide an insight into the fate of the Zn that the original form of zinc-concentrate would not remain in the soil after long-term weathering, which should be considered when source of heavy metals is identified. [ABSTRACT FROM AUTHOR]

Managing recharge of freshwater into saline aquifers requires accurate estimation of the heterogeneous permeability field for maximizing injection and recovery efficiency. Here we present a methodology for subsurface characterization in saline aquifers that takes advantage of the density difference between the injected freshwater and the ambient saline groundwater. We combine high-resolution forward modeling of density-driven flow with an efficient Bayesian geostatistical inversion algorithm. In the presence of a density difference between the injected and ambient fluids due to differences in salinity, the pressure field is coupled to the spatial distribution of salinity. This coupling renders the pressure field transient: the time evolution of the salinity distribution controls the density distribution which then leads to a time-evolving pressure distribution. We exploit this coupling between pressure and salinity to obtain an improved characterization of the permeability field without multiple pumping tests or additional salinity measurements. We show that the inversion performance improves with an increase in the mixed convection ratio-the relative importance between viscous forces from injection and buoyancy forces from density difference. Our work shows that measuring transient pressure data at multiple sampling points during freshwater injection into saline aquifers can be an effective strategy for aquifer characterization, key to the successful management of aquifer recharge. [ABSTRACT FROM AUTHOR]

Hydrocarbons found in the environment are typically characterized by gas chromatography (GC). The shape of the GC chromatogram has been used to identify the source of petroleum contamination. However, the conventional practice of simply comparing the peak patterns of source products to those of environmental samples is dependent on the subjective decisions of individual analysts. We have developed and verified a quantitative analytical method for interpreting GC chromatograms to distinguish refined petroleum products in contaminated soils. We found that chromatograms for gasoline, kerosene, and diesel could be divided into three ranges with boundaries at C, C, C, and C. In addition, the relative peak area (RPA) of each range, a dimensionless ratio of the peak area within each range to that of the total range (C-C), had a unique value for each petroleum product. An identification index for GC chromatograms (ID), defined as the ratio of RPA of C-C to that of C-C, was able to identify diesel and kerosene sources in samples extracted from artificially contaminated soils even after weathering. Thus, the ID can be used to effectively distinguish between refined petroleum products in contaminated soils. [ABSTRACT FROM AUTHOR]

The sorption properties of TiO nanoparticles (NPs) on sand were investigated in the presence of Suwannee River humic acid (SRHA) as a surrogate for natural organic matter. SRHA drastically reduced the sorption preference regardless of the initial pH and ionic strength of the solution. Despite the higher SRHA loading onto sand versus the TiO NPs, the consequent zeta ( ζ)-potential drop was more significant in the TiO NPs, indicating that the decreased sorption should be primarily ascribed to the fraction of SRHA sorbed onto the TiO NP surfaces. The hindering effect of SRHA on the sorption increased with SRHA concentration, but stabilized at the concentration equivalent to full surface coverage of the TiO NPs and sand in the reaction system. Interaction force measurements indicated that SRHA inhibits the approach of the TiO NPs to the sand surface, as expected by the Derjaguin-Landau-Verwey-Overbeek calculation. However, the adhesion force of TiO NPs to sand was not critically affected by the presence of SRHA. TiO NP sorption to natural sand was limited as to the acid-treated sand in the presence of SRHA, implying that the organics dissolved from natural sand might facilitate the transport of TiO NPs in aquifers by inhibiting TiO NP sorption to aquifer materials. [ABSTRACT FROM AUTHOR]

The ultimate goal of our study is to establish thin-layer chromatography (TLC) as a quick and simple method for identifying the type of refined petroleum products present in the environmental media. As a preliminary step, TLC chromatograms of different petroleum products, including gasoline, kerosene, and diesel, were characterized and compared. Methanol was determined as the optimum carrier solution in TLC analysis. The spherical-shaped TLC chromatogram of gasoline showed the longest migration distance, and thus the highest retardation factor ( R ) of 0.91. This was followed by that of kerosene (0.63) with an elliptical-shaped, and diesel (0.24) with an elongated trapezoid-shaped chromatogram. R of kerosene and diesel increased with the dilution factor, while gasoline showed a constant value. Additionally, it was observed that the TLC chromatograms of oils produced the same peak pattern with the corresponding petroleum products in gas chromatography (GC). A mixed sample of kerosene and diesel presented a triangular shaped chromatogram, underlining the need to consider the shape of chromatogram in addition to the R value, as an indicator of the petroleum type. The findings indicate that TLC has a huge potential to be used as a quick and reliable method for identifying the type of refined petroleum products in the environmental media. [ABSTRACT FROM AUTHOR]

To remove phosphate from solution, a new class of sorbent based on chitosan bead (CB) was prepared using copper ion (Cu(II)) with/without a traditional crosslinking agent (glutaraldehyde [GLA]); these materials are referred to as CB-G-Cu and CB-Cu, respectively. Copper ions play a key role in the CB synthesis; these species crosslink each polymer chain, and during phosphate removal, they are the active functional group. Overall, 2.5 % (w/w) of chitosan is necessary to maintain the physical properties of the bead. In the FTIR spectra, adding GLA decreased the intensity of the amino group in chitosan, lowering the amount of copper in the CB. The maximum phosphate uptake ( Q) for CB-Cu was 53.6 mg g when calculated with the Langmuir isotherm, and the phosphate equilibrium was achieved in 12 h. Although the solution pH was not strongly affected, values below 7 are optimal for phosphate removal. The CB-Cu can be feasibly applied during a fixed column test, revealing that the phosphate breakthrough was 1.5 times higher than with CB-G-Cu. [ABSTRACT FROM AUTHOR]

With the continuous improvement in genotyping and molecular phenotyping technology and the decreasing typing cost, it is expected that in a few years, more and more clinical studies of complex diseases will recruit thousands of individuals for pan-omic genetic association analyses. Hence, there is a great need for algorithms and software tools that could scale up to the whole omic level, integrate different omic data, leverage rich structure information, and be easily accessible to non-technical users. We present GenAMap, an interactive analytics software platform that 1) automates the execution of principled machine learning methods that detect genome- and phenome-wide associations among genotypes, gene expression data, and clinical or other macroscopic traits, and 2) provides new visualization tools specifically designed to aid in the exploration of association mapping results. Algorithmically, GenAMap is based on a new paradigm for GWAS and PheWAS analysis, termed structured association mapping, which leverages various structures in the omic data. We demonstrate the function of GenAMap via a case study of the Brem and Kruglyak yeast dataset, and then apply it on a comprehensive eQTL analysis of the NIH heterogeneous stock mice dataset and report some interesting findings. GenAMap is available from http://sailing.cs.cmu.edu/genamap. [ABSTRACT FROM AUTHOR]

This paper presents an implementation of a 2 × 2 Multi-Input Multi-Output Software Defined Radio (SDR) Base Station system using a Message Passing Interface (MPI)-based Graphic Processing Unit (GPU) cluster as its modem processor for a high-speed data processing. Recently, GPUs have been widely researched especially for SDR systems because of their capability for exploiting parallel processing using a large number of Arithmetic Logic Units. MPI-based GPU clusters have been adopted in order to further increase performance capability. From our experimental results, it has been found that the implemented system consisting of three GPU nodes can enhance the modem speed by more than 2.5 times compared to a single GPU system. A dual-mode Mobile Device (MD) prototype supporting Worldwide Interoperability for Microwave Access and Long Term Evolution communications systems is implemented. In our design, one of the two waveforms can automatically be selected by the MD itself using a dual-mode controller that determines the reconfiguration of the MD modem depending on the received signal quality. [ABSTRACT FROM AUTHOR]

Three commercial organoclays were evaluated as media for a variably permeable reactive barrier (VPRB) to manage coal-tar creosote, a non-aqueous-phase liquid (NAPL) consisting primarily of polynuclear aromatic hydrocarbons (PAHs). Organoclays and organoclay-sand mixtures having at least 25% organoclay had NAPL conductivities of less than 10-10 m/s, whereas hydraulic conductivities to water were on the order of 0.001 m/s. Water migration was negligible in organoclays solvated with NAPL, but PAHs were released to the aqueous phase when the solvated clay contacted deionized water. Sorption isotherms for aqueous-phase PAHs are convex upward within the range of concentrations of environmental interest, and greater sorption occurs when the aqueous phase contains multiple PAHs. In column tests, breakthrough occurred for only naphthalene (lowest Kow) and for only one organoclay (lowest organic carbon content) for tests on 100% organoclay and organoclay-sand mixtures conducted for 208-276 pore volumes of flow (PVF). Breakthrough predicted with solute transport analyses conducted using batch isotherm parameters as input occurred later than observed in the column test because isotherm models fit to the batch test data overpredicted sorption at low concentrations. The findings indicate that organoclays should be effective media for VPRBs to manage creosote NAPL and associated PAHs dissolved in groundwater. They block NAPL advection, readily permit the flow of water with dissolved PAHs, and sorb dissolved PAHs from water flowing through the clays. [ABSTRACT FROM AUTHOR]

Simple Summary: Unique responses such as hyperprogressive disease (HPD) and a dissociated response (DR) have been reported after immune checkpoint inhibitor (ICI) treatment, and these patterns are difficult to evaluate with conventional methods. The aim of this study was to evaluate radiomics features of HPD at the lesion level, and to understand the clinical significance of a dissociated response. Our study revealed organ-specific radiomics features, likely reflecting the organ-specific microenvironment, that can be used to discriminate HPD. In addition, we observed that a dissociated response was associated with poor overall survival. A radiomic lesion-level approach shows great potential for response evaluation of ICI treatment. Conventional methods to determine the response to immune checkpoint inhibitors (ICIs) are limited by the unique responses to an ICI. We performed a radiomics approach for all measurable lesions to identify radiomic variables that could distinguish hyperprogressive disease (HPD) on baseline CT scans and classify a dissociated response (DR). One hundred and ninety-six patients with advanced lung cancer, treated with ICI monotherapy, who underwent at least three CT scans, were retrospectively enrolled. For all 621 measurable lesions, HPDv was determined from baseline CT scans using the tumor growth kinetics (TGK) ratio, and radiomics features were extracted. Multivariable logistic regression analysis of radiomics features was performed to discriminate DR. Radiomics features that significantly discriminated HPDv on baseline CT differed according to organ. Of the 196 patients, 54 (27.6%) had a DR and 142 (72.4%) did not have a DR. Overall survival in the group with a DR was significantly inferior to that in the group without a DR (log rank test, p = 0.04). Our study shows that lesion-level analysis using radiomics features has great potential for discriminating HPDv and understanding heterogeneous tumor progression, including a DR, after ICI treatment. [ABSTRACT FROM AUTHOR]

Previous studies have revealed that the application of zero-valent iron (ZVI) in reducing nitrate is limited by ammonium production and the requirement for adequate pH control. The current study focused on developing a new material potentially applicable in permeable reactive barriers, which can reduce nitrate without ammonium release under unbuffered pH. The new material, referred to as ZanF, is derived from zeolite modified by Fe(II), followed by borohydride reduction. The pseudo-first-order rate constant (kobs) of ZanF in the early period of nitrate reduction was 10 times higher than that of the ZVI used in this study. However, the kobs of ZanF decreased in the reaction period that followed. Even though both ZVI and ZanF produced ammonium as a product of nitrate reduction, ZanF removed it to below detection limits via adsorption, whereas ZVI did not remove it to any significant extent. ZanF maintained its high reactivity even under an initial pH of 6.2 without buffer. The higher ZanF/solution ratio increased the removal rate of ZanF as well as the removal efficiency. [ABSTRACT FROM AUTHOR]

A letter to the editor on mixture of distributions indel locator (MoDIL) is presented.

Motivation: As many complex disease and expression phenotypes are the outcome of intricate perturbation of molecular networks underlying gene regulation resulted from interdependent genome variations, association mapping of causal QTLs or expression quantitative trait loci must consider both additive and epistatic effects of multiple candidate genotypes. This problem poses a significant challenge to contemporary genome-wide-association (GWA) mapping technologies because of its computational complexity. Fortunately, a plethora of recent developments in biological network community, especially the availability of genetic interaction networks, make it possible to construct informative priors of complex interactions between genotypes, which can substantially reduce the complexity and increase the statistical power of GWA inference.Results: In this article, we consider the problem of learning a multitask regression model while taking advantage of the prior information on structures on both the inputs (genetic variations) and outputs (expression levels). We propose a novel regularization scheme over multitask regression called jointly structured input–output lasso based on an ℓ1/ℓ2 norm, which allows shared sparsity patterns for related inputs and outputs to be optimally estimated. Such patterns capture multiple related single nucleotide polymorphisms (SNPs) that jointly influence multiple-related expression traits. In addition, we generalize this new multitask regression to structurally regularized polynomial regression to detect epistatic interactions with manageable complexity by exploiting the prior knowledge on candidate SNPs for epistatic effects from biological experiments. We demonstrate our method on simulated and yeast eQTL datasets.Availability: Software is available at http://www.sailing.cs.cmu.edu/.Contact: epxing@cs.cmu.edu [ABSTRACT FROM PUBLISHER]