Category Archives: Science & Technology

Topics such as cyber security, severe weather, space, Earth, oceans, and scientific research.

Joomla! Releases Security Update

Original release date: July 25, 2017

Joomla! has released version 3.7.4 of its Content Management System (CMS) software to address several vulnerabilities. A remote attacker could exploit some of these vulnerabilities to take control of an affected website.

US-CERT encourages users and administrators to review the Joomla! Security Release and US-CERT’s Alert on Content Management Systems Security and Associated Risks and apply the necessary update.

This product is provided subject to this Notification and this Privacy & Use policy.

NSF Research Traineeship program makes 17 new awards

Allyson Ettinger helps lead a session at an NRT-supported workshop.

A National Science Foundation (NSF) program recently awarded 17 projects a total of $51 million to develop and implement bold, new, potentially transformative models for graduate education in science, technology, engineering and mathematics (STEM) fields.

The NSF Research Traineeship (NRT) program awarded projects in high-priority, interdisciplinary research areas, including six projects in NSF’s Innovations at the Nexus of Food, Energy and Water Systems (INFEWS) research initiative

More at

This is an NSF News item.

Laboratory and field based evaluation of chromatography related performance of the Monitor for Aerosols and Gases in Ambient Air (MARGA)

The Monitor for AeRosols and GAses in ambient air (MARGA) is an on-line ion-chromatography-based instrument designed for speciation of the inorganic gas and aerosol ammonium-nitrate-sulfate system. Previous work to characterize the performance of the MARGA has been primarily based on field comparison to other measurement methods to evaluate accuracy. While such studies are useful, the underlying reasons for disagreement among methods are not always clear. This study examines aspects of MARGA accuracy and precision specifically related to automated chromatography analysis. Using laboratory standards, analytical accuracy, precision, and method detection limits derived from the MARGA chromatography software are compared to an alternative software package (Chromeleon, Thermo Scientific Dionex). Field measurements are used to further evaluate instrument performance, including the MARGA’s use of an internal LiBr standard to control accuracy. Using gas/aerosol ratios and aerosol neutralization state as a case study, the impact of chromatography on measurement error is assessed.

Estimating Likelihood of Fetal In Vivo Interactions Using In Vitro HTS Data (Teratology meeting)

Tox21/ToxCast efforts provide in vitro concentration-response data for thousands of compounds. Predicting whether chemical-biological interactions observed in vitro will occur in vivo is challenging. We hypothesize that using a modified model from the FDA guidance for drug interaction studies, Cmax/AC50 (i.e., maximal in vivo blood concentration over the half-maximal in in vitro activity concentration), will give a useful approximation for concentrations where in vivo interactions are likely. Further, for doses where maternal blood concentrations are likely to elicit an interaction (Cmax/AC50>0.1), where do the compounds accumulate in fetal tissues? In order to estimate these doses based on Tox21 data, in silico parameters of chemical fraction unbound in plasma and intrinsic hepatic clearance were estimated from ADMET predictor (Simulations-Plus Inc.) and used in the HTTK R-package to obtain Cmax values from a physiologically-based toxicokinetics model. In silico estimated Cmax values predicted in vivo human Cmax with median absolute error of 0.81 for 93 chemicals, giving confidence in the R-package and in silico estimates. A case example evaluating Cmax/AC50 values for peroxisome proliferator-activated receptor gamma (PPARγ) and glucocorticoid receptor revealed known compounds (glitazones and corticosteroids, respectively) highest on the list at pharmacological doses. Doses required to elicit likely interactions across all Tox21/ToxCast assays were compared to estimated daily exposures (Wambaugh et. al., 2014). 199 compounds were estimated to have likely interactions across 1-32 assays for the most conservative 95th % population at doses lower than estimated daily environmental exposures. The major chemical use-categories included pharmaceuticals, chemical intermediates and dyes. Maximum fetal tissue accumulation (2nd trimester-birth) ranged from the most to least accumulated tissue: rest of body, gut, kidney, lung, brain, and thyroid. 3,3′,5,5′-Tetrabromobisphenol A and Triphenyltin acetate were among the top affecters across tissues (excluding thyroid) at concentrations disrupting nuclear receptors (PPARγ and retinoid X receptor, respectively). This approach can prioritize compounds and biological pathways quickly when no experimental data exists. Out of domain compounds, passive transport, and later developmental stage are present and need to be evaluated. This approach has shown promise toward estimating in vivo interaction concentrations for HTS data. This abstract does not reflect official NTP or EPA views.

Computational and Organotypic Modeling of Microcephaly (Teratology Society)

Microcephaly is associated with reduced cortical surface area and ventricular dilations. Many genetic and environmental factors precipitate this malformation, including prenatal alcohol exposure and maternal Zika infection. This complexity motivates the engineering of computational and experimental models to probe the underlying molecular targets, cellular consequences, and biological processes. We describe an Adverse Outcome Pathway (AOP) framework for microcephaly derived from literature on all gene-, chemical-, or viral- effects and brain development. Overlap with NTDs is likely, although the AOP connections identified here focused on microcephaly as the adverse outcome. A query of the Mammalian Phenotype Browser database for ‘microcephaly’ (MP:0000433) returned 85 gene associations; several function in microtubule assembly and centrosome cycle regulated by (microcephalin, MCPH1), a gene for primary microcephaly in humans. The developing ventricular zone is the likely target. In this zone, neuroprogenitor cells (NPCs) self-replicate during the 1st trimester setting brain size, followed by neural differentiation of the neocortex. Recent studies with human NPCs confirmed infectivity with Zika virions invoking critical cell loss (apoptosis) of precursor NPCs; similar findings have been shown with fetal alcohol or methylmercury exposure in rodent studies, leading to mathematical models of NPC dynamics in size determination of the ventricular zone. A key event in this determination is the plane of mitotic divisions oriented by the centriole. NPCs divide symmetrically before switching to asymmetric (neurogenic) divisions by early 2nd trimester, and a premature switching (or excessive apoptosis) results in a critical reduction in precursor population NPC pool size at the onset of neurogenesis. The putative AOP has broad applicability to the pathogenesis of microcephaly induced by genetic or environmental factors. Search of EPA’s ToxRefDB database returned 75 chemicals with relevant, nonsystemic developmental effects on brain development: 40 (51%) invoke reductions in brain size or cellular mass, 39 (52%) invoke dilated ventricles or hydrocephaly, and only 5 (6.3%) invoke both defects. Brain mimicks developed from hNPCs + iPSC-derived endothelia and microglia provide experimental models that can be used to test the key events and their relationships in the proposed AOP for microcephaly in a human system. [This abstract does not reflect US EPA policy].

Watching the Aurora From Orbit

Expedition 52 Flight Engineer Jack Fischer of NASA shared photos and time-lapse video of a glowing green aurora seen from his vantage point 250 miles up, aboard the International Space Station. This aurora photo was taken on June 26, 2017.

Drinking Water Microbiome as a Screening Tool for Nitrification in Chloraminated Drinking Water Distribution Systems

Many water utilities in the US using chloramine as disinfectant treatment in their distribution
systems have experienced nitrification episodes, which detrimentally impact the water quality. A
chloraminated drinking water distribution system (DWDS) simulator was operated through four
successive operational schemes, including two stable events (SS) and an episode of nitrification
(SF), followed by a ‘chlorine burn’ (SR) by switching disinfectant from chloramine to free
chlorine. The current research investigated the viability of biological signatures as potential
indicators of operational failure and predictors of nitrification in DWDS. For this purpose, we
examined the bulk water (BW) bacterial microbiome of a chloraminated DWDS simulator
operated through successive operational schemes, including an episode of nitrification. BW data
was chosen because sampling of BW in a DWDS by water utility operators is relatively simpler
and easier than collecting biofilm samples from underground pipes. The methodology applied a
supervised classification machine learning approach (naïve Bayes algorithm) for developing
predictive models for nitrification. Classification models were trained with biological datasets
(Operational Taxonomic Unit [OTU] and genus-level taxonomic groups) generated using next
generation high-throughput technology, and divided into two groups (i.e. binary) of positives and
negatives (Failure and Stable, respectively). We also investigated biomass and water quality
signatures as potential predictors of nitrification in DWDS and evaluated the signatures identified
in this study as potential predictors of nitrification in publically available data.

Passive Gas-Gap Heat Switches for Use in Low-Temperature Cryogenic Systems

Abstract: We present the current state of development in passive gas-gap heat switches. This type of switch does not require a separate heater to activate heat transfer but, instead, relies upon the warming of one end due to an intrinsic step in a thermodynamic cycle to raise a getter above a threshold temperature. Above this temperature sequestered gas is released to couple both sides of the switch. This enhances the thermodynamic efficiency of the system and reduces the complexity of the control syst…

Performance Evaluation of the International Space Station Flow Boiling and Condensation Experiment (FBCE) Test Facility

Abstract: A ground-based experimental facility to perform flow boiling and condensation experiments is built in support of the development of the long duration Flow Boiling and Condensation Experiment (FBCE) destined for operation on board of the International Space Station (ISS) Fluid Integrated Rack (FIR). We performed tests with the condensation test module oriented horizontally and vertically. Using FC-72 as the test fluid and water as the cooling fluid, we evaluated the operational characteristics…