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The operations of the New England Research Application Center's IBM 1130 are described and the problems of using it for chemical information retrieval are discussed. (Author/JB)

An advanced and newly developed severe plastic deformation (SPD) method called accumulative fold-forging (AFF) was applied to produce layered nanostructured MgNi alloys exhibiting superior hydrogen storage capacity. Microstructural developments and storage properties were characterized in depth to correlate the structure and performance of this advanced material. The enhanced hydrogen storage performance of the magnesium-based layered composite material was investigated in comparison to the pristine state by conducting hydrogenation and dehydrogenation testing. It was also shown that the hydrogen uptake and release characteristics can be controlled by adjusting the layered structure or the Mg: Ni stoichiometry ratio. Refining the grain structure of the magnesium alloy down to the nano-scale range (∼400–900 nm) by applying high cycles AFF consolidation to promote creation of multi-million nanometric interfaces led to superior storage performance with a remarkable hydrogen absorption capacity of up to ∼1.425 wt%. X-ray diffraction (XRD) analysis of the hydrogenated products revealed the formation of MgH2 that indicates the dominance of the magnesium matrix for controlling the hydrogen storage behavior of the layered Mg/Ni composite material. Finally, the relationship between the directional hydrogen storage behavior and the induced structural features upon AFF treatment were also established using quantitative characterization and analytical tools.

The production of polyacrylonitrile (PAN)-based carbon fiber includes two major steps, stabilization (oxidization) and carbonization. Stabilization is a slow and energy-consuming process and involves using a series of ovens that need to be carefully tuned to achieve desirable quality at the lowest cost. This usually involves meeting fiber density or cyclization levels at each zone of the oxidation furnace, often achieved through trial and error by a team of skilled operators. In this work, a simple empirical model was developed to predict density from oven system parameters and cyclization onset temperature of the PAN feedstock, parametrized as Sn, representing the oxidation depth. The relative cyclization index (RCI) and density of the fibers were analyzed after various oxidation treatments and were used to derive the model parameters. The RCI of stabilized fiber was well represented by a logistic function incorporating Sn while the fiber density was well predicted by a polynomial function of RCI. The model was verified using stabilization trials conducted on the same precursor in a continuous oven system and in a batch oven, and then on a second commercial precursor using the batch oven. Statistical analysis on these trials shows good agreement with model predictions.

Selective cyclooxygenase (COX)-2 inhibitors have been extensively studied for colorectal cancer (CRC) chemoprevention. Celecoxib has been reported to reduce the incidence of colorectal adenomas and CRC but is also associated with an increased risk of cardiovascular events. Here, we report a series of gut-restricted, selective COX-2 inhibitors characterized by high colonic exposure and minimized systemic exposure. By establishing acute ex vivo 18F-FDG uptake attenuation as an efficacy proxy, we identified a subset of analogues that demonstrated statistically significant in vivo dose-dependent inhibition of adenoma progression and survival extension in an APCmin/+ mouse model. However, in vitro-in vivo correlation analysis showed their chemoprotective effects were driven by residual systemic COX-2 inhibition, rationalizing their less than expected efficacies and highlighting the challenges associated with COX-2-mediated CRC disease chemoprevention.

To tackle the COVID-19 outbreak, which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there is an unmet need for highly accurate diagnostic tests at all stages of infection with rapid results and high specificity. Here, we present a label-free nanoplasmonic biosensor-based, multiplex screening test for COVID-19 that can quantitatively detect 10 different biomarkers (6 viral nucleic acid genes, 2 spike protein subunits, and 2 antibodies) with a limit of detection in the aM range, all within one biosensor platform. Our newly developed nanoplasmonic biosensors demonstrate high specificity, which is of the upmost importance to avoid false responses. As a proof of concept, we show that our detection approach has the potential to quantify both IgG and IgM antibodies directly from COVID-19-positive patient plasma samples in a single instrument run, demonstrating the high-throughput capability of our detection approach. Most importantly, our assay provides receiving operating characteristics, areas under the curve of 0.997 and 0.999 for IgG and IgM, respectively. The calculated p-value determined through the Mann–Whitney nonparametric test is 96% (77/80), a positive predictive value of 98% at 5% prevalence, and a negative predictive value of 100% at 5% prevalence. We believe that our very sensitive, multiplex, high-throughput testing approach has potential applications in COVID-19 diagnostics, particularly in determining virus progression and infection severity for clinicians for an appropriate treatment, and will also prove to be a very effective diagnostic test when applied to diseases beyond the COVID-19 pandemic.

Recent decades have witnessed an increasing number of studies investigating petroleum systems with the application of rhenium-osmium (Re-Os) isotopic geochemistry. Here, we review the use of the 187Re-187Os geochronometer with respect to the geochemical behaviour of rhenium and osmium in hydrocarbon-related geological processes. The Re-Os budget in hydrocarbon source rock predominantly originates from natural water columns during its deposition. Open seawater tends to have a homogeneous Os isotopic composition because its residence time in seawater is longer than the time taken for ocean mixing. On the contrary, restricted water bodies (e.g., lakes) may have heterogeneous Os isotopic compositions due to the greater amount of terrigenous input. Hydrogenous Re and Os atoms are sequestered from the water body into sedimentary organic matter and transferred into crude oil through thermal maturation of organic matter. Thermal maturation likely does not significantly alter the Re-Os isotopic systematics of the source rock as a Re-Os isochron age of 442±21 Ma (2σ) is yielded in this study for over matured source rocks within the Silurian Longmaxi Formation from the Sichuan Basin. Re-Os atoms are mainly hosted by the highly polar/aggregating/aromatic asphaltenes in hydrocarbons, possibly chelating with organic complexes or occurring as metalloporphyrins. Resin and aromatic hydrocarbons also contribute to the Re-Os budget, but are 2 to 3 orders of magnitude lower than that of asphaltenes, whereas saturates do not contain appreciable Re-Os contents. The distribution of Re-Os atoms in hydrocarbons is heterogeneous because the duplicate analysis of pure single bitumen samples yields similar 187Os/188Os ratios whereas variable 187Re/188Os ratios. The Re-Os system in crude oils can be reset during transport away from the source rocks, with Os-rich organic fractions more readily expelled than Re-rich fractions. Contact with metal-rich fluids (e.g., hydrothermal fluid) or compositional changes related to asphaltene contents (e.g., deasphalting, biodegradation, thermal cracking and thermochemical sulphate reduction) are also likely to alter the Re-Os systematics in hydrocarbons. These geochemical features enable the 187Re-187Os isotopic system to have robust applicability for petroleum system investigations, which may use the Re-Os radiometric tool for: (1) stratigraphic correlation of source rocks, (2) dating geological events altering the asphaltene content in hydrocarbon such as hydrocarbon generation, thermochemical sulphate reduction, etc., and, (3) fingerprinting hydrocarbons. Regardless of the robustness of the 187Re-187Os geochronometer for petroleum system investigations, there are several pending questions such as partitioning between solid organic species or between organic matter and sulphide, chelating sites in hydrocarbons and Os isotopic equilibration between hydrocarbon subfractions. To improve the understanding of the Re-Os behaviour in petroleum systems, we underscore multi-proxies-based geochemistry (e.g., inorganic-organic geochemistry) and experimental studies (e.g., hydrous pyrolysis).

The aim of the experiment was to check the effectiveness of the varroacide veterinary product called PolyVar Yellow® (flumethrin 275 mg) in field conditions in the area of north-eastern Poland. The experiment was carried out on twenty bee colonies, of which in ten (group PY) were tested with the veterinary product and the remaining ten constituted a control group without anti-varroosis treatment (group C). Treatment began in mid-August and lasted until the end of October when bee flights ceased. A control treatment was then conducted with a 3.2% oxalic acid solution. The effectiveness of Varroacide of PolyVar Yellow® was estimated on the basis of the parasite falls on the Varroa sticky inserts and based on the infestation rate of bees with the parasite before and after the treatment. High varroacide effectiveness of the preparation was obtained at 97%. The tested veterinary product was shown to protect effectively bee colonies against reinvasion of Varroa destructor mites.

The most frequently detected substances prohibited by the World Anti-Doping Agency (WADA) belong to the anabolic steroids class. The most challenging compounds among this class are the endogenous anabolic steroids, which are detected by quantitative measurement of testosterone (T) and its metabolites with a so-called "steroid profiling" method. The current steroid profile is based on the concentrations and ratios of the sum of free and glucuronidated steroids. Recently, our group developed a steroid profiling method for the detection of three free steroids and 14 intact steroid conjugates, including both the glucuronic acid conjugated and sulfated fraction. The study aimed at evaluating the long-term stability of steroid conjugate concentrations and ratios, and the influence of different endogenous steroids on this extended steroid profile. A single dose of oral T undecanoate (TU), topical T gel, topical dihydrotestosterone (DHT) gel, and oral dehydroepiandrosterone (DHEA) was administered to six healthy male volunteers. One additional volunteer with a homozygote deletion of the UGT2B17 gene (del/del genotype) received a single topical dose of T gel. An intramuscular dose of TU was administered to another volunteer. To avoid fluctuation of steroid concentrations caused by variations in urinary flow rates, steroid ratios were calculated and evaluated as possible biomarkers for the detection of endogenous steroid abuse with low doses. Overall, sulfates do not have substantial additional value in prolonging detection times for the investigated endogenous steroids and administration doses. The already monitored glucuronides were overall the best markers and were sufficient to detect the administered steroids.

During cytokinesis, the actin cytoskeleton is partitioned into two spatially distinct actin isoform specific networks: a β-actin network that generates the equatorial contractile ring, and a γ-actin network that localizes to the cell cortex. Here we demonstrate that the opposing regulation of the β- and γ-actin networks is required for successful cytokinesis. While activation of the formin DIAPH3 at the cytokinetic furrow underlies β-actin filament production, we show that the γ-actin network is specifically depleted at the cell poles through the localized deactivation of the formin DIAPH1. During anaphase, CLIP170 is delivered by astral microtubules and displaces IQGAP1 from DIAPH1, leading to formin autoinhibition, a decrease in cortical stiffness and localized membrane blebbing. The contemporaneous production of a β-actin contractile ring at the cell equator and loss of γ-actin from the poles is required to generate a stable cytokinetic furrow and for the completion of cell division., During cell division, the actin cytoskeletal network at both the equatorial contractile ring and cell cortex are known to play a role, but the regulation of γ-actin during cytokinesis is less well understood. Here, the authors show that recruitment of β-actin to the contractile ring and loss of γ-actin from the cell poles is required for completion of cell division.

Tropospheric ozone (O3) negatively impacts human health and is also a greenhouse gas. It is formed photochemically by reactions of nitrogen oxides (NOx) and volatile organic compounds (VOCs), of which wildfires are an important source. This study presents data from research flights sampling wildfires in West and Central African savannah regions, both close to the fires and after the emissions had been transported several days over the tropical North Atlantic Ocean. Emission factors (EFs) in g kg−1 for NOx (as NO), six VOCs and formaldehyde were calculated from enhancement to mole fractions in data taken close to the fires. For NOx, the emission factor was calculated as 2.05 ± 0.43 g kg−1 for Senegal and 1.20 ± 0.28 g kg−1 for Uganda, both higher than the average value of 1.13 ± 0.6 g kg−1 for previous studies of African savannah regions. For most VOCs (except acetylene), EFs in Uganda were lower by factors of 20–50% compared to Senegal, with almost all the values below those in the literature. O3 enhancement in the fire plumes was investigated by examining the ΔO3/ΔCO enhancement ratio, with values ranging from 0.07–0.14 close to the fires up to 0.25 for measurements taken over the Atlantic Ocean up to 200 hours downwind. In addition, measurements of O3 and its precursors were compared to the output of a global chemistry transport model (GEOS-CF) for the flights over the Atlantic Ocean. Normalised mean bias (NMB) comparison between the measured and modelled data was good outside of the fire plumes, with CO showing a model under-prediction of 4.6% and O3 a slight over-prediction of 0.7% (both within the standard deviation of the data). For NOx the agreement was poorer, with an under-prediction of 9.9% across all flights. Inside the fire plumes the agreement between modelled and measured values is worse, with the model being biased significantly lower for all three species. In total across all flights, there was an under-prediction of 29.4%, 16.5% and 37.5% for CO, O3 and NOx respectively. Finally, the measured ΔO3/ΔCO enhancement ratios were compared to those in the model for the equivalent flight data, with the model showing a lower value of 0.17 ± 0.03 compared to an observed value of 0.29 ± 0.05. The results detailed here show that the O3 burden to the North Atlantic Ocean from African wildfires may be underestimated and that further study is required to better study the O3 precursor emissions and chemistry.

Cu-based catalysts have shown structural instability during the electrochemical CO2 reduction reaction (CO2RR). However, studies on monometallic Cu catalysts do not allow a nuanced differentiation between the contribution of the applied potential and the local concentration of CO as the reaction intermediate since both are inevitably linked. We first use bimetallic Ag-core/porous Cu-shell nanoparticles, which utilise nanoconfinement to generate high local CO concentrations at the Ag core at potentials at which the Cu shell is still inactive for the CO2RR. Using operando liquid cell TEM in combination with ex situ TEM, we can unequivocally confirm that the local CO concentration is the main source for the Cu instability. The local CO concentration is then modulated by replacing the Ag-core with a Pd-core which further confirms the role of high local CO concentrations. Product quantification during CO2RR reveals an inherent trade-off between stability, selectivity and activity in both systems., The stability of bimetallic AgCu and PdCu catalysts for electrochemical CO2RR is investigated using the combination of operando and ex situ TEM. The local CO concentration is identified as the main link between activity, stability and selectivity.

We report changes in surface nitrogen dioxide ( NO2 ) across the UK during the COVID-19 pandemic when large and rapid emission reductions accompanied a nationwide lockdown (23 March–31 May 2020, inclusively), and compare them with values from an equivalent period over the previous 5 years. Data are from the Automatic Urban and Rural Network (AURN), which forms the basis of checking nationwide compliance with ambient air quality directives. We calculate that NO2 reduced by 42 %±9.8 % on average across all 126 urban AURN sites, with a slightly larger ( 48 %±9.5 % ) reduction at sites close to the roadside (urban traffic). We also find that ozone ( O3 ) increased by 11 % on average across the urban background network during the lockdown period. Total oxidant levels ( O x = NO 2 + O 3 ) increased only slightly on average ( 3.2 %±0.2 % ), suggesting the majority of this change can be attributed to photochemical repartitioning due to the reduction in NOx . Generally, we find larger, positive Ox changes in southern UK cities, which we attribute to increased UV radiation and temperature in 2020 compared to previous years. The net effect of the NO2 and O3 changes is a sharp decrease in exceedances of the NO2 air quality objective limit for the UK, with only one exceedance in London in 2020 up until the end of May. Concurrent increases in O3 exceedances in London emphasize the potential for O3 to become an air pollutant of concern as NOx emissions are reduced in the next 10–20 years.

Nano-electrochemical tools to assess individual catalyst entities are critical to comprehend single-entity measurements. The intrinsic electrocatalytic activity of an individual well-defined Co3 O4 nanoparticle supported on a carbon-based nanoelectrode is determined by employing an efficient SEM-controlled robotic technique for picking and placing a single catalyst particle onto a modified carbon nanoelectrode surface. The stable nanoassembly is microscopically investigated and subsequently electrochemically characterized. The hexagonal-shaped Co3 O4 nanoparticles demonstrate size-dependent electrochemical activity and exhibit very high catalytic activity with a current density of up to 11.5 A cm-2 at 1.92 V (vs. RHE), and a turnover frequency of 532±100 s-1 at 1.92 V (vs. RHE) towards catalyzing the oxygen evolution reaction.

In vitro genotoxicity studies are a quick and high throughput approach to assess the genotoxic potential of chemicals; however, the reliability of these tests and their relevance to in vivo effects depends on the choice of representative cell line and optimisation of assay conditions. For chemicals like urethane that require specific metabolic activation to cause genotoxicity, it is important that in vitro tests are conducted using cell lines exhibiting the activity and induction of CYP450 enzymes, including CYP2E1 enzyme that is important in the metabolism of urethane, at a concentration representing actual or perceived chemical exposure. We compared 2D MCL-5 cells and HepG2 cells with 3D HepG2 hanging drop spheroids to determine the genotoxicity of urethane using the micronucleus assay. Our 2D studies with MCL-5 did not show any statistically significant genotoxicity [99% relative population doubling (RPD)] compared to controls for concentrations and time point tested in vitro. HepG2 cells grown as 2D indicated that exposure to urethane of up to 30 mM for 23 h did not cause any genotoxic effect (102% RPD) but, at higher concentrations, genotoxicity was produced with only 89–85% RPD. Furthermore, an exposure of 20–50 mM for 23 h using 3D hanging drop spheroid assays revealed a higher MN frequency, thus exhibiting in vitro genotoxicity of urethane in metabolically active cell models. In comparison with previous studies, this study indicated that urethane genotoxicity is dose, sensitivity of cell model (2D vs. 3D) and exposure dependent.

Tracer diffusion of the matrix elements in CoCrFeNiMn-based high-entropy alloys with 0.2, 0.5 and 0.8 at.% carbon is measured at 1373 K. The diffusion coefficients are found to depend non-monotonously on the carbon content. The diffusion retardation in low-C alloys is discussed in terms of the impact of interstitially-dissolved carbon on the vacancy concentration and the migration barriers in the alloy. In high-C alloys, formation of carbides alternates the observed trends, most probably by increasing the total vacancy concentration.

The cross section for the combined 2D(15N,p)16N and 2D(15N,nγ)16O nuclear reactions of deuterium (2D) with incident 15N ions is evaluated and found to increase by two orders of magnitude between 3.3 and 7.0 MeV. Detecting the γ-rays at 6.1 and 7.1 MeV from these reactions allows quantifying the depth-integrated 2D content in materials in parallel with nanometer-resolved quantitative hydrogen (1H) depth profiling in surface layers through resonant 1H(15N,αγ)12C nuclear reaction analysis (NRA) using 15N ion beams. The information depth and sensitivity of 15N-2D NRA is estimated through energy loss simulations of the 15N projectiles in the analyzed material. Good agreement of the integral 2D quantitation through 2D(15N,p)16N and 2D(15N,nγ)16O NRA with 2D depth profiles obtained independently via 2D(3He,p)4He NRA is demonstrated at the example of 2D plasma-exposed tungsten samples. The simultaneous quantitation of 2D and depth-resolved 1H profiling with a single 15N ion beam promises application potential to investigate hydrogen-isotope exchange and diffusion processes in surface and thin buried layers.

Variable-resolution fluctuation electron microscopy (VR-FEM) data from measurements on amorphous silicon and PdNiP have been obtained at varying experimental conditions. Measurements have been conducted at identical total electron dose and with an identical electron dose normalized to the respective probe size. STEM probes of different sizes have been created by variation of the semi-convergence angle or by defocus. The results show that defocus yields a reduced normalized variance compared to data from probes created by convergence angle variation. Moreover, the trend of the normalized variance upon probe size variation differs between the two methods. Beam coherence, which affects FEM data, has been analyzed theoretically using geometrical optics on a multi-lens setup and linked to the illumination conditions. Fits to several experimental beam profiles support our geometrical optics theory regarding probe coherence. The normalized variance can be further optimized if one determines the optimal exposure time for the nanobeam diffraction patterns.

Key steps in the functionalization of an unactivated arene often involve its dihaptocoordination by a transition metal followed by insertion into the C-H bond. However, rarely are the η2-arene and aryl hydride species in measurable equilibrium. In this study, the benzene/phenyl hydride equilibrium is explored for the {WTp(NO)(PBu3)} (Bu = n-butyl; Tp = trispyrazoylborate) system as a function of temperature, solvent, ancillary ligand, and arene substituent. Both face-flip and ring-walk isomerizations are identified through spin-saturation exchange measurements, which both appear to operate through scission of a C-H bond. The effect of either an electron-donating or electron-withdrawing substituent is to increase the stability of both arene and aryl hydride isomers. Crystal structures, electrochemical measurements, and extensive NMR data further support these findings. Static density functional theory calculations of the benzene-to-phenyl hydride landscape suggest a single linear sequence for this transformation involving a sigma complex and oxidative cleavage transition state. Static DFT calculations also identified an η2-coordinated benzene complex in which the arene is held more loosely than in the ground state, primarily through dispersion forces. Although a single reaction pathway was identified by static calculations, quasiclassical direct dynamics simulations identified a network of several reaction pathways connecting the η2-benzene and phenyl hydride isomers, due to the relatively flat energy landscape.

Spurred by better understanding of disease biology, improvements in molecular diagnostics, and the development of targeted therapies, the treatment of acute myeloid leukemia (AML) has undergone significant evolution in recent years. Arguably, the most exciting shift has come from the success of treatment with the B-cell lymphoma-2 inhibitor venetoclax. When given in combination with a hypomethylating agent or low dose cytarabine, venetoclax demonstrates high response rates, some of which are durable. In spite of this, relapses after venetoclax treatment are common, and much interest exists in elucidating the mechanisms of resistance to the drug. Alterations in leukemic stem cell metabolism have been identified as a possible escape route, and clinical trials focusing on targeting metabolism in AML are ongoing. This review article highlights current research regarding venetoclax treatment and resistance in AML with a focus on cellular metabolism.

This paper reports the epitaxial growth of EuH2 thin films with an ω-scan full width at half-maximum of 0.07°, the smallest value for metal hydride thin films reported so far. The thin films were d...

We quantified nutrient concentrations and water quality parameters in soils and water from a working farm (in operation for over 100 years), through contrasting agricultural wetlands, to their receiving waters. Contrasting wetlands were a forested alluvial swamp and a ditched wetland swale. Our objective was to determine if nutrients diminished in concentration or changed in form as water moved through wetlands below the farm. Soils were collected from around the farm and receiving wetlands and were analyzed for nitrate, ammonium, and phosphorus. Water samples, collected from shallow piezometers and surface waters were analyzed for nitrate + nitrite, and total phosphorus. Nitrate in groundwater and surface water in the alluvial swamp were much lower than concentrations measured in flows from farmlands. Nitrogen in upland water was dominated by nitrate, but ammonium dominated in the swamp. Phosphorus was low in wetland soils and also diminished through the swamp. Despite receiving agricultural run-off for many decades, the natural alluvial swamp still provided an effective environment for water quality mitigation of nitrate and phosphorus. The ditched wetland swale did not significantly reduce nitrate but appeared to provide some phosphorus mitigation. Agricultural wetland conservation is an especially effective, low cost tool for water quality management.

Gastric emptying refers to a process in which the stomach discharges its contents into the small intestine to further digest and absorb nutrients. Understanding the mechanisms of gastric emptying and relationships between food and individuals is of paramount importance for the design and manufacture of novel and healthy foods. For ethical and cost reasons, in vivo tests are not always possible. In vitro digestion models therefore play a key role in current exploration of gastric emptying. This review outlines the mechanisms and physiology of gastric emptying, including calories, viscosity, composition of the food, age and gender of the individual. In addition, recent progress on in vitro static and dynamic gastric digestion models and future research trends are included in this review.

The exceptionally π-basic metal fragments {MoTp-(NO)(DMAP)} and {WTp(NO)(PMe(3))} (Tp = tris(pyrazolyl)borate; DMAP = 4-(N,N-dimethylamino)pyridine) form thermally stable η(2)-coordinated complexes with a variety of electron-deficient arenes. The tolerance of substituted arenes with fluorine-containing electron withdrawing groups (EWG; −F, −CF(3), −SF(5)) is examined for both the molybdenum and tungsten systems. When the EWG contains a π bond (nitriles, aldehydes, ketones, ester), η(2) coordination occurs predominantly on the nonaromatic functional group. However, complexation of the tungsten complex with trimethyl orthobenzoate (PhC(OMe)(3)) followed by hydrolysis allows access to an η(2)-coordinated arene with an ester substituent. In general, the tungsten system tolerates sulfur-based withdrawing groups well (e.g., PhSO(2)Ph, MeSO(2)Ph), and the integration of multiple electron-withdrawing groups on a benzene ring further enhances the π-back-bonding interaction between the metal and aromatic ligand. While the molybdenum system did not form stable η(2)-arene complexes with the sulfones or ortho esters, it was capable of forming rare examples of stable η(2)-coordinated arene complexes with a range of fluorinated benzenes (e.g., fluorobenzene, difluorobenzenes). In contrast to what has been observed for the tungsten system, these complexes formed without interference of C–H or C–F insertion.

Background: Idiopathic epiretinal membranes (ERM) are common with potential for severe visual loss. Surgical outcomes are excellent but predominantly reported from healthy eye studies rather than those with co-morbidities. We report a series of patients with subretinal drusenoid deposits (SRDD) and comorbid ERM with post-operative complications or poor outcomes, describing potential pitfalls to avoid. Case Presentation: This is a case series illustrating the poor functional and morphological outcomes following ERM surgery in five eyes with SRDD. These eyes appear at risk of geographic atrophy (GA), choroidal neovascular membrane (CNVM) formation (pre-and post-operatively) and outer retinal atrophy (ORA), all of which can limit outcomes. Conclusion: ERM surgery in eyes with SRDD presents specific challenges. Assessment of outer retinal changes can be challenging pre-operatively, particularly with significant oedema. Identification of patients with SRDD in ERM eyes often relies on examination of the contralateral eye. Appropriate listing is paramount, with care taken to rule out pre-existing GA or CNVM through use of fundus fluorescein angiography. Patients should be given a guarded prognosis during the consenting process if the outer retina is poorly visualized.

Dihapto-coordinate 1,2-dihydropyridine complexes of the metal fragment {WTp(NO)(PMe(3))} (Tp = tris(pyrazolyl)borate), derived from pyridine, are demonstrated to undergo protonation at C6 followed by regioselective amination at C5 with a variety of primary and secondary amines. The addition takes place stereoselectively anti to the metal center, producing exclusively cis-disubstituted products. The resulting 1,2,5,6-tetrahydropyridines can be successfully liberated by oxidation, providing a route to novel molecules of potential medicinal interest.

Stewartia is a genus of flowering shrubs and trees in the family Theaceae. Stewartia species are native to eastern Asia, with the exception of S. ovata and S. malacodendron, which are indigenous to southeastern North America. Despite having outstanding ornamental value and unique horticultural features, Stewartias are not readily available for landscaping in the horticultural trade due to difficulty with mass propagation. In addition to commercial propagation, there is a need to develop propagation techniques for the conservation of the North American species, which are rare (S. ovata) or endangered (S. malacodendron). This research examined somatic embryogenesis as a means to mass propagate Asian and North American Stewartia species and to provide material for cryopreservation of valuable Stewartia germplasm. By testing a variety of plant growth regulators (PGRs), somatic embryogenesis was induced from immature zygotic embryo explants of seven Stewartia species—five Asian and two North American. Additionally, embryogenic cultures were obtained from three North American cultivars, S. malacodendron ‘Delmarva’, S. ovata ‘Red Rose’, and ‘Royal Purple’. For two Stewartia species, S. ovata and S. sinensis, somatic embryogenesis was induced from immature endosperm. Picloram (0.05 or 0.1 mg/L) and 2,4-dichlorophenoxyacetic (2 or 4 mg/L) were the most effective PGRs for inducing somatic embryogenesis of North American and Asian Stewartia species, respectively. All seven Stewartia species examined produced somatic embryos that converted into plants that could be transferred to the greenhouse. Embryogenic tissue from five Stewartia species were successfully put into cryo-storage and recovered, providing a means of long-term germplasm storage. This is the first report of somatic embryogenesis in the genus Stewartia. This is the first report of somatic embryogenesis from immature zygotic embryos in the genus Stewartia and it was accomplished with seven different species.

One of the leading causes of failure for any bone implant is implant-associated infections. The implant-bone interface is in fact the crucial site of infection where both the microorganisms and cells compete to populate the newly introduced implant surface. Most of the work dealing with this issue has focused on the design of implant coatings capable of preventing infection while ignoring cell proliferation or vice versa. The present study is therefore focused on investigating the antibacterial and biological properties of nanocomposite coatings based on an amorphous hydrocarbon (a-C:H) matrix containing silver nanoparticles (AgNPs). a-C:H coatings with varying silver concentrations were generated directly on medical grade titanium substrates using a combination of a gas aggregation source (GAS) and a plasma-enhanced chemical vapor deposition (PE-CVD) process. The obtained results revealed that the surface silver content increased from 1.3 at % to 5.3 at % by increasing the used DC magnetron current in the GAS from 200 to 500 mA. The in vitro antibacterial assays revealed that the nanocomposites with the highest number of silver content exhibited excellent antibacterial activities resulting in a 6-log reduction of Escherichia coli and a 4-log reduction of Staphylococcus aureus after 24 h of incubation. An MTT assay, fluorescence live/dead staining, and SEM microscopy observations of MC3T3 cells seeded on the uncoated and coated Ti substrates also showed that increasing the amount of AgNPs in the nanocomposites had no notable impact on their cytocompatibility, while improved cell proliferation was especially observed for the nanocomposites possessing a low amount of AgNPs. These controllable Ag/a-C:H nanocomposites on Ti substrates, which simultaneously provide an excellent antibacterial performance and good biocompatibility, could thus have promising applications in orthopedics and other biomedical implants.