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On-going shrinkage of Greenland's icecap, permafrost thaw, and changes in precipitation are exposing its landscapes to erosion and remobilization of ancient organic carbon (OC) held in soils and sedimentary rocks. The fate of this OC and potential feedbacks to climate are still unclear. Here, we show that the glacial Zackenberg river (Northeastern Greenland) exports aged particulate OC (POC, uncalibrated radiocarbon ages of ∼4,000 years). Many of the smaller periglacial streams affected by abrupt permafrost thaw transport substantially older POC (up to 32,000 years), especially with enhanced discharge following intense precipitation. Mineralogical analysis, and density and size fractionation of soils and both glacial and nonglacial river sediments reveal that OC is largely associated with phyllosilicate minerals, suggesting stabilization against microbial processing. Enhanced export of ancient, mineral-associated OC as a consequence of summer rainfall may accelerate translocation of OC from terrestrial to marine environments, but could have limited consequences for climate., Geophysical Research Letters, 49 (21), ISSN:0094-8276, ISSN:1944-8007

A new version of the Australian Community Climate and Earth System Simulator coupled model, ACCESS-CM2, has been developed for a wide range of climate modelling research and applications. In particular, ACCESS-CM2 is one of Australia’s contributions to the World Climate Research Programme’s Coupled Model Intercomparison Project Phase 6 (CMIP6). Compared with the ACCESS1.3 model used for our CMIP5 submission, all model components have been upgraded as well as the coupling framework (OASIS3-MCT) and experiment control system (Rose/Cylc). The component models are: UM10.6 GA7.1 for the atmosphere, CABLE2.5 for the land surface, MOM5 for the ocean, and CICE5.1.2 for the sea ice. This paper describes the model configuration of ACCESS-CM2, documents the experimental set up, and assesses the model performance for the preindustrial spin-up simulation in comparison against (reconstructed) observations and ACCESS1.3 results. While the performance of the two generations of the ACCESS coupled model is largely comparable, ACCESS-CM2 shows better global hydrological balance, more realistic ocean water properties (in terms of spatial distribution) and meridional overturning circulation in the Southern Ocean but a poorer simulation of the Antarctic sea ice and a larger energy imbalance at the top of atmosphere. This energy imbalance reflects a noticeable warming trend of the global ocean over the spin-up period.

Integration of a rear surface nanophotonic grating can increase photocurrent in ultra-thin solar cells. Transparent gratings formed of dielectric materials and high bandgap semiconductors can offer efficient diffraction with lower parasitic absorption than more widely studied metal/dielectric equivalents. In these systems, the maximum photocurrent which can be obtained for a grating made of a given combination of materials is shown to follow a simple empirical model based on the optical constants of these materials and independent of grating dimensions. The grating dimensions still require optimization in order to maximize the photocurrent for a given active layer thickness by balancing the effects of diffraction outside the front surface escape cone and the tuning of waveguide modes in long wavelength regions which are poorly absorbed in an ultra-thin film. The optimal grating pitch is shown to be of particular relevance for both effects, changing nonmonotonically as the absorber gets thicker in order to track favourable waveguide mode resonances at wavelengths near the absorber bandgap. These trends together with the empirical model for material selection drastically reduce the design space for highly efficient light trapping with transparent gratings.

Blood–brain barrier (BBB) dysfunction is a key hallmark in the pathology of many neuroinflammatory disorders. Extracellular vesicles (EVs) are lipid membrane-enclosed carriers of molecular cargo that are involved in cell-to-cell communication. Circulating endothelial EVs are increased in the plasma of patients with neurological disorders, and immune cell-derived EVs are known to modulate cerebrovascular functions. However, little is known about whether brain endothelial cell (BEC)-derived EVs themselves contribute to BBB dysfunction. Human cerebral microvascular cells (hCMEC/D3) were treated with TNFα and IFNy, and the EVs were isolated and characterised. The effect of EVs on BBB transendothelial resistance (TEER) and leukocyte adhesion in hCMEC/D3 cells was measured by electric substrate cell-substrate impedance sensing and the flow-based T-cell adhesion assay. EV-induced molecular changes in recipient hCMEC/D3 cells were analysed by RT-qPCR and Western blotting. A stimulation of naïve hCMEC/D3 cells with small EVs (sEVs) reduced the TEER and increased the shear-resistant T-cell adhesion. The levels of microRNA-155, VCAM1 and ICAM1 were increased in sEV-treated hCMEC/D3 cells. Blocking the expression of VCAM1, but not of ICAM1, prevented sEV-mediated T-cell adhesion to brain endothelia. These results suggest that sEVs derived from inflamed BECs promote cerebrovascular dysfunction. These findings may provide new insights into the mechanisms involving neuroinflammatory disorders.

Clinical isolates of influenza virus produce pleiomorphic virions, ranging from small spheres to elongated filaments. The filaments are seemingly adaptive in natural infections, but their basic functional properties are poorly understood and functional studies of filaments often report contradictory results. This may be due to artefactual damage from routine laboratory handling, an issue which has been noted several times without being explored in detail. To determine whether standard laboratory techniques could damage filaments, we used immunofluorescence microscopy to rapidly and reproducibly quantify and characterise the dimensions of filaments. Most of the techniques we tested had minimal impact on filaments, but freezing to -70°C, a standard storage step before carrying out functional studies on influenza viruses, severely reduced their concentration, median length and the infectivity of the whole virion population. We noted that damage from freezing is likely to have affected most of the functional studies of filaments performed to date, and to address this we show that it can be mitigated by snap-freezing or incorporating the cryoprotectant DMSO. We recommend that functional studies of filaments characterise virion populations prior to analysis to ensure reproducibility, and that they use unfrozen samples if possible and cryoprotectants if not. These basic measures will support the robust functional characterisations of filaments that are required to understand their roles in natural influenza virus infections.

Ultra-thin (less than 100 nm thick) photovoltaics are proposed as an enabling technology for space power applications due to their intrinsic radiation tolerance. Outside of the Earth's atmosphere, spacecraft are bombarded with energetic electrons and protons which can cause dislocations in the lattice structure of their solar cell materials thus limiting mission lifetimes. Certain orbits that could be advantageous for imaging, security and network coverage of the Earth are currently inaccessible due to high levels of radiation making them inhospitable to space craft. Ultra-thin cells have superior radiation tolerance but lower optical absorption which necessitates the integration of a nanophotonic light-trapping structure. The first iteration of ultra-thin 80 nm absorber layer devices patterned by Displacement Talbot Lithography has shown promising electrical and optical performance.

The introduction of light scattering structures for efficient absorption of incident illumination is essential in ultra-thin solar cells given their reduced optical path length. The growing interest in these devices demands attaining high efficiencies through the identification of optimal designs to maximise the absorption of incident photons. A pathway towards such high efficiencies is the implementation of transparent scattering structures to minimise parasitic losses. We study the performance of these structures by focusing on dielectric/high-band-gap semiconductor scattering layers in an ultra-thin (80 nm) GaAs solar cell. Comparisons with absorptive scattering layers are enabled by presenting data for an equivalent device with metal/dielectric structures. Following a previously reported light management optimisation method which is guided by the dispersion of the avail- able waveguide modes, we find an improved performance for the transparent scattering layers. Our study also compares the light absorption enhancement offered by transparent photonic crystal diffractive arrays to that of transparent quasi-random geometries which target the diffracted power to the most favourable waveguide modes in the device. We find the former designs to have a superior performance in our device of interest, and the latter to suffer from greater reflection losses. Finally, our results also demonstrate the effectiveness of the optimisation method used and its applicability to multiple device architectures for the design of high-efficiency photovoltaics.

The impact of high energy proton radiation, as would be encountered in highly eccentric and Europa orbits, on ultra-thin GaAs solar cells was studied. The cells were irradiated with 68 MeV protons at fluences of 2 × 1012 cm−2 and 1 × 1013cm−2. Cathodoluminescence and dark I-V were used to evaluate the variation of defect density and J 02 with fluence, respectively. The applicability of cathodoluminescence to the study of radiation damage in photovoltaic devices is discussed.

Ever-thinner solar cells are currently of interest to the photovoltaics community and demand the introduction of light-trapping techniques to retain a competitive photovoltaic performance. This work presents a framework for a guided light-trapping design applied to an ultra-thin (< 100 nm) solar cell. The framework is based on a fundamental study of the waveguide modes supported by a realistic device architecture. Mode-coupling is ensured by introducing a scattering layer according to its Fourier spectrum. The framework can be applied to any device architecture and for single or multiple wavelength absorption enhancement, having the flexibility to attain high-efficiency in ever-thinner photovoltaics.

Ultra-thin (less than 100 nm) photovoltaics for space power applications are proposed due to their intrinsic radiation tolerance [1]. They are a potentially enabling technology for space missions in high radiation environments such as Highly Elliptical Earth Orbits (HEO) and the orbits of Jupiter's scientifically interesting moon, Europa. GaAs solar cells with an 80 nm active layer were designed, fabricated and tested under 68 MeV proton irradiation. The results of electrical characterisation before and after proton beam exposure at two different fluences shows their tolerance to these harsh conditions.

Therapeutic hypothermia was a mainstay of severe traumatic brain injury (TBI) management for half a century. Recent trials have suggested that its effect on long-term functional outcome is neutral or negative, despite apparently promising pre-clinical data. Systematic review and meta-analysis is a useful tool to collate experimental data and investigate the basis of its conclusions. We searched three online databases to identify studies testing systemic hypothermia as monotherapy for treatment of animals subjected to a TBI. Data pertaining to TBI paradigm, animal subjects, and hypothermia management were extracted as well as those relating to risk of bias. We pooled outcome data where sufficient numbers allowed and investigated heterogeneity in neurobehavioral outcomes using multi-variate meta-regression. We identified 90 publications reporting 272 experiments testing hypothermia in animals subject to TBI. The subjects were mostly small animals, with well-established models predominating. Target temperature was comparable to clinical trial data but treatment was initiated very early. Study quality was low and there was some evidence of publication bias. Delay to treatment, comorbidity, and blinded outcome assessment appeared to predict neurobehavioral outcome on multi-variate meta-regression. Therapeutic hypothermia appears to be an efficacious treatment in experimental TBI, which differs from the clinical evidence. The pre-clinical literature showed limitations in quality and design and these both appeared to affect neurobehavioral experiment outcome. These should be acknowledged when designing and interpreting pre-clinical TBI studies in the future.

Spinal muscular atrophy (SMA) is a severe childhood neuromuscular disease for which two genetic therapies, Nusinersen (Spinraza, an antisense oligonucleotide), and AVXS-101 (Zolgensma, an adeno-associated viral vector of serotype 9 AAV9), have recently been approved. We investigated the pre-clinical development of SMA genetic therapies in rodent models and whether this can predict clinical efficacy. We have performed a systematic review of relevant publications and extracted median survival and details of experimental design. A random effects meta-analysis was used to estimate and compare efficacy. We stratified by experimental design (type of genetic therapy, mouse model, route and time of administration) and sought any evidence of publication bias. 51 publications were identified containing 155 individual comparisons, comprising 2573 animals in total. Genetic therapies prolonged survival in SMA mouse models by 3.23-fold (95% CI 2.75–3.79) compared to controls. Study design characteristics accounted for significant heterogeneity between studies and greatly affected observed median survival ratios. Some evidence of publication bias was found. These data are consistent with the extended average lifespan of Spinraza- and Zolgensma-treated children in the clinic. Together, these results support that SMA has been particularly amenable to genetic therapy approaches and highlight SMA as a trailblazer for therapeutic development.

To identify Janus kinase (JAK) inhibitors that selectively target gastrointestinal tissues with limited systemic exposures, a class of imidazopyrrolopyridines with a range of physical properties was prepared and evaluated. We identified compounds with low intrinsic permeability and determined a correlation between permeability and physicochemical properties, clogP and tPSA, for a subset of compounds. This low intrinsic permeability translated into compounds displaying high colonic exposure and low systemic exposure after oral dosing at 25 mg/kg in mouse. In a mouse PK/PD model, oral dosing of lead compound 2 demonstrated dose-dependent inhibition of pSTAT phosphorylation in colonic explants post-oral dose but low systemic exposure and no measurable systemic pharmacodynamic activity. We thus demonstrate the utility of JAK inhibitors with low intrinsic permeability as a feasible approach to develop gut-restricted, pharmacologically active molecules with a potential advantage over systemically available compounds that are limited by systemic on-target adverse events.

Aims The impact on extent of resection (EOR) in glioblastoma has been well documented. It is clear that gross-total resection (GTR) confers best overall survival (OS), however the minimum EOR required to confer a survival benefit over biopsy is debated. Recent studies favour partial resection (PR) over biopsy for IDH-wildtype, MGMT-unmethylated tumours. We describe our experiences locally with these principles in mind. Method Retrospective evaluation of a single surgeon cohort. All patients over 18 years old, undergoing a surgical treatment for histologically confirmed GBM in the stated period were included. We collected information on demographics, tumour volume, EOR, complications, adjuvant therapies, molecular profile, and OS. We used log rank tests and Cox Proportional Hazards Models to identify factors associated with OS. Results The patient and tumour characteristics of our cohort were similar to those documented in the literature. The mean age was 56.6 years. 72 patients underwent biopsy and 202 had debulking surgery. Median OS was 11 months. Of those debulked, gross-total resection was achieved in 41 patients (20%); associated median OS was 29 months. Patients receiving partial resection (defined as EOR Conclusion In our experience, partial resection is not a justifiable surgical aim in the typical glioblastoma cohort. The limited benefit that it may confer over biopsy appears to be outweighed by the risk of neurological deficit that affects quality and probably quantity of life. This finding applies to our glioblastoma population in general as well as those specifically with an MGM-unmethylated tumour.

Funder: European Research Council; Id: http://dx.doi.org/10.13039/501100000781, Funder: Engineering and Physical Sciences Research Council; Id: http://dx.doi.org/10.13039/501100000266, Funder: European Union's Horizon 2020, Radiation‐resistant but cost‐efficient, flexible, and ultralight solar sheets with high specific power (W g−1) are the “holy grail” of the new space revolution, powering private space exploration, low‐cost missions, and future habitats on Moon and Mars. Herein, this study investigates an all‐perovskite tandem photovoltaic (PV) technology that uses an ultrathin active layer (1.56 µm) but offers high power conversion efficiency, and discusses its potential for high‐specific‐power applications. This study demonstrates that all‐perovskite tandems possess a high tolerance to the harsh radiation environment in space. The tests under 68 MeV proton irradiation show negligible degradation (22%. Using high spatial resolution photoluminescence (PL) microscopy, it is revealed that defect clusters in GaAs are responsible for the degradation of current space‐PV. By contrast, negligible reduction in PL of the individual perovskite subcells even after the highest dose studied is observed. Studying the intensity‐dependent PL of bare low‐gap and high‐gap perovskite absorbers, it is shown that the VOC, fill factor, and efficiency potentials remain identically high after irradiation. Radiation damage of all‐perovskite tandems thus has a fundamentally different origin to traditional space PV.

Quaternary alloys are essential for the development of high-performance optoelectronic devices. However, immiscibility of the constituent elements can make these materials vulnerable to phase segregation, which degrades the optical and electrical properties of the solid. High-efficiency III-V photovoltaic cells are particularly sensitive to this degradation. InAlAsSb lattice matched to InP is a promising candidate material for high-bandgap subcells of a multijunction photovoltaic device. However, previous studies of this material have identified characteristic signatures of compositional variation, including anomalous low-energy photoluminescence. In this work, atomic-scale clustering is observed in InAlAsSb via quantitative scanning transmission electron microscopy. Image quantification of atomic column intensity ratios enables the comparison with simulated images, confirming the presence of nonrandom compositional variation in this multispecies alloy.

The success of ever-thinner photovoltaics relies on the introduction of light management strategies to enhance the absorption of incident illumination. Tailoring these strategies to maximise the absorption of light requires optimising the complex interplay between multiple design parameters. We study this interplay with a transfer matrix method and rigorous coupled-wave analysis, within the context of waveguide modes in an ultra-thin (80 nm) GaAs solar cell. Based on this study, we develop a framework for light management optimisation which is guided by the underlying optical phenomena that determine the most favourable design parameters. In contrast to other optimisation approaches which exhaustively simulate multiple parameter combinations looking for the highest integrated absorption, our framework reduces the parameter space for optimisation, furthers our fundamental understanding of light management and is applicable to multiple length-scales and device architectures. We demonstrate the power of our framework by using it to compare the light trapping performance of photonic crystal gratings to that of engineered quasi-random structures, finding that photonic crystal gratings offer a superior performance in our device of interest.

Clinical isolates of influenza virus produce pleiomorphic virions, ranging from small spheres to elongated filaments. The filaments are seemingly adaptive in natural infections, but their basic functional properties are poorly understood and functional studies of filaments often report contradictory results. This may be due to artefactual damage from routine laboratory handling, an issue which has been noted several times without being explored in detail. To determine whether standard laboratory techniques could damage filaments, we used immunofluorescence microscopy to rapidly and reproducibly quantify and characterize the dimensions of filaments. Most of the techniques we tested had minimal impact on filaments, but freezing to −70 °C, a standard storage step before carrying out functional studies on influenza viruses, severely reduced their concentration, median length and the infectivity of the whole virion population. We noted that damage from freezing is likely to have affected most of the functional studies of filaments performed to date, and to address this we show that it can be mitigated by snap-freezing or incorporating the cryoprotectant DMSO. We recommend that functional studies of filaments characterize virion populations prior to analysis to ensure reproducibility, and that they use unfrozen samples if possible and cryoprotectants if not. These basic measures will support the robust functional characterizations of filaments that are required to understand their roles in natural influenza virus infections.

Photon gain, which indicates the breakdown of the Principle of Detailed Balance, has been observed in radiatively dominated quantum well solar cells (QWSCs) at illumination levels consistent with around 200x concentration. Evidence comes from three types of experiment. The radiative dark-current extracted from a short-circuit current versus open circuit voltage plot becomes steeper than expected for radiative recombination. The photoluminescence and electro-luminescence spectra from the lowest exciton broaden as illumination increases. We report evidence demonstrating that photon gain results from hot-carrier recombination. Our results support the hypothesis that hot carriers are responsible for the reduced radiative recombination in QWSCs and the voltage enhancement observed in triple-junction QWSCs.

GaAs is an attractive material for space solar cells due to it possessing the highest photovoltaic efficiency among semiconductors. However, material vulnerability to radiation damage is a limiting factor, which should be resolved. This can be done through the optimization of solar cell geometry. Specifically, ultra-thin GaAs solar cells possess increased radiation hardness in combination with high specific power (W/kg) making them desirable for space applications. In this research, modeling of single-junction thin GaAs based solar cells with an active device thickness < 1.6 µm is performed to evaluate cell performance at high irradiation levels (1 MeV electrons with a fluence of 1E15 e-/cm2) associated with high energy orbits. The radiation tolerance of two configurations is evaluated; conventional and rear junction (thick emitter) with a backside gold reflective coating. In addition, solar cell structures utilizing n- and p-type base are simulated. The Hovel model, modified to include the photon recycling effect, is used for modeling. The effect of radiation on GaAs electronic properties is counted through degradation of minority carrier lifetime and changes in the carrier concentration. It’s found that conventional n-emitter/p-base and the rear junction with p-type thick emitter configurations with a heavily doped absorber ~5E18 [cm-3] and thickness below 800 nm have increased radiation hardness with a degradation rate

Harry Smith Vacation Studentship Laboratory-adapted influenza viruses produce predominantly spherical virions. In contrast, clinical and veterinary isolates produce a mixture of virions of different sizes, from 0.1 µm spheres to filaments which can reach tens of microns in length. Filamentous influenza virions were discovered in 1946, but the bulk of influenza research has analysed only spherical forms of the virus and the role of filaments in influenza infections is unclear. Functional studies of filaments require the development of methods to manipulate the ratio of spherical to filamentous virions, and we reasoned that this could be achieved by filtration. To test this, we infected MDCK cells with the filamentous Udorn strain of influenza A virus. We collected virus-containing growth media and passed this through filters with 5 µm, 0.45 µm and 0.2 µm pores. Filtrates and unfiltered virus were compared, using Western blotting to measure their protein composition, plaque assays to measure their infectivity and negative stain transmission electron microscopy to measure individual particle sizes. We found that filtration through a filter with 5 µm pores had little effect on composition, infectivity and the ratio of spherical to filamentous particles. In contrast, sub-micron filters, particularly those with 0.2 µm pores, caused a general depletion of virions but increased the sphere to filament ratio. We therefore concluded that sub-micron pore sizes can be used to preferentially remove filaments from populations of pleomorphic influenza virions, providing a useful tool for subtractive studies of the contribution filaments make to influenza virus infections.

Most laboratory strains of influenza virus produce near-spherical virions, but clinical isolates also produce extended filaments whose biophysical properties are understudied. Most functional studies of filamentous influenza viruses do not include data on the concentration or lengths of the virions, making it hard to interpret their sometimes contradictory results. Furthermore, anecdotal reports suggest that filaments are damaged during routine laboratory handling. Therefore, to understand filament function we require a tool to assess the number and dimensions of filaments in a sample and an assessment of how filaments respond to standard handling procedures. We initially sought to analyse filament populations using negative stain particle counting, but found that this was low-throughput and could not detect particles longer than 10 µm. Instead, we used confocal microscopy with semi-automated image analysis. This allowed a high-throughput, quantitative analysis of length distributions in filament populations. Using this, we assessed the effects of pipetting, vortexing, sonicating, clarification and freezing on filaments. Most procedures did not appreciably alter filament dimensions. Pipetting and vortexing both slightly reduced filament numbers, but their effects were only appreciable after extended treatment. In contrast, freezing substantially reduced the number and median length of filaments, as well as creating ‘kinks’ in filaments which suggest damage to the capsid. We conclude that confocal microscopy can provide the basic measurements needed to interpret functional studies of filamentous strains. Using this approach, we found that freezing filaments causes previously unappreciated damage, which should be considered when planning further research.

The General Circulation Models experience a significant challenge in realistically simulating rainfall over the tropical Maritime Continent (hereafter, MC). Here, we investigate the mechanisms of an improvement in monthly rainfall simulation over the MC region in the UK Met Office Unified Model (version Global Atmosphere 6.0), which occurs when the horizontal resolution is increased from N96 (grid spacing ~135 km) to N216 (~60 km). The increased resolution enhances the area-averaged rainfall rate over the MC, thereby reducing the dry rainfall bias seen in the model at the N96 resolution. We find that the enhanced area-averaged rainfall is mostly due to an increase in the medium rainfall rates that occurs over the MC islands in the N216 experiment. The rainfall change is predominantly associated with changes in the atmospheric convective circulation and the related horizontal moisture flux convergence. The vertical profiles of convective circulation show a strong sensitivity to the increased horizontal resolution over the MC islands, but not over the surrounding oceans. It is shown that a significant underestimation of the deep convection (as opposed to the shallow convection) in the N96 experiment is primarily responsible for the stronger dry bias in this experiment. We present evidence that the dry bias, and the associated weaker deep convection, are in part caused by the strongly smoothed orography used in the N96 experiment, which provides a weaker orographic lifting of the moist surface air (in a conditionally unstable atmosphere) than that in the N216 experiment.

The CSIRO Mk3L climate system model is a coupled general circulation model, designed primarily for millennial-scale climate simulations and palaeoclimate research. Mk3L includes components which describe the atmosphere, ocean, sea ice and land surface, and combines computational efficiency with a stable and realistic control climatology. This paper describes the model physics and software, analyses the control climatology, and evaluates the ability of the model to simulate the modern climate. Mk3L incorporates a spectral atmospheric general circulation model, a z-coordinate ocean general circulation model, a dynamic-thermodynamic sea ice model and a land surface scheme with static vegetation. The source code is highly portable, and has no dependence upon proprietary software. The model distribution is freely available to the research community. A 1000-yr climate simulation can be completed in around one-and-a-half months on a typical desktop computer, with greater throughput being possible on high-performance computing facilities. Mk3L produces realistic simulations of the larger-scale features of the modern climate, although with some biases on the regional scale. The model also produces reasonable representations of the leading modes of internal climate variability in both the tropics and extratropics. The control state of the model exhibits a high degree of stability, with only a weak cooling trend on millennial timescales. Ongoing development work aims to improve the model climatology and transform Mk3L into a comprehensive earth system model.

Adenovirus has enormous potential as a gene-therapy vector, but preexisting immunity limits its widespread application. What is responsible for this immune block is unclear because antibodies potently inhibit transgene expression without impeding gene transfer into target cells. Here we show that antibody prevention of adenoviral gene delivery in vivo is mediated by the cytosolic antibody receptor TRIM21. Genetic KO of TRIM21 or a single-antibody point mutation is sufficient to restore transgene expression to near-naïve immune levels. TRIM21 is also responsible for blocking cytotoxic T cell induction by vaccine vectors, preventing a protective response against subsequent influenza infection and an engrafted tumor. Furthermore, adenoviral preexisting immunity can lead to an augmented immune response upon i.v. administration of the vector. Transcriptomic analysis of vector-transduced tissue reveals that TRIM21 is responsible for the specific up-regulation of hundreds of immune genes, the majority of which are components of the intrinsic or innate response. Together, these data define a major mechanism underlying the preimmune block to adenovirus gene therapy and demonstrate that TRIM21 efficiently blocks gene delivery in vivo while simultaneously inducing a rapid program of immune transcription.

We recently demonstrated an ultra-thin solar cell with increased radiation tolerance as compared to a traditionally thick absorber counterpart. However, as the active region of the device was reduced so was the absorption with respect to state of the art devices. Therefore, we have implemented nanosphere natural photolithography to fabricate ordered and random arrays of micropillar structures leading to enhanced light absorption within an ultra-thin solar cell. We will discuss the fabrication process and illustrate the effectiveness of integrating light trapping structures within an ultra-thin solar cell design.

Hot carrier solar cells (HCSCs) have been proposed as potential systems to increase the conversion efficiency of single gap solar cells beyond the Shockley-Queisser limit. Despite a great deal of recent progress in HCSCs, designing an effective and efficient hot carrier absorber remains challenging. To evaluate the efficiency of any proposed absorber accurate determination of the carrier temperature is required. This can be non-trivial, particularly in the quantum wells (QW) where state-filling effects can complicate the simple extraction of carrier temperature from photoluminescence (PL) spectra. Specifically, the PL may be distorted if there are other linewidth broadening mechanisms prevalent in addition to non-equilibrium carriers. These may include; in addition to state filling, the effects of phonons and system inhomogeneities, all of which serve to perturb the PL linewidth. In this study, an InGaAsP QW with a type-II band alignment is investigated using continuous wave power and temperature dependent PL to evaluate the effects of broadening on the extraction of the true carrier temperature in the system [1]. Since there is a relatively small energy separation between the ground and first excited state transitions in the QW studied, state filling effects can be controlled and their contribution to the linewidth evaluated, using various conditions and combinations of excitation power and lattice temperature. The role of phonons is also presented, and supported within the framework of a theoretical model that includes the various phononic processes and their temperature dependent contribution to the PL. This work is supported by the National Science Foundation Grant ECCS #1610062 [1] Esmaielpour, Hamidreza, Vincent R. Whiteside, Louise C. Hirst, Joseph G. Tischler, Chase T. Ellis, Matthew P. Lumb, David V. Forbes, Robert J. Walters, and Ian R. Sellers. Progress in Photovoltaics: Research and Applications (2017).

Ultrathin III–V solar cells are sought after for their relatively low cost and potential novel applications such as hot-carrier solar cells, but currently suffer from low power-conversion efficiency. Now, light-trapping nanostructures have been demonstrated to enable efficiency of 19.9% in a 205-nm-thick GaAs solar cell.