High-resolution Instruments Research Articles

The binary system of the spinning-top Be star Achernar

Context.Achernar, the closest and brightest classical Be star, presents rotational flattening, gravity darkening, occasional emission lines due to a gaseous disk, and an extended polar wind. It is also a member of a close binary system with an early A-type dwarf companion.Aims.We aim to determine the orbital parameters of the Achernar system and to estimate the physical properties of the components.Methods.We monitored the relative position of Achernar B using a broad range of high angular resolution instruments of the VLT/VLTI (VISIR, NACO, SPHERE, AMBER, PIONIER, GRAVITY, and MATISSE) over a period of 13 years (2006−2019). These astrometric observations are complemented with a series of ≈750 optical spectra for the period from 2003 to 2016.Results.We determine that Achernar B orbits the primary Be star on a seven-year period, eccentric orbit (e = 0.7258 ± 0.0015) which brings the two stars within 2 au at periastron. The mass of the Be star is found to bemA = 6.0 ± 0.6 M⊙for a secondary mass ofmB = 2.0 ± 0.1 M⊙(the latter was estimated from modeling). We find a good agreement of the parameters of Achernar A with the evolutionary model of a critically rotating star of 6.4 M⊙at an age of 63 Ma. The equatorial plane of the Be star and the orbital plane of the companion exhibit a relative inclination of 30°. We also identify a resolved comoving low-mass star, which leads us to propose that Achernar is a member of the Tucana-Horologium moving group.Conclusions.The proximity of Achernar makes this star a precious benchmark for stellar evolution models of fast rotators and intermediate mass binaries. Achernar A is presently in a short-lived phase of its evolution following the turn-off, during which its geometrical flattening ratio is the most extreme. Considering the orbital parameters, no significant interaction occurred between the two components, demonstrating that Be stars may form through a direct, single-star evolution path without mass transfer. Since component A will enter the instability strip in a few hundred thousand years, Achernar appears to be a promising progenitor of the Cepheid binary systems.

Increased levels of cell wall degrading enzymes and peptidases are associated with aggressiveness in a virulent isolate of Pyrenophora teres f. maculata

Pyrenophora teres f. maculata (Ptm) is a fungal pathogen that causes the spot form of net blotch on barley and leads to economic losses in many of the world's barley-growing regions. Isolates of Ptm exhibit varying levels of aggressiveness that result in quantifiable changes in the severity of the disease. Previous research on plant-pathogen interactions has shown that such divergence is reflected in the proteome and secretome of the pathogen, with certain classes of proteins more prominent in aggressive isolates. Here we have made a detailed comparative analysis of the secretomes of two Ptm isolates, GPS79 and E35 (highly and mildly aggressive, respectively) using a proteomics-based approach. The secretomes were obtained in vitro using media amended with barley leaf sections. Secreted proteins therein were harvested, digested with trypsin, and fractionated offline by HPLC prior to LC-MS in a high-resolution instrument to obtain deep coverage of the proteome. The subsequent analysis used a label-free quantitative proteomics approach with relative quantification of proteins based on precursor ion intensities. A total of 1175 proteins were identified, 931 from Ptm and 244 from barley. Further analysis revealed 160 differentially abundant proteins with at least a two-fold abundance difference between the isolates, with the most enriched in the aggressive GPS79 secretome. These proteins were mainly cell-wall (carbohydrate) degrading enzymes and peptidases, with some oxidoreductases and other pathogenesis-related proteins also identified, suggesting that aggressiveness is associated with an improved ability of GPS79 to overcome cell wall barriers and neutralize host defense responses.

Fan-shaped jet close to a light bridge

Aims. On the Sun, jets in light bridges (LBs) are frequently observed with high-resolution instruments. The respective roles played by convection and the magnetic field in triggering such jets are not yet clear. Methods. We report a small fan-shaped jet along a LB observed by the 1.6m Goode Solar Telescope (GST) with the TiO Broadband Filter Imager (BFI), the Visible Imaging Spectrometer (VIS) in Hα, and the Near-InfraRed Imaging Spectropolarimeter (NIRIS), along with the Stokes parameters. The high spatial and temporal resolution of those instruments allowed us to analyze the features identified during the jet event. By constructing the Hα Dopplergrams, we found that the plasma is first moving upward, whereas during the second phase of the jet, the plasma is flowing back. Working with time slice diagrams, we investigated the propagation-projected speed of the fan and its bright base. Results. The fan-shaped jet developed within a few minutes, with diverging beams. At its base, a bright point was slipping along the LB and ultimately invaded the umbra of the sunspot. The Hα profiles of the bright points enhanced the intensity in the wings, similarly to the case of Ellerman bombs. Co-temporally, the extreme ultraviolet (EUV) brightenings developed at the front of the dark material jet and moved at the same speed as the fan, leading us to propose that the fan-shaped jet material compressed and heated the ambient plasma at its extremities in the corona. Conclusions. Our multi-wavelength analysis indicates that the fan-shaped jet could result from magnetic reconnection across the highly diverging field low in the chromosphere, leading to an apparent slipping motion of the jet material along the LB. However, we did not find any opposite magnetic polarity at the jet base, as would typically be expected in such a configuration. We therefore discuss other plausible physical mechanisms, based on waves and convection, that may have triggered the event.

Gravitational lensing effects of supermassive black holes in cluster environments

ABSTRACT This study explores the gravitational lensing effects of supermassive black holes (SMBHs) in galaxy clusters. While the presence of central SMBHs in galaxies is firmly established, recent work from high-resolution simulations predict the existence of an additional population of wandering SMBHs. Though the masses of these SMBHs are a minor perturbation on the larger scale and individual galaxy scale dark matter components in the cluster, they can impact statistical lensing properties and individual lensed image configurations. Probing for these potentially observable signatures, we find that SMBHs imprint detectable signatures in rare, higher order strong lensing image configurations although they do not manifest any statistically significant detectable evidence in either the magnification distribution or the integrated shear profile. Investigating specific lensed image geometries, we report that a massive, near point-like, potential of an SMBH causes the following detectable effects: (i) image splitting leading to the generation of extra images; (ii) positional and magnification asymmetries in multiply imaged systems; and (iii) the apparent disappearance of a lensed counter image. Of these, image splitting inside the cluster tangential critical curve, is the most prevalent notable observational signature. We demonstrate these possibilities in two cases of observed giant arcs in SGAS J003341.5+024217 and RX J1347.5−1145, wherein specific image configurations seen can be reproduced with SMBHs. Future observations with high-resolution instrumentation (e.g. MAVIS-Very Large Telescope, MICADO-Extremely Large Telescope, and the upgraded ngVLA, along with data from the Euclid and Nancy Grace Roman Space Telescopes and the Rubin LSST Observatory are likely to allow us to probe these unique yet rare SMBHs lensing signatures.

Prediction of Retention Time and Collision Cross Section (CCSH+, CCSH-, and CCSNa+) of Emerging Contaminants Using Multiple Adaptive Regression Splines.

Ultra-high performance liquid chromatography coupled to ion mobility separation and high-resolution mass spectrometry instruments have proven very valuable for screening of emerging contaminants in the aquatic environment. However, when applying suspect or nontarget approaches (i.e., when no reference standards are available), there is no information on retention time (RT) and collision cross-section (CCS) values to facilitate identification. In silico prediction tools of RT and CCS can therefore be of great utility to decrease the number of candidates to investigate. In this work, Multiple Adaptive Regression Splines (MARS) were evaluated for the prediction of both RT and CCS. MARS prediction models were developed and validated using a database of 477 protonated molecules, 169 deprotonated molecules, and 249 sodium adducts. Multivariate and univariate models were evaluated showing a better fit for univariate models to the experimental data. The RT model (R2 = 0.855) showed a deviation between predicted and experimental data of ±2.32 min (95% confidence intervals). The deviation observed for CCS data of protonated molecules using the CCSH model (R2 = 0.966) was ±4.05% with 95% confidence intervals. The CCSH model was also tested for the prediction of deprotonated molecules, resulting in deviations below ±5.86% for the 95% of the cases. Finally, a third model was developed for sodium adducts (CCSNa, R2 = 0.954) with deviation below ±5.25% for 95% of the cases. The developed models have been incorporated in an open-access and user-friendly online platform which represents a great advantage for third-party research laboratories for predicting both RT and CCS data.

Quantitating α-amidated peptide degradation by separative technologies and ultra-high resolution mass spectrometry

α-amidation of peptides is a C-terminal modification allowing to improve half-life of therapeutic peptides. However, due to storage conditions, this C-terminal amide function can be partially hydrolyzed into a carboxylic acid moiety, resulting in a decrease of the molecule bioactivity. It is therefore necessary to be able to detect and quantify any trace of this degradation product when dealing with such class of peptides. For this purpose, LC-UV, CE-UV, LC/MS and LC/MS/MS are conventional analytical technologies used in pharmaceutical laboratories to monitor peptide integrity. Since the production of the carboxylated peptide issued from the amidated starting compound is scrutinized, ultra-high-resolution mass spectrometry was investigated without the recourse to any separative method (direct infusion mode) to achieve rapid straightforward relative quantitative analyses from the detected isotopic clusters of both peptides. Indeed, low or high-resolution MS instruments present in pharmaceutical laboratories (fitted with Q, IT or ToF mass analyzers) allow to distinguish both molecular ions that differ from 0.984 Da (NH2 formally substituted by OH). However, the analytical difficulty comes from the fact that the A+1 ion (13C contribution) of the amidated peptide and the A ion (12C contribution) of any produced carboxylated sequence are overlapping hampering the detection of minute amount of the hydrolyzed product. Actually, to differentiate these two isobaric ions, mass analyzers should possess at least a resolution of 90 000 for 7 residues peptides (molecular ions around 700–800 Da) which is presumably attainable with any FT-MS instrument. With an ultra-high-resolution mass spectrometer (FT-ICR MS) the observed fine isotopic structure displaying all expected isotopologues permitted in a single fast analysis to unambiguously detect both compounds (non-hydrolyzed and hydrolyzed one) and subsequently define the relative amount of the carboxylated peptide contaminant. Finally, these results were confronted with conventional measurements recorded with orthogonal methodologies such as LC-UV and CE-UV. The pro and cons of all quantitative strategies are discussed.

Design and Experiment of High-Resolution Multispectral Polarization Imaging System

This paper addresses the objectives in a complex context: the polarization mathematical and physical model of the basic components of the target/background is constructed by simulation modeling. The image fusion experiment is carried out based on a two-dimensional wavelet transformation. A high-resolution polarization imaging instrument was developed, and static experiments were carried out with polarization, infrared, and visible cameras. The result shows that using polarization imaging detection technology to detect physical evidence targets in complex backgrounds can effectively improve target contrast. It can enrich the target information, improve image quality, and improve target detection accuracy.

Relationship between Joint Roughness Coefficient and Statistical Roughness Parameters and Its Sensitivity to Sampling Interval

Accurate determination of the surface roughness is of significant importance in estimating the mechanical and hydraulic behaviors of rock joints. The correlation between joint roughness coefficient (JRC) and various statistical roughness parameters calculated from digitized Barton’s roughness profiles was explored with Pearson’s correlation coefficient method. The results show the strongest correlation between the standard deviation of the roughness angle and JRC following an excellent linear relationship. In addition, the correlation in the JRC with textural parameters is better than its correlation with amplitude parameters. Twenty-nine rock joint surfaces from fine sandstone, coarse sandstone and granite joint samples with a wide range of surface morphology were digitized using a high-resolution 3D scanner instrument. Further, the statistical roughness parameter values were calculated for each joint profile at eight different sampling intervals for sensitivity analysis of these statistical roughness parameters with regard to the sampling interval. The result indicated that textural parameters generally have a certain degree of dependency on sampling interval, following a power-law relationship. Specifically, when the sampling interval increases, the structure function value increases whereas it decreases for other textural parameters. In contrast, the dependence of the amplitude parameters on the sampling interval is not significant.

A New Perspective on Magnetotail Electron and Ion Divergent Flows: MMS Observations.

Fast divergent flows of electrons and ions in the magnetotail plasma sheet are conventionally interpreted as a key reconnection signature caused by the magnetic topology change at the X-line. Therefore, reversals of the x-component (V x⊥) of the plasma flow perpendicular to the magnetic field must correlate with the sign changes in the north-south component of the magnetic field (B z ). Here we present observations of the flow reversals that take place with no correlated B z reversals. We report six such events, which were measured with the high-resolution plasma and fields instruments of the Magnetospheric Multiscale mission. We found that electron flow reversals in the absence of B z reversals (a) have amplitudes of ∼1,000-2,000kms-1 and durations of a few seconds; (b) are embedded into larger-scale ion flow reversals with enhanced ion agyrotropy; and (c) compared with conventional reconnection outflows around the electron diffusion regions (EDRs), have less (if ever) pronounced electron agyrotropy, dawnward electron flow amplitude, and electric field strength toward the neutral sheet, although their energy conversion parameters, including the Joule heating rate, are quite substantial. These results suggest that such flow reversals develop in the ion-demagnetization regions away from electron-scale current sheets, in particular the EDRs, and yet they play an important role in the energy conversion. These divergent flows are interpreted as precursors of the flow-driven reconnection onsets provided by the ion tearing or the ballooning/interchange instability.

Analysis of lignins using 31P benchtop NMR spectroscopy: quantitative assessment of substructures and comparison to high-field NMR

Lignin is quickly emerging as a biomass-derived source for the production of some crucial organic chemistry building blocks, typically obtained from unsustainable and non-renewable petroleum feedstocks. As a complex polymer, lignin characterization is often challenging due to its random structure and multitudes of different repeating substructures. Over the last 20 years, advances in our understanding and processing of lignin, as well as important work on its characterization using 31P NMR, have led to numerous publications highlighting the many potential uses of this material. With the emergence of high-resolution benchtop NMR instruments, these types of analyses can now be accessed by many laboratories and industries that have historically not been able to take advantage of NMR due to cost or size constraints. Herein, we demonstrate that benchtop NMR is a viable technique for the 31P NMR analysis of lignin and compare our results to those obtained on a traditional high-field instrument.

Utility of an alternative method (to USEPA Method 1613) for analysis of priority persistent organic pollutants in soil from mixed industrial-suburban areas of Durban, South Africa.

This study evaluates the adequacy of a USEPA Method 1613 alternative analytical method for analysis of persistent organic pollutants (POPs) in soil from the immediate vicinity of industrialized areas in the eThekwini municipal area in South Africa. The objective of this study is in line with the Stockholm Convention Article 11 on research, development, and monitoring. Furthermore, it became imperative to find an alternative analytical procedure to USEPA Method 1613 that could cater to studies conducted in Africa where recent reviews have indicated that most African countries lack the technical and instrumental capacity for performing analysis of dioxin-like compounds according to USEPA Method 1613, which entails the use of high-resolution chromatography and high-resolution mass spectrometry instrumentation. The study aimed to ascertain the utility of an alternative two-dimensional gas chromatography-time of flight mass spectrometry method for analysis of trace-level priority POPs in soil, along with a fast single quadrupole gas chromatography-mass spectrometry method. The analytical methods were applied to the analysis of POPs on soil samples from industrial areas with oil refineries and a pulp and paper manufacturing company, while other samples were collected near the electricity substations and a landfill site. Analytical results showed BDE 209 as the dominant contaminating polybrominated diphenyl ether (concentration ranges from 0.006 to 5.71 ng g-1 ). Polybrominated biphenyls (PBBs) 9, 10, and 49 were the dominant PBBs detected in 78% of the sites tested, although their concentrations were below the limit of quantification (LOQ). Polychlorinated dibenzo-p-dioxins and furans and dioxin-like polychlorinated biphenyls detected could not be quantified above their respective LOQs, indicating that the Durban area has low priority pollutant contamination levels compared to other regions around the world. The methods developed are a starting point thatwill inform considerations for routine evaluation and management of soil contamination, which plays a vital role in environmental management. IntegrEnviron Assess Manag 2023;19:749-762. © 2022 SETAC.

Specific analysis of highly absorbing nanoporous powder by small-angle X-ray scattering.

The characterization of nanoporous powders of highly absorbing compounds by small-angle X-ray scattering (SAXS) involves overcoming several difficulties before quantitative information related to the porous texture, such as the specific surface and the porous volume, can be derived. In this article, first, the contribution of the grain facet reflectivity and scattering from the bulk of a grain with the density of ThO2, a highly absorbing material, were calculated. Microporous ThO2 powder having micrometric grain size was characterized, in which the scattering signal is predominant. A high-resolution synchrotron instrument was used in order to cover a wider q range and minimize the absorption effect, and the results were compared with those obtained using a laboratory X-ray source. Concerning the absorption problem existing with a laboratory X-ray source, a new and robust experimental method was proposed to correctly determine the scattering intensity of the highly absorbing granular samples on an absolute scale. This method allows one to calculate accurately the porous volume and the specific surface via Porod's law and the invariant using a laboratory SAXS instrument. This last result opens new perspectives for the characterization of the volume and the specific surface of highly absorbing actinide oxide powders.

Advancing Cyclic Ion Mobility Mass Spectrometry Methods for Studying Biomolecules: Toward the Conformational Dynamics of Mega Dalton Protein Aggregates.

Native mass spectrometry is a powerful tool for the analysis of noncovalent complexes. When coupled with high-resolution ion mobility, this technique can be used to investigate the conformational changes induced in said complexes by different solution or gas-phase conditions. In this study, we describe how a new-generation high-resolution ion mobility instrument equipped with a cyclic ion mobility cell can be utilized for the analysis of large biomolecular systems, including temperature-induced protein aggregates of masses greater than 1.5 MDa, as well as a 63 kDa oligonucleotide complex. The effects of and the interplay between the voltages applied to the different components of the cyclic ion mobility spectrometry system on ion transmission and arrival time distribution were demonstrated using biomolecules covering the m/z range 2000-10,000. These data were used to establish a theoretical framework for achieving the best separation in the cyclic ion mobility system. Finally, the cyclic ion mobility mass spectrometer was coupled with a temperature-controlled electrospray ionization source to investigate high-mass protein aggregation. This analysis showed that it was possible to continuously monitor the change in abundance for several conformations of MDa aggregates with increasing temperature. This work significantly increases the range of biomolecules that can be analyzed by both cyclic ion mobility and temperature-controlled electrospray ionization mass spectrometry, providing new possibilities for high-resolution ion mobility analysis.

Experimental study of mitochondrion-targeted small molecule IR-61 ameliorated exhaustive exercise-induced cardiac injury in rats

To investigate the effects of mitochondrion-targeted cyanine fluorescent small molecule IR-61 on cardiac injury induced by exhaustive exercise in rats. Thirty-six adult male SD rats were randomly divided into 3 groups(n=12),control group (Ctrl), exhaustive exercise group (EE) and IR-61+ exhaustive exercise group (IR-61+EE). IR-61+EE group were intraperitoneally injected with 2 mg/kg IR-61 at the same time on day 1, 4 and 7. One hour after the end of the last drug administration, the two exhaustive exercise groups were subjected to exhaustive exercise modeling. The rats were placed on an animal treadmill with a slope of 0° at a speed of 10~15 m/min to coordinate their limbs running posture, and then ran at a speed of 25~30 m/min until exhaustion about 15 minutes later. After the animal models established, ECG was recorded by physiological recorder, myocardial injury was observed by light microscope, mitochondrial injury was observed by transmission electron microscope, myocardial cell apoptosis was detected by TUNEL method, markers of myocardial injury were detected by ELISA, and myocardial mitochondrial respiration rate was measured by high-resolution Oxygraph-2K mitochondrial instrument. ① Compared with Ctrl group, heart rate was increased, PR interval was shortened, QRS interval was prolonged, QTc was prolonged and ST segment was depressed significantly in EE group (P＜0.05). In EE group, myocardial fiber fracture and mitochondrial inner chamber swelling were obvious, mitochondrial crest was fuzzy, mitochondrial outer membrane was incomplete, and a large number of mitochondrial rupture and fusion were visible. In EE group, TUNEL staining cells were abundant, chromatin concentration and marginalization, nuclear membrane lysis, chromatin fragmentation into massive apoptotic bodies, apoptosis score increased (P＜0.05). The levels of creatine kinase isoenzyme-MB (CK-MB), cardiac troponin I(cTn-I) and N-terminal B-type natriuretic peptide (NT-proBNP) were increased in EE group (P＜0.05). Basal respiration rate, oxidative respiration rate of fatty acids and respiration rate of complex Ⅰ, Ⅱ and Ⅳ were all decreased (P＜ 0.05). ② Compared with EE group, the heart rate in IR-61+EE group was increased, PR interval was prolonged, QRS interval was shortened, QTc was shortened, ST segment was not significantly depressed (P＜0.05). In IR-61+EE group, myocardial fiber arrangement was loose, no obvious fracture was observed, mitochondrial inner ventricle was swelling, mitochondrial outer membrane was intact, TUNEL stained cells and unstained cells were observed, the overall morphology was more similar to Ctrl group. Apoptosis index was decreased (P＜0.05), the levels of CK-MB and cTn-I were decreased in IR-61+EE group (P＜0.05). The oxidative respiration rate of fatty acids and the respiration rate of complex Ⅱ and Ⅳ were increased (P＜0.05). Mitochondrion-targeted cyanine fluorescent small molecule IR-61 can improve cardiac electrical activity, reduce myocardial cell injury and mitochondrial injury, reduce myocardial cell apoptosis, and improve the myocardial mitochondrial energy metabolism condition in exhausted rats.

A MEMS modulator-based dual-channel mid-infrared laser heterodyne radiometer for simultaneous remote sensing of atmospheric CH4, H2O and N2O.

The performance of a micro-electro-mechanical system (MEMS) modulator-based dual-channel mid-infrared laser heterodyne radiometer (MIR-LHR) was demonstrated in ground-based solar occultation mode for the first time. A MEMS mirror was employed as an alternative modulator to the traditional mechanical chopper, which makes the system more stable and compact. Two inter-band cascade lasers (ICL) centered at 3.53 µm and 3.93 µm, were employed as local oscillators (LO) to probe absorption lines of methane (CH4), water vapor (H2O) and nitrous oxide (N2O). The system stability greater than 1000 s was evaluated by Allan variance. The experimental MIR-LHR spectra (acquired at Hefei, China, on February 24th 2022) of two channels were compared and were in good agreement with simulation spectra from atmospheric transmission modeling. The mixing ratio of CH4, H2O and N2O were determined to be ∼1.906 ppm, 3069 ppm and ∼338 ppb, respectively. The reported MEMS modulator-based dual-channel MIR-LHR in this manuscript has great potential to be a portable and high spectral resolution instrument for remote sensing of multi-component gases in the atmospheric column.

Spatial Proteomics Reveals Differences in the Cellular Architecture of Antibody-Producing CHO and Plasma Cell–Derived Cells

Most of the recombinant biotherapeutics employed today to combat severe illnesses, for example, various types of cancer or autoimmune diseases, are produced by Chinese hamster ovary (CHO) cells. To meet the growing demand of these pharmaceuticals, CHO cells are under constant development in order to enhance their stability and productivity. The last decades saw a shift from empirical cell line optimization toward rational cell engineering using a growing number of large omics datasets to alter cell physiology on various levels. Especially proteomics workflows reached new levels in proteome coverage and data quality because of advances in high-resolution mass spectrometry instrumentation. One type of workflow concentrates on spatial proteomics by usage of subcellular fractionation of organelles with subsequent shotgun mass spectrometry proteomics and machine learning algorithms to determine the subcellular localization of large portions of the cellular proteome at a certain time point. Here, we present the first subcellular spatial proteome of a CHO-K1 cell line producing high titers of recombinant antibody in comparison to the spatial proteome of an antibody-producing plasma cell–derived myeloma cell line. Both cell lines show colocalization of immunoglobulin G chains with chaperones and proteins associated in protein glycosylation within the endoplasmic reticulum compartment. However, we report differences in the localization of proteins associated to vesicle-mediated transport, transcription, and translation, which may affect antibody production in both cell lines. Furthermore, pairing subcellular localization data with protein expression data revealed elevated protein masses for organelles in the secretory pathway in plasma cell–derived MPC-11 (Merwin plasma cell tumor-11) cells. Our study highlights the potential of subcellular spatial proteomics combined with protein expression as potent workflow to identify characteristics of highly efficient recombinant protein–expressing cell lines. Data are available via ProteomeXchange with identifier PXD029115.

Design considerations for a cycloidal mass analyzer using a focal plane array detector.

With the advent of technologies such as ion array detectors and high energy permanent magnet materials, there is renewed interest in the unique focusing properties of the cycloidal mass analyzer and its ability to enable small, high-resolution, and high-sensitivity instruments. However, most literature dealing with the design of cycloidal mass analyzers assumes a single channel detector because at the time of those publications, compatible multichannel detectors were not available. This manuscript introduces and discusses considerations and a procedure for designing cycloidal mass analyzers coupled with focal plane ion array detectors. To arrive at a set of relevant design considerations, we first review the unique focusing properties of the cycloidal mass analyzer and then present calculations detailing how the dimensions and position of the focal plane array detector relative to the ion source determine the possible mass ranges and resolutions of a cycloidal mass analyzer. We present derivations and calculations used to determine the volume of homogeneous electric and magnetic fields needed to contain the ion trajectories and explore the relationship between electric and magnetic field homogeneity on resolving power using finite element analysis (FEA) simulations. A set of equations relating the electric field homogeneity to the geometry of the electric sector electrodes was developed by fitting homogeneity values from 78 different FEA models. Finally, a sequence of steps is suggested for designing a cycloidal mass analyzer employing an array detector.

Impact of Established and Emerging Software Tools on the Metabolite Identification Landscape.

Scientists’ ability to detect drug-related metabolites at trace concentrations has improved over recent decades. High-resolution instruments enable collection of large amounts of raw experimental data. In fact, the quantity of data produced has become a challenge due to effort required to convert raw data into useful insights. Various cheminformatics tools have been developed to address these metabolite identification challenges. This article describes the current state of these tools. They can be split into two categories: Pre-experimental metabolite generation and post-experimental data analysis. The former can be subdivided into rule-based, machine learning-based, and docking-based approaches. Post-experimental tools help scientists automatically perform chromatographic deconvolution of LC/MS data and identify metabolites. They can use pre-experimental predictions to improve metabolite identification, but they are not limited to these predictions: unexpected metabolites can also be discovered through fractional mass filtering. In addition to a review of available software tools, we present a description of pre-experimental and post-experimental metabolite structure generation using MetaSense. These software tools improve upon manual techniques, increasing scientist productivity and enabling efficient handling of large datasets. However, the trend of increasingly large datasets and highly data-driven workflows requires a more sophisticated informatics transition in metabolite identification labs. Experimental work has traditionally been separated from the information technology tools that handle our data. We argue that these IT tools can help scientists draw connections via data visualizations and preserve and share results via searchable centralized databases. In addition, data marshalling and homogenization techniques enable future data mining and machine learning.

Small-scale solar jet formation and their associated waves and instabilities

Studies on small-scale jets’ formation, propagation, evolution, and role, such as type I and II spicules, mottles, and fibrils in the lower solar atmosphere’s energetic balance, have progressed tremendously thanks to the combination of detailed observations and sophisticated mathematical modelling. This review provides a survey of the current understanding of jets, their formation in the solar lower atmosphere, and their evolution from observational, numerical, and theoretical perspectives. First, we review some results to describe the jet properties, acquired numerically, analytically and through high-spatial and temporal resolution observations. Further on, we discuss the role of hydrodynamic and magnetohydrodynamic instabilities, namely Rayleigh–Taylor and Kelvin–Helmholtz instabilities, in jet evolution and their role in the energy transport through the solar atmosphere in fully and partially ionised plasmas. Finally, we discuss several mechanisms of magnetohydrodynamic wave generation, propagation, and energy transport in the context of small-scale solar jets in detail. This review identifies several gaps in the understanding of small-scale solar jets and some misalignments between the observational studies and knowledge acquired through theoretical studies and numerical modelling. It is to be expected that these gaps will be closed with the advent of high-resolution observational instruments, such as Daniel K. Inouye Solar Telescope, Solar Orbiter, Parker Solar Probe, and Solar CubeSats for Linked Imaging Spectropolarimetry, combined with further theoretical and computational developments.

Internal wave breaking near the foot of a steep East-Pacific continental slope

The sloping sides of ocean basins are of particular interest for their potential importance for considerable turbulence generation via internal wave breaking and associated water circulation. The difference with the ocean interior may be manifest in a 10–100 m relatively thin layer above the seafloor. We set up an observational study with high-resolution stand-alone instrumentation attached to a custom-made release-anchor frame sampling to within 0.5 m from the seafloor up to 150 m above it. For two months, the taut wire moored instrumentation was tested in 1100 m water depth of the East-Pacific, off the coast of San Diego (CA, USA). The mooring was oceanward of an underwater bank and near the foot of its steep but gentle two-dimensional slope. Temperature sensor data demonstrate that internal waves peak at semidiurnal frequencies. While short (<1 h) periods show complicated structure, tidally averaged turbulence dissipation rate monotonically increases towards the seafloor over two orders of magnitude. The largest turbulence dissipation rates are observed during the relatively warm phase of an internal wave. Although the local topographic slope is supercritical for semidiurnal internal waves, turbulent bores propagating up the slope and hydraulic jumps are not observed. Most of the turbulence appears to be dominated by shear production, but not related to steady frictional flow near the seafloor.