Robotic telescopes in education

The power of robotic telescopes to transform science education has been voiced by multiple sources, since the 1980s. Since then, much technical progress has been made in robotic telescope provision to end users via a variety of different approaches. The educational transformation hoped for by the provision of this technology has, so far, yet to be achieved on a scale matching the technical advancements. In this paper, the history, definition, role and rationale of optical robotic telescopes with a focus on their use in education is provided. The current telescope access providers and educational projects and their broad uses in traditional schooling, undergraduate and outreach are then outlined. From this background, the current challenges to the field, which are numerous, are then presented. This review is concluded with a series of recommendations for current and future projects that are apparent and have emerged from the literature

Measuring dry plant residues in grasslands: A case study using AVIRIS

Grasslands, savannah, and hardwood rangelands are critical ecosystems and sensitive to disturbance. Approximately 20 percent of the Earth's surface are grasslands and represent 3 million ha. in California alone. Developing a methodology for estimating disturbance and the effects of cumulative impacts on grasslands and rangelands is needed to effectively monitor these ecosystems. Estimating the dry biomass residue remaining on rangelands at the end of the growing season provides a basis for evaluating the effectiveness of land management practices. The residual biomass is indicative of the grazing pressure and provides a measure of the system capacity for nutrient cycling since it represents the maximum organic matter available for decomposition, and finally, provides a measure of the erosion potential for the ecosystem. Remote sensing presents a possible method for measuring dry residue. However, current satellites have had limited application due to the coarse spatial scales (relative to the patch dynamics) and insensitivity of the spectral coverage to resolve dry plant material. Several hypotheses for measuring the biochemical constituents of dry plant material, particularly cellulose and lignin, using high spectral resolution sensors were proposed. The use of Airborne Visible/Infrared Imaging Spectrometers (AVIRIS) to measure dry plant residues over an oak savannah on the eastern slopes of the Coast Range in central California was investigated and it was asked what spatial and spectral resolutions are needed to quantitatively measure dry plant biomass in this ecosystem

Longitudinal Monitoring of SARS-CoV-2 IgM and IgG Seropositivity to Detect COVID-19.

BackgroundSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a novel beta-coronavirus that has recently emerged as the cause of the 2019 coronavirus pandemic (COVID-19). Polymerase chain reaction (PCR) based tests are optimal and recommended for the diagnosis of an acute SARS-CoV-2 infection. Serology tests for viral antibodies provide an important tool to diagnose previous exposure to the virus. Here we evaluate the analytical performance parameters of the Diazyme SARS-CoV-2 IgM/IgG serology assays and describe the kinetics of IgM and IgG seroconversion observed in patients with PCR-confirmed COVID-19 who were admitted to our hospital.MethodsWe validated the performance of the Diazyme assay in 235 presumed SARS-CoV-2 negative subjects to determine specificity. Subsequently, we evaluated the SARS-CoV-2 IgM and IgG seroconversion of 54 PCR-confirmed COVID-19 patients and determined sensitivity of the assay at three different timeframes.ResultSensitivity and specificity for detecting seropositivity at ≥15 days following a positive SARS-CoV-2 PCR result, was 100.0% and 98.7% when assaying for the panel of IgM and IgG. The median time to seropositivity observed for a reactive IgM and IgG result from the date of a positive PCR was 5 days (IQR: 2.75-9 days) and 4 days (IQR: 2.75-6.75 days), respectively.ConclusionsOur data demonstrate that the Diazyme IgM/IgG assays are suited for the purpose of detecting SARS-CoV-2 IgG and IgM in patients with suspected SARS-CoV-2 infections. For the first time, we report longitudinal data showing the evolution of seroconversion for both IgG and IgM in a cohort of acutely ill patients in the United States. We also demonstrate a low false positive rate in patients who were presumed to be disease free

136 HIV-1 Nef regulates activity of endoplasmic reticulum chaperone calnexin

HIV-1 Nef promotes viral replication by downmodulating a number of cell surface transmembrane proteins, such as CD4, MHC-I and MHC-II, which are targeted by Nef to various degradation pathways. Nef is also responsible for downregulation of cellular cholesterol transporter ABCA1, and this effect contributes to development of atherosclerosis in HIV infected patients. Surprisingly, in contrast to CD4 and MHC I, to which Nef has to bind to exert downregulation, binding to ABCA1 turned out to be unnecessary for inactivation of ABCA1 by Nef. Here, we identified a novel mechanism by which Nef influences activity of host cell and viral proteins. We show that Nef interacts with an endoplasmic reticulum chaperone calnexin, which is essential for folding and maturation of glycosylated proteins. Nef disrupts calnexin interaction with ABCA1, thus impairing functionality of this protein, but increases affinity and enhances interaction of calnexin with gp160, promoting maturation and functionality of viral Env proteins. Knock-down of calnexin lead to reduced fusion activity of HIV-1 envelope and reduced virion infectivity, as well as to defective cholesterol efflux, which is mediated by ABCA1. However, gp160 and ABCA1 interacted with calnexin differently: while gp160 binding to calnexin was dependent on glycosylation, interaction of ABCA1 with calnexin was glycosylation-independent. Therefore, Nef binds to calnexin and stimulates interaction between calnexin and gp160 at the expense of ABCA1 and probably other ER proteins. These results provide a mechanistic explanation for previously unexplained effect of Nef on functionality of ABCA1, and suggest a mechanism for upregulation of HIV infectivity by Nef through stimulation of Env maturation

Liquid chromatography high-resolution TOF analysis: investigation of MSE for broad-spectrum drug screening.

BackgroundHigh-resolution mass spectrometry (HRMS) has the potential to supplement other drug screening platforms used in toxicology laboratories. HRMS offers high analytical specificity, which can be further enhanced by incorporating a fragment ion for each analyte. The ability to obtain precursor ions and fragment ions using elevated collision energies (MS(E)) can help improve the specificity of HRMS methods.MethodsWe developed a broad-spectrum screening method on an ultraperformance liquid chromatography TOF mass spectrometer (UPLC-TOF-MS) using the MS(E) mode. A diverse set of patient samples were subjected to a simple dilute, hydrolyze, and shoot protocol and analyzed in a blind manner. Data were processed with 3 sets of criteria with increasing stringency, and the results were compared with the reference laboratory results.ResultsA combination of retention time match (±0.2 min), a protonated analyte, and fragment ion mass accuracy of ±5 ppm produced zero false-positive results. Using these criteria, we confirmed 92% (253/275) of true positives. The positive confirmation rate increased to 98% (270/275) when the requirement for a fragment ion was dropped, but also produced 53 false positives. A total of 136 additional positive drug findings not identified by the reference methods were identified with the UPLC-TOF-MS.ConclusionsMS(E) provides a unique way to incorporate fragment ion information without the need of precursor ion selection. A primary limitation of requiring a fragment ion for positive identification was that certain drug classes required high-energy collisions, which formed many fragment ions of low abundance that were not readily detected

Speckle Space-Time Covariance in High-Contrast Imaging

We introduce a new framework for point-spread function (PSF) subtraction based on the spatio-temporal variation of speckle noise in high-contrast imaging data where the sampling timescale is faster than the speckle evolution timescale. One way that space-time covariance arises in the pupil is as atmospheric layers translate across the telescope aperture and create small, time-varying perturbations in the phase of the incoming wavefront. The propagation of this field to the focal plane preserves some of that space-time covariance. To utilize this covariance, our new approach uses a Karhunen-Lo\'eve transform on an image sequence, as opposed to a set of single reference images as in previous applications of Karhunen-Lo\'eve Image Processing (KLIP) for high-contrast imaging. With the recent development of photon-counting detectors, such as microwave kinetic inductance detectors (MKIDs), this technique now has the potential to improve contrast when used as a post-processing step. Preliminary testing on simulated data shows this technique can improve contrast by at least 10-20% from the original image, with significant potential for further improvement. For certain choices of parameters, this algorithm may provide larger contrast gains than spatial-only KLIP.Comment: Accepted to A